JP7528185B2 - Liquid crystal display device - Google Patents

Description

The present invention relates to an article, a method, or a method for producing an article, and in particular to a display device or semiconductor device, in particular to a display device, and in particular to an active matrix liquid crystal display device.

In recent years, the development of liquid crystal display devices and EL display devices as display devices has progressed rapidly. In particular, the spread of liquid crystal display devices has been remarkable. Liquid crystal display devices are required to have high brightness, high contrast, high-speed response, wide viewing angle, etc. In addition, reduction of power consumption, weight reduction, and size reduction are also important issues for liquid crystal display devices mounted on portable electronic devices.

Various technologies have been developed to widen the viewing angle of liquid crystal display devices. For example, MVA (Multi Vertical Domain) is a technology for widening the viewing angle.
PVA (Patterned Vertical Alignment) method
t. Hereafter referred to as PVA.) method and CPA (Continuous Pinwheel
Although this technology has expanded the viewing angle compared to the past, it is still insufficient. Therefore, a technology has been developed to improve the viewing angle characteristics by dividing one pixel into two sub-pixels to make the alignment state of the liquid crystal different, and creating the illusion that the tilt angle of the liquid crystal molecules is averaged and a uniform display is obtained from any direction (for example, Patent Document 1).

JP 2006-276582 A

In liquid crystal display devices, the viewing angle characteristics can be improved by providing sub-pixels in a pixel and allowing the pixel to have multiple alignment states. However, the viewing angle characteristics are still not sufficient, and there is a possibility that the viewing angle characteristics can be improved by adding further sub-pixels.

However, simply increasing the number of subpixels leads to problems such as a decrease in aperture ratio and an increase in the number of driving circuits, which not only increases manufacturing costs but also reduces the performance of the display device itself. Specifically, a decrease in aperture ratio leads to a decrease in brightness and contrast, and an increase in power consumption. Alternatively, the layout density of pixels increases, which reduces manufacturing yield and increases costs. Alternatively, an increase in the number of subpixels increases the number of image signals to be input. This increases the number of connection points between the glass substrate and the external driving circuits. As a result, reliability decreases due to poor contact, etc.

An object of the present invention is to provide a display device having excellent viewing angle characteristics while maintaining performance as a display device. Alternatively, an object of the present invention is to provide a display device having high reliability. Alternatively, an object of the present invention is to provide a display device having high contrast. Alternatively, an object of the present invention is to provide a lightweight display device. Alternatively, an object of the present invention is to provide a display device having a small size. Alternatively, an object of the present invention is to provide a display device having high brightness. Alternatively, an object of the present invention is to provide a display device having low power consumption. Alternatively, an object of the present invention is to provide a display device having a high aperture ratio. Alternatively, an object of the present invention is to provide a display device having low manufacturing costs.

One aspect of the present invention is a liquid crystal display device having three or more liquid crystal elements per pixel, with a different voltage value applied to each of the liquid crystal elements. Different voltages are applied to each liquid crystal element by arranging an element that divides the applied voltage. Alternatively, an element that converts a current to a voltage, or an element that converts a voltage to a current, is arranged. Examples of such an element include a capacitance element, a resistance element, a nonlinear element, a switch, a transistor, a diode-connected transistor, a diode (PIN type, PN type, Schottky type, MIM type, MIS type, etc.), and an inductor element.

The switch may be of various types. Examples include electrical switches and mechanical switches. In other words, any switch that can control the flow of current may be used.
For example, the switch may be a transistor (e.g., a bipolar transistor, a MOS transistor, etc.), a diode (e.g., a PN diode, a PI
N-Diode, Schottky Diode, MIM (Metal Insulator M
etal) diode, MIS (Metal Insulator Semiconductor
A diode, a diode-connected transistor, a thyristor, etc. can be used as the switch. Alternatively, a logic circuit combining these can be used as the switch.

An example of a mechanical switch is a switch using MEMS (microelectromechanical system) technology, such as a digital micromirror device (DMD). The switch has an electrode that can be mechanically moved, and operates by controlling connection and disconnection by the movement of the electrode.

When a transistor is used as a switch, the transistor operates simply as a switch, so the polarity (conductivity type) of the transistor is not particularly limited. However, when it is desired to suppress the off-current, it is desirable to use a transistor with a polarity with a smaller off-current. Examples of transistors with a smaller off-current include transistors having an LDD region and transistors having a multi-gate structure. Alternatively, when the potential of the source terminal of a transistor operated as a switch operates in a state close to the potential of a low-potential power supply (Vss, GND, 0V, etc.), it is desirable to use an N-channel transistor. On the other hand, when the potential of the source terminal operates in a state close to the potential of a high-potential power supply (Vdd, etc.), it is desirable to use a P-channel transistor. This is because, when an N-channel transistor operates in a state close to the potential of a low-potential power supply, and when a P-channel transistor operates in a state close to the potential of a high-potential power supply, the absolute value of the voltage between the gate and the source can be increased, so that it is easy to operate as a switch. This is because the magnitude of the output voltage is less likely to be reduced because the source follower operation is less likely to occur.

In addition, both N-channel and P-channel transistors are used to form a CMOS
An S-type switch may be used as the switch. If a CMOS type switch is used, a current flows if either a P-channel transistor or an N-channel transistor is conductive, so that the switch can function easily as a switch. For example, whether the voltage of the input signal to the switch is high or low, the switch can output an appropriate voltage. Furthermore, the voltage amplitude value of the signal for turning the switch on or off can be reduced, so that power consumption can be reduced.

In addition, when a transistor is used as a switch, the switch has an input terminal (one of the source terminal and the drain terminal), an output terminal (the other of the source terminal and the drain terminal),
A switch has a terminal (gate terminal) for controlling conduction. On the other hand, when a diode is used as a switch, the switch may not have a terminal for controlling conduction. Therefore, using a diode as a switch rather than a transistor can reduce the amount of wiring for controlling the terminal.

In addition, when it is explicitly stated that A and B are connected, this includes the cases where A and B are electrically connected, where A and B are functionally connected, and where A and B are directly connected. Here, A and B are objects (e.g., devices, elements, circuits, wiring, electrodes, terminals, conductive films, layers, etc.). Therefore, it is not limited to a specific connection relationship, for example, a connection relationship shown in a figure or text, but also includes connection relationships other than those shown in a figure or text.

For example, in the case where A and B are electrically connected, one or more elements (e.g., switches, transistors, capacitive elements, inductors, resistive elements, diodes, etc.) that enable the electrical connection between A and B may be arranged between A and B. Alternatively, in the case where A and B are functionally connected, one or more circuits (e.g., logic circuits (inverters, NAND circuits, NOR circuits, etc.), signal conversion circuits (DA conversion circuits, AD conversion circuits, gamma correction circuits, etc.), potential level conversion circuits (power supply circuits (boosting circuits, step-down circuits, etc.), level shifter circuits that change the potential level of a signal, etc.), voltage sources, current sources, switching circuits, amplifier circuits (circuits that can increase the signal amplitude or current amount, operational amplifiers, differential amplifier circuits, source follower circuits, buffer circuits, etc.), signal generation circuits, memory circuits, control circuits, etc.) that enable the functional connection between A and B may be arranged between A and B. Alternatively, in the case where A and B are directly connected, A and B may be directly connected without any other elements or circuits between A and B.

In addition, when it is explicitly stated that A and B are directly connected, this includes the case where A and B are directly connected (i.e., the case where A and B are connected without any other element or circuit between them) and the case where A and B are electrically connected (i.e., the case where A and B are connected with another element or circuit between them).

In addition, when it is explicitly stated that A and B are electrically connected, it means the following cases: when A and B are electrically connected (i.e., when A and B are connected with another element or circuit between them), when A and B are functionally connected (i.e., when A and B are functionally connected with another circuit between them), and when A and B are directly connected (
In other words, the term "electrically connected" includes the case where A and B are connected without any other element or circuit between them. In other words, when it is explicitly stated that A and B are electrically connected, it is the same as when it is explicitly stated that A and B are connected.

Display device Note that the display element, the display device which is a device having the display element, the light emitting element, and the light emitting device which is a device having the light emitting element can be in various forms and can have various elements. For example, the display element, the display device, the light emitting element, or the light emitting device can be an EL element (EL element including organic and inorganic materials, organic EL element, inorganic EL element), an electron emission element, a liquid crystal element,
Display media whose contrast, brightness, reflectance, transmittance, etc. change due to electro-magnetic effects can be used, such as electronic ink, electrophoretic elements, grating light valves (GLV), plasma displays (PDP), digital micromirror devices (DMD), piezoelectric ceramic displays, carbon nanotubes, etc. In addition, display devices using EL elements include EL displays, and display devices using electron emission elements include field emission displays (FEDs) and SED type flat panel displays (SEDs).
Examples of display devices using liquid crystal elements include liquid crystal displays (transmissive liquid crystal displays, semi-transmissive liquid crystal displays, reflective liquid crystal displays, direct-view liquid crystal displays, and projection liquid crystal displays), and examples of display devices using electronic ink or electrophoretic elements include electronic paper.

The EL element is an element having an anode, a cathode, and an EL layer sandwiched between the anode and the cathode. The EL layer may be one that utilizes light emission (fluorescence) from singlet excitons,
Examples of materials that can be used include those that utilize light emission from triplet excitons (phosphorescence), those that utilize light emission from singlet excitons (fluorescence) and those that utilize light emission from triplet excitons (phosphorescence), those formed from organic substances, those formed from inorganic substances, those that include those formed from organic substances and those formed from inorganic substances, polymeric materials, low molecular weight materials, and those that include polymeric materials and low molecular weight materials. However, the present invention is not limited to these, and E
A variety of elements can be used as the L element.

The electron-emitting device is an element that extracts electrons by concentrating a high electric field on a sharp cathode.
For example, the electron-emitting element may be a Spindt type, a carbon nanotube (CNT) type, a metal-
MIM (Metal-Insulator-Metal) type, which stacks insulator-metal, and MIS (Metal-Insulator-Semiconductor) type, which stacks metal-insulator-semiconductor.
inductor type, MOS type, silicon type, thin film diode type, diamond type, surface conduction emitter SCD type, anode type, diamond type, surface conduction emitter SCD type, metal
It is possible to use thin film types such as an insulator-semiconductor-metal type, HEED type, EL type, porous silicon type, surface conduction (SED) type, etc. However, it is not limited to these, and various types can be used as the electron emission element.

A liquid crystal element is an element that controls the transmission or non-transmission of light by the optical modulation action of liquid crystal, and is composed of a pair of electrodes and liquid crystal.
It is controlled by an electric field (including a horizontal electric field, a vertical electric field, or an oblique electric field) applied to the liquid crystal. The liquid crystal element may be a nematic liquid crystal, a cholesteric liquid crystal, a smectic liquid crystal, a discotic liquid crystal, a thermotropic liquid crystal, a lyotropic liquid crystal, a low molecular weight liquid crystal, a polymer liquid crystal, a ferroelectric liquid crystal, an antiferroelectric liquid crystal, a main chain type liquid crystal, a side chain type polymer liquid crystal, a plasma addressed liquid crystal (PDLC), a banana type liquid crystal, a twisted nematic (TN) type liquid crystal, or a combination thereof.
Nematic mode, STN (Super Twisted Nematic) mode, IPS (In-Plane-Switching) mode, FFS (Fringe
Field Switching mode, MVA (Multi-domain Ve)
Vertical Alignment mode, PVA (Patterned Verti
cal Alignment), ASV (Advanced Super View) mode, ASM (Axially Symmetric aligned Micro-c)
ell) mode, OCB (Optical Compensated Birefringent
ence) mode, ECB (Electrically Controlled Bi
reference mode, FLC (Ferroelectric Liquid)
Crystal) mode, AFLC (AntiFerroelectric Liquor)
id Crystal) mode, PDLC (Polymer Dispersed Li
A liquid crystal display (Quid Crystal) mode, a guest-host mode, etc., can be used. However, the present invention is not limited to these, and various types of liquid crystal elements can be used.

The electronic paper may be displayed by molecules such as optical anisotropy and dye molecule orientation, particles such as electrophoresis, particle movement, particle rotation, and phase change, one end of the film may be moved, molecular coloring/phase change, molecular light absorption, or electrons and holes may be combined to emit light. For example, the electronic paper may be a microcapsule type electrophoresis, a horizontal movement type electrophoresis, a vertical movement type electrophoresis, a spherical twist ball, a magnetic twist ball, a cylindrical twist ball system, a charged toner, an electronic liquid powder, a magnetic electrophoresis type, a magnetic heat sensitive system, an electrowetting, a light scattering (transparent and opaque), a cholesteric liquid crystal/photoconductive layer, a cholesteric liquid crystal, a bistable nematic liquid crystal, a ferroelectric liquid crystal, a dichroic dye/liquid crystal dispersion type, a movable film, a leuco dye coloring/discoloration, a photochromic, an electrochromic, an electrodeposition, or a flexible organic EL. However, the electronic paper is not limited to these, and various types may be used as the electronic paper. Here, by using microcapsule-type electrophoresis, it is possible to solve the problems of the electrophoretic method, such as aggregation and precipitation of electrophoretic particles. Electronic liquid powders have the advantages of high-speed response, high reflectance, wide viewing angle, low power consumption, and memory properties.

A plasma display has a structure in which a substrate with electrodes formed on its surface and a substrate with electrodes and minute grooves formed on its surface and a phosphor layer formed in the grooves are placed facing each other at a narrow gap, and rare gas is sealed inside. By applying a voltage between the electrodes, ultraviolet light is generated, causing the phosphor to glow, and display can be performed.
The plasma display panel may be an A-type PDP or an AC-type PDP.
SW (Address While Sustain) drive, ADS (Address Display Set) that divides a subframe into a reset period, an address period, and a sustain period
Parated) drive, CLEAR (Low Energy Address and
Reduction of False Contour Sequence) drive, A
LIS (Alternate Lighting of Surfaces) method, TE
RES (Technology of Reciprocal Susfainer) driving, etc. can be used. However, the present invention is not limited to this, and various types of plasma displays can be used.

In addition, as light sources for display devices that require a light source, such as liquid crystal displays (transmissive liquid crystal displays, semi-transmissive liquid crystal displays, reflective liquid crystal displays, direct-view liquid crystal displays, projection liquid crystal displays), display devices using grating light valves (GLVs), display devices using digital micromirror devices (DMDs), etc., electroluminescence, cold cathode tubes, hot cathode tubes, LEDs, laser light sources, mercury lamps, etc. can be used. However, the light source is not limited to these, and various other light sources can be used.

Transistor Types Various types of transistors can be used as the transistor. Therefore, there is no limitation on the type of transistor to be used. For example, a transistor made of amorphous silicon, a transistor made of polycrystalline silicon,
Thin film transistors (TFTs) having a non-single crystal semiconductor film, such as microcrystalline (also called semi-amorphous) silicon, can be used. There are various advantages to using TFTs. For example, since they can be manufactured at a lower temperature than single crystal silicon, it is possible to reduce manufacturing costs or increase the size of the manufacturing equipment. Since the manufacturing equipment can be made larger, they can be manufactured on a large substrate. Therefore, since a large number of display devices can be manufactured at the same time, they can be manufactured at low cost. Furthermore, since the manufacturing temperature is low, a substrate with poor heat resistance can be used. Therefore, transistors can be manufactured on a transparent substrate. And,
The light transmission in the display element can be controlled by using a transistor on a transparent substrate. Alternatively, since the film thickness of the transistor is thin, a part of the film constituting the transistor can transmit light. Therefore, the aperture ratio can be improved.

In addition, by using a catalyst (nickel, etc.) when manufacturing polycrystalline silicon, it is possible to further improve the crystallinity and manufacture transistors with good electrical characteristics. As a result, it is possible to manufacture transistors with good electrical characteristics such as gate driver circuits (scanning line driver circuits) and source driver circuits (signal line driver circuits).
Signal processing circuits (signal generation circuits, gamma correction circuits, DA conversion circuits, etc.) can be integrally formed on the substrate.

In addition, when manufacturing microcrystalline silicon, by using a catalyst (nickel, etc.), it is possible to further improve the crystallinity and manufacture a transistor with good electrical characteristics. In this case, the crystallinity can be improved by simply applying heat treatment without performing laser irradiation. As a result, a gate driver circuit (scanning line driving circuit) and a part of a source driver circuit (analog switch, etc.) can be integrally formed on a substrate. Furthermore, when laser irradiation is not performed for crystallization, unevenness in the crystallinity of silicon can be suppressed. Therefore, a beautiful image can be displayed.

However, it is possible to produce polycrystalline silicon or microcrystalline silicon without using a catalyst (such as nickel).

It is desirable to improve the crystallinity of silicon to polycrystalline or microcrystalline, etc., over the entire panel, but this is not a limitation. The crystallinity of silicon may be improved only in a partial region of the panel. Selective improvement of crystallinity is possible by selectively irradiating a laser beam, etc. For example, the laser beam may be irradiated only to a peripheral circuit region other than the pixels. Alternatively, the laser beam may be irradiated only to regions such as the gate driver circuit and the source driver circuit. Alternatively, the laser beam may be irradiated only to a portion of the source driver circuit (
For example, the laser light may be irradiated only to the region of the semiconductor device (analog switch). As a result, the crystallization of silicon can be improved only in the region where the circuit needs to operate at high speed. Since the pixel region does not need to operate at high speed, the pixel circuit can operate without any problem even if the crystallinity is not improved. Since the region where the crystallinity needs to be improved is small,
The manufacturing process can be shortened, throughput can be improved, and manufacturing costs can be reduced. A smaller number of manufacturing devices are also required, which can reduce manufacturing costs.

Alternatively, transistors can be formed using a semiconductor substrate, an SOI substrate, or the like. This makes it possible to manufacture transistors that have little variation in characteristics, size, shape, and the like, have a high current supply capability, and are small in size. By using these transistors, it is possible to reduce the power consumption of a circuit or to increase the integration density of the circuit.

Or, ZnO, a-InGaZnO, SiGe, GaAs, IZO, ITO, SnO
It is possible to use transistors having compound semiconductors or oxide semiconductors such as those mentioned above, and further, thin film transistors in which these compound semiconductors or oxide semiconductors are thin-filmed. This allows the manufacturing temperature to be lowered, and it is possible to manufacture transistors at room temperature, for example. As a result, it is possible to form transistors directly on substrates with low heat resistance, such as plastic substrates and film substrates. It is to be noted that these compound semiconductors or oxide semiconductors can be used not only in the channel portion of a transistor, but also for other purposes.
For example, these compound semiconductors or oxide semiconductors can be used as resistor elements, pixel electrodes, transparent electrodes, etc. Furthermore, they can be formed or deposited simultaneously with transistors, thereby reducing costs.

Alternatively, a transistor formed by inkjet or printing can be used. This allows manufacturing at room temperature, low vacuum, or on a large substrate. Since manufacturing can be performed without using a mask (reticle), the layout of the transistor can be easily changed. Furthermore, since there is no need to use a resist,
This reduces material costs and the number of processes. Furthermore, because the film is applied only to the necessary parts, there is less waste of material and costs are lower than with a method that involves forming a film over the entire surface and then etching it.

Alternatively, a transistor having an organic semiconductor or a carbon nanotube can be used. This allows the transistor to be formed on a substrate that can be bent, and therefore the transistor can be made resistant to impact.

Furthermore, transistors of various structures can be used. For example, MOS transistors, junction transistors, bipolar transistors, etc. can be used as transistors. By using MOS transistors, the size of the transistors can be reduced. Therefore, a large number of transistors can be mounted. By using bipolar transistors, a large current can be passed. Therefore, the circuit can be operated at high speed.

It is also possible to form a mixture of MOS transistors, bipolar transistors, etc. on one substrate, thereby achieving low power consumption, miniaturization, high speed operation, etc.

Various other transistors can also be used.

The transistors can be formed using various substrates. The type of substrate is not limited to a specific one. Examples of the substrate include a single crystal substrate, an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a paper substrate, a cellophane substrate, a stone substrate, a wood substrate, a cloth substrate (including natural fibers (silk, cotton, hemp), synthetic fibers (nylon, polyurethane, polyester), or regenerated fibers (acetate, cupra, rayon, regenerated polyester), etc.), a leather substrate, a rubber substrate, a stainless steel substrate, a substrate having stainless steel foil, etc. Alternatively, the skin (skin surface, dermis) or subcutaneous tissue of an animal such as a human may be used as the substrate. Alternatively, a transistor may be formed using a certain substrate, and then the transistor may be transferred to another substrate, and the transistor may be disposed on the other substrate. The substrate on which the transistor is transferred may be a single crystal substrate, an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a paper substrate, a cellophane substrate, a stone substrate, a wood substrate, a cloth substrate (including natural fibers (silk, cotton, hemp), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate, cupra, rayon, regenerated polyester) or the like), a leather substrate, a rubber substrate, a stainless steel substrate, a substrate having stainless steel foil, or the like. Alternatively, the skin (skin surface, dermis) or subcutaneous tissue of an animal such as a human may be used as the substrate. Alternatively, a transistor may be formed using a certain substrate, and the substrate may be polished to make it thinner. The substrate to be polished may be a single crystal substrate, an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a paper substrate, a cellophane substrate, a stone substrate, a wood substrate, a cloth substrate (including natural fibers (silk, cotton, hemp), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate, cupra, rayon, regenerated polyester) or the like), a leather substrate, a rubber substrate,
A stainless steel substrate, a substrate having stainless steel foil, or the like can be used. Alternatively, the skin (superficial layer, dermis) or subcutaneous tissue of an animal such as a human may be used as the substrate. By using such a substrate, it is possible to form transistors with good characteristics, form transistors with low power consumption, manufacture devices that are not easily broken, provide heat resistance, and reduce the weight or thickness of the device.

The transistor configuration can take various forms. It is not limited to a specific configuration. For example, a multi-gate structure with two or more gate electrodes may be used. With the multi-gate structure, the channel regions are connected in series, resulting in a configuration in which multiple transistors are connected in series. The multi-gate structure can reduce the off-current and improve the transistor's withstand voltage, thereby improving reliability. Alternatively, with the multi-gate structure, even if the drain-source voltage changes when operating in the saturation region, the drain-source current does not change much, and the slope of the voltage-current characteristic can be made flat. By utilizing the characteristic that the slope of the voltage-current characteristic is flat, an ideal current source circuit or an active load with a very high resistance value can be realized. As a result, a differential circuit or a current mirror circuit with good characteristics can be realized. As another example, a structure in which gate electrodes are arranged above and below the channel may be used. By using a structure in which gate electrodes are arranged above and below the channel, the channel region increases, so that the current value can be increased, or the S value can be reduced by making it easier for a depletion layer to be formed. When gate electrodes are arranged above and below the channel, a configuration in which multiple transistors are connected in parallel is achieved.

Alternatively, the gate electrode may be disposed above the channel region, or the gate electrode may be disposed below the channel region. Alternatively, the gate electrode may be disposed in a positive staggered structure or an inverted staggered structure, the channel region may be divided into a plurality of regions, the channel region may be connected in parallel, or the channel region may be connected in series. Alternatively, the source electrode or the drain electrode may overlap the channel region (or a part thereof). By forming a structure in which the source electrode or the drain electrode overlaps the channel region (or a part thereof), it is possible to prevent charges from accumulating in a part of the channel region, which may cause the operation to become unstable. Alternatively, an LDD region may be provided. By providing the LDD region, it is possible to reduce the off-current or improve the reliability by improving the breakdown voltage of the transistor. Alternatively, by providing the LDD region, even if the drain-source voltage changes when operating in the saturation region, the drain-source current does not change much, and the slope of the voltage-current characteristic can be made flat.

In addition, various types of transistors can be used, and various substrates can be used to form the transistors. Therefore, all of the circuits required to realize the predetermined function may be formed on the same substrate. For example, all of the circuits required to realize the predetermined function may be formed using a glass substrate, a plastic substrate, a single crystal substrate, or an SOI substrate, or may be formed using various substrates. By forming all of the circuits required to realize the predetermined function using the same substrate, it is possible to reduce the cost by reducing the number of components, or to improve the reliability by reducing the number of connections with the circuit components. Alternatively, a part of the circuit required to realize the predetermined function may be formed on a certain substrate, and another part of the circuit required to realize the predetermined function may be formed on another substrate. In other words, all of the circuits required to realize the predetermined function may not be formed using the same substrate. For example, a part of the circuit required to realize a predetermined function may be formed on a glass substrate using transistors, and another part of the circuit required to realize a predetermined function may be formed on a single crystal substrate, and an IC chip composed of transistors formed using the single crystal substrate may be connected to the glass substrate by COG (Chip On Glass), and the IC chip may be disposed on the glass substrate. Alternatively, the IC chip may be connected to the glass substrate by TAB (Tape Automated Bonding) or a printed circuit board. In this way, by forming a part of the circuit on the same substrate, it is possible to reduce the cost by reducing the number of components, or to improve reliability by reducing the number of connections with the circuit components. Alternatively, since the circuits of the parts with high driving voltage and high driving frequency consume large power consumption, the circuits of such parts are not formed on the same substrate, but instead, for example, the circuits of those parts are formed on a single crystal substrate, and an IC chip composed of those circuits is used, thereby preventing an increase in power consumption.

In addition, one pixel indicates one element whose brightness can be controlled. Therefore, as an example, one pixel indicates one color element, and the brightness is expressed by one color element. In this case, in the case of a color display device consisting of color elements of R (red), G (green), and B (blue), the minimum unit of an image is composed of three pixels, an R pixel, a G pixel, and a B pixel. In addition, the color elements are not limited to three colors, and three or more colors may be used, or colors other than RGB may be used. For example, white may be added to make it RGBW (W is white). Alternatively, one or more colors such as yellow, cyan, magenta, emerald green, and vermilion may be added to RGB. Alternatively, for example, a color similar to at least one of the colors in RGB may be added to RGB. For example, it may be R, G, B1, and B2. B1 and B2 are both blue, but have slightly different frequencies. Similarly, it may be R1, R2, G, and B. By using such color elements, it is possible to display an image closer to the real thing. By using such color elements, it is possible to reduce power consumption. As another example, when brightness is controlled using multiple regions for one color element, one of the regions may be regarded as one pixel. Therefore, as an example, when area gradation is performed or when sub-pixels (
When the pixel has a subpixel, there are multiple regions for controlling brightness for one color element,
The gradation is expressed by the whole, but one area for controlling brightness may be regarded as one pixel. In that case, one color element is composed of multiple pixels. Or, even if there are multiple areas for controlling brightness in one color element, they can be collectively expressed as
One color element may be one pixel. In that case, one color element is composed of one pixel. Alternatively, when brightness is controlled using multiple regions for one color element, the size of the region that contributes to the display may differ depending on the pixel. Alternatively, the viewing angle may be widened by slightly differentiating the signals supplied to the multiple regions for controlling brightness per color element.
The potentials of the pixel electrodes of the multiple regions for each of the four color elements may be different from each other, so that the voltages applied to the liquid crystal molecules differ from pixel electrode to pixel electrode, thereby making it possible to widen the viewing angle.

In addition, when it is explicitly stated that one pixel (three colors) is used, it means that one pixel is considered to consist of three pixels of R, G, and B. When it is explicitly stated that one pixel (one color), it means that when there are multiple regions for one color element, all of them are considered to be one pixel.

In addition, the pixels may be arranged (distributed) in a matrix. Here, the arrangement (arrangement) of the pixels in a matrix includes the case where the pixels are arranged in a straight line in the vertical or horizontal direction, or the case where they are arranged in a jagged line. Therefore, for example, when performing full-color display with three color elements (for example, RGB), it includes the case where the pixels are arranged in stripes, or the case where the dots of the three color elements are arranged in delta. Furthermore, it also includes the case where the pixels are arranged in a Bayer arrangement. In addition, the color elements are not limited to three colors, and may be more than three colors, for example, RGBW (W is white), or RGB with one or more colors such as yellow, cyan, magenta, etc. added. In addition, the size of the display area may be different for each dot of the color elements. This can reduce power consumption or extend the life of the display element.

Note that an active matrix system in which pixels have active elements, or a passive matrix system in which pixels do not have active elements can be used.

In the active matrix method, not only transistors but also various other active elements (non-linear elements) can be used as active elements. For example, MIM (Metal Insulator Metal) and TFD
It is also possible to use thin film diodes (Thin Film Diodes). These elements require fewer manufacturing steps, which allows for reduced manufacturing costs and improved yields. Furthermore, the size of the elements is small, which allows for improved aperture ratios, lower power consumption, and higher brightness.

As an alternative to the active matrix type, a passive matrix type that does not use active elements (active elements, nonlinear elements) can also be used. Since no active elements (active elements, nonlinear elements) are used, the number of manufacturing steps is reduced, and it is possible to reduce manufacturing costs and improve yields. Since no active elements (active elements, nonlinear elements) are used, it is possible to improve the aperture ratio, thereby achieving low power consumption and high brightness.

A transistor is an element having at least three terminals including a gate, a drain, and a source, and has a channel region between the drain region and the source region, and can pass a current through the drain region, the channel region, and the source region. Here, the source and the drain vary depending on the structure and operating conditions of the transistor, so it is difficult to determine which is the source or the drain. Therefore, in this document (specification, claims, drawings, etc.), the regions that function as the source and the drain may not be called the source or the drain. In that case, as an example, they may be referred to as the first terminal and the second terminal, respectively. Alternatively, they may be referred to as the first electrode and the second electrode, respectively. Alternatively, they may be referred to as the source region and the drain region.

The transistor may be an element having at least three terminals including a base, an emitter, and a collector. In this case, the emitter and the collector may be similarly referred to as a first terminal and a second terminal.

The term "gate" refers to the whole including the gate electrode and the gate wiring (also called a gate line, gate signal line, scanning line, scanning signal line, etc.), or a part of them. The term "gate electrode" refers to a conductive film that overlaps the semiconductor forming the channel region with a gate insulating film interposed therebetween. A part of the gate electrode is called an LDD (Lightly Doped) film.
In some cases, the gate wiring may overlap with a gate-insulating film between the gate electrodes of the transistors, between the gate electrodes of the pixels, or between another wiring.

However, there are some areas (regions,
Such a portion (region, conductive film, wiring, etc.) may be called a gate electrode or a gate wiring. In other words, the gate electrode and the gate wiring are
There are also regions that cannot be clearly distinguished. For example, when a part of the extended gate wiring overlaps with the channel region, that part (region, conductive film, wiring, etc.) functions as a gate wiring, but also functions as a gate electrode. Therefore, such a part (region, conductive film, wiring, etc.) may be called either a gate electrode or a gate wiring.

In addition, a part (region, conductive film, wiring, etc.) formed of the same material as the gate electrode and connected to form the same island as the gate electrode may also be called a gate electrode. Similarly, a part (region, conductive film, wiring, etc.) formed of the same material as the gate wiring and connected to form the same island as the gate wiring may also be called a gate wiring. In the strict sense, such a part (region, conductive film, wiring, etc.) may not overlap with the channel region or may not have the function of connecting to another gate electrode. However, due to the relationship of the specifications at the time of manufacture, there is a part (region, conductive film, wiring, etc.) formed of the same material as the gate electrode or gate wiring and connected to form the same island as the gate electrode or gate wiring. Therefore, such a part (region, conductive film, wiring, etc.) may also be called a gate electrode or gate wiring.

For example, in a multi-gate transistor, one gate electrode and another gate electrode are often connected by a conductive film made of the same material as the gate electrodes. Such a portion (region, conductive film, wiring, etc.) may be called a gate wiring because it is a portion (region, conductive film, wiring, etc.) for connecting the gate electrodes, but since a multi-gate transistor can also be regarded as one transistor, it may also be called a gate electrode. In other words, a portion (region, conductive film, wiring, etc.) that is made of the same material as the gate electrode or gate wiring and is connected to form the same island as the gate electrode or gate wiring is called a gate wiring.
Furthermore, for example, a conductive film that connects a gate electrode and a gate wiring and is made of a material different from that of the gate electrode or the gate wiring may also be called a gate electrode or a gate wiring.

Note that the gate terminal refers to a part of a gate electrode (a region, a conductive film, a wiring, etc.) or a part electrically connected to a gate electrode (a region, a conductive film, a wiring, etc.).

In addition, when a wiring is referred to as a gate wiring, a gate line, a gate signal line, a scanning line, a scanning signal line, or the like, the gate of a transistor may not be connected to the wiring. In this case, the gate wiring, the gate line, the gate signal line, the scanning line, or the scanning signal line may mean a wiring formed in the same layer as the gate of a transistor, a wiring formed from the same material as the gate of a transistor, or a wiring formed at the same time as the gate of a transistor. Examples include a storage capacitor wiring, a power supply line, a reference potential supply wiring, and the like.

The source includes a source region, a source electrode, and a source wiring (a source line, a source signal line,
The source region refers to the whole or a part of the semiconductor device including the P-type impurity (such as boron or gallium) or N-type impurity (such as phosphorus or arsenic). Therefore, a region that contains only a small amount of P-type or N-type impurity, a so-called LDD (Lightly Doped Drain) region,
It is not included in the source region. The source electrode is a conductive layer formed of a material different from the source region and electrically connected to the source region. However, the source electrode may also be called the source electrode including the source region. The source wiring is a wiring for connecting the source electrodes of each transistor, a wiring for connecting the source electrodes of each pixel, or a wiring for connecting the source electrode to another wiring.

However, there is a portion that functions as both a source electrode and a source wiring (
Such a portion (region, conductive film, wiring, etc.) may be called either a source electrode or a source wiring. In other words, there are also regions where the source electrode and the source wiring cannot be clearly distinguished. For example, when a part of the extended source wiring overlaps with the source region, that portion (region, conductive film, wiring, etc.) may be called either a source electrode or a source wiring.
The portion (region, conductive film, wiring, etc.) functions as a source wiring, but also functions as a source electrode. Therefore, such a portion (region, conductive film, wiring, etc.) may be called either a source electrode or a source wiring.

Note that a portion (region, conductive film, wiring, etc.) that is made of the same material as the source electrode and is connected to the source electrode to form the same island, and a portion (region, conductive film, wiring, etc.) that connects source electrodes to each other may also be called a source electrode. Furthermore, a portion that overlaps with the source region may also be called a source electrode. Similarly, a region that is made of the same material as the source wiring and is connected to the source electrode to form the same island may also be called a source electrode.
It may be called source wiring. Strictly speaking, such a part (region, conductive film, wiring, etc.) may not have the function of connecting to another source electrode. However, due to the specifications at the time of manufacture, there are parts (region, conductive film, wiring, etc.) that are formed of the same material as the source electrode or source wiring and are connected to the source electrode or source wiring. Therefore, such parts (region, conductive film, wiring, etc.) may also be called source electrodes or source wiring.

In addition, for example, a conductive film that connects a source electrode and a source wiring and is made of a material different from the source electrode or the source wiring may also be called a source electrode or a source wiring.

The source terminal refers to a part of the source region, the source electrode, or a portion electrically connected to the source electrode (a region, a conductive film, a wiring, or the like).

In addition, when referring to a source wiring, a source line, a source signal line, a data line, a data signal line, etc.,
There are cases where the source (drain) of a transistor is not connected to the wiring. In this case, the source wiring, source line, source signal line, data line, and data signal line may mean wiring formed in the same layer as the source (drain) of a transistor, wiring formed from the same material as the source (drain) of a transistor, or wiring formed at the same time as the source (drain) of a transistor. Examples include storage capacitor wiring, power supply wiring, and reference potential supply wiring.

The drain is the same as the source.

Note that a semiconductor device refers to a device having a circuit including a semiconductor element (transistor, diode, thyristor, etc.). Furthermore, any device that can function by utilizing semiconductor characteristics may be called a semiconductor device. Alternatively, a device having a semiconductor material is called a semiconductor device.

The display element includes an optical modulation element, a liquid crystal element, a light emitting element, an EL element (organic EL element,
This refers to, but is not limited to, an inorganic EL element or an EL element containing organic and inorganic materials), an electron emission element, an electrophoretic element, a discharge element, an optical reflection element, an optical diffraction element, a digital micromirror device (DMD), etc.

The display device refers to a device having a display element. The display device may include a plurality of pixels including a display element. The display device may include a peripheral driver circuit for driving the plurality of pixels. The peripheral driver circuit for driving the plurality of pixels may be formed on the same substrate as the plurality of pixels. The display device may include a peripheral driver circuit arranged on a substrate by wire bonding, bumps, or the like, so-called an IC chip connected by chip-on-glass (COG), or an IC chip connected by TAB or the like.
The display device may include a flexible printed circuit (FPC) on which an IC chip, a resistive element, a capacitive element, an inductor, a transistor, etc. are attached. The display device may include a printed wiring board (PWB) on which an IC chip, a resistive element, a capacitive element, an inductor, a transistor, etc. are attached, which is connected via a flexible printed circuit (FPC) or the like.
The display device may include an optical sheet such as a polarizing plate or a retardation plate. The display device may include an illumination device, a housing, an audio input/output device, an optical sensor, etc. Here, an illumination device such as a backlight unit may include a light guide plate, a prism sheet, a diffusion sheet, a reflection sheet, a light source (LED, cold cathode fluorescent lamp, etc.), a cooling device (water-cooled type,
Air-cooled type) may be included.

The illumination device refers to a device that includes a backlight unit, a light guide plate, a prism sheet, a diffusion sheet, a reflective sheet, a light source (LED, cold cathode tube, hot cathode tube, etc.), a cooling device, etc.

Note that the light-emitting device refers to a device having a light-emitting element, etc. When a light-emitting element is used as a display element, the light-emitting device is a specific example of a display device.

The reflecting device refers to a device having a light reflecting element, a light diffractive element, a light reflecting electrode, and the like.

Note that the liquid crystal display device refers to a display device having a liquid crystal element.
There are direct-view, projection, transmissive, reflective, and semi-transmissive types.

The driving device refers to a device having a semiconductor element, an electric circuit, and an electronic circuit. For example, a transistor that controls the input of a signal from a source signal line into a pixel (sometimes called a selection transistor, a switching transistor, etc.), a transistor that supplies a voltage or current to a pixel electrode, a transistor that supplies a voltage or current to a light-emitting element, etc. are examples of the driving device. Furthermore, a circuit that supplies a signal to a gate signal line (sometimes called a gate driver, a gate line driving circuit, etc.), a circuit that supplies a signal to a source signal line (sometimes called a source driver, a source line driving circuit, etc.), etc. are examples of the driving device.

Note that the display device, the semiconductor device, the lighting device, the cooling device, the light-emitting device, the reflecting device, the driving device, and the like may overlap with one another. For example, a display device may include a semiconductor device and a light-emitting device. Alternatively, a semiconductor device may include a display device and a driving device.

In addition, when it is explicitly stated that B is formed on A, or B is formed on A, it is not limited to B being formed directly on A. It also includes the case where B is not in direct contact with A, that is, the case where another object is interposed between A and B.
Here, A and B are assumed to be objects (for example, a device, an element, a circuit, a wiring, an electrode, a terminal, a conductive film, a layer, etc.).

Therefore, for example, when it is explicitly stated that layer B is formed on layer A (or on layer A), this includes the case where layer B is formed directly on layer A, and the case where another layer (e.g. layer C or layer D, etc.) is formed directly on layer A, and layer B is formed directly on the other layer. The other layer (e.g. layer C or layer D, etc.) may be a single layer or multiple layers.

The same applies to cases where it is explicitly stated that B is formed above A, and this does not necessarily mean that B is directly on top of A, but also includes cases where another object is present between A and B. Therefore, for example, if layer B is formed above layer A,
This includes cases where layer B is formed directly on layer A, and cases where another layer (e.g., layer C or layer D) is formed directly on layer A, and layer B is formed directly on the other layer. The other layer (e.g., layer C or layer D) may be a single layer or multiple layers.

In addition, when it is explicitly stated that B is formed directly on A, this includes the case where B is formed directly on A, and does not include the case where another object is interposed between A and B.

The same applies when B is placed below A, or B is placed below A.

In addition, when something is explicitly described as singular, it is preferable that it is singular. However, this is not limited, and it is also possible to use plural. Similarly, when something is explicitly described as plural, it is preferable that it is plural. However, this is not limited, and it is also possible to use singular.

According to the present invention, it is possible to improve the viewing angle characteristics compared to the conventional art while maintaining the performance of the display device. Alternatively, according to the present invention, it is possible to provide a highly reliable display device. Alternatively, according to the present invention, it is possible to provide a display device with high contrast. Alternatively, according to the present invention, it is possible to provide a lightweight display device. Alternatively, according to the present invention, it is possible to provide a display device with a small size. Alternatively, according to the present invention, it is possible to provide a display device with high brightness. Alternatively, according to the present invention, it is possible to provide a display device with low power consumption. Alternatively, according to the present invention, it is possible to provide a display device with a high aperture ratio. Alternatively, according to the present invention, it is possible to provide a display device with low manufacturing costs.

FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. 1A and 1B are diagrams illustrating a voltage dividing element included in a pixel circuit of a display device of the present invention. 1A to 1C are diagrams illustrating a display device of the present invention. FIG. 2 is a diagram illustrating an example of a top surface layout of a pixel of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating an example of a top surface layout of a pixel of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. 2 is a diagram illustrating a pixel circuit of a display device of the present invention. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG.

(Embodiment 1)
In this embodiment mode, the configuration and operation of a pixel circuit included in a liquid crystal display device of the present invention will be described with reference to the drawings. The pixel circuit of the liquid crystal display device of the present invention has a configuration in which a plurality of liquid crystal elements are included in one pixel, and voltages applied to the liquid crystal elements are made different. Specifically, one or both of a capacitance element and a resistance element are provided connected to the liquid crystal element to make the voltages applied to the liquid crystal element different.

However, the display element is not limited to a liquid crystal element, and various display elements (e.g., light-emitting elements (EL
Elements (EL elements containing organic and inorganic materials, organic EL elements, inorganic EL elements, electron emission elements), electrophoretic elements, etc.) can be used.

There are various operation modes of liquid crystal to which the present embodiment can be applied. For example,
(Twisted Nematic) mode, IPS (In-Plane-Switch
Fringe Field Switching (FFS) mode, M
VA (Multi-domain Vertical Alignment) mode, P
VA (Patterned Vertical Alignment), CPA (Con
Tinuous Pinwheel Alignment mode, ASM (Axial
ly Symmetric aligned Micro-cell) mode, OCB (
Optical Compensated Birefringence) mode, FL
C (Ferroelectric Liquid Crystal) mode, AFLC (
However, there is no limitation to this. The liquid crystal to which the CPA mode is applied is ASV (Advanced Liquid Crystal).
It is sometimes called LC (Substrate-less Liquid Crystal) (Substrate-less Liquid Crystal: 3D Super View).

FIG. 1A shows an example of the configuration of one pixel in a liquid crystal display device of the present invention.
The liquid crystal display device includes a first switch 101 , a second switch 102 , a first liquid crystal element 103 , a second liquid crystal element 104 , a third liquid crystal element 105 , a first capacitor element 106 , and a second capacitor element 107 .

The first wiring 108 is connected to the first electrode of the first liquid crystal element 103 and the first electrode of the first capacitor element 106 through the first switch 101.
The first electrode of the liquid crystal element 104 and the first electrode of the second capacitor element 107 are connected via the second switch 102. The second electrode of the first capacitor element 106 is connected to the first electrode of the second capacitor element 107 via the second switch 102.
The second electrode of the third liquid crystal element 107 is connected to a first electrode of the third liquid crystal element 105 .

The second electrodes of the first liquid crystal element 103 , the second liquid crystal element 104 and the third liquid crystal element 105 are connected to a common electrode 111 .

The first wiring 108 and the second wiring 109 function as signal lines. Therefore, an image signal is usually supplied to the first wiring 108 and the second wiring 109. However, this is not limited to this. A constant signal may be supplied regardless of the image.

The first switch 101 and the second switch 102 are not particularly limited as long as they function as switches. For example, transistors can be used. Hereinafter, a case where transistors are used as the first switch 101 and the second switch 102 will be described (
(See FIG. 1B). When a transistor is used, its polarity may be P-channel or N-channel. For example, when the gate-source voltage (V _gs ) of an N-channel transistor exceeds the threshold voltage (V _th ), the source-drain is brought into a conductive state. The drain-source voltage of a transistor is denoted as V _ds .

1B shows a case where an N-channel transistor is used as a switch, and FIG. 1C shows a case where a P-channel transistor is used as a switch. In FIG. 1B and FIG. 1C, a first switch 101N (or a first switch 101P) and a second switch 10
The gate of 2N (or the second switch 102P) is connected to the third wiring 110. The third wiring 110 functions as a scan line.

It is to be noted that two scanning lines may be provided as shown in Fig. 49. The circuit shown in Fig. 49 is similar to the circuit shown in Fig. 8 except that two signal lines are provided.

Note that although the case where P-channel transistors are used as switches is shown only in Fig. 1, this is not limiting. In other figures as well, at least one of the transistors can be replaced with a P-channel transistor.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

A video signal is input to the first wiring 108 and the second wiring 109. A scanning signal is input to the third wiring 110. The scanning signal is a digital voltage signal of H level or L level. When the first switch 101 is an N-channel transistor, the H level of the scanning signal
The high level of the scanning signal is a potential that can turn on the first switch 101 and the second switch 102, and the low level of the scanning signal is a potential that can turn off the first switch 101 and the second switch 102. Alternatively, when the first switch 101 and the second switch 102 are P-channel transistors, the high level of the scanning signal is a potential that can turn off the first switch 101 and the second switch 102, and the low level of the scanning signal is a potential that can turn off the first switch 101 and the second switch 102.
02 can be turned on. The video signal is an analog voltage. However, the present invention is not limited to this, and the video signal may be a digital voltage. Alternatively, the video signal may be a current. The current of the video signal may be either analog or digital. It is desirable that the video signal has a potential lower than the H level of the scanning signal and higher than the L level of the scanning signal.

The operation of the pixel 100 will be described separately for a case where the first switch 101 and the second switch 102 are on and a case where the first switch 101 and the second switch 102 are off.

When the first switch 101 is on, the first wiring 108 is electrically connected to the first electrode (pixel electrode) of the first liquid crystal element 103 and the first electrode of the first capacitor element 106. When the second switch 102 is on, the second wiring 109 is electrically connected to the first electrode (pixel electrode) of the second liquid crystal element 104 and the first electrode of the second capacitor element 107. Therefore, a video signal is transmitted from the first wiring 108 to the first liquid crystal element 103.
The video signal is input to the first electrode (pixel electrode) of the second liquid crystal element 104 and the first electrode of the first capacitor element 106 from the second wiring 109. Alternatively, the video signal is input to the first electrode (pixel electrode) of the second liquid crystal element 104 and the first electrode of the second capacitor element 107 from the second wiring 109. Therefore, the potential _V103 of the signal input to the first liquid crystal element 103 is approximately equal to the potential input from the first wiring 108,
The potential _V104 of the signal input to the third liquid crystal element 104 is approximately equal to the potential input from the second wiring 109. The potential _V105 of the first electrode of the third liquid crystal element 105 is a value obtained by dividing the potential between the first capacitor 106 and the second capacitor 107. Here, the capacitance value of the first capacitor 106 is _C106 , and the capacitance value of the second capacitor 107 is _C107 . Then, _V105 =ΔV× _C107 /( _C106 + _C107 )+ _V103 . Here,
ΔV=V ₁₀₄ −V ₁₀₃ , where each capacitance element has no initial charge.
Here, when C ₁₀₆ and C ₁₀₇ are the same size, V ₁₀₅ is equal to V ₁₀₃ and V _10
4. Here, when the potential of the common electrode is 0, the voltage applied to the first liquid crystal element is expressed as V ₁₀₃ , the voltage applied to the second liquid crystal element is expressed as V ₁₀₄ , and the voltage applied to the third liquid crystal element is expressed as V ₁₀₅ = (V ₁₀₃ + V ₁₀₄ )/2. By making the potential of the signal input from the first wiring 108 and the potential of the signal input from the second wiring 109 different, the voltage applied to each liquid crystal element can be made different, and each alignment state can be made different. Therefore, it is preferable that the signal input from the first wiring 108 and the signal input from the second wiring 109 have different potentials.

In this way, by supplying two signals with different potentials and using a capacitive element, it is possible to divide the voltage inside the pixel and generate a voltage (third voltage) that is intermediate between the two signals.
Then, by applying the third voltage to the third liquid crystal element 105, the liquid crystal can be easily controlled. Furthermore, the third voltage is a voltage between the voltage applied to the first liquid crystal element 103 and the voltage applied to the second liquid crystal element 104. Therefore, no matter what kind of gradation is to be displayed, an appropriate gradation can be displayed. Furthermore, no matter whether the polarity of the image signal is positive (when the image signal is higher than the common electrode) or negative (when the image signal is lower than the common electrode), an appropriate gradation can be displayed.

Furthermore, the third voltage can be generated to control the third liquid crystal element 105 while suppressing an increase in the number of scanning lines, signal lines, transistors, etc. This makes it possible to increase the aperture ratio.
Power consumption can be reduced. In addition, since the layout of pixels can be arranged with a margin, defects such as short circuits that may occur due to dust generated in the manufacturing process can be reduced, and the yield is improved. As a result, manufacturing costs can be reduced. In addition, since the third liquid crystal element 105 can be controlled without providing new wiring that functions as a signal line for controlling the third liquid crystal element, the number of connection points between the glass substrate and an external driver circuit does not increase. As a result, high reliability can be maintained.

It is preferable that the capacitance values of the first capacitor 106 and the second capacitor 107 are approximately equal. When the capacitance values of the two capacitors are approximately equal, the divided potential becomes an intermediate value of the potentials supplied to the two capacitors. If there is a difference in the capacitance values, the potential will be biased toward one of the potentials, and the liquid crystal element cannot be controlled uniformly. Therefore, it is preferable that the capacitance value of the first capacitor 106 and the capacitance value of the second capacitor 107 are approximately equal. However, this is not limiting.

When the first switch 101 is off, the first wiring 108 is electrically disconnected from the first electrode (pixel electrode) of the first liquid crystal element 103 and the first electrode of the first capacitor 106. When the second switch 102 is off, the second wiring 109 is electrically disconnected from the first electrode (pixel electrode) of the second liquid crystal element 104 and the first electrode of the second capacitor 107. Therefore, the first electrode of the first liquid crystal element 103 and the first capacitor 106 are electrically disconnected from each other.
The first electrode of the third liquid crystal element 105, the first electrode of the second liquid crystal element 104, and the first electrode of the second capacitor element 107 are in a floating state. The third liquid crystal element 105 is connected to the first liquid crystal element 103 via the first capacitor element 106. However, due to the law of conservation of charge, the charge stored in the third liquid crystal element 105 does not leak to the first liquid crystal element 103. Similarly,
The third liquid crystal element 105 is connected to the second liquid crystal element 104 via the second capacitor element 107. However, due to the law of conservation of charge, the charge stored in the third liquid crystal element 105 is
There is no leakage to the second liquid crystal element 104. Therefore, the first to third liquid crystal elements hold the potential of the signal that was input immediately before.

The first liquid crystal element 103, the second liquid crystal element 104, and the third liquid crystal element 105 have transmittances according to a video signal.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

Each liquid crystal element may be divided into a plurality of elements. For example, the third liquid crystal element 105 may be divided into two elements, a third liquid crystal element 105a and a fourth liquid crystal element 105b, as shown in FIG.
Similarly, the first liquid crystal element 103 and the second liquid crystal element 104 may also be divided into a plurality of pieces. This also applies to the figures other than FIG.

1 and 11, when the first switch 101 and the second switch 102 are transistors, their gates are connected to a third wiring 110.
The gate of the first switch 101 and the gate of the second transistor may be connected to different wirings (see FIG. 49). The same applies to figures other than FIG. 1 and FIG. 11.

1 and 11, the first switch 101 and the second switch 102 are connected to different signal lines, but this is not limited to this. As shown in Fig. 8 or 17, the first switch 101 and the second switch 102 may be connected to the same wiring. This also applies to figures other than Fig. 1 and 11.

In addition, the liquid crystal element shows a voltage retention characteristic, but the retention rate is not 100%. Therefore, in FIG. 1 and FIG. 11, a capacitive element (hereinafter simply referred to as a retention capacitance) that becomes a retention capacitance may be arranged in each liquid crystal element to retain the voltage. The retention capacitance may be arranged for all liquid crystal elements, or may be arranged only for some liquid crystal elements. The retention capacitance is arranged between each pixel electrode and a wiring that functions as a capacitance line connected thereto. Each retention capacitance may be connected to a different capacitance line, or may be connected to the same capacitance line. Alternatively, some retention capacitances may be connected to the same capacitance line, and other retention capacitances may be connected to different capacitance lines. In addition, the capacitance line may be shared with another pixel. For example, it can be shared between a pixel in the previous row and a pixel in the next row. By sharing the capacitance line between different pixels, the number of wirings can be reduced, and the aperture ratio can be improved. In addition, the capacitance line may be shared with a scanning line. By sharing the capacitance line with the scanning line, the number of wirings can be reduced, and the aperture ratio can be improved. When the capacitance line is shared with the scanning line, it is desirable to use the scanning line of the adjacent row of pixels (the pixel in the previous row). This is because the signal selection for the i-1th row (the row previous to the i-1th row) has already been completed when the pixel in the i-th row is selected. Note that, when the liquid crystal is IPS or FFS, the common electrode is disposed on the substrate on which the transistors are formed. Therefore, the capacitance line may be shared with the common electrode. Sharing the capacitance line with the common electrode makes it possible to reduce the number of wirings and improve the aperture ratio. Note that,
The storage capacitor may be divided into a plurality of parts, similarly to the liquid crystal element in Fig. 11. This also applies to figures other than Fig. 1 and Fig. 11.

Next, a display device having the pixel 100 shown in FIG. 1 will be described with reference to FIG.

The display device includes a signal line driver circuit 1911, a scanning line driver circuit 1912, and a pixel portion 1913. The pixel portion 1913 includes first wirings S1_1 to Sm_1, second wirings S1_2 to Sm_2, and a scanning line driver circuit 1912. The first wirings S1_1 to Sm_1, second wirings S1_2 to Sm_2, and a scanning line driver circuit 1912 are arranged to extend in the column direction from the signal line driver circuit 1911.
The pixel 1914 has third wirings G1 to Gn arranged extending in the row direction from the pixel 1912, and pixels 1914 arranged in a matrix. The first and second wirings function as signal lines. The third wiring functions as a scanning line. Each pixel 1914 is connected to the first wiring Sj_1 (signal line S1
1, a second wiring Sj_2 (one of the signal lines S1_2 to Sm_2), and a third wiring Gi (one of the scanning lines G1 to Gn).

Note that the first wiring Sj_1, the second wiring Sj_2, and the third wiring Gi correspond to the first wiring 108, the second wiring 109, and the third wiring 110 in FIG. 1, respectively.

When a row of pixels to be operated is selected by a signal output from the scanning line driver circuit 1912, each pixel belonging to the same row is selected at the same time. A video signal output from the signal line driver circuit 1911 is written to the pixels of the selected row. At this time, a potential corresponding to the luminance data of each pixel is supplied to the first wirings S1_1 to Sm_1 and the second wirings S1_2 to Sm_2.

For example, when the data write period for the i-th row is completed, a signal is written to the pixels in the (i+1)-th row. Then, the pixels in the i-th row for which the data write period has been completed have a transmittance according to the signal.

Note that a plurality of signal line driver circuits 1911 or a plurality of scanning line driver circuits 1912 may be arranged. For example, the first wiring Sj_1 (one of the signal lines S1_1 to Sm_1)
The pixel portion 191 may be driven by a first signal line driver circuit, and the second wiring Sj_2 (one of the signal lines S1_2 to Sm_2) may be driven by a second signal line driver circuit.
For example, the first signal line driver circuit may be disposed on one side of the main surface of the substrate, the second signal line driver circuit may be disposed on the other opposite side, and the pixel section 1 may be disposed in the region between the two signal line driver circuits.
913 may be placed.

In order to suppress deterioration of the liquid crystal material and display unevenness such as flickering, it is preferable to use an inversion drive in which the polarity of the voltage applied to the pixel electrode is inverted with respect to the potential of the common electrode (common potential) in the liquid crystal capacitance at regular intervals.
When the potential of the pixel electrode is higher than that of the common electrode, a positive voltage is applied to the liquid crystal capacitance, and when the potential of the counter electrode is higher than that of the pixel electrode, a negative voltage is applied to the liquid crystal capacitance. In addition, when a positive voltage is applied to the liquid crystal capacitance, an image signal input from a signal line is expressed as a positive signal, and when a negative voltage is applied, an image signal input from a signal line is expressed as a negative signal. Examples of inversion driving include frame inversion driving, source line inversion driving, gate line inversion driving, and dot inversion driving.

Frame inversion driving is a driving method in which the polarity of the voltage applied to the liquid crystal capacitance is inverted every frame period. Note that one frame period corresponds to a period during which an image for one pixel is displayed, and although there is no particular limit to this period, it is preferable that the period be at least 1/60 seconds or less so that the person viewing the image does not perceive flickering.

Source line inversion driving is a driving method in which the polarity of the voltage applied to the liquid crystal capacitance of pixels connected to the same signal line is inverted with respect to the liquid crystal capacitance of pixels connected to an adjacent signal line, and frame inversion is performed for each pixel. Meanwhile, gate line inversion driving is a driving method in which the polarity of the voltage applied to the liquid crystal capacitance of pixels connected to the same wiring functioning as a scanning line is inverted with respect to the liquid crystal capacitance of pixels connected to an adjacent scanning line,
Furthermore, this is a driving method in which frame inversion is performed for each pixel.

Moreover, dot inversion driving is a driving method in which the polarity of the voltage applied to the liquid crystal capacitance between adjacent pixels is inverted, and is a driving method that combines source line inversion driving and gate line inversion driving.

By the way, the above-mentioned frame inversion driving, source line inversion driving, gate line inversion driving,
When dot inversion driving or the like is adopted, the width of the potential required for the image signal written to the signal line becomes twice as large as when inversion driving is not performed. Therefore, in order to solve this problem, when using frame inversion driving or gate line inversion driving, common inversion driving, which further inverts the potential of the opposing electrode, may be adopted.

Common inversion driving is a driving method in which the potential of the common electrode is changed in synchronization with the reversal of polarity applied to the liquid crystal capacitance, and by performing common inversion driving, the potential width required for the image signal written to the signal line can be reduced.

Furthermore, one pixel may have a plurality of the pixel configurations described above. For example, one pixel may have a plurality of sub-pixels, and the gradation of one pixel may be expressed using these sub-pixels. Signal lines connected to different sub-pixels may be shared between the sub-pixels. It is also possible to apply different voltages to the liquid crystal capacitances belonging to the respective sub-pixels by supplying different potentials to the capacitance lines connected to the sub-pixels. In this way,
By utilizing the difference in the orientation of the liquid crystal in each sub-pixel, it is possible to further improve the viewing angle.

Although the storage capacitor is not clearly shown in FIG. 1, it is desirable to arrange the storage capacitor as described above. By arranging the storage capacitor, the influence of leakage current of the liquid crystal element can be reduced, and the potential can be easily maintained. In addition, the influence of switching noise such as feedthrough can be reduced. Therefore, as an example of a case where a storage capacitor is illustrated, a case where a storage capacitor is arranged in the circuit of FIG. 1 is shown in FIG. 16.

In FIG. 16, a pixel 400 includes a first switch 401, a second switch 402, and
A first liquid crystal element 403, a second liquid crystal element 404, a third liquid crystal element 405, a first capacitor element 406, a second capacitor element 407, a third capacitor element 408, and a fourth capacitor element 409.
09 and a fifth capacitor 417.

The first wiring 410 is connected to the first electrode of the first liquid crystal element 403, the first electrode of the first capacitor 406, and the first electrode of the second capacitor 407 through the first switch 401. The second wiring 411 is connected to the first electrode of the second liquid crystal element 404, the first electrode of the third capacitor 408, and the first electrode of the fourth capacitor 409 through the second switch 402. The second electrode of the first capacitor 406 and the second electrode of the third capacitor 408 are connected to the first electrode of the third liquid crystal element 405 and the first electrode of the fifth capacitor 417. The second electrode of the second capacitor 407 is connected to the fourth wiring 413, and the second electrode of the fourth capacitor 409 is connected to the fifth wiring 414. The fifth capacitor 417
The second electrode of the second electrode is connected to a sixth wiring 415 .

The second electrodes of the first liquid crystal element 403 , the second liquid crystal element 404 , and the third liquid crystal element 405 are connected to a common electrode 416 .

The first wiring 410 and the second wiring 411 function as signal lines.
An image signal is usually supplied to the first wiring 410 and the second wiring 411. However, this is not limiting. A constant signal may be supplied regardless of the image. The third wiring 412 functions as a scan line. The fourth wiring 413, the fifth wiring 414, and the sixth wiring 415 function as capacitance lines.

The first switch 401 and the second switch 402 are not particularly limited as long as they function as switches. For example, transistors can be used. Hereinafter, a case in which transistors are used as the first switch 401 and the second switch 402 will be described.
When a transistor is used, the polarity may be either P-channel type or N-channel type.

FIG. 16B shows a case where an N-channel transistor is used as a switch.
In (B), the gates of the first switch 401N and the second switch 402N are connected to a third wiring 412. The third wiring 760 functions as a scan line.

As shown in FIG. 16, a storage capacitor may be arranged in all the liquid crystal elements, but this is not limited thereto. For example, as shown in FIG. 7, a storage capacitor may be arranged in only some of the liquid crystal elements. Each storage capacitor may be connected to a different capacitance line, or may be connected to the same capacitance line, or some may be connected to the same capacitance line and some may be connected to different capacitance lines. The capacitance line may be shared with another pixel. For example, it may be shared by a pixel in the previous row and a pixel in the next row. Sharing a capacitance line between different pixels can reduce the number of wirings and improve the aperture ratio. Alternatively, the capacitance line may be shared with a scanning line. Sharing a capacitance line with a scanning line can reduce the number of wirings and improve the aperture ratio. When a capacitance line is shared with a scanning line, it is desirable to use the scanning line of an adjacent pixel (pixel in the previous row). This is because the i-1th row (the previous row) has already finished signal selection when selecting a pixel in the ith row. When the liquid crystal is an IPS, FFS, or the like, the common electrode is arranged on a substrate on which a transistor is formed. Therefore, the capacitance line may be used in common with the common electrode, which can reduce the number of wirings and improve the aperture ratio.

It is preferable that a constant potential is supplied to the capacitance line. However, this is not limiting. For example, in FIG. 7, a signal that periodically changes multiple times may be supplied to each capacitance line, that is, the fourth wiring 413 and the fifth wiring 414, during one frame period. In addition, mutually inverted signals may be applied to each capacitance line, that is, the fourth wiring 413 and the fifth wiring 414. As a result, the effective voltage applied to the first liquid crystal element 404, the second liquid crystal element 403, etc. can be changed.

In addition, although there are two wirings functioning as capacitance lines in Fig. 16, this is not limiting. The capacitance lines can be combined into one. Furthermore, the common electrode and the capacitance line can be shared. This is because there are no particular limitations on the common electrode and the capacitance line other than the fact that both must be kept at the same potential. Fig. 50 shows a diagram in which the capacitance lines are combined into one and the common electrode and the capacitance line are shared. Fig. 50 has the same effect as Fig. 16.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

In the above description, the transistors used as the first switch and the second switch are connected to different signal lines in other figures such as FIG. 1, but are not limited to this. They may be connected to the same signal line. For example, FIG. 8 shows an example in which the two signal lines in FIG. 1 are combined into one, and multiple scanning lines are provided. FIG. 17 shows an example in which the scanning lines in FIG. 8 are combined into one.

In Fig. 8 and Fig. 17, it is also possible to arrange the storage capacitors in different liquid crystal elements as in Fig. 7 and Fig. 16. As an example, Fig. 18 and Fig. 19 show a case where storage capacitors are arranged in the first and second liquid crystal elements in the same manner as in Fig. 7.

Therefore, the contents described with reference to FIGS. 1 and 7 can also be applied to FIGS. 8, 16, 17 and 18.

In FIG. 8, a pixel 450 includes a first switch 451, a second switch 452, a first liquid crystal element 453, a second liquid crystal element 454, a third liquid crystal element 455, a first capacitor element 456, and a second capacitor element 457.

The first wiring 458 is connected to the first electrode of the first liquid crystal element 453 and the first electrode of the first capacitor element 456 through the first switch 451.
8, a first electrode of the second liquid crystal element 454, and a first electrode of the second capacitor element 457 are
The third liquid crystal element 455 is connected to a first electrode of the third liquid crystal element 455 via a second switch 452. A second electrode of the first capacitor 456 and a second electrode of the second capacitor 457 are connected to a first electrode of the third liquid crystal element 455.

A transistor can be used as the switch.
The gate of the second switch 452N is connected to the second wiring 459.
4. The signal line 460 is connected to the signal line 460.

Second electrodes of the first liquid crystal element 453 , the second liquid crystal element 454 , and the third liquid crystal element 455 are connected to a common electrode 461 .

The first wiring 458 functions as a signal line. Therefore, an image signal is usually supplied to the first wiring 458. However, this is not limited to this. A constant signal may be supplied regardless of the image. The second wiring 459 and the third wiring 460 function as scan lines.

8 and 18 will be considered first. First, an active signal is supplied to the third wiring 460, and the second switch 452 is turned on. Here, the active signal means a signal that can turn on the second switch 452. When the second switch 452 is turned on, a video signal is supplied from the first wiring 458 to the first electrode (pixel electrode) of the second liquid crystal element 454 and the first electrode of the second capacitor element 457.

Next, the second switch 452 is turned off, an active signal is supplied to the second wiring 459, and the first switch 451 is turned on.
The potential of the video signal supplied from the first wiring 458 is different from that when the second switch 452 is turned on. The potentials of the video signal supplied from the first wiring 458 are different from those when the second switch 452 is turned on. By using different potentials, different voltages can be supplied to the liquid crystal elements, and the viewing angle can be improved.

When the first switch 451 is on, the third liquid crystal element 455 is capacitively coupled to the pixel electrode of the first liquid crystal element 453 through the first capacitor 456. Therefore, the potential of the pixel electrode of the third liquid crystal element 455 changes according to the voltage supplied from the first wiring 458 when the first switch 451 is on.

Similarly, when the first switch 451 is on, the second liquid crystal element 454 is capacitively coupled to the pixel electrode of the first liquid crystal element 453 through the first capacitor 456 and the second capacitor 457. Therefore, the potential of the pixel electrode of the second liquid crystal element 454 changes according to the voltage supplied from the first wiring 458 when the first switch 451 is on.

Next, the first switch 451 is turned off, and the potential of each liquid crystal element is maintained.
By operating in this way, it is possible to make the voltage applied to each liquid crystal element different. As a result, it is possible to widen the viewing angle. However, the driving method is not limited to this. It is possible to drive in various ways, such as the timing of turning on and off each transistor, the potential of the signal line, etc.

In addition, in FIG. 18, it is desirable that a constant potential is supplied to each capacitance line.
However, the present invention is not limited to this. For example, a signal that changes periodically multiple times may be supplied to each capacitance line, i.e., the first capacitance line and the second capacitance line, during one frame period.
Mutually inverted signals may be applied to each capacitance line, that is, the first capacitance line and the second capacitance line. As a result, the effective voltage applied to the first liquid crystal element 453, the second liquid crystal element 454, etc. can be changed. By operating in this way, the potentials of the liquid crystal elements can be made different. As a result, the viewing angle can be widened.

Next, consider the operations shown in Figures 17 and 19.

An active signal is supplied to the second wiring 459, and the first switch 451 and the second switch 452 are turned on. Then, the first electrode (pixel electrode) of the first liquid crystal element 453,
A video signal is supplied from a first wiring 458 to a first electrode of the first capacitor 456 , a first electrode (pixel electrode) of the second liquid crystal element 454 , and a first electrode of the second capacitor 457 .

At this time, when transistors are used for the first switch 451 and the second switch 452, an on-resistance is generated. The on-resistance of the first switch 451 is desirably higher than the on-resistance of the second switch 452. A high on-resistance of a transistor means that the ratio of the channel width to the channel length L (W/L) is small. In this way, by increasing the on-resistance of the transistor, the potential of the pixel electrode of each liquid crystal element is determined by the balance of leakage currents of each capacitance element and each storage capacitance. Then, different voltages can be applied to each liquid crystal element, and the viewing angle can be improved. However, this is not limited, and the first switch 451 and the second switch 452 can also have approximately the same on-resistance.

Next, the first switch 451 and the second switch 452 are turned off, and the voltage applied to each liquid crystal element is maintained.

By operating in this way, it is possible to make the voltage applied to each liquid crystal element different. As a result, it is possible to widen the viewing angle. However, the driving method is not limited to this. It is possible to drive in various ways, such as the timing of turning on and off each transistor, the potential of the signal line, etc.

In addition, in FIG. 19, it is desirable that a constant potential is supplied to each capacitance line.
However, this is not limiting. For example, during one frame period, a signal that changes periodically multiple times may be supplied to each capacitance line, that is, the first capacitance line 463 and the second capacitance line 465. Furthermore, mutually inverted signals may be applied to each capacitance line, that is, the first capacitance line 463 and the second capacitance line 465. As a result, the first liquid crystal element 453 and the second liquid crystal element 466 may be inverted.
By operating in this manner, the potential of each liquid crystal element can be made different, thereby widening the viewing angle.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

Fig. 2 shows an example of a pixel circuit configuration of a liquid crystal display device of the present invention, which is different from that shown in Fig. 1. A pixel 150 includes a first switch 151, a second switch 152, a first liquid crystal element 153, a second liquid crystal element 154, a third liquid crystal element 155, a first capacitor 156, a second capacitor 157, and a third capacitor 161.

The first wiring 158 is connected to a first electrode of the first liquid crystal element 153 and a first electrode of the first capacitor 156 through a first switch 151. The second wiring 159 is connected to a first electrode of the second liquid crystal element 154 and a first electrode of the second capacitor 157 through a second switch 152.
57 and a first electrode of the third capacitor element 161.
The second electrode of the third liquid crystal element 61 is connected to the first electrode of the third liquid crystal element 155 .

The second electrodes of the first liquid crystal element 153, the second liquid crystal element 154, and the third liquid crystal element 155 are connected to a common electrode.

The first wiring 158 and the second wiring 159 function as signal lines. Therefore, image signals are usually supplied to the first wiring 158 and the second wiring 159. However, this is not limited to this. A constant signal may be supplied regardless of the image. The third wiring 160 functions as a scan line.

The first switch 151 and the second switch 152 are not particularly limited as long as they function as switches. For example, transistors can be used. Hereinafter, a case in which transistors are used as the first switch 151 and the second switch 152 will be described.
When a transistor is used, the polarity may be either P-channel type or N-channel type.

FIG. 2B shows a case where an N-channel transistor is used as a switch.
), gates of a first switch 151N and a second switch 152N are connected to a third wiring 110. The third wiring 160 functions as a scan line.

As in FIG. 1, in FIG. 2 as well, two scanning lines may be provided as shown in FIG.
It is also possible to use a P-channel transistor as the switch.

A video signal is input to the first wiring 158 and the second wiring 159. A scanning signal is input to the third wiring 160. The scanning signal is an H-level or L-level digital voltage signal. When the first switch 151 and the second switch 152 are N-channel transistors, the H-level of the scanning signal is a potential that can turn on the first switch 151 and the second switch 152, and the L-level of the scanning signal is a potential that can turn on the first switch 151 and the second switch 152.
Alternatively, the first switch 151 and the second switch 15
When the transistor 2 is a P-channel transistor, the H level of the scanning signal is a potential that can turn off the first switch 151 and the second switch 152, and the L level of the scanning signal is a potential that can turn off the first switch 151 and the second switch 152.
The potential is a potential that can turn on the first switch 151 and the second switch 152. The video signal is an analog voltage. However, the present invention is not limited to this, and the video signal may be a digital voltage. Alternatively,
The video signal may be a current, and may be analog or digital. The video signal has a potential lower than the H level of the scanning signal and higher than the L level of the scanning signal.

Regarding the operation of the pixel 150 in FIG.
The following describes two cases: when the switch 152 is on, and when the first switch 151 and the second switch 152 are off.

When the first switch 151 is on, the first wiring 158 is electrically connected to the first electrode (pixel electrode) of the first liquid crystal element 153 and the first electrode of the first capacitor 156. When the second switch 152 is on, the second wiring 159 is electrically connected to the first electrode (pixel electrode) of the second liquid crystal element 154 and the first electrode of the second capacitor 157. Therefore, a video signal is transmitted from the first wiring 158 to the first liquid crystal element 153.
and the first electrode of the first capacitor 156, and the first electrode (pixel electrode) of the second liquid crystal element 154 and the second capacitor 157 are input from the second wiring 159.
Therefore, the potential V ₁ of the signal input to the first liquid crystal element 153 is
_{The potential V 53} is approximately equal to the potential input from the first wiring 158, and the potential V ₁₅₄ of the signal input to the second liquid crystal element 154 is approximately equal to the potential input from the second wiring 159.
The potential V ₁₆₁ of the first electrode of the third capacitor element 161 is the same as that of the third liquid crystal element 105 in FIG.
The potential _V161 of the first electrode of the third capacitor 161 is approximately equal to half the sum of _V153 and _V154 when _C106 and _C107 are the same. Note that the potential of the first electrode of the third liquid crystal element ₁₅₅ is V155. If the potential of the common electrode is set to 0, the voltage applied to the third liquid crystal element 155 is _V155 . _V155 is a value obtained by dividing the voltage between the third capacitor 161 and the third liquid crystal element _155. In this way, by using a capacitor, different voltages can be further supplied to the liquid crystal element. In this way, the voltages applied to the liquid crystal elements can be made different, and the orientation states of the liquid crystal elements can be made different.

In this way, by supplying two signals with different potentials and using a capacitive element, the voltage can be divided inside the pixel to generate a third voltage. Then, by applying the third voltage to the third liquid crystal element 105, the liquid crystal can be easily controlled. Furthermore, the third voltage is a voltage between the voltage supplied to the first liquid crystal element 103 and the voltage supplied to the second liquid crystal element 104. Therefore, no matter what kind of gradation is displayed, an appropriate gradation can be displayed. Furthermore, no matter whether the polarity of the image signal is positive (when the image signal is higher than the common electrode) or negative (when the image signal is lower than the common electrode), an appropriate gradation can be displayed.

Furthermore, the third voltage can be generated to control the third liquid crystal element 155 while suppressing the increase in the number of scanning lines, signal lines, transistors, etc. This allows the aperture ratio to be increased and power consumption to be reduced. In addition, the layout of the pixels can be arranged with a margin, so that defects such as short circuits caused by dust generated in the manufacturing process can be reduced, and the yield is improved. As a result, the manufacturing cost can be reduced. In addition, since the third liquid crystal element 155 can be controlled without providing new signal lines, the number of connection points between the glass substrate and the external driving circuit does not increase. As a result, high reliability can be maintained.

When the first switch 151 is off, the first wiring 158 is electrically disconnected from the first electrode (pixel electrode) of the first liquid crystal element 153 and the first electrode of the first capacitor 156. When the second switch 152 is off, the second wiring 159 is electrically disconnected from the first electrode (pixel electrode) of the second liquid crystal element 154 and the first electrode of the second capacitor 157. Therefore, the first electrode of the first liquid crystal element 153 and the first capacitor 156 are electrically disconnected from each other.
The first electrode of the third liquid crystal element 155, the first electrode of the second liquid crystal element 154, and the first electrode of the second capacitor element 157 are in a floating state.
The third liquid crystal element 105 is connected to the first liquid crystal element 153 via a second capacitor 156 and a third capacitor 161. However, due to the law of conservation of charge, the charge stored in the third liquid crystal element 105 does not leak to the first liquid crystal element 153. The third liquid crystal element 105 is connected to the first liquid crystal element 153 via a second capacitor 157. However, due to the law of conservation of charge, the charge stored in the third liquid crystal element 155 does not leak to the second liquid crystal element 153.
There is no leakage to the electrode 54. Therefore, the first to third liquid crystal elements hold the potential of the signal that was input immediately before.

It is to be noted that the first liquid crystal element 153, the second liquid crystal element 154, and the third liquid crystal element 155 have transmittance according to a video signal.

That is, compared with Fig. 1, Fig. 2 corresponds to a case where the third liquid crystal element 105 in Fig. 1 is replaced with the third capacitance element 161 and the third liquid crystal element 155 in Fig. 2 connected in series. Therefore, the contents described in Fig. 1 can also be applied to Fig. 2. For example, as shown in Fig. 15, the third capacitance element 161 and the third liquid crystal element 155 connected in series may be divided into a plurality of elements. Alternatively, as shown in Fig. 12, the capacitance element may be omitted and only the liquid crystal element may be divided into a plurality of elements.

In FIG. 2, the portion of the third liquid crystal element 105 in FIG. 1 is a third capacitance element 161 and a third
13 shows a case where the first liquid crystal element 153 is replaced with a capacitor element and a liquid crystal element connected in series. In this case, as in FIG. 12, the first liquid crystal element 153 is replaced with a capacitor element and a liquid crystal element connected in series.
As shown in FIG.

2 is obtained by replacing the third liquid crystal element 105 in FIG. 1 with the third capacitance element 161 and the third liquid crystal element 155 in FIG. 2 connected in series, and therefore the same modifications as those in FIG. 1 are possible. That is, a storage capacitor may be added to a part of each liquid crystal element as shown in FIG. 7, or a storage capacitor may be added to all of the liquid crystal elements as shown in FIG. 16. Also, the number of scanning lines may be two and the signal line may be combined into one as shown in FIG. 8 or FIG. 18, or a storage capacitor may be added to all of the liquid crystal elements as shown in FIG. 17.
Alternatively, as shown in FIG. 19, both the scanning line and the signal line may be combined into one line.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

3 shows an example of a pixel circuit configuration different from others in the liquid crystal display device of the present invention. The pixel 200 includes a first switch 201, a second switch 202, a transistor 203, a first liquid crystal element 204, a second liquid crystal element 205, and a third liquid crystal element 206.
06 , a first capacitor 207 , and a second capacitor 208 .

The first wiring 209 is connected to a first electrode of the first liquid crystal element 204 and a first electrode of the first capacitor element 207 via a first switch 201.
The second wiring 210 is connected to a first electrode of the third liquid crystal element 206 and a first electrode of the second capacitor element 208 through the second switch 202.
A second electrode of the first capacitor 207 is connected to a second electrode of the second capacitor 208 and a first electrode of the third liquid crystal element 206 through a transistor 203. Gates of the first switch 201, the second switch 202, and the transistor 203 are connected to a third wiring 211. A second electrode of the first capacitor 207 is connected to a second electrode of the second capacitor 208 and a first electrode of the third liquid crystal element 206.

The transistor 203 operates as a switch having a higher on-resistance than the first switch 201 and the second switch 202. In other words, the transistor 203 can be treated as a switch having resistive elements connected in series. However, the present invention is not limited to this. The on-resistance of the transistor 203 may be lower than the on-resistance of the first switch 201 and the second switch 202.

3, the transistor 203 is an N-channel transistor, but is not limited to this, that is, the transistor 203 may be a P-channel transistor.

The second electrodes of the first liquid crystal element 204, the second liquid crystal element 205 and the third liquid crystal element 206 are connected to a common electrode.

The first wiring 209 and the second wiring 210 function as signal lines. Therefore, image signals are usually supplied to the first wiring 209 and the second wiring 210. However, this is not limited to this. A constant signal may be supplied regardless of the image. The third wiring 211 functions as a scanning line.

The first switch 201 and the second switch 202 are not particularly limited as long as they function as switches. For example, transistors can be used. Hereinafter, a case where transistors are used as the first switch 101 and the second switch 102 will be described. When transistors are used, the polarity of the transistors may be P-channel type or N-channel type.

FIG. 3B shows a case where an N-channel transistor is used as a switch.
2, gates of a first switch 201N and a second switch 202N are connected to a third wiring 110. A third wiring 211A functions as a scan line.

As in FIG. 1, in FIG. 2 as well, two scanning lines may be provided as shown in FIG.
It is also possible to use a P-channel transistor as the switch.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

A video signal is input to the first wiring 209 and the second wiring 210. A scanning signal is input to the third wiring 211. The scanning signal is an H-level or L-level digital voltage signal. When the first and second switches and the transistor 203 are N-channel type, the H-level of the scanning signal is a potential that can turn on the first to third transistors, and the L-level of the scanning signal is a potential that can turn off the first and second switches and the transistor 203. Alternatively, when the first and second switches and the transistor 203 are P-channel type, the H-level of the scanning signal is a potential that can turn off the first and second switches and the transistor 203, and the L-level of the scanning signal is a potential that can turn off the first and second switches and the transistor 203.
03 can be turned on. The video signal is an analog voltage. However, the present invention is not limited to this, and the video signal may be a digital voltage. Alternatively, the video signal may be a current. The current of the video signal may be either analog or digital. The video signal is at a potential lower than the H level of the scanning signal and higher than the L level of the scanning signal.

That is, in comparison with FIG. 1, FIG. 3 shows that the pixel electrode of the third liquid crystal element 206 in FIG.
It can be said that the transistor 203 connected to the wiring 210 of the first capacitor element 207 is added. In the case of FIG. 1, if some noise or leakage current enters the connection point between the first capacitor element 207 and the second capacitor element 208, electric charge accumulates there. As a result, the voltage applied to the liquid crystal element is affected, and there is a possibility that image quality will deteriorate. However, by adding the transistor 203 as shown in FIG. 3, it is possible to extract the accumulated electric charge. As a result, image quality defects such as burn-in can be reduced.

As described above, it is desirable that the on-resistance of the transistor 203 is higher than the on-resistance of the first switch 201 or the second switch 202. A high on-resistance of a transistor means that the ratio (W/L) of the channel width W to the channel length L is small.
In this way, by increasing the on-resistance of the transistor, the potential at the point where the first capacitance element 207 and the second capacitance element 208 are connected is determined by the balance of leakage currents of the capacitance elements and the storage capacitances, etc. However, this is not limited to this, and the first to third transistors may be formed to have approximately the same size, and a resistance element may be connected in series with the third transistor 203.

Therefore, the contents described in Figures 1 and 2 can also be applied to Figure 3. For example, Figure 4 shows a case where Figure 2 is applied to Figure 3.

In addition, in FIG. 3 and FIG. 4, the first switch 201N (or the first switch 251
N), a second switch 202N (or a second switch 252N), and a transistor 203
The transistor 253 is controlled by the third wiring 211 (or the third wiring 262), but is not limited to this. These may be connected to different wirings and controlled separately. Alternatively, a part of each of the transistors may be connected to a different wiring.

3, the transistor 203 is connected to the second wiring 210, but may be connected to the first wiring 209. The same applies to the case where the third transistor 203 is connected to the first wiring 209. As in FIG. 3, the transistor 253 is connected to the second wiring 261 in FIG. 4, but may be connected to the first wiring 260.

Alternatively, a separate wiring may be provided to connect the transistor. This case is shown in Fig. 5. In Fig. 5B, two scan lines are arranged, and the scan line that controls the first switch 301N and the second switch 302N and the scan line that controls the transistor 303 are different wirings, but this is not limited to this. The first switch 301N, the second switch 302N, and the transistor 303 may be connected to the same scan line. Therefore, the contents described in other figures such as Fig. 1 can also be applied to Fig. 5. For example, a case in which Fig. 2 is applied to Fig. 5 is shown in Fig. 6.

5, the transistor 303 is preferably turned on when the first switch 301 or the second switch 302 is turned off, but is not limited to this. The transistor 303 may be turned on when the first switch 301 or the second switch 302 is turned on, or during a part of the period (preferably the first half) when the first switch 301 or the second switch 302 is turned on.

Note that the potential of the fifth wiring 313 is preferably set to be substantially equal to the potential of the common electrode, but is not limited to this. It is also possible for the potential of the fifth wiring 313 to be substantially equal to the potential of the first wiring 309 or the second wiring 310.

The fifth wiring 313 can be used in common with other wirings. For example, a capacitance line,
The wiring can be shared with a scanning line, etc. The shared wiring may be wiring for another pixel. This can improve the aperture ratio. The contents described in other figures such as FIG. 1 can also be applied to FIG. 5. That is, at least one of the transistors may be a P-channel type, and the liquid crystal element may be divided into multiple elements.

In FIG. 6, the transistor 353 is connected to the third capacitor 359.
The present invention is not limited to this. A transistor 353 may be connected between a contact point between the third capacitor element 359 and the third liquid crystal element 356 and a fifth wiring 364. Note that the contents described with reference to other diagrams such as FIG. 1 can also be applied to FIG. 6.

The transmittance of the first to third liquid crystal elements described above corresponds to the video signal.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

Although the above description has been given of the case where two capacitive elements are connected between the signal lines via a switch, this is not limiting. It is possible to arrange many more capacitive elements. By adding capacitive elements, the voltages applied to the liquid crystal elements can be made to be more different. Then, by applying each of these voltages to each liquid crystal element, it is possible to arrange many liquid crystal elements to which different voltages are applied. As a result, the viewing angle can be widened.

Therefore, an example in which a capacitance element and a liquid crystal element are further added to the arrangement shown in FIG.
20 shows an example in which a capacitor element and a liquid crystal element are further added to FIG. 3. A liquid crystal element may be further added. The first liquid crystal element 503 is a third
9 and 20. The liquid crystal element 505 may be connected to the liquid crystal element 505 in the same manner. Similarly, a capacitor element and a liquid crystal element can be added to the circuits shown in the other figures. The contents described in the explanation of the other figures can also be applied to FIG. 9 and FIG. 20.

In FIG. 9, a pixel 500 includes a first switch 501, a second switch 502, a first liquid crystal element 503, a second liquid crystal element 504, a third liquid crystal element 505, a fourth liquid crystal element 506, a first capacitor element 507, a second capacitor element 508, and a third capacitor element 509.
9 , a first wiring 510 , a second wiring 511 , and a third wiring 512 .

The first wiring 510 is connected to the first electrode of the first liquid crystal element 503 and the first electrode of the first capacitor element 507 via the first switch 501. The second wiring 511 is connected to the first electrode of the second liquid crystal element 504 and the first electrode of the third capacitor element 509 via the second switch 501.
The second electrode of the first capacitor 507 is connected to the second capacitor 508 via a terminal 2.
A second electrode of the second capacitor 508 is connected to a first electrode of the third capacitor 509 and a first electrode of the fourth liquid crystal element 506. A second electrode of the second capacitor 508 is connected to a second electrode of the third capacitor 509 and a first electrode of the fourth liquid crystal element 506.

Second electrodes of the first liquid crystal element 503, the second liquid crystal element 504, the third liquid crystal element 505 and the fourth liquid crystal element 506 are connected to a common electrode.

The first wiring 510 and the second wiring 511 function as signal lines.
An image signal is usually supplied to the first wiring 510 and the second wiring 511. However, this is not limiting. A constant signal may be supplied regardless of the image. The third wiring 512 functions as a scan line.

There is no particular limitation on the first switch 501 and the second switch 502 as long as they function as switches. For example, when a transistor is used, the polarity may be either a P-channel type or an N-channel type.

FIG. 9B shows a case where an N-channel transistor is used as a switch.
), the gates of the first switch 501N and the second switch 502N are connected to a third wiring 512. The third wiring 512 functions as a scan line.

9, similarly to FIG. 1, two scanning lines may be provided as shown in FIG.
It is also possible to use a P-channel transistor as the switch.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

Furthermore, the liquid crystal element may be divided into multiple parts as shown in Figure 11, etc.

Note that the first liquid crystal element 503, the second liquid crystal element 504, the third liquid crystal element 505, and the fourth liquid crystal element 506 are
The liquid crystal element 506 has a transmittance according to a video signal.

As described above, it is possible to provide four liquid crystal elements per pixel, or to further increase the number of liquid crystal elements per pixel. By increasing the number of liquid crystal elements per pixel, it is possible to provide various alignment states, and it is possible to provide a liquid crystal display device having a wider viewing angle.

9 and 20, the liquid crystal element is added by adding a capacitor element. However, this is not limited to this. By increasing the number of transistors, signal lines, etc.,
The number of liquid crystal elements disposed in one pixel can be increased. Thus, as an example, FIG. 10 shows a case where a liquid crystal element is added and disposed by increasing the number of transistors and signal lines in the circuit of FIG. 1. However, the present invention is not limited to this configuration. In FIG. 10, a signal line is added without adding a scanning line, but a scanning line can be added without adding a signal line. FIG. 21 shows a case where a capacitor element 584 is added without adding a signal line and disposed between the signal line and the fourth liquid crystal element 557, thereby dividing a potential supplied from the signal line. FIG. 22 shows a case where a capacitor element is added without adding a signal line, a capacitor element 572 is added between the signal line and the first liquid crystal element 554, and disposed between the signal line and the first liquid crystal element 554, thereby dividing a potential supplied from the signal line. By using the configurations shown in FIG. 21 and FIG. 22, different voltages can be applied to four liquid crystal elements without adding a signal line.

Although the fourth liquid crystal element 557 is connected to the first wiring 560 in FIG. 21 and FIG. 22, the fourth liquid crystal element 557 may be connected to the second wiring 561 .

It should be noted that, similarly to the case of Fig. 1, liquid crystal elements can be added and arranged in the circuits shown in the other figures. The contents described in the explanation of the other figures can also be applied to Fig. 10. In other words, the transistors may be of the P-channel type, and the liquid crystal element may be divided into a plurality of elements.

In FIG. 10, a pixel 550 includes a first switch 551, a second switch 552, and
A third switch 553, a first liquid crystal element 554, a second liquid crystal element 555, a third liquid crystal element 556, a fourth liquid crystal element 557, a first capacitor element 558, and a second capacitor element 559.
59 and.

The first wiring 560 is connected to a first electrode of the first liquid crystal element 554 and a first electrode of the first capacitor 558 via a first switch 551. The second wiring 561 is connected to a first electrode of the second liquid crystal element 555 and a first electrode of the second capacitor 559. The third wiring 562 is connected to a first electrode of the fourth liquid crystal element 557 via a third switch 553. The second electrode of the first capacitor 558 is connected to a second electrode of the second capacitor 559 and one of the first electrodes of the third liquid crystal element 556.

FIG. 10B shows a case where an N-channel transistor is used as a switch.
In (B), the gates of the first switch 551N and the second switch 552N are connected to a fourth wiring 563. The fourth wiring 563 functions as a scan line.

10, similarly to FIG. 1, two scanning lines may be provided as shown in FIG.
It is also possible to use a P-channel transistor as the switch.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

Furthermore, the liquid crystal element may be divided into several parts as shown in FIG. 11, etc.

Second electrodes of the first liquid crystal element 503, the second liquid crystal element 504, the third liquid crystal element 505 and the fourth liquid crystal element 506 are connected to a common electrode.

The first wiring 560, the second wiring 561, and the third wiring 562 function as signal lines.
An image signal is supplied. However, this is not limiting. A constant signal may be supplied regardless of the image. The fourth wiring 563 functions as a scan line.

Note that a capacitor may be provided between the liquid crystal element and the wiring functioning as a signal line.
1, the voltage applied to the liquid crystal element can be made different by providing a capacitor 566. Therefore, the first wiring 560 and the third wiring 562 in FIG.

Note that the position where the capacitor element is added is not limited to between the fourth liquid crystal element and the signal line, and a capacitor element (for example, a capacitor element 565) may be provided between another liquid crystal element and the signal line as shown in Fig. 22. In this case, a plurality of signal lines can be integrated into one.

As described above, it is possible to provide four liquid crystal elements per pixel, or to further increase the number of liquid crystal elements per pixel. By increasing the number of liquid crystal elements per pixel, it is possible to provide various alignment states, and it is possible to provide a liquid crystal display device having a wider viewing angle.

An example of a top view of a pixel of a liquid crystal display device to which the present invention is applied is shown in Fig. 32. Also, Fig. 33 shows a circuit diagram of Fig. 32. Note that the same reference numerals are used for corresponding parts in Fig. 32 and Fig. 33.

The pixel 1000 shown in FIG. 32 includes a first conductive layer (
A first insulating film (not shown) is provided on the third wiring 1013, a semiconductor film is provided on the first insulating film, and a second conductive layer (the first wiring 1013 is shown by a hatched pattern) is provided on the semiconductor film.
A first conductive layer (indicated by a hatch pattern of 011) is provided on the first insulating film (not shown), and a third conductive layer (indicated by a hatch pattern of the first liquid crystal element 1003) is provided on the second insulating film.

In FIG. 33, a pixel 1000 includes a first switch 1001 and a second switch 100
2, a first liquid crystal element 1003, a second liquid crystal element 1004, and a third liquid crystal element 1005.
a fourth liquid crystal element 1006, a first capacitor 1007, a second capacitor 1008, a third capacitor 1009, a fourth capacitor 1010, and a fifth capacitor 1016,
and a sixth capacitor 1017.

The first wiring 1011 is connected to the fourth liquid crystal element 1006, a first electrode of the first capacitor 1007, and a first electrode of the second capacitor 1008 through the first transistor 1001.
The second electrode of the second capacitor 1008 is connected to the first electrode of the third capacitor 1009 through the second transistor 1002.
the second electrode of the fifth capacitor 1016, the first electrode of the second liquid crystal element 1004,
The first electrode of the first capacitor 1007 and the second electrode of the sixth capacitor 1017 are connected to a fifth wiring 1015. The second electrode of the fifth capacitor 1016 and the second electrode of the fourth capacitor 1010 are connected to a fourth wiring 1014.

In addition, Fig. 33 shows a configuration in which a storage capacitor is provided for each of all the liquid crystal elements in Fig. 11(B). In other words, it can be said to be a combination of Fig. 11 and Fig. 16. Therefore, Fig. 33 can be applied with the same configuration as Fig. 1. That is, the wiring functioning as the capacitance line may be shared with the common electrode as shown in Fig. 50, and the switch can be replaced with a transistor, and either an N-channel type or a P-channel type may be used for the transistor.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

The first wiring 1011 and the second wiring 1012 function as signal lines.
An image signal is usually supplied to the first wiring 1011 and the second wiring 1012. However, this is not limited to this. A constant signal may be supplied regardless of the image.
The fourth wiring 1014 and the fifth wiring 1015 function as capacitance lines.

By providing a pixel as shown in the top view of FIG. 32, each liquid crystal element can have various alignment states, and a liquid crystal display device having a wider viewing angle can be provided.

In this embodiment, the case where all the transistors provided in one pixel have the same conductivity type has been described, but the present invention is not limited to this. In other words, the transistors provided in one pixel may have different conductivity types.

Furthermore, the type of transistor in this embodiment is not particularly limited, and various types can be used. For this reason, thin film transistors (TFTs) using a crystalline semiconductor film, thin film transistors using a non-single crystal semiconductor film such as amorphous silicon or polycrystalline silicon, transistors formed using a semiconductor substrate or SOI substrate, MOS type transistors, junction type transistors, bipolar transistors, transistors using compound semiconductors such as ZnO or a-InGaZnO, transistors using organic semiconductors or carbon nanotubes,
Other transistors can be used. However, it is preferable to use a transistor with a low off-current. Examples of a transistor with a low off-current include a thin film transistor provided with an LDD region and a thin film transistor having a multi-gate structure.
Both N-channel and P-channel types may be used to form a CMOS switch.

In this embodiment, various drawings have been used to describe the present invention. However, a part or all of the contents described in each drawing may be applied to, combined with, or used in conjunction with a part or all of the contents described in another drawing.
Furthermore, in the figures described above, by combining each part with another part, many more configurations can be considered.
The description of this embodiment does not preclude this.

Similarly, a part or all of the contents described in each figure of this embodiment can be freely applied to, combined with, or replaced with a part or all of the contents described in the figures of another embodiment. Furthermore, by combining each part of the figures of this embodiment with parts of another embodiment, even more figures can be configured, and the description of this embodiment does not prevent this.

This embodiment shows an example of a case where a part or all of the contents described in the other embodiments are embodied, slightly modified, partially changed, improved, described in detail, applied, or related. Therefore, the contents described in the other embodiments can be freely applied to this embodiment, combined, or replaced.

(Embodiment 2)
In the first embodiment, a new voltage is generated by dividing a voltage using a capacitive element and supplied to the liquid crystal element, but the element for generating the new voltage is not limited to a capacitive element.
Voltage dividing elements, current to voltage converting elements, non-linear elements, elements with resistance components,
Various elements such as elements having capacitance components, inductors, diodes, transistors, resistors, and switches can be used. Furthermore, by connecting and combining these in series or parallel, a desired circuit can be realized. Such elements are called voltage dividing elements.

23 shows a generalized case in which the capacitance element in FIG. 1 is used as a voltage dividing element. Therefore, the contents described in the first embodiment can also be applied to FIG.

23A shows an example of the configuration of a pixel circuit included in a liquid crystal display device of the present invention. A pixel 600 includes a first switch 601, a second switch 602, and a first liquid crystal element 6
03, a second liquid crystal element 604, a third liquid crystal element 605, and a first voltage dividing element 606,
and a second voltage dividing element 607.

The first wiring 608 is connected to a first electrode of the first liquid crystal element 603 and one end of the first voltage dividing element 606 via a first switch 601. The second wiring 609 is connected to a first electrode of the second liquid crystal element 604 and one end of the second voltage dividing element 607 via a second switch. The first voltage dividing element 606 and the second voltage dividing element 607 are connected in series, and the first electrode of the third liquid crystal element 605 is connected between the first voltage dividing element 606 and the second voltage dividing element 607.

The second electrodes of the first liquid crystal element 603, the second liquid crystal element 604, and the third liquid crystal element 605 are connected to a common electrode.

FIG. 23B shows a case where an N-channel transistor is used as a switch.
In (B), the gates of the first switch 601N and the second switch 602N are connected to a third wiring 610. The third wiring 760 functions as a scan line.

26, similarly to FIG. 1, two scanning lines may be provided as shown in FIG. 49, and P-channel transistors may be used as switches.
As shown in the above, the liquid crystal element may be further divided into a plurality of elements.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

The first wiring 608 and the second wiring 609 function as signal lines. Therefore, image signals are usually supplied to the first wiring 608 and the second wiring 609. However, this is not limited to this. A constant signal may be supplied regardless of the image. The third wiring 610 functions as a scanning line.

The first liquid crystal element 603, the second liquid crystal element 604, and the third liquid crystal element 605 have transmittance according to a video signal.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

Note that not only capacitive elements but also various other elements can be used as the first voltage dividing element 606 and the second voltage dividing element 607. For example, an element that divides a voltage, an element that converts a current into a voltage, a nonlinear element, an element having a resistive component, an element having a capacitive component, an inductor, a diode, a transistor, a resistive element, a switch, etc. can be used as the voltage dividing element. Fig. 30 illustrates an example of the voltage dividing element.

First, as shown in FIGS. 30(J) and (K), an N-channel transistor and a P-channel transistor can be used.

FIG. 30A shows a diode-connected N-channel transistor.
30(C) is the same as FIG. 30(A) except that the connection direction is reversed.
In this example, the elements shown in Fig. 30A and Fig. 30B are connected in parallel. In Fig. 30D and Fig. 30E, the N-channel transistors in Fig. 30A and Fig. 30B are replaced with P-channel transistors. The P-channel transistors may be connected in parallel as in Fig. 30C. Alternatively, as shown in Fig. 30F, a P-channel transistor and an N-channel transistor may be connected in parallel.

30(G) and (L) show voltage dividing elements in which a resistive element and a capacitive element are connected in series or in parallel.

In FIGS. 30H and 30I, a resistor element and a P-channel transistor or an N-channel transistor are connected in series.

Note that there is no particular limitation on the wiring to which the gates of the transistors shown in Figures 30H, 30I, 30J, and 30K are connected. The wiring may be a scanning line, a capacitance line, or a signal line.
It may be connected to a scanning line of a row adjacent to the pixel in question. By controlling the potential of the gate, the resistance value of the voltage dividing element can be controlled.

30(M) and (N) show diodes. There are various types of diodes, but the diodes that can be used as voltage dividing elements are not particularly limited. For example, PN type, PI type,
It is possible to use diodes of N-type, Schottky type, MIM type, MIS type, etc. Furthermore, as shown in Fig. 30(O), two diodes may be connected in parallel in the opposite directions.

Furthermore, an inductor element as shown in Fig. 30(P) may be used, or a resistive element as shown in Fig. 30(Q) may be used. As the resistive element, one having a variable resistance value as shown in Fig. 30(R) may be used.

Therefore, in the configuration described in the first embodiment, a new circuit can be configured by replacing the capacitive element with the voltage dividing element shown in Fig. 30. Therefore, the contents described in the first embodiment can be applied to the circuit shown in Fig. 23 and configured by replacing the capacitive element with a voltage dividing element.

36 to 48 show circuit diagrams in which the voltage dividing element 606 and the voltage dividing element 607 shown in FIG. 23 are replaced with various elements shown in FIG. 30. Therefore, the same configuration as that of FIG. 1 can be applied to FIG. 36 to FIG. 48. That is, as shown in FIG. 7, the first electrodes of some or all of the liquid crystal elements may be connected to a capacitance line. The capacitance line may be shared with a common electrode as shown in FIG. 50. The switches can be replaced with transistors, and the transistors may be of N-channel type or P-channel type. When transistors are used, the gates of the transistors may be connected to the same scanning line or different scanning lines. Also, as shown in FIG. 11, the liquid crystal element may be divided into a plurality of elements. There may be a plurality of signal lines, or they may be combined into one as shown in FIG. 8. Furthermore, the liquid crystal element shown in FIG. 2 and FIG. 1 ...
As shown in FIG. 2, a voltage dividing element may be disposed at an appropriate position.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

The resistance value of the voltage dividing element does not have to be constant, and may be set to vary depending on time or pixel. In order to change the resistance value, the voltage dividing element may have a transistor. When a transistor is used, the potential of the gate of the transistor may be changed depending on time or pixel.

When voltage dividing elements are connected between liquid crystal elements, charge may leak between each liquid crystal element when the connection between the signal line and the liquid crystal element is turned off. In order to prevent charge leakage, the voltage dividing element and a switch are connected in series and connected between each liquid crystal element. An example of this case is shown in Figure 24. Note that the connection between the voltage dividing element and the switch may be reversed.

Although one voltage dividing element and one switch are disposed between the liquid crystal elements, the present invention is not limited to this. A plurality of voltage dividing elements and switches may be disposed between the liquid crystal elements. The contents described in the first embodiment and FIG. 23 can also be applied to FIG. 24.

The pixel 650 includes a first switch 651, a second switch 652, and a first liquid crystal element 6
53, a second liquid crystal element 654, a third liquid crystal element 655, and a first voltage dividing element 656,
The circuit includes a second voltage dividing element 657 , a third switch 658 , and a fourth switch 659 .

The first wiring 660 is connected to a first electrode of the first liquid crystal element 653 and one end of the third switch 658 via the first switch 651. The second wiring 661 is connected to a first electrode of the second liquid crystal element 654 and one end of the fourth switch 659. The third switch 658 and the fourth switch 659 are connected in series, and a first voltage dividing element 656 and a second voltage dividing element 657 connected in series are provided between the third switch 658 and the fourth switch 659. The first electrode of the third liquid crystal element 655 is connected to the first voltage dividing element 656 and the second voltage dividing element 657.
57.

The second electrodes of the first liquid crystal element 653, the second liquid crystal element 654, and the third liquid crystal element 655 are connected to a common electrode.

The first wiring 660 and the second wiring 661 function as signal lines. Therefore, image signals are usually supplied to the first wiring 660 and the second wiring 661. However, this is not limited to this. A constant signal may be supplied regardless of the image. The third wiring 662 functions as a scanning line.

The first switch 651 and the second switch 652 are not particularly limited as long as they function as switches. For example, transistors can be used. Hereinafter, when transistors are used as the first switch 651 and the second switch 652, the polarity of the transistors may be P-channel type or N-channel type.

The third switch 658 and the fourth switch 659 are not particularly limited as long as they function as switches. For example, transistors can be used.
The polarity of the transistors used for the eighth and fourth switches 659 may be P-channel or N-channel.
It may be of a channel type.

FIG. 24B shows a case where an N-channel transistor is used as a switch.
In (B), the gates of the first switch 651N and the second switch 652N are connected to a third wiring 662. The third wiring 662 functions as a scan line.

In addition, in FIG. 24, similarly to FIG. 1, etc., two scanning lines may be provided as shown in FIG. 49, and P-channel transistors may be used as switches.
As shown in the above, the liquid crystal element may be further divided into a plurality of elements.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

It is to be noted that the first liquid crystal element 653, the second liquid crystal element 654, and the third liquid crystal element 655 have transmittance according to a video signal.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

23 and 24 show a specific example in which the voltage dividing element in FIG. 30 is applied. First, the case in which FIG. 30(J) is used will be described with reference to FIG. 25. The gate is connected to a scanning line. FIGS. 23 and 24 correspond to a case in which the first capacitance element 106 and the second capacitance element 107 in FIG. 1 are replaced with transistors. Therefore, the first embodiment and FIG. 2
The contents described with reference to FIG. 3 and FIG. 24 can also be applied to FIG.

The pixel 700 includes a first switch 701, a second switch 702, and a first liquid crystal element 703.
03, a second liquid crystal element 704, a third liquid crystal element 705, and a first transistor 706.
and a second transistor 707 .

The first wiring 708 is connected to the first electrode of the first liquid crystal element 703 and the first transistor 706
A second wiring 709 is connected to a first electrode of a second liquid crystal element 704 and one of a source or a drain of a second transistor 707 through a second switch 702. The other of the source or the drain of the first transistor 706 and the other of the source or the drain of the second transistor 707 are connected to a first electrode of a third liquid crystal element 705. The first and second transistors are connected to a third wiring 710.

The second electrodes of the first liquid crystal element 703, the second liquid crystal element 704, and the third liquid crystal element 705 are connected to a common electrode.

The first wiring 708 and the second wiring 709 function as signal lines. Therefore, image signals are usually supplied to the first wiring 708 and the second wiring 709. However, this is not limiting. A constant signal may be supplied regardless of the image. The third wiring 710 functions as a scanning line.

The first switch 701 and the second switch 702 are not particularly limited as long as they function as switches. For example, transistors can be used. Hereinafter, a case where transistors are used as the first switch 701 and the second switch 702 will be described. When transistors are used, the polarity thereof may be a P-channel type or an N-channel type.

FIG. 25B shows a case where an N-channel transistor is used as a switch.
In (B), the gates of the first switch 701N and the second switch 702N are connected to a third wiring 710. The third wiring 710 functions as a scan line.

In addition, in FIG. 25, similarly to FIG. 1, etc., two scanning lines may be provided as shown in FIG. 49, and P-channel transistors may be used as switches.
As shown in the above, the liquid crystal element may be further divided into a plurality of elements.

The first transistor 706 and the second transistor 707 are only required to function as a voltage dividing element, and the polarity of the first transistor 706 and the second transistor 707 may be either a P-channel type or an N-channel type.

Next, the operation of the pixel 700 will be described. First, the pixel 700 is selected by the third wiring 710.
The first switch 701 and the second switch 702 are turned on. Then, the first wiring 7
A video signal is supplied from the first wiring 708 and the second wiring 709. At the same time as the first and second switches, the first transistor 706 and the second transistor 707 are also turned on. Therefore, the first wiring 708 and the second wiring 709 are connected via a transistor. Since the transistor has a resistance component (on-resistance), the voltage is divided by each transistor. At this time, if the on-resistance of the first transistor 706 and the second transistor 707 is high, most of the voltage is applied to these transistors.

Therefore, a potential substantially equal to the potential of the first wiring 708 is applied to the pixel electrode of the first liquid crystal element 703. More precisely, the potential of the first wiring 708 is applied to the first switch 701.
A potential equivalent to the voltage drop caused by the second switch 702 is applied to the pixel electrode of the first liquid crystal element 703. Similarly, a potential approximately equal to the potential of the second wiring 709 is applied to the pixel electrode of the second liquid crystal element 704. More precisely, a potential equivalent to the voltage drop caused by the second switch 702 from the potential of the second wiring 709 is applied to the pixel electrode of the second liquid crystal element 704.

The potential of the pixel electrode of the first liquid crystal element 703 and the potential of the pixel electrode of the second liquid crystal element 704 are divided by the first transistor 706 and the second transistor 707 and supplied to the pixel electrode of the third liquid crystal element 705.
When the on-resistances of the second transistor 707 and the third liquid crystal element 70 are approximately equal to each other,
The potential of the pixel electrode of the first liquid crystal element 703 and the potential of the pixel electrode of the second liquid crystal element 705 are
The potential of the pixel electrode 4 is intermediate between these.

Note that when the on-resistance of the first switch 701, the second switch 702, the first transistor 706, the second transistor 707, and the like is small, a large current flows.
Therefore, it is desirable that the first transistor 706 and the second transistor 707, which are transistors for voltage division, have high on-resistance.
6 or the second transistor 707, the first switch 701 or the second switch 70
It is desirable that the ratio (W/L) of the channel width W to the channel length L is smaller in the second transistor 702. For example, the first transistor 706 or the second transistor 707 may have a multi-gate structure to increase the channel length L.

It is preferable that the first transistor 706 and the second transistor 707 have approximately equal on-resistance. When the on-resistances are approximately equal, the divided voltage becomes an intermediate potential. If there is a difference in the on-resistance, the potential will be biased toward one of the two.
This is because the liquid crystal element cannot be controlled. For example, it is preferable that the ratio (W/L) of the channel width W to the channel length L of the first transistor 706 and the second transistor 707 be approximately equal to each other. However, this is not limiting.

When the third wiring 710 is in a non-selected state, the first switch 701 and the second switch 70
2. The first transistor 706 and the second transistor 707 are turned off. Then,
The voltage supplied to each liquid crystal element is maintained. By operating in this manner, the voltage applied to each liquid crystal element can be made different. As a result, the viewing angle can be widened. However, the driving method is not limited to this. The timing of turning on and off each transistor, the potential of the signal line, etc. can be controlled by various methods.

In addition, since the first transistor 706 and the second transistor 707 are also turned off, no charge leaks between the liquid crystal elements. Therefore, it can be said that the first transistor 706 and the second transistor 707 realize the voltage dividing element and the switch in FIG. 24 by a single element.

It is to be noted that the first liquid crystal element 703, the second liquid crystal element 704, and the third liquid crystal element 705 have transmittances according to a video signal.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

Note that the first transistor 706 and the second transistor 707 are not limited to the configuration shown in the figure. For example, one or both of the first transistor 706 and the second transistor 707 may have a multi-gate structure. The multi-gate structure makes it easier to adjust the resistance values of the first transistor 706 and the second transistor 707 than in the case of a single-gate structure. Furthermore, the on-resistance of the first transistor 706 and the second transistor 707 can be made larger than in the case of a single-gate structure.

Note that the resistance values of the first transistor 706 and the second transistor 707 do not need to be constant, and may be set to vary depending on time or pixels. In order to change the resistance value, the first transistor 706 and the second transistor 707 function as voltage dividing elements.
7, the potential of the gate may be changed depending on time or on the pixel.

Although the storage capacitance is not shown in FIGS. 23 to 25, as described in FIG. 1, etc.,
As an example, a case in which a storage capacitor is provided for each liquid crystal element in FIG.

In FIG. 26, a pixel 750 includes a first switch 751, a second switch 752, and
The liquid crystal display device includes a first liquid crystal element 753 , a second liquid crystal element 754 , a third liquid crystal element 755 , a first transistor 756 , a second transistor 757 , a first capacitor 762 , a second capacitor 763 , and a third capacitor 764 .

The first wiring 758 is connected to the first electrode of the first liquid crystal element 753, one of the source and drain of the first transistor 756, and the first electrode of the third capacitor element 764.
The second wiring 759 is connected to a first electrode of the second liquid crystal element 754, one of the source and the drain of the second transistor 757, and a first electrode of the first capacitor element 762.
The other of the source and the drain of the transistor 757 is connected to a first electrode of the third liquid crystal element 755 and a first electrode of the second capacitor 763. The first and second switches and the first and second transistors are connected to a third wiring 760.
Second electrodes of the second capacitor 763 and the third capacitor 764 are connected to a fourth wiring 761 .

Second electrodes of the first liquid crystal element 753, the second liquid crystal element 754, and the third liquid crystal element 755 are connected to a common electrode.

The first wiring 758 and the second wiring 759 function as signal lines.
The fourth wiring 761 functions as a capacitance line.

The first switch 751 and the second switch 752 are not particularly limited as long as they function as switches. For example, transistors can be used.
When a transistor is used as the second switch 752, the polarity thereof may be either a P-channel type or an N-channel type.

FIG. 26B shows a case where an N-channel transistor is used as a switch.
In (B), the gates of the first switch 751N and the second switch 752N are connected to a third wiring 760. The third wiring 760 functions as a scan line.

In addition, in FIG. 26, similarly to FIG. 1, etc., two scanning lines may be provided as shown in FIG. 49, and P-channel transistors may be used as switches.
As shown in the above, the liquid crystal element may be further divided into a plurality of elements.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

The first transistor 756 and the second transistor 757 are only required to function as a voltage dividing element, and the polarity of the first transistor 756 and the second transistor 757 may be either a P-channel type or an N-channel type.

Note that the first liquid crystal element 753, the second liquid crystal element 754, and the third liquid crystal element 755 have transmittance according to a video signal.

Note that the resistance values of the first transistor 756 and the second transistor 757 do not need to be constant, and may be set to vary depending on time or pixel. In order to change the resistance value, the potential of the gate of the first transistor 756 and the second transistor 757 functioning as a resistor may be changed depending on time or pixel.

As described above, each liquid crystal element can be made to have a different alignment state, and the viewing angle can be made wider.

In FIG. 25 and FIG. 26, the gates of the first and second transistors are connected to the scanning line, but this is not limiting. A separate wiring may be arranged and connected to the wiring. Alternatively, a plurality of separate wirings may be arranged and the gates of the first and second transistors may be connected to the separate wirings. FIG. 27B shows a case where the gates of the first and second transistors are connected to the fourth wiring in FIG. 27A. In this way, the potentials of the gates of the first and second transistors can be controlled independently from the first and second switches, and the on-resistances of the first and second transistors can be easily controlled. For example, when a video signal of a negative polarity (the video signal is lower than the potential of the common electrode) is input, the gate-source voltages of the first and second transistors become very large. Therefore, the on-resistances of the first and second transistors decrease, and a large current flows, which may result in high power consumption. Therefore, when the first and second transistors are turned on to divide the voltage, the gate potentials of the first and second transistors are set lower when a negative video signal is input than when a positive video signal (the video signal has a higher potential than the common electrode) is input, thereby preventing a large current from flowing.

The pixel 800 includes a first switch 801, a second switch 802, a first transistor 803, a second transistor 804, a first liquid crystal element 805, and a second liquid crystal element 806.
806 and a third liquid crystal element 807.

The first wiring 808 is connected to the first electrode of the first liquid crystal element 805 and the first transistor 80
The second wiring 809 is connected to a first electrode of the second liquid crystal element 806 and one of a source or a drain of the second transistor 804 through a first switch 802.
The other of the source or the drain of the first switch 801 and the other of the source or the drain of the second transistor 804 are connected to a first electrode of a third liquid crystal element 807.
The gate of the switch 802 is connected to the third wiring 810.
The gates of the second transistor 803 and the second transistor 804 are connected to a fourth wiring 811 .

The second electrodes of the first liquid crystal element 805, the second liquid crystal element 806, and the third liquid crystal element 807 are connected to a common electrode.

The first wiring 808 and the second wiring 809 function as signal lines. Therefore, an image signal is usually supplied to the first wiring 808 and the second wiring 809. However, this is not limited to this. Regardless of the image, a constant signal may be supplied. The third wiring 810 and the fourth wiring 811 function as scanning lines.

The first switch 801 and the second switch 802 are not particularly limited as long as they function as switches. For example, transistors can be used.
When a transistor is used as the second switch 802, the polarity thereof may be either a P-channel type or an N-channel type.

FIG. 27B shows a case where an N-channel transistor is used as a switch.
In (B), the gates of the first switch 801N and the second switch 802N are connected to a third wiring 810. The third wiring 760 functions as a scan line.

27, similarly to FIG. 1, two scanning lines may be provided as shown in FIG. 49, and P-channel transistors may be used as switches.
As shown in the above, the liquid crystal element may be further divided into a plurality of elements.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

The first transistor 803 and the second transistor 804 are only required to function as voltage dividing elements, and the polarity of the first transistor 803 and the second transistor 804 may be either P-channel type or N-channel type.

When the first transistor 803 and the second transistor 804 are turned on to function as a voltage dividing element,
It is desirable to operate the first transistor 803 and the second transistor 804 in a linear region so that the on-resistance of the first transistor 803 and the second transistor 804 has an appropriate value.

Note that it is preferable that the timing at which the first switch 801 and the second switch 802 are turned on and off is approximately the same as the timing at which the first transistor 803 and the second transistor 804 are turned on and off. However, this is not limiting.
When the first and second switches 802 are turned on, after a short delay, the first transistor 80
The third and second transistors 804 may be turned on. This can shorten the period during which the first wiring 808 and the second wiring 809 are connected to each other. This makes it easier to input electric charges to the first liquid crystal element 805 and the second liquid crystal element 806.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

Next, an example in which the contents described in the first embodiment are applied to FIG. 25 is shown. An example of a circuit configured by replacing the capacitance element with the voltage dividing element shown in FIG. 30 is shown. FIG. 28 shows a case in which the first capacitance element and the second capacitance element in FIG. 2 are replaced with those in FIG. 30(J). In this case, the gate of the transistor of the voltage dividing element is connected to the scanning line. However, this is not limited to this. Therefore, the contents described in the first embodiment can also be applied to FIG. 28.

The pixel 850 includes a first switch 851, a second switch 852, and a first liquid crystal element 8
53, a second liquid crystal element 854, a third liquid crystal element 855, and a first transistor 856
857 , and a capacitor 861 .

The first wiring 858 is connected to the first electrode of the first liquid crystal element 853 and the first transistor 85
A first wiring 859 is connected to one of a source or a drain of a second transistor 856 through a first switch 851. A second wiring 859 is connected to a first electrode of a second liquid crystal element 854 and one of a source or a drain of a second transistor 857. The other of the source or the drain of the first transistor 856 and the other of the source or the drain of the second transistor 857 are connected to a first electrode of a capacitor 861, and a second electrode of the capacitor 861 is connected to a first electrode of a third liquid crystal element 855. The first and second transistors are connected to a third wiring 860.

The second electrodes of the first liquid crystal element 853, the second liquid crystal element 854, and the third liquid crystal element 855 are connected to a common electrode.

The first wiring 858 and the second wiring 859 function as signal lines. Therefore, image signals are usually supplied to the first wiring 858 and the second wiring 859. However, this is not limited to this. A constant signal may be supplied regardless of the image. The third wiring 860 functions as a scan line.

The first switch 851 and the second switch 852 are not particularly limited as long as they function as switches. For example, transistors can be used.
When transistors are used as the first and second switches 852, the polarity thereof may be either P-channel type or N-channel type.

FIG. 28B shows a case where an N-channel transistor is used as a switch.
In (B), the gates of the first switch 851N and the second switch 852N are connected to a third wiring 760. The third wiring 860 functions as a scan line.

In addition, in FIG. 28, similarly to FIG. 1, etc., two scanning lines may be provided as shown in FIG. 49, and P-channel transistors may be used as switches.
As shown in the above, the liquid crystal element may be further divided into a plurality of elements.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

The first transistor 856 and the second transistor 857 are only required to function as a voltage dividing element, and the polarity of the first transistor 856 and the second transistor 857 may be either a P-channel type or an N-channel type.

28, the potential of the first electrode of the third liquid crystal element 855 can be lowered by the potential of the capacitor 861, as in FIG. 2 and the like.

Note that the first transistor 856 and the second transistor 857 are not limited to the configurations shown in the drawings. For example, one or both of the first transistor 856 and the second transistor 857 may have a multi-gate structure.

Note that the resistance values of the first transistor 856 and the second transistor 857 do not need to be constant, and may be set to vary depending on time or pixel. In order to change the resistance value, the potential of the gate of the first transistor 856 and the second transistor 857 functioning as a resistor may be changed depending on time or pixel.

Note that the first transistor 856 and the second transistor 857 are not limited to the configuration shown in the figure. For example, one or both of the first transistor 856 and the second transistor 857 may have a multi-gate structure. By using the multi-gate structure, the on-resistance of the first transistor 856 and the second transistor 857 can be made larger than that of the single-gate structure.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

Although the case where two voltage dividing elements are used has been described in Figs. 23 to 28, the present invention is not limited to this. It is possible to further improve the viewing angle characteristics by using more voltage dividing elements. As an example, when a voltage dividing element is added to Fig. 25, or when Fig. 9 is used,
FIG. 29 shows an example of a circuit formed by replacing a capacitance element with two voltage dividing elements shown in FIG. 30(J) connected in series.

In FIG. 29, a pixel 900 has a first switch 901, a second switch 902, a first liquid crystal element 903, a second liquid crystal element 904, a third liquid crystal element 905, a fourth liquid crystal element 906, a first transistor 907, a second transistor 908, and a third transistor 909.

The first wiring 910 is connected to the first electrode of the first liquid crystal element 903 and the first transistor 907.
The second wiring 911 is connected to one of the source or drain of the second transistor 907 through a first switch 901. The second wiring 911 is connected to a first electrode of a second liquid crystal element 904 and one of the source or drain of a third transistor 909 through a second switch 902. The other of the source or drain of the first transistor 907 is connected to a first electrode of a third liquid crystal element 905 and the other of the source or drain of a second transistor 908.
The other of the source or the drain of the first switch 901 is connected to a first electrode of a fourth liquid crystal element 906 and one of the source or the drain of a second transistor 908.
The gates of the first and second transistors of the switch 902 are connected to a third wiring 912 .

Second electrodes of the first liquid crystal element 903, the second liquid crystal element 904, the third liquid crystal element 905, and the fourth liquid crystal element 906 are connected to a common electrode.

The first wiring 910 and the second wiring 911 function as signal lines. Therefore, image signals are usually supplied to the first wiring 910 and the second wiring 911. However, this is not limiting. A constant signal may be supplied regardless of the image. The third wiring 912 functions as a scan line.

The first switch 901 and the second switch 902 are not particularly limited as long as they function as switches. For example, transistors can be used.
When a transistor is used as the second switch 902, the polarity thereof may be either a P-channel type or an N-channel type.

FIG. 28B shows a case where an N-channel transistor is used as a switch.
In (B), the gates of the first switch 901N and the second switch 902N are connected to a third wiring 912. The third wiring 912 functions as a scan line.

26, similarly to FIG. 1, two scanning lines may be provided as shown in FIG. 49, and P-channel transistors may be used as switches.
As shown in the above, the liquid crystal element may be further divided into a plurality of elements.

The switches are not limited to transistors, and various elements such as diodes can be used as switches.

The first to third transistors may be either P-channel or N-channel as long as they function as voltage dividing elements. N-channel transistors are used in FIG.

As shown in FIG. 29, only one of the first and second transistors in FIG. 25 may have a multi-gate structure.

Note that the gates of the first to third transistors are connected to the third wiring that controls the first and second switches; however, the present invention is not limited to this, and as described with reference to FIG. 27, the gates of the first to third transistors may be connected to a wiring different from the third wiring that controls the first and second switches.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

Note that the resistance values of the first transistor 907, the second transistor 908, and the third transistor 909 do not need to be constant, and may be set to vary depending on time or pixel. To change the resistance value, the potential of the gate of the third to fifth transistors functioning as resistors may be changed depending on time or pixel. Note that the first transistor 856 and the second transistor 857 are not limited to the configuration shown in the figure.

As described above, by providing each liquid crystal element with a different alignment state, the viewing angle can be widened.

An example of a top view of a pixel of a liquid crystal display device to which the present invention is applied is shown in Fig. 34. Also, Fig. 35 shows a circuit diagram of Fig. 34. Note that the same reference numerals are used for corresponding parts in Fig. 34 and Fig. 35.

The pixel 1020 shown in FIG. 34 includes a first conductive layer (
A first insulating film (not shown) is provided on the third wiring 1033, a semiconductor film is provided on the first insulating film, and a second conductive layer (the first wiring 1033 is shown by a hatched pattern) is provided on the semiconductor film.
A first conductive layer (indicated by a hatch pattern of 031) is provided on the first insulating film (not shown), and a third conductive layer (indicated by a hatch pattern of the first liquid crystal element 1023) is provided on the second insulating film.

In FIG. 35, a pixel 1020 includes a first transistor 1021 which is a first switch.
a second transistor 1022 which is a second switch; a first liquid crystal element 1023;
A second liquid crystal element 1024, a third liquid crystal element 1025, a fourth liquid crystal element 1026, a first capacitor element 1027, a second capacitor element 1030, a third capacitor element 1036, and a fourth
The semiconductor device further includes a capacitor 1036 , a third transistor 1028 , a fourth transistor 1029 , and a fifth transistor 1039 .

The first wiring 1031 is connected to the second wiring 1032 via the first to fifth transistors connected in series. The first to fifth transistors are connected to each other via the first to fourth transistors.
The first electrodes of the first to fourth liquid crystal elements are connected to the fourth wiring 1034 or the fifth wiring 1035. The second electrodes of the first to fourth liquid crystal elements are connected to the first electrodes of the capacitors connected to the fourth wiring 1034 or the fifth wiring 1035. The gates of the first to fifth transistors are connected to the third wiring 1033.

In addition, in Fig. 35, all the capacitance elements functioning as voltage dividing elements in Fig. 9B are replaced with transistors, and a storage capacitance is provided for each of the capacitance elements.
It can be said that this is a combination of Fig. 35 and Fig. 16. Therefore, the same configuration as Fig. 1 can be applied to Fig. 35. That is, the wiring functioning as the capacitance line may be shared with the common electrode as shown in Fig. 50, and the switch can be replaced with a transistor, and either an N-channel type or a P-channel type may be used for the transistor.

The first wiring 1031 and the second wiring 1032 function as signal lines.
An image signal is usually supplied to the first wiring 1031 and the second wiring 1032. However, this is not limited to this. A constant signal may be supplied regardless of the image.
The fourth wiring 1034 and the fifth wiring 1035 function as capacitance lines.

By providing a pixel as shown in the top view of FIG. 32, each liquid crystal element can have various alignment states, and a liquid crystal display device having a wider viewing angle can be provided.

In this embodiment, various drawings have been used to describe the present invention. However, a part or all of the contents described in each drawing may be applied to, combined with, or used in conjunction with a part or all of the contents described in another drawing.
Furthermore, in the figures described above, by combining each part with another part, many more configurations can be considered.
The description of this embodiment does not preclude this.

Similarly, a part or all of the contents described in each figure of this embodiment can be freely applied to, combined with, or replaced with a part or all of the contents described in the figures of another embodiment. Furthermore, by combining each part of the figures of this embodiment with parts of another embodiment, even more figures can be configured, and the description of this embodiment does not prevent this.

This embodiment shows an example of a case where a part or all of the contents described in the other embodiments are embodied, slightly modified, partially changed, improved, described in detail, applied, or related. Therefore, the contents described in the other embodiments can be freely applied to this embodiment, combined, or replaced.

(Embodiment 3)
In this embodiment, a structure and a manufacturing method of a transistor will be described.

51A to 51G are diagrams illustrating examples of structures and manufacturing methods of transistors.
51A illustrates an example of a structure of a transistor, and FIG. 51B to FIG. 51G illustrate an example of a method for manufacturing a transistor.

Note that the structures and manufacturing methods of the transistors are not limited to those shown in FIGS. 51A to 51G, and various structures and manufacturing methods can be used.

First, an example of a transistor structure will be described with reference to FIG.
51A is a cross-sectional view of a transistor having a plurality of different structures. Although a plurality of transistors having different structures are shown arranged side by side in Fig. 51A, this is an expression for explaining the structure of the transistor, and the transistors do not actually need to be arranged side by side as in Fig. 51A, and can be made differently as necessary.

Next, we will explain the characteristics of each layer that makes up the transistor.

The substrate 110111 may be a glass substrate such as barium borosilicate glass or aluminoborosilicate glass, a quartz substrate, a ceramic substrate, or a metal substrate including stainless steel.
It is also possible to use a substrate made of flexible synthetic resin such as plastic or acrylic, typified by polyethersulfone (PES). By using a flexible substrate, it is possible to manufacture a semiconductor device that can be bent. As long as the substrate is flexible, there is no significant limitation on the area and shape of the substrate.
For example, if a rectangular substrate with one side measuring 1 meter or more is used as the substrate 111, the productivity can be improved significantly. This is a major advantage over the case where a circular silicon substrate is used.

The insulating film 110112 functions as a base film. It is provided to prevent alkali metals such as Na or alkaline earth metals from the substrate 110111 from adversely affecting the characteristics of the semiconductor element. The insulating film 110112 can be provided as a single layer structure of an insulating film containing oxygen or nitrogen, such as silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy) (x>y), or silicon nitride oxide (SiNxOy) (x>y), or a laminate structure of these.
For example, when the insulating film 110112 is provided in a two-layer structure, a silicon nitride oxide film is provided as the first insulating film, and a silicon oxynitride film is provided as the second insulating film.
It is preferable to provide a silicon nitride oxide film as the second insulating film, and a silicon oxynitride film as the third insulating film.

The semiconductor layers 110113, 110114, and 110115 can be formed of an amorphous semiconductor or a semi-amorphous semiconductor (SAS). Alternatively, a polycrystalline semiconductor layer may be used. The SAS is a semiconductor having an intermediate structure between an amorphous structure and a crystalline structure (including single crystal and polycrystal), and having a third state that is stable in terms of free energy, and includes a crystalline region that has a short-range order and lattice distortion. At least a portion of the film has the following:
Crystal regions of 0.5 to 20 nm can be observed, and when silicon is the main component, the Raman spectrum is shifted to the lower wave number side than 520 cm ^-1 . In X-ray diffraction, diffraction peaks of (111) and (220) that are believed to be derived from the silicon crystal lattice are observed. At least 1 atomic % or more of hydrogen or halogen is contained to compensate for dangling bonds. SAS is formed by glow discharge decomposition (plasma CVD) of material gas. Material gases include SiH ₄ , Si ₂ H ₆ , SiH ₂ Cl ₂ , SiHC
It is possible to use _H2 , _SiCl4 , _SiF4 , etc. Alternatively, _GeF4 may be mixed. This material gas may be diluted with H2, or _H2 and one or more rare gas elements selected from He, Ar, Kr, and Ne. The dilution ratio is in the range of 2 to 1000 times. The pressure is in the range of approximately 0.1 Pa to 133 Pa, and the power supply frequency is 1 MHz to 120 MHz, preferably 13 MHz to 60 MHz. The substrate heating temperature may be 300°C or less. As impurity elements in the film, it is desirable that impurities of atmospheric components such as oxygen, nitrogen, and carbon are 1× ¹⁰²⁰ cm ^- 1 or less, and in particular, the oxygen concentration is 5× ¹⁰¹⁹ / ^cm3 or less, preferably 1× ¹⁰¹⁹ /cm3 or less.
Here, an amorphous semiconductor layer is formed from a material (e.g., SixGe1-x, etc.) containing silicon (Si) as a main component by using ^a known means (sputtering method, LPCVD method, plasma CVD method, etc.), and the amorphous semiconductor layer is crystallized by a known crystallization method such as a laser crystallization method, a thermal crystallization method using RTA or a furnace annealing furnace, or a thermal crystallization method using a metal element that promotes crystallization.

The insulating film 110116 is made of silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (
The insulating film 100 may have a single layer structure of an insulating film containing oxygen or nitrogen, such as silicon oxide nitride (SiOxNy) (x>y) or silicon nitride oxide (SiNxOy) (x>y), or a laminated structure of these.

The gate electrode 110117 can be a single layer conductive film, or a laminated structure of two or three layers of conductive films. A known conductive film can be used as the material of the gate electrode 110117. For example, a single film of an element such as tantalum (Ta), titanium (Ti), molybdenum (Mo), tungsten (W), chromium (Cr), or silicon (Si), or a nitride film of the above element (typically a tantalum nitride film, a tungsten nitride film, or a titanium nitride film), or
It is possible to use an alloy film of a combination of the above elements (typically, a Mo-W alloy or a Mo-Ta alloy), or a silicide film of the above elements (typically, a tungsten silicide film or a titanium silicide film), etc. The above-mentioned simple films, nitride films, alloy films, silicide films, etc. may be used as a single layer or may be used in a laminated form.

The insulating film 110118 is formed by a known method (such as a sputtering method or a plasma CVD method) using a silicon oxide (SiOx), silicon nitride (SiNx), or silicon oxynitride (SiOxNy) (x>y).
, silicon oxynitride (SiNxOy) (x>y) or other insulating films containing oxygen or nitrogen, or DLC (
The insulating layer 11 may have a single layer structure of a film containing carbon such as diamond-like carbon, or a laminate structure of these films.

The insulating film 110119 is made of siloxane resin, silicon oxide (SiOx), silicon nitride (
SiNx), silicon oxynitride (SiOxNy) (x>y), silicon nitride oxide (SiNxOy)
It can be provided as a single layer or a laminated structure made of an insulating film containing oxygen or nitrogen such as (x>y), a film containing carbon such as DLC (diamond-like carbon), or an organic material such as epoxy, polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, etc. The siloxane resin corresponds to a resin containing Si-O-Si bonds.
Siloxane has a skeletal structure formed by the bond between silicon (Si) and oxygen (O). An organic group containing at least hydrogen (e.g., an alkyl group, an aromatic hydrocarbon) is used as a substituent. A fluoro group can also be used as a substituent. Alternatively, an organic group containing at least hydrogen and a fluoro group can be used as a substituent. It is also possible to provide an insulating film 110119 directly so as to cover the gate electrode 110117 without providing an insulating film 110118.

The conductive film 110123 is made of Al, Ni, C, W, Mo, Ti, Pt, Cu, Ta, Au, M
For example, a film of a single element such as n, a nitride film of the element, an alloy film of a combination of the elements, or a silicide film of the element can be used. For example, an alloy containing a plurality of the elements can be an Al alloy containing C and Ti, an Al alloy containing Ni,
An Al alloy containing C and Ni, an Al alloy containing C and Mn, etc. can be used. For example, when a laminated structure is provided, a structure in which Al is sandwiched between Mo or Ti, etc. can be used. This can improve the resistance of Al to heat and chemical reactions.

Next, with reference to the cross-sectional view of transistors having a plurality of different structures shown in FIG. 51A, features of each structure will be described.

110101 is a single drain transistor and can be manufactured by a simple method.
The semiconductor layer 11011 has the advantage of being manufactured at low cost and with a high yield.
The semiconductor layers 110113 and 110115 have different impurity concentrations, and the semiconductor layer 110113 is used as a channel region, and the semiconductor layer 110115 is used as a source region and a drain region.
By controlling the amount of impurities, the resistivity of the semiconductor layer can be controlled.
The electrical connection state with 123 can be made closer to an ohmic connection. In addition, as a method for producing semiconductor layers with different amounts of impurities, a method of doping the semiconductor layer with impurities using the gate electrode 110117 as a mask can be used.

The transistor 110102 has a gate electrode 110117 with a taper angle of a certain degree or more, and can be manufactured by a simple method, which has the advantage of low manufacturing cost and high manufacturing yield. Here, the semiconductor layers 110113, 110114, and 110115 have different impurity concentrations, the semiconductor layer 110113 being a channel region, the semiconductor layer 110114 being a lightly doped drain (LDD) region, and the semiconductor layer 110
115 is used as a source region and a drain region. In this way, by controlling the amount of impurities, the resistivity of the semiconductor layer can be controlled. The electrical connection state between the semiconductor layer and the conductive film 110123 can be made closer to an ohmic connection. Since the LDD region is provided, a high electric field is unlikely to be applied inside the transistor, and deterioration of the element due to hot carriers can be suppressed. As a method for separately producing semiconductor layers with different amounts of impurities, the gate electrode 110
A method of doping impurities into the semiconductor layer using 117 as a mask can be used.
In 10102, since the gate electrode 110117 has a taper angle of a certain degree or more, it is possible to provide a gradient in the concentration of the impurity that passes through the gate electrode 110117 and is doped into the semiconductor layer, making it possible to easily form an LDD region.

110103 is a transistor in which the gate electrode 110117 is made up of at least two layers, and the lower gate electrode is longer than the upper gate electrode. In this specification, the shapes of the upper and lower gate electrodes are called hat-shaped.
Since the shape of 117 is hat-shaped, the LDD region can be formed without adding a photomask.
The structure overlapping with 0117 is specifically called the GOLD structure (Gate Overlapped
The gate electrode 110117 may be formed in a hat shape by the following method.

First, when patterning the gate electrode 110117, the lower gate electrode and the upper gate electrode are etched by dry etching to give them a tapered shape on the side. Then, the upper gate electrode is processed by anisotropic etching so that the slope becomes nearly vertical. This forms a gate electrode with a hat-shaped cross section. Then, the etching is repeated twice.
A semiconductor layer 1101 used as a channel region by doping with an impurity element.
13, a semiconductor layer 110114 to be used as an LDD region, and a semiconductor layer 110115 to be used as a source electrode and a drain electrode are formed.

The LDD region overlapping the gate electrode 110117 is called the Lov region.
The LDD region that does not overlap with 0117 is called the Loff region.
The f region has a high effect of suppressing the off-current value, but has a low effect of reducing the electric field near the drain and preventing the deterioration of the on-current value due to hot carriers. On the other hand, the Lov region is effective in reducing the electric field near the drain and preventing the deterioration of the on-current value, but has a low effect of suppressing the off-current value. Therefore, it is preferable to manufacture transistors having a structure according to the characteristics required for each of various circuits. For example, when the semiconductor device is used as a display device, it is preferable to use a transistor having an Loff region as the pixel transistor in order to suppress the off-current value.
On the other hand, for the transistors in the peripheral circuits, it is preferable to use transistors having a Lov region in order to reduce the electric field near the drain and prevent deterioration of the on-current value.

110104 is in contact with the side of the gate electrode 110117 and is a side wall 110121
By providing the sidewall 110121, the region overlapping with the sidewall 110121 can be made into an LDD region.

110105 is a method for forming LDD (Lof) doped semiconductor layers using a mask.
f) A transistor in which an LDD region is formed. By doing so, the LDD region can be reliably formed, and the off-state current value of the transistor can be reduced.

110106 is a semiconductor layer that is doped using a mask to create an LDD (Lov
In this way, the LDD region can be formed reliably, the electric field in the vicinity of the drain of the transistor can be relaxed, and the deterioration of the on-current value can be reduced.

Next, an example of a method for manufacturing a transistor will be described with reference to Figures 51 (B) to (G).

Note that the structure and manufacturing method of the transistor are not limited to those shown in FIG. 51, and various structures and manufacturing methods can be used.

In this embodiment, the surface of the substrate 110111, the surface of the insulating film 110112, the surface of the semiconductor layer 110113, the surface of the semiconductor layer 110114, the surface of the semiconductor layer 110115, and the insulating film 110116 are formed on the surface of the substrate 110111.
10116, the surface of the insulating film 110118, or the surface of the insulating film 110119,
By performing oxidation or nitridation using plasma treatment, the semiconductor layer or the insulating film can be oxidized or nitrided. In this manner, by oxidizing or nitriding the semiconductor layer or the insulating film using plasma treatment, the surface of the semiconductor layer or the insulating film can be modified and an insulating film that is denser than an insulating film formed by a CVD method or a sputtering method can be formed, so that defects such as pinholes can be suppressed and the characteristics of the semiconductor device can be improved.

First, the surface of the substrate 110111 is cleaned using hydrofluoric acid (HF), alkali or pure water.
The substrate 110111 may be a glass substrate such as barium borosilicate glass or aluminoborosilicate glass, a quartz substrate, a ceramic substrate, or a metal substrate including stainless steel.
It is also possible to use a substrate made of flexible synthetic resin such as acrylic or plastic such as polyethersulfone (PES).
The case where a glass substrate is used as 0111 is shown.

Here, a plasma treatment may be performed on the surface of the substrate 110111 to oxidize or nitride the surface of the substrate 110111, thereby forming an oxide film or a nitride film on the surface of the substrate 110111 (FIG. 51B). An insulating film such as an oxide film or a nitride film formed on the surface by performing a plasma treatment is also referred to as a plasma-treated insulating film below. In FIG. 51B,
The insulating film 131 is a plasma treatment insulating film. In general, when a semiconductor element such as a thin film transistor is provided on a substrate such as glass or plastic, impurity elements such as alkali metals or alkaline earth metals such as Na contained in the glass or plastic may mix with and contaminate the semiconductor element, thereby affecting the characteristics of the semiconductor element. However, by nitriding the surface of the substrate made of glass or plastic, it is possible to prevent impurity elements such as alkali metals or alkaline earth metals such as Na contained in the substrate from mixing with the semiconductor element.

In addition, when the surface is oxidized by plasma treatment, the surface is oxidized in an oxygen atmosphere (for example, oxygen (O ₂
) and a rare gas (containing at least one of He, Ne, Ar, Kr, and Xe) atmosphere, or oxygen and hydrogen (H ₂ ) and a rare gas atmosphere, or dinitrogen monoxide and a rare gas atmosphere)
On the other hand, when nitriding the semiconductor layer by plasma treatment, the plasma treatment is performed in a nitrogen atmosphere (for example, an atmosphere of nitrogen (N ₂ ) and a rare gas (containing at least one of He, Ne, Ar, Kr, and Xe), or an atmosphere of nitrogen, hydrogen, and a rare gas, or an atmosphere of NH ₃ and a rare gas). For example, Ar can be used as the rare gas. Alternatively, a mixed gas of Ar and Kr may be used. Therefore, the plasma treatment insulating film contains the rare gas (containing at least one of He, Ne, Ar, Kr, and Xe) used in the plasma treatment. For example, when Ar is used, the plasma treatment insulating film contains Ar.

The plasma treatment is carried out in an atmosphere of the above gas with an electron density of 1×10 ¹¹ cm ⁻³ or more.
It is preferable that the plasma is irradiated at a temperature of 1×10 ¹³ cm ⁻³ or less and the plasma electron temperature is 0.5 eV or more and 1.5 eV or less. Since the plasma has a high electron density and the electron temperature near the object to be treated is low, damage to the object to be treated by the plasma can be prevented. Since the plasma has a high electron density of 1×10 ¹¹ cm ⁻³ or more, the oxide or nitride film formed by oxidizing or nitriding the object to be irradiated using the plasma treatment has a uniform film thickness and the like compared to films formed by CVD, sputtering, etc., and can form a dense film. Alternatively, since the plasma electron temperature is low at 1 eV or less, the oxidation or nitridation treatment can be performed at a lower temperature compared to conventional plasma treatments and thermal oxidation methods. For example, the oxidation or nitridation treatment can be performed sufficiently even if the plasma treatment is performed at a temperature 100 degrees or more lower than the strain point temperature of the glass substrate. Note that a high frequency such as microwaves (2.45 GHz) can be used as the frequency for forming the plasma. Note that unless otherwise specified below, the plasma treatment is performed under the above conditions.

In FIG. 51B, the surface of the substrate 110111 is subjected to plasma treatment to form a plasma-treated insulating film.
This also includes the case where no plasma-treated insulating film is formed on the surface of the substrate 1.

In addition, although the plasma processing insulating film formed by plasma processing the surface of the processing object is not shown in FIGS. 51C to 51G, in this embodiment, the substrate 11
0111, insulating film 110112, semiconductor layer 110113, 110114, 110115,
This also includes the case where a plasma-treated insulating film is formed on the surface of insulating film 110116, insulating film 110118, or insulating film 110119 by performing plasma treatment.

Next, an insulating film 110112 is formed on the substrate 110111 by a known method (sputtering, LPCVD, plasma CVD, or the like) (FIG. 51C). The insulating film 110112 can be made of silicon oxide (SiOx) or silicon oxynitride (SiOxNy) (x>y).

Here, a plasma-treated insulating film may be formed on the surface of the insulating film 110112 by performing a plasma treatment on the surface of the insulating film 110112 and oxidizing or nitriding the insulating film 110112. By oxidizing the surface of the insulating film 110112, the surface of the insulating film 110112 can be modified to obtain a dense film with few defects such as pinholes. By oxidizing the surface of the insulating film 110112, a plasma-treated insulating film with a low content of N atoms can be formed, and when a semiconductor layer is provided on the plasma-treated insulating film, the interface characteristics between the plasma-treated insulating film and the semiconductor layer are improved. Note that the plasma-treated insulating film is formed by oxidizing the rare gas (
The plasma treatment may be performed under the above-mentioned conditions.

Next, island-shaped semiconductor layers 110113 and 110114 are formed on the insulating film 110112 (
FIG. 51(D)). The island-shaped semiconductor layers 110113 and 110114 are formed by depositing silicon (S) on the insulating film 110112 using a known method (sputtering, LPCVD, plasma CVD, etc.).
i) as a main component (e.g., Si _x Ge _1-x, etc.), an amorphous semiconductor layer is formed, and the amorphous semiconductor layer is crystallized and selectively etched. The amorphous semiconductor layer can be crystallized by a known crystallization method such as a laser crystallization method, a thermal crystallization method using an RTA or furnace annealing furnace, a thermal crystallization method using a metal element that promotes crystallization, or a combination of these methods. Here, the end of the island-shaped semiconductor layer is provided in a shape close to a right angle (θ=85 to 100°). Alternatively, the semiconductor layer 110114 that becomes the low concentration drain region can be doped with an impurity using a mask.
The signal may be generated by pinging.

Here, the surfaces of the semiconductor layers 110113 and 110114 are subjected to plasma treatment, and the semiconductor layer 1
The surfaces of the semiconductor layers 11011 and 110114 are oxidized or nitrided.
A plasma-treated insulating film may be formed on the surfaces of the semiconductor layers 11, 110, and 114.
When Si is used as the semiconductor layers 110113 and 110114, silicon oxide (SiOx) or silicon nitride (SiNx) is formed as the plasma treatment insulating film. Alternatively, the semiconductor layers 110113 and 110114 may be oxidized by plasma treatment and then nitrided by performing plasma treatment again. In this case, silicon oxide (SiOx) is formed in contact with the semiconductor layers 110113 and 110114, and silicon oxynitride (SiNxOy) (x>
When the semiconductor layer is oxidized by plasma treatment, the plasma treatment is performed in an oxygen atmosphere (for example, an atmosphere of oxygen (O ₂ ) and a rare gas (containing at least one of He, Ne, Ar, Kr, and Xe), or an atmosphere of oxygen, hydrogen (H ₂ ), and a rare gas, or an atmosphere of nitrous oxide and a rare gas). On the other hand, when the semiconductor layer is nitrided by plasma treatment, the plasma treatment is performed in a nitrogen atmosphere (for example, an atmosphere of nitrogen (N ₂ ) and a rare gas (containing at least one of He, Ne, Ar, Kr, and Xe).
e) atmosphere, or nitrogen, hydrogen and rare gas atmosphere, or NH
The plasma treatment is performed in an atmosphere of Ar3 and a rare gas. For example, Ar can be used as the rare gas. Alternatively, a mixed gas of Ar and Kr can be used. Therefore, the plasma-treated insulating film contains the rare gas (containing at least one of He, Ne, Ar, Kr, and Xe) used in the plasma treatment. For example, when Ar is used, the plasma-treated insulating film contains Ar and Kr.
It contains r.

Next, an insulating film 110116 is formed (FIG. 51E). The insulating film 110116 is formed by depositing silicon oxide (SiOx
), silicon nitride (SiNx), silicon oxynitride (SiOxNy) (x>y), silicon nitride oxide (
The insulating film 110116 may have a single layer structure of an insulating film containing oxygen or nitrogen, such as SiNxOy (x>y), or a laminate structure of these. When the surfaces of the semiconductor layers 110113 and 110114 are subjected to plasma treatment to form a plasma-treated insulating film on the surfaces of the semiconductor layers 110113 and 110114, the plasma-treated insulating film can also be used as the insulating film 110116.

Here, a plasma treatment may be performed on the surface of the insulating film 110116 to oxidize or nitride the surface of the insulating film 110116, thereby forming a plasma-treated insulating film on the surface of the insulating film 110116. Note that the plasma-treated insulating film may be formed by oxidizing or nitriding the surface of the insulating film 110116 using a rare gas (He, Ne,
The plasma treatment can be carried out under the above-mentioned conditions.

Alternatively, the insulating film 110116 may be oxidized by once performing a plasma treatment in an oxygen atmosphere, and then nitrided by performing a plasma treatment again in a nitrogen atmosphere. In this manner, by performing a plasma treatment on the insulating film 110116 and oxidizing or nitriding the surface of the insulating film 110116, the surface of the insulating film 110116 can be modified to form a dense film. The insulating film obtained by the plasma treatment is denser and has fewer defects such as pinholes compared to insulating films formed by a CVD method or a sputtering method, and therefore the characteristics of the thin film transistor can be improved.

Next, a gate electrode 110117 is formed (FIG. 51(F)). The gate electrode 110117 can be formed by using known means (sputtering, LPCVD, plasma CVD, etc.).

In 110101, after forming a gate electrode 110117, impurity doping is performed to form a semiconductor layer 110115 to be used as a source region and a drain region.

In 110102, by forming a gate electrode 110117 and then doping with impurities, it is possible to form 110114 to be used as an LDD region and semiconductor layers 110115 to be used as the semiconductor layer source and drain regions.

In 110103, by forming a gate electrode 110117 and then doping with impurities, it is possible to form 110114 to be used as an LDD region and semiconductor layers 110115 to be used as the semiconductor layer source and drain regions.

In the case of 110104, a side wall 110121 is formed on the side of the gate electrode 110117.
After forming the 110114, impurity doping is performed to form the 110114 used as the LDD region.
Then, a semiconductor layer 110115 to be used as a semiconductor layer source region and drain region can be formed.

The side wall 110121 is made of silicon oxide (SiOx) or silicon nitride (SiNx).
The method of forming the side wall 110121 on the side surface of the gate electrode 110117 can be, for example, a method of forming the gate electrode 110117 and then depositing silicon oxide (
A method can be used in which a silicon oxide (SiOx) or silicon nitride (SiNx) film is formed by a known method, and then the silicon oxide (SiOx) or silicon nitride (SiNx) film is etched by anisotropic etching. By doing so, silicon oxide (SiO
Since a silicon nitride (SiNx) film can be left behind, a side wall 110121 can be formed on the side of the gate electrode 110117.

In the case of 110105, a mask 110122 is formed so as to cover the gate electrode 110117, and then impurity doping is performed to form a region 110122 to be used as an LDD (Loff) region.
110 and a semiconductor layer 110115 to be used as a semiconductor layer source region and a drain region can be formed.

In 110106, by forming a gate electrode 110117 and then doping with impurities, it is possible to form 110114 to be used as an LDD (Lov) region and semiconductor layers 110115 to be used as the semiconductor layer source and drain regions.

Next, an insulating film 110118 is formed (FIG. 51(G)). The insulating film 110118 is formed by depositing silicon oxide (SiOx), silicon nitride (S
iNx), silicon oxynitride (SiOxNy) (x>y), silicon nitride oxide (SiNxOy) (
The insulating film may have a single layer structure of an insulating film containing oxygen or nitrogen (x>y) or a film containing carbon such as DLC (diamond-like carbon), or a laminate structure of these.

Here, a plasma treatment may be performed on the surface of the insulating film 110118 to oxidize or nitride the surface of the insulating film 110118, thereby forming a plasma-treated insulating film on the surface of the insulating film 110118. Note that the plasma-treated insulating film may be formed by oxidizing or nitriding the surface of the insulating film 110118 using a rare gas (He, Ne,
The plasma treatment can be carried out under the above-mentioned conditions.

Next, the insulating film 110119 is formed. The insulating film 110119 can be formed by known means (such as sputtering or plasma CVD) using an insulating film containing oxygen or nitrogen, such as silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy) (x>y), or silicon nitride oxide (SiNxOy) (x>y), or a film containing carbon, such as DLC (diamond-like carbon), or can be formed in a single-layer structure of organic materials, such as epoxy, polyimide, polyamide, polyvinylphenol, benzocyclobutene, or acrylic, or a siloxane resin, or a laminated structure thereof. The siloxane resin corresponds to a resin containing Si-O-Si bonds. The skeletal structure of siloxane is formed by bonds between silicon (Si) and oxygen (O). An organic group containing at least hydrogen (for example, an alkyl group, an aromatic hydrocarbon) is used as the substituent. A fluoro group can also be used as the substituent. Alternatively, an organic group containing at least hydrogen and a fluoro group may be used as the substituent. The plasma-treated insulating film contains a rare gas (containing at least one of He, Ne, Ar, Kr, and Xe) used in the plasma treatment. For example, when Ar is used, the plasma-treated insulating film contains Ar.

When the insulating film 110119 is made of an organic material such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, or acrylic, or a siloxane resin, the insulating film 110119
The surface of the insulating film 110119 can be modified by oxidizing or nitriding the surface of the insulating film 110119 by plasma treatment. By modifying the surface, the strength of the insulating film 110119 is improved, and it is possible to reduce physical damage such as cracks occurring during the formation of openings and film loss during etching. By modifying the surface of the insulating film 110119, the insulating film 110
When a conductive film 110 or 123 is formed on the insulating film 119, the adhesion between the conductive film 110 and the insulating film 123 is improved. For example,
When siloxane resin is used as the insulating film 110119 and nitridation is performed using plasma treatment, the surface of the siloxane resin is nitrided to form a plasma-treated insulating film containing nitrogen or a rare gas, and the physical strength is improved.

Next, in order to form a conductive film 110123 electrically connected to the semiconductor layer 110115,
Contact holes are formed in the insulating films 110119, 110118, and 110116. The contact holes may be tapered.
The coverage of the conductive film 110123 can be improved.

Figure 55 shows the cross-sectional structure of a bottom-gate transistor and the cross-sectional structure of a capacitance element.

A first insulating film (insulating film 110502) is formed over the entire surface of a substrate 110501. The first insulating film has a function of preventing impurities from the substrate side from affecting the semiconductor layer and causing changes in the properties of the transistor. In other words, the first insulating film has a function as a base film. Therefore, a highly reliable transistor can be manufactured. Note that the first insulating film may be a silicon oxide film, a silicon nitride film, or a silicon oxynitride film (SiOxNy
) or a laminate thereof can be used.

A first conductive layer (conductive layer 110503 and conductive layer 110504) is formed on the first insulating film. The conductive layer 110503 includes a portion that functions as a gate electrode of the transistor 110520. The conductive layer 110504 includes a portion that functions as a first electrode of the capacitor element 110521. The first conductive layer may be formed of Ti, Mo, Ta, Cr, W, Al, or N.
For example, Zn, Fe, Ba, Ge, or alloys thereof can be used. Alternatively, a laminate of these elements (including alloys) can be used.

A second insulating film (insulating film 110504) is formed so as to cover at least the first conductive layer. The second insulating film functions as a gate insulating film. As the second insulating film, a single layer such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film (SiOxNy) or a laminate of these can be used.

It is preferable to use a silicon oxide film as the second insulating film in contact with the semiconductor layer, because this reduces the trap levels at the interface between the semiconductor layer and the second insulating film.

When the second insulating film is in contact with Mo, it is desirable to use a silicon oxide film as the second insulating film in the portion in contact with Mo, because the silicon oxide film does not oxidize Mo.

A semiconductor layer is formed by photolithography, inkjet printing, printing, or the like on a portion of the second insulating film that overlaps with the first conductive layer. The portion of the semiconductor layer extends to a portion of the second insulating film that does not overlap with the first conductive layer. The semiconductor layer is a channel formation region (channel formation region 1105
110505), LDD regions (LDD region 110508, LDD region 110509), and impurity regions (impurity region 110505, impurity region 110506, impurity region 110507). The channel formation region 110510 functions as a channel formation region of the transistor 110520. The LDD region 110508 and the LDD region 110509 function as LDD regions of the transistor 110520. Note that the LDD region 110508 and the LDD region 110509 are not necessarily required. The impurity region 110505 is a region for forming a channel of the transistor 110520.
The impurity region 1 includes a portion that functions as one of the source electrode and the drain electrode of 0520.
An impurity region 110506 includes a portion functioning as the other of the source electrode and the drain electrode of the transistor 110520. An impurity region 110507 includes a portion functioning as a second electrode of the capacitor 110521.

A third insulating film (insulating film 110511) is formed on the entire surface. A contact hole is selectively formed in a part of the third insulating film. The insulating film 110511 functions as an interlayer film. As the third insulating film, an inorganic material (silicon oxide, silicon nitride, silicon oxynitride, etc.) or a low dielectric constant organic compound material (photosensitive or non-photosensitive organic resin material) can be used. Alternatively, a material containing siloxane can be used. Note that siloxane is a material whose skeletal structure is formed by bonding silicon (Si) and oxygen (O). As a substituent, an organic group containing at least hydrogen (e.g., an alkyl group, an aromatic hydrocarbon) is used. Alternatively, a fluoro group may be used as a substituent. Alternatively, an organic group containing at least hydrogen and a fluoro group may be used as a substituent.

A second conductive layer (conductive layer 110512 and conductive layer 110513) is formed on the third insulating film. The conductive layer 110512 is connected to the other of the source electrode and drain electrode of the transistor 110520 through a contact hole formed in the third insulating film. Therefore, the conductive layer 110512 includes a portion that functions as the other of the source electrode and drain electrode of the transistor 110520. The conductive layer 110513 includes a portion that functions as a first electrode of the capacitor 110521. Note that the second conductive layer may be formed of Ti, Mo, Ta,
, Cr, W, Al, Nd, Cu, Ag, Au, Pt, NA-Si, Zn, Fe, Ba, G
Alternatively, a laminate of these elements (including alloys) may be used.

Note that various insulating films or various conductive films may be formed as a step after the second conductive layer is formed.

The structures of a transistor and a capacitor in the case where an amorphous silicon (a-Si:H) film is used for the semiconductor layer of the transistor will be described.

Figure 52 shows the cross-sectional structure of a top-gate transistor and the cross-sectional structure of a capacitance element.

A first insulating film (insulating film 110202) is formed over the entire surface of a substrate 110201. The first insulating film has a function of preventing impurities from the substrate side from affecting the semiconductor layer and causing changes in the properties of the transistor. In other words, the first insulating film has a function as a base film. Therefore, a highly reliable transistor can be manufactured. Note that the first insulating film may be a silicon oxide film, a silicon nitride film, or a silicon oxynitride film (SiOxNy
) or a laminate thereof can be used.

It is not always necessary to form the first insulating film. In this case, the number of steps can be reduced. The manufacturing cost can be reduced. Since the structure can be simplified, the yield can be improved.

A first conductive layer (conductive layer 110203, conductive layer 110204, and conductive layer 110205) is formed on the first insulating film. The conductive layer 110203 includes a portion that functions as one of the source electrode and drain electrode of the transistor 110220.
The conductive layer 110204 includes a portion that functions as the other of the source electrode and the drain electrode of the transistor 110220. The conductive layer 110205 includes a portion that functions as a first electrode of the capacitor 110221. The first conductive layer may be formed of Ti, Mo, Ta, Cr, W, Al, or N.
For example, Zn, Fe, Ba, Ge, or alloys thereof can be used. Alternatively, a laminate of these elements (including alloys) can be used.

A first semiconductor layer (semiconductor layer 110
The semiconductor layer 110206 includes a portion that functions as one of a source electrode and a drain electrode. The semiconductor layer 110207 includes
The first semiconductor layer includes a portion that functions as the other of the source electrode and the drain electrode. The first semiconductor layer may be made of silicon or the like containing phosphorus or the like.

Between the conductive layer 110203 and the conductive layer 110204 and on the first insulating film,
The semiconductor layer (semiconductor layer 110208) is formed.
A part of the semiconductor layer 110208 extends onto the conductive layer 110203 and onto the conductive layer 110204. The semiconductor layer 110208 includes a portion that functions as a channel region of the transistor 110220. Note that as the second semiconductor layer, a semiconductor layer having non-crystallinity such as amorphous silicon (a-Si:H), a semiconductor layer such as a microcrystalline semiconductor (μ-Si:H), or the like can be used.

A second insulating film (
The first insulating film is a gate insulating film 110209 and the second insulating film is a gate insulating film 110210.
As the second insulating film, a single layer of a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiOxNy), or the like, or a laminate of these films can be used.

It is preferable to use a silicon oxide film as the second insulating film in contact with the second semiconductor layer, because this reduces trap levels at the interface between the second semiconductor layer and the second insulating film.

When the second insulating film is in contact with Mo, it is desirable to use a silicon oxide film as the second insulating film in the portion in contact with Mo, because the silicon oxide film does not oxidize Mo.

A second conductive layer (conductive layer 110211 and conductive layer 110212) is formed on the second insulating film. The conductive layer 110211 includes a portion that functions as a gate electrode of a transistor 110220. The conductive layer 110212 functions as a second electrode of a capacitor element 110221 or as a wiring. The second conductive layer may be formed of Ti, Mo, Ta, Cr, W, A, or the like.
For example, the following elements can be used: I, Nd, Cu, Ag, Au, Pt, NA-Si, Zn, Fe, Ba, Ge, etc., or alloys thereof. Alternatively, a laminate of these elements (including alloys) can be used.

Note that various insulating films or various conductive films may be formed as a step after the second conductive layer is formed.

53 shows a cross-sectional structure of an inverted staggered (bottom gate) transistor and a cross-sectional structure of a capacitor. In particular, the transistor shown in FIG. 53 has a structure called a channel etch type.

A first insulating film (insulating film 110302) is formed over the entire surface of a substrate 110301. The first insulating film has a function of preventing impurities from the substrate side from affecting the semiconductor layer and causing changes in the properties of the transistor. In other words, the first insulating film has a function as a base film. Therefore, a highly reliable transistor can be manufactured. Note that the first insulating film may be a silicon oxide film, a silicon nitride film, or a silicon oxynitride film (SiOxNy
) or a laminate thereof can be used.

It is not always necessary to form the first insulating film. In this case, the number of steps can be reduced. The manufacturing cost can be reduced. Since the structure can be simplified, the yield can be improved.

A first conductive layer (conductive layer 110303 and conductive layer 110304) is formed on the first insulating film. The conductive layer 110303 includes a portion that functions as a gate electrode of a transistor 110320. The conductive layer 110304 includes a portion that functions as a first electrode of a capacitance element 110321. The first conductive layer may be made of Ti, Mo, TB, Cr, W, Bl, or N.
The material may be selected from the group consisting of Zn, Fe, Zn, B, Ge, Pt, NA-Si, Zn, Fe, BB, Ge, and alloys thereof. Alternatively, a laminate of these elements (including alloys) may be used.

A second insulating film (insulating film 110302) is formed so as to cover at least the first conductive layer. The second insulating film functions as a gate insulating film. As the second insulating film, a single layer such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film (SiOxNy) or a laminate of these can be used.

It is preferable to use a silicon oxide film as the second insulating film in contact with the semiconductor layer, because this reduces the trap levels at the interface between the semiconductor layer and the second insulating film.

When the second insulating film is in contact with Mo, it is desirable to use a silicon oxide film as the second insulating film in the portion in contact with Mo, because the silicon oxide film does not oxidize Mo.

A first semiconductor layer (semiconductor layer 11) is formed on a part of the second insulating film overlapping with the first conductive layer by photolithography, inkjet printing, printing, or the like.
A part of the semiconductor layer 110308 extends to a portion of the second insulating film that is not overlapped with the first conductive layer.
The semiconductor layer 110306 includes a portion that functions as a channel region of the transistor 110320. Note that the semiconductor layer 110306 can be a semiconductor layer having non-crystallinity such as amorphous silicon (A-Si:H), a semiconductor layer such as a microcrystalline semiconductor (μ-Si:H), or the like.

A second semiconductor layer (semiconductor layer 110307 and semiconductor layer 110) is formed on a portion of the first semiconductor layer.
The semiconductor layer 110307 includes a portion that functions as one of the source electrode and drain electrode. The semiconductor layer 110308 includes a portion that functions as the other of the source electrode and drain electrode. Note that silicon containing phosphorus or the like can be used as the second conductor layer.

A second conductive layer (conductive layer 110309, conductive layer 110309) is formed on the second semiconductor layer and the second insulating film.
The conductive layer 110309 includes a portion that functions as one of the source electrode and drain electrode of the transistor 110320. The conductive layer 110310 includes a portion that functions as the other of the source electrode and drain electrode of the transistor 110320. The conductive layer 110312 includes a portion that functions as a second electrode of the capacitor 110321. The second conductive layer may be formed of Ti, Mo, Ta, Cr, W, Al, or N.
For example, Zn, Fe, Ba, Ge, or alloys thereof can be used. Alternatively, a laminate of these elements (including alloys) can be used.

Note that various insulating films or various conductive films may be formed as a step after the second conductive layer is formed.

Here, an example of a process that is characteristic of a channel-etch type transistor will be described. The first semiconductor layer and the second semiconductor layer can be formed using the same mask. Specifically,
The first semiconductor layer and the second semiconductor layer are formed successively using the same mask.

Another example of a process for forming a channel-etched transistor will be described. A channel region of the transistor can be formed without using a new mask. Specifically,
After the second conductive layer is formed, a portion of the second semiconductor layer is removed using the second conductive layer as a mask, or the same mask as the second conductive layer is used to remove a portion of the second semiconductor layer, and the first semiconductor layer formed under the removed second semiconductor layer becomes a channel region of the transistor.

54 shows a cross-sectional structure of an inverted staggered (bottom gate) transistor and a cross-sectional structure of a capacitor. In particular, the transistor shown in FIG. 54 has a structure called a channel protection type (channel stop type).

A first insulating film (insulating film 110402) is formed over the entire surface of a substrate 110401. The first insulating film has a function of preventing impurities from the substrate side from affecting the semiconductor layer and causing changes in the properties of the transistor. In other words, the first insulating film has a function as a base film. Therefore, a highly reliable transistor can be manufactured. Note that the first insulating film may be a silicon oxide film, a silicon nitride film, or a silicon oxynitride film (SiOxNy
) or a laminate thereof can be used.

It is not always necessary to form the first insulating film. In this case, the number of steps can be reduced. The manufacturing cost can be reduced. Since the structure can be simplified, the yield can be improved.

A first conductive layer (conductive layer 110403 and conductive layer 110404) is formed on the first insulating film. The conductive layer 110403 includes a portion that functions as a gate electrode of the transistor 110420. The conductive layer 110404 includes a portion that functions as a first electrode of the capacitor element 110421. The first conductive layer may be formed of Ti, Mo, TC, Cr, W, Cl, or N.
For example, the following may be used: Zn, Cu, Cg, Cu, Pt, NC, Si, Zn, Fe, CC, Ge, or alloys thereof. Alternatively, a laminate of these elements (including alloys) may be used.

A second insulating film (insulating film 110402) is formed so as to cover at least the first conductive layer. The second insulating film functions as a gate insulating film. As the second insulating film, a single layer such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film (SiOxNy) or a laminate of these can be used.

It is preferable to use a silicon oxide film as the second insulating film in contact with the semiconductor layer, because this reduces the trap levels at the interface between the semiconductor layer and the second insulating film.

When the second insulating film is in contact with Mo, it is desirable to use a silicon oxide film as the second insulating film in the portion in contact with Mo, because the silicon oxide film does not oxidize Mo.

A first semiconductor layer (semiconductor layer 11) is formed on a part of the second insulating film overlapping with the first conductive layer by photolithography, inkjet printing, printing, or the like.
A part of the semiconductor layer 110408 extends to a portion of the second insulating film that is not overlapped with the first conductive layer.
The semiconductor layer 110406 includes a portion functioning as a channel region of the transistor 110420. Note that the semiconductor layer 110406 can be a semiconductor layer having non-crystalline properties such as amorphous silicon (C-Si:H), a semiconductor layer such as a microcrystalline semiconductor (μ-Si:H), or the like.

A third insulating film (insulating film 110412) is formed on a part of the first semiconductor layer. The insulating film 110412 has a function of preventing the channel region of the transistor 110420 from being removed by etching. In other words, the insulating film 110412 functions as a channel protective film (channel stop film). Note that the third insulating film can be a single layer such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film (SiOxNy), or a stack of these films.

A second semiconductor layer (semiconductor layer 110) is formed on a part of the first semiconductor layer and a part of the third insulating film.
The semiconductor layer 110407 includes a portion that functions as one of a source electrode and a drain electrode. The semiconductor layer 110408 includes
The second conductor layer includes a portion that functions as the other of the source electrode and the drain electrode. The second conductor layer may be made of silicon or the like containing phosphorus or the like.

A second conductive layer (a conductive layer 110409, a conductive layer 110410, and a conductive layer 110411) is formed over the second semiconductor layer.
The conductive layer 110410 includes a portion that functions as one of a source electrode and a drain electrode.
The conductive layer 110412 includes a portion that functions as the other of the source and drain electrodes of the transistor 110420. The conductive layer 110412 includes a portion that functions as a second electrode of the capacitor 110421. The second conductive layer may be formed of any of Ti, Mo, Ta, Cr, W, Al, Nd, Cu, Ag, and A.
For example, U, Pt, NC, Si, Zn, Fe, Ca, Ge, or alloys thereof can be used. Alternatively, a laminate of these elements (including alloys) can be used.

Note that various insulating films or various conductive films may be formed as a step after the second conductive layer is formed.

Here, an example of a process that characterizes a channel protective transistor will be described. The first semiconductor layer, the second semiconductor layer, and the second conductive layer can be formed using the same mask.
At the same time, a channel region can be formed. Specifically, a first semiconductor layer is formed,
Next, a third insulating film (channel protection film, channel stop film) is formed using a mask, and then a second semiconductor layer and a second conductive layer are successively formed. Then, after the second conductive layer is formed, the first semiconductor layer, the second semiconductor layer, and the second conductive layer are formed using the same mask. However, the first semiconductor layer below the third insulating film is not removed by etching because it is protected by the third insulating film. This portion (the first semiconductor layer having the third insulating film at the top) is removed by etching.
The portion on which the insulating film is formed becomes the channel region.

Next, an example will be described in which a semiconductor substrate is used as a substrate for manufacturing transistors. Transistors manufactured using a semiconductor substrate have high mobility, and therefore the transistor size can be made smaller. As a result, the number of transistors per unit area can be increased (integration level can be increased), and for the same circuit configuration, the substrate size can be made smaller as the integration level increases, and therefore manufacturing costs can be reduced. Furthermore, for the same substrate size, the circuit scale can be made larger as the integration level increases, and therefore it is possible to provide higher functionality while keeping manufacturing costs roughly the same. Furthermore, there is little variation in characteristics,
The manufacturing yield can be increased. Furthermore, the operating voltage is small, so power consumption can be reduced. Furthermore, the mobility is high, so high-speed operation is possible.

A circuit formed by integrating transistors manufactured using a semiconductor substrate can be mounted on a device in the form of an IC chip or the like, thereby providing the device with various functions. For example, by integrating transistors manufactured using a semiconductor substrate to configure a peripheral driving circuit (data driver (source driver), scan driver (gate driver), timing controller, image processing circuit, interface circuit, power supply circuit, oscillation circuit, etc.) of a display device, a peripheral driving circuit that is small in size, consumes little power, and can operate at high speed can be manufactured at low cost and with high yield. Note that a circuit formed by integrating transistors manufactured using a semiconductor substrate may have transistors of a single polarity. This simplifies the manufacturing process, thereby reducing manufacturing costs.

Other examples of circuits that are constructed by integrating transistors manufactured using a semiconductor substrate include:
For example, it can be used in a display panel.
The display panel can be used for reflective liquid crystal panels such as CMOS (Crystal On Silicon), DMD (Digital Micromirror Device) elements with integrated micromirrors, EL panels, etc. By manufacturing these display panels using a semiconductor substrate, it is possible to manufacture display panels that are small in size, consume little power, and can operate at high speed at low cost and with high yield. Note that the display panel also includes those formed on elements that have functions other than driving the display panel, such as large-scale integrated circuits (LSIs).

Below, we will describe a method for manufacturing transistors using a semiconductor substrate.

First, regions 110604 and 110606 (hereinafter also referred to as regions 110604 and 110606) in which elements are isolated are formed on a semiconductor substrate 110600 (see FIG. 56A).
In this embodiment, a single crystal Si substrate having n-type conductivity is used as the semiconductor substrate 110600, and the semiconductor substrate 1106 is separated by a field oxide film 10602.
11 shows an example in which a p-well 110607 is provided in the 00 region 110606.

The substrate 110600 can be any semiconductor substrate, and is not particularly limited to this. For example, a single crystal Si substrate having n-type or p-type conductivity, a compound semiconductor substrate (GaAs substrate, I
nP substrate, GaN substrate, SiC substrate, sapphire substrate, ZnSe substrate, etc.), bonding method or SIMOX (Separation by Implanted Oxygen)
For example, a silicon on insulator (SOI) substrate manufactured using a method can be used.

The element isolation regions 110604 and 110606 are formed by a local oxidation of silicon (LOCOS) method.
Oxidation of Silicon (OS) method, trench isolation method, or the like can be used as appropriate.

The p-well formed in the region 110606 of the semiconductor substrate 110600 is
It can be formed by selectively introducing an impurity element having p-type conductivity into 0600. As the impurity element exhibiting p-type conductivity, boron (B), aluminum (Al), gallium (Ga), or the like can be used.

In this embodiment, since a semiconductor substrate having n-type conductivity is used as the semiconductor substrate 110600, no impurity element is introduced into the region 110604. However, an n-well may be formed in the region 110604 by introducing an impurity element exhibiting n-type conductivity. As the impurity element exhibiting n-type conductivity, phosphorus (P), arsenic (As), or the like can be used.
When a semiconductor substrate having p-type conductivity is used, an n-well may be formed by introducing an impurity element exhibiting n-type conductivity into region 110604, and no impurity element may be introduced into region 110606.

Next, insulating films 110632 and 11063 are formed to cover the regions 110604 and 110606.
4 are formed respectively (see FIG. 56(B)).

The insulating films 110632 and 110634 are, for example, subjected to a heat treatment to remove the insulating film 110632 from the semiconductor substrate 110600.
The insulating films 110632 and 110634 can be formed of silicon oxide films by oxidizing the surfaces of the regions 110604 and 110606 provided in the insulating film 110632 and 110634. After forming a silicon oxide film by thermal oxidation, the surface of the silicon oxide film can be nitrided by nitriding to form a laminated structure of a silicon oxide film and a film containing oxygen and nitrogen (silicon oxynitride film).

Alternatively, as described above, the insulating films 110632 and 110634 may be formed by using plasma processing.
The surface of the insulating film 110632 and 110634 is formed of a silicon oxide (SiOx) film or a silicon nitride (SiNx
As another example, the region 110604 can be formed by high-density plasma treatment.
After performing oxidation treatment on the surfaces of the regions 110604 and 110606, a nitridation treatment may be performed again by performing high density plasma treatment. In this case, a silicon oxide film is formed in contact with the surfaces of the regions 110604 and 110606, and a silicon oxynitride film is formed on the silicon oxide film, and the insulating film 110
The regions 110604 and 110606 are layers of a silicon oxide film and a silicon oxynitride film. As another example, a silicon oxide film may be formed on the surfaces of the regions 110604 and 110606 by thermal oxidation, and then an oxidation treatment or nitridation treatment may be performed by high density plasma treatment.

An insulating film 1106 formed in regions 110604 and 110606 of a semiconductor substrate 110600
32, 110634 will function as a gate insulating film in the completed transistor later.

Next, insulating films 110632 and 11063 formed in the regions 110604 and 110606 are
A conductive film is formed so as to cover 4 (see FIG. 56C). Here, an example is shown in which a conductive film 110636 and a conductive film 110638 are stacked in this order as the conductive film. Of course, the conductive film may be formed to have a single layer structure or a stacked structure of three or more layers.

The conductive films 110636 and 110638 are made of tantalum (Ta) or tungsten (W).
, titanium (Ti), molybdenum (Mo), aluminum (Al), copper (Cu), chromium (
The insulating layer 11 can be formed of an element selected from the group consisting of Cr, niobium (Nb), etc., or an alloy or compound material mainly composed of these elements. Alternatively, the insulating layer 11 can be formed of a metal nitride film obtained by nitriding these elements. In addition, the insulating layer 11 can be formed of a semiconductor material represented by polycrystalline silicon doped with an impurity element such as phosphorus, or a silicide doped with a metal material.

Here, tantalum nitride is used as the conductive film 110636, and the conductive film 11063
The conductive film 110636 may have a layered structure using tungsten.
A single layer or a stacked film selected from tungsten nitride, molybdenum nitride, or titanium nitride can be used. The conductive film 110638 can be a single layer or a stacked film selected from tantalum, molybdenum, or titanium.

Next, the laminated conductive films 110636 and 110638 are selectively etched and removed, so that the conductive film 110636 is formed in a part of the regions 110604 and 110606.
, 110638 are left to form gate electrodes 110640, 110642, respectively (see Figure 57(A)).

Next, a resist mask 110648 is selectively formed to cover the region 110604,
The resist mask 110648 and the gate electrode 110642 are used as a mask to form a region 1106
An impurity region 110652 is formed by introducing an impurity element into the semiconductor substrate 110652 (FIG. 57(
B)). As the impurity element, an impurity element imparting n-type or an impurity element imparting p-type is used. As the impurity element showing n-type, phosphorus (P), arsenic (As), etc. can be used. As the impurity element showing p-type, boron (B), aluminum (Al), gallium (Ga), etc. can be used. Here, phosphorus (P) is used as the impurity element. After the impurity element is introduced, heat treatment may be performed to diffuse the impurity element and repair the crystal structure.

In FIG. 57B, an impurity element is introduced into the region 110606 to form an impurity region 110652 which forms a source or drain region and a channel forming region 11065.
0 is formed.

Next, a resist mask 110666 is selectively formed to cover the region 110606,
The resist mask 110666 and the gate electrode 110640 are used as a mask to form a region 1106
An impurity region 110670 is formed by introducing an impurity element into 04 (FIG. 57(
57C). As the impurity element, an impurity element imparting n-type conductivity or an impurity element imparting p-type conductivity is used. As the impurity element imparting n-type conductivity, phosphorus (P), arsenic (As), or the like can be used. As the impurity element imparting p-type conductivity, boron (B), aluminum (Al), gallium (Ga), or the like can be used. Here, an impurity element (e.g., boron (B)) having a conductivity type different from that of the impurity element introduced into the region 110606 in FIG. 57C is introduced. As a result, an impurity region 11 forming a source or drain region is formed in the region 110604.
0670 and a channel formation region 110668 are formed. After the impurity element is introduced, heat treatment may be performed to diffuse the impurity element and repair the crystal structure.

Next, a second insulating film 110672 is formed so as to cover the insulating films 110632 and 110634 and the gate electrodes 110640 and 110642.
A wiring 110674 is formed that electrically connects to the impurity regions 110652 and 110670 formed in the semiconductor substrate 110606, respectively (see FIG. 57D).

The second insulating film 110672 is formed of silicon oxide (SiOx) by a CVD method, a sputtering method, or the like.
, silicon nitride (SiNx), silicon oxynitride (SiOxNy) (x>y), silicon oxynitride (S
The insulating film may be a single layer or a multilayer structure made of an insulating film containing oxygen or nitrogen such as iNxOy (x>y), a film containing carbon such as diamond-like carbon (DLC), an organic material such as epoxy, polyimide, polyamide, polyvinylphenol, benzocyclobutene, or acrylic, or a siloxane material such as a siloxane resin.
It corresponds to a material containing i-O-Si bonds. Siloxane is a compound consisting of silicon (Si) and oxygen (O).
The skeleton structure is formed by bonding with the above. As the substituent, an organic group containing at least hydrogen (e.g., an alkyl group, an aromatic hydrocarbon) is used. As the substituent, a fluoro group can also be used. Alternatively, as the substituent, an organic group containing at least hydrogen and a fluoro group can be used.

The wiring 110674 is formed of aluminum (Al) by a CVD method, a sputtering method, or the like.
Tungsten (W), titanium (Ti), tantalum (Ta), molybdenum (Mo), nickel (Ni), platinum (Pt), copper (Cu), gold (Au), silver (Ag), manganese (Mn),
The wiring 110674 is formed of an element selected from neodymium (Nd), carbon (C), and silicon (Si), or an alloy material or compound material mainly composed of these elements, in a single layer or multilayer. An alloy material mainly composed of aluminum corresponds to, for example, a material mainly composed of aluminum and containing nickel, or an alloy material mainly composed of aluminum and containing nickel and either or both of carbon and silicon. The wiring 110674 is formed of, for example, a barrier film and an aluminum silicon (
Layer structure of a barrier film and an aluminum silicon (Al-Si) film, and a barrier film and an aluminum silicon (Al-Si) film
It is preferable to adopt a laminated structure of a titanium nitride (TiN) film and a barrier film. The barrier film corresponds to a thin film made of titanium, titanium nitride, molybdenum, or molybdenum nitride. Aluminum and aluminum silicon have low resistance and are inexpensive, so they can be used for the wiring 11.
It is the best material for forming 0674. For example, if an upper and lower barrier layer are provided,
It is possible to prevent the occurrence of hillocks of aluminum or aluminum silicon. For example, when a barrier film made of titanium, which is a highly reducing element, is formed, even if a thin native oxide film is formed on the crystalline semiconductor film, this native oxide film is reduced. As a result, the wiring 1106
74 can be well connected electrically and physically to the crystalline semiconductor film.

It should be noted that the structure of the transistor is not limited to the structure shown in the figure. For example, the transistor may have an inverted staggered structure, a FinFET structure, or the like. The FinFET structure is preferable because it can suppress the short channel effect that accompanies miniaturization of the transistor size.

Next, another example in which a semiconductor substrate is used as a substrate for manufacturing a transistor will be described.

First, an insulating film is formed on a substrate 110800. Here, single crystal Si having n-type conductivity is used as the substrate 110800, and an insulating film 110802 and an insulating film 110804 are formed on the substrate 110800 (see FIG. 58A). For example, silicon oxide (SiOx) is formed as the insulating film 110802 by performing heat treatment on the substrate 110800.
A silicon nitride (SiNx) film is formed by using a VD method or the like.

The substrate 110800 can be any semiconductor substrate, without any particular limitations. For example, a single crystal Si substrate having n-type or p-type conductivity, a compound semiconductor substrate (GaAs substrate, I
nP substrate, GaN substrate, SiC substrate, sapphire substrate, ZnSe substrate, etc.), bonding method or SIMOX (Separation by IMplanted OXygen)
For example, a silicon on insulator (SOI) substrate manufactured using a method can be used.

The insulating film 110804 may be provided by forming the insulating film 110802 and then nitriding the insulating film 110802 by high density plasma treatment.
It may have a laminated structure of more than one layer.

Next, a resist mask 110806 is selectively patterned, and selective etching is performed using the resist mask 110806 as a mask, thereby forming a substrate 110800.
A recess 110808 is selectively formed in the insulating film 110802 (see FIG. 58B). The substrate 110800 and the insulating films 110802 and 110804 can be etched by dry etching using plasma.

Next, after removing the pattern of the resist mask 110806, an insulating film 110810 is formed so as to fill the recess 110808 formed in the substrate 110800 (FIG. 58(C)
reference).

The insulating film 110810 is formed by depositing silicon oxide, silicon nitride, silicon oxynitride (SiOxNy) (x>y>0), silicon nitride oxide (Si
The insulating film 11081 is formed using an insulating material such as NxOy (x>y>0).
As the film thickness 0, a silicon oxide film is formed by atmospheric pressure CVD or low pressure CVD using TEOS (tetraethyl orthosilicate) gas.

Next, grinding, polishing or CMP (Chemical Mechanical Polishing) is performed.
By performing a polishing process, the surface of the substrate 110800 is exposed. Then, the surface of the substrate 110800 is divided by the insulating film 110810 formed in the recess 110808 of the substrate 110800 (see FIG. 59A). Here, the divided regions are referred to as regions 110812 and 110813. Note that the insulating film 110811 is obtained by removing a part of the insulating film 110810 by a grinding process, a polishing process, or a CMP process.

Next, an impurity element having a p-type conductivity is selectively introduced to the substrate 11.
A p-well 110815 is formed in a region 110813 of 0800. As an impurity element exhibiting a p-type, boron (B), aluminum (Al), gallium (Ga), or the like can be used. Here, boron (B) is introduced as the impurity element into the region 110813. After the impurity element is introduced, a heat treatment may be performed to diffuse the impurity element and repair the crystal structure.

In addition, when a semiconductor substrate having an n-type conductivity is used as the substrate 110800, the region 1
Although it is not necessary to introduce an impurity element into 10812, an n-well may be formed in the region 110812 by introducing an impurity element that exhibits n-type conductivity. As the impurity element that exhibits n-type conductivity, phosphorus (P), arsenic (As), or the like can be used.

On the other hand, when a semiconductor substrate having p-type conductivity is used, an n-well may be formed by introducing an impurity element exhibiting n-type conductivity into region 110812, and no impurity element may be introduced into regions 110812 and 110813.

Next, an insulating film 11083 is formed on the surface of the regions 110812 and 110813 of the substrate 110800.
2, 110834 are formed respectively (see FIG. 59(B)).

The insulating films 110832 and 110834 can be formed of silicon oxide films by, for example, performing heat treatment to oxidize the surfaces of the regions 110812 and 110813 provided on the substrate 110800. Alternatively, a silicon oxide film may be formed by thermal oxidation, and then a nitriding treatment is performed to nitride the surface of the silicon oxide film, thereby forming a laminated structure of a silicon oxide film and a film containing oxygen and nitrogen (silicon oxynitride film).

Alternatively, as described above, the insulating films 110832 and 110834 may be formed by plasma treatment.
The surface of the insulating film 13 is oxidized or nitrided by high density plasma treatment.
As another example, the regions 110812 and 110834 can be formed of a silicon oxide (SiOx) film or a silicon nitride (SiNx) film by high density plasma treatment.
After performing oxidation treatment on the surface of the insulating film 110813, a high-density plasma treatment may be performed again to perform nitridation treatment. In this case, a silicon oxide film is formed in contact with the surfaces of the regions 110812 and 110813, and a silicon oxynitride film is formed on the silicon oxide film.
As another example, a silicon oxide film and a silicon oxynitride film may be laminated on the surfaces of the regions 110812 and 110834 by a thermal oxidation method, and then an oxidation treatment or a nitridation treatment may be performed by a high density plasma treatment.

In addition, the insulating film 110 formed in the regions 110812 and 110813 of the substrate 110800
832, 110834 will function as gate insulating films in the transistors that will be completed later.

Next, a conductive film is formed to cover insulating films 110832 and 110834 formed in regions 110812 and 110813 provided on the substrate 110800 (see FIG. 59C).
Here, an example is shown in which the conductive film is formed by sequentially stacking a conductive film 110836 and a conductive film 110838. Of course, the conductive film may be formed to have a single layer structure or a stacked structure of three or more layers.

The conductive films 110836 and 110838 are made of tantalum (Ta) or tungsten (W).
, titanium (Ti), molybdenum (Mo), aluminum (Al), copper (Cu), chromium (
The insulating layer 11 can be formed of an element selected from the group consisting of Cr, niobium (Nb), etc., or an alloy or compound material mainly composed of these elements. Alternatively, the insulating layer 11 can be formed of a metal nitride film obtained by nitriding these elements. In addition, the insulating layer 11 can be formed of a semiconductor material represented by polycrystalline silicon doped with an impurity element such as phosphorus, or a silicide doped with a metal material.

Here, tantalum nitride is used as the conductive film 110836, and the conductive film 110838
Alternatively, the conductive film 110836 can be a single layer or a stacked film selected from tantalum nitride, tungsten nitride, molybdenum nitride, or titanium nitride. The conductive film 110838 can be a single layer or a stacked film selected from tungsten, tantalum, molybdenum, or titanium.

Next, the conductive films 110836 and 110838 that are stacked are selectively etched and removed, so that the conductive films 110836 and 110838 remain in parts of the regions 110812 and 110813 of the substrate 110800, and conductive films 110840 and 110842 that function as gate electrodes, respectively, are formed (see FIG. 59D).
In areas not overlapping with 0840 and 110842, the surface of substrate 110800 is exposed.

Specifically, in the region 110812 of the substrate 110800, a portion of the insulating film 110832 that does not overlap with the conductive film 110840 is selectively removed so that the ends of the conductive film 110840 and the insulating film 110832 are approximately aligned with each other.
In the insulating film 110813, a portion of the insulating film 110834 that does not overlap with the conductive film 110842 is selectively removed, and the conductive film 110842 and the insulating film 110834 are formed so that their ends roughly coincide with each other.

In this case, the insulating films, etc. in the non-overlapping portions may be removed simultaneously with the formation of the conductive films 110840 and 110842, or the insulating films, etc. in the non-overlapping portions may be removed using a resist mask remaining after the formation of the conductive films 110840 and 110842 or the conductive films 110840 and 110842 as a mask.

Next, an impurity element is selectively introduced into regions 110812 and 110813 of the substrate 110800 (see FIG. 60A). Here, a low concentration impurity element that imparts n-type conductivity is selectively introduced into the region 110813 using the conductive film 110842 as a mask, and a low concentration impurity element that imparts p-type conductivity is selectively introduced into the region 110812 using the conductive film 110840 as a mask.
As the impurity element that imparts n-type conductivity, phosphorus (P), arsenic (As), etc. can be used. As the impurity element that imparts p-type conductivity, boron (B), aluminum (Al), gallium (Ga), etc. can be used. After the impurity element is introduced, a heat treatment may be performed to diffuse the impurity element and repair the crystal structure.

Next, a sidewall 110854 in contact with the side surfaces of the conductive films 110840 and 110842 is
Specifically, a film containing an inorganic material such as silicon, silicon oxide, or silicon nitride, or a film containing an organic material such as an organic resin is formed as a single layer or a laminate by plasma CVD, sputtering, or the like. Then, the insulating film is selectively etched by anisotropic etching mainly in the vertical direction, so that the insulating film can be formed so as to be in contact with the side surfaces of the conductive films 110840 and 110842. Note that the sidewall 110854 is an LDD (Light Drain) insulating film.
The sidewall 110854 is used as a doping mask when forming a ly doped drain region. Here, the sidewall 110854 is formed so as to be in contact with the insulating film formed below the conductive films 110840 and 110842 and the side surfaces of the floating gate electrode.

Next, impurity elements are introduced into regions 110812 and 110813 of the substrate 110800 using the sidewalls 110854 and the conductive films 110840 and 110842 as masks to form impurity regions that function as source or drain regions (FIG. 60(B)
)). Here, a sidewall 11085 is formed on a region 110813 of a substrate 110800.
An impurity element that imparts a high concentration of n-type is introduced into region 110812 using sidewall 110854 and conductive film 110840 as a mask. An impurity element that imparts a high concentration of p-type is introduced into region 110812 using sidewall 110854 and conductive film 110840 as a mask.

As a result, an impurity region 110858 forming a source or drain region, a low concentration impurity region 110860 forming an LDD region, and a channel formation region 110856 are formed in the region 110812 of the substrate 110800.
In the region 813, an impurity region 110864 forming a source or drain region, a low concentration impurity region 110866 forming an LDD region, and a channel formation region 110862 are formed.

Here, an example in which the LDD region is formed using a sidewall is shown, but the present invention is not limited to this. The LDD region may be formed using a mask or the like without using a sidewall, or the LDD region may not be formed. When the LDD region is not formed, the manufacturing process can be simplified, and therefore the manufacturing cost can be reduced.

In this case, the conductive films 110840 and 110842 are not overlapped with the substrate 1.
The impurity element is introduced while the surface of the substrate 11 is exposed.
The channel formation regions 11 are formed in the regions 110812 and 110813 of the 0800.
0856 and 110862 can be formed in a self-aligned manner using conductive films 110840 and 110842.

Next, a second insulating film 110877 is formed so as to cover the insulating films, conductive films, etc. provided in regions 110812 and 110813 of the substrate 110800, and an opening 110878 is formed in the insulating film 110877 (see Figure 60C).

The second insulating film 110877 is formed of silicon oxide (SiOx) by a CVD method, a sputtering method, or the like.
, silicon nitride (SiNx), silicon oxynitride (SiOxNy) (x>y), silicon oxynitride (S
The insulating film may be a single layer or a multilayer structure made of an insulating film containing oxygen or nitrogen such as iNxOy (x>y), a film containing carbon such as diamond-like carbon (DLC), an organic material such as epoxy, polyimide, polyamide, polyvinylphenol, benzocyclobutene, or acrylic, or a siloxane material such as a siloxane resin.
It corresponds to a material containing i-O-Si bonds. Siloxane is a compound consisting of silicon (Si) and oxygen (O).
The skeleton structure is formed by bonding with the above. As the substituent, an organic group containing at least hydrogen (e.g., an alkyl group, an aromatic hydrocarbon) is used. As the substituent, a fluoro group can also be used. Alternatively, as the substituent, an organic group containing at least hydrogen and a fluoro group can be used.

Next, a conductive film 110880 is formed in the opening 110878 by a CVD method, and a conductive film 110882a is formed on the insulating film 110877 so as to be electrically connected to the conductive film 110880.
110882d are selectively formed (see FIG. 60(D)).

The conductive films 110880 and 110882a to 110882d are formed by a CVD method, a sputtering method, or the like using aluminum (Al), tungsten (W), titanium (Ti), tantalum (
Ta), molybdenum (Mo), nickel (Ni), platinum (Pt), copper (Cu), gold (Au
), silver (Ag), manganese (Mn), neodymium (Nd), carbon (C), silicon (Si
The conductive film 110 is formed of an element selected from the group consisting of aluminum, nickel, and either one or both of carbon and silicon. ....
882a to 882d are, for example, a barrier film and aluminum silicon (Al-Si)
It is preferable to adopt a laminated structure of a film and a barrier film, or a laminated structure of a barrier film, an aluminum silicon (Al-Si) film, a titanium nitride (TiN) film and a barrier film.
It corresponds to a thin film made of titanium nitride, molybdenum, or molybdenum nitride. Aluminum and aluminum silicon have low resistance and are inexpensive, making them ideal materials for forming the conductive film 110880. For example, by providing upper and lower barrier layers, the occurrence of hillocks in aluminum or aluminum silicon can be prevented. For example, by forming a barrier film made of titanium, which is a highly reducing element, even if a thin natural oxide film is formed on the crystalline semiconductor film, this natural oxide film can be reduced and good contact can be made with the crystalline semiconductor film. Here, the conductive film 110880 is formed by CVD using tungsten (W
) can be formed by selectively growing the

Through the above steps, a p-type transistor formed in region 110812 of substrate 110800 and an n-type transistor formed in region 110813 can be obtained.

It should be noted that the structure of the transistor constituting the transistor of the present invention is not limited to the structure shown in the figure. For example, the transistor may have an inverted staggered structure, a FinFET structure, or other structure. The FinFET structure is preferable because it can suppress the short channel effect that accompanies miniaturization of the transistor size.

The structure of a transistor and a method for manufacturing a transistor have been described above.
Wiring, electrodes, conductive layers, conductive films, terminals, vias, plugs, etc. are made of aluminum (Al), tantalum (Ta), titanium (Ti), molybdenum (Mo), tungsten (W), neodymium (Nd), chromium (Cr), nickel (Ni), platinum (Pt), gold (Au), and silver (Ag).
, Copper (Cu), Magnesium (Mg), Scandium (Sc), Cobalt (C
o), zinc (Zn), niobium (Nb), silicon (Si), phosphorus (P), boron (B), arsenic (As), gallium (Ga), indium (In), tin (Sn
), oxygen (O), or a compound or alloy material containing one or more elements selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), indium tin oxide containing silicon oxide (ITSO), zinc oxide (ZnO), tin oxide (SnO), cadmium tin oxide (CTO
), aluminum neodymium (Al-Nd), magnesium silver (Mg-Ag), molybdenum niobium (Mo-Nb), etc. Alternatively, wiring, electrodes, conductive layers, conductive films, terminals, etc. are preferably formed of a material that combines these compounds. Alternatively, a compound (silicide) of one or more elements selected from the above group and silicon (e.g., aluminum silicon, molybdenum silicon, nickel silicide, etc.).
It is preferable that the insulating layer is formed of one or more elements selected from the above group and a compound of nitrogen (eg, titanium nitride, tantalum nitride, molybdenum nitride, etc.).

Silicon (Si) may contain n-type impurities (such as phosphorus) or p-type impurities (such as boron). Silicon containing impurities improves its electrical conductivity and allows it to behave like a normal conductor. This makes it easier to use it as wiring, electrodes, etc.

Silicon having various crystallinity, such as single crystal, polycrystalline (polysilicon), and microcrystalline (microcrystal silicon), can be used. Alternatively, silicon having no crystallinity, such as amorphous silicon, can be used. By using single crystal silicon or polycrystalline silicon, wiring, electrodes, conductive layers,
It is possible to reduce the resistance of conductive films, terminals, etc. By using amorphous silicon or microcrystalline silicon, wiring and the like can be formed in a simple process.

Aluminum and silver have high electrical conductivity, which can reduce signal delay. Furthermore, they are easy to etch, which makes them easy to pattern and allows fine processing.

Copper has a high electrical conductivity and can therefore reduce signal delay. When using copper, it is desirable to use a laminated structure in order to improve adhesion.

Molybdenum or titanium is preferable because it has advantages such as not causing defects even when in contact with an oxide semiconductor (ITO, IZO, etc.) or silicon, being easy to etch, and having high heat resistance.

Tungsten is preferable because it has advantages such as high heat resistance.

Neodymium is desirable because it has the advantage of being highly heat resistant. In particular, when neodymium is alloyed with aluminum, the heat resistance is improved and aluminum is less likely to develop hillocks.

Silicon is preferable because it has advantages such as being able to be formed simultaneously with a semiconductor layer of a transistor and having high heat resistance.

In addition, ITO, IZO, ITSO, zinc oxide (ZnO), silicon (Si), tin oxide (S
Since cadmium tin oxide (CTO) and cadmium tin oxide (CTO) are transparent, they can be used in light transmitting portions, for example, as pixel electrodes and common electrodes.

IZO is preferable because it is easy to etch and process. When IZO is etched, it is unlikely that residues will remain. Therefore, when IZO is used as a pixel electrode, it is possible to reduce problems (such as short circuits and alignment disorders) in liquid crystal elements and light-emitting elements.

In addition, wiring, electrodes, conductive layers, conductive films, terminals, vias, plugs, etc. may have a single-layer structure.
It may have a multi-layer structure. By making it a single-layer structure, the manufacturing process of wiring, electrodes, conductive layers, conductive films, terminals, etc. can be simplified, the number of process days can be reduced, and costs can be reduced. Alternatively, by making it a multi-layer structure, it is possible to form wiring, electrodes, etc. with good performance by taking advantage of the advantages of each material while reducing its disadvantages.
For example, by including a low-resistance material (such as aluminum) in the multi-layer structure, it is possible to reduce the resistance of the wiring. As another example, by sandwiching a low-heat-resistant material between high-heat-resistant materials in a multi-layer structure, it is possible to increase the heat resistance of wiring, electrodes, etc. while taking advantage of the advantages of the low-heat-resistant material. For example, it is desirable to have a multi-layer structure in which a layer containing aluminum is sandwiched between layers containing molybdenum, titanium, neodymium, etc.

Here, when wiring, electrodes, etc. are in direct contact with each other, they may have a negative effect on each other. For example, one wiring, electrode, etc. may penetrate into the material of the other wiring, electrode, etc., changing the properties and making it impossible to achieve the original purpose. As another example, when forming or manufacturing a high resistance part, a problem may occur and it may not be possible to manufacture it normally. In such a case, it is advisable to sandwich or cover a material that is easily reactive due to the laminated structure with a material that is less likely to react. For example, when connecting ITO and aluminum, it is desirable to sandwich titanium, molybdenum, or neodymium alloy between ITO and aluminum. As another example, when connecting silicon and aluminum, it is desirable to sandwich titanium, molybdenum, or neodymium alloy between ITO and aluminum.

The term "wiring" refers to an arrangement of conductors. The wiring may extend linearly or may be arranged short and not extend. Therefore, electrodes are included in the wiring.

Carbon nanotubes may be used as wiring, electrodes, conductive layers, conductive films, terminals, vias, plugs, etc. Furthermore, carbon nanotubes have translucency and can be used in light transmitting portions, for example, as pixel electrodes and common electrodes.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 4)
In this embodiment, a configuration of a display device will be described.

The structure of the display device will be described with reference to Fig. 61A, which is a top view of the display device.

Pixel portion 170101, scanning line side input terminal 170103, and signal line side input terminal 170104
are formed on a substrate 170100, scanning lines are formed on the substrate 170100 extending in the row direction from a scanning line side input terminal 170103, and signal lines are formed on the substrate 170100 extending in the column direction from a signal line side input terminal 170104. Then, pixels 170102 are arranged in a matrix at the intersections of the scanning lines and signal lines in a pixel portion 170101.

The scanning line side input terminals 170103 are formed on both sides of the substrate 170100 in the row direction.
The scanning lines extending from one of the scanning line side input terminals 170103 and the scanning lines extending from the other scanning line side input terminal 170103 are alternately formed.
Since the scanning line side input terminals 170102 can be arranged at high density, a high-definition display device can be obtained. However, the present invention is not limited to this, and the scanning line side input terminals 170103 may be formed only on one side in the row direction of the substrate 170100. In this case, the frame of the display device can be made smaller. The area of the pixel portion 170101 can be enlarged. As another example, a scanning line extending from one scanning line side input terminal 170103 and a scanning line extending from the other scanning line side input terminal 170103 can be formed on the other scanning line side input terminal 170103.
The scanning line extending from the input terminal 170103 may be common to the scanning line. In this case, it is suitable for a display device with a large load on the scanning line, such as a large display device. Note that a signal is input to the scanning line from an external driving circuit via the scanning line side input terminal 170103.

The signal line side input terminal 170104 is formed on one side of the substrate 170100 in the column direction.
In this case, the frame of the display device can be made smaller. The area of the pixel portion 170101 can be expanded. However, this is not limited thereto, and the signal line side input terminals 170104 may be formed on both sides of the substrate 170100 in the column direction. In this case, the pixels 170102 can be arranged at high density. Note that, when a signal is input from an external driver circuit to the signal line side input terminals 1
The signal is input to the scanning line via 70104.

The pixel 170102 has a switching element and a pixel electrode. In each pixel 170102, a first terminal of the switching element is connected to a signal line, and a second terminal of the switching element is connected to the pixel electrode. The switching element is controlled to be turned on and off by a scanning line. However, this is not limited to this, and various configurations can be used.
For example, the pixel 170102 may have a capacitance element. In this case, the capacitance line is connected to the substrate 1
It is preferable to form the power supply line on the substrate 170100. As another example, the pixel 170102 may have a current source such as a driving transistor. In this case, it is preferable to form the power supply line on the substrate 170100.

The substrate 170100 may be a single crystal substrate, an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a paper substrate, a cellophane substrate, a stone substrate, a wood substrate, or a cloth substrate (natural fiber (silk,
cotton, hemp), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate, cupra, rayon, regenerated polyester), leather substrates, rubber substrates,
A stainless steel substrate, a substrate having stainless steel foil, etc. may be used. Alternatively, skin (skin epidermis, dermis) or subcutaneous tissue of an animal such as a human may be used as the substrate. However, the substrate is not limited to these, and various other substrates may be used.

In addition, as the switching element of the pixel 170102, a transistor (for example, a bipolar transistor, a MOS transistor, etc.), a diode (for example, a PN diode, a PIN diode, a Schottky diode, an MIM (Metal Insulator
r Metal) Diode, MIS (Metal Insulator Semiconductor)
A switching element such as a diode (inductor), a diode-connected transistor, a thyristor, etc., can be used. However, the present invention is not limited to this, and various other elements can be used. When a MOS transistor is used as the switching element of the pixel 170102, the gate electrode is connected to a scanning line, the first terminal is connected to a signal line, and the second terminal is connected to a pixel electrode.

So far, the case where signals are inputted by an external driving circuit has been described, but this is not limiting and an IC chip can be mounted on the display device.

For example, as shown in FIG. 62A, an IC chip 170201 can be mounted on a substrate 170100 by a COG (Chip on Glass) method.
Since the C chip 170201 can be inspected before being mounted on the substrate 170100, the yield of the display device can be improved. The reliability can be improved. Note that the same reference numerals are used for the components common to the configuration of FIG. 61A, and the description thereof will be omitted.

As another example, as shown in FIG. 62(B),
By using the mounting method, the IC chip 170201 is attached to the FPC (Flexible Printed Circuit)
In this case, the IC
Since the chip 170201 can be inspected before being mounted on the FPC 170200, the yield of the display device can be improved. The reliability can be improved. Note that the same reference numerals are used for the same components as those in the configuration of FIG. 61A, and the description thereof will be omitted.

Here, not only is an IC chip mounted on the substrate 170100, but a driving circuit is also mounted on the substrate 1701.
00.

For example, as shown in FIG. 61B, the scanning line driver circuit 170105 can be formed on the substrate 170100. In this case, the number of components can be reduced, thereby reducing costs. The number of connections with circuit components can be reduced, thereby improving reliability. Since the driving frequency of the scanning line driver circuit 170105 is low, the scanning line driver circuit 170105 can be easily formed by using amorphous silicon or microcrystalline silicon as the semiconductor layer of the transistor. An IC chip for outputting a signal to a signal line may be mounted on the substrate 170100 by the COG method. Alternatively, an FPC on which an IC chip for outputting a signal to a signal line is mounted by the TAB method may be disposed on the substrate 170100. The scanning line driver circuit 170105
An IC chip for controlling the scanning line driver circuit 170105 may be mounted on the substrate 170100 by the COG method. Alternatively, an IC chip for controlling the scanning line driver circuit 170105 may be mounted on the substrate 170100 by the TAB method.
The PC may be disposed on the substrate 170100. Note that the same reference numerals are used for the components common to the configuration of Figure 61 (A) and the description thereof will be omitted.

As another example, as shown in FIG. 61C, the scanning line driver circuit 170105 and the signal line driver circuit 170106 can be formed on the substrate 170100. This allows the number of components to be reduced, thereby reducing costs. The number of connections to the circuit components can be reduced, thereby improving reliability. An IC chip for controlling the scanning line driver circuit 170105 may be mounted on the substrate 170100 by a COG method. Alternatively, the scanning line driver circuit 170106 may be formed on the substrate 170100 by a COG method.
An FPC on which an IC chip for controlling 0105 is mounted by the TAB method is placed on the substrate 170100.
An IC chip for controlling the signal line driver circuit 170106 may be disposed on the substrate 170106.
61A. Alternatively, an FPC on which an IC chip for controlling the signal line driver circuit 170106 is mounted by a TAB method may be disposed on the substrate 170100. Note that common reference numerals are used to designate parts common to the configuration of FIG. 61A, and description thereof will be omitted.

Next, the configuration of another display device will be described with reference to Fig. 63. Specifically, the display device will be described which has a TFT substrate, a counter substrate, and a display layer sandwiched between the TFT substrate and the counter substrate. Fig. 63 is a top view of the display device.

A pixel portion 170301, a scanning line driver circuit 170302a, a scanning line driver circuit 170302b, and a signal line driver circuit 170303 are formed on a substrate 170300.
b and the signal line driver circuit 170303 are sealed to the substrate 170300 by a sealant 170321.
and substrate 170310.

Furthermore, an FPC 107320 is disposed on the substrate 170300. An IC chip 107321 is mounted on the FPC 170320 by the TAB method.

A plurality of pixels are arranged in a matrix in the pixel portion 170301. Scanning lines extend in the row direction from a scanning line driver circuit 170302a and are formed on the substrate 170300. Scanning lines extend in the row direction from a scanning line driver circuit 170302b and are formed on the substrate 170300. Signal lines extend in the column direction from a signal line driver circuit 170303 and are formed on the substrate 170300.
It is formed on 0300.

The scanning line driver circuit 170302a is formed on one side of the row direction of the substrate 170300, and the scanning line driver circuit 170302b is formed on the other side of the row direction of the substrate 170300. The scanning lines extending from the scanning line driver circuit 170302a and the scanning lines extending from the scanning line driver circuit 170302b are alternately formed. Therefore, a high-definition display device can be obtained. However, this is not limited to this, and only one of the scanning line driver circuit 170302a and the scanning line driver circuit 170302b may be formed on the substrate 170300. In this case, the frame of the display device can be made smaller. The area of the pixel portion 170301 can be enlarged. As another example, the scanning lines extending from the scanning line driver circuit 170302a and the scanning line driver circuit 170302b may be common. In this case, it is suitable for a display device with a large load on the scanning lines, such as a large display device.

The signal line driver circuit 170303 is formed on one side of the substrate 170300 in the column direction. This makes it possible to reduce the frame of the display device. This makes it possible to expand the area of the pixel portion 170301. However, this is not limited thereto.
Alternatively, the electrodes 302 may be formed on both sides of the pixel electrode 300 in the column direction. In this case, a high-definition display device can be obtained.

The substrate 170300 may be a single crystal substrate, an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a paper substrate, a cellophane substrate, a stone substrate, a wood substrate, or a cloth substrate (natural fiber (silk,
cotton, hemp), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate, cupra, rayon, regenerated polyester), leather substrates, rubber substrates,
A stainless steel substrate, a substrate having stainless steel foil, etc. may be used. Alternatively, skin (skin epidermis, dermis) or subcutaneous tissue of an animal such as a human may be used as the substrate. However, the substrate is not limited to these, and various other substrates may be used.

The switching elements included in the display device include transistors (e.g., bipolar transistors, MOS transistors, etc.), diodes (e.g., PN diodes, PIN
Diodes, Schottky diodes, MIM (Metal Insulator Me
tal) diode, MIS (Metal Insulator Semiconductor
A diode, a diode-connected transistor, a thyristor, etc., can be used. However, the present invention is not limited to these, and various other elements can be used.

So far, the case where the driver circuit is formed on the same substrate as the pixel portion has been described. However, this is not limiting, and a separate substrate on which a part or all of the driver circuit is formed may be mounted as an IC chip on the substrate on which the pixel portion is formed.

For example, as shown in FIG. 64A, an IC chip 170401 is used instead of the signal line driver circuit.
can be mounted on the substrate 170300 by the COG method. In this case, by mounting the IC chip 170401 on the substrate 170300 by the COG method instead of the signal line driver circuit, an increase in power consumption can be prevented. This is because the signal line driver circuit has a high driving frequency and therefore consumes a large amount of power. Since the IC chip 170401 can be inspected before being mounted on the substrate 170300, the yield of the display device can be improved. Reliability can be improved. Since the scanning line driver circuit 170302a and the scanning line driver circuit 170302b have a low driving frequency, the scanning line driver circuit 170302a and the scanning line driver circuit 170302b can be easily formed using amorphous silicon or microcrystalline silicon as the semiconductor layer of the transistor. Therefore, a display device can be manufactured using a large substrate. Note that common reference numerals are used for parts common to the configuration of FIG. 63, and their description will be omitted.

As another example, as shown in FIG. 64B, an IC chip 170 is used instead of the signal line driver circuit.
Alternatively, the IC chip 170401 may be mounted on the substrate 170300 by the COG method, the IC chip 170501a may be mounted on the substrate 170300 instead of the scanning line driver circuit 170302a by the COG method, and the IC chip 170501b may be mounted on the substrate 170300 instead of the scanning line driver circuit 170302b by the COG method. In this case, the IC chip 170401, the IC chip 170501a, and the IC chip 170501b can be inspected before being mounted on the substrate 170300, so that the yield of the display device can be improved. The reliability can be improved. The substrate 170300
Amorphous silicon or microcrystalline silicon can be easily used as a semiconductor layer of a transistor formed in the display device. Therefore, a display device can be manufactured using a large substrate. Note that the same reference numerals are used for the same components as those in the configuration of FIG. 63, and the description thereof will be omitted.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 5)
In this embodiment, the operation of the display device will be described.

Figure 65 shows an example of the configuration of a display device.

The display device 180100 includes a pixel portion 180101, a signal line driver circuit 180103, and a scanning line driver circuit 180104. In the pixel portion 180101, a plurality of signal lines S1 to Sm are arranged extending from the signal line driver circuit 180103 in the column direction.
In the pixel 180102, a plurality of scanning lines G1 to Gn are arranged extending in the row direction from a scanning line driving circuit 180104. Then, at the intersections of a plurality of signal lines S1 to Sm and a plurality of scanning lines G1 to Gn, pixels 180102 are arranged in a matrix.

The signal line driver circuit 180103 has a function of outputting signals to the signal lines S1 to Sn. These signals may be called video signals.
has a function of outputting signals to the scanning lines G1 to Gm. These signals may be called scanning signals.

Each pixel 180102 has at least a switching element connected to a signal line. The switching element is controlled to be turned on and off by the potential (scanning signal) of the scanning line. When the switching element is on, the pixel 180102 is selected, and when the switching element is off, the pixel 180102 is not selected.

When the pixel 180102 is selected (selected state), a video signal is input from a signal line to the pixel 180102. Then, the state of the pixel 180102 (e.g., luminance, transmittance, voltage of a storage capacitor, etc.) changes according to this input video signal.

When the pixel 180102 is not selected (deselected state), the video signal is
02. However, since the pixel 180102 holds a potential corresponding to the video signal input when selected, the pixel 180102 maintains a value corresponding to the video signal (for example, brightness, transmittance, voltage of a storage capacitor, etc.).

Note that the configuration of the display device is not limited to that shown in Fig. 65. For example, new wirings (scanning lines, signal lines, power supply lines, capacitance lines, common lines, and the like) may be added depending on the configuration of the pixel 180102. As another example, circuits having various functions may be added.

Figure 66 shows an example of a timing chart to explain the operation of a display device.

The timing chart in Fig. 66 shows one frame period, which corresponds to the period for displaying one screen's worth of image. There are no particular limitations on one frame period, but it is preferable that it be at least 1/60 seconds or less so that a person viewing the image does not perceive flicker.

The timing chart of FIG. 66 shows the first scanning line G1, the i-th scanning line Gi (scanning line G1
1 to Gm), the (i+1)th scanning line Gi+1, and the mth scanning line Gm are selected, respectively.

When a scanning line is selected, the pixel 180102 connected to the scanning line is also selected at the same time. For example, when the scanning line Gi in the i-th row is selected, the pixel 180102 connected to the scanning line Gi in the i-th row is also selected.

The scanning lines G1 to Gm are selected in order from the first scanning line G1 to the m-th scanning line Gm (hereinafter, also referred to as scanning). For example, during a period in which the i-th scanning line Gi is selected, the scanning lines other than the i-th scanning line Gi (G1 to Gi-1, Gi+1 to Gm) are selected.
) is not selected. Then, in the next period, the (i+1)th scanning line Gi+1 is selected. Note that the period during which one scanning line is selected is called one gate selection period.

Therefore, when a certain row of scan lines is selected, the pixels 180 connected to that row are
A video signal is input from each of the signal lines G1 to Gm to the input terminal 102. For example,
While the scanning line Gi of the i-th row is selected, a plurality of pixels 180102 connected to the scanning line Gi of the i-th row each receive an arbitrary video signal from each of the signal lines S1 to Sn.
In this way, each of the pixels 180102 can be independently controlled by scanning and video signals.

Next, a case where one gate selection period is divided into a plurality of sub-gate selection periods will be described.
FIG. 67 shows a timing chart in the case where one gate selection period is divided into two sub-gate selection periods (a first sub-gate selection period and a second sub-gate selection period).

In addition, one gate selection period can be divided into three or more sub-gate selection periods.

The timing chart in Fig. 67 shows one frame period, which corresponds to the period for displaying one screen's worth of image. There are no particular limitations on one frame period, but it is preferable that it be at least 1/60 seconds or less so that a person viewing the image does not perceive flicker.

One frame consists of two subframes (a first subframe and a second subframe).
It is divided into:

The timing chart of FIG. 67 shows the scanning line Gi in the i-th row, the scanning line Gi+1 in the i+1-th row,
13 shows the timings at which the scanning line Gj (one of the scanning lines Gi+1 to Gm), the j+1th scanning line, and the Gj+1th scanning line Gj+1 are selected.

When a scanning line is selected, the pixel 180102 connected to the scanning line is also selected at the same time. For example, when the scanning line Gi in the i-th row is selected, the pixel 180102 connected to the scanning line Gi in the i-th row is also selected.

The scanning lines G1 to Gm are scanned in sequence during each sub-gate selection period. For example, in one gate selection period, the scanning line Gi in the i-th row is selected during the first sub-gate selection period, and the scanning line Gj in the j-th row is selected during the second sub-gate selection period.
This makes it possible to operate as if scanning signals for two rows were selected simultaneously during one gate selection period. At this time, different video signals are input to the signal lines S1 to Sn during the first sub-gate selection period and the second sub-gate selection period. Therefore,
A plurality of pixels 180102 connected to the i-th row and a plurality of pixels 180103 connected to the j-th row
Separate video signals can be input to the 80102 and 80103.

Next, a driving method for converting the frame rate of input image data (also referred to as input frame rate) and the frame rate of display (also referred to as display frame rate) will be described. Note that the frame rate is the number of frames per second, and is expressed in Hz.

In this embodiment, the input frame rate does not necessarily have to match the display frame rate. If the input frame rate and the display frame rate are different, the frame rate can be converted by a circuit that converts the frame rate of the image data (a frame rate conversion circuit). In this way, even if the input frame rate and the display frame rate are different, display can be performed at various display frame rates.

When the input frame rate is higher than the display frame rate, a portion of the input image data is discarded, thereby enabling conversion to various display frame rates for display.
In this case, the display frame rate can be reduced, so that the operating frequency of the drive circuit for display can be reduced, and power consumption can be reduced. On the other hand, when the input frame rate is smaller than the display frame rate, various display frame rates can be converted and displayed by using means such as displaying all or part of the input image data multiple times, generating a different image from the input image data, or generating an image unrelated to the input image data. In this case, the quality of the moving image can be improved by increasing the display frame rate.

In this embodiment, a frame rate conversion method when the input frame rate is smaller than the display frame rate will be described in detail. The frame rate conversion method when the input frame rate is larger than the display frame rate can be realized by performing the reverse procedure of the frame rate conversion method when the input frame rate is smaller than the display frame rate.

In this embodiment, an image displayed at the same frame rate as the input frame rate is referred to as a basic image. On the other hand, an image displayed at a frame rate different from the basic image, which is displayed to match the input frame rate and the display frame rate, is referred to as an interpolated image. The same image as the input image data can be used as the basic image. The same image as the basic image can be used as the interpolated image. Furthermore, an image different from the basic image can be created, and the created image can be used as the interpolated image.

When creating an interpolated image, there are several methods: detecting the change over time (image movement) of the input image data and using an intermediate image between these as the interpolated image; multiplying the luminance of the base image by a certain coefficient as the interpolated image; creating multiple different images from the input image data and presenting the multiple images in succession over time (one of the multiple images is used as the base image,
A method of generating a plurality of different images from input image data by converting the gamma value of the input image data, dividing the gradation values contained in the input image data, etc., is a method of generating a plurality of different images from the input image data by converting the gamma value of the input image data, dividing the gradation values contained in the input image data, etc.

An intermediate image is an image that is obtained by detecting a change over time (image motion) in input image data and interpolating the detected motion. Obtaining an intermediate image by this method is called motion compensation.

Next, a specific example of the frame rate conversion method will be described. According to this method, frame rate conversion by any rational number (n/m) can be realized. Here, n and m are integers of 1 or more. The frame rate conversion method in this embodiment can be handled by dividing it into a first step and a second step. Here, the first step is a step of converting the frame rate by any rational number (n/m). Here, a basic image may be used as the interpolated image, or an intermediate image obtained by motion compensation may be used as the interpolated image. The second step is a step for creating a plurality of different images (sub-images) from the input image data or each image subjected to frame rate conversion in the first step, and displaying the plurality of sub-images in succession in time. By using the method according to the second step, it is also possible to make the human eye perceive that the original image is displayed, even though a plurality of different images are actually displayed.

In addition, the frame rate conversion method in this embodiment may use both the first step and the second step, may omit the first step and use only the second step, or may omit the second step and use only the first step.

First, as a first step, frame rate conversion by an arbitrary rational number (n/m) will be described. (See FIG. 68.) In FIG. 68, the horizontal axis is time, and the vertical axis is a diagram showing cases for various n and m. The figure in FIG. 68 shows a schematic diagram of the image to be displayed, and the horizontal position indicates the timing of display. Furthermore, the points displayed in the figure show the movement of the image. However, this is an example for explanation, and the displayed image is not limited to this. This method can be applied to various images.

The period Tin represents the period of the input image data. The period of the input image data corresponds to the input frame rate. For example, if the input frame rate is 60 Hz, the period of the input image data is 1/60 seconds. Similarly, if the input frame rate is 50 Hz,
The period of the input image data is 1/50 seconds. Thus, the period of the input image data (unit:
The number of frames per second is the reciprocal of the input frame rate (unit: Hz). Note that various input frame rates can be used. For example, 24 Hz, 50 Hz, 60 Hz, 70 Hz,
Examples of the frequency include 48 Hz, 100 Hz, 120 Hz, and 140 Hz.
4 Hz is a frame rate used for film movies, etc. 50 Hz is a frame rate used for PAL standard video signals, etc. 60 Hz is a frame rate used for NTSC standard video signals, etc. 70 Hz is a frame rate used for personal computer display input signals, etc. 48 Hz, 100 Hz, 120 Hz,
The frame rate of 140 Hz is twice as high as the above. However, the frame rate is not limited to twice as high, and may be any multiple of the above. In this manner, the method described in this embodiment can realize frame rate conversion for input signals of various standards.

The procedure for converting the frame rate by an arbitrary rational number (n/m) in the first step is as follows.
In step 1, the kth interpolation image (k is an integer equal to or greater than 1; the initial value is 1) for the first basic image is calculated.
The display timing of the kth interpolated image is set to be the time when a period equal to k (m/n) times the period of the input image data has elapsed since the first basic image was displayed.
In step 2, it is determined whether the coefficient k(m/n) used to determine the display timing of the kth interpolation image is an integer. If it is an integer, the (k(m/n)+1)th basic image is displayed at the display timing of the kth interpolation image, and the first step is terminated. If it is not an integer, proceed to step 3.
In step 3, an image to be used as the k-th interpolated image is determined. Specifically, the coefficient k(m/n) used to determine the display timing of the k-th interpolated image is converted to the form x+y/n. Here, x and y are integers, and y is a number smaller than n. If the k-th interpolated image is to be an intermediate image obtained by motion compensation, the k-th interpolated image is converted to the (x+1
The intermediate image is obtained by multiplying the image movement from the (x)th basic image to the (x+2)th basic image by (y/n). When the kth interpolated image is the same as the basic image, the (x+1)th basic image can be used. Note that the method of obtaining an intermediate image by multiplying the image movement by (y/n) will be described in detail elsewhere.
In step 4, the target interpolated image is moved to the next interpolated image. Specifically, the value of k is incremented by 1, and the process returns to step 1.

Next, the procedure in the first step will be described in detail by showing specific values of n and m.

The mechanism for executing the procedure in the first step may be implemented in the device, or may be determined in advance at the design stage of the device. If the mechanism for executing the procedure in the first step is implemented in the device, it becomes possible to switch the driving method so that the optimum operation is performed according to the situation. The situation here refers to the contents of the image data, the environment inside and outside the device (temperature, humidity, air pressure, light, sound, magnetic field, electric field, radiation amount,
altitude, acceleration, moving speed, etc.), user settings, software version, etc. On the other hand, if the mechanism for executing the procedure in the first step is predetermined at the design stage of the device, it is possible to use a drive circuit optimal for each drive method, and further, since the mechanism is already determined, a reduction in manufacturing costs can be expected due to mass production economies.

When n=1, m=1, that is, when the conversion ratio (n/m) is 1 (where n=1, m=1 in FIG. 68), the operation in the first step is as follows. First, when k=1, in step 1, the display timing of the first interpolated image for the first basic image is determined. The display timing of the first interpolated image is determined by multiplying the period of the input image data by k (m
/n), i.e., the point in time when a period equal to 1 has elapsed.

Next, in step 2, it is determined whether the coefficient k(m/n) used to determine the display timing of the first interpolation image is an integer. Here, the coefficient k(m/n) is 1, so it is an integer. Therefore, at the display timing of the first interpolation image, the (k(m/n)+1)th basic image, i.e., the second basic image, is displayed, and the first step is completed.

That is, when the conversion ratio is 1, the kth image is a basic image, the k+1th image is also a basic image, and the image display period is one time the period of the input image data.

Specifically, when the conversion ratio is 1 (n/m=1),
The i-th (i is a positive integer) image data;
The (i+1)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
A method for driving a display device that sequentially displays an image having a period equal to that of input image data, the image having a period equal to that of input image data, the image having a period equal to that of input image data, the method comprising the steps of:
The kth image is displayed according to the ith image data;
The k+1th image is displayed according to the i+1th image data.

Here, when the conversion ratio is 1, it is possible to omit the frame rate conversion circuit, which is advantageous in that the manufacturing cost can be reduced. Furthermore, when the conversion ratio is 1, it is advantageous in that the quality of the moving image can be improved compared to when the conversion ratio is smaller than 1. Furthermore, when the conversion ratio is 1, it is advantageous in that the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 1.

When n=2, m=1, that is, when the conversion ratio (n/m) is 2 (where n=2, m=1 in FIG. 68), the operation in the first step is as follows. First, when k=1, in step 1, the display timing of the first interpolated image for the first basic image is determined. The display timing of the first interpolated image is determined by multiplying the period of the input image data by k (m
/n), i.e., 1/2, of the period has elapsed.

Next, in step 2, it is determined whether the coefficient k (m/n) used to determine the display timing of the first interpolated image is an integer. Here, the coefficient k (m/n) is 1/2, so it is not an integer. Therefore, the process proceeds to step 3.

In step 3, an image to be used as the first interpolated image is determined. To do this, the coefficient 1/2 is subtracted from x
+y/n. In the case of the coefficient 1/2, x=0, y=1. If the first interpolated image is an intermediate image obtained by motion compensation, the first interpolated image is converted to the (x+
1) That is, the intermediate image is obtained as an image corresponding to a movement of y/n times, i.e., 1/2, the movement of the image from the first basic image to the (x+2)th, i.e., the second basic image.
When the (x+1)th interpolated image is to be the same as the basic image, the (x+1)th, ie, the first basic image can be used.

By the above steps, the display timing of the first interpolated image and the image to be displayed as the first interpolated image can be determined. Next, in step 4, the target interpolated image is shifted from the first interpolated image to the second interpolated image. That is, k is changed from 1 to 2, and the process returns to step 1.

When k=2, the display timing of the second interpolated image for the first basic image is determined in step 1. The display timing of the second interpolated image is the point in time when a period equal to k(m/n) times the period of the input image data, i.e., 1 times, has elapsed since the first basic image was displayed.

Next, in step 2, it is determined whether the coefficient k(m/n) used to determine the display timing of the second interpolation image is an integer. Here, the coefficient k(m/n) is 1, so it is an integer. Therefore, at the display timing of the second interpolation image, the (k(m/n)+1)th basic image, i.e., the second basic image, is displayed, and the first step is completed.

That is, when the conversion ratio is 2 (n/m=2),
The kth image is a base image,
The k+1th image is an interpolated image,
The (k+2)th image is a basic image, and is characterized in that the image display period is 1/2 the period of the input image data.

Specifically, when the conversion ratio is 2 (n/m=2),
The i-th (i is a positive integer) image data;
The (i+1)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
A method for driving a display device that sequentially displays an image (k+2) at an interval that is 1/2 the period of input image data, comprising:
The kth image is displayed according to the ith image data;
The k+1 image is displayed according to image data corresponding to a movement obtained by multiplying by half the movement from the i image data to the i+1 image data;
The k+2th image is displayed according to the i+1th image data.

As another specific expression, when the conversion ratio is 2 (n/m=2),
The i-th (i is a positive integer) image data;
The (i+1)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
A method for driving a display device that sequentially displays an image (k+2) at an interval that is 1/2 the period of input image data, comprising:
The kth image is displayed according to the ith image data;
The (k+1)th image is displayed according to the ith image data;
The k+2th image is displayed according to the i+1th image data.

Specifically, when the conversion ratio is 2, it is called double speed drive, or simply double speed drive.
For example, if the input frame rate is 60 Hz, the display frame rate will be 120 Hz (
The image is displayed twice in succession for one input image. If the interpolated image is an intermediate image obtained by motion compensation, the motion of the moving image can be made smoother, and the quality of the moving image can be significantly improved. Furthermore, if the display device is an active matrix liquid crystal display device,
It brings about a particularly remarkable effect of improving image quality. This is related to the problem of insufficient writing voltage caused by so-called dynamic capacitance, in which the capacitance of the liquid crystal element fluctuates with the applied voltage. That is, by making the display frame rate higher than the input frame rate, the frequency of the image data writing operation can be increased, so that problems such as video tailing and afterimages caused by insufficient writing voltage due to dynamic capacitance can be reduced. Furthermore, it is also effective to combine the AC drive and 120 Hz drive of the liquid crystal display device. That is, by setting the drive frequency of the liquid crystal display device to 120 Hz and setting the frequency of the AC drive to an integer multiple or an integer fraction of that frequency (for example, 30 Hz, 60 Hz, 120 Hz, 240 Hz, etc.), the flicker that appears due to the AC drive can be reduced to a level that is not perceptible to the human eye.

When n=3, m=1, that is, when the conversion ratio (n/m) is 3 (where n=3, m=1 in FIG. 68), the operation in the first step is as follows. First, when k=1, in step 1, the display timing of the first interpolated image for the first basic image is determined. The display timing of the first interpolated image is determined by multiplying the period of the input image data by k (m
/n), i.e., 1/3, of the period has elapsed.

Next, in step 2, it is determined whether the coefficient k (m/n) used to determine the display timing of the first interpolated image is an integer. Here, the coefficient k (m/n) is 1/3, so it is not an integer. Therefore, the process proceeds to step 3.

In step 3, an image to be used as the first interpolated image is determined. To do this, the coefficient 1/3 is subtracted from x
+y/n. In the case of the coefficient 1/3, x=0, y=1. If the first interpolated image is an intermediate image obtained by motion compensation, the first interpolated image is converted to the (x+
1) That is, the intermediate image is obtained as an image corresponding to a movement of y/n times, i.e., 1/3 times, the movement of the image from the first basic image to the (x+2)th, i.e., the second basic image.
When the (x+1)th interpolated image is to be the same as the basic image, the (x+1)th, ie, the first basic image can be used.

By the above steps, the display timing of the first interpolated image and the image to be displayed as the first interpolated image can be determined. Next, in step 4, the target interpolated image is shifted from the first interpolated image to the second interpolated image. That is, k is changed from 1 to 2, and the process returns to step 1.

When k=2, the display timing of the second interpolated image for the first basic image is determined in step 1. The display timing of the second interpolated image is the point in time when a period equal to k(m/n) times, i.e., 2/3 times, the period of the input image data has elapsed since the first basic image was displayed.

Next, in step 2, it is determined whether the coefficient k(m/n) used to determine the display timing of the second interpolated image is an integer. Here, the coefficient k(m/n) is 2/3, so it is not an integer. Therefore, the process proceeds to step 3.

In step 3, the image to be used as the second interpolated image is determined. To do this, the coefficient 2/3 is subtracted from x
+y/n. In the case of the coefficient 2/3, x=0, y=2. If the second interpolated image is an intermediate image obtained by motion compensation, the second interpolated image is converted to the (x+
1) That is, the intermediate image is obtained as an image corresponding to a movement of y/n times, i.e., 2/3 times, the movement of the image from the first basic image to the (x+2)th, i.e., the second basic image.
When the (x+1)th interpolated image is to be the same as the basic image, the (x+1)th, ie, the first basic image can be used.

By the above steps, the display timing of the second interpolated image and the image to be displayed as the second interpolated image can be determined. Next, in step 4, the target interpolated image is moved from the second interpolated image to the third interpolated image. That is, k is changed from 2 to 3, and the process returns to step 1.

When k=3, the display timing of the third interpolated image for the first basic image is determined in step 1. The display timing of the third interpolated image is the point in time when a period equal to k (m/n) times the period of the input image data, i.e., 1 times, has elapsed since the first basic image was displayed.

Next, in step 2, it is determined whether the coefficient k(m/n) used to determine the display timing of the third interpolation image is an integer. Here, the coefficient k(m/n) is 1, so it is an integer. Therefore, at the display timing of the third interpolation image, the (k(m/n)+1)th basic image, i.e., the second basic image, is displayed, and the first step is completed.

That is, when the conversion ratio is 3 (n/m=3),
The kth image is a base image,
The k+1th image is an interpolated image,
The k+2th image is an interpolated image,
The (k+3)th image is a basic image, and is characterized in that the image display period is 1/3 times the period of the input image data.

Specifically, when the conversion ratio is 3 (n/m=3),
The i-th (i is a positive integer) image data;
The (i+1)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
A method for driving a display device that sequentially displays an image (k+3) at an interval that is 1/3 times the period of input image data, comprising:
The kth image is displayed according to the ith image data;
The k+1 image is displayed according to image data corresponding to a movement obtained by multiplying by 1/3 the movement from the i image data to the i+1 image data;
The k+2 image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the i image to the i+1 image by 2/3;
The k+3rd image is displayed according to the i+1st image data.

As another specific expression, when the conversion ratio is 3 (n/m=3),
The i-th (i is a positive integer) image data;
The (i+1)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
A method for driving a display device that sequentially displays an image (k+3) at an interval that is 1/3 times the period of input image data, comprising:
The kth image is displayed according to the ith image data;
The (k+1)th image is displayed according to the ith image data;
The k+2 image is displayed according to the i image data;
The k+3rd image is displayed according to the i+1st image data.

Here, a conversion ratio of 3 has the advantage of being able to improve the quality of moving images compared to a conversion ratio smaller than 3. Furthermore, a conversion ratio of 3 has the advantage of being able to reduce power consumption and manufacturing costs compared to a conversion ratio larger than 3.

Specifically, when the conversion ratio is 3, it is also called triple-speed drive. For example, if the input frame rate is 60 Hz, the display frame rate is 180 Hz (180 Hz drive). For one input image, the image is displayed three times in succession. In this case, if the interpolated image is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, and the quality of the moving image can be significantly improved. Furthermore, if the display device is an active matrix liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, resulting in a particularly significant improvement in image quality against problems such as trailing and afterimages in moving images. Furthermore, the AC drive of the liquid crystal display device and the 180 Hz drive are
It is also effective to combine driving. That is, the driving frequency of the liquid crystal display device is 180H
z, and the frequency of the AC drive is an integer multiple or an integer fraction of that (for example, 45 Hz, 9
By setting the frequency to a value that is not noticeable to the human eye, flicker that occurs due to AC driving can be reduced to a level that is not noticeable to the human eye.

n=3, m=2, i.e., the conversion ratio (n/m) is 3/2 (n=3, m=2 in FIG. 68)
In the case of k=1, the operation in the first step is as follows.
Then, the display timing of the first interpolated image for the first basic image is determined. The display timing of the first interpolated image is determined by multiplying the period of the input image data by k after the first basic image is displayed.
This is the point in time when a period equal to (m/n), or 2/3, has elapsed.

Next, in step 2, it is determined whether the coefficient k (m/n) used to determine the display timing of the first interpolated image is an integer. Here, the coefficient k (m/n) is 2/3, so it is not an integer. Therefore, the process proceeds to step 3.

In step 3, an image to be used as the first interpolated image is determined. To do this, the coefficient 2/3 is subtracted from x
+y/n. In the case of the coefficient 2/3, x=0, y=2. If the first interpolated image is an intermediate image obtained by motion compensation, the first interpolated image is converted to the (x+
1) That is, the intermediate image is obtained as an image corresponding to a movement of y/n times, i.e., 2/3 times, the movement of the image from the first basic image to the (x+2)th, i.e., the second basic image.
When the (x+1)th interpolated image is to be the same as the basic image, the (x+1)th, ie, the first basic image can be used.

By the above steps, the display timing of the first interpolated image and the image to be displayed as the first interpolated image can be determined. Next, in step 4, the target interpolated image is shifted from the first interpolated image to the second interpolated image. That is, k is changed from 1 to 2, and the process returns to step 1.

When k=2, the display timing of the second interpolated image for the first basic image is determined in step 1. The display timing of the second interpolated image is the point in time when a period equal to k(m/n) times, i.e., 4/3 times, the period of the input image data has elapsed since the first basic image was displayed.

Next, in step 2, it is determined whether the coefficient k(m/n) used to determine the display timing of the second interpolated image is an integer. Here, the coefficient k(m/n) is 4/3, so it is not an integer. Therefore, the process proceeds to step 3.

In step 3, the image to be used as the second interpolated image is determined. To do this, the coefficient 4/3 is subtracted from x
+y/n. In the case of the coefficient 4/3, x=1, y=1. If the second interpolated image is an intermediate image obtained by motion compensation, the second interpolated image is converted to the (x+
1) That is, the intermediate image is obtained as an image corresponding to a movement of y/n times, i.e., 1/3 times, the movement of the image from the second basic image to the (x+2)th, i.e., the third basic image.
When the (x+1)th interpolated image is to be the same as the basic image, the (x+1)th, ie, second basic image can be used.

By the above steps, the display timing of the second interpolated image and the image to be displayed as the second interpolated image can be determined. Next, in step 4, the target interpolated image is moved from the second interpolated image to the third interpolated image. That is, k is changed from 2 to 3, and the process returns to step 1.

When k=3, the display timing of the third interpolated image for the first basic image is determined in step 1. The display timing of the third interpolated image is the point in time when a period equal to k (m/n) times, i.e., twice, the period of the input image data has elapsed since the first basic image was displayed.

Next, in step 2, it is determined whether the coefficient k(m/n) used to determine the display timing of the third interpolation image is an integer. Here, the coefficient k(m/n) is 2, so it is an integer. Therefore, at the display timing of the third interpolation image, the (k(m/n)+1)th basic image, i.e., the third basic image, is displayed, and the first step is completed.

That is, when the conversion ratio is 3/2 (n/m=3/2),
The kth image is a base image,
The k+1th image is an interpolated image,
The k+2th image is an interpolated image,
The (k+3)th image is a basic image, and is characterized in that the image display period is 2/3 times the period of the input image data.

Specifically, when the conversion ratio is 3/2 (n/m=3/2),
The i-th (i is a positive integer) image data;
The (i+1)th image data;
The (i+2)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
A method for driving a display device that sequentially displays an image (k+3) at an interval that is 2/3 times the period of input image data, comprising:
The kth image is displayed according to the ith image data;
The k+1 image is displayed according to image data corresponding to a movement obtained by multiplying by 2/3 the movement from the i image data to the i+1 image data;
The k+2 image is a motion of 1/3 from the i+1 image to the i+2 image.
The image data is displayed according to the multiplied movement.
The k+3 image is displayed according to the i+2 image data.

As another specific expression, when the conversion ratio is 3/2 (n/m=3/2),
The i-th (i is a positive integer) image data;
The (i+1)th image data;
The (i+2)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
A method for driving a display device that sequentially displays an image (k+3) at an interval that is 2/3 times the period of input image data, comprising:
The kth image is displayed according to the ith image data;
The (k+1)th image is displayed according to the ith image data;
the k+2 image is displayed according to the i+1 image data;
The k+3 image is displayed according to the i+2 image data.

Here, when the conversion ratio is 3/2, there is an advantage that the quality of the moving image can be improved compared to when the conversion ratio is smaller than 3/2.
This has the advantage that power consumption and manufacturing costs can be reduced compared to when the number of inputs is greater than two.

Specifically, when the conversion ratio is 3/2, it is also called 3/2-times speed drive or 1.5-times speed drive. For example, if the input frame rate is 60 Hz, the display frame rate is 90
Hz (90 Hz drive). For two input images, the image is displayed three times in succession. In this case, if the interpolated image is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, and the quality of the moving image can be significantly improved. In particular, compared with driving methods with high driving frequencies such as 120 Hz drive (double speed drive) and 180 Hz drive (triple speed drive), the operating frequency of the circuit that obtains the intermediate image by motion compensation can be reduced, allowing the use of inexpensive circuits and reducing manufacturing costs and power consumption. Furthermore, if the display device is an active matrix liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, and therefore trailing of moving images,
This brings about a particularly remarkable effect of improving image quality with respect to defects such as residual images. Furthermore, it is also effective to combine the AC drive and 90 Hz drive of the liquid crystal display device. That is, while the drive frequency of the liquid crystal display device is set to 90 Hz, the AC drive frequency is set to an integer multiple or an integer fraction of that frequency (for example, 3
By setting the frequency to a value that is not noticeable to the human eye, flicker that occurs due to AC driving can be reduced to a level that is not noticeable to the human eye.

For positive integers n and m other than those mentioned above, the details of the procedure are omitted, but by following the procedure of frame rate conversion in the first step, the conversion ratio can be set as an arbitrary rational number (n/m).
For combinations in which m) can be reduced, the conversion ratios can be treated in the same way as the conversion ratios after reduction.

For example, when n=4, m=1, that is, the conversion ratio (n/m) is 4 (where n=4, m=1 in FIG. 68),
The kth image is a base image,
The k+1th image is an interpolated image,
The k+2th image is an interpolated image,
The k+3th image is an interpolated image,
The (k+4)th image is a basic image, and is characterized in that the image display period is 1/4 times the period of the input image data.

More specifically, when the conversion ratio is 4 (n/m=4),
The i-th (i is a positive integer) image data;
The (i+1)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
The k+3th image;
A method for driving a display device that sequentially displays an image (k+4) at an interval of 1/4 times the period of input image data, comprising:
The kth image is displayed according to the ith image data;
The k+1 image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the i image data to the i+1 image data by 1/4;
The k+2 image is displayed according to image data corresponding to a movement obtained by multiplying by half the movement from the i image data to the i+1 image data;
The k+3 image is displayed according to image data corresponding to a movement obtained by multiplying by 3/4 the movement from the i image data to the i+1 image data;
The k+4th image is displayed according to the i+1th image data.

As another specific expression, when the conversion ratio is 4 (n/m=4),
The i-th (i is a positive integer) image data;
The (i+1)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
The k+3th image;
A method for driving a display device that sequentially displays an image (k+4) at an interval of 1/4 times the period of input image data, comprising:
The kth image is displayed according to the ith image data;
The (k+1)th image is displayed according to the ith image data;
The k+2 image is displayed according to the i image data;
The (k+3) image is displayed according to the i image data;
The k+4th image is displayed according to the i+1th image data.

Here, a conversion ratio of 4 has the advantage of being able to improve the quality of moving images compared to a conversion ratio smaller than 4. Furthermore, a conversion ratio of 4 has the advantage of being able to reduce power consumption and manufacturing costs compared to a conversion ratio larger than 4.

Specifically, when the conversion ratio is 4, it is also called quadruple speed drive. For example, if the input frame rate is 60 Hz, the display frame rate is 240 Hz (240 Hz drive). Then, for one input image, the image is displayed four times in succession. In this case, if the interpolated image is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, and the quality of the moving image can be significantly improved. In particular, when the input frame rate is 60 Hz, the display frame rate is 240 Hz (240 Hz drive). Then, for one input image, the image is displayed four times in succession. In this case, when the interpolated image is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, and the quality of the moving image can be significantly improved.
Compared with driving methods with small driving frequencies such as 180Hz driving (double speed driving) and 180Hz driving (triple speed driving), intermediate images obtained by more accurate motion compensation can be used as interpolated images, making the motion of the moving image smoother and significantly improving the quality of the moving image. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, resulting in a particularly significant improvement in image quality against problems such as trailing and afterimages in moving images. Furthermore, it is also effective to combine the AC driving and 240Hz driving of the liquid crystal display device. That is, by setting the driving frequency of the liquid crystal display device to 240Hz and setting the frequency of the AC driving to an integer multiple or an integer fraction of that frequency (for example, 30Hz, 40Hz, 60Hz, 120Hz, etc.), the flicker caused by the AC driving can be reduced to a level that is not perceptible to the human eye.

Furthermore, for example, n=4, m=3, that is, the conversion ratio (n/m) is 4/3 (n=
4, m = 3),
The kth image is a base image,
The k+1th image is an interpolated image,
The k+2th image is an interpolated image,
The k+3th image is an interpolated image,
The (k+4)th image is a basic image, and is characterized in that the image display period is 3/4 times the period of the input image data.

More specifically, when the conversion ratio is 4/3 (n/m=4/3),
The i-th (i is a positive integer) image data;
The (i+1)th image data;
The (i+2)th image data;
The (i+3)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
The k+3th image;
A method for driving a display device that sequentially displays an image (k+4) at an interval of 3/4 times the period of input image data, comprising:
The kth image is displayed according to the ith image data;
The k+1 image is displayed according to image data corresponding to a movement obtained by multiplying by 3/4 the movement from the i image data to the i+1 image data;
The k+2 image is a motion of 1/2 from the i+1 image to the i+2 image.
The image data is displayed according to the multiplied movement.
The k+3 image is a quarter of the movement from the i+2 image to the i+3 image.
The image data is displayed according to the multiplied movement.
The k+4th image is displayed according to the i+3rd image data.

As another specific expression, when the conversion ratio is 4/3 (n/m=4/3),
The i-th (i is a positive integer) image data;
The (i+1)th image data;
The (i+2)th image data;
The (i+3)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
The k+3th image;
A method for driving a display device that sequentially displays an image (k+4) at an interval of 3/4 times the period of input image data, comprising:
The kth image is displayed according to the ith image data;
The (k+1)th image is displayed according to the ith image data;
the k+2 image is displayed according to the i+1 image data;
The (k+3) image is displayed according to the (i+2) image data;
The k+4th image is displayed according to the i+3rd image data.

Here, when the conversion ratio is 4/3, there is an advantage that the quality of the moving image can be improved compared to when the conversion ratio is smaller than 4/3.
This has the advantage that power consumption and manufacturing costs can be reduced compared to when the number of inputs is greater than three.

Specifically, when the conversion ratio is 4/3, it is also called 4/3-times speed drive or 1.25-times speed drive. For example, if the input frame rate is 60 Hz, the display frame rate is 8
0 Hz (80 Hz drive). For three input images, the image is displayed four times in succession. In this case, if the interpolated image is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, and the quality of the moving image can be significantly improved. In particular, compared with driving methods with high driving frequencies such as 120 Hz drive (double speed drive) and 180 Hz drive (triple speed drive), the operating frequency of the circuit that obtains the intermediate image by motion compensation can be reduced, so that an inexpensive circuit can be used and manufacturing costs and power consumption can be reduced. Furthermore, if the display device is an active matrix liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, resulting in a particularly significant improvement in image quality against problems such as video tailing and afterimages. Furthermore, it is also effective to combine the AC drive and 80 Hz drive of the liquid crystal display device. That is, while the drive frequency of the liquid crystal display device is 80 Hz, the frequency of the AC drive can be set to an integer multiple or an integer fraction of that (for example,
By setting the frequency to a value that is not noticeable to the human eye, it is possible to reduce flicker that occurs due to AC driving.

Furthermore, for example, n=5, m=1, that is, the conversion ratio (n/m) is 5 (n=5 in FIG. 68,
In the case of m = 1,
The kth image is a base image,
The k+1th image is an interpolated image,
The k+2th image is an interpolated image,
The k+3th image is an interpolated image,
The k+4th image is an interpolated image,
The (k+5)th image is a basic image, and is characterized in that the image display period is 1/5 times the period of the input image data.

More specifically, when the conversion ratio is 5 (n/m=5),
The i-th (i is a positive integer) image data;
The (i+1)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
The k+3th image;
The k+4th image;
A method for driving a display device that sequentially displays an image (a) and an image (b) at an interval that is 1/5 times the period of input image data, the method comprising the steps of:
The kth image is displayed according to the ith image data;
The k+1 image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the i image data to the i+1 image data by 1/5;
The k+2 image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the i image data to the i+1 image data by 2/5;
The k+3 image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the i image data to the i+1 image data by 3/5;
The k+4th image is displayed according to image data corresponding to a movement obtained by multiplying by 4/5 the movement from the ith image data to the i+1th image data;
The k+5th image is displayed according to the i+1th image data.

As another specific expression, when the conversion ratio is 5 (n/m=5),
The i-th (i is a positive integer) image data;
The (i+1)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
The k+3th image;
The k+4th image;
A method for driving a display device that sequentially displays an image (a) and an image (b) at an interval that is 1/5 times the period of input image data, the method comprising the steps of:
The kth image is displayed according to the ith image data;
The (k+1)th image is displayed according to the ith image data;
The k+2 image is displayed according to the i image data;
The (k+3) image is displayed according to the i image data;
The k+4th image is displayed according to the i image data;
The k+5th image is displayed according to the i+1th image data.

Here, a conversion ratio of 5 has the advantage of being able to improve the quality of moving images compared to a conversion ratio of less than 5. Furthermore, a conversion ratio of 5 has the advantage of being able to reduce power consumption and manufacturing costs compared to a conversion ratio of more than 5.

Specifically, when the conversion ratio is 5, it is also called 5x speed drive. For example, if the input frame rate is 60 Hz, the display frame rate is 300 Hz (300 Hz drive). Then, for one input image, the image is displayed five times in succession. In this case, if the interpolated image is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, and the quality of the moving image can be significantly improved. In particular, when the input frame rate is 60 Hz, the display frame rate is 300 Hz (300 Hz drive). Then, for one input image, the image is displayed five times in succession. In this case, when the interpolated image is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, and the quality of the moving image can be significantly improved.
Compared with driving methods with small driving frequencies such as 180Hz driving (double speed driving) and 180Hz driving (triple speed driving), intermediate images obtained by more accurate motion compensation can be used as interpolated images, making the motion of the moving image smoother and significantly improving the quality of the moving image. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, resulting in a particularly significant improvement in image quality against problems such as trailing and afterimages in moving images. Furthermore, it is also effective to combine the AC driving and 300Hz driving of the liquid crystal display device. That is, by setting the driving frequency of the liquid crystal display device to 300Hz and setting the frequency of the AC driving to an integer multiple or an integer fraction of that frequency (for example, 30Hz, 50Hz, 60Hz, 100Hz, etc.), the flicker caused by the AC driving can be reduced to a level that is not perceptible to the human eye.

Furthermore, for example, n=5, m=2, that is, the conversion ratio (n/m) is 5/2 (n=
5, m = 2),
The kth image is a base image,
The k+1th image is an interpolated image,
The k+2th image is an interpolated image,
The k+3th image is an interpolated image,
The k+4th image is an interpolated image,
The (k+5)th image is a basic image, and is characterized in that the image display period is 1/5 times the period of the input image data.

More specifically, when the conversion ratio is 5/2 (n/m=5/2),
The i-th (i is a positive integer) image data;
The (i+1)th image data;
The (i+2)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
The k+3th image;
The k+4th image;
A method for driving a display device that sequentially displays an image (a) and an image (b) at an interval that is 1/5 times the period of input image data, the method comprising the steps of:
The kth image is displayed according to the ith image data;
The k+1 image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the i image data to the i+1 image data by 2/5;
The k+2 image is displayed according to image data corresponding to a movement obtained by multiplying by 4/5 the movement from the i image data to the i+1 image data;
The k+3 image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the i+1 image data to the i+2 image data by 1/5;
The k+4th image is displayed according to image data corresponding to a movement obtained by multiplying by 3/5 the movement from the i+1th image data to the i+2th image data;
The k+5th image is displayed according to the i+2th image data.

As another specific expression, when the conversion ratio is 5/2 (n/m=5/2),
The i-th (i is a positive integer) image data;
The (i+1)th image data;
The (i+2)th image data is input in sequence at a constant cycle as input image data,
A kth image (k is a positive integer),
The k+1th image;
The k+2th image;
The k+3th image;
The k+4th image;
A method for driving a display device that sequentially displays an image (a) and an image (b) at an interval that is 1/5 times the period of input image data, the method comprising the steps of:
The kth image is displayed according to the ith image data;
The (k+1)th image is displayed according to the ith image data;
The k+2 image is displayed according to the i image data;
the (k+3) image is displayed according to the (i+1) image data;
The (k+4)th image is displayed according to the (i+1)th image data;
The k+5th image is displayed according to the i+2th image data.

Here, a conversion ratio of 5/2 has the advantage of being able to improve the quality of moving images compared to a conversion ratio smaller than 5/2. Furthermore, a conversion ratio of 5/2 has the advantage of being able to reduce power consumption and manufacturing costs compared to a conversion ratio larger than 5.

Specifically, when the conversion ratio is 5, it is also called 5/2x speed drive or 2.5x speed drive. For example, if the input frame rate is 60 Hz, the display frame rate is 150H.
z (150 Hz drive). For two input images, the image is displayed five times in succession. In this case, if the interpolated image is an intermediate image obtained by motion compensation, the motion of the moving image can be made smoother, and the quality of the moving image can be significantly improved. In particular, compared with a driving method with a low driving frequency such as 120 Hz drive (double speed drive), an intermediate image obtained by more accurate motion compensation can be used as an interpolated image, and the motion of the moving image can be made smoother, and the quality of the moving image can be significantly improved. Furthermore, compared with a driving method with a high driving frequency such as 180 Hz drive (triple speed drive), the operating frequency of the circuit for obtaining the intermediate image can be reduced by motion compensation, and therefore an inexpensive circuit can be used, and the manufacturing cost and power consumption can be reduced. Furthermore, when the display device is an active matrix type liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, and therefore the image quality can be improved significantly against obstacles such as trailing and afterimages in the moving image. Furthermore, it is also effective to combine the AC drive and 150 Hz drive of the liquid crystal display device. That is, when the drive frequency of the liquid crystal display device is set to 150 Hz,
While setting the frequency of the AC drive to an integer multiple or an integer fraction (for example, 30 Hz, 50
By setting the frequency to a desired frequency (such as 75 Hz, 150 Hz, etc.), flicker caused by AC driving can be reduced to a level that is not perceptible to the human eye.

In this way, by setting the positive integers n and m in various ways, the conversion ratio can be set as an arbitrary rational number (n/m). Although a detailed explanation is omitted, when n is in the range of 10 or less,
n = 1, m = 1, i.e., conversion ratio (n/m) = 1 (1x speed drive, 60 Hz),
n = 2, m = 1, i.e., conversion ratio (n/m) = 2 (2x speed drive, 120 Hz),
n = 3, m = 1, i.e., conversion ratio (n/m) = 3 (triple speed drive, 180 Hz),
n = 3, m = 2, that is, the conversion ratio (n/m) = 3/2 (3/2 times speed drive, 90 Hz),
n = 4, m = 1, i.e., conversion ratio (n/m) = 4 (4x speed drive, 240 Hz),
n = 4, m = 3, that is, the conversion ratio (n/m) = 4/3 (4/3 times speed drive, 80 Hz),
n = 5, m = 1, i.e., conversion ratio (n/m) = 5/1 (5x speed drive, 300 Hz),
n = 5, m = 2, i.e., conversion ratio (n/m) = 5/2 (5/2x speed drive, 150Hz),
n = 5, m = 3, that is, the conversion ratio (n/m) = 5/3 (5/3 times speed drive, 100 Hz),
n = 5, m = 4, i.e., conversion ratio (n/m) = 5/4 (5/4x speed drive, 75 Hz),
n = 6, m = 1, i.e., conversion ratio (n/m) = 6 (6x speed drive, 360 Hz),
n = 6, m = 5, i.e., conversion ratio (n/m) = 6/5 (6/5x speed drive, 72Hz),
n = 7, m = 1, i.e., conversion ratio (n/m) = 7 (7x speed drive, 420Hz),
n = 7, m = 2, i.e., conversion ratio (n/m) = 7/2 (7/2x speed drive, 210Hz),
n = 7, m = 3, that is, the conversion ratio (n/m) = 7/3 (7/3 times speed drive, 140 Hz),
n = 7, m = 4, i.e., conversion ratio (n/m) = 7/4 (7/4x speed drive, 105 Hz),
n = 7, m = 5, i.e., conversion ratio (n/m) = 7/5 (7/5x speed drive, 84Hz),
n = 7, m = 6, i.e., conversion ratio (n/m) = 7/6 (7/6x speed drive, 70Hz),
n = 8, m = 1, i.e., conversion ratio (n/m) = 8 (8x speed drive, 480 Hz),
n = 8, m = 3, that is, the conversion ratio (n/m) = 8/3 (8/3 times speed drive, 160 Hz),
n=8, m=5, i.e., conversion ratio (n/m)=8/5 (8/5x speed drive, 96Hz),
n = 8, m = 7, i.e., conversion ratio (n/m) = 8/7 (8/7x speed drive, 68.6Hz)
,
n = 9, m = 1, i.e., conversion ratio (n/m) = 9 (9x speed drive, 540 Hz),
n = 9, m = 2, i.e., conversion ratio (n/m) = 9/2 (9/2x speed drive, 270Hz),
n = 9, m = 4, i.e., conversion ratio (n/m) = 9/4 (9/4x speed drive, 135 Hz),
n = 9, m = 5, i.e., conversion ratio (n/m) = 9/5 (9/5x speed drive, 108Hz),
n = 9, m = 7, i.e., conversion ratio (n/m) = 9/7 (9/7x speed drive, 77.1Hz)
,
n = 9, m = 8, i.e., conversion ratio (n/m) = 9/8 (9/8x speed drive, 67.5Hz)
,
n = 10, m = 1, i.e., conversion ratio (n/m) = 10 (10x speed drive, 600 Hz),
n = 10, m = 3, that is, conversion ratio (n/m) = 10/3 (10/3x speed drive, 200H
z),
n = 10, m = 7, that is, the conversion ratio (n/m) = 10/7 (10/7 times speed drive, 85.7
Hz),
n = 10, m = 9, that is, the conversion ratio (n/m) = 10/9 (10/9 times speed drive, 66.7
Hz),
The above combinations are possible. Note that the frequency notation is an example when the input frame rate is 60 Hz, and for other input frame rates, the value obtained by multiplying the input frame rate by the respective conversion ratio becomes the drive frequency.

In addition, in the case where n is an integer greater than 10, no specific values of n and m are given, but it is clear that the frame rate conversion procedure in the first step can be applied to various values of n and m.

The conversion ratio can be determined depending on the extent to which the images to be displayed are contained in the input image data that can be displayed without motion compensation. Specifically, the smaller m is, the greater the proportion of images that can be displayed in the input image data without motion compensation. If motion compensation is performed less frequently, the frequency of operation of the circuit that performs motion compensation can be reduced, thereby reducing power consumption, and further, the possibility of creating an image containing errors (an intermediate image that does not accurately reflect the motion of the image) can be reduced, thereby improving image quality. For example, when n is in the range of 10 or less, such conversion ratios include 1, 2, 3, 3/2, 4,
Examples of such a conversion ratio include 5, 5/2, 6, 7, 7/2, 8, 9, 9/2, and 10. By using such a conversion ratio, it is possible to improve the image quality and reduce power consumption, particularly when an intermediate image obtained by motion compensation is used as an interpolated image. This is because, when m is 2, the number of images that can be displayed without performing motion compensation on the input image data is relatively large (1/2 of the total number of input image data exists),
This is because the frequency of motion compensation is reduced. Furthermore, when m is 1, the number of images that can be displayed without performing motion compensation on the input image data is large (equal to the total number of input image data), and motion compensation is not performed. On the other hand, the larger m is, the more intermediate images created by highly accurate motion compensation can be used, which has the advantage of making image movement smoother.

If the display device is a liquid crystal display device, the conversion ratio can be determined according to the response time of the liquid crystal element. Here, the response time of the liquid crystal element is the time from when the voltage applied to the liquid crystal element is changed until the liquid crystal element responds. If the response time of the liquid crystal element varies depending on the amount of change in the voltage applied to the liquid crystal element, the average response time for a number of representative voltage changes can be used. Alternatively, the response time of the liquid crystal element can be determined according to MPRT (Movin
The time may be defined in IEEE 802.11g Picture Response Time.
Then, the conversion ratio can be determined by frame rate conversion so that the image display period is close to the response time of the liquid crystal element. Specifically, it is preferable that the response time of the liquid crystal element is a time from a value obtained by multiplying the period of the input image data and the inverse of the conversion ratio to a value about half this value. In this way, the image display period can be set to match the response time of the liquid crystal element, so that the image quality can be improved. For example, when the response time of the liquid crystal element is 4 milliseconds or more and 8 milliseconds or less, double speed driving (120 Hz drive) can be used. This is because the image display period of the 120 Hz drive is about 8 milliseconds, and half of the image display period of the 120 Hz drive is about 4 milliseconds. Similarly, for example, when the response time of the liquid crystal element is 3 milliseconds or more and 6 milliseconds or less, triple speed driving (180 Hz drive) can be used, and the response time of the liquid crystal element can be set to 5 milliseconds or less.
When the response time of the liquid crystal element is between 2 milliseconds and 4 milliseconds, it can be driven at 1.5 times the normal speed (90 Hz drive). When the response time of the liquid crystal element is between 2 milliseconds and 4 milliseconds, it can be driven at 4 times the normal speed (240 Hz drive). When the response time of the liquid crystal element is between 6 milliseconds and 12 milliseconds, it can be driven at 1.5 times the normal speed (90 Hz drive).
25 times faster (80 Hz drive). The same applies to other drive frequencies.

The conversion ratio can also be determined by a trade-off between the quality of the moving image and the power consumption and manufacturing costs. In other words, the quality of the moving image can be improved by increasing the conversion ratio, while the power consumption and manufacturing costs can be reduced by decreasing the conversion ratio. In other words, each conversion ratio in the range of n equal to or less than 10 has the following advantages.

When the conversion ratio is 1, the quality of moving images can be improved compared to when the conversion ratio is smaller than 1, and power consumption and manufacturing costs can be reduced compared to when the conversion ratio is larger than 1. Furthermore, since m is small, power consumption can be reduced while high image quality is obtained. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1 time the period of the input image data, image quality can be improved.

When the conversion ratio is 2, the quality of moving images can be improved compared to when the conversion ratio is smaller than 2, and power consumption and manufacturing costs can be reduced compared to when the conversion ratio is larger than 2. Furthermore, since m is small, power consumption can be reduced while high image quality is obtained. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/2 the period of the input image data, image quality can be improved.

When the conversion ratio is 3, the quality of moving images can be improved compared to when the conversion ratio is smaller than 3, and the power consumption and manufacturing costs can be reduced compared to when the conversion ratio is larger than 3. Furthermore, since m is small, it is possible to obtain high image quality while reducing power consumption. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/3 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 3/2, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 3/2, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 3/2. Furthermore, since m is small, it is possible to obtain high image quality while reducing power consumption. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 2/3 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 4, the quality of moving images can be improved compared to when the conversion ratio is smaller than 4, and power consumption and manufacturing costs can be reduced compared to when the conversion ratio is larger than 4. Furthermore, since m is small, power consumption can be reduced while high image quality is obtained. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/4 times the period of the input image data, image quality can be improved.

When the conversion ratio is 4/3, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 4/3, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 4/3. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 3/4 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 5, the quality of moving images can be improved compared to when the conversion ratio is smaller than 5, and power consumption and manufacturing costs can be reduced compared to when the conversion ratio is larger than 5. Furthermore, since m is small, power consumption can be reduced while high image quality is obtained. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/5 times the period of the input image data, image quality can be improved.

When the conversion ratio is 5/2, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 5/2, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 5/2. Furthermore, since m is small, it is possible to obtain high image quality while reducing power consumption. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 2/5 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 5/3, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 5/3, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 5/3. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 3/5 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 5/4, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 5/4, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 5/4. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 4/5 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 6, the quality of moving images can be improved compared to when the conversion ratio is smaller than 6, and power consumption and manufacturing costs can be reduced compared to when the conversion ratio is larger than 6. Furthermore, since m is small, power consumption can be reduced while high image quality is obtained. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/6 the period of the input image data, image quality can be improved.

When the conversion ratio is 6/5, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 6/5, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 6/5. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 5/6 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 7, the quality of moving images can be improved compared to when the conversion ratio is smaller than 7, and power consumption and manufacturing costs can be reduced compared to when the conversion ratio is larger than 7. Furthermore, since m is small, power consumption can be reduced while high image quality is obtained. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/7 times the period of the input image data, image quality can be improved.

When the conversion ratio is 7/2, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 7/2, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 7/2. Furthermore, since m is small, it is possible to obtain high image quality while reducing power consumption. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 2/7 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 7/3, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 7/3, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 7/3. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 3/7 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 7/4, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 7/4, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 7/4. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 4/7 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 7/5, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 7/5, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 7/5. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 5/7 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 7/6, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 7/6, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 7/6. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 6/7 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 8, the quality of moving images can be improved compared to when the conversion ratio is smaller than 8, and power consumption and manufacturing costs can be reduced compared to when the conversion ratio is larger than 8. Furthermore, since m is small, power consumption can be reduced while high image quality is obtained. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/8 times the period of the input image data, image quality can be improved.

When the conversion ratio is 8/3, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 8/3, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 8/3. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 3/8 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 8/5, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 8/5, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 8/5. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 5/8 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 8/7, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 8/7, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 8/7. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 7/8 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 9, the quality of moving images can be improved compared to when the conversion ratio is smaller than 9, and power consumption and manufacturing costs can be reduced compared to when the conversion ratio is larger than 9. Furthermore, since m is small, power consumption can be reduced while high image quality is obtained. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/9 times the period of the input image data, image quality can be improved.

When the conversion ratio is 9/2, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 9/2, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 9/2. Furthermore, since m is small, it is possible to obtain high image quality while reducing power consumption. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 2/9 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 9/4, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 9/4, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 9/4. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 4/9 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 9/5, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 9/5, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 9/5. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 5/9 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 9/7, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 9/7, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 9/7. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 7/9 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 9/8, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 9/8, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 9/8. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 8/9 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 10, the quality of the video can be improved more than when the conversion ratio is less than 10;
The power consumption and manufacturing cost can be reduced compared to the case where the conversion ratio is greater than 10.
Since the response time is small, it is possible to obtain high image quality while reducing power consumption. Furthermore, by applying the present invention to a liquid crystal display device in which the response time of the liquid crystal element is about 1/10 of the period of the input image data,
The image quality can be improved.

When the conversion ratio is 10/3, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 10/3, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 10/3. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 3/10 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 10/7, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 10/7, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 10/7. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 7/10 times the period of the input image data, the image quality can be improved.

When the conversion ratio is 10/9, the quality of the moving image can be improved compared to when the conversion ratio is smaller than 10/9, and the power consumption and manufacturing cost can be reduced compared to when the conversion ratio is larger than 10/9. Furthermore, since m is large, the movement of the image can be made smoother. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 9/10 times the period of the input image data, the image quality can be improved.

It is apparent that the same advantages are obtained for each conversion ratio in the range where n is greater than 10.

Next, in the second step, a method is described in which a plurality of different images (sub-images) are created from an image according to the input image data or each image (hereinafter referred to as an original image) whose frame rate has been converted by an arbitrary rational number (n/m) times in the first step, and the plurality of sub-images are presented in a time-series manner. By doing so, it is possible to make the human eye perceive as if a single original image were displayed, even though a plurality of images are actually presented.

In this case, the sub-image that is displayed first among the sub-images created from one original image is called the first sub-image. Here, the timing of displaying the first sub-image is the same as the timing of displaying the original image determined in the first step.
The sub-image displayed thereafter is called the second sub-image. The timing of displaying the second sub-image can be determined arbitrarily, regardless of the timing of displaying the original image determined in the first step. The image actually displayed is an image created from the original image by the method in the second step. Various original images can also be used for creating the sub-image. The number of sub-images is not limited to two, and may be greater than two. In the second step, the number of sub-images is represented as J (J is an integer equal to or greater than 2). In this case, the sub-image displayed at the same timing as the timing of displaying the original image determined in the first step is called the first sub-image, and the sub-images displayed thereafter are called the second sub-image, the third sub-image, ... in the order of display.
, the Jth sub-image.

There are various methods for creating multiple sub-images from one original image, but the main methods include the following. One is to use the original image as a sub-image as is. One is to distribute the brightness of the original image to multiple sub-images. One is to use intermediate images obtained by motion compensation as sub-images.

Here, the method of distributing the brightness of the original image to the multiple sub-images can be further divided into multiple methods. The main methods include the following. One is a method in which at least one sub-image is a black image (hereinafter referred to as a black insertion method). The other is
This method divides the brightness of the original image into multiple ranges, and when controlling the brightness in each range, it is done by using only one of all the sub-images (hereinafter referred to as the time-division gradation control method).One method is to make one sub-image a bright image obtained by changing the gamma value of the original image, and the other sub-image a dark image obtained by changing the gamma value of the original image (hereinafter referred to as the gamma complement method).

Each of the above methods will be briefly explained. In the method of using the original image as the sub-image as is, the original image is used as is as the first sub-image. Furthermore, the original image is used as is as the second sub-image. When this method is used, it is not necessary to operate a circuit for newly creating a sub-image, or there is no need to use the circuit itself, so that it is possible to reduce power consumption and manufacturing costs. In particular, in a liquid crystal display device, the first
In step 3, it is preferable to use this method after performing frame rate conversion in which the intermediate image obtained by motion compensation is used as an interpolated image. This is because by using the intermediate image obtained by motion compensation as an interpolated image, it is possible to smooth the movement of the moving image while repeatedly displaying the same image, thereby reducing problems such as trailing and afterimages in the moving image caused by insufficient writing voltage due to the dynamic capacitance of the liquid crystal element.

Next, a detailed description will be given of a method for setting the brightness of an image and the length of the period during which the sub-images are displayed in a method for distributing the brightness of an original image to a plurality of sub-images. Note that J represents the number of sub-images and is an integer of 2 or more. The lowercase j is distinguished from the uppercase J. The integer j is 1 or more and J or less.
The pixel brightness in normal hold drive is L, the period of the original image data is T,
Let L _j be the brightness of a pixel in the jth sub-image, and T _j be the length of the period during which the jth sub-image is displayed. Then, the product of L _j and T _j is calculated, and the sum of these products from j=1 to j=J (L
It is preferable _that Lj _{( LT} ) is equal to the product of L and T (LT), i.e., brightness is constant. Furthermore, it is preferable that the sum of _Tj from j= ₁ to j _{= J ( Tj} ) is equal to T (the display cycle of the original image is maintained). Here, the condition that brightness is _constant and the display cycle of the original image is maintained is referred to as the sub-image distribution condition.

Among the methods of distributing the brightness of an original image to a plurality of sub-images, the black insertion method is a method in which at least one sub-image is a black image. This allows the display method to be a pseudo-impulse type, and thus prevents the quality of the moving image from deteriorating due to the display method being a hold type. Here, in order to prevent the brightness of the display image from decreasing due to the insertion of a black image, it is preferable to follow the sub-image distribution conditions. However, in a situation in which the decrease in brightness of the display image is acceptable (such as when the surroundings are dark), or in a case in which the user has set the display image to allow the decrease in brightness, the sub-image distribution conditions do not need to be followed. For example, one sub-image may be the same as the original image, and the other sub-image may be a black image. In this case, power consumption can be reduced compared to when the sub-image distribution conditions are followed. Furthermore, in a liquid crystal display device, when one sub-image is one in which the overall brightness of the original image is increased without limiting the maximum brightness, the brightness of the backlight may be increased to realize the sub-image distribution conditions. In this case, the sub-image distribution conditions can be satisfied without controlling the voltage value written to the pixel, so that the operation of the image processing circuit can be omitted and power consumption can be reduced.

The black insertion method is characterized in that in any one of the sub-images, _Lj of all pixels is set to 0. In this way, the display method can be made pseudo-impulse type, and therefore degradation of moving image quality caused by the display method being a hold type can be prevented.

Among the methods of distributing the brightness of an original image to multiple sub-images, the time-division grayscale control method divides the brightness of the original image into multiple ranges, and when controlling the brightness in each range, it is performed by using only one of all the sub-images. By doing so, the display method can be made pseudo-impulse type without reducing the brightness, and therefore it is possible to prevent the deterioration of the quality of the moving image caused by the display method being a hold type.

As a method for dividing the brightness of the original image into multiple ranges, the maximum brightness value (L _max ) is expressed as follows:
There is a method of dividing the image into as many sub-images as there are sub-images. For example, in a display device that can adjust the brightness from 0 to _Lmax in 256 steps (gradation 0 to gradation 255), if the number of sub-images is two, when displaying gradations 0 to 127, the brightness of one sub-image is adjusted in the range of gradations 0 to 255, while the brightness of the other sub-image is set to gradation 0.
When displaying gradations from 128 to 255, the brightness of one of the sub-images is set to gradation 255.
This is a method of adjusting the brightness of the other sub-image in the range of gradation 0 to gradation 255. This allows the human eye to perceive the original image as being displayed, and also allows a pseudo impulse type display, thereby preventing a decrease in video quality due to the hold type. The number of sub-images may be greater than two. For example, when the number of sub-images is three, the brightness levels of the original image (gradation 0 to gradation 255) are adjusted.
55) is divided into three. Note that, depending on the number of brightness levels in the original image and the number of sub-images, the number of brightness levels may not be divisible by the number of sub-images, but the number of brightness levels included in each brightness range after division does not have to be exactly the same, as long as they are appropriately allocated.

In addition, the time division gray scale control method is also preferable because, by satisfying the sub-image distribution conditions, a decrease in brightness does not occur and an image similar to the original image can be displayed.

Among the methods of distributing the brightness of an original image to multiple sub-images, the gamma complement method is a method in which one sub-image is a bright image obtained by modifying the gamma characteristics of the original image, and the other sub-image is a dark image obtained by modifying the gamma characteristics of the original image. This allows the display method to be pseudo-impulse type without reducing the brightness, thereby preventing the deterioration of video quality caused by the hold type display method. Here, the gamma characteristic refers to the degree of brightness relative to the brightness level (gradation). Usually, the gamma characteristic is adjusted to be close to linear. This is because smooth gradation can be obtained by making the change in brightness proportional to the gradation, which is the brightness level. In the gamma complement method, the gamma characteristic of one sub-image is shifted from linearity and adjusted to be brighter than linear in the area of intermediate brightness (midtone) (midtone becomes a brighter image than it should be).
The gamma characteristic of the other sub-image is also shifted from the linear characteristic, and adjusted so that it is darker than the linear characteristic in the midtone region (the midtones become darker than they should be). Here, the amount by which one sub-image is brighter than the linear characteristic and the amount by which the other sub-image is darker than the linear characteristic are calculated as follows:
It is preferable to make all gradations approximately equal. This allows the human eye to perceive the image as if it were the original image, and prevents degradation of moving image quality due to the hold type. The number of sub-images may be greater than two. For example, when the number of sub-images is three, the gamma characteristics of each of the three sub-images may be adjusted so that the total amount of brightening from linearity and the total amount of darkening from linearity are approximately equal.

In addition, the gamma complement method is also preferable because, by satisfying the sub-image distribution conditions, a decrease in brightness does not occur and an image similar to the original image can be displayed.
In the gamma complement method, the change in brightness _Lj of each sub-image with respect to the gradation follows a gamma curve, so that each sub-image can display the gradation smoothly by itself.
The final benefit is that the image quality as perceived by the human eye is also improved.

The method of using intermediate images obtained by motion compensation as sub-images is a method in which one of the sub-images is an intermediate image obtained by motion compensation from the previous and next images. This makes it possible to smooth the movement of the images, thereby improving the quality of the video.

Next, the relationship between the timing of displaying the sub-images and the method of creating the sub-images will be described. The timing of displaying the first sub-image is the same as the timing of displaying the original image determined in the first step, and the timing of displaying the second sub-image can be determined arbitrarily regardless of the timing of displaying the original image determined in the first step. However, the sub-image itself may be changed according to the timing of displaying the second sub-image. In this way, even if the timing of displaying the second sub-image is changed in various ways, the human eye can be made to perceive as if the original image was being displayed. Specifically, if the timing of displaying the second sub-image is made earlier, the first sub-image will be brighter and the second sub-image will be darker.
The first sub-image can be made darker. Furthermore, if the timing of displaying the second sub-image is delayed, the first sub-image can be made darker and the second sub-image can be made brighter. This is because the brightness perceived by the human eye varies depending on the length of the period in which the image is displayed. More specifically, the brightness perceived by the human eye becomes brighter the longer the period in which the image is displayed, and becomes darker the shorter the period in which the image is displayed. That is, by advancing the timing of displaying the second sub-image, the length of the period in which the first sub-image is displayed becomes shorter and the length of the period in which the second sub-image is displayed becomes longer, so that the first sub-image is perceived as dark and the second sub-image is perceived as bright by the human eye as it is. As a result, an image different from the original image is perceived by the human eye, but in order to prevent this, the first sub-image is adjusted to be displayed earlier than the first sub-image.
The first sub-image can be made brighter and the second sub-image can be made darker.
By delaying the timing of displaying the first sub-image, the length of the period for displaying the first sub-image becomes longer and the length of the period for displaying the second sub-image becomes shorter, so that the first sub-image can be made darker and the second sub-image can be made brighter.

Based on the above description, the processing procedure in the second step is as follows.
In step 1, a method for generating multiple sub-images from one original image is determined. More specifically, the method for generating multiple sub-images can be selected from a method in which the original image is used as the sub-image as is, a method in which the brightness of the original image is distributed to the multiple sub-images, and a method in which an intermediate image obtained by motion compensation is used as the sub-image.
In step 2, the number of sub-images J is determined, where J is an integer equal to or greater than 2.
In step 3, the brightness L _j of the pixel in the jth sub-image and the length T _j of the period during which the jth sub-image is displayed are determined according to the method selected in step 1. Through step 3, the length of the period during which each sub-image is displayed and the brightness of each pixel included in each sub-image are specifically determined.
In step 4, the original image is processed according to the items determined in steps 1 to 3, and is actually displayed.
In step 5, the target original image is moved to the next original image, and the process returns to step 1.

The mechanism for executing the procedure in the second step may be implemented in the device, or may be determined in advance at the design stage of the device. If the mechanism for executing the procedure in the second step is implemented in the device, it becomes possible to switch the driving method so that the optimum operation is performed according to the situation. The situation here refers to the contents of the image data, the environment inside and outside the device (temperature, humidity, air pressure, light, sound, magnetic field, electric field, radiation amount,
altitude, acceleration, moving speed, etc.), user settings, software version, etc. On the other hand, if the mechanism for executing the procedure in the second step is predetermined at the design stage of the device, it is possible to use a drive circuit optimal for each drive method, and further, since the mechanism is already determined, a reduction in manufacturing costs can be expected due to mass production economies.

Next, various driving methods determined by the procedure in the second step will be described in detail, with specific values of n and m in the first step.

In the procedure 1 in the second step, when the method of using the original image as the sub-image as it is is selected, the driving method is as follows.

The i-th (i is a positive integer) image data;
The (i+1)th image data is sequentially prepared at a constant period T,
The period T is divided into J sub-image display periods (J is an integer equal to or greater than 2),
The i-th image data is data that can give each of a plurality of pixels a unique brightness L,
The jth (j is an integer between 1 and J) sub-image is an image that is configured by arranging a plurality of pixels, each having a specific brightness _Lj , and is displayed only for the jth sub-image display period _Tj ,
A method for driving a display device in which the L, the T, the L _j , and the T _j satisfy a sub-image distribution condition,
The brightness _Lj of each pixel contained in the jth sub-image is characterized in that _Lj = L for each pixel, for all j.
Here, the original image data created in the first step can be used as the image data sequentially prepared at a constant cycle T. That is, all the display patterns described in the first step can be combined with the above driving method.

Then, in the procedure 2 in the second step, if the number J of sub-images is determined to be 2, and in the procedure 3, it is determined that T ₁ =T ₂ =T/2, the driving method will be as shown in FIG.
In FIG. 69, the horizontal axis represents time, and the vertical axis represents cases for various n and m used in the first step.

For example, in the first step, when n=1, m=1, that is, the conversion ratio (n/m) is 1, the driving method is as shown in the n=1, m=1 portion of FIG. 69. At this time, the display frame rate is twice the frame rate of the input image data (double speed drive). Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 120 Hz (120 Hz drive). Then, for one input image data, an image is displayed twice in succession. Here, in the case of double speed drive, the quality of the moving image can be improved compared to when the frame rate is lower than double speed, and power consumption and manufacturing costs can be reduced compared to when the frame rate is higher than double speed. Furthermore, in step 1 of the second step,
By selecting a method of using the original image as the sub-image as is, the operation of the circuit for creating an intermediate image by motion compensation can be stopped or the circuit itself can be omitted from the device, thereby reducing power consumption and the manufacturing costs of the device. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of insufficient write voltage due to dynamic capacitance can be avoided, resulting in a particularly significant improvement in image quality against problems such as trailing in moving images and afterimages. Furthermore, it is also effective to combine the AC drive of the liquid crystal display device with 120 Hz drive. That is, while setting the drive frequency of the liquid crystal display device to 120 Hz, the AC drive frequency can be set to an integer multiple or an integer fraction of that (for example, 30 Hz, 60 Hz,
By setting the frequency to a frequency of 100 Hz (120 Hz, 240 Hz, etc.), flicker caused by AC driving can be reduced to a level that is not perceptible to the human eye. Furthermore, by applying the present invention to a liquid crystal display device in which the response time of the liquid crystal element is about half the period of the input image data, the image quality can be improved.

Furthermore, for example, in the first step, n=2, m=1, i.e., the conversion ratio (n/m
) is 2, the driving method is as shown in the n=2, m=1 portion of FIG. 69. At this time, the display frame rate is four times the frame rate of the input image data (quadruple-speed drive). Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 240 Hz (240 Hz drive). Then, for one input image data, an image is displayed four times in succession. At this time, if the interpolated image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, so that the quality of the moving image can be significantly improved. Here, in the case of quadruple-speed drive, the quality of the moving image can be improved more than when the frame rate is lower than quadruple speed, and the power consumption and manufacturing cost can be reduced more than when the frame rate is higher than quadruple speed. Furthermore, in step 1 of the second step, a method of using the original image as it is as a sub-image is selected, so that the operation of the circuit that creates the intermediate image by motion compensation can be stopped or the circuit itself can be omitted from the device, so that the power consumption and manufacturing cost of the device can be reduced. Furthermore, in the case where the display device is an active matrix liquid crystal display device,
Since the problem of insufficient writing voltage due to dynamic capacitance can be avoided, it brings about a particularly remarkable effect of improving image quality against problems such as video tailing and afterimages. Furthermore, it is also effective to combine the AC drive and 240 Hz drive of a liquid crystal display device. That is, by setting the drive frequency of the liquid crystal display device to 240 Hz and setting the frequency of the AC drive to an integer multiple or an integer fraction of that frequency (for example, 30 Hz, 60 Hz, 120 Hz, 240 Hz, etc.), it is possible to reduce flicker caused by the AC drive to a level that is not perceptible to the human eye. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/4 the period of the input image data, it is possible to improve image quality.

Furthermore, for example, in the first step, n=3, m=1, i.e., the conversion ratio (n/m
) is 3, the driving method is as shown in the n=3, m=1 part of FIG. 69. At this time, the display frame rate is six times the frame rate of the input image data (six-times speed drive). Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 360 Hz (360 Hz drive). Then, for one input image data, an image is displayed six times in succession. At this time, if the interpolated image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, so that the quality of the moving image can be significantly improved. Here, in the case of six-times speed drive, the quality of the moving image can be improved more than when the frame rate is lower than six times speed, and the power consumption and manufacturing cost can be reduced more than when the frame rate is higher than six times speed. Furthermore, in step 1 of the second step, a method of using the original image as it is as a sub-image is selected, so that the operation of the circuit that creates the intermediate image by motion compensation can be stopped or the circuit itself can be omitted from the device, so that the power consumption and the manufacturing cost of the device can be reduced. Furthermore, in the case where the display device is an active matrix type liquid crystal display device,
Since the problem of insufficient writing voltage due to dynamic capacitance can be avoided, it brings about a particularly remarkable effect of improving image quality against problems such as video tailing and afterimages. Furthermore, it is also effective to combine the AC drive and 360 Hz drive of a liquid crystal display device. That is, by setting the drive frequency of the liquid crystal display device to 360 Hz and setting the frequency of the AC drive to an integer multiple or an integer fraction of that (for example, 30 Hz, 60 Hz, 120 Hz, 180 Hz, etc.), it is possible to reduce flicker caused by the AC drive to a level that is not perceptible to the human eye. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/6 the period of the input image data, it is possible to improve image quality.

Furthermore, for example, in the first step, n=3, m=2, i.e., the conversion ratio (n/m
) is 3/2, the driving method is as shown in the portion of FIG. 69 where n=3 and m=2.
At this time, the display frame rate is three times the frame rate of the input image data (triple speed drive). Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 180 Hz (180 Hz drive). For one input of image data, an image is displayed three times in succession. At this time, if the interpolated image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, and the quality of the moving image can be significantly improved. Here, 3
In the case of double-speed driving, the quality of the moving image can be improved compared to when the frame rate is lower than triple speed, and the power consumption and manufacturing cost can be reduced compared to when the frame rate is higher than triple speed. Furthermore, by selecting a method of using the original image as the sub-image as it is in step 1 of the second step, the operation of the circuit that creates the intermediate image by motion compensation can be stopped or the circuit itself can be omitted from the device, thereby reducing the power consumption and the manufacturing cost of the device. Furthermore, in the case where the display device is an active matrix liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, so that a particularly remarkable image quality improvement effect is brought about against obstacles such as trailing of moving images and afterimages. Furthermore, it is also effective to combine the AC drive and 180 Hz drive of the liquid crystal display device. That is, by setting the drive frequency of the liquid crystal display device to 180 Hz and setting the frequency of the AC drive to an integer multiple or an integer fraction of that (for example, 30 Hz, 60 Hz, 120 Hz, 180 Hz, etc.), the flicker that appears due to the AC drive can be reduced to a level that is not perceptible to the human eye. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/3 times the period of the input image data, the image quality can be improved.

Furthermore, for example, in the first step, n=4, m=1, i.e., the conversion ratio (n/m
) is 4, the driving method is as shown in the n=4, m=1 portion of FIG. 69. At this time, the display frame rate is 8 times the frame rate of the input image data (8x speed drive). Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 480 Hz (480 Hz drive). Then, for one input image data, an image is displayed 8 times in succession. At this time, if the interpolated image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, so that the quality of the moving image can be significantly improved. Here, in the case of 8x speed drive, the quality of the moving image can be improved more than when the frame rate is lower than 8x speed, and the power consumption and manufacturing cost can be reduced more than when the frame rate is higher than 8x speed. Furthermore, in step 1 of the second step, a method of using the original image as it is as a sub image is selected, so that the operation of the circuit that creates the intermediate image by motion compensation can be stopped or the circuit itself can be omitted from the device, so that the power consumption and manufacturing cost of the device can be reduced. Furthermore, in the case where the display device is an active matrix type liquid crystal display device,
Since the problem of insufficient writing voltage due to dynamic capacitance can be avoided, it brings about a particularly remarkable effect of improving image quality against problems such as video tailing and afterimages. Furthermore, it is also effective to combine the AC drive and 480 Hz drive of a liquid crystal display device. That is, by setting the drive frequency of the liquid crystal display device to 480 Hz and setting the AC drive frequency to an integer multiple or an integer fraction of that frequency (for example, 30 Hz, 60 Hz, 120 Hz, 240 Hz, etc.), it is possible to reduce flicker caused by the AC drive to a level that is not perceptible to the human eye. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/8 times the period of the input image data, it is possible to improve image quality.

Furthermore, for example, in the first step, n=4, m=3, i.e., the conversion ratio (n/m
) is 4/3, the driving method is as shown in the portion of FIG. 69 where n=4 and m=3.
At this time, the display frame rate is 8/3 times (8
8/3x speed drive). Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 160 Hz (160 Hz drive). Then, for three input image data, the image is displayed eight times in succession. At this time, if the interpolated image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, so that the quality of the moving image can be significantly improved. Here, in the case of 8/3x speed drive, the quality of the moving image can be improved more than when the frame rate is lower than 8/3x speed, and the power consumption and manufacturing cost can be reduced more than when the frame rate is higher than 8/3x speed. Furthermore, by selecting a method of using the original image as it is as a sub-image in step 1 of the second step, the operation of the circuit that creates the intermediate image by motion compensation can be stopped or the circuit itself can be omitted from the device, so that the power consumption and manufacturing cost of the device can be reduced. Furthermore, in the case where the display device is an active matrix liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, so that a particularly significant image quality improvement effect is brought about against obstacles such as trailing of moving images and afterimages.
Furthermore, it is also effective to combine the AC drive and 160 Hz drive of the liquid crystal display device. That is, by setting the drive frequency of the liquid crystal display device to 160 Hz and the frequency of the AC drive to an integer multiple or an integer fraction of that frequency (for example, 40 Hz, 80 Hz, 160 Hz, 320 Hz, etc.), it is possible to reduce the flicker caused by the AC drive to a level that is not perceptible to the human eye. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 3/8 times the period of the input image data, it is possible to improve the image quality.

Furthermore, for example, in the first step, n=5, m=1, i.e., the conversion ratio (n/m
) is 5, the driving method is as shown in the portion of FIG. 69 where n=5, m=1. In this case, the display frame rate is 10 times the frame rate of the input image data (10x speed drive). Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 600 Hz (600 Hz drive). For one input of image data, an image is displayed 10 times in succession. In this case, if the interpolated image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, and the quality of the moving image can be significantly improved. Here,
In the case of 10x speed drive, the quality of the moving image can be improved compared to when the frame rate is lower than 10x speed, and the power consumption and manufacturing cost can be reduced compared to when the frame rate is higher than 10x speed. Furthermore, by selecting the method of using the original image as the sub-image as it is in step 1 of the second step, the operation of the circuit that creates the intermediate image by motion compensation can be stopped or the circuit itself can be omitted from the device, so that the power consumption and manufacturing cost of the device can be reduced. Furthermore, in the case where the display device is an active matrix type liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, so that a particularly remarkable image quality improvement effect is brought about against obstacles such as trailing of moving images and afterimages. Furthermore, it is also effective to combine the AC drive and 600 Hz drive of the liquid crystal display device. That is, by setting the drive frequency of the liquid crystal display device to 600 Hz and setting the frequency of the AC drive to an integer multiple or an integer fraction of that (for example, 30 Hz, 60 Hz, 100 Hz, 120 Hz, etc.), the flicker that appears due to the AC drive can be reduced to a level that is not perceptible to the human eye. Furthermore, by applying the present invention to a liquid crystal display device in which the response time of the liquid crystal element is about 1/10 times the period of the input image data, the image quality can be improved.

Furthermore, for example, in the first step, n=5, m=2, i.e., the conversion ratio (n/m
) is 5/2, the driving method is as shown in the portion of FIG. 69 where n=5 and m=2.
At this time, the display frame rate is five times the frame rate of the input image data (5x speed drive). Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 300 Hz (300 Hz drive). Then, for one input image data, an image is displayed five times in succession. At this time, if the interpolated image in the first step is an intermediate image obtained by motion compensation, the movement of the moving image can be made smooth, so that the quality of the moving image can be significantly improved. Here, in the case of 5x speed drive, the quality of the moving image can be improved more than when the frame rate is lower than 5x speed, and power consumption and manufacturing costs can be reduced more than when the frame rate is higher than 5x speed. Furthermore, in the case of the second
By selecting a method of using the original image as the sub-image as it is in procedure 1 of step 1, the operation of the circuit that creates the intermediate image by motion compensation can be stopped or the circuit itself can be omitted from the device, thereby reducing power consumption and the manufacturing costs of the device. Furthermore, if the display device is an active matrix liquid crystal display device, the problem of insufficient write voltage due to dynamic capacitance can be avoided, resulting in a particularly significant improvement in image quality against problems such as trailing in moving images and afterimages. Furthermore, it is also effective to combine AC driving of the liquid crystal display device with 300 Hz driving. That is, while setting the driving frequency of the liquid crystal display device to 300 Hz, the AC driving frequency can be set to an integer multiple or an integer fraction of that (
For example, by setting the frequency to 30 Hz, 50 Hz, 60 Hz, 100 Hz, etc., flicker caused by AC driving can be reduced to a level that is not perceptible to the human eye. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about 1/5 the period of the input image data, the image quality can be improved.

In this way, in step 1 of the second step, the method of using the original image as the sub-image as it is is selected,
In step 2 of the second step, the number of sub-images is determined to be 2;
In step 3 of the second step, if it is determined that T1=T2=T/2,
Since the display frame rate can be doubled for the frame rate conversion with the conversion ratio determined by the values of n and m in step 1, the quality of the moving image can be further improved. Furthermore, the quality of the moving image can be improved compared to a case where the display frame rate is lower than the display frame rate, and power consumption and manufacturing costs can be reduced compared to a case where the display frame rate is higher than the display frame rate.
Furthermore, by selecting the method of using the original image as the sub-image as is in procedure 1 of the second step, the operation of the circuit that creates the intermediate image by motion compensation can be stopped or the circuit itself can be omitted from the device, thereby reducing power consumption and the manufacturing costs of the device. Furthermore, if the display device is an active matrix liquid crystal display device, the problem of insufficient write voltage caused by dynamic capacitance can be avoided, resulting in a particularly significant improvement in image quality against problems such as trailing in moving images and afterimages. Furthermore,
By increasing the driving frequency of the liquid crystal display device and setting the frequency of the AC driving to an integer multiple or an integer fraction of that frequency, it is possible to reduce flicker caused by the AC driving to a level that is not perceptible to the human eye. Furthermore, the response time of the liquid crystal element is reduced to a period of the input image data (
By applying this to a liquid crystal display device with a conversion ratio of about 1/(twice the conversion ratio), the image quality can be improved.

Although detailed explanations are omitted, it is clear that the same advantages are obtained even in cases other than the above-mentioned conversion ratios. For example, when n is in the range of 10 or less, in addition to the above,
n = 5, m = 3, i.e., conversion ratio (n/m) = 5/3 (10/3x speed drive, 200Hz)
,
n = 5, m = 4, i.e., conversion ratio (n/m) = 5/4 (5/2x speed drive, 150Hz),
n = 6, m = 1, i.e., conversion ratio (n/m) = 6 (12x speed drive, 720Hz),
n = 6, m = 5, i.e., conversion ratio (n/m) = 6/5 (12/5x speed drive, 144Hz)
,
n = 7, m = 1, i.e., conversion ratio (n/m) = 7 (14x speed drive, 840Hz),
n = 7, m = 2, i.e., conversion ratio (n/m) = 7/2 (7x speed drive, 420Hz),
n = 7, m = 3, i.e., conversion ratio (n/m) = 7/3 (14/3x speed drive, 280Hz)
,
n = 7, m = 4, i.e., conversion ratio (n/m) = 7/4 (7/2x speed drive, 210Hz),
n = 7, m = 5, i.e., conversion ratio (n/m) = 7/5 (14/5x speed drive, 168Hz)
,
n = 7, m = 6, i.e., conversion ratio (n/m) = 7/6 (7/3x speed drive, 140Hz),
n = 8, m = 1, i.e., conversion ratio (n/m) = 8 (16x speed drive, 960Hz),
n = 8, m = 3, i.e., conversion ratio (n/m) = 8/3 (16/3x speed drive, 320Hz)
,
n = 8, m = 5, i.e., conversion ratio (n/m) = 8/5 (16/5x speed drive, 192Hz)
,
n = 8, m = 7, i.e., conversion ratio (n/m) = 8/7 (16/7x speed drive, 137Hz)
,
n = 9, m = 1, i.e., conversion ratio (n/m) = 9 (18x speed drive, 1080Hz),
n = 9, m = 2, i.e., conversion ratio (n/m) = 9/2 (9x speed drive, 540Hz),
n = 9, m = 4, i.e., conversion ratio (n/m) = 9/4 (9/2x speed drive, 270Hz),
n = 9, m = 5, i.e., conversion ratio (n/m) = 9/5 (18/5x speed drive, 216Hz)
,
n = 9, m = 7, i.e., conversion ratio (n/m) = 9/7 (18/7x speed drive, 154Hz)
,
n = 9, m = 8, i.e., conversion ratio (n/m) = 9/8 (9/4x speed drive, 135Hz),
n = 10, m = 1, i.e., conversion ratio (n/m) = 10 (20x speed drive, 1200 Hz),
n = 10, m = 3, that is, conversion ratio (n/m) = 10/3 (20/3x speed drive, 400H
z),
n = 10, m = 7, that is, conversion ratio (n/m) = 10/7 (20/7x speed drive, 171H
z),
n = 10, m = 9, that is, conversion ratio (n/m) = 10/9 (20/9x speed drive, 133H
z),
The above combinations are possible. Note that the frequency notation is an example when the input frame rate is 60 Hz, and for other input frame rates, the driving frequency is the product of the input frame rate and twice the respective conversion ratio.

In addition, in the case where n is an integer greater than 10, no specific values of n and m are given, but it is clear that the procedure in the second step can be applied to various values of n and m.

In addition, when J=2, it is particularly effective if the conversion ratio in the first step is greater than 2. This is because, if the number of sub-images in the second step is relatively small, such as J=2, the conversion ratio in the first step can be increased accordingly. Such conversion ratios are 3, 4, 5, 5/2, 6, 7, etc., when n is in the range of 10 or less.
, 7/2, 7/3, 8, 8/3, 9, 9/2, 9/4, 10, and 10/3.
When the display frame rate after the first step is such a value, by setting J = 3 or more, it is possible to achieve both the advantages of having a small number of sub-images in the second step (reduced power consumption and manufacturing costs, etc.) and the advantages of having a high final display frame rate (improved video quality, reduced flicker, etc.).

In this case, the number of sub-images J is determined to be 2 in step 2, and T ₁ =
Although the case where T ₂ =T/2 has been described, it is clear that the present invention is not limited to this.

For example, if it is determined in step 3 in the second step that T ₁ <T ₂ , the first sub-image can be made brighter and the second sub-image can be made darker.
In step 3 of the above step, if it is determined that _T1 > _T2 , the first sub-image can be made darker and the second sub-image can be made brighter. In this way, the original image can be properly perceived by the human eye, and at the same time, the display can be pseudo-impulse driven, improving the quality of the moving image. However, as in the above driving method, if a method is selected in step 1 in which the original image is used as the sub-image as is, the sub-image may be displayed as is without changing its brightness. This is because, in this case, the same image is used as the sub-image, and the original image can be properly displayed regardless of the display timing of the sub-image.

Furthermore, in step 2, it is clear that the number J of sub-images may be determined to be a value other than 2. In this case, the display frame rate can be set to a frame rate that is J times higher than the frame rate conversion with a conversion ratio determined by the values of n and m in the first step, so that the quality of the moving image can be further improved. Furthermore, the quality of the moving image can be improved compared to a display frame rate lower than the display frame rate, and the power consumption and manufacturing cost can be reduced compared to a display frame rate higher than the display frame rate. Furthermore, by selecting a method of using the original image as a sub-image as it is in step 1 of the second step, the operation of a circuit that creates an intermediate image by motion compensation can be stopped or the circuit itself can be omitted from the device, so that the power consumption and manufacturing cost of the device can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, resulting in a particularly significant image quality improvement effect against problems such as trailing of moving images and afterimages. Furthermore, by increasing the driving frequency of the liquid crystal display device and setting the frequency of the AC driving to an integer multiple or an integer fraction of the frequency, the flicker that appears due to the AC driving can be reduced to a level that is not noticeable to the human eye. Furthermore, by applying this invention to a liquid crystal display device in which the response time of the liquid crystal element is approximately (1/(J times the conversion ratio)) times the period of the input image data, the image quality can be improved.

For example, when J=3, there is an advantage that the quality of the moving image can be improved compared to when the number of sub-images is less than 3, and the power consumption and manufacturing cost can be reduced compared to when the number of sub-images is more than 3. Furthermore, the response time of the liquid crystal element is 1/2 the period of the input image data.
By applying this to a liquid crystal display device having a conversion ratio of about 3 times, the image quality can be improved.

Furthermore, for example, when J=4, there is an advantage that the quality of moving images can be improved compared to when the number of sub-images is smaller than 4, and power consumption and manufacturing costs can be reduced compared to when the number of sub-images is greater than 4. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about (1/(4 times the conversion ratio)) times the period of the input image data, the image quality can be improved.

Furthermore, for example, when J=5, there is an advantage that the quality of moving images can be improved compared to when the number of sub-images is smaller than 5, and power consumption and manufacturing costs can be reduced compared to when the number of sub-images is greater than 5. Furthermore, by applying this to a liquid crystal display device in which the response time of the liquid crystal element is about (1/(5 times the conversion ratio)) times the period of the input image data, the image quality can be improved.

Furthermore, even if J is something other than those listed above, it has the same advantages.

In addition, when J=3 or more, the conversion ratio in the first step can take various values. In particular, when the conversion ratio in the first step is relatively small (2 or less), J=3
It is effective to set the conversion ratio to 1, 2, 3/2, 4/3, or more, because if the display frame rate after the first step is relatively small, J can be increased accordingly in the second step.
5/3, 5/4, 6/5, 7/4, 7/5, 7/6, 8/7, 9/5, 9/7, 9/8,
Among these, the conversion ratios are 1, 2, 3/2, 4/3, 5/
The cases of 3 and 5/4 are shown in Fig. 70. In this way, when the display frame rate after the first step is a relatively small value, by setting J to 3 or more, it is possible to achieve both the advantages of a small display frame rate in the first step (reduced power consumption and manufacturing costs, etc.) and the advantages of a high final display frame rate (improved video quality, reduced flicker, etc.).

Next, another example of the driving method determined by the procedure in the second step will be described.

In the procedure 1 in the second step, when the black insertion method is selected from among the methods for distributing the brightness of the original image to a plurality of sub-images, the driving method is as follows.

The i-th (i is a positive integer) image data;
The (i+1)th image data is sequentially prepared at a constant period T,
The period T is divided into J sub-image display periods (J is an integer equal to or greater than 2),
The i-th image data is data that can give each of a plurality of pixels a unique brightness L,
The jth (j is an integer between 1 and J) sub-image is an image that is configured by arranging a plurality of pixels, each having a specific brightness _Lj , and is displayed only for the jth sub-image display period _Tj ,
A method for driving a display device in which the L, the T, the L _j , and the T _j satisfy a sub-image distribution condition,
For at least one j, the brightness L _j of all pixels included in the j-th sub-image is L _j
= 0.
Here, the original image data created in the first step can be used as the image data sequentially prepared at a constant cycle T. That is, all the display patterns described in the first step can be combined with the above driving method.

It is apparent that the above driving method can be carried out in combination with various values of n and m used in the first step.

Then, in the procedure 2 in the second step, if the number J of sub-images is determined to be 2, and in the procedure 3, it is determined that T ₁ =T ₂ =T/2, then the driving method will be as shown in FIG.
The features and advantages of the driving method shown in FIG. 69 (display timing at various n and m) have already been described, so a detailed description will be omitted here. However, it is clear that the same advantages are obtained when the black insertion method is selected from among the methods of distributing the brightness of the original image to a plurality of sub-images in step 1 of the second step. For example, when the interpolated image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, so that the quality of the moving image can be significantly improved. Furthermore, when the display frame rate is high, the quality of the moving image can be improved, and when the display frame rate is low, the power consumption and manufacturing cost can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, so that a particularly significant image quality improvement effect is brought about against obstacles such as trailing of moving images and afterimages. Furthermore, the flicker caused by AC driving can be reduced to a level that is not perceptible to the human eye.

In step 1 of the second step, among the methods for distributing the brightness of the original image to multiple sub-images, the black insertion method is selected as a distinctive advantage because it allows the operation of the circuit that creates intermediate images by motion compensation to be stopped or the circuit itself to be omitted from the device.
It is possible to reduce power consumption and manufacturing costs of the device. Furthermore, since a pseudo impulse type display method can be achieved regardless of the gradation values contained in the image data, the quality of moving images can be improved.

In this case, the number of sub-images J is determined to be 2 in step 2, and T ₁ =
Although the case where T ₂ =T/2 has been described, it is clear that the present invention is not limited to this.

For example, if it is determined in step 3 in the second step that T ₁ <T ₂ , the first sub-image can be made brighter and the second sub-image can be made darker.
If it is determined in step 3 that _T1 > _T2 , the first sub-image can be made darker and the second sub-image can be made brighter. In this way, the original image can be properly perceived by the human eye, and at the same time, the display can be pseudo-impulse driven, improving the quality of the moving image. However, as in the above driving method, if the black insertion method is selected in step 1 from among the methods of distributing the brightness of the original image to multiple sub-images, the brightness of the sub-images may be left unchanged and displayed as is. This is because,
In this case, if the brightness of the sub-image is not changed, the original image will simply be displayed with a darker overall brightness. In other words, by actively using this method to control the brightness of a display device, it is possible to control the brightness while improving the quality of the moving image.

Furthermore, it is clear that in step 2, the number J of sub-images may be determined to be a value other than 2. The advantages of this case have already been described, so a detailed explanation will be omitted here, but it is clear that there are similar advantages when the black insertion method is selected from among the methods of distributing the brightness of the original image to multiple sub-images in step 1 of the second step. For example, if the response time of a liquid crystal element is (1/(J times the conversion ratio)) the period of the input image data,
By applying this to a liquid crystal display device, which has a resolution of about 1000x1000, the image quality can be improved.

Next, another example of the driving method determined by the procedure in the second step will be described.

In the procedure 1 of the second step, when the time division gray scale control method is selected from among the methods for distributing the brightness of the original image to a plurality of sub-images, the driving method is as follows.

The i-th (i is a positive integer) image data;
The (i+1)th image data is sequentially prepared at a constant period T,
The period T is divided into J sub-image display periods (J is an integer equal to or greater than 2),
The i-th image data is data that can give each of a plurality of pixels a unique brightness L,
The inherent brightness L has a maximum value L _max ,
The jth (j is an integer between 1 and J) sub-image is an image that is configured by arranging a plurality of pixels, each having a specific brightness _Lj , and is displayed only for the jth sub-image display period _Tj ,
A method for driving a display device in which the L, the T, the L _j , and the T _j satisfy a sub-image distribution condition,
In displaying the inherent brightness L, (j-1)×L _max /J to J×L _max
The brightness adjustment in the brightness range of /J is performed by adjusting the brightness in only one sub-image display period among the J sub-image display periods.
Here, the original image data created in the first step can be used as the image data sequentially prepared at a constant cycle T. That is, all the display patterns described in the first step can be combined with the above driving method.

It is apparent that the above driving method can be carried out in combination with various values of n and m used in the first step.

Then, in the procedure 2 in the second step, if the number J of sub-images is determined to be 2, and in the procedure 3, it is determined that T ₁ =T ₂ =T/2, the driving method will be as shown in FIG.
The features and advantages of the driving method shown in FIG. 69 (display timings at various n and m) have already been described, so a detailed description will be omitted here. However, it is clear that the same advantages are obtained when the time-division grayscale control method is selected from among the methods of distributing the brightness of the original image to a plurality of sub-images in step 1 of the second step. For example, when the interpolated image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, so that the quality of the moving image can be significantly improved. Furthermore, when the display frame rate is high, the quality of the moving image can be improved, and when the display frame rate is low, the power consumption and manufacturing cost can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, so that a particularly significant image quality improvement effect is brought about against obstacles such as trailing of moving images and afterimages. Furthermore, the flicker caused by AC driving can be reduced to a level that is not perceptible to the human eye.

Among the methods for distributing the brightness of the original image to a plurality of sub-images in procedure 1 of the second step, the time-division gray scale control method is selected, which has a distinctive advantage in that the operation of the circuit for creating intermediate images by motion compensation can be stopped or the circuit itself can be omitted from the device, thereby reducing power consumption and the manufacturing costs of the device.
Since a pseudo-impulse type display method can be used, the quality of moving images can be improved, and since the brightness of the display device is not reduced, power consumption can be further reduced.

In this case, the number of sub-images J is determined to be 2 in step 2, and T ₁ =
Although the case where T ₂ =T/2 has been described, it is clear that the present invention is not limited to this.

For example, if it is determined in step 3 in the second step that T ₁ <T ₂ , the first sub-image can be made brighter and the second sub-image can be made darker.
In the step 3, if it is determined that _T1 > _T2 , the first sub-image can be made darker and the second sub-image can be made brighter. In this way, the original image can be properly perceived by the human eye, and at the same time, the display can be pseudo-impulse driven, thereby improving the quality of the moving image. In this way, the original image can be properly perceived by the human eye, and at the same time, the display can be pseudo-impulse driven, thereby improving the quality of the moving image.

Furthermore, it is clear that in step 2, the number J of sub-images may be determined to be a value other than 2. Since the advantages of this case have already been described, detailed explanation will be omitted here, but it is clear that the same advantages are obtained when the time-division grayscale control method is selected from among the methods of distributing the brightness of the original image to a plurality of sub-images in step 1 of the second step. For example, image quality can be improved by applying this to a liquid crystal display device in which the response time of the liquid crystal element is approximately (1/(J times the conversion ratio)) times the period of the input image data.

Next, another example of the driving method determined by the procedure in the second step will be described.

In the procedure 1 of the second step, when the gamma complement method is selected from among the methods for distributing the brightness of the original image to a plurality of sub-images, the driving method is as follows.

The i-th (i is a positive integer) image data;
The (i+1)th image data is sequentially prepared at a constant period T,
The period T is divided into J sub-image display periods (J is an integer equal to or greater than 2),
The i-th image data is data that can give each of a plurality of pixels a unique brightness L,
The jth (j is an integer between 1 and J) sub-image is an image that is configured by arranging a plurality of pixels, each having a specific brightness _Lj , and is displayed only for the jth sub-image display period _Tj ,
A method for driving a display device in which the L, the T, the L _j , and the T _j satisfy a sub-image distribution condition,
In each sub-image, the characteristic of the change in brightness with respect to the gradation is shifted from linearity, and the sum of the brightness amounts shifted from the linearity to the brighter side and the sum of the brightness amounts shifted from the linearity to the darker side are approximately equal for all gradations.
Here, the original image data created in the first step can be used as the image data sequentially prepared at a constant cycle T. That is, all the display patterns described in the first step can be combined with the above driving method.

It is apparent that the above driving method can be carried out in combination with various values of n and m used in the first step.

Then, in the procedure 2 in the second step, if the number J of sub-images is determined to be 2, and in the procedure 3, it is determined that T ₁ =T ₂ =T/2, the driving method will be as shown in FIG.
The features and advantages of the driving method shown in FIG. 69 (display timings at various n and m) have already been described, so a detailed description will be omitted here. However, it is clear that the same advantages are obtained when the gamma complement method is selected from among the methods for distributing the brightness of the original image to a plurality of sub-images in step 1 of the second step. For example, when the interpolated image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be made smooth, so that the quality of the moving image can be significantly improved. Furthermore, when the display frame rate is high, the quality of the moving image can be improved, and when the display frame rate is low, the power consumption and manufacturing cost can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of insufficient writing voltage due to dynamic capacitance can be avoided, so that a particularly significant image quality improvement effect is brought about against obstacles such as trailing of moving images and afterimages. Furthermore, the flicker caused by AC driving can be reduced to a level that is not perceptible to the human eye.

Among the methods of distributing the brightness of the original image to a plurality of sub-images in the procedure 1 of the second step, the characteristic advantage of selecting the gamma complement method is that the operation of the circuit that creates the intermediate image by motion compensation can be stopped or the circuit itself can be omitted from the device, thereby reducing power consumption and the manufacturing cost of the device. Furthermore, since it is possible to make it a pseudo-impulse type display method regardless of the gradation value contained in the image data, the quality of the moving image can be improved. Furthermore, the sub-image may be obtained by directly gamma converting the image data. In this case, there is an advantage that the gamma value can be controlled in various ways depending on the magnitude of the moving image. Furthermore, the image data may not be directly gamma converted, but the reference voltage of the digital-to-analog conversion circuit (DAC) may be changed to obtain a sub-image with a changed gamma value. In this case, since the image data is not directly gamma converted, the circuit that performs the gamma conversion can be stopped or the circuit itself can be omitted from the device, thereby reducing power consumption and the manufacturing cost of the device. Furthermore, in the gamma complement method, since the change in brightness _Lj of each sub-image relative to the gradation follows a gamma curve, each sub-image can display a smooth gradation by itself, which has the advantage that the quality of the image perceived by the human eye is ultimately improved.

In this case, the number of sub-images J is determined to be 2 in step 2, and T ₁ =
Although the case where T ₂ =T/2 has been described, it is clear that the present invention is not limited to this.

For example, if it is determined in step 3 in the second step that T ₁ <T ₂ , the first sub-image can be made brighter and the second sub-image can be made darker.
In the step 3 of the above-mentioned driving method, if it is determined that _T1 > _T2 , the first sub-image can be made darker and the second sub-image can be made brighter. In this way, the original image can be properly perceived by the human eye, and at the same time, the display can be pseudo-impulse driven, improving the quality of the moving image.
In the above, when the gamma method is selected from among the methods of distributing the brightness of the original image to a plurality of sub-images, the gamma value may be changed when changing the brightness of the sub-images. That is, the gamma value may be determined according to the display timing of the second sub-image. In this way, the circuit that changes the brightness of the entire image can be stopped or the circuit itself can be omitted from the device, thereby reducing power consumption and the manufacturing cost of the device.

Furthermore, it is clear that in step 2, the number J of sub-images may be determined to be a value other than 2. Since the advantages of this case have already been described, detailed explanation will be omitted here, but it is clear that the same advantages are obtained when the time-division grayscale control method is selected from among the methods of distributing the brightness of the original image to a plurality of sub-images in step 1 of the second step. For example, image quality can be improved by applying this to a liquid crystal display device in which the response time of the liquid crystal element is approximately (1/(J times the conversion ratio)) times the period of the input image data.

Next, another example of the driving method determined by the procedure in the second step will be described in detail.

In step 1 of the second step, a method of using an intermediate image obtained by motion compensation as a sub-image is selected;
In step 2 of the second step, the number of sub-images is determined to be 2;
In step 3 of the second step, if it is determined that T1=T2=T/2,
The driving method determined by the procedure in step 3 is as follows.

The i-th (i is a positive integer) image data;
The (i+1)th image data is sequentially prepared at a constant period T,
A kth image (k is a positive integer),
The k+1th image;
A method for driving a display device that sequentially displays an image (k+2) and an image (k+3) at an interval that is 1/2 the period of the original image data, comprising:
The kth image is displayed according to the ith image data;
The k+1 image is displayed according to image data corresponding to a movement obtained by multiplying by half the movement from the i image data to the i+1 image data;
The k+2th image is displayed according to the i+1th image data.
Here, the original image data created in the first step can be used as the image data sequentially prepared at a constant cycle T. That is, all the display patterns described in the first step can be combined with the above driving method.

It is apparent that the above driving method can be carried out in combination with various values of n and m used in the first step.

A distinctive advantage of selecting the method of using the intermediate image obtained by motion compensation as the sub-image in procedure 1 of the second step is that when the intermediate image obtained by motion compensation is used as an interpolated image in the procedure of the first step, the method of obtaining the intermediate image used in the first step can be used in the second step as it is. In other words, the circuit for obtaining the intermediate image by motion compensation can be used not only in the first step but also in the second step, so that the circuit can be used effectively and processing efficiency can be improved. In addition, image motion can be made smoother, so that the quality of the moving image can be further improved.

In this case, the number of sub-images J is determined to be 2 in step 2, and T ₁ =
Although the case where T ₂ =T/2 has been described, it is clear that the present invention is not limited to this.

For example, if it is determined in step 3 in the second step that T ₁ <T ₂ , the first sub-image can be made brighter and the second sub-image can be made darker.
If it is determined in step 3 of step 1 that _T1 > _T2 , the first sub-image can be made darker and the second sub-image can be made brighter. In this way, the original image can be properly perceived by the human eye, and at the same time, the display can be pseudo-impulse driven, improving the quality of the moving image. In this way, the original image can be properly perceived by the human eye, and at the same time, the display can be pseudo-impulse driven, improving the quality of the moving image. Note that, as in the above driving method, in step 2,
When the method of using the intermediate image obtained by motion compensation as the sub-image is selected, the brightness of the sub-image does not need to be changed. This is because the intermediate image is complete in itself, so even if the display timing of the second sub-image changes, the image perceived by the human eye does not change. In this case, the circuit that changes the brightness of the entire image can be stopped or the circuit itself can be omitted from the device, thereby reducing power consumption and the manufacturing cost of the device.

Furthermore, it is clear that in step 2, the number J of sub-images may be determined to be a value other than 2. Since the advantages of this case have already been described, detailed explanation will be omitted here, but it is clear that the same advantages are obtained when a method of using intermediate images obtained by motion compensation as sub-images is selected in step 1 of the second step. For example, image quality can be improved by applying this method to a liquid crystal display device in which the response time of the liquid crystal elements is approximately (1/(J times the conversion ratio)) times the period of the input image data.

Next, a specific example of a frame rate conversion method when the input frame rate and the display frame rate are different will be described with reference to Fig. 71. In the method shown in Fig. 71 (A) to (C), a circular area on an image is an area whose position changes from frame to frame, and a triangular area on an image is an area whose position hardly changes from frame to frame. However,
This is an example for the purpose of explanation, and the image to be displayed is not limited to this. The methods of Fig. 71 (A) to (C) can be applied to various images.

FIG. 71(A) shows a case where the display frame rate is twice the input frame rate (conversion ratio is 2). A conversion ratio of 2 has the advantage of being able to improve the quality of moving images compared to a conversion ratio smaller than 2. Furthermore, a conversion ratio of 2 has the advantage of being able to reduce power consumption and manufacturing costs compared to a conversion ratio larger than 2.
1A) is a schematic diagram showing the temporal change of a displayed image, with the horizontal axis being time. Here, the image of interest is represented as the pth image (p is a positive integer). The image displayed next to the image of interest is represented as the (p+1)th image,
For convenience, an image displayed before an image of interest will be referred to as the (p-1)th image, indicating how far away it is from the image of interest. Image 180701 is the pth image, image 180702 is the (p+1)th image, image 180703 is the (p+2)th image, image 180704 is the (p+3)th image, image 180705 is the (p-6)th image, image 180706 is the (p-7)th image, image 180707 is the (p-8)th image, image 180708 is the (p-9)th image, image 180709 is the (p-1)th image, image 180710 is the (p-1)th image, image 180711 is the (p-2)th image, image 180712 is the (p-3)th image, image 1807
80705 is the (p+4)th image. The period Tin represents the cycle of the input image data. Note that FIG. 71A shows a case where the conversion ratio is 2, so the period Tin
is twice as long as the period from when the pth image is displayed to when the (p+1)th image is displayed.

Here, the (p+1)th image 180702 is obtained by subtracting the pth image 180701 from the (p+2)th image 180702.
71A, the intermediate state of the image is represented by a region (circular region) whose position changes from frame to frame, and a region (triangular region) whose position does not change much from frame to frame. That is, the position of the circular region in the (p+1)th image 180702 is set to an intermediate position between the position in the pth image 180701 and the position in the (p+2)th image 180703. That is, the (p+1)th image 180702 is obtained by performing motion compensation and interpolating image data. In this way, a smooth display can be achieved by performing motion compensation on an object moving on the image and interpolating image data.

Furthermore, the (p+1)th image 180702 is a combination of the pth image 180701 and the (p+2
Alternatively, the image may be created so as to be an intermediate state between the pth image 180701 and the (p+1)th image 180703, and the brightness of the image may be controlled according to a certain rule. For example, the certain rule may be that, as shown in FIG. 71A, when the representative brightness of the pth image 180701 is L and the representative brightness of the (p+1)th image 180702 is Lc, there is a relationship between L and Lc such that L>Lc.
The relationship may be 0.1L<Lc<0.8L. More preferably, the relationship is 0.2L<Lc.
There may be a relationship of c<0.5L. Alternatively, conversely, there may be a relationship of L<Lc between L and Lc. Desirably, there may be a relationship of 0.1Lc<L<0.8Lc.
More preferably, the relationship may be 0.2Lc<L<0.5Lc. In this way, the display can be made pseudo-impulse type, so that afterimages in the eyes can be suppressed.

The typical brightness of an image will be described in detail later with reference to Figure 72.

In this way, there are two different causes of video blur: image motion is not smooth,
By simultaneously solving the problems of blurring (image lag and eye retention), motion blur can be significantly reduced.

Furthermore, for the (p+3)th image 180704, the (p+2)th image 180703
The (p+3)th image 180704 may be created from the (p+2)th image 180703 and the (p+4)th image 180705 in a similar manner.
By detecting the amount of change in the images from the (p+2)th image 180705 to the (p+4)th image 180705,
It may be an image created so as to be in an intermediate state between the (p+4)th image 180703 and the (p+4)th image 180705, and further, an image in which the brightness of the image is controlled according to a certain rule.

Fig. 71B shows a case where the display frame rate is three times the input frame rate (the conversion ratio is 3). Fig. 71B shows a schematic diagram of the temporal change of the displayed image, with the horizontal axis representing time. Image 180711 is the pth image, image 1807
12 is the (p+1)th image, image 180713 is the (p+2)th image, and image 180714 is the (p+2)th image.
Assume that image 180715 is the (p+4)th image, image 180716 is the (p+5)th image, and image 180717 is the (p+6)th image. Period Tin represents the cycle of the input image data. Note that since Fig. 71(B) represents a case where the conversion ratio is 3, period Tin is three times as long as the period from when the pth image is displayed to when the (p+1)th image is displayed.

Here, the (p+1)th image 180712 and the (p+2)th image 180713 may be images created to be in an intermediate state between the pth image 180711 and the (p+3)th image 180714 by detecting the amount of change in the images from the pth image 180711 to the (p+3)th image 180714. In FIG. 71(B), the intermediate state image is represented by a region (circular region) whose position changes depending on the frame and a region (triangular region) whose position does not change much depending on the frame. That is, the position of the circular region in the (p+1)th image 180712 and the (p+2)th image 180713 is set to be an intermediate position between the position in the pth image 180711 and the position in the (p+3)th image 180714. Specifically, when the amount of movement of the circular area detected from the pth image 180711 and the (p+3)th image 180714 is X, the position of the circular area in the (p+1)th image 180712 may be displaced by about (1/3)X from its position in the pth image 180711.
The position of the circular area in 13 is calculated by (2/3
)X. In other words, the (p+1)th image 180712 and the (p+2)th image 180713 are obtained by performing motion compensation and interpolating image data. In this way, a smooth display can be achieved by performing motion compensation on a moving object on an image and interpolating image data.

Furthermore, the (p+1)th image 180712 and the (p+2)th image 180713 may be images created to be intermediate between the pth image 180711 and the (p+3)th image 180714, and the brightness of the images may be controlled according to a certain rule. The certain rule may be, for example, as shown in FIG. 71B, where the representative brightness of the pth image 180711 is L, the representative brightness of the (p+3)th image 180714 is L, and the representative brightness of the (p+4)th image 180714 is L.
The representative luminance of the (p+1)th image 180712 is Lc1, and the representative luminance of the (p+2)th image 180713 is Lc2.
When the representative luminance is Lc2, L, Lc1, and Lc2, L>Lc1 or L
>Lc2 or Lc1=Lc2. Preferably, 0.1L<Lc
The relationship may be 1=Lc2<0.8L. More preferably, the relationship is 0.2L<Lc=
There may be a relationship of Lc2<0.5L. Alternatively, conversely, there may be a relationship of L<Lc1, L<Lc2, or Lc1=Lc2 among L, Lc1, and Lc2. Desirably, there may be a relationship of 0.1Lc1=0.1Lc2<L<0.8Lc1=0.8Lc2. More desirably, there may be a relationship of 0.2Lc1=0.2Lc2<L<0.5Lc1=0.5
There may be a relationship of Lc2. In this way, the display can be made pseudo-impulse type, so that afterimages in the eyes can be suppressed. Alternatively, images with varying luminance may be displayed alternately. In this way, the period in which the luminance changes can be shortened, so that flicker can be reduced.

In this way, there are two different causes of video blur: image motion is not smooth,
By simultaneously solving the problems of blurring (image lag and eye retention), motion blur can be significantly reduced.

Furthermore, the (p+4)th image 180715 and the (p+5)th image 180716 may also be created from the (p+3)th image 180714 and the (p+6)th image 180717 using a similar method. That is, the (p+4)th image 180715 and the (p+5)th image 180716 are generated by detecting the amount of change in the (p+3)th image 180714 to the (p+6)th image 180717.
It may be an image created so as to be in an intermediate state between the fourth and (p+6)th images 180717, and further, an image in which the brightness of the image is controlled according to a certain rule.

Furthermore, when the method of Figure 71 (B) is used, the display frame rate is high, so that the movement of the image can closely track the movement of the eyes and the movement of the image can be displayed smoothly, thereby significantly reducing video blur.

FIG. 71C shows a case where the display frame rate is 1.5 times the input frame rate (conversion ratio 1.5
FIG. 71C shows a schematic diagram of the change in the displayed image over time, with the horizontal axis representing time. Image 180721 is the pth image, image 1
Image 80722 is the (p+1)th image, image 180723 is the (p+2)th image, and image 180
It is assumed that image 180725 is input image data, and image 180722 is the (p+1)th image, and image 180724 is the (p+3)th image, although they do not need to be actually displayed.
71C shows a case where the conversion ratio is 1.5, the period Tin is 1.5 times as long as the period from when the pth image is displayed to when the (p+1)th image is displayed.

Here, the (p+1)th image 180722 and the (p+2)th image 180723 are obtained by dividing the pth image 180721 through the pth image 180725 and then dividing the pth image 180724 into the (p+3)th image 180724.
By detecting the amount of change in the image up to the (p+3)th image, an image may be created so as to be in an intermediate state between the pth image 180721 and the (p+3)th image 180724. In Fig. 71(C), the intermediate state image is represented by an area (circular area) whose position changes depending on the frame, and an area (triangular area) whose position hardly changes depending on the frame.
That is, the positions of the circular regions in the (p+1)th image 180722 and the (p+2)th image 180723 are intermediate between the positions in the pth image 180721 and the (p+3)th image 180724.
The (p+2)th image 180722 and the (p+2)th image 180723 are obtained by performing motion compensation and interpolating the image data. In this way, by performing motion compensation on a moving object on an image and interpolating the image data, a smooth display can be achieved.

Furthermore, the (p+1)th image 180722 and the (p+2)th image 180723 may be images created to be intermediate between the pth image 180721 and the (p+3)th image 180724, and the brightness of the images may be controlled according to a certain rule. The certain rule may be, for example, as shown in FIG. 71C, where the representative brightness of the pth image 180721 is L, the representative brightness of the (p+3)th image 180724 is L, and the representative brightness of the (p+4)th image 180724 is L.
The representative luminance of the (p+1)th image 180722 is Lc1, and the representative luminance of the (p+2)th image 180723 is Lc2.
When the representative luminance is Lc2, L, Lc1, and Lc2, L>Lc1 or L
>Lc2 or Lc1=Lc2. Preferably, 0.1L<Lc
The relationship may be 1=Lc2<0.8L. More preferably, the relationship is 0.2L<Lc=
There may be a relationship of Lc2<0.5L. Alternatively, conversely, there may be a relationship of L<Lc1, L<Lc2, or Lc1=Lc2 among L, Lc1, and Lc2. Desirably, there may be a relationship of 0.1Lc1=0.1Lc2<L<0.8Lc1=0.8Lc2. More desirably, there may be a relationship of 0.2Lc1=0.2Lc2<L<0.5Lc1=0.5
There may be a relationship of Lc2. In this way, the display can be made pseudo-impulse type, so that afterimages in the eyes can be suppressed. Alternatively, images with varying luminance may be displayed alternately. In this way, the period in which the luminance changes can be shortened, so that flicker can be reduced.

In this way, there are two different causes of video blur: image motion is not smooth,
By simultaneously solving the problems of blurring (image lag and eye retention), motion blur can be significantly reduced.

In addition, when the method of Fig. 71(C) is used, the display frame rate is small, so the time to write signals to the display device can be made longer. Therefore, the clock frequency of the display device can be made smaller, so power consumption can be reduced. In addition, the processing speed for motion compensation can be slowed down, so power consumption can be reduced.

Next, a typical brightness of an image will be described with reference to FIG.
The diagram shown in Fig. 72(E) shows an example of a method for measuring the luminance of an image in a certain area.

One method for measuring the luminance of an image is to measure the luminance of each pixel that composes the image individually. By using this method, the luminance of even the finest details of the image can be measured precisely.

However, since the method of measuring the luminance of each pixel constituting an image individually requires a great deal of work, another method may be used. Another method of measuring the luminance of an image is to focus on a certain area in the image and measure the average luminance of that area. This method makes it possible to measure the luminance of an image easily. In this embodiment, for the sake of convenience, the luminance obtained by the method of measuring the average luminance of a certain area in an image is referred to as the representative luminance of the image.

The following describes which area in an image should be focused on in order to obtain the representative brightness of the image.

72A shows an example of a method for determining the luminance of an area (triangular area) whose position does not change substantially with respect to changes in the image as the representative luminance of the image. The period Tin is the cycle of the input image data, image 180801 is the pth image, image 180802 is the (p+1)th image, image 180803 is the (p+1)th image, and image 180804 is the (p+1)th image.
0803 represents the (p+2)th image, the first region 180804 represents the luminance measurement region in the pth image 180801, the second region 180805 represents the luminance measurement region in the (p+1)th image 180802, and the third region 180806 represents the luminance measurement region in the (p+2)th image 180803. Here, the first to third regions may be assumed to be approximately the same in terms of spatial position within the device. In other words, by measuring the representative luminance of the image in the first to third regions, it is possible to obtain the time change of the representative luminance of the image.

By measuring the representative luminance of the image, it is possible to determine whether the display is pseudo-impulsive. For example, let the luminance measured in the first region 180804 be L,
When the luminance measured in the second region 180805 is Lc, if Lc<L, the display can be said to be pseudo-impulse type. In such a case, the quality of the moving image can be said to be improved.

In addition, in the brightness measurement area, when the amount of change in the representative brightness of the image with respect to the change in time (relative brightness) is in the following range, the image quality can be improved. For example, the relative brightness can be the ratio of the smaller brightness to the larger brightness for each of the first area 180804 and the second area 180805, the second area 180805 and the third area 180806, and the first area 180804 and the third area 180806. In other words, when the amount of change in the representative brightness of the image with respect to the change in time is 0, the relative brightness is 100%. And, if the relative brightness is 80% or less, the quality of the moving image can be improved. In particular, if the relative brightness is 50% or less, the quality of the moving image can be significantly improved. Furthermore, if the relative brightness is 10% or more, the power consumption can be reduced and flicker can be suppressed. In particular, if the relative brightness is 2
If the ratio is 0% or more, power consumption and flicker can be significantly reduced.
If the relative luminance is between 10% and 80%, the quality of the moving image can be improved and the power consumption and flicker can be reduced. Furthermore, if the relative luminance is between 20% and 50%, the quality of the moving image can be significantly improved and the power consumption and flicker can be significantly reduced.

72B shows an example of a method for measuring the brightness of an area divided into tiles and taking the average value as the representative brightness of the image. The period Tin is the cycle of the input image data, and the image 1808
Image 180811 is the pth image, image 180812 is the (p+1)th image, and image 180813 is the (p
The first region 180814 represents a luminance measurement region in the pth image 180811, the second region 180815 represents a luminance measurement region in the (p+1)th image 180812, and the third region 180816 represents a luminance measurement region in the (p+2)th image 180813. Here, the first to third regions may be assumed to be approximately the same in terms of spatial position within the device. In other words, by measuring the representative luminance of the image in the first to third regions, it is possible to obtain a time change in the representative luminance of the image.

By measuring the representative luminance of the image, it is possible to determine whether the display is pseudo-impulse type. For example, when the average value of the luminance measured in the first region 180814 is L and the average value of the luminance measured in the second region 180815 is Lc, if Lc<L, the display is said to be pseudo-impulse type. In such a case, the quality of the moving image is said to be improved.

In addition, in the brightness measurement area, when the amount of change in the representative brightness of the image with respect to the change in time (relative brightness) is in the following range, the image quality can be improved. For example, the relative brightness can be the ratio of the smaller brightness to the larger brightness for each of the first area 180814 and the second area 180815, the second area 180815 and the third area 180816, and the first area 180814 and the third area 180816. In other words, when the amount of change in the representative brightness of the image with respect to the change in time is 0, the relative brightness is 100%. And, if the relative brightness is 80% or less, the quality of the moving image can be improved. In particular, if the relative brightness is 50% or less, the quality of the moving image can be significantly improved. Furthermore, if the relative brightness is 10% or more, the power consumption can be reduced and flicker can be suppressed. In particular, if the relative brightness is 2
If the ratio is 0% or more, power consumption and flicker can be significantly reduced.
If the relative luminance is between 10% and 80%, the quality of the moving image can be improved and the power consumption and flicker can be reduced. Furthermore, if the relative luminance is between 20% and 50%, the quality of the moving image can be significantly improved and the power consumption and flicker can be significantly reduced.

Fig. 72(C) shows an example of a method for measuring the luminance of the central region of an image and taking the average value as the representative luminance of the image. The period Tin represents the cycle of the input image data, the image 180821 represents the pth image, the image 180822 represents the (p+1)th image, the image 180823 represents the (p+2)th image, the first region 180824 represents the luminance measurement region in the pth image 180821, the second region 180825 represents the luminance measurement region in the (p+1)th image 180822, and the third region 180826 represents the luminance measurement region in the (p+2)th image 180823.

By measuring the representative luminance of the image, it is possible to determine whether the display is pseudo-impulsive. For example, let the luminance measured in the first region 180824 be L,
When the luminance measured in the second region 180825 is Lc, if Lc<L, the display can be said to be pseudo-impulse type. In such a case, the quality of the moving image can be said to be improved.

In addition, in the brightness measurement area, when the change amount of the representative brightness of the image with respect to the change in time (relative brightness) is in the following range, the image quality can be improved. For example, the relative brightness can be the ratio of the smaller brightness to the larger brightness for each of the first area 180824 and the second area 180825, the second area 180825 and the third area 180826, and the first area 180824 and the third area 180826. In other words, when the change amount of the representative brightness of the image with respect to the change in time is 0, the relative brightness is 100%. And, if the relative brightness is 80% or less, the quality of the moving image can be improved. In particular, if the relative brightness is 50% or less, the quality of the moving image can be significantly improved. Furthermore, if the relative brightness is 10% or more, the power consumption can be reduced and flicker can be suppressed. In particular, if the relative brightness is 2
If the ratio is 0% or more, power consumption and flicker can be significantly reduced.
If the relative luminance is between 10% and 80%, the quality of the moving image can be improved and the power consumption and flicker can be reduced. Furthermore, if the relative luminance is between 20% and 50%, the quality of the moving image can be significantly improved and the power consumption and flicker can be significantly reduced.

Fig. 72(D) shows an example of a method in which the luminance of a plurality of sampled points from the entire image is measured and the average value is taken as the representative luminance of the image. The period Tin is the period of the input image data,
Image 180831 is the pth image, image 180832 is the (p+1)th image, and image 1808
33 represents the (p+2)th image, the first region 180834 represents the brightness measurement region in the pth image 180831, the second region 180835 represents the brightness measurement region in the (p+1)th image 180832, and the third region 180836 represents the brightness measurement region in the (p+2)th image 180833.

By measuring the representative luminance of the image, it is possible to determine whether the display is pseudo-impulse type. For example, when the average value of the luminance measured in the first region 180834 is L and the average value of the luminance measured in the second region 180835 is Lc, if Lc<L, the display is said to be pseudo-impulse type. In such a case, the quality of the moving image is said to be improved.

In addition, in the brightness measurement area, when the change amount of the representative brightness of the image with respect to the change in time (relative brightness) is in the following range, the image quality can be improved. For example, the relative brightness can be the ratio of the smaller brightness to the larger brightness for each of the first area 180834 and the second area 180835, the second area 180835 and the third area 180836, and the first area 180834 and the third area 180836. In other words, when the change amount of the representative brightness of the image with respect to the change in time is 0, the relative brightness is 100%. And, if the relative brightness is 80% or less, the quality of the moving image can be improved. In particular, if the relative brightness is 50% or less, the quality of the moving image can be significantly improved. Furthermore, if the relative brightness is 10% or more, the power consumption can be reduced and flicker can be suppressed. In particular, if the relative brightness is 2
If the ratio is 0% or more, power consumption and flicker can be significantly reduced.
If the relative luminance is between 10% and 80%, the quality of the moving image can be improved and the power consumption and flicker can be reduced. Furthermore, if the relative luminance is between 20% and 50%, the quality of the moving image can be significantly improved and the power consumption and flicker can be significantly reduced.

Fig. 72(E) is a diagram showing a method of measuring within the luminance measurement area in the diagrams shown in Fig. 72(A) to (D). Area 180841 is the luminance measurement area of interest, and point 180842 is a luminance measurement point within area 180841. Since a luminance measuring device with high time resolution may have a small measurement range, when area 180841 is large, instead of measuring the entire area, it is also possible to measure multiple points within area 180841 without bias in a point-like manner as shown in Fig. 72(E), and take the average value as the luminance of area 180841.

If the image has a combination of the three primary colors R, G, and B, the measured luminance is
The luminance may be the combined luminance of R and G, the combined luminance of G and B, the combined luminance of B and R, or the luminance of each of R, G, and B.

Next, a method for detecting image motion in the input image data and creating an intermediate state image;
Also, a method of controlling the driving method in accordance with the motion of an image contained in input image data will be described.

An example of a method for detecting the motion of an image contained in input image data and creating an intermediate state image will be described with reference to Fig. 73. Fig. 73(A) shows a case where the display frame rate is twice the input frame rate (conversion ratio is 2). Fig. 73(A) shows a schematic diagram of a method for detecting the motion of an image with the horizontal axis being time. The period Tin is the cycle of the input image data, image 180901 is the pth image, image 180902 is the (p+1)th image, and so on.
In the images, a first region 180904, a second region 180905, and a third region 180906 are provided as regions that do not depend on time.

First, in the (p+2)th image 180903, the image is divided into a number of tile-shaped regions, and attention is focused on the image data within one of these regions, the third region 180906.

Next, in the p-th image 180901, a range larger than the third region 180906 and centered on the third region 180906 is considered. Here, the range larger than the third region 180906 and centered on the third region 180906 is a data search range. The data search range is a horizontal range (X direction) 180907 and a vertical range (Y direction) 180908.
08. Note that horizontal range 180907 and vertical range 180908 of the data search range may be ranges obtained by expanding the horizontal range and vertical range of third area 180906 by about 15 pixels, respectively.

Then, within the data search range, a search is performed for a region having image data most similar to the image data in the third region 180906. The search method may be the least squares method or the like. As a result of the search, the first region 18090 is found to have the most similar image data.
Suppose 4 is derived.

Next, a vector 180909 is derived as an amount representing the difference in position between the derived first region 180904 and the third region 180906. Note that vector 180909 is referred to as a motion vector.

Then, in the (p+1)th image 180902, a second region 180905 is formed using the vector obtained from the motion vector 180909, the image data in the third region 180906 in the (p+2)th image 180903, and the image data in the first region 180904 in the pth image 180901.

Here, the vector calculated from the motion vector 180909 is referred to as a displacement vector 180910. The displacement vector 180910 plays a role in determining the position at which the second region 180905 is formed. The second region 180905 is formed at a position that is the displacement vector 180910 away from the third region 180906. Note that the displacement vector 180910 may be an amount obtained by multiplying the motion vector 180909 by a coefficient (1/2).

The image data in the second region 180905 in the (p+1)th image 180902 is compared with the image data in the third region 180906 in the (p+2)th image 180903.
For example, the (p+1)th image 180902 may be determined by image data in a first region 180904 in the (p+1)th image 180901.
The image data in 180905 corresponds to the third region 18090 in the (p+2)th image 180903.
6 and the average value of the image data in the first region 180904 in the pth image 180901.

In this manner, it is possible to form the second region 180905 in the (p+1)th image 180902, which corresponds to the third region 180906 in the (p+2)th image 180903. Note that by performing the above processing on other regions in the (p+2)th image 180903, it is possible to form the (p+1)th image 180902, which is an intermediate state between the (p+2)th image 180903 and the pth image 180901.

Fig. 73B shows a case where the display frame rate is three times the input frame rate (the conversion ratio is 3). Fig. 73B shows a schematic diagram of a method for detecting image motion with the horizontal axis representing time. The period Tin is the period of the input image data, and the image 1809
Image 180911 is the pth image, image 180912 is the (p+1)th image, and image 180913 is the (p
Image 180914 represents the (p+3)th image, and image 180915 represents the (p+4)th image.
In the image, a first region 180915 and a second region 1809 are defined as regions that are not dependent on time.
16, a third region 180917 and a fourth region 180918 are provided.

First, in the (p+3)th image 180914, the image is divided into multiple tile-shaped regions, and attention is focused on the image data within one of these regions, the fourth region 180918.

Next, in the pth image 180911, a range larger than the fourth region 180918 and centered on the fourth region 180918 is considered. Here, the range larger than the fourth region 180918 and centered on the fourth region 180918 is the data search range. The data search range is a horizontal range (X direction) of 180919 and a vertical range (Y direction) of 180919.
The horizontal range 180919 and the vertical range 180920 of the data search range may be ranges obtained by expanding the horizontal range and the vertical range of the fourth area 180918 by about 15 pixels, respectively.

Then, within the data search range, a search is performed for a region having image data most similar to the image data in the fourth region 180918. The search method may be the least squares method or the like. As a result of the search, the first region 18091 is found to have the most similar image data.
Suppose 5 is derived.

Next, a vector is derived as an amount representing the difference in position between the derived first region 180915 and the fourth region 180918. This vector is called a motion vector 180921.
Let's call it this.

In the (p+1)th image 180912 and the (p+2)th image 180913, the first vector and the second vector obtained from the motion vector 180921 are
The image data in the fourth region 180918 in the (p+3)th image 180914 and the image data in the first region 180915 in the pth image 180911 form a second region 180916 and a third region 180917.

Here, the first vector obtained from the motion vector 180921 is the first displacement vector 18
0922. The second vector will be referred to as a second displacement vector 180923. The first displacement vector 180922 has a role of determining a position for forming the second region 180916. The second region 180916 is formed at a position away from the fourth region 180918 by the first displacement vector 180922. Note that the first displacement vector 180922 may be an amount obtained by multiplying the motion vector 180921 by (1/3). The second displacement vector 180923 has a role of determining a position for forming the third region 180917. The third region 180917 is formed at a position away from the fourth region 180918 by the second displacement vector 180923. Note that the second displacement vector 180923
may be the motion vector 180921 multiplied by (2/3).

The image data in the second region 180916 in the (p+1)th image 180912 is compared with the image data in the fourth region 180918 in the (p+3)th image 180914 and the image data in the pth region 180916 in the (p+2)th image 180916.
For example, the (p+1)th image 180912 may be determined by image data in a first region 180915 in the (p+1)th image 180911.
The image data in 16 is the fourth region 18091 in the (p+3)th image 180914.
8 and the average value of the image data in the first region 180915 in the pth image 180911.

The image data in the third region 180917 in the (p+2)th image 180913 is image data in the fourth region 180918 in the (p+3)th image 180914 and the image data in the pth region 180916 in the (p+4)th image 180917.
For example, the image data in the third region 1809 in the (p+2)th image 180913 may be determined by the image data in the first region 1809 in the (p+2)th image 180911.
The image data in 17 is the fourth region 18091 in the (p+3)th image 180914.
8 and the average value of the image data in the first region 180915 in the pth image 180911.

In this manner, the second region 180916 in the (p+1)th image 180902, which corresponds to the fourth region 180918 in the (p+3)th image 180914, and the
A third region 180917 in image 180913 of pixel p+2 may be formed.
In addition, by performing the above processing on other regions in the (p+3)th image 180914, a (p+3)th image 180915 having an intermediate state between the (p+3)th image 180914 and the pth image 180911 can be obtained.
A (p+1)th image 180912 and a (p+2)th image 180913 can be formed.

Next, referring to Fig. 74, an example of a circuit for detecting the motion of an image contained in input image data and creating an intermediate state image will be described. Fig. 74(A) is a diagram showing the connection relationship between a peripheral driving circuit including a source driver and a gate driver for displaying an image in a display area, and a control circuit for controlling the peripheral driving circuit. Fig. 74(B) is a diagram showing an example of a detailed circuit configuration of the control circuit. Fig. 74(C) is a diagram showing an example of a detailed circuit configuration of an image processing circuit included in the control circuit. Fig. 74(D) is a diagram showing another example of a detailed circuit configuration of an image processing circuit included in the control circuit.

As shown in FIG. 74A, the device in this embodiment mode may include a control circuit 181011, a source driver 181012, a gate driver 181013, and a display region 181014.

The control circuit 181011, the source driver 181012 and the gate driver 181
013 may be formed on the same substrate as the substrate on which the display region 181014 is formed.

The control circuit 181011, the source driver 181012 and the gate driver 181
181013, a part of which may be formed on the same substrate as the substrate on which the display region 181014 is formed, and the other circuits may be formed on a substrate different from the substrate on which the display region 181014 is formed. For example, the source driver 181012 and the gate driver 181013 may be formed on the same substrate as the substrate on which the display region 181014 is formed, and the control circuit 181011 may be formed as an external IC on a different substrate. Similarly, the gate driver 181013 may be formed on the same substrate as the substrate on which the display region 181014 is formed, and the other circuits may be formed as external ICs on a different substrate. Similarly, a part of the source driver 181012, the gate driver 181013, and the control circuit 181011 may be formed on the same substrate as the substrate on which the display region 181014 is formed, and the other circuits may be formed as external ICs on a different substrate.

The control circuit 181011 receives an external image signal 181000, a horizontal sync signal 181001,
A vertical synchronization signal 181002 is input, and an image signal 181003, a source start pulse 181004, a source clock 181005, and a gate start pulse 18100 are input.
6 and gate clock 181007 may be output.

The source driver 181012 receives an image signal 181003 and a source start pulse 181
004 and a source clock 181005 are input, and a voltage or current according to the image signal 181003 is output to a display area 181014.

The gate driver 181013 may be configured to receive a gate start pulse 181006 and a gate clock 181007 and to output a signal that specifies the timing for writing the signal output from the source driver 181012 to the display area 181014.

When the frequency of the external image signal 181000 and the frequency of the image signal 181003 are different, the signals for controlling the timing of driving the source driver 181012 and the gate driver 181013 are also different from the input horizontal sync signal 181001 and vertical sync signal 181002.
18.02. Therefore, in addition to processing the image signal 181003, it is also necessary to process a signal that controls the timing of driving the source driver 181012 and the gate driver 181013. The control circuit 181011 may be a circuit having a function for this purpose. For example, if the frequency of the image signal 181003 is twice that of the external image signal 181000, the control circuit 181011 will process the signal that controls the timing of driving the source driver 181012 and the gate driver 181013.
The image signal included in 1000 is interpolated to generate an image signal 181003 having double the frequency, and the signal controlling the timing is also controlled to have double the frequency.

As shown in FIG. 74B, the control circuit 181011 includes an image processing circuit 181015 and
A timing generating circuit 181016 may also be included.

The image processing circuit 181015 receives an external image signal 181000 and a frequency control signal 18100
8 and an image signal 181003 may be input and output.

The timing generating circuit 181016 generates a horizontal synchronizing signal 181001 and a vertical synchronizing signal 181002.
002 and are input, and a source start pulse 181004 and a source clock 1810
05, a gate start pulse 181006, a gate clock 181007, and a frequency control signal 181008. The timing generating circuit 181016 may include a memory or a register that holds data for specifying the state of the frequency control signal 181008. The timing generating circuit 181016 may be configured to receive a signal that specifies the state of the frequency control signal 181008 from the outside.

The image processing circuit 181015 may include a motion detection circuit 181020, a first memory 181021, a second memory 181022, a third memory 181023, a brightness control circuit 181024, and a high-speed processing circuit 181025, as shown in FIG. 74 (C).

The motion detection circuit 181020 may be configured to receive a plurality of image data, detect the motion of the images, and output image data that is an intermediate state of the plurality of image data.

The first memory 181021 receives an external image signal 181000, and stores the external image signal 181000 for a certain period of time.
The external image signal 181000 may be output to the external image input/output terminal 22.

The second memory 181022 may be configured to receive image data output from the first memory 181021, hold the image data for a certain period of time, and output the image data to the motion detection circuit 181020 and the high-speed processing circuit 181025.

The third memory 181023 may be configured to receive the image data output from the motion detection circuit 181020, hold the image data for a certain period of time, and output the image data to a brightness control circuit 181024.

The high-speed processing circuit 181025 receives the image data output from the second memory 181022,
The image data output from the brightness control circuit 181024 and the frequency control signal 181008 may be input, and the image data may be output as the image signal 181003.

When the frequency of the external image signal 181000 and the frequency of the image signal 181003 are different, the image processing circuit 181015 may generate the image signal 181003 by interpolating the image signal included in the external image signal 181000.
0 is temporarily stored in the first memory 181021. At that time, the second memory 18102
The image data input in the previous frame is held in the motion detection circuit 18.
1020 reads image data stored in a first memory 181021 and a second memory 181022 as appropriate, detects a motion vector from the difference between the two image data, and further
The image data in the intermediate state may be generated. The generated image data in the intermediate state is stored in the third memory 181023.

When the motion detection circuit 181020 is generating image data of an intermediate state, the high-speed processing circuit 1
81025 converts the image data held in the second memory 181022 into an image signal 18
The image data held in the third memory 181023 is then output as an image signal 181003 through a luminance control circuit 181024. At this time, the frequency at which the second memory 181022 and the third memory 181023 are updated is the same as the frequency of the external image signal 181000, but the frequency of the image signal 181003 output through the high-speed processing circuit 181025 may be different from the frequency of the external image signal 181000. Specifically, for example, the frequency of the image signal 181003 is
Examples of the frequency of the image signal 181003 include 1.5 times, 2 times, and 3 times the frequency of the image signal 181003. However, the frequency is not limited to this, and various frequencies can be used. The frequency of the image signal 181003 may be specified by a frequency control signal 181008.

The configuration of the image processing circuit 181015 shown in Fig. 74(D) is obtained by adding a fourth memory 181026 to the configuration of the image processing circuit 181015 shown in Fig. 74(C).
By outputting image data output from the fourth memory 181026 in addition to the image data output from the third memory 181028 to the motion detection circuit 181020, it becomes possible to accurately detect the motion of the image.

In addition, when the input image data already contains a motion vector due to data compression or the like, for example, MPEG (Moving Picture Expert Group)
In the case where the image data is based on the standard of the 3D image processing circuit 181003, an intermediate image can be generated as an interpolated image using the image data. In this case, the part that generates the motion vector included in the motion detection circuit 181020 becomes unnecessary. In addition, the encoding and decoding processes related to the image signal 181003 become simple, so that power consumption can be reduced.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 6)
In this embodiment, the peripheral portion of the liquid crystal panel will be described.

FIG. 75 shows a backlight unit 20101 called an edge light type and a liquid crystal panel 20102.
1 shows an example of a liquid crystal display device having the above-mentioned structure. The edge light type is a type in which a light source is disposed at an end of a backlight unit, and the fluorescent light of the light source is emitted from the entire light emitting surface.
Edge-light type backlight units are thin and can reduce power consumption.

The backlight unit 20101 includes a diffusion plate 20102, a light guide plate 20103, and a reflector plate 20
104, a lamp reflector 20105 and a light source 20106.

The light source 20106 has a function of emitting light as required. For example, a cold cathode fluorescent lamp, a hot cathode fluorescent lamp, a light emitting diode, an inorganic EL, or an organic EL may be used as the light source 20106. The lamp reflector 20105 has a function of efficiently guiding the fluorescent light from the light source 20106 to the light guide plate 20103. The light guide plate 20103 has a function of totally reflecting the fluorescent light and guiding the light to the entire surface. The diffusion plate 20102 has a function of reducing unevenness in brightness. The reflector 20104 has a function of:
It has the function of reflecting and reusing light that leaks downward from the light guide plate 20103 (in the direction opposite to the liquid crystal panel 20107).

A control circuit for adjusting the luminance of the light source 20106 is connected to the backlight unit 20101. The luminance of the light source 20106 can be adjusted by this control circuit.

76(A), (B), (C) and (D) are diagrams showing the detailed configuration of an edge-light type backlight unit, in which explanations of the diffusion plate, light guide plate and reflector plate are omitted.

The backlight unit 20201 shown in FIG. 76(A) uses a cold cathode fluorescent lamp 20203 as a light source.
In order to efficiently reflect the light from the cold cathode fluorescent lamp 20203,
There is provided a lamp reflector 20202. This configuration is often used in large display devices due to the intensity of the luminance from the cold cathode fluorescent lamps.

The backlight unit 20211 shown in FIG. 76(B) uses a light emitting diode (LED) as a light source.
For example, a white light emitting diode (LED) 20213 is used.
The light emitting diodes (LEDs) 20213 are arranged at predetermined intervals. In order to efficiently reflect light from the light emitting diodes (LEDs) 20213, a lamp reflector 20212 is provided.

Since light-emitting diodes have high brightness, configurations using light-emitting diodes are suitable for large display devices. Light-emitting diodes have excellent color reproducibility, so they can display images that are closer to the real thing. LEDs have small chips, so the layout area can be reduced. This makes it possible to narrow the frame of the display device.

In addition, when the light emitting diodes are mounted on a large display device, the light emitting diodes can be arranged on the back surface of the substrate. The light emitting diodes are arranged at a predetermined interval, and the light emitting diodes of each color are arranged in order. The arrangement of the light emitting diodes can improve color reproducibility.

The backlight unit 20221 shown in FIG. 76C is configured to use light emitting diodes (LED) 20223, 20224, and 20225 of the respective colors RGB as light sources.
The light emitting diodes (LED) 20223, the light emitting diodes (LED) 20224, and the light emitting diodes (LED) 20225 are arranged at predetermined intervals.
Color reproducibility can be improved by using a light emitting diode (LED) 20224 and a light emitting diode (LED) 20225. A lamp reflector 20222 is provided to efficiently reflect light from the light emitting diodes.

Since light-emitting diodes have high brightness, configurations using light-emitting diodes of each color (RGB) as a light source are suitable for large display devices. Light-emitting diodes have excellent color reproducibility, so they can display images that are closer to the real thing. LEDs have small chips, so they can be placed in a small area.
Therefore, the frame of the display device can be narrowed.

It should be noted that a color display can be achieved by sequentially lighting the RGB light emitting diodes according to time, in what is called a field sequential mode.

In addition, a light emitting diode that emits white light and a light emitting diode (LED) 2022 for each color RGB are
3. Light emitting diode (LED) 20224 and light emitting diode (LED) 20225 can be combined.

In addition, when the light emitting diodes are mounted on a large display device, the light emitting diodes can be arranged on the back surface of the substrate. The light emitting diodes are arranged at a predetermined interval, and the light emitting diodes of each color are arranged in order. The arrangement of the light emitting diodes can improve color reproducibility.

The backlight unit 20231 shown in Fig. 77(D) is configured to use light emitting diodes (LED) 20233, 20234, and 20235 of the respective colors RGB as light sources.
D) 20233, light emitting diode (LED) 20234, light emitting diode (LED) 20
Among the LEDs 20235, a plurality of LEDs 20233, 20234, and 20235 having low light emission intensity are arranged. Color reproducibility can be improved by using light emitting diodes (LED) 20233, 20234, and 20235 for each of the RGB colors. A lamp reflector 20232 is provided to efficiently reflect light from the light emitting diodes.

Since light-emitting diodes have high brightness, configurations using light-emitting diodes of each color (RGB) as a light source are suitable for large display devices. Light-emitting diodes have excellent color reproducibility, so they can display images that are closer to the real thing. LEDs have small chips, so they can be placed in a small area.
Therefore, the frame of the display device can be narrowed.

It should be noted that a color display can be achieved by sequentially lighting the RGB light emitting diodes according to time, in what is called a field sequential mode.

In addition, a light emitting diode that emits white light and a light emitting diode (LED) 2023 for each color RGB are
3. Light emitting diode (LED) 20234 and light emitting diode (LED) 20235 can be combined.

In addition, when the light emitting diodes are mounted on a large display device, the light emitting diodes can be arranged on the back surface of the substrate. The light emitting diodes are arranged at a predetermined interval, and the light emitting diodes of each color are arranged in order. The arrangement of the light emitting diodes can improve color reproducibility.

Fig. 79(A) shows an example of a liquid crystal display device having a backlight unit called a direct type and a liquid crystal panel. The direct type is a method in which a light source is placed directly under the light-emitting surface, and the fluorescence of the light source is emitted from the entire light-emitting surface. The direct type backlight unit can efficiently use the amount of emitted light.

The backlight unit 20500 is composed of a diffusion plate 20501 , a light blocking plate 20502 , a lamp reflector 20503 , and a light source 20504 .

Light emitted from the light source 20504 is collected on one side of the backlight unit 20500 by the lamp reflector 20503.
In this case, by disposing the liquid crystal panel 20505 on the side of the backlight unit 20500 that emits strong light, the light emitted from the light source 20504 can be efficiently irradiated onto the liquid crystal panel 20505.

The light source 20504 has a function of emitting light as necessary. For example, a cold cathode fluorescent lamp, a hot cathode fluorescent lamp, a light emitting diode, an inorganic EL, or an organic EL is used as the light source 20504. The lamp reflector 20503 has a function of efficiently guiding the fluorescence of the light source 20504 to the diffusion plate 20501 and the light shielding plate 20502. The light shielding plate 20502 has a function of reducing unevenness in brightness by increasing the amount of light shielding in areas where the light is stronger in accordance with the arrangement of the light source 20504. The diffusion plate 20501 has a function of further reducing unevenness in brightness.

A control circuit for adjusting the luminance of the light source 20504 is connected to the backlight unit 20500. The luminance of the light source 20504 can be adjusted by this control circuit.

Fig. 79(B) shows an example of a liquid crystal display device having a backlight unit called a direct type and a liquid crystal panel. The direct type is a method in which a light source is placed directly under the light-emitting surface, and the fluorescence of the light source is emitted from the entire light-emitting surface. The direct type backlight unit can efficiently use the amount of emitted light.

The backlight unit 20510 is composed of a diffusion plate 20511, a light shielding plate 20512, a lamp reflector 20513, and a light source (R) 20514a, a light source (G) 20514b, and a light source (B) 20514c for each of the colors RGB.

The light emitted from the light source (R) 20514a, the light source (G) 20514b, and the light source (B) 20514c is collected on one surface of the backlight unit 20510 by the lamp reflector 20513. In other words, the backlight unit 20510 has a surface that emits strong light and a surface that hardly emits light.
By disposing the liquid crystal panel 20515 on the side of the light source (R) 205 that emits strong light,
The light emitted from the light source (G) 20514a, the light source (G) 20514b, and the light source (B) 20514c can be efficiently irradiated onto the liquid crystal panel 20515.

The light source (R) 20514a, the light source (G) 20514b and the light source (B) 2051
4c has a function of emitting light as necessary. For example, the light source (R) 20514a, the light source (
As the light source (G) 20514b and the light source (B) 20514c, a cold cathode tube, a hot cathode tube, a light emitting diode, an inorganic EL, an organic EL, or the like is used. The lamp reflector 20513 has a function of efficiently guiding the fluorescence of the light source 20514 to the diffusion plate 20511 and the light shielding plate 20512. The light shielding plate 20512 has a function of reducing unevenness in brightness by blocking more light in areas where the light is stronger in accordance with the arrangement of the light source 20514. The diffusion plate 20511 has a function of further reducing unevenness in brightness.

A control circuit for adjusting the luminance of the light source (R) 20514a, the light source (G) 20514b, and the light source (B) 20514c of each color RGB is connected to the backlight unit 20510.
The brightness of light source (A) 20514b and light source (B) 20514c can be adjusted.

Figure 77 shows an example of the configuration of a polarizing plate (also called a polarizing film).

The polarizing film 20300 includes a protective film 20301, a substrate film 20302, and a PVA
It has a polarizing film 20303 , a substrate film 20304 , an adhesive layer 20305 and a release film 20306 .

The PVA polarizing film 20303 has a function of producing light that vibrates in only one direction (linearly polarized light). Specifically, the PVA polarizing film 20303 contains molecules (polarizers) whose electron densities differ greatly between the vertical and horizontal directions. The PVA polarizing film 20303 can produce linearly polarized light by aligning the directions of the molecules whose electron densities differ greatly between the vertical and horizontal directions.

As an example, PVA polarizing film 20303 is made of polyvinyl alcohol (Poly V
By doping a polymer film of polyvinyl alcohol (PVA) with an iodine compound and pulling the PVA film in a certain direction, a film in which iodine molecules are aligned in a certain direction can be obtained. Light parallel to the long axis of the iodine molecules is absorbed by the iodine molecules. For high durability and high heat resistance applications, a dichroic dye may be used instead of iodine. The dye is preferably used in liquid crystal display devices that require durability and heat resistance, such as LCDs for vehicles or LCDs for projectors.

The PVA polarizing film 20303 is a film having a substrate on both sides (substrate film 20302
The reliability can be increased by sandwiching the PVA substrate between the PVA and the substrate film 20304.
The polarizing film 20303 may be sandwiched between highly transparent and highly durable triacetylcellulose (TAC) films. The substrate film and the TAC films function as protective layers for the polarizer of the PVA polarizing film 20303.

An adhesive layer 20305 is attached to one of the substrate films (substrate film 20304) for attaching to a glass substrate of a liquid crystal panel. The adhesive layer 20305 is formed by applying an adhesive to the substrate film (substrate film 20304) on one side.
05 is provided with a release film 20306 (separate film).

The other substrate film (substrate film 20302 ) is provided with a protective film 20301 .

In addition, a hard coat scattering layer (anti-glare layer) may be provided on the surface of the polarizing film 20300. The hard coat scattering layer has fine irregularities formed on the surface by AG treatment and has an anti-glare function that scatters external light, so that it is possible to prevent external light from being reflected on the liquid crystal panel. Surface reflection can be prevented.

In addition, a plurality of optical thin film layers having different refractive indexes may be multi-layered (also called anti-reflection treatment or AR treatment) on the surface of the polarizing film 20300. The multi-layered optical thin film layers having different refractive indexes can reduce the reflectance of the surface by the optical interference effect.

Figure 78 shows an example of a system block of a liquid crystal display device.

In the pixel portion 20405, a signal line 20412 is arranged extending from a signal line driver circuit 20403. In the pixel portion 20405, a scanning line 20410 is arranged extending from a scanning line driver circuit 20404. A plurality of pixels are arranged in a matrix shape in an intersection region between the signal line 20412 and the scanning line 20410. Each of the plurality of pixels has a switching element. Therefore, a voltage for controlling the tilt of the liquid crystal molecules can be input independently to each of the plurality of pixels. A structure in which a switching element is provided in each intersection region in this way is called an active type. However, it is not limited to such an active type, and a passive type configuration may be used. In the passive type, since each pixel does not have a switching element, the process is simple.

The driver circuit portion 20408 includes a control circuit 20402, a signal line driver circuit 20403, and a scanning line driver circuit 20404. A video signal 20401 is input to the control circuit 20402. The control circuit 20402 controls the signal line driver circuit 2040 in response to the video signal 20401.
3 and the scanning line driver circuit 20404. To this end, the video signal 20401 inputs control signals to the signal line driver circuit 20403 and the scanning line driver circuit 20404. In response to these control signals, the signal line driver circuit 20403 outputs a video signal to the signal line 2041.
2, and the scanning line driver circuit 20404 inputs a scanning signal to a scanning line 20410. Then, a switching element of the pixel is selected in response to the scanning signal, and a video signal is input to a pixel electrode of the pixel.

The control circuit 20402 also controls the power supply 20407 in response to the video signal 20401. The power supply 20407 has a means for supplying power to the lighting means 20406. As the lighting means 20406, an edge-light type backlight unit or a direct type backlight unit can be used. However, a front light may also be used as the lighting means 20406. A front light is a plate-shaped light unit that is attached to the front side of the pixel section and is made up of a light emitter and a light guide for illuminating the entire area. With such lighting means,
It consumes low power and can illuminate the pixel area evenly.

78B, the scanning line driver circuit 20404 has circuits functioning as a shift register 20441, a level shifter 20442, and a buffer 20443. To the shift register 20441, signals such as a gate start pulse (GSP) and a gate clock signal (GCK) are input.

As shown in FIG. 78C, the signal line driver circuit 20403 includes a shift register 20431, a first latch 20432, a second latch 20433, a level shifter 20434, a buffer 20435, and a gate 20436.
The circuit functioning as the buffer 20435 is a circuit having a function of amplifying a weak signal, and includes an operational amplifier.
A signal such as a start pulse (SSP) is input to the first latch 20434, and data (DATA) such as a video signal is input to the first latch 20432. A latch (LAT
) signal can be temporarily held and input to the pixel portion 20405 at the same time. This is called line sequential driving. Therefore, if the pixel is driven by dot sequential driving instead of line sequential driving, the second latch is not necessary.

In this embodiment, a known liquid crystal panel can be used. For example, the liquid crystal panel can have a structure in which a liquid crystal layer is sealed between two substrates.
On one of the substrates, a transistor, a capacitance element, a pixel electrode, an alignment film, etc. are formed. A polarizing plate, a retardation plate, or a prism sheet may be arranged on the side opposite to the upper surface of the one substrate. A color filter, a black matrix, a counter electrode, an alignment film, etc. are formed on the other substrate. A polarizing plate or a retardation plate may be arranged on the side opposite to the upper surface of the other substrate. The color filter and the black matrix may be formed on the upper surface of one of the substrates. A slit (
By arranging the pixels in a grid, a three-dimensional display can be achieved.

The polarizing plate, the retardation plate, and the prism sheet may each be disposed between the two substrates, or may be integrated with one of the two substrates.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Seventh embodiment)
In this embodiment mode, a structure and an operation of a pixel that can be applied to a liquid crystal display device will be described.

In this embodiment, the liquid crystal is operated in a Twisted Nematic (TN) mode.
atic) mode, IPS (In-Plane-Switching) mode, FFS (
Fringe Field Switching mode, MVA (Multi-dom)
Vertical Alignment mode, PVA (Patterned
Vertical Alignment), ASM (Axial Symmeter)
ic aligned Micro-cell mode, OCB (Optical Co
mpensated Birefringence) mode, FLC (Ferroele
ctric Liquid Crystal) mode, AFLC (AntiFerroe
Electric Liquid Crystal, etc. can be used.

Figure 131(A) shows an example of a pixel configuration that can be applied to a liquid crystal display device.

The pixel 40100 includes a transistor 40101, a liquid crystal element 40102, and a capacitor element 4010.
The gate of the transistor 40101 is connected to a wiring 40105.
A first terminal of the transistor 40101 is connected to a wiring 40104.
A second terminal of the liquid crystal element 40101 is connected to a first electrode of a liquid crystal element 40102 and a first electrode of a capacitor element 40103. A second electrode of the liquid crystal element 40102 corresponds to a counter electrode 40107. A second electrode of the capacitor element 40103 is connected to a wiring 40106.

The wiring 40104 functions as a signal line. The wiring 40105 functions as a scan line. The wiring 40106 functions as a capacitor line. The transistor 40101 functions as a switch. The capacitor 40103 functions as a storage capacitor.

The transistor 40101 is only required to function as a switch, and the polarity of the transistor 40101 may be either a P-channel type or an N-channel type.

A video signal is input to the wiring 40104. A scanning signal is input to the wiring 40105. A certain potential is supplied to the wiring 40106. The scanning signal is a digital voltage signal of H level or L level. When the transistor 40101 is an N-channel type, the H level of the scanning signal is a potential that can turn on the transistor 40101, and the L level of the scanning signal is a potential that can turn off the transistor 40101.
When 0101 is a P-channel type, the H level of the scanning signal is a potential that can turn off the transistor 40101, and the L level of the scanning signal is a potential that can turn on the transistor 40101. Note that the video signal is an analog voltage. However, this is not limited to this, and the video signal may be a digital voltage. Alternatively, the video signal may be a current. The current of this video signal may be either analog or digital. The video signal has a potential that is lower than the H level of the scanning signal and higher than the L level of the scanning signal. Note that it is preferable that the constant potential supplied to the wiring 40106 is equal to the potential of the opposing electrode 40107.

The operation of the pixel 40100 will be described separately for the case where the transistor 40101 is on and the case where the transistor 40101 is off.

When the transistor 40101 is on, the wiring 40104 and the liquid crystal element 40102
A first electrode (pixel electrode) of the liquid crystal element 40102 and a first electrode of the capacitor 40103 are electrically connected to each other. Therefore, a video signal is input from the wiring 40104 through the transistor 40101 to the first electrode (pixel electrode) of the liquid crystal element 40102 and the first electrode of the capacitor 40103.
The capacitor 40103 holds a potential difference between a video signal and a potential supplied to a wiring 40106 .

When the transistor 40101 is off, the wiring 40104 and the liquid crystal element 40102
The first electrode (pixel electrode) of the liquid crystal element 40102 and the first electrode of the capacitor 40103 are electrically disconnected. Therefore, the first electrode of the liquid crystal element 40102 and the first electrode of the capacitor 40103 are in a floating state. Since the capacitor 40103 holds a potential difference between the video signal and the potential supplied to the wiring 40106, the first electrode of the liquid crystal element 40102 and the first electrode of the capacitor 40103 are electrically disconnected.
The electrode maintains a potential equal to (corresponding to) the video signal.
The transmittance corresponds to the video signal.

Fig. 131(B) is a diagram showing an example of a pixel configuration that can be applied to a liquid crystal display device. In particular, Fig. 131(B) is a diagram showing an example of a pixel configuration that can be applied to a liquid crystal display device suitable for a lateral electric field mode (including an IPS mode and an FFS mode).

The pixel 40110 includes a transistor 40111, a liquid crystal element 40112, and a capacitor element 4011
The gate of the transistor 40111 is connected to a wiring 40115.
A first terminal of the transistor 40111 is connected to the wiring 40114.
A second terminal of the capacitor 40111 is connected to a first electrode of a liquid crystal element 40112 and a first electrode of a capacitor 40113. A second electrode of the liquid crystal element 40112 is connected to a wiring 40116. A second electrode of the capacitor 40113 is connected to the wiring 40116.

The wiring 40114 functions as a signal line. The wiring 40115 functions as a scan line. The wiring 40116 functions as a capacitor line. The transistor 40111 functions as a switch. The capacitor 40113 functions as a storage capacitor.

The transistor 40111 is only required to function as a switch, and the polarity of the transistor 40111 may be either a P-channel type or an N-channel type.

A video signal is input to the wiring 40114. A scanning signal is input to the wiring 40115. A certain potential is supplied to the wiring 40116. The scanning signal is a digital voltage signal of H level or L level. When the transistor 40111 is an N-channel type, the H level of the scanning signal is a potential that can turn on the transistor 40111, and the L level of the scanning signal is a potential that can turn off the transistor 40111.
When the transistor 40111 is a P-channel type, the H level of the scanning signal is a potential that can turn off the transistor 40111, and the L level of the scanning signal is a potential that can turn on the transistor 40111. Note that the video signal is an analog voltage. However, this is not limited to this, and the video signal may be a digital voltage. Alternatively, the video signal may be a current. The current of the video signal may be either analog or digital. The video signal is a potential that is lower than the H level of the scanning signal and higher than the L level of the scanning signal.

The operation of the pixel 40110 will be described separately for the case where the transistor 40111 is on and the case where the transistor 40111 is off.

When the transistor 40111 is on, the wiring 40114 and the liquid crystal element 40112
A first electrode (pixel electrode) of the liquid crystal element 40112 and a first electrode of the capacitor 40113 are electrically connected to each other. Therefore, a video signal is input from the wiring 40114 through the transistor 40111 to the first electrode (pixel electrode) of the liquid crystal element 40112 and the first electrode of the capacitor 40113.
The capacitor 40113 holds a potential difference between the video signal and the potential supplied to the wiring 40116 .

When the transistor 40111 is off, the wiring 40114 and the liquid crystal element 40112
The first electrode (pixel electrode) of the liquid crystal element 40112 and the first electrode of the capacitor 40113 are electrically disconnected from each other. Therefore, the first electrode of the liquid crystal element 40112 and the first electrode of the capacitor 40113 are in a floating state. Since the capacitor 40113 holds a potential difference between the video signal and the potential supplied to the wiring 40116, the first electrode of the liquid crystal element 40112 and the first electrode of the capacitor 40113 are electrically disconnected from each other.
The electrode maintains a potential equal to (corresponding to) the video signal.
The transmittance corresponds to the video signal.

FIG. 132 is a diagram showing an example of a pixel configuration that can be applied to a liquid crystal display device.
is an example of a pixel configuration that can reduce the number of wirings and increase the aperture ratio of the pixel.

FIG. 132 shows two pixels (pixel 40200 and pixel 40210) arranged in the same column direction.
For example, when the pixel 40200 is arranged in the Nth row, the pixel 40210 is arranged in the Nth row.
It is placed on the first line.

The pixel 40200 includes a transistor 40201, a liquid crystal element 40202, and a capacitor element 4020.
A gate of the transistor 40201 is connected to a wiring 40205.
A first terminal of the transistor 40201 is connected to the wiring 40204.
A second terminal of the transistor 40201 is connected to a first electrode of a liquid crystal element 40202 and a first electrode of a capacitor element 40203. A second electrode of the liquid crystal element 40202 corresponds to a counter electrode 40207. A second electrode of the capacitor element 40203 is connected to the same wiring as the gate of the transistor in the previous row.

The pixel 40210 includes a transistor 40211, a liquid crystal element 40212, and a capacitor element 4021
A gate of the transistor 40211 is connected to a wiring 40215.
A first terminal of the transistor 40211 is connected to the wiring 40204.
The second terminal of the transistor 40211 is connected to the first electrode of the liquid crystal element 40212 and the first electrode of the capacitor element 40213. The second electrode of the liquid crystal element 40212 corresponds to a counter electrode 40217. The second electrode of the capacitor element 40213 is connected to the same wiring (wiring 40205) as the gate of the transistor in the previous row.
It is connected to the.

The wiring 40204 functions as a signal line. The wiring 40205 functions as a scan line of the Nth row. The wiring 40206 functions as a capacitor line of the Nth row. The transistor 40201 functions as a switch. The capacitor 40203 functions as a storage capacitor.

The wiring 40214 functions as a signal line. The wiring 40215 functions as a scan line in the (N+1)th row. The wiring 40216 functions as a capacitor line in the (N+1)th row.
The capacitor 40211 functions as a switch. The capacitor 40213 functions as a storage capacitor.

The transistor 40201 and the transistor 40211 only need to function as switches.
The polarity of the transistor 40201 and the polarity of the transistor 40211 may be a P-channel type or an N-channel type.

A video signal is input to the wiring 40204. A scanning signal (
A scanning signal (N+1th row) is input to the wiring 40215.

The scanning signal is a digital voltage signal of H level or L level.
When the transistor 40201 (or the transistor 40211) is an N-channel type, the H level of the scanning signal is a potential that can turn on the transistor 40201 (or the transistor 40211), and the L level of the scanning signal is a potential that can turn off the transistor 40201 (or the transistor 40211).
The H level of the scanning signal is a potential that can turn off the transistor 40201 (or the transistor 40211), and the L level of the scanning signal is a potential that can turn off the transistor 40201 (or the transistor 40211).
) can be turned on. The video signal is an analog voltage. However, the present invention is not limited to this, and the video signal may be a digital voltage. Alternatively, the video signal may be a current.
The current of the video signal may be either analog or digital. The video signal has a potential lower than the H level of the scanning signal and higher than the L level of the scanning signal.

The operation of the pixel 40200 will be described separately for the case where the transistor 40201 is on and the case where the transistor 40201 is off.

When the transistor 40201 is on, the wiring 40204 and the liquid crystal element 40202
A first electrode (pixel electrode) of the liquid crystal element 40202 and a first electrode of the capacitor 40203 are electrically connected to each other. Therefore, a video signal is input from the wiring 40204 through the transistor 40201 to the first electrode (pixel electrode) of the liquid crystal element 40202 and the first electrode of the capacitor 40203.
The capacitor 40203 holds a potential difference between a video signal and a potential supplied to the same wiring as the gate of the transistor in the previous row.

When the transistor 40201 is off, the wiring 40204 and the liquid crystal element 40202
The first electrode (pixel electrode) of the liquid crystal element 40202 and the first electrode of the capacitor 40203 are electrically isolated from each other. Therefore, the first electrode of the liquid crystal element 40202 and the first electrode of the capacitor 40203 are in a floating state. Since the capacitor 40203 holds a potential difference between the video signal and a potential supplied to the same wiring as the gate of the transistor in the previous row, the first electrode of the liquid crystal element 40202 and the first electrode of the capacitor 40203 hold a potential that is the same as (corresponding to) the video signal.
The liquid crystal element 40202 has a transmittance according to a video signal.

The operation of the pixel 40210 will be described separately for the case where the transistor 40211 is on and the case where the transistor 40211 is off.

When the transistor 40211 is on, the wiring 40204 and the liquid crystal element 40212
A first electrode (pixel electrode) of the liquid crystal element 40212 and a first electrode of the capacitor 40213 are electrically connected to each other. Therefore, a video signal is input from the wiring 40204 through the transistor 40211 to the first electrode (pixel electrode) of the liquid crystal element 40212 and the first electrode of the capacitor 40213.
The capacitor 40213 holds a potential difference between the video signal and a potential supplied to the same wiring (wiring 40205) as the gate of the transistor in the previous row.

When the transistor 40211 is off, the wiring 40204 and the liquid crystal element 40212
The first electrode (pixel electrode) of the liquid crystal element 40212 and the first electrode of the capacitor 40213 are electrically disconnected from each other. Therefore, the first electrode of the liquid crystal element 40212 and the first electrode of the capacitor 40213 are in a floating state. The capacitor 40213 holds a potential difference between the video signal and a potential supplied to the same wiring (wiring 40205) as the gate of the transistor in the previous row.
The first electrode of the capacitor 40212 and the first electrode of the capacitor element 40213 maintain a potential equal to (corresponding to) the video signal. Note that the transmittance of the liquid crystal element 40212 varies according to the video signal.

FIG. 133 is a diagram showing an example of a pixel configuration that can be applied to a liquid crystal display device.
is an example of a pixel configuration that can improve the viewing angle by using sub-pixels.

The pixel 40320 includes a sub-pixel 40300 and a sub-pixel 40310.
Although a case where pixel 40320 has two sub-pixels will be described, pixel 40320 may have three or more sub-pixels.

The sub-pixel 40300 includes a transistor 40301, a liquid crystal element 40302, and a capacitor element 40
A gate of the transistor 40301 is connected to a wiring 40305. A first terminal of the transistor 40301 is connected to a wiring 40304. A second terminal of the transistor 40301 is connected to a first electrode of a liquid crystal element 40302 and a first electrode of a capacitor 40303.
A second electrode of the liquid crystal element 40302 corresponds to a counter electrode 40307. A second electrode of the capacitor element 40303 is connected to a wiring 40306.

The sub-pixel 40310 includes a transistor 40311, a liquid crystal element 40312, and a capacitor element 40
A gate of the transistor 40311 is connected to a wiring 40315. A first terminal of the transistor 40301 is connected to a wiring 40304. A second terminal of the transistor 40311 is connected to a first electrode of a liquid crystal element 40312 and a first electrode of a capacitor 40313.
A second electrode of the liquid crystal element 40312 corresponds to a counter electrode 40317. A second electrode of the capacitor element 40313 is connected to a wiring 40306.

The wiring 40304 functions as a signal line. The wiring 40305 functions as a scan line. The wiring 40315 functions as a signal line. The wiring 40306 functions as a capacitor line. The transistor 40301 functions as a switch. The transistor 40311 functions as a switch. The capacitor 40303 functions as a storage capacitor. The capacitor 40313 functions as a storage capacitor.

The transistor 40301 is required to function as a switch, and the polarity of the transistor 40301 may be a P-channel type or an N-channel type. The transistor 40311 is required to function as a switch, and the polarity of the transistor 40311 may be a P-channel type or an N-channel type.
It may be of a channel type.

Note that a video signal is input to the wiring 40304. A scanning signal is input to the wiring 40305. A scanning signal is input to the wiring 40315. A certain constant potential is supplied to the wiring 40306.

The scanning signal is a digital voltage signal of H level or L level.
When the transistor 40301 (or the transistor 40311) is an N-channel type, the H level of the scanning signal is a potential that can turn on the transistor 40301 (or the transistor 40311), and the L level of the scanning signal is a potential that can turn off the transistor 40301 (or the transistor 40311). Alternatively, when the transistor 40301 (or the transistor 40311) is a P-channel type, the H level of the scanning signal is a potential that can turn off the transistor 40301 (or the transistor 40311), and the L level of the scanning signal is a potential that can turn off the transistor 40301 (or the transistor 40311).
311) can be turned on. The video signal is an analog voltage. However, the present invention is not limited to this, and the video signal may be a digital voltage. Alternatively, the video signal may be a current. The current of the video signal may be either analog or digital. The video signal is a potential lower than the H level of the scanning signal and higher than the L level of the scanning signal.
The constant potential supplied to the counter electrode 40306 is the potential of the counter electrode 40307 or the counter electrode 4031.
It is preferable that the potential is equal to that of 7.

Regarding the operation of the pixel 40320, the transistor 40301 is turned on and the transistor 4031
The following describes three cases: when the transistor 40301 is off and the transistor 40311 is on; and when both the transistor 40301 and the transistor 40311 are off.

When the transistor 40301 is on and the transistor 40311 is off, in the sub-pixel 40300, the wiring 40304 and the first electrode (pixel electrode) of the liquid crystal element 40302
and the first electrode of the capacitor 40303 are electrically connected. Therefore, a video signal is input from the wiring 40304 through the transistor 40301 to the first electrode (pixel electrode) of the liquid crystal element 40302 and the first electrode of the capacitor 40303.
40303 holds a potential difference between a video signal and a potential supplied to the wiring 40306. At this time, in the sub-pixel 40310,
The pixel electrode and the first electrode of the capacitor 40313 are electrically isolated from each other. Therefore, a video signal is not input to the sub-pixel 40310.

When the transistor 40301 is turned off and the transistor 40311 is turned on, the wiring 40304 is electrically cut off from the first electrode (pixel electrode) of the liquid crystal element 40302 and the first electrode of the capacitor element 40303 in the subpixel 40300.
The first electrode of the capacitor 40302 and the first electrode of the capacitor 40303 are in a floating state.
Since the line 40303 holds a potential difference between the video signal and the potential supplied to the line 40306, the first electrode of the liquid crystal element 40302 and the first electrode of the capacitor element 40303 hold a potential that is the same as (corresponding to) the video signal.
40304 is electrically connected to a first electrode (pixel electrode) of the liquid crystal element 40312 and a first electrode of the capacitor element 40313. Therefore, a video signal is transmitted from the wiring 40304 through the transistor 40311 to the first electrode (pixel electrode) of the liquid crystal element 40312 and the first electrode of the capacitor element 40313.
The video signal is input to the first electrode of the capacitor 40313 and the wiring 40316.
The potential difference between the potential supplied to the

When the transistor 40301 and the transistor 40311 are off, the sub-pixel 4
In the liquid crystal element 40300, the wiring 40304 is electrically isolated from the first electrode (pixel electrode) of the liquid crystal element 40302 and the first electrode of the capacitor element 40303.
The first electrode of the capacitor 40303 and the first electrode of the capacitor 40303 are in a floating state.
Since the potential difference between the video signal and the potential supplied to the wiring 40306 is held, the first electrode of the liquid crystal element 40302 and the first electrode of the capacitor element 40303 are the same as the video signal (
The liquid crystal element 40302 maintains a potential (corresponding to the video signal). Note that the transmittance of the liquid crystal element 40302 corresponds to the video signal. At this time, in the sub-pixel 40310, the wiring 40304 is electrically cut off from the first electrode (pixel electrode) of the liquid crystal element 40312 and the first electrode of the capacitor 40313. Therefore, the first electrode of the liquid crystal element 40312 and the first electrode of the capacitor 40313 are in a floating state. Since the capacitor 40313 holds a potential difference between the video signal and the potential supplied to the wiring 40306, the first electrode of the liquid crystal element 40312 and the capacitor 403
The first electrode 13 maintains a potential equal to (corresponding to) the video signal.
312 is the transmittance according to the video signal.

The video signal input to the sub-pixel 40300 may have a different value from the video signal input to the sub-pixel 40310. In this case, the alignment of the liquid crystal molecules of the liquid crystal element 40302 is changed to that of the liquid crystal element 40310.
Since the orientation of the liquid crystal molecules can be made different from that of the liquid crystal display panel 0312, the viewing angle can be made wider.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 8)
In this embodiment, a method for driving a display device, particularly a method for driving a liquid crystal display device, will be described.

The liquid crystal panel that can be used in the liquid crystal display device described in this embodiment has a structure in which a liquid crystal material is sandwiched between two substrates. Each of the two substrates is provided with an electrode for controlling the electric field applied to the liquid crystal material. The optical and electrical properties of the liquid crystal material change depending on an electric field applied from the outside. Therefore, the liquid crystal panel is
This device can obtain the desired optical and electrical properties by controlling the voltage applied to the liquid crystal material using the electrodes on the substrate. By arranging a large number of electrodes side by side in a plane, each one becomes a pixel, and by individually controlling the voltage applied to the pixel, a liquid crystal panel can be made that can display high-resolution images.

Here, the response time of the liquid crystal material to a change in the electric field is determined by the distance between the two substrates (cell gap)
The response time depends on the type of liquid crystal material, and is generally several milliseconds to several tens of milliseconds. Furthermore, when the change in the electric field is small, the response time of the liquid crystal material becomes even longer. This property causes problems in image display such as afterimages, trailing, and reduced contrast when displaying moving images using a liquid crystal panel, and the degree of the above-mentioned problems becomes particularly severe when changing from one gray level to another (when the change in the electric field is small).

On the other hand, a problem specific to liquid crystal panels using an active matrix is the change in the write voltage due to constant charge driving. The constant charge driving in this embodiment will be described below.

The pixel circuit in an active matrix includes a switch that controls writing and a capacitive element that holds the charge. The method of driving the pixel circuit in an active matrix is to turn the switch on and write a predetermined voltage to the pixel circuit, and then immediately turn the switch off to hold the charge in the pixel circuit (hold state). In the hold state, no charge is exchanged between the inside and outside of the pixel circuit (constant charge). Normally, the period in which the switch is off is several hundred times (the number of scanning lines) longer than the period in which the switch is on. Therefore, the switch of the pixel circuit can be considered to be almost always in the off state.
From the above, the constant charge drive in this embodiment is a drive method in which the pixel circuits are in a hold state for most of the time when the liquid crystal panel is driven.

Next, the electrical properties of liquid crystal materials will be described. When an externally applied electric field changes, the optical properties of liquid crystal materials change, and at the same time, the dielectric constant also changes. In other words, when each pixel of a liquid crystal panel is considered as a capacitive element (liquid crystal element) sandwiched between two electrodes, the capacitive element is a capacitive element whose electrostatic capacitance changes depending on the applied voltage. This phenomenon is called dynamic capacitance.

In this way, when a capacitive element whose capacitance changes depending on the applied voltage is driven by the above-mentioned constant charge driving, the following problem occurs. That is, in the hold state where no charge is transferred, if the capacitance of the liquid crystal element changes, the applied voltage also changes. This can be understood from the fact that the amount of charge is constant in the relational expression (amount of charge) = (capacitance) x (applied voltage).

For the above reasons, in a liquid crystal panel using an active matrix, the voltage in the hold state changes from the voltage during writing due to the constant charge drive. As a result, the transmittance of the liquid crystal element changes differently from that in a drive method that does not adopt a hold state. This is shown in Figure 83. Figure 83(A) shows an example of control of the voltage written to the pixel circuit, with time on the horizontal axis and absolute voltage on the vertical axis. Figure 83(B) shows an example of control of the voltage written to the pixel circuit, with time on the horizontal axis and voltage on the vertical axis. Figure 83(C) shows an example of control of the voltage written to the pixel circuit, with time on the horizontal axis and voltage on the vertical axis.
83(A) or 83(B) is written to a pixel circuit. In FIG. 83(A) to (C), a period F represents a voltage rewrite cycle, and the times at which the voltage is rewritten are _t1 , _t2 , _t3 , _t4 , . . .
・Explain as follows.

Here, the write voltage _{corresponding} to _the image data input to the liquid crystal display device is |V ₁ | in the rewrite _at time 0 _, and |
V ₂ | (see FIG. 83(A)).

The polarity of the write voltage corresponding to the image data input to the liquid crystal display device may be periodically reversed (reversal drive: see FIG. 83(B)). This method can minimize the application of DC voltage to the liquid crystal, thereby preventing burn-in caused by deterioration of the liquid crystal element. The period for reversing the polarity (reversal period) may be the same as the period for rewriting the voltage. In this case, the reversal period is short, so that the occurrence of flicker due to the reversal drive can be reduced. Furthermore, the reversal period may be an integer multiple of the period for rewriting the voltage. In this case, the reversal period is long, so that the frequency of writing the voltage by changing the polarity can be reduced, thereby reducing power consumption.

FIG. 83C shows the time change in the transmittance of the liquid crystal element when the voltage shown in FIG. 83A or FIG. _83B is applied to the liquid crystal element.
The transmittance of the liquid crystal element after a sufficient time has passed since a voltage |V ₂ | is applied to the liquid crystal element is defined as TR _1. Similarly, the transmittance of the liquid crystal element after a sufficient time has passed since a voltage |V 2 | is applied to the liquid crystal element is defined as TR _2. When the voltage applied to the liquid crystal element changes from |V ₁ | to |V ₂ | at time t ₁ , the transmittance of the liquid crystal element does not immediately become TR ₂ , but changes slowly, as shown by the dashed line 30401. For example, when the rewrite period of the voltage is the same as the frame period (16.7 milliseconds) of a 60 Hz image signal, it takes a time of about several frames until the transmittance changes to TR ₂ .

However, the smooth time change of the transmittance as shown by the dashed line 30401 is when a voltage |V ₂ | is accurately applied to the liquid crystal element. In an actual liquid crystal panel, for example, a liquid crystal panel using an active matrix, the voltage in the hold state changes from the voltage at the time of writing due to the constant charge drive, so the transmittance of the liquid crystal element does not change with time as shown by the dashed line 30401, but instead changes stepwise with time as shown by the solid line 30401. This is because the voltage changes due to the constant charge drive, so the target voltage cannot be reached by one writing. As a result, the response time of the transmittance of the liquid crystal element appears to be longer than the original response time (dashed line 30401), which significantly causes image display problems such as afterimages, tailing, and reduced contrast.

By using overdrive driving, it is possible to simultaneously solve the problem of the inherent response time of the liquid crystal element and the phenomenon of the apparent response time being further extended due to insufficient writing caused by dynamic capacitance and constant charge driving. This is shown in FIG. 84. FIG. 84(A) shows an example of control of the voltage written to the pixel circuit, with the horizontal axis representing time and the vertical axis representing the absolute value of the voltage. FIG. 84(B) shows an example of control of the voltage written to the pixel circuit, with the horizontal axis representing time and the vertical axis representing the voltage. FIG. 84(C) shows the time change in the transmittance of the liquid crystal element when the voltage shown in FIG. 84(A) or FIG. 84(B) is written to the pixel circuit, with the horizontal axis representing time and the vertical axis representing the transmittance of the liquid crystal element. In FIG. 84(A) to (C), the period F represents the voltage rewrite period, and the times at which the voltage is rewritten are described as t ₁ , t ₂ , t ₃ , t ₄ , . . .

Here, the write voltages corresponding to the image data input to the liquid crystal display device are |V ₁ | for rewriting at time 0, |V ₃ | for rewriting at time t ₁ , and |V 4 | for rewriting at times t ₂ , t ₃ , and t
In the rewriting in ₄ , ..., it is assumed that |V ₂ | (see FIG. 84(A)).

The polarity of the write voltage corresponding to the image data input to the liquid crystal display device may be periodically reversed (reversal drive: see FIG. 84(B)). This method can minimize the application of DC voltage to the liquid crystal, thereby preventing burn-in caused by deterioration of the liquid crystal element. The period for reversing the polarity (reversal period) may be the same as the voltage rewrite period. In this case, the reversal period is short, so that the occurrence of flicker due to the reversal drive can be reduced. Furthermore, the reversal period may be an integer multiple of the voltage rewrite period. In this case, the reversal period is long, so that the frequency of writing voltage by changing the polarity can be reduced, thereby reducing power consumption.

FIG. 84C shows the time change in the transmittance of the liquid crystal element when the voltage shown in FIG. 84A or FIG. _84B is applied to the liquid crystal element.
The transmittance of the liquid crystal element after a sufficient time has passed after a voltage |V ₂ | is applied to the liquid crystal element is TR _1. Similarly, the transmittance of the liquid crystal element after a sufficient time has passed after a voltage |V _{3 | is applied to the liquid crystal element is TR 3. At time t 1, the voltage applied to the liquid crystal element changes from |V 1 | to |} V
₃ |, the transmittance of the liquid crystal element attempts to change to TR ₃ over several frames as shown by the dashed line 30501. However, the application of the voltage |V ₃ | ends at time _t2 , and after time _t2 , the voltage |V ₂ | is applied. Therefore, the transmittance of the liquid crystal element does not become as shown by the dashed line 30501, but becomes as shown by the solid line 30502. Here,
It is preferable to set the value of the voltage |V ₃ | so that at time t ₂ , the transmittance is approximately TR _2. Here, the voltage |V ₃ | is also called an overdrive voltage.

In other words, by changing the overdrive voltage | _V3 |, it is possible to control the response time of the liquid crystal element to some extent. This is because the response time of the liquid crystal changes depending on the strength of the electric field. Specifically, the stronger the electric field, the shorter the response time of the liquid crystal element, and the weaker the electric field, the longer the response time of the liquid crystal element.

It is preferable to change the overdrive voltage | _V3 | according to the amount of change in voltage, i.e., the voltages | _V1 | and | _V2 | that give the target transmittances _TR1 and _TR2 . This is because even if the response time of the liquid crystal element changes depending on the amount of change in voltage, it is possible to always obtain an optimal response time by changing the overdrive voltage | _V3 | accordingly.

It is preferable to change the overdrive voltage | _V3 | depending on the liquid crystal mode, such as TN, VA, IPS, OCB, etc. This is because even if the response speed of the liquid crystal differs depending on the liquid crystal mode, it is possible to always obtain an optimal response time by changing the overdrive voltage | _V3 | accordingly.

The voltage rewrite period F may be the same as the frame period of the input signal. In this case, the peripheral driving circuits of the liquid crystal display device can be simplified, so that a liquid crystal display device can be obtained at low manufacturing costs.

The voltage rewrite period F may be shorter than the frame period of the input signal. For example,
The voltage rewrite period F may be 1/2, 1/3, or less than the frame period of the input signal. This method is effective when used in conjunction with measures against degradation of moving image quality caused by hold drive of a liquid crystal display device, such as black insertion drive, backlight blinking, backlight scanning, and intermediate image insertion drive by motion compensation. That is, the measures against degradation of moving image quality caused by hold drive of a liquid crystal display device require a short response time of the liquid crystal element, so that the response time of the liquid crystal element can be relatively easily shortened by using the overdrive drive method described in this embodiment. Although it is possible to essentially shorten the response time of a liquid crystal element by using the cell gap, liquid crystal material, liquid crystal mode, etc., it is technically difficult. Therefore, it is very important to use a method such as overdrive that shortens the response time of a liquid crystal element from a drive method.

The voltage rewrite period F may be longer than the frame period of the input signal. For example,
The voltage rewrite period F may be twice, three times, or even more than the frame period of the input signal. This method is effective when used in conjunction with a means (circuit) for determining whether or not the voltage will not be rewritten for a long period of time. In other words, if the voltage will not be rewritten for a long period of time, the operation of the circuit can be stopped during that period by not performing the voltage rewrite operation itself, thereby making it possible to obtain a liquid crystal display device with low power consumption.

Next, a specific method for changing the overdrive voltage |V ₃ | in accordance with the voltages |V ₁ | and |V ₂ | that give the target transmittances TR ₁ and TR ₂ will be described.

The overdrive circuit is a circuit for appropriately controlling the overdrive voltage |V ₃ | in accordance with the voltages |V ₁ | and |V ₂ | that give the target transmittances TR ₁ and TR _2. Therefore, the signal input to the overdrive circuit is _the voltage |V
The signals output from the overdrive circuit are signals related to the overdrive voltage |V ₃ |. Here, these signals include the _voltages (|V ₁ |, |V ₂ |) applied to the liquid crystal element, and the voltage |V ₂ | that gives the transmittance TR ₂ .
, |V ₃ |), or may be a digital signal for applying a voltage to a liquid crystal element. Here, the description will be given assuming that the signal related to the overdrive circuit is a digital signal.

First, the overall configuration of the overdrive circuit will be described with reference to FIG. 80A. Here, the input image signal 301 is used as a signal for controlling the overdrive voltage.
As a result of processing these signals, an output image signal 30104 is output as a signal that provides an overdrive voltage.

Here, the voltages |V ₁ | and |V ₂ | that give the desired transmittances TR ₁ and TR ₂ are given by:
Since the input image signals 30101a and 30101b are image signals in adjacent frames, it is preferable that the input image signals 30101a and 30101b are also image signals in adjacent frames. In order to obtain such a signal, the input image signal 30101a is input to a delay circuit 30102 in FIG. 80A, and the resulting output signal is delayed by the input image signal 3010.
1b. For example, a memory can be used as the delay circuit 30102. That is, in order to delay the input image signal 30101a by one frame, the input image signal 30101a is stored in the memory, and at the same time, the signal stored in the previous frame is taken out from the memory as the input image signal 30101b, and the input image signal 30101a and the input image signal 30101b are simultaneously input to the correction circuit 30103, so that the image signals in adjacent frames can be handled. Then, the image signals in adjacent frames can be input to the correction circuit 30103, so that the output image signal 30104 can be obtained. When a memory is used as the delay circuit 30102, in order to delay by one frame, the memory can be a memory (i.e., a frame memory) having a capacity capable of storing an image signal for one frame. In this way, the delay circuit can function as a delay circuit without excess or deficiency in memory capacity.

Next, a description will be given of the delay circuit 30102 configured mainly for the purpose of reducing the memory capacity. By using such a circuit as the delay circuit 30102, the memory capacity can be reduced, and therefore the manufacturing cost can be reduced.

Specifically, a delay circuit 30102 having such characteristics may be one as shown in Fig. 80(B). The delay circuit 30102 shown in Fig. 80(B) has an encoder 30105, a memory 30106, and a decoder 30107.

The operation of the delay circuit 30102 shown in FIG. 80B is as follows. First, before the input image signal 30101a is stored in the memory 30106, the encoder 3010
The image signal that has been subjected to the compression process is then sent to the encoder 30105, which performs the compression process. This makes it possible to reduce the size of the data to be stored in the memory 30106. As a result, the memory capacity can be reduced, and the manufacturing cost can be reduced. The image signal that has been subjected to the compression process is then sent to the decoder 30107, where it is decompressed.
Here, the encoder 3010 can restore the previous signal that has been compressed by the above.
The compression and expansion processes performed by the encoder 30105 and the decoder 30107 may be lossless processes. In this way, there is no degradation of the image signal even after the compression and expansion processes, so that the memory capacity can be reduced without degrading the quality of the image finally displayed on the device. Furthermore, the compression and expansion processes performed by the encoder 30105 and the decoder 30107 may be lossy processes. In this way, the size of the data of the compressed image signal can be made very small, so that the memory capacity can be significantly reduced.

In addition to the above, various other methods can be used to reduce memory capacity. Instead of compressing images using an encoder, it is possible to reduce the color information contained in the image signal (e.g., reducing the number of colors from 260,000 to 65,000), or to reduce the amount of data (reducing the resolution), etc.

Next, a specific example of the correction circuit 30103 will be described with reference to (C) to (E) of FIG. 80. The correction circuit 30103 is a circuit for outputting an output image signal of a certain value from two input image signals. Here, if the relationship between the two input image signals and the output image signal is nonlinear and difficult to obtain by simple calculation, a look-up table (LUT) may be used as the correction circuit 30103. Since the relationship between the two input image signals and the output image signal is previously obtained by measurement in the LUT, the output image signal corresponding to the two input image signals can be obtained simply by referring to the LUT. (See (C) of FIG. 80) By using the LUT 30108 as the correction circuit 30103, the correction circuit 30103 can be realized without performing complicated circuit design, etc.

Here, since the LUT is one type of memory, it is preferable to reduce the memory capacity as much as possible in terms of reducing manufacturing costs. As an example of a correction circuit 30103 for achieving this, the circuit shown in FIG. 80D is considered. The correction circuit 30103 shown in FIG. 80D
The LUT 30109 has an LUT 30109 and an adder 30110. The LUT 30109 stores difference data between an input image signal 30101a and an output image signal 30104 to be output. That is, the corresponding difference data is extracted from the LUT 30109 from the input image signal 30101a and the input image signal 30101b, and the extracted difference data and the input image signal 30104 are added to the LUT 30109.
101a by an adder 30110, an output image signal 30104 can be obtained.
This can reduce the memory capacity of the UT.
This is because the data size of the difference data is smaller than that of the LUT 30109, and therefore the memory capacity required for the LUT 30109 can be reduced.

Furthermore, if the output image signal can be obtained by a simple calculation such as the four basic arithmetic operations of two input image signals, it can be realized by a combination of simple circuits such as adders, subtractors, and multipliers.
As a result, it becomes unnecessary to use an LUT, and manufacturing costs can be significantly reduced.
An example of such a circuit is shown in FIG.
The correction circuit 30103 shown in FIG. 3E includes a subtractor 30111, a multiplier 30112, and an adder 30113.
0113. First, a subtractor 30111 finds the difference between an input image signal 30101a and an input image signal 30101b. Then, a multiplier 30112 multiplies the difference value by an appropriate coefficient. Then, an adder 30113 adds the difference value multiplied by the appropriate coefficient to the input image signal 30101a, thereby obtaining an output image signal 30104. By using such a circuit, it is no longer necessary to use an LUT, and manufacturing costs can be significantly reduced.

It should be noted that, under certain conditions, it is possible to prevent an inappropriate output image signal 30104 from being output by using the correction circuit 30103 shown in FIG.
The difference between input image signal 30101a and input image signal 30101b has linearity. The slope of this linearity is then used as the coefficient to be multiplied by multiplier 30112. In other words, it is preferable to use correction circuit 30103 shown in FIG. 80E for a liquid crystal element having such properties. An example of a liquid crystal element having such properties is an IPS mode liquid crystal element, the response speed of which has little dependence on gradation. In this way, for example, by using correction circuit 30103 shown in FIG. 80E for an IPS mode liquid crystal element, the manufacturing cost can be significantly reduced,
Moreover, an overdrive circuit capable of preventing the output of an inappropriate output image signal 30104 can be obtained.

In addition, the same function as the circuits shown in (A) to (E) of Fig. 80 may be realized by software processing. The memory used in the delay circuit can be other memory of the liquid crystal display device, or memory of the device that sends out the image to be displayed on the liquid crystal display device (for example, a video card of a personal computer or a similar device). This not only reduces the manufacturing cost, but also allows the user to select the strength of the overdrive and the situation of use according to their preference.

Next, the driving for controlling the potential of the common line will be described with reference to FIG.
81A) is a diagram showing a plurality of pixel circuits when one common line is arranged for one scanning line in a display device using a display element having a capacitive property such as a liquid crystal element. The pixel circuit shown in Fig. 81A includes a transistor 30201, an auxiliary capacitance 30202, a display element 30203, a video signal line 30204, a scanning line 30205, and a common line 30206.

The gate electrode of the transistor 30201 is electrically connected to a scanning line 30205, one of the source electrode and drain electrode of the transistor 30201 is electrically connected to a video signal line 30204, and the other of the source electrode and drain electrode of the transistor 30201 is electrically connected to one electrode of the auxiliary capacitance 30202 and one electrode of the display element 30203.
In addition, the other electrode of the auxiliary capacitance 30202 is electrically connected to a common line 30206 .

First, in a pixel selected by a scanning line 30205, the transistor 30201 is turned on, and thus the display element 30203 and the auxiliary capacitor 3
A voltage corresponding to a video signal is applied to the common line 30.
If all pixels connected to common line 30206 are to display the lowest gradation, or if all pixels connected to common line 30206 are to display the highest gradation, there is no need to write a video signal to each pixel via video signal line 30204.
Instead of writing a video signal through the video signal line 30204 , the voltage applied to the display element 30203 can be changed by changing the potential of the common line 30206 .

Next, Fig. 81B is a diagram showing a plurality of pixel circuits when two common lines are arranged for one scanning line in a display device using a display element having a capacitive property such as a liquid crystal element. The pixel circuit shown in Fig. 81B includes a transistor 30211, an auxiliary capacitance 30212, a display element 30213, a video signal line 30214, a scanning line 30215, a first common line 30216, and a second common line 30217.

The gate electrode of the transistor 30211 is electrically connected to a scanning line 30215, one of the source electrode and drain electrode of the transistor 30211 is electrically connected to a video signal line 30214, and the other of the source electrode and drain electrode of the transistor 30211 is electrically connected to one electrode of the auxiliary capacitance 30212 and one electrode of the display element 30213.
In addition, the other electrode of the auxiliary capacitance 30212 is electrically connected to a first common line 30216 .
In addition, in a pixel adjacent to the pixel in question, the other electrode of the auxiliary capacitance 30212 is electrically connected to a second common line 30217 .

81B, since the number of pixels electrically connected to one common line is small, the frequency with which the voltage applied to the display element 30213 can be changed is significantly increased by changing the potential of the first common line 30216 or the second common line 30217 instead of writing a video signal through the video signal line 30214. In addition, source inversion driving or dot inversion driving becomes possible. By using source inversion driving or dot inversion driving, it is possible to suppress flicker while improving the reliability of the element.

Next, the scanning backlight will be described with reference to Fig. 82. Fig. 82(A) is a diagram showing a scanning backlight in which cold cathode tubes are arranged in a row. The scanning backlight shown in Fig. 82(A) includes a diffusion plate 30301 and N cold cathode tubes 30302-1 to 30302-N. By arranging the N cold cathode tubes 30302-1 to 30302-N in a row behind the diffusion plate 30301, the N cold cathode tubes 30302-1 to 30302-N can be scanned by changing their luminance.

The change in luminance of each cold cathode tube during scanning will be described with reference to FIG. 82C. First, the luminance of the cold cathode tube 30302-1 is changed for a certain period of time. Then, the luminance of the cold cathode tube 30
The luminance of the cold cathode tube 30302-2 arranged next to the cold cathode tube 30302-1 is changed for the same period of time. In this manner, the luminance is changed in order from the cold cathode tube 30302-1 to 30302-N. Note that, although the luminance changed for a certain period of time is set to be smaller than the original luminance in FIG. 82C, it may be larger than the original luminance.
Although scanning is performed up to cold cathode fluorescent tube 30302-N in the above embodiment, scanning may be performed in the reverse direction from cold cathode fluorescent tube 30302-N to 30302-1.

By driving as shown in Fig. 82, it is possible to reduce the average luminance of the backlight, and therefore it is possible to reduce the power consumption of the backlight, which accounts for most of the power consumption of a liquid crystal display device.

Note that LEDs may be used as the light source of the scanning backlight. In that case, the scanning backlight will be as shown in Fig. 82B. The scanning backlight shown in Fig. 82B includes a diffusion plate 30311 and light sources 30312-1 to 30312-N in which LEDs are arranged side by side. When LEDs are used as the light source of the scanning backlight, the backlight can be made thin and
The light source 30312-1 to 30312-N in which LEDs are arranged in parallel has an advantage of being lighter. The light source 30312-1 to 30312-N in which LEDs are arranged in parallel have an advantage of being lighter.
D can also be scanned in the same manner, so that a point-scanning type backlight can also be used.
If a point scanning type is used, the image quality of the moving image can be further improved.

Incidentally, even when an LED is used as the light source of the backlight, it is possible to drive the LED by changing the luminance as shown in FIG.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 9)
In this embodiment, various liquid crystal modes will be described.

First, we will explain the various liquid crystal modes using cross-sectional diagrams.

Figures 134(A) and (B) show schematic diagrams of the cross section of the TN mode.

A liquid crystal layer 50100 is sandwiched between a first substrate 50101 and a second substrate 50102 that are arranged to face each other.
05 is formed on the upper surface of the second substrate 50102. A second electrode 50106 is formed on the upper surface of the second substrate 50102. A first polarizing plate 50103 is disposed on the side of the first substrate 50101 opposite the liquid crystal layer. A second polarizing plate 50104 is disposed on the side of the second substrate 50102 opposite the liquid crystal layer. The first polarizing plate 50103 and the second polarizing plate 50104 are disposed in a crossed Nicol state.

The first polarizing plate 50103 may be disposed on the top surface of the first substrate 50101. The second polarizing plate 50104 may be disposed on the top surface of the second substrate 50102.

At least one (or both) of the first electrode 50105 and the second electrode 50106 may have a light-transmitting property (transmissive or reflective type). Alternatively, both electrodes may have a light-transmitting property and one of the electrodes may have a part of a reflective property (semi-transmissive type).

134A is a schematic diagram of a cross section when a voltage is applied to the first electrode 50105 and the second electrode 50106 (called a vertical electric field method). Since the liquid crystal molecules are vertically aligned, the light from the backlight is not affected by the birefringence of the liquid crystal molecules.
Since the polarizing plate 0103 and the second polarizing plate 50104 are arranged in a crossed Nicol state,
The light from the backlight cannot pass through the substrate, thus producing a black display.

Note that the state of liquid crystal molecules can be controlled by controlling the voltage applied to the first electrode 50105 and the second electrode 50106. Therefore, the amount of light from a backlight that passes through the substrate can be controlled, and a predetermined image can be displayed.

Fig. 134(B) is a schematic diagram of a cross section when no voltage is applied to the first electrode 50105 and the second electrode 50106. Since the liquid crystal molecules are aligned horizontally and rotated in a plane, the light from the backlight is affected by the birefringence of the liquid crystal molecules. Since the first polarizing plate 50103 and the second polarizing plate 50104 are arranged in a crossed Nicol state, the light from the backlight passes through the substrate. Therefore, white display is performed. This is the so-called normally white mode.

The liquid crystal display device having the structure shown in FIG. 134A and FIG. 134B can perform full color display by providing a color filter.
It can be provided on the side or the second substrate 50102 side.

The liquid crystal material used in TN mode can be any known material.

135(A) and (B) are schematic diagrams of the cross section of the VA mode. The VA mode is a mode in which the liquid crystal molecules are aligned perpendicular to the substrate when no electric field is applied.

A liquid crystal layer 50200 is sandwiched between a first substrate 50201 and a second substrate 50202 that are arranged to face each other.
05 is formed on the upper surface of the second substrate 50202. A second electrode 50206 is formed on the upper surface of the second substrate 50202. A first polarizing plate 50203 is disposed on the side of the first substrate 50201 opposite the liquid crystal layer. A second polarizing plate 50204 is disposed on the side of the second substrate 50202 opposite the liquid crystal layer. The first polarizing plate 50203 and the second polarizing plate 50204 are disposed in a crossed Nicol state.

The first polarizing plate 50203 may be disposed on the upper surface of the first substrate 50201. The second polarizing plate 50204 may be disposed on the upper surface of the second substrate 50202.

At least one (or both) of the first electrode 50205 and the second electrode 50206 may have a light-transmitting property (transmissive or reflective type). Alternatively, both electrodes may have a light-transmitting property and one of the electrodes may have a part of a reflective property (semi-transmissive type).

135A is a schematic diagram of a cross section when a voltage is applied to the first electrode 50205 and the second electrode 50206 (called a vertical electric field mode). Since the liquid crystal molecules are aligned horizontally, the light from the backlight is affected by the birefringence of the liquid crystal molecules.
Since the polarizing plate 203 and the second polarizing plate 50204 are arranged in a crossed Nicol state, the light from the backlight passes through the substrate, thereby displaying white color.

Note that the state of liquid crystal molecules can be controlled by controlling the voltage applied to the first electrode 50205 and the second electrode 50206. Therefore, the amount of light from a backlight that passes through the substrate can be controlled, and a predetermined image can be displayed.

135B is a schematic diagram of a cross section when no voltage is applied to the first electrode 50205 and the second electrode 50206. Since the liquid crystal molecules are vertically aligned, the light from the backlight is not affected by the birefringence of the liquid crystal molecules.
Since the polarizing plate 50204 is disposed in a crossed Nicol state, the light from the backlight does not pass through the substrate, and thus a black display is performed. This is the so-called normally black mode.

The liquid crystal display device having the structure shown in FIG. 135A and FIG. 135B can perform full color display by providing a color filter.
It can be provided on the side or the second substrate 50202 side.

The liquid crystal material used in VA mode can be any known material.

135(C) and (D) are schematic diagrams of the cross section of the MVA mode. The MVA mode is a method of mutually compensating for the viewing angle dependence of each part.

A liquid crystal layer 50210 is sandwiched between a first substrate 50211 and a second substrate 50212 that are arranged to face each other.
15 is formed on the upper surface of the second substrate 50212. A second electrode 50216 is formed on the upper surface of the second substrate 50212. A first protrusion 502117 for alignment control is formed on the first electrode 50215. A second protrusion 502118 for alignment control is formed on the second electrode 50216. A first polarizing plate 50213 is formed on the side of the first substrate 50211 opposite to the liquid crystal layer.
A second polarizing plate 5021 is disposed on the opposite side of the second substrate 50212 from the liquid crystal layer.
The first polarizing plate 50213 and the second polarizing plate 50214 are arranged in a crossed Nicol state.

The first polarizing plate 50213 may be disposed on the upper surface of the first substrate 50211. The second polarizing plate 50214 may be disposed on the upper surface of the second substrate 50212.

At least one (or both) of the first electrode 50215 and the second electrode 50216 may have a light-transmitting property (transmissive or reflective type). Alternatively, both electrodes may have a light-transmitting property and one of the electrodes may have a part of a reflective property (semi-transmissive type).

135C is a schematic diagram of a cross section when a voltage is applied to the first electrode 50215 and the second electrode 50216 (called a vertical electric field mode).
and the second protrusion 502118, the light from the backlight is affected by the birefringence of the liquid crystal molecules. And, since the first polarizing plate 50213 and the second polarizing plate 50214 are arranged in a crossed Nicol state, the light from the backlight passes through the substrate. Therefore, white display is performed.

Note that the state of liquid crystal molecules can be controlled by controlling the voltage applied to the first electrode 50215 and the second electrode 50216. Therefore, the amount of light from a backlight that passes through the substrate can be controlled, and a predetermined image can be displayed.

135(D) is a schematic diagram of a cross section when no voltage is applied to the first electrode 50215 and the second electrode 50216. Since the liquid crystal molecules are vertically aligned, the light from the backlight is not affected by the birefringence of the liquid crystal molecules.
Since the polarizing plate 50214 is disposed in a crossed Nicol state, the light from the backlight does not pass through the substrate, and black display is performed. This is the so-called normally black mode.

The liquid crystal display device having the structure shown in FIG. 135C and FIG. 135D can perform full color display by providing a color filter.
It can be provided on the side or the second substrate 50212.

The liquid crystal material used in the MVA mode can be any known material.

Figures 136(A) and (B) show schematic diagrams of the cross section of the OCB mode. In the OCB mode, the alignment of the liquid crystal molecules in the liquid crystal layer forms an optically compensated state, so the viewing angle dependence is small. This state of the liquid crystal molecules is called bend alignment.

A liquid crystal layer 50300 is sandwiched between a first substrate 50301 and a second substrate 50302 that are arranged to face each other. A first electrode 503 is disposed on the upper surface of the first substrate 50301.
05 is formed on the upper surface of the second substrate 50302. A second electrode 50306 is formed on the upper surface of the second substrate 50302. A first polarizing plate 50303 is disposed on the side of the first substrate 50301 opposite the liquid crystal layer. A second polarizing plate 50304 is disposed on the side of the second substrate 50302 opposite the liquid crystal layer. The first polarizing plate 50303 and the second polarizing plate 50304 are disposed in a crossed Nicol state.

The first polarizing plate 50303 may be disposed on the top surface of the first substrate 50301. The second polarizing plate 50304 may be disposed on the top surface of the second substrate 50302.

At least one (or both) of the first electrode 50305 and the second electrode 50306 may have a light-transmitting property (transmissive or reflective type). Alternatively, both electrodes may have a light-transmitting property and one of the electrodes may have a part of a reflective property (semi-transmissive type).

136A is a schematic diagram of a cross section when a voltage is applied to the first electrode 50305 and the second electrode 50306 (called a vertical electric field method). Since the liquid crystal molecules are vertically aligned, the light from the backlight is not affected by the birefringence of the liquid crystal molecules.
Since the first polarizing plate 0303 and the second polarizing plate 50304 are arranged in a crossed Nicol state,
No light from the backlight passes through the substrate, thus producing a black display.

Note that the state of liquid crystal molecules can be controlled by controlling the voltage applied to the first electrode 50305 and the second electrode 50306. Therefore, the amount of light from a backlight that passes through the substrate can be controlled, and a predetermined image can be displayed.

136B is a schematic diagram of a cross section when no voltage is applied to the first electrode 50305 and the second electrode 50306. Since the liquid crystal molecules are in a bend alignment state, the light from the backlight is affected by the birefringence of the liquid crystal molecules.
Since the polarizing plate 50304 is disposed in a crossed Nicol state, the light from the backlight passes through the substrate. Therefore, white display is performed. This is the so-called normally white mode.

The liquid crystal display device having the structure shown in FIG. 136A and FIG. 136B can perform full color display by providing a color filter.
It can be provided on the side or the second substrate 50302 side.

The liquid crystal material used in OCB mode can be any known material.

Figures 136(C) and (D) show schematic cross-sectional views of FLC mode and AFLC mode.

A liquid crystal layer 50310 is sandwiched between a first substrate 50311 and a second substrate 50312 that are arranged to face each other.
15 is formed on the upper surface of the second substrate 50312. A second electrode 50316 is formed on the upper surface of the second substrate 50312. A first polarizing plate 50313 is disposed on the side of the first substrate 50311 opposite the liquid crystal layer. A second polarizing plate 50314 is disposed on the side of the second substrate 50312 opposite the liquid crystal layer. The first polarizing plate 50313 and the second polarizing plate 50314 are disposed in a crossed Nicol state.

The first polarizing plate 50313 may be disposed on the upper surface of the first substrate 50311. The second polarizing plate 50314 may be disposed on the upper surface of the second substrate 50312.

At least one (or both) of the first electrode 50315 and the second electrode 50316 may have a light-transmitting property (transmissive or reflective type). Alternatively, both electrodes may have a light-transmitting property and one of the electrodes may have a part of a reflective property (semi-transmissive type).

Figure 136 (C) is a schematic diagram of a cross section when a voltage is applied to the first electrode 50315 and the second electrode 50316 (called a vertical electric field mode). Since the liquid crystal molecules are aligned horizontally in a direction shifted from the rubbing direction, the light from the backlight is affected by the birefringence of the liquid crystal molecules. Furthermore, since the first polarizing plate 50313 and the second polarizing plate 50314 are arranged in a crossed Nicol state, the light from the backlight passes through the substrate. Therefore,
A white display is performed.

Note that the state of liquid crystal molecules can be controlled by controlling the voltage applied to the first electrode 50315 and the second electrode 50316. Therefore, the amount of light from a backlight that passes through the substrate can be controlled, and a predetermined image can be displayed.

Fig. 136(D) is a schematic diagram of a cross section when no voltage is applied to the first electrode 50315 and the second electrode 50316. Since the liquid crystal molecules are aligned horizontally along the rubbing direction, the light from the backlight is not affected by the birefringence of the liquid crystal molecules. Furthermore, since the first polarizing plate 50313 and the second polarizing plate 50314 are arranged in a cross-Nicol state, the light from the backlight does not pass through the substrate. Therefore, black display is performed. This is the so-called normally black mode.

The liquid crystal display device having the structure shown in FIG. 136C and FIG. 136D can perform full color display by providing a color filter.
It can be provided on the side or the second substrate 50312.

The liquid crystal material used in the FLC mode or AFLC mode may be any known material.

137(A) and (B) show schematic diagrams of the cross section of the IPS mode. The IPS mode is a mode in which the alignment of the liquid crystal molecules in the liquid crystal layer forms an optically compensated state, so that the liquid crystal molecules are always rotated in a plane relative to the substrate, and the electrodes are provided only on one of the substrates, adopting a lateral electric field method.

A liquid crystal layer 50400 is sandwiched between a first substrate 50401 and a second substrate 50402 that are arranged to face each other.
05 and a second electrode 50406 are formed. A first polarizing plate 50403 is disposed on the side of the first substrate 50401 opposite to the liquid crystal layer. A second polarizing plate 50404 is disposed on the side of the second substrate 50402 opposite to the liquid crystal layer. The first polarizing plate 50403 and the second polarizing plate 50404 are disposed in a crossed Nicol state.

The first polarizing plate 50403 may be disposed on the upper surface of the first substrate 50401. The second polarizing plate 50404 may be disposed on the upper surface of the second substrate 50402.

At least one (or both) of the first electrode 50405 and the second electrode 50406 may have a light-transmitting property (transmissive or reflective type). Alternatively, both electrodes may have a light-transmitting property and one of the electrodes may have a part of a reflective property (semi-transmissive type).

137A is a schematic diagram of a cross section when a voltage is applied to the first electrode 50405 and the second electrode 50406 (called a vertical electric field mode). Since the liquid crystal molecules are oriented along electric field lines that are shifted from the rubbing direction, the light from the backlight is affected by the birefringence of the liquid crystal molecules. Since the first polarizing plate 50403 and the second polarizing plate 50404 are arranged in a crossed Nicol state, the light from the backlight passes through the substrate. Therefore, white display is performed.

Note that the state of liquid crystal molecules can be controlled by controlling the voltage applied to the first electrode 50405 and the second electrode 50406. Therefore, the amount of light from a backlight that passes through the substrate can be controlled, and a predetermined image can be displayed.

Fig. 137(B) is a schematic diagram of a cross section when no voltage is applied to the first electrode 50405 and the second electrode 50406. Since the liquid crystal molecules are aligned horizontally along the rubbing direction, the light from the backlight is not affected by the birefringence of the liquid crystal molecules. Furthermore, since the first polarizing plate 50403 and the second polarizing plate 50404 are arranged in a cross-Nicol state, the light from the backlight does not pass through the substrate. Therefore, black display is performed. This is the so-called normally black mode.

The liquid crystal display device having the structure shown in FIG. 137A and FIG. 137B can perform full color display by providing a color filter.
It can be provided on the side or the second substrate 50402 side.

The liquid crystal material used in IPS mode can be any known material.

137(C) and (D) show schematic diagrams of the cross section of the FFS mode. In the FFS mode, the alignment of the liquid crystal molecules in the liquid crystal layer forms an optically compensated state, so the liquid crystal molecules are always rotated in a plane relative to the substrate, and the electrodes are provided only on one of the substrates, adopting a horizontal electric field method.

A liquid crystal layer 50410 is sandwiched between a first substrate 50411 and a second substrate 50412 that are arranged to face each other.
16 is formed on the upper surface of the second electrode 50416. An insulating film 50417 is formed on the upper surface of the second electrode 50416. A second electrode 50416 is formed on the insulating film 50417. A first polarizing plate 50413 is disposed on the side of the first substrate 50411 opposite to the liquid crystal layer. A second polarizing plate 50414 is disposed on the side of the second substrate 50412 opposite to the liquid crystal layer.
The first polarizing plate 50413 and the second polarizing plate 50414 are arranged in a crossed Nicol state.

The first polarizing plate 50413 may be disposed on the upper surface of the first substrate 50411. The second polarizing plate 50414 may be disposed on the upper surface of the second substrate 50412.

At least one (or both) of the first electrode 50415 and the second electrode 50416 may have a light-transmitting property (transmissive or reflective type). Alternatively, both electrodes may have a light-transmitting property and one of the electrodes may have a part of a reflective property (semi-transmissive type).

137C is a schematic diagram of a cross section when a voltage is applied to the first electrode 50415 and the second electrode 50416 (called a vertical electric field mode). Since the liquid crystal molecules are oriented along electric field lines that are shifted from the rubbing direction, the light from the backlight is affected by the birefringence of the liquid crystal molecules. Since the first polarizing plate 50413 and the second polarizing plate 50414 are arranged in a crossed Nicol state, the light from the backlight passes through the substrate. Therefore, white display is performed.

Note that the state of liquid crystal molecules can be controlled by controlling the voltage applied to the first electrode 50415 and the second electrode 50416. Therefore, the amount of light from a backlight that passes through the substrate can be controlled, and a predetermined image can be displayed.

Fig. 137(D) is a schematic diagram of a cross section when no voltage is applied to the first electrode 50415 and the second electrode 50416. Since the liquid crystal molecules are aligned horizontally along the rubbing direction, the light from the backlight is not affected by the birefringence of the liquid crystal molecules. Furthermore, since the first polarizing plate 50413 and the second polarizing plate 50414 are arranged in a crossed Nicol state, the light from the backlight does not pass through the substrate. Therefore, black display is performed. This is the so-called normally black mode.

The liquid crystal display device having the structure shown in FIG. 137C and FIG. 137D can perform full color display by providing a color filter.
It can be provided on the side or the second substrate 50412 side.

The liquid crystal material used in FFS mode can be any known material.

Next, we will explain the various LCD modes using top views.

138 shows a top view of a pixel portion to which the MVA mode is applied. The MVA mode is a method of mutually compensating for the viewing angle dependence of each portion.

FIG. 138 shows a first pixel electrode 50501, a second pixel electrode (50502a, 50502b
, 50502c), and a protrusion 50503. The first pixel electrode 50501 is
The second pixel electrode (50) is formed on the entire surface of the opposing substrate.
The second pixel electrode (502a, 50502b, 50502c) is formed.
The first pixel electrode 5050 corresponds to the first pixel electrode 5050.
A second pixel electrode (50502a, 50502b, 50502c) is formed on the first pixel electrode (50502a, 50502b, 50502c).

The openings in the second pixel electrodes (50502a, 50502b, 50502c) function as protrusions.

A first pixel electrode 50501 and a second pixel electrode (50502a, 50502b, 5050
When a voltage is applied to the second pixel electrode (502c) (called a vertical electric field type), the liquid crystal molecules are
When the pair of polarizing plates are arranged in a crossed Nicol state,
Light from the backlight passes through the substrate, producing a white display.

In addition, the first pixel electrode 50501 and the second pixel electrodes (50502a, 50502b,
By controlling the voltage applied to the liquid crystal display panel 0502c, it is possible to control the state of the liquid crystal molecules. Therefore, it is possible to control the amount of light from the backlight that passes through the substrate, making it possible to display a desired image.

A first pixel electrode 50501 and a second pixel electrode (50502a, 50502b, 5050
2c), when no voltage is applied, the liquid crystal molecules are vertically aligned. When a pair of polarizing plates are arranged in a crossed Nicol configuration, the light from the backlight does not pass through the panel, so black is displayed. This is the so-called normally black mode.

The liquid crystal material used in the MVA mode can be any known material.

139(A), (B), (C), and (D) show top views of a pixel section to which the IPS mode is applied. In the IPS mode, the alignment of the liquid crystal molecules in the liquid crystal layer forms an optically compensated state, so that the liquid crystal molecules are always rotated in a plane relative to the substrate, and the electrodes are provided only on one of the substrates in a lateral electric field manner.

In IPS mode, a pair of electrodes are formed to have different shapes.

139A shows a first pixel electrode 50601 and a second pixel electrode 50602. The first pixel electrode 50601 and the second pixel electrode 50602 have a wave-like shape.

139B shows a first pixel electrode 50611 and a second pixel electrode 50612. The first pixel electrode 50611 and the second pixel electrode 50612 each have a shape having a concentric circular opening.

FIG. 139C shows a first pixel electrode 50631 and a second pixel electrode 50632. The first pixel electrode 50631 and the second pixel electrode 50632 are comb-shaped and partially overlap each other.

139D shows a first pixel electrode 50641 and a second pixel electrode 50642. The first pixel electrode 50641 and the second pixel electrode 50642 are comb-shaped so that the electrodes interdigitate with each other.

First electrodes (50601, 50611, 50621, 50631) and second electrodes (50
When a voltage is applied to the substrates (602, 50612, 50622, 50632) (called a vertical electric field mode), the liquid crystal molecules are oriented along electric field lines that are shifted from the rubbing direction. When a pair of polarizing plates are arranged in a crossed Nicol configuration, light from the backlight passes through the substrates, resulting in a white display.

In addition, it is possible to control the state of the liquid crystal molecules by controlling the voltage applied to the first electrodes (50601, 50611, 50621, 50631) and the second electrodes (50602, 50612, 50622, 50632). Therefore, it is possible to control the amount of light from the backlight that passes through the substrate, and therefore it is possible to display a predetermined image.

First electrodes (50601, 50611, 50621, 50631) and second electrodes (50
When no voltage is applied to the substrates (602, 50612, 50622, 50632), the liquid crystal molecules are aligned horizontally along the rubbing direction. When the pair of polarizing plates are arranged in a cross-Nicol configuration, the light from the backlight does not pass through the substrates, and black is displayed. This is called a normally black mode.

The liquid crystal material used in IPS mode can be any known material.

140(A), (B), (C), and (D) show top views of a pixel section to which the FFS mode is applied. In the FFS mode, the alignment of the liquid crystal molecules in the liquid crystal layer forms an optically compensated state, so that the liquid crystal molecules are always rotated in a plane relative to the substrate, and the electrodes are provided only on one of the substrates in a horizontal electric field manner.

In the FFS mode, a first electrode is formed in various shapes on the upper surface of a second electrode.

FIG. 140A shows a first pixel electrode 50701 and a second pixel electrode 50702. The first pixel electrode 50701 has a bent L-shape. The second pixel electrode 5070
2 may be unpatterned.

140B shows a first pixel electrode 50711 and a second pixel electrode 50712. The first pixel electrode 50711 has a concentric circular shape. The second pixel electrode 50712 does not need to be patterned.

FIG. 140C shows a first pixel electrode 50731 and a second pixel electrode 50732. The first pixel electrode 50731 has a comb-like shape in which the electrodes interdigitate with each other.
The pixel electrode 50732 may not be patterned.

FIG. 140D shows a first pixel electrode 50741 and a second pixel electrode 50742. The first pixel electrode 50741 has a comb-like shape. The second pixel electrode 50742 has a
It does not have to be patterned.

First electrodes (50701, 50711, 50721, 50731) and second electrodes (50
When a voltage is applied to the substrates (702, 50712, 50722, 50732) (called a vertical electric field mode), the liquid crystal molecules are oriented along electric field lines that are shifted from the rubbing direction. When a pair of polarizing plates are arranged in a crossed Nicol configuration, light from the backlight passes through the substrates, resulting in a white display.

In addition, it is possible to control the state of the liquid crystal molecules by controlling the voltage applied to the first electrodes (50701, 50711, 50721, 50731) and the second electrodes (50702, 50712, 50722, 50732). Therefore, it is possible to control the amount of light from the backlight that passes through the substrate, and therefore it is possible to display a predetermined image.

First electrodes (50701, 50711, 50721, 50731) and second electrodes (50
When no voltage is applied to the substrates (702, 50712, 50722, 50732), the liquid crystal molecules are aligned horizontally along the rubbing direction. When a pair of polarizing plates are arranged in a crossed Nicol configuration, the light from the backlight does not pass through the substrates, and black is displayed. This is called a normally black mode.

The liquid crystal material used in IPS mode can be any known material.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 10)
In this embodiment, a pixel structure of a display device, particularly a pixel structure of a liquid crystal display device, will be described.

The pixel structure when each liquid crystal mode and transistor are combined will be described with reference to a cross-sectional view of a pixel.

As the transistor, a thin film transistor (TFT) having a non-single crystal semiconductor layer typified by amorphous silicon, polycrystalline silicon, microcrystalline (also called microcrystal or semi-amorphous) silicon, or the like can be used.

Note that the structure of the transistor can be a top-gate type, a bottom-gate type, etc. Note that the bottom-gate type transistor can be a channel-etched type, a channel-protective type, or the like.

FIG. 85 is an example of a cross-sectional view of a pixel in which the TN method and a transistor are combined.
By applying the pixel structure shown in FIG. 85 to a liquid crystal display device, the liquid crystal display device can be manufactured at low cost.

The characteristics of the pixel structure shown in FIG. 85 will be described. The liquid crystal molecule 10118 shown in FIG.
It is a long and thin molecule with a long axis and a short axis. In order to show the direction of the liquid crystal molecule 10118, it is expressed by its length in FIG. 85. That is, the long liquid crystal molecule 1011
The direction of the long axis of the liquid crystal molecule 10118 is parallel to the paper surface, and the shorter the liquid crystal molecule 10118, the closer the long axis is to the normal direction of the paper surface. In other words, the liquid crystal molecules 10118 shown in FIG. 85 have long axis directions that differ by 90 degrees between those close to the first substrate 10101 and those close to the second substrate 10116.
The long axis of the liquid crystal molecules 10118 shown in FIG. 85 is aligned in a 90 degree direction between the first substrate 10101 and the second substrate 10116.
The orientation is such that it appears to be twisted at 30 degrees.

Note that a case where a bottom-gate transistor using an amorphous semiconductor is used as the transistor will be described. When a transistor using an amorphous semiconductor is used, a liquid crystal display device can be manufactured at low cost using a large-area substrate.

A liquid crystal display device has a key component for displaying images, called a liquid crystal panel. A liquid crystal panel is made by bonding two processed substrates together with a gap of several micrometers between them.
It is made by injecting a liquid crystal material between two substrates. In FIG. 85, the two substrates are:
The first substrate 10101 and the second substrate 10116 are provided with transistors and pixel electrodes. The second substrate 10116 is provided with a light-shielding film 10114 and a color filter 101.
15, a fourth conductive layer 10113, a spacer 10117, and a second alignment film 10112 are formed.

The light-shielding film 10114 may not be formed on the second substrate 10116.
In the case where the light-shielding film 1011 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved.
When the second insulating layer 4 is formed, a display device with little light leakage during black display can be obtained.

It is to be noted that the color filter 10115 does not necessarily have to be formed on the second substrate 10116 .
When the color filter 10115 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved. However, even when the color filter 10115 is not formed, a display device capable of color display by field sequential driving can be obtained. On the other hand, when the color filter 10115 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced.
When forming the display device 5, a display device capable of color display can be obtained.

Note that instead of the spacers 10117, spherical spacers may be dispersed. In the case of dispersing spherical spacers, the number of steps is reduced, so that the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved. On the other hand, in the case of forming the spacers 10117, the position of the spacers does not vary, so that the distance between the two substrates can be made uniform, and a display device with less display unevenness can be obtained.

The processing performed on the first substrate 10101 will be described.

First, a first insulating film 10102 is formed on a first substrate 10101 by a sputtering method, a printing method, a coating method, or the like. However, the first insulating film 10102 does not necessarily have to be formed. The first insulating film 10102 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the properties of the transistor.

Next, a first conductive layer 10103 is formed on the first insulating film 10102 by photolithography.
It is formed by a laser direct drawing method, an ink jet method, or the like.

Next, a second insulating film 10104 is formed on the entire surface by a sputtering method, a printing method, a coating method, or the like. The second insulating film 10104 prevents impurities from the substrate from affecting the semiconductor layer,
It has the function of preventing the properties of the transistor from changing.

Next, a first semiconductor layer 10105 and a second semiconductor layer 10106 are formed. Note that the first semiconductor layer 10105 and the second semiconductor layer 10106 are formed successively and are simultaneously processed into their shapes.

Next, the second conductive layer 10107 is formed by photolithography, laser direct drawing, inkjet printing, or the like. It is preferable to use dry etching as an etching method for processing the shape of the second conductive layer 10107.
The second conductive layer 10107 may be formed using a transparent material or a reflective material.

Next, a channel region of a transistor is formed. An example of the process will be described. The second semiconductor layer 10106 is etched using the second conductive layer 10107 as a mask. Alternatively, the second semiconductor layer 10106 is etched using a mask for processing the shape of the second conductive layer 10107. Then, the first conductive layer 10103 in the portion from which the second semiconductor layer 10106 has been removed becomes a transistor and a channel region. This can reduce the number of masks, thereby reducing manufacturing costs.

Next, a third insulating film 10108 is formed, and a contact hole is selectively formed in the third insulating film 10108. Note that a contact hole may be formed in the second insulating film 10104 at the same time as the contact hole is formed in the third insulating film 10108.
It is preferable that the surface of the third insulating film 10108 is as flat as possible, because the alignment of the liquid crystal molecules is affected by the unevenness of the surface that comes into contact with the liquid crystal.

Next, a third conductive layer 10109 is formed by photolithography, laser direct writing, ink-jet printing, or the like.

Next, a first alignment film 10110 is formed. After the first alignment film 10110 is formed,
Rubbing may be performed to control the alignment of the liquid crystal molecules. Rubbing is a process in which lines are created in the alignment film by rubbing the alignment film with a cloth. By rubbing, the alignment film can be made to have an alignment property.

The first substrate 10101, the light-shielding film 10114, and the color filter 10102 are formed as described above.
The second substrate 10116 on which the second alignment film 10112, the fourth conductive layer 10113, the spacer 10117, and the second alignment film 10112 are formed is attached to the second substrate 10116 with a gap of several micrometers by a sealant. Then, liquid crystal material is injected between the two substrates. In the TN method, the fourth conductive layer 10113 is formed on the entire surface of the second substrate 10116.

FIG. 86(A) shows the MVA (Multi-domain Vertical Alignment)
FIG. 86 is an example of a cross-sectional view of a pixel in the case where the ent type is combined with a transistor.
By applying the pixel structure shown in (A) to a liquid crystal display device, it is possible to obtain a liquid crystal display device having a wide viewing angle, a fast response speed, and a high contrast.

The characteristics of the pixel structure shown in Fig. 86(A) will be described. The characteristics of the pixel structure of the MVA type liquid crystal panel will be described. The liquid crystal molecule 10218 shown in Fig. 86(A) is a long and thin molecule having a long axis and a short axis. In order to show the direction of the liquid crystal molecule 10218, it is expressed by its length in Fig. 86(A). That is, the liquid crystal molecule 10218 expressed as long,
The direction of the long axis is parallel to the paper surface, and the shorter the liquid crystal molecule 10218, the closer the direction of the long axis is to the normal direction of the paper surface. In other words, the liquid crystal molecule 10218 shown in Figure 86 (A) is aligned so that the direction of the long axis is the normal direction of the alignment film. Therefore, the liquid crystal molecule 10218 in the part where the alignment control protrusion 10219 is located is aligned so that the direction of the long axis is parallel to the normal direction of the alignment film.
The molecules are aligned radially from the center 19. In this state, a liquid crystal display device with a wide viewing angle can be obtained.

Note that a case where a bottom-gate transistor using an amorphous semiconductor is used as the transistor will be described. When a transistor using an amorphous semiconductor is used, a liquid crystal display device can be manufactured at low cost using a large-area substrate.

A liquid crystal display device has a key component for displaying images, called a liquid crystal panel. A liquid crystal panel is made by bonding two processed substrates together with a gap of several micrometers between them.
The liquid crystal display is fabricated by injecting a liquid crystal material between two substrates. In Fig. 86(A), the two substrates are a first substrate 10201 and a second substrate 10216. The first substrate has a transistor and a pixel electrode formed thereon. The second substrate has a light-shielding film 10214, a color filter 10215, a fourth conductive layer 10213, a spacer 10217, a second alignment film 1021, and a second conductive layer 1021.
2, and a protrusion 10219 for alignment control is formed.

The light-shielding film 10214 may not be formed on the second substrate 10216.
In the case where the light-shielding film 1021 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved.
When the second insulating layer 4 is formed, a display device with little light leakage during black display can be obtained.

It is to be noted that the color filter 10215 does not necessarily have to be formed on the second substrate 10216 .
When the color filter 10215 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved. However, even if the color filter 10215 is not formed, a display device capable of color display by field sequential driving can be obtained. On the other hand, when the color filter 10215 is not formed,
When forming the display device 5, a display device capable of color display can be obtained.

Note that instead of the spacers 10217, spherical spacers may be dispersed on the second substrate 10216. In the case of dispersing spherical spacers, the number of steps is reduced, so that the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved.
When the spacers 10217 are formed, the positions of the spacers do not vary, so that the distance between the two substrates can be made uniform, and a display device with little display unevenness can be obtained.

The processing performed on the first substrate 10201 is explained below.

First, a first insulating film 10202 is formed on a first substrate 10201 by a sputtering method, a printing method, a coating method, or the like. However, the first insulating film 10202 does not necessarily have to be formed. The first insulating film 10202 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the properties of the transistor.

Next, a first conductive layer 10203 is formed on the first insulating film 10202 by photolithography.
It is formed by a laser direct drawing method, an ink jet method, or the like.

Next, a second insulating film 10204 is formed on the entire surface by a sputtering method, a printing method, a coating method, or the like. The second insulating film 10204 prevents impurities from the substrate from affecting the semiconductor layer,
It has the function of preventing the properties of the transistor from changing.

Next, a first semiconductor layer 10205 and a second semiconductor layer 10206 are formed. Note that the first semiconductor layer 10205 and the second semiconductor layer 10206 are formed successively, and their shapes are processed at the same time.

Next, the second conductive layer 10207 is formed by photolithography, laser direct drawing, inkjet printing, or the like. It is preferable to use dry etching as an etching method for processing the shape of the second conductive layer 10207.
The second conductive layer 10207 may be made of a transparent material or a reflective material.

Next, a channel region of a transistor is formed. An example of the process will be described. The second semiconductor layer 10206 is etched using the second conductive layer 10207 as a mask. Alternatively, the second semiconductor layer 10206 is etched using a mask for processing the shape of the second conductive layer 10207. Then, the first conductive layer 10203 in the portion from which the second semiconductor layer 10206 has been removed becomes a transistor and a channel region. This can reduce the number of masks, thereby reducing manufacturing costs.

Next, a third insulating film 10208 is formed, and a contact hole is selectively formed in the third insulating film 10208. Note that a contact hole may be formed in the second insulating film 10204 at the same time as the contact hole is formed in the third insulating film 10208.

Next, a third conductive layer 10209 is formed by photolithography, laser direct writing, ink-jet printing, or the like.

Next, a first alignment film 10210 is formed. After the first alignment film 10210 is formed,
Rubbing may be performed to control the alignment of the liquid crystal molecules. Rubbing is a process in which lines are created in the alignment film by rubbing the alignment film with a cloth. By rubbing, the alignment film can be made to have an alignment property.

The first substrate 10201, the light-shielding film 10214, and the color filter 10202 thus prepared are then stacked.
The second substrate 10216 on which the MVA 215, the fourth conductive layer 10213, the spacer 10217, and the second alignment film 10212 are formed is attached to the second substrate 10216 with a gap of several micrometers by a sealant. Then, a liquid crystal material is injected between the two substrates.
In this method, the fourth conductive layer 10213 is formed on the entire surface of the second substrate 10216 .
In addition, a protrusion for alignment control 10219 is formed in contact with the fourth conductive layer 10213 .
The shape of the alignment control protrusion 10219 preferably has a smoothly curved surface.
In this way, the alignment of adjacent liquid crystal molecules 10218 becomes very close, so that alignment defects can be reduced, and defects in the alignment film caused by discontinuities in the alignment film can be reduced.

FIG. 86(B) shows PVA (Patterned Vertical Alignment).
86(B) is an example of a cross-sectional view of a pixel in the case where a pixel structure in which a pixel electrode is disposed on a substrate and a transistor is combined with the pixel structure in FIG. 86(B), a liquid crystal display device having a wide viewing angle, a high response speed, and a high contrast can be obtained.

The characteristics of the pixel structure shown in FIG. 86(B) will be described.
Liquid crystal molecule 10248 is a long, thin molecule with a long axis and a short axis. In order to indicate the orientation of liquid crystal molecule 10248, it is expressed by its length in Fig. 86(B). That is, the longer liquid crystal molecule 10248 is expressed, the longer its long axis is parallel to the paper surface, and the shorter the liquid crystal molecule 10248 is expressed, the closer its long axis is to the normal direction to the paper surface. In other words, liquid crystal molecule 10248 shown in Fig. 86(B) is oriented so that its long axis is oriented in the normal direction to the alignment film. Therefore, liquid crystal molecule 10248 in the part with electrode cutout 10249
are oriented radially from the boundary between the electrode cutout portion 10249 and the fourth conductive layer 10243. In this state, a liquid crystal display device with a wide viewing angle can be obtained.

Note that a case where a bottom-gate transistor using an amorphous semiconductor is used as the transistor will be described. When a transistor using an amorphous semiconductor is used, a liquid crystal display device can be manufactured at low cost using a large-area substrate.

A liquid crystal display device has a key component for displaying images, called a liquid crystal panel. A liquid crystal panel is made by bonding two processed substrates together with a gap of several micrometers between them.
The liquid crystal display is fabricated by injecting a liquid crystal material between two substrates. In Fig. 86(B), the two substrates are a first substrate 10231 and a second substrate 10246. The first substrate has a transistor and a pixel electrode formed thereon. The second substrate has a light-shielding film 10244, a color filter 10245, a fourth conductive layer 10243, a spacer 10247, and a second alignment film 10248.
0242 is formed.

The light-shielding film 10244 may not be formed on the second substrate 10246.
In the case where the light-shielding film 1024 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved.
When the second insulating layer 4 is formed, a display device with little light leakage during black display can be obtained.

It is to be noted that the color filter 10245 does not necessarily have to be formed on the second substrate 10246 .
When the color filter 10245 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved. However, even if the color filter 10245 is not formed, a display device capable of color display by field sequential driving can be obtained. On the other hand, when the color filter 10245 is not formed,
When forming the display device 5, a display device capable of color display can be obtained.

Note that instead of the spacers 10247, spherical spacers may be dispersed on the second substrate 10246. In the case of dispersing spherical spacers, the number of steps is reduced, so that the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved.
When the spacers 10247 are formed, the positions of the spacers do not vary, so that the distance between the two substrates can be made uniform, and a display device with less display unevenness can be obtained.

The processing performed on the first substrate 10231 is explained below.

First, a first insulating film 10232 is formed on a first substrate 10231 by a sputtering method, a printing method, a coating method, or the like. However, the first insulating film 10232 does not necessarily have to be formed. The first insulating film 10232 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the properties of the transistor.

Next, a first conductive layer 10233 is formed on the first insulating film 10232 by photolithography.
It is formed by a laser direct drawing method, an ink jet method, or the like.

Next, a second insulating film 10234 is formed on the entire surface by a sputtering method, a printing method, a coating method, or the like. The second insulating film 10234 prevents impurities from the substrate from affecting the semiconductor layer,
It has the function of preventing the properties of the transistor from changing.

Next, a first semiconductor layer 10235 and a second semiconductor layer 10236 are formed. Note that the first semiconductor layer 10235 and the second semiconductor layer 10236 are formed successively, and their shapes are processed at the same time.

Next, the second conductive layer 10237 is formed by photolithography, laser direct drawing, inkjet printing, or the like. It is preferable to use dry etching as an etching method for processing the shape of the second conductive layer 10237.
The second conductive layer 10237 may be made of a transparent material or a reflective material.

Next, a channel region of a transistor is formed. An example of the process will be described. The second semiconductor layer 10236 is etched using the second conductive layer 10237 as a mask. Alternatively, the second semiconductor layer 10236 is etched using a mask for processing the shape of the second conductive layer 10237. Then, the first conductive layer 10233 in the portion from which the second semiconductor layer 10236 has been removed becomes a transistor and a channel region. This can reduce the number of masks, thereby reducing manufacturing costs.

Next, a third insulating film 10238 is formed, and a contact hole is selectively formed in the third insulating film 10238. Note that a contact hole may be formed in the second insulating film 10234 at the same time as the contact hole is formed in the third insulating film 10238.
It is preferable that the surface of the third insulating film 10238 is as flat as possible, because the alignment of the liquid crystal molecules is affected by the unevenness of the surface that contacts the liquid crystal.

Next, a third conductive layer 10239 is formed by photolithography, laser direct writing, ink-jet printing, or the like.

Next, a first alignment film 10240 is formed. After the first alignment film 10240 is formed,
Rubbing may be performed to control the alignment of the liquid crystal molecules. Rubbing is a process in which lines are created in the alignment film by rubbing the alignment film with a cloth. By rubbing, the alignment film can be made to have an alignment property.

The first substrate 10231, the light-shielding film 10244, and the color filter 10
The second substrate 10246 on which the second alignment film 10242, the fourth conductive layer 10243, the spacer 10247, and the second alignment film 10242 are formed is attached to the second substrate 10246 with a gap of several micrometers by a sealant. Then, a liquid crystal material is injected between the two substrates.
In this method, the fourth conductive layer 10243 is patterned to form an electrode cutout portion 10249.
The shape of the electrode cutout 10249 is not limited, but a shape that combines a plurality of rectangles with different orientations is preferable. In this way, a plurality of regions with different orientations can be formed, and a liquid crystal display device with a wide viewing angle can be obtained. Note that the fourth conductive layer 10243 at the boundary between the electrode cutout 10249 and the fourth conductive layer 10243 is preferably a rectangular shape.
The shape of the second alignment film 10243 is preferably a smooth curve. In this way, the alignment of adjacent liquid crystal molecules 10248 becomes very close to each other, thereby reducing alignment defects.
It is also possible to reduce defects in the alignment film caused by a step in the electrode 242 due to the electrode cutout portion 10249.

87A is an example of a cross-sectional view of a pixel in the case where an IPS (In-Plane-Switching) system and a transistor are combined. By applying the pixel structure shown in FIG. 87A to a liquid crystal display device, a liquid crystal display device having a wide viewing angle and a small grayscale dependency of response speed can be obtained in principle.

The characteristics of the pixel structure shown in FIG. 87(A) will be described.
0318 is a long and thin molecule having a long axis and a short axis. In order to show the orientation of the liquid crystal molecule 10318, it is expressed by its length in FIG. 87(A). That is, the liquid crystal molecule 10318 expressed longer has its long axis oriented parallel to the paper surface, and the shorter the liquid crystal molecule 10318 expressed, the closer its long axis is to the normal direction of the paper surface. That is, the liquid crystal molecule 10318 shown in FIG. 87(A) is oriented so that its long axis always faces the direction parallel to the substrate. Although FIG. 87(A) shows the orientation in a state where there is no electric field, when an electric field is applied to the liquid crystal molecule 10318, its long axis always rotates in the horizontal plane while maintaining the direction parallel to the substrate. By achieving this state, a liquid crystal display device with a large viewing angle can be obtained.

Note that a case where a bottom-gate transistor using an amorphous semiconductor is used as the transistor will be described. When a transistor using an amorphous semiconductor is used, a liquid crystal display device can be manufactured at low cost using a large-area substrate.

A liquid crystal display device has a key component for displaying images, called a liquid crystal panel. A liquid crystal panel is made by bonding two processed substrates together with a gap of several micrometers between them.
It is manufactured by injecting a liquid crystal material between two substrates. In Fig. 87(A), the two substrates are a first substrate 10301 and a second substrate 10316. A transistor and a pixel electrode are formed on the first substrate. A light-shielding film 10314, a color filter 10315, a spacer 10317, and a second alignment film 10312 are formed on the second substrate.

The light-shielding film 10314 may not be formed on the second substrate 10316.
In the case where the light-shielding film 1031 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved.
When the second insulating layer 4 is formed, a display device with little light leakage during black display can be obtained.

It is to be noted that the color filter 10315 does not necessarily have to be formed on the second substrate 10316 .
When the color filter 10315 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced. However, even when the color filter 10315 is not formed, a display device capable of color display by field sequential driving can be obtained. Since the structure is simple, the yield can be improved.
When forming the display device 5, a display device capable of color display can be obtained.

Note that instead of the spacers 10317, spherical spacers may be dispersed on the second substrate 10316. In the case of dispersing spherical spacers, the number of steps is reduced, so that the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved.
When the spacers 10317 are formed, the positions of the spacers do not vary, so that the distance between the two substrates can be made uniform, and a display device with little display unevenness can be obtained.

The processing performed on the first substrate 10301 is explained below.

First, a first insulating film 10302 is formed on a first substrate 10301 by a sputtering method, a printing method, a coating method, or the like. However, the first insulating film 10302 does not necessarily have to be formed. The first insulating film 10302 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the properties of the transistor.

Next, a first conductive layer 10303 is formed on the first insulating film 10302 by photolithography.
It is formed by a laser direct drawing method, an ink jet method, or the like.

Next, a second insulating film 10304 is formed on the entire surface by a sputtering method, a printing method, a coating method, or the like. The second insulating film 10304 prevents impurities from the substrate from affecting the semiconductor layer,
It has the function of preventing the properties of the transistor from changing.

Next, a first semiconductor layer 10305 and a second semiconductor layer 10306 are formed. Note that the first semiconductor layer 10305 and the second semiconductor layer 10306 are formed successively, and their shapes are processed at the same time.

Next, the second conductive layer 10307 is formed by photolithography, laser direct drawing, inkjet printing, or the like. It is preferable to use dry etching as an etching method for processing the shape of the second conductive layer 10307.
The second conductive layer 10307 may be made of a transparent material or a reflective material.

Next, a channel region of a transistor is formed. An example of the process will be described. The second semiconductor layer 10306 is etched using the second conductive layer 10307 as a mask. Alternatively, the second semiconductor layer 10306 is etched using a mask for processing the shape of the second conductive layer 10307. Then, the first conductive layer 10303 in the portion from which the second semiconductor layer 10306 has been removed becomes a transistor and a channel region. This can reduce the number of masks, thereby reducing manufacturing costs.

Next, a third insulating film 10308 is formed, and a contact hole is selectively formed in the third insulating film 10308. Note that a contact hole may be formed in the second insulating film 10304 at the same time as the contact hole is formed in the third insulating film 10308.

Next, a third conductive layer 10309 is formed by photolithography, laser direct writing, inkjet, or the like. Here, the shape of the third conductive layer 10309 is two interdigitated comb-like electrodes. One comb-like electrode is electrically connected to one of the source electrode and drain electrode of the transistor, and the other comb-like electrode is electrically connected to the common electrode. In this way, a lateral electric field can be effectively applied to the liquid crystal molecules 10318.

Next, a first alignment film 10310 is formed. After the first alignment film 10310 is formed,
Rubbing may be performed to control the alignment of the liquid crystal molecules. Rubbing is a process in which lines are created in the alignment film by rubbing the alignment film with a cloth. By rubbing, the alignment film can be made to have an alignment property.

The first substrate 10301, the light-shielding film 10314, and the color filter 10
The substrate 315, the spacer 10317, and the second alignment film 10312 are attached together with a sealant with a gap of several micrometers between them. Then, a liquid crystal material is injected between the two substrates.

Fig. 87(B) is an example of a cross-sectional view of a pixel in the case where a FFS (Fringe Field Switching) system and a transistor are combined. By applying the pixel structure shown in Fig. 87(B) to a liquid crystal display device, it is possible to obtain a liquid crystal display device having a wide viewing angle and a small grayscale dependency of the response speed in principle.

The characteristics of the pixel structure shown in FIG. 89(B) will be described.
0348 is a long and thin molecule having a long axis and a short axis. In order to show the orientation of the liquid crystal molecule 10348, it is expressed by its length in FIG. 89(B). That is, the liquid crystal molecule 10348 expressed longer has its long axis oriented parallel to the paper surface, and the shorter the liquid crystal molecule 10348 expressed, the closer its long axis is to the normal direction of the paper surface. That is, the liquid crystal molecule 10348 shown in FIG. 89(B) is oriented so that its long axis always faces the direction parallel to the substrate. Although FIG. 89(B) shows the orientation in a state where there is no electric field, when an electric field is applied to the liquid crystal molecule 10348, its long axis always rotates in the horizontal plane while maintaining the direction parallel to the substrate. By achieving this state, a liquid crystal display device with a large viewing angle can be obtained.

Note that a case where a bottom-gate transistor using an amorphous semiconductor is used as the transistor will be described. When a transistor using an amorphous semiconductor is used, a liquid crystal display device can be manufactured at low cost using a large-area substrate.

A liquid crystal display device has a key component for displaying images, called a liquid crystal panel. A liquid crystal panel is made by bonding two processed substrates together with a gap of several micrometers between them.
The liquid crystal display is fabricated by injecting a liquid crystal material between two substrates. In Fig. 89(B), the two substrates are a first substrate 10331 and a second substrate 10346. The first substrate has a transistor and a pixel electrode formed thereon, and the second substrate has a light-shielding film 10344, a color filter 10350, and a pixel electrode formed thereon.
0345, a spacer 10347, and a second alignment film 10342 are formed.

The light-shielding film 10344 may not be formed on the second substrate 10346.
In the case where the light-shielding film 1034 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved.
When the second insulating layer 4 is formed, a display device with little light leakage during black display can be obtained.

It is to be noted that the color filter 10345 does not necessarily have to be formed on the second substrate 10346 .
When the color filter 10345 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved. However, even when the color filter 10345 is not formed, a display device capable of color display by field sequential driving can be obtained. On the other hand, when the color filter 10345 is not formed, the number of steps is reduced, and therefore the manufacturing cost can be reduced.
When forming the display device 5, a display device capable of color display can be obtained.

Note that instead of the spacers 10347, spherical spacers may be dispersed on the second substrate 10346. In the case of dispersing spherical spacers, the number of steps is reduced, so that the manufacturing cost can be reduced. Since the structure is simple, the yield can be improved.
When the spacers 10347 are formed, the positions of the spacers do not vary, so that the distance between the two substrates can be made uniform, and a display device with little display unevenness can be obtained.

The processing performed on the first substrate 10331 is explained below.

First, a first insulating film 10332 is formed on a first substrate 10331 by a sputtering method, a printing method, a coating method, or the like. However, the first insulating film 10332 does not necessarily have to be formed. The first insulating film 10332 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the properties of the transistor.

Next, a first conductive layer 10333 is formed on the first insulating film 10332 by photolithography.
It is formed by a laser direct drawing method, an ink jet method, or the like.

Next, a second insulating film 10334 is formed on the entire surface by a sputtering method, a printing method, a coating method, or the like. The second insulating film 10334 prevents impurities from the substrate from affecting the semiconductor layer,
It has the function of preventing the properties of the transistor from changing.

Next, a first semiconductor layer 10335 and a second semiconductor layer 10336 are formed. Note that the first semiconductor layer 10335 and the second semiconductor layer 10336 are formed successively, and their shapes are processed at the same time.

Next, the second conductive layer 10337 is formed by photolithography, laser direct drawing, inkjet printing, or the like. It is preferable to use dry etching as an etching method for processing the shape of the second conductive layer 10337.
The second conductive layer 10337 may be made of a transparent material or a reflective material.

Next, a channel region of a transistor is formed. An example of the process will be described. The second semiconductor layer 10336 is etched using the second conductive layer 10337 as a mask. Alternatively, the second semiconductor layer 10336 is etched using a mask for processing the shape of the second conductive layer 10337. Then, the first conductive layer 10333 in the portion from which the second semiconductor layer 10336 has been removed becomes a transistor and a channel region. This can reduce the number of masks, thereby reducing manufacturing costs.

Next, a third insulating film 10338 is formed, and contact holes are selectively formed in the third insulating film 10338 .

Next, a fourth conductive layer 10343 is formed by photolithography, laser direct writing, ink jet printing, or the like.

Next, a fourth insulating film 10349 is formed, and contact holes are selectively formed in the fourth insulating film 10349. It is preferable that the surface of the fourth insulating film 10349 is as flat as possible, because the alignment of the liquid crystal molecules is affected by the unevenness of the surface that contacts the liquid crystal.

Next, a third conductive layer 10339 is formed by photolithography, laser direct writing, ink-jet printing, etc. Here, the shape of the third conductive layer 10339 is a comb shape.

Next, a first alignment film 10340 is formed. After the first alignment film 10340 is formed,
Rubbing may be performed to control the alignment of the liquid crystal molecules. Rubbing is a process in which lines are created in the alignment film by rubbing the alignment film with a cloth. By rubbing, the alignment film can be made to have an alignment property.

The first substrate 10331, the light-shielding film 10344, and the color filter 10
The substrate 345, the spacer 10347, and the second alignment film 10342 are attached with a sealant with a gap of several micrometers, and a liquid crystal material is injected between the two substrates, thereby manufacturing a liquid crystal panel.

Here, we will explain the materials that can be used for each conductive layer or each insulating film.

The first insulating film 10102 in FIG. 85, the first insulating film 10202 in FIG. 86(A),
87(A), the first insulating film 10302 in FIG. 87(A), and the first insulating film 10332 in FIG. 87(B) may be an insulating film such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film (SiOxNy).
For 02, an insulating film having a laminated structure in which two or more films selected from a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiOxNy), and the like are combined can be used.

The first conductive layer 10103 in FIG. 85, the first conductive layer 10203 in FIG. 86(A),
87(A), the first conductive layer 10303 in FIG. 87(A), and the first conductive layer 10333 in FIG. 87(B) are made of Mo, Ti,
, Al, Nd, Cr, etc. can be used. Alternatively, Mo, Ti, Al, Nd, C
A laminated structure in which two or more of the above-mentioned materials are combined may also be used.

The second insulating film 10104 in FIG. 85, the second insulating film 10204 in FIG.
87(A), the second insulating film 10234 in FIG. 87(B), the second insulating film 10304 in FIG. 87(A), and the second insulating film 10334 in FIG. 87(B) may be a thermal oxide film, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or the like. Alternatively, a laminated structure combining two or more of a thermal oxide film, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or the like may be used. Note that a silicon oxide film is preferable in the portion in contact with the semiconductor layer. This is because a silicon oxide film reduces the trap level at the interface with the semiconductor layer. Note that a silicon nitride film is preferable in the portion in contact with Mo.
This is because the silicon nitride film does not oxidize Mo.

The first semiconductor layer 10105 in FIG. 85, the first semiconductor layer 10205 in FIG.
The first semiconductor layer 10235 in FIG. 87B, the first semiconductor layer 10305 in FIG.
The first semiconductor layer 10335 of (B) is made of silicon or silicon germanium (Si
Ge) can be used.

The second semiconductor layer 10106 in FIG. 85, the second semiconductor layer 10206 in FIG.
The second semiconductor layer 10236 in FIG. 87B, the second semiconductor layer 10306 in FIG.
The second semiconductor layer 10336 of (B) can be made of silicon or the like containing phosphorus or the like.

85, the second conductive layer 10207 and the third conductive layer 10209 in FIG. 86A, the second conductive layer 10237 and the second conductive layer 10239 in FIG. 86B, the second conductive layer 10307 and the second conductive layer 10309 in FIG.
87(B), an indium tin oxide (ITO) film in which indium oxide is mixed with tin oxide, an indium tin silicon oxide (ITSO) film in which indium tin oxide (ITO) is mixed with silicon oxide, an indium zinc oxide (IZO) film in which indium oxide is mixed with zinc oxide, a zinc oxide film, a tin oxide film, or the like can be used. Note that IZO is a transparent conductive material formed by sputtering using a target in which ITO is mixed with 2 to 20 wt % zinc oxide (ZnO).

85, the second conductive layer 10207 and the third conductive layer 10209 in FIG. 86A, the second conductive layer 10237 and the second conductive layer 10239 in FIG. 86B, the second conductive layer 10307 and the second conductive layer 10309 in FIG.
87B, or the second conductive layer 10337, the second conductive layer 10339, and the fourth conductive layer 10343 may be made of a material having reflectivity such as Ti, Mo, Ta, Cr, or W.
Alternatively, a two-layer structure in which Ti, Mo, Ta, Cr, W and Al are laminated, or a three-layer structure in which Al is sandwiched between metals such as Ti, Mo, Ta, Cr, W, etc. may be used.

The third insulating film 10108 in FIG. 85, the third insulating film 10208 in FIG.
86(B), the third insulating film 10308 in FIG. 87(A), the third insulating film 10338 in FIG. 87(B), and the fourth insulating film 10
As 349, an inorganic material (silicon oxide, silicon nitride, silicon oxynitride, etc.) or a low dielectric constant organic compound material (photosensitive or non-photosensitive organic resin material) can be used. Alternatively, a material containing siloxane can be used. Note that siloxane is a material whose skeletal structure is formed by bonding silicon (Si) and oxygen (O). An organic group containing at least hydrogen (e.g., an alkyl group, an aromatic hydrocarbon) is used as a substituent. Alternatively, a fluoro group may be used as a substituent. Alternatively, an organic group containing at least hydrogen and a fluoro group may be used as a substituent.

The first alignment film 10110 in FIG. 85, the first alignment film 10210 in FIG. 86(A),
As the first alignment film 10240 in FIG. 86B, the first alignment film 10310 in FIG. 86B, and the first alignment film 10340 in FIG. 87B, a polymer film such as polyimide can be used.

Next, pixel structures in the case of combining each liquid crystal mode with a transistor will be described with reference to top views (layout diagrams) of pixels.

The liquid crystal mode includes TN (Twisted Nematic) mode, IPS (
In-Plane-Switching mode, FFS (Fringe Field)
Switching mode, MVA (Multi-domain Vertical)
Alignment mode, PVA (Patterned Vertical Ali
gnment), ASM (Axially Symmetric aligned Mi
cro-cell) mode, OCB (Optical Compensated Bi
effringence) mode, FLC (Ferroelectric Liquid)
Crystal) mode, AFLC (AntiFerroelectric Liqui)
d Crystal) can be used.

As the transistor, a thin film transistor (TFT) having a non-single crystal semiconductor layer typified by amorphous silicon, polycrystalline silicon, microcrystalline (also called microcrystal or semi-amorphous) silicon, or the like can be used.

Note that the structure of the transistor can be a top-gate type, a bottom-gate type, etc. As the bottom-gate type transistor, a channel-etch type, a channel-protective type, etc. can be used.

FIG. 88 is an example of a top view of a pixel in which the TN type and a transistor are combined.
By applying the pixel structure shown in FIG. 88 to a liquid crystal display device, the liquid crystal display device can be manufactured at low cost.

The pixel shown in FIG. 88 includes a scanning line 10401, a video signal line 10402, and a capacitance line 10403.
, a transistor 10404 , a pixel electrode 10405 , and a pixel capacitor 10406 .

The scanning line 10401 has a function of transmitting a signal (scanning signal) to the pixel.
The scanning line 104 has a function of transmitting a signal (video signal) to the pixel.
Since the scanning lines 10401 and the video signal lines 10402 are arranged in a matrix, they are formed of different conductive layers. Note that a semiconductor layer may be disposed at the intersections of the scanning lines 10401 and the video signal lines 10402. In this way, the scanning lines 10401 and the video signal lines 10402 are formed of different conductive layers.
402 and the cross capacitance can be reduced.

The capacitance line 10403 is disposed in parallel with the pixel electrode 10405. The portion where the capacitance line 10403 and the pixel electrode 10405 overlap becomes a pixel capacitance 10406. A part of the capacitance line 10403 extends along the video signal line 10402 so as to surround the video signal line 10402. This makes it possible to reduce crosstalk. Crosstalk is a phenomenon in which the potential of an electrode that is to hold a potential changes in accordance with a change in the potential of the video signal line 10402. The capacitance line 10403 and the video signal line 1040
By disposing a semiconductor layer between the first and second electrodes, the cross capacitance can be reduced.
The capacitance line 10403 is made of the same material as the scanning line 10401 .

The transistor 10404 functions as a switch that electrically connects the video signal line 10402 and the pixel electrode 10405. One of the source region and the drain region of the transistor 10404 is disposed so as to be surrounded by the other of the source region and the drain region of the transistor 10404. This increases the channel width of the transistor 10404, thereby improving the switching ability.
The gate electrode is disposed so as to surround the semiconductor layer.

The pixel electrode 10405 is electrically connected to one of the source electrode and the drain electrode of the transistor 10404. The pixel electrode 10405 is an electrode for applying a signal voltage transmitted by the video signal line 10402 to the liquid crystal element. The pixel electrode 10405 is rectangular. This makes it possible to increase the aperture ratio of the pixel.
A transparent material or a reflective material can be used as the pixel electrode 10405. Alternatively, a transparent material and a reflective material may be combined and used for the pixel electrode 10405.

89(A) is an example of a top view of a pixel in the case where the MVA method and a transistor are combined. By applying the pixel structure shown in FIG. 89(A) to a liquid crystal display device, a liquid crystal display device having a wide viewing angle, a fast response speed, and a high contrast can be obtained.

The pixel shown in FIG. 89A includes a scanning line 10501, a video signal line 10502, and a capacitance line 10
503, a transistor 10504, a pixel electrode 10505, and a pixel capacitance 10506,
and an alignment control protrusion 10507.

The scanning line 10501 has a function of transmitting a signal (scanning signal) to the pixel.
502 has a function of transmitting a signal (video signal) to the pixel.
Since the scanning lines 10501 and the video signal lines 10502 are arranged in a matrix, they are formed of different conductive layers. Note that a semiconductor layer may be disposed at the intersections of the scanning lines 10501 and the video signal lines 10502. In this way, the scanning lines 10501 and the video signal lines 10502 are formed of different conductive layers.
502 and the cross capacitance can be reduced.

The capacitance line 10503 is disposed in parallel with the pixel electrode 10505. The portion where the capacitance line 10503 and the pixel electrode 10505 overlap becomes a pixel capacitance 10506. A part of the capacitance line 10503 extends along the video signal line 10502 so as to surround the video signal line 10502. This makes it possible to reduce crosstalk. Crosstalk is a phenomenon in which the potential of an electrode that is to hold a potential changes in accordance with a change in the potential of the video signal line 10502. The capacitance line 10503 and the video signal line 1050
By disposing a semiconductor layer between the first and second electrodes, the cross capacitance can be reduced.
The capacitance line 10503 is made of the same material as the scanning line 10501 .

The transistor 10504 functions as a switch that electrically connects the video signal line 10502 and the pixel electrode 10505. One of the source region and the drain region of the transistor 10504 is disposed so as to be surrounded by the other of the source region and the drain region of the transistor 10504. This increases the channel width of the transistor 10504, thereby improving the switching ability.
The gate electrode is disposed so as to surround the semiconductor layer.

The pixel electrode 10505 is electrically connected to one of the source electrode and the drain electrode of the transistor 10504. The pixel electrode 10505 is an electrode for applying a signal voltage transmitted by the video signal line 10502 to the liquid crystal element. The pixel electrode 10505 is rectangular. This makes it possible to increase the aperture ratio of the pixel.
A transparent material or a reflective material can be used as the pixel electrode 10505. Alternatively, a transparent material and a reflective material may be combined and used for the pixel electrode 10505.

The alignment control protrusion 10507 is formed on the opposing substrate. The alignment control protrusion 10507 has a function of radially aligning the liquid crystal molecules. There is no limitation on the shape of the alignment control protrusion 10507. For example, the alignment control protrusion 10507 may be shaped like a dogleg. This makes it possible to form a plurality of regions in which the alignment of the liquid crystal molecules is different. This makes it possible to improve the viewing angle.

89(B) is an example of a top view of a pixel in the case where a PVA method and a transistor are combined. By applying the pixel structure shown in FIG. 89(B) to a liquid crystal display device, a liquid crystal display device with a wide viewing angle, a fast response speed, and a high contrast can be obtained.

The pixel shown in FIG. 89B includes a scanning line 10511, a video signal line 10512, and a capacitance line 10513.
513, a transistor 10514, a pixel electrode 10515, and a pixel capacitance 10516,
It has an electrode cutout portion 10517.

The scanning line 10511 has a function of transmitting a signal (scanning signal) to the pixel.
The scanning line 105 has a function of transmitting a signal (video signal) to the pixel.
Since the scanning lines 10511 and the video signal lines 10512 are arranged in a matrix, they are formed of different conductive layers. Note that a semiconductor layer may be disposed at the intersections of the scanning lines 10511 and the video signal lines 10512. In this way, the scanning lines 10511 and the video signal lines 10512 may be formed of different conductive layers.
512 and the cross capacitance can be reduced.

The capacitance line 10513 is disposed in parallel with the pixel electrode 10515. The portion where the capacitance line 10513 and the pixel electrode 10515 overlap becomes a pixel capacitance 10516. A part of the capacitance line 10513 extends along the video signal line 10512 so as to surround the video signal line 10512. This makes it possible to reduce crosstalk. Crosstalk is a phenomenon in which the potential of an electrode that is to hold a potential changes in accordance with a change in the potential of the video signal line 10512. The capacitance line 10513 and the video signal line 10516 overlap each other.
By disposing a semiconductor layer between the first and second electrodes, the cross capacitance can be reduced.
The capacitance line 10513 is made of the same material as the scanning line 10511 .

The transistor 10514 functions as a switch that electrically connects the video signal line 10512 and the pixel electrode 10515. One of the source region and the drain region of the transistor 10514 is disposed so as to be surrounded by the other of the source region and the drain region of the transistor 10514. This increases the channel width of the transistor 10514, thereby improving the switching ability.
The gate electrode is disposed so as to surround the semiconductor layer.

The pixel electrode 10515 is electrically connected to one of the source electrode and the drain electrode of the transistor 10514. The pixel electrode 10515 is an electrode for applying a signal voltage transmitted by the video signal line 10512 to the liquid crystal element. The pixel electrode 10515 has a shape that matches the shape of the electrode cutout portion 10517. Specifically,
The pixel electrode 10515 has a shape in which a notched portion is formed in a portion where there is no liquid crystal. This makes it possible to form a plurality of regions in which the orientation of liquid crystal molecules is different. The viewing angle can be improved. Note that the pixel electrode 10515 can be made of a transparent material or a reflective material. Alternatively, a combination of a transparent material and a reflective material can be used for the pixel electrode 10515.

90A is an example of a top view of a pixel in the case where an IPS system and a transistor are combined. By applying the pixel structure shown in FIG. 90A to a liquid crystal display device, a liquid crystal display device having a wide viewing angle and a small grayscale dependency of a response speed can be obtained in principle.

The pixel shown in FIG. 90A includes a scanning line 10601, a video signal line 10602, and a common electrode 10603.
10603, a transistor 10604, and a pixel electrode 10605.

The scanning line 10601 has a function of transmitting a signal (scanning signal) to the pixel.
602 has a function of transmitting a signal (video signal) to the pixel.
The scanning lines 10601 and the video signal lines 10602 are arranged in a matrix, and therefore are formed of different conductive layers. A semiconductor layer may be disposed at the intersections of the scanning lines 10601 and the video signal lines 10602.
The cross capacitance with the pixel electrode 10602 can be reduced.
It is formed to match the shape of 605.

The common electrode 10603 is disposed in parallel with the pixel electrode 10605.
Reference numeral 10603 denotes an electrode for generating a horizontal electric field. The common electrode 10603 has a bent comb-like shape. A part of the common electrode 10603 extends along the video signal line 10602 so as to surround the video signal line 10602. This makes it possible to reduce crosstalk. Crosstalk is a phenomenon in which the potential of an electrode that should hold a potential changes in accordance with a change in the potential of the video signal line 10602. By arranging a semiconductor layer between the common electrode 10603 and the video signal line 10602, it is possible to reduce the cross capacitance. The part of the common electrode 10603 that is arranged in parallel with the scanning line 10601 is made of the same material as the scanning line 10601. The common electrode 106
The portion disposed in parallel to the pixel electrode 10605 of 03 is made of the same material as the pixel electrode 10605 .

The transistor 10604 functions as a switch that electrically connects the video signal line 10602 and the pixel electrode 10605. One of the source region and the drain region of the transistor 10604 is disposed so as to be surrounded by the other of the source region and the drain region of the transistor 10604. This increases the channel width of the transistor 10604, thereby improving the switching ability.
The gate electrode is disposed so as to surround the semiconductor layer.

The pixel electrode 10605 is electrically connected to one of the source electrode and the drain electrode of the transistor 10604. The pixel electrode 10605 is an electrode for applying a signal voltage transmitted by the video signal line 10602 to the liquid crystal element. The pixel electrode 10605 has a bent comb-like shape. This allows a lateral electric field to be applied to the liquid crystal molecules.
A plurality of regions in which the liquid crystal molecules are aligned differently can be formed. The viewing angle can be improved. Note that the pixel electrode 10605 can be made of a transparent material or a reflective material. Alternatively, the pixel electrode 10605 can be made of a combination of a transparent material and a reflective material.

The comb-shaped portion of the common electrode 10603 and the pixel electrode 10605 may be formed of different conductive layers.
The pixel electrode 10605 may be formed of the same conductive layer as the scanning line 10601 or the video signal line 10602. Similarly, the pixel electrode 10605 may be formed of the same conductive layer as the scanning line 10601 or the video signal line 10602.

90B is a top view of a pixel in the case where the FFS method and a transistor are combined. By applying the pixel structure shown in FIG. 90B to a liquid crystal display device, a liquid crystal display device having a wide viewing angle and a small grayscale dependency of the response speed can be obtained in principle.

The pixel shown in FIG. 90B includes a scanning line 10611, a video signal line 10612, and a common electrode 10613.
10613, a transistor 10614, and a pixel electrode 10615.

The scanning line 10611 has a function of transmitting a signal (scanning signal) to the pixel.
The scanning line 106 has a function of transmitting a signal (video signal) to the pixel.
Since the scanning lines 10611 and the video signal lines 10612 are arranged in a matrix, they are formed of different conductive layers. Note that a semiconductor layer may be disposed at the intersections of the scanning lines 10611 and the video signal lines 10612. In this way, the scanning lines 10611 and the video signal lines 10612 may be formed of different conductive layers.
The cross capacitance between the pixel electrode 10612 and the image signal line 10612 can be reduced.
It is formed to fit the shape of 0615.

The common electrode 106013 is uniformly formed under the pixel electrode 10615 and under the area between the pixel electrodes 10615 and 10615. Note that a transparent material or a reflective material can be used as the common electrode 106013. Alternatively, a combination of a transparent material and a reflective material may be used for the common electrode 106013.

The transistor 10614 functions as a switch that electrically connects the video signal line 10612 and the pixel electrode 10615. One of the source region and the drain region of the transistor 10604 is disposed so as to be surrounded by the other of the source region and the drain region of the transistor 10614. This increases the channel width of the transistor 10614, thereby improving the switching ability.
The gate electrode is disposed so as to surround the semiconductor layer.

The pixel electrode 10615 is electrically connected to one of the source electrode and the drain electrode of the transistor 10614. The pixel electrode 10615 is an electrode for applying a signal voltage transmitted by the video signal line 10612 to the liquid crystal element. The pixel electrode 10615 has a bent comb-like shape. This allows a lateral electric field to be applied to the liquid crystal molecules.
The comb-tooth shaped pixel electrode 10615 is disposed closer to the liquid crystal layer than the uniform portion of the common electrode 10613. A plurality of regions in which the liquid crystal molecules are aligned differently can be formed.
The viewing angle can be improved. Note that a transparent material or a reflective material can be used for the pixel electrode 10615. Alternatively, a transparent material and a reflective material may be combined for use in the pixel electrode 10615.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 11)
In this embodiment mode, a manufacturing process of a liquid crystal cell (also called a liquid crystal panel) will be described.

The manufacturing process of a liquid crystal cell when the vacuum injection method is used as the liquid crystal filling method is shown in FIG.
This will be described with reference to Figures 92(A) to (C).

FIG. 92C is a cross-sectional view showing a liquid crystal cell.
107 is attached via a spacer 70106 and a sealant 70105 .
A liquid crystal 70109 is disposed between the first substrate 70101 and the second substrate 70107. Note that an alignment film 70102 is formed on the first substrate 70101, and the alignment film 701
08 is formed on a second substrate 70107.

A plurality of pixels are formed in a matrix on the first substrate 70101. Each of the plurality of pixels may have a transistor.
It may be called an FT substrate, an array substrate, or a TFT array substrate. As the first substrate 70101, a single crystal substrate, an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a paper substrate, a cellophane substrate, a stone substrate, a wood substrate, a cloth substrate (including natural fibers (silk, cotton, hemp), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate, cupra, rayon, regenerated polyester), etc.), a leather substrate, a rubber substrate, a stainless steel substrate, a substrate having stainless steel foil, etc. may be used. Alternatively, the skin (skin surface, dermis) or subcutaneous tissue of an animal such as a human may be used as the substrate. However, it is not limited to this, and various substrates may be used.

A common electrode, a color filter, a black matrix, and the like are formed on the second substrate 70107. Note that the second substrate 70107 may also be called an opposing substrate or a color filter substrate.

The alignment film 70102 has a function of aligning liquid crystal molecules in a certain direction.
The alignment film 70108 may be a polyimide resin or the like. However, the alignment film 70108 is not limited to this, and various materials may be used. Note that the alignment film 70108 is similar to the alignment film 70102.

The sealant 70105 is used to seal the first substrate 70101 and the second substrate 70102 so as to prevent the liquid crystal 70109 from leaking.
70107. That is, it functions as a sealant.

The spacer 70106 has a function of keeping the space (liquid crystal cell gap) between the first substrate 70101 and the second substrate 70107 constant. As the spacer 70106, a granular spacer or a columnar spacer can be used. The granular spacer can be either fiber-shaped or spherical. The material of the granular spacer can be plastic or glass. Note that spherical spacers made of plastic are called plastic beads and are widely used. Note that fiber-shaped spacers made of glass are called glass fibers and are used by being mixed into a sealing material.

91A is a cross-sectional view showing a process of forming an alignment film 70102 on a first substrate 70101. The alignment film 70102 is formed on the first substrate 70101 by a roller coating method using a roller 70103. However, the alignment film 701
As a method for forming the alignment film 70102, in addition to the roller coating method, an offset printing method, a dip coating method, an air knife coating method, a curtain coating method, a wire bar coating method, a gravure coating method, an extrusion coating method, etc. can be used. Then, the alignment film 70102 is subjected to a preliminary baking and a main baking in this order.

91(B) is a cross-sectional view showing the process of performing a rubbing treatment on the alignment film 70102. The rubbing treatment is performed by rotating a rubbing roller 70104, which is a drum wrapped with cloth, to rub the alignment film 70102. When this rubbing treatment is performed on the alignment film 70102, grooves for aligning the liquid crystal molecules in a certain direction are formed in the alignment film 70102. However, this is not limited to this, and grooves may be formed in the alignment film using an ion beam. Thereafter,
A water cleaning process is performed on the first substrate 70101.
It is possible to remove foreign matter or dirt from the surface.

Although not shown, an alignment film 70108 is formed on the second substrate 70107 in the same manner as the first substrate 70101, and a rubbing treatment is performed on the alignment film 70108. However, the present invention is not limited to this, and grooves may be formed in the alignment film using an ion beam.

91C is a cross-sectional view showing a process of forming a seal material 70105 on an alignment film 70102. The seal material 70105 is applied by a drawing device or screen printing, and a seal pattern is formed. This seal pattern is formed along the outer periphery of the first substrate 70101, and a liquid crystal injection port is provided in a part of the seal pattern.
V resin is spot-coated on the outside of the display area of the first substrate 70101 using a dispenser or the like.

Note that the sealing material 70105 may be formed on the second substrate 70107.

91(D) is a cross-sectional view showing a step of dispersing the spacers 70106 on the first substrate 70101. The spacers 70106 are sprayed from a nozzle together with compressed gas (dry spraying). Alternatively, the spacers 70106 are mixed with a volatile liquid and sprayed by spraying the liquid through a nozzle (wet spraying). By such dry or wet spraying, the spacers 70106 can be uniformly sprayed on the first substrate 70101.

Here, a case where a spherical granular spacer is used as the spacer 70106 has been described. However, this is not limiting, and a columnar spacer can also be used. The columnar spacer may be formed on the first substrate 70101 or the second substrate 70107. Alternatively, a part of the spacer may be formed on the first substrate 70101, and the rest may be formed on the second substrate 70107.

Spacers may be mixed into the sealing material, which makes it easier to maintain a constant cell gap for the liquid crystal.

91E is a cross-sectional view showing a step of bonding the first substrate 70101 and the second substrate 70107 together. The first substrate 70101 and the second substrate 70107 are bonded together in the atmosphere. Then, the first substrate 70101 and the second substrate 70107 are pressed together so that the gap between them is constant. After that, ultraviolet irradiation or heat treatment is performed to bond the sealant 701 to the second substrate 70107.
05, the sealing material 70105 hardens.

92A and 92B are top views showing the process of filling the liquid crystal.
A cell (also called an empty cell) in which the first substrate 101 and the second substrate 70107 are bonded together is placed in a vacuum chamber. After that, the pressure inside the vacuum chamber is reduced, and the liquid crystal injection port 70113 of the empty cell is immersed in liquid crystal. Then, when the vacuum chamber is opened to the atmosphere, liquid crystal 70109 is filled into the empty cell by differential pressure and capillary action.

When the required amount of liquid crystal 70109 is filled into the empty cell, the liquid crystal injection port is sealed with resin 70110. Then, excess liquid crystal adhering to the empty cell is washed away. After that, the liquid crystal 70109 is subjected to a realignment process by an annealing process. In this way, the liquid crystal cell is completed.

Next, the manufacturing process of a liquid crystal cell when the dropping method is used as the liquid crystal filling method is shown in FIG.
This will be described with reference to (A) to (D) and Figures 94 (A) to (C).

FIG. 94C is a cross-sectional view showing a liquid crystal cell.
307 is attached via a spacer 70306 and a sealant 70305 .
A liquid crystal 70309 is disposed between the first substrate 70301 and the second substrate 70307. Note that an alignment film 70302 is formed on the first substrate 70301, and an alignment film 703
08 is formed on a second substrate 70307.

A plurality of pixels are formed in a matrix on the first substrate 70301. Each of the plurality of pixels may have a transistor.
It may be called an FT substrate, an array substrate, or a TFT array substrate. As the first substrate 70301, a single crystal substrate, an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a paper substrate, a cellophane substrate, a stone substrate, a wood substrate, a cloth substrate (including natural fibers (silk, cotton, hemp), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate, cupra, rayon, regenerated polyester), etc.), a leather substrate, a rubber substrate, a stainless steel substrate, a substrate having stainless steel foil, etc. may be used. Alternatively, the skin (skin surface, dermis) or subcutaneous tissue of an animal such as a human may be used as the substrate. However, it is not limited to this, and various substrates may be used.

A common electrode, a color filter, a black matrix, and the like are formed on the second substrate 70307. Note that the second substrate 70307 may also be called an opposing substrate or a color filter substrate.

The alignment film 70302 has a function of aligning liquid crystal molecules in a certain direction.
The alignment film 70308 may be a polyimide resin or the like. However, the alignment film 70308 is not limited to this, and various materials may be used. Note that the alignment film 70308 is similar to the alignment film 70302.

The sealant 70305 is disposed between the first substrate 70301 and the second substrate 70302 so as to prevent leakage of the liquid crystal 70309.
That is, it functions as a sealant.

The spacer 70306 has a function of keeping the space (liquid crystal cell gap) between the first substrate 70301 and the second substrate 70307 constant. As the spacer 70306, a granular spacer or a columnar spacer can be used. The granular spacer can be either fiber-shaped or spherical. The material of the granular spacer can be plastic or glass. Note that spherical spacers made of plastic are called plastic beads and are widely used. Note that fiber-shaped spacers made of glass are called glass fibers and are used by being mixed into a sealing material.

93A is a cross-sectional view showing a process of forming an alignment film 70302 on a first substrate 70301. The alignment film 70302 is formed on the first substrate 70301 by a roller coating method using a roller 70303. However, the alignment film 703
As a method for forming the alignment film 70302, in addition to the roller coating method, offset printing, dip coating, air knife coating, curtain coating, wire bar coating, gravure coating, extrusion coating, etc. can also be used. Thereafter, the alignment film 70302 is subjected to preliminary baking and main baking in this order.

Fig. 93(B) is a cross-sectional view showing the process of performing a rubbing treatment on the alignment film 70302. The rubbing treatment is performed by rotating a rubbing roller 70304, which is a drum wrapped with cloth, to rub the alignment film 70302. When this rubbing treatment is performed on the alignment film 70302, grooves for aligning the liquid crystal molecules in a certain direction are formed in the alignment film 70302. However, this is not limited to this, and grooves may be formed in the alignment film using an ion beam. Thereafter,
A water cleaning process is performed on the first substrate 70301.
It is possible to remove foreign matter or dirt from the surface.

Although not shown, an alignment film 70308 is formed on the second substrate 70307 in the same manner as the first substrate 70301, and a rubbing treatment is performed on the alignment film 70308. However, the present invention is not limited to this, and grooves may be formed in the alignment film using an ion beam.

93C is a cross-sectional view showing a process of forming a sealant 70305 on the alignment film 70302. The sealant 70305 is applied by a drawing device or screen printing, and a seal pattern is formed. This seal pattern is formed along the outer periphery of the first substrate 70301. Here, the sealant 70305 is a radical type UV resin or a cationic type UV resin.
V resin is used. Then, conductive resin is spot-applied using a dispenser.

Note that the sealing material 70305 may be formed on the second substrate 70307.

93(D) is a cross-sectional view showing a step of dispersing the spacers 70306 on the first substrate 70301. The spacers 70306 are sprayed from a nozzle together with compressed gas (dry spraying). Alternatively, the spacers 70306 are mixed with a volatile liquid and sprayed by spraying the liquid through a nozzle (wet spraying). By such dry or wet spraying, the spacers 70306 can be uniformly sprayed on the first substrate 70301.

Here, a case where a spherical granular spacer is used as the spacer 70306 has been described. However, this is not limiting, and a columnar spacer can also be used. The columnar spacer may be formed on the first substrate 70301 or the second substrate 70307. Alternatively, a part of the spacer may be formed on the first substrate 70301, and the rest may be formed on the second substrate 70307.

Spacers may be mixed into the sealing material, which makes it easier to maintain a constant cell gap for the liquid crystal.

94A is a cross-sectional view showing a step of dropping a liquid crystal 70309. After a degassing process is performed on the liquid crystal 70309, the liquid crystal 70309 is dropped on the inside of the sealant 70305.

94B is a top view after the liquid crystal 70309 is dropped.
Since the second insulating film 70309 is formed along the outer periphery of the first substrate 70301, the liquid crystal 70309 does not leak.

FIG. 94C is a cross-sectional view showing the step of bonding the first substrate 70301 and the second substrate 70307 together. The first substrate 70301 and the second substrate 70307 are bonded together in a vacuum chamber. Then, both substrates are pressurized so that the gap between the first substrate 70301 and the second substrate 70307 is constant. After that, the sealant 70305 is irradiated with ultraviolet light, thereby hardening the sealant 70305. Here, it is preferable to cover the display portion with a mask and irradiate the sealant 70305 with ultraviolet light. This is because the liquid crystal 70309 can be prevented from being deteriorated by ultraviolet light. Then, an annealing process is performed to harden the sealant 70305.
A realignment process is performed on the liquid crystal 70309. In this way, the liquid crystal cell is completed.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 12)
In this embodiment mode, a configuration and an operation of a pixel of a display device will be described.

95(A) and (B) are timing charts showing an example of digital time gray scale driving. The timing chart in Fig. 95(A) shows a driving method in which a signal writing period (address period) to a pixel and a light emission period (sustain period) are separated.

The period required to completely display an image for one display area is called one frame period. One frame period has multiple subframe periods, and one subframe period has an address period and a sustain period. The address periods Ta1 to Ta4 indicate the time required to write signals to pixels in all rows, and the periods Tb1 to Tb4 indicate the time required to write signals to pixels in one row (or one pixel). The sustain periods Ts1 to Ts4 indicate the time for which the pixels are maintained in a lit or unlit state according to the video signals written to them, and the ratio of their lengths is called Ts
1:Ts2:Ts3:Ts4= ²³ :22: ²¹ : ²⁰ =8: ⁴ :2:1. The gradation is expressed depending on which sustain period is lighted.

The operation will be described. First, in the address period Ta1, pixel selection signals are input to the scanning lines in order from the first row, and pixels are selected. Then, when a pixel is selected, a video signal is input to the pixel from the signal line. Then, when a video signal is written to a pixel, the pixel holds the signal until a signal is input again. The written video signal controls the lighting and non-lighting of each pixel in the sustain period Ts1. Similarly, video signals are input to the pixels in the address periods Ta2, Ta3, and Ta4, and the video signals control the lighting and non-lighting of each pixel in the sustain periods Ts2, Ts3, and Ts4. Then, in each subframe period, the pixels are not lit during the address period, and after the address period ends, the sustain period begins, and the pixels to which a signal for lighting is written are lit.

Here, with reference to FIG. 95B, a description will be given focusing on the i-th pixel row. First, in an address period Ta1, pixel selection signals are input to the scanning lines in order starting from the first row.
During period Tb1(i) of a1, the pixels in the i-th row are selected. When the pixels in the i-th row are selected, a video signal is input from the signal line to the pixels in the i-th row.
When a video signal is written to the pixels in the i-th row, the pixels in the i-th row hold the signal until a signal is input again. The written video signal controls whether the pixels in the i-th row are turned on or off during the sustain period Ts1. Similarly, during the address periods Ta2, Ta3, and Ts4,
At a4, a video signal is input to the pixels in the i-th row, and the video signal controls whether the pixels in the i-th row are turned on or off during the sustain periods Ts2, Ts3, and Ts4. In each subframe period, the pixels are not turned on during the address period, and after the address period ends, the sustain period begins, and the pixels to which a signal to turn on the pixels is written are turned on.

Although the case of expressing 4-bit gradation has been described here, the number of bits and the number of gradations are not limited to this. The order of lighting does not have to be Ts1, Ts2, Ts3, and Ts4, but may be random, or may be divided into a plurality of parts for light emission.
The lighting times Ts3, Ts4 do not need to be powers of two, and may be the same length or may be slightly shifted from a power of two.

Next, a driving method in the case where the signal writing period (address period) to the pixels and the light emission period (sustain period) are not separated will be described. In other words, the pixels in a row in which the video signal writing operation has been completed retain the signal until the next signal writing (or erasing) to the pixel. The period from the writing operation to the next signal writing to the pixel is called the data retention time. During this data retention time, the pixel is turned on or off according to the video signal written to the pixel. The same operation is performed up to the last row, and the address period ends. Then, the signal writing operation for the next sub-frame period is started in order from the row in which the data retention time has ended.

In this way, in the case of a driving method in which the pixel is turned on or off according to the video signal written to the pixel immediately after the signal writing operation is completed and the data holding time is reached, even if it is attempted to make the data holding time shorter than the address period, signals cannot be input to two rows at the same time, so the address periods must not overlap, and therefore the data holding time cannot be shortened, which results in difficulty in performing high gradation display.

Therefore, by providing an erase period, a data holding time shorter than the address period is set. A driving method in which an erase period is provided to set a data holding time shorter than the address period will be described with reference to FIG.

First, in an address period Ta1, pixel scanning signals are input to the scanning lines starting from the first row.
A pixel is selected. When the pixel is selected, a video signal is input from a signal line to the pixel. When a video signal is written to the pixel, the pixel holds the signal until a signal is input again. A sustain period Ts1 is generated by the written video signal.
The lighting or non-lighting of each pixel in the row is controlled. In the row where the writing operation of the video signal is completed, the pixel is turned on or off according to the video signal written immediately. The same operation is performed up to the last row, and the address period Ta1 is ended. Then, the signal writing operation of the next subframe period is started in order from the row where the data holding time is ended. Similarly, video signals are input to the pixels in the address periods Ta2, Ta3, and Ta4, and the lighting or non-lighting of each pixel in the sustain periods Ts2, Ts3, and Ts4 is controlled by the video signals. The end of the sustain period TS4 is set by the start of the erase operation. This is because when the signal written to the pixel in the erase time Te of each row is erased, the pixel is forced to be non-lighted until the signal is written to the next pixel, regardless of the video signal written to the pixel in the address period. In other words, the data holding time ends from the pixel in the row where the erase time Te started.

Here, with reference to FIG. 96(B), a description will be given focusing on the i-th row of pixels. In the i-th row of pixels, pixel scanning signals are input to the scanning lines in order from the first row during the address period Ta1, and the pixels are selected. Then, when the i-th row pixels are selected during period Tb1(i), a video signal is input to the i-th row pixels. Then, when a video signal is written to the i-th row pixels, the i-th row pixels retain that signal until a signal is input again. This written video signal controls whether the i-th row pixels are turned on or off during the sustain period Ts1(i). In other words, when the writing operation of the video signal to the i-th row is completed,
The pixels in the i-th row are turned on or off according to the video signal that is immediately written. Similarly, a video signal is input to the pixels in the i-th row in the address periods Ta2, Ta3, and Ta4, and the pixels in the i-th row are controlled to be turned on or off in the sustain periods Ts2, Ts3, and Ts4 by the video signal. The end of the sustain period Ts4(i) is set by the start of the erase operation, because the pixels in the i-th row are forcibly turned off regardless of the video signal written to the pixels in the i-th row during the erase time Ts(i) of the i-th row. In other words, when the erase time Te(i) starts, the data retention time of the pixels in the i-th row ends.

Therefore, it is possible to provide a display device with a high gray scale and a high duty ratio (the ratio of the lighting period to one frame period) that is shorter than the address period without separating the address period and the sustain period. Since it is possible to reduce the instantaneous luminance, it is possible to improve the reliability of the display element.

Although the case of expressing 4-bit gradation has been described here, the number of bits and the number of gradations are not limited to this. Also, the lighting order does not have to be Ts1, Ts2, Ts3, and Ts4, but may be random, or may be divided into a plurality of parts.
The lighting times Ts3 and Ts4 do not have to be a power of two, and may be the same length, or may be slightly shifted from a power of two.

This section explains the configuration and operation of pixels to which digital time grayscale driving can be applied.

Figure 97 shows an example of a pixel configuration to which digital time grayscale driving can be applied.

The pixel 80300 includes a switching transistor 80301 and a driving transistor 803
80302, a light-emitting element 80304, and a capacitor 80303. The switching transistor 80301 has a gate connected to a scan line 80306, a first electrode (one of a source electrode and a drain electrode) connected to a signal line 80305, and a second electrode (the other of the source electrode and the drain electrode) connected to the gate of the driving transistor 80302. The driving transistor 80302 has a gate connected to a power supply line 80307 via the capacitor 80303, a first electrode connected to the power supply line 80307, and a second electrode connected to the first electrode (
The second electrode of the light emitting element 80304 corresponds to a common electrode 80308.

A low power supply potential is set to the second electrode (common electrode 80308) of the light emitting element 80304. The low power supply potential is a potential that satisfies the condition that the low power supply potential is smaller than the high power supply potential based on the high power supply potential set to the power supply line 80307, and the low power supply potential may be set to, for example, GND or 0 V. The potential difference between the high power supply potential and the low power supply potential is set to the light emitting element 8030.
4 to pass a current through the light emitting element 80304 to cause the light emitting element 80304 to emit light, the high power supply potential and the low power supply potential are set so that the potential difference between them is equal to or greater than the forward threshold voltage of the light emitting element 80304.

Note that the capacitor 80303 can be omitted by substituting the gate capacitance of the driving transistor 80302. Regarding the gate capacitance of the driving transistor 80302, a capacitance may be formed in a region where the source region, the drain region, or the LDD region overlaps with the gate electrode, or a capacitance may be formed between the channel region and the gate electrode.

When a pixel is selected by the scanning line 80306, that is, when the switching transistor 80
When 301 is turned on, a video signal is input to the pixel from signal line 80305.
Then, a charge of a voltage equivalent to the video signal is stored in the capacitor 80303, and the capacitor 80303 holds the voltage. This voltage is a voltage between the gate and the first electrode of the driving transistor 80302, and corresponds to a gate-source voltage Vgs of the driving transistor 80302.

In general, the operating region of a transistor can be divided into a linear region and a saturation region. The boundary between them occurs when (Vgs-Vth)=Vds, where Vds is the drain-source voltage, Vgs is the gate-source voltage, and Vth is the threshold voltage. (Vgs-Vth)>Vds
In the case of , it is in the linear region, and the current value is determined by the magnitude of Vds and Vgs.
When Vgs-Vth) < Vds, the region is saturated. Ideally, even if Vds changes,
The current value remains almost unchanged. In other words, the current value is determined only by the magnitude of Vgs.

In the case of a voltage input voltage driving method, a video signal is input to the gate of the driving transistor 80302 such that the driving transistor 80302 is in two states, that is, fully on or off. In other words, the driving transistor 80302 is operated in a linear region.

Therefore, when the video signal is such that the driving transistor 80302 is turned on, ideally the power supply potential VDD set in the power supply line 80307 is set as it is to the first electrode of the light emitting element 80304 .

In other words, ideally, the voltage applied to the light emitting element 80304 is kept constant.
Then, a plurality of subframe periods are provided within one frame period, a video signal is written to a pixel in each subframe period, and the pixels are controlled to be turned on or off in each subframe period. The total of the turned-on subframe periods is used to obtain the luminance:
Expresses gradation.

Note that, by inputting a video signal that causes the driving transistor 80302 to operate in a saturation region, a current can be passed through the light emitting element 80304. If the light emitting element 80304 is an element that determines its luminance according to a current, a decrease in luminance due to deterioration of the light emitting element 80304 can be suppressed. Furthermore, by making the video signal analog, the light emitting element 8030
A current corresponding to a video signal can be passed through the pixel 4. In this case, analog gradation driving can be performed.

Figure 98 shows an example of a pixel configuration to which digital time grayscale driving can be applied.

The pixel 80400 includes a switching transistor 80401 and a driving transistor 804
02, a capacitor element 80403, a light-emitting element 80404, and a rectifying element 80409.
The switching transistor 80401 has a gate connected to a second scanning line 80406.
A first electrode (one of a source electrode and a drain electrode) is connected to a signal line 80405, and a second electrode (the other of the source electrode and the drain electrode) is connected to the gate of a driving transistor 80402. The driving transistor 80402 has a gate connected to a power supply line 80407 via a capacitor element 80403, and a gate connected to a second scanning line 80404 via a rectifying element 80309.
10, a first electrode is connected to a power supply line 80407, and a second electrode is connected to a light emitting element 8040
The second electrode of the light-emitting element 80404 corresponds to a common electrode 80408.

A low power supply potential is set to the second electrode (common electrode 80408) of the light emitting element 80404. The low power supply potential is a potential that satisfies the condition that the low power supply potential is smaller than the high power supply potential based on the high power supply potential set to the power supply line 80407, and the low power supply potential may be set to, for example, GND or 0 V. The potential difference between the high power supply potential and the low power supply potential is set to the light emitting element 8040.
4 to pass a current through the light emitting element 80404 to cause the light emitting element 80404 to emit light, the high power supply potential and the low power supply potential are set so that the potential difference between them is equal to or greater than the forward threshold voltage of the light emitting element 80404.

Note that the capacitor 80403 can be omitted by substituting the gate capacitance of the driving transistor 80402. Regarding the gate capacitance of the driving transistor 80402, a capacitance may be formed in a region where the source region, the drain region, or the LDD region overlaps with the gate electrode, or a capacitance may be formed between the channel region and the gate electrode.

Note that a diode-connected transistor can be used as the rectifying element 80409. In addition to the diode-connected transistor, a PN junction diode, a PIN junction diode, a Schottky diode, a diode formed of a carbon nanotube, or the like may be used. The polarity of the diode-connected transistor may be either an N-channel type or a P-channel type.

The pixel 80400 is the pixel shown in FIG. 97, except that a rectifying element 80409 and a second scanning line 8041 are added.
0 is added. Therefore, the switching transistor 80401 shown in FIG.
, a driving transistor 80402, a capacitor element 80403, a light emitting element 80404, a signal line 8
97. The first scanning line 80405, the first scanning line 80406, the power supply line 80407 and the common electrode 80408 correspond to the switching transistor 80301 and the driving transistor 803 shown in FIG.
02, a capacitor element 80303, a light-emitting element 80304, a signal line 80305, and a scanning line 80306
, the power supply line 80307 and the common electrode 80308. Therefore, the writing operation and light emitting operation in Fig. 98 are similar to the writing operation and light emitting operation described in Fig. 97, and therefore the description thereof will be omitted.

An erase operation will now be described. During the erase operation, an H-level signal is input to the second scan line 80410. Then, a current flows through the rectifying element 80409, and the gate potential of the driving transistor 80402 held by the capacitor element 80403 can be set to a certain potential. In other words, the gate potential of the driving transistor 80402 is set to a certain potential, and the driving transistor 80402 can be forcibly turned off regardless of the video signal written to the pixel.

It is to be noted that the L-level signal input to the second scanning line 80410 is set to a potential such that no current flows through the rectifying element 80409 when a video signal for turning off a pixel is written to the pixel.
The H-level signal input to the second scanning line 80410 is set to a potential that can set the gate of the driving transistor 80402 to a potential that turns off the driving transistor 80402, regardless of the video signal written in the pixel.

Note that a diode-connected transistor can be used as the rectifying element 80409. In addition to the diode-connected transistor, a PN junction diode,
It is also possible to use an IN junction diode, a Schottky diode, a diode formed of a carbon nanotube, etc. The polarity of the diode-connected transistor may be either an N-channel type or a P-channel type.

Figure 99 shows an example of a pixel configuration to which digital time grayscale driving can be applied.

The pixel 80500 includes a switching transistor 80501 and a driving transistor 805
80502, a capacitor element 80503, a light-emitting element 80504, and an erasing transistor 80509. The switching transistor 80501 has a gate connected to a second scan line 80506, a first electrode (one of a source electrode and a drain electrode) connected to a signal line 80505, and a second electrode (the other of the source electrode and the drain electrode) connected to the gate of a driving transistor 80502. The driving transistor 80502 has a gate connected to the capacitor element 8050
3, and the gate of the first erasing transistor 80509 is connected to the power supply line 80507.
The first electrode is connected to a power supply line 80507, and the second electrode is connected to a light emitting element 8050
The gate of the erasing transistor is connected to the second scanning line 80510, and the second electrode of the erasing transistor is connected to the power supply line 80507.
The second electrode of 0504 corresponds to the common electrode 80508 .

A low power supply potential is set to the second electrode (common electrode 80508) of the light emitting element 80504. The low power supply potential is a potential that satisfies the condition that the low power supply potential is smaller than the high power supply potential based on the high power supply potential set to the power supply line 80507, and the low power supply potential may be set to, for example, GND or 0 V. The potential difference between the high power supply potential and the low power supply potential is set to the light emitting element 8050.
4 to pass a current through the light emitting element 80504 to cause the light emitting element 80504 to emit light, the high power supply potential and the low power supply potential are set so that the potential difference between them is equal to or greater than the forward threshold voltage of the light emitting element 80504.

Note that the capacitor 80503 can be omitted by substituting the gate capacitance of the driving transistor 80502. Regarding the gate capacitance of the driving transistor 80502, a capacitance may be formed in a region where the source region, the drain region, or the LDD region overlaps with the gate electrode, or a capacitance may be formed between the channel region and the gate electrode.

The pixel 80500 is obtained by adding an erasing transistor 80509 and a second scanning line 80510 to the pixel shown in FIG. 97. Therefore, the switching transistor 80501, the driving transistor 80502, the capacitor element 80503, and the light-emitting element 80504 shown in FIG.
, a signal line 80505, a first scanning line 80506, a power supply line 80507, and a common electrode 8050
8 correspond to the switching transistor 80301, the driving transistor 80302, the capacitor element 80303, the light emitting element 80304, the signal line 80305, the scanning line 80306, the power supply line 80307, and the common electrode 80308 shown in FIG.
The writing operation and light emitting operation are similar to those described with reference to FIG. 97, and therefore the description thereof will be omitted.

An erase operation will now be described. During the erase operation, an H-level signal is input to the second scanning line 80510. Then, the erase transistor 80509 is turned on, and the gate and the first electrode of the driving transistor can be set to the same potential. That is, the driving transistor 80502
It is possible to set the Vgs of the driving transistor 80502 to 0 V. In this way, the driving transistor 80502 can be forcibly turned off.

The configuration and operation of a pixel called a threshold voltage compensation type will be described below. A threshold voltage compensation type pixel can be applied to digital time gray scale driving and analog gray scale driving.

Figure 100 shows an example of the configuration of a pixel called a threshold voltage correction type.

The pixel shown in FIG. 100 includes a driving transistor 80600, a first switch 80601, a second switch 80602, a third switch 80603, a first capacitor element 80604, a second
The driving transistor 806 includes a capacitor element 80605 and a light emitting element 80620.
The gate of the driving transistor 80600 is connected to a signal line 80611 via a first capacitor element 80604 and a first switch 80601 in this order. The gate of the driving transistor 80600 is connected to a power supply line 80612 via a second capacitor element 80605.
The first electrode of the driving transistor 806 is connected to a power supply line 80612.
A second electrode of the driving transistor 80600 is connected to a first electrode of the light-emitting element 80620 via a third switch 80603.
The light emitting element 806 is connected to the gate of the driving transistor 80600 via a gate electrode 802.
The second electrode of 20 corresponds to the common electrode 80621.

A low power supply potential is set to the second electrode of the light-emitting element 80620. Note that the low power supply potential is a potential that satisfies the condition of low power supply potential<high power supply potential with respect to a high power supply potential set to the power supply line 80612, and the low power supply potential may be set to, for example, GND or 0 V.
The potential difference between the high power supply potential and the low power supply potential is applied to the light emitting element 80620,
In order to pass a current through the gate electrode 80620 to cause the light emitting element 80620 to emit light, the potentials of the high power supply potential and the low power supply potential are set so that the potential difference between them is equal to or greater than the forward threshold voltage of the light emitting element 80620. The second capacitor 80605 can be omitted by substituting the gate capacitance of the driving transistor 80600. Regarding the gate capacitance of the driving transistor 80600, a capacitance may be formed in a region where the source region, the drain region, or the LDD region overlaps with the gate electrode, or a capacitance may be formed between the channel region and the gate electrode. The first switch 80601, the second switch 80602, and the third switch 80603 are controlled to be turned on and off by the first scanning line 80613, the second scanning line 80614, and the third scanning line 80614, respectively.

Regarding the driving method of the pixel shown in FIG. 100, the operation period is an initialization period, a data writing period,
The explanation will be divided into a threshold acquisition period and a light emission period.

During the initialization period, the second switch 80602 and the third switch 80603 are turned on.
Then, the potential of the gate of the driving transistor 80600 becomes lower than at least the potential of the power supply line 80612. At this time, the first switch 80601 may be on or off. Note that the initialization period is not necessarily required.

During the threshold acquisition period, a pixel is selected by the first scanning line 80613. That is, the first switch 80601 is turned on, and a certain constant voltage is input from the signal line 80611. At this time, the second switch 80602 is turned on, and the third switch 80603 is turned off. Therefore, the driving transistor 80600 is diode-connected, and the second electrode and gate of the driving transistor 80600 are in a floating state. Then,
The potential of the gate of the driving transistor 80600 is a value obtained by subtracting the threshold voltage of the driving transistor 80600 from the potential of the power supply line 80612.
The threshold voltage of the driving transistor 80600 is held in the second capacitance element 804.
A potential difference between the potential of the gate of the driving transistor 80600 and a constant voltage input from a signal line 80611 is held in a transistor 0605 .

In the data writing period, a video signal (voltage) is input from the signal line 80611. At this time, the first switch 80601 remains on, the second switch 80602 is turned off, and the third switch 80603 remains off.
Since the gate of the driving transistor 80600 is in a floating state, the potential of the gate of the driving transistor 80600 changes according to the potential difference between a constant voltage input to the signal line 80611 during a threshold acquisition period and a video signal input to the signal line 80611 during a data write period. For example, the capacitance value of the first capacitor 80604<<the capacitance value of the second capacitor 80605.
If the capacitance value of 0605 is 0605, the driving transistor 80600 during the data writing period
The gate potential of the driving transistor 80600 is approximately equal to the sum of the potential difference (amount of change) between the potential of the signal line 80611 during the threshold acquisition period and the potential of the signal line 80611 during the data write period, and the value obtained by subtracting the threshold voltage of the driving transistor 80600 from the potential of the power supply line 80612.
That is, the potential of the gate of the driving transistor 80600 is
This is a potential obtained by correcting the threshold voltage of 0.

During the light emission period, the potential difference between the gate of the driving transistor 80600 and the power supply line 80612 (
A current according to the first switch 806 flows through the light emitting element 80620.
01 is turned off, the second switch 80602 remains off, and the third switch 8060
The current flowing through the light emitting element 80620 is
It is constant regardless of the threshold voltage of 0.

Note that the pixel configuration shown in Fig. 100 is not limited to this. For example, a switch, a resistor, a capacitor, a transistor, a logic circuit, or the like may be newly added to the pixel shown in Fig. 100. For example, the second switch 80602 may be configured with a P-channel transistor or an N-channel transistor, the third switch 80603 may be configured with a transistor having a polarity different from that of the second switch 80602, and the second switch 80602 and the third switch 80603 may be controlled by the same scan line.

The configuration and operation of a pixel called a current input type will be described below. A current input type pixel can be applied to digital gray scale driving and analog gray scale driving.

Figure 101 shows an example of the configuration of a pixel called a current input type.

The pixel shown in FIG. 101 includes a driving transistor 80700, a first switch 80701, a second switch 80702, a third switch 80703, a capacitor element 80704, and a light-emitting element 80730. The gate of the driving transistor 80700 is connected to the second switch 80701.
The gate of the driving transistor 80700 is connected to a power supply line 807 through a capacitor 80704.
The first electrode of the driving transistor 80700 is connected to the power supply line 80712.
The second electrode of the driving transistor 80700 is connected to the first switch 807
The second transistor 80700 is connected to a power supply line 80712 via a gate electrode 80711.
The electrode is connected to a first electrode of the light-emitting element 80730 via the third switch 80703. The second electrode of the light-emitting element 80730 corresponds to a common electrode 80731.

A low power supply potential is set to the second electrode of the light-emitting element 80730. Note that the low power supply potential is a potential that satisfies the condition of low power supply potential<high power supply potential with respect to a high power supply potential set to the power supply line 80712, and the low power supply potential may be set to, for example, GND or 0 V.
The potential difference between the high power supply potential and the low power supply potential is applied to the light emitting element 80730,
In order to make the light emitting element 80730 emit light by passing a current through the gate electrode 80730, the potentials of the high power supply potential and the low power supply potential are set so that the potential difference between them is equal to or greater than the forward threshold voltage of the light emitting element 80730. Note that the capacitor 80704 can be omitted by substituting the gate capacitance of the driving transistor 80700. Regarding the gate capacitance of the driving transistor 80700, a capacitance may be formed in a region where the source region, the drain region, or the LDD region overlaps with the gate electrode, or a capacitance may be formed between the channel region and the gate electrode. Note that the first switch 80701, the second switch 80702, and the third switch 80703 are controlled to be turned on and off by the first scan line 80713, the second scan line 80714, and the third scan line 80734, respectively.

The method of driving the pixel shown in FIG. 101 will be described by dividing the operation period into a data writing period and a light emission period.

In the data writing period, a pixel is selected by the first scanning line 80713. That is,
The first switch 80701 is turned on, and a current is input as a video signal from the signal line 80711. At this time, the second switch 80702 is turned on, and the third switch 80703 is turned off. Therefore, the potential of the gate of the driving transistor 80700 becomes a potential corresponding to the video signal. In other words, the capacitor 80704 holds a voltage between the gate electrode and source electrode of the driving transistor 80700 such that the driving transistor 80700 passes the same current as the video signal.

Next, in the light emission period, the first switch 80701 and the second switch 80702 are turned off, and the third switch 80703 is turned on. Therefore, a current having the same value as that of a video signal flows through the light emitting element 80730.

Note that the pixel configuration shown in Fig. 101 is not limited to this. For example, a switch, a resistor, a capacitor, a transistor, a logic circuit, or the like may be newly added to the pixel shown in Fig. 101. For example, the first switch 80701 may be configured with a P-channel transistor or an N-channel transistor, the second switch 80702 may be configured with a transistor having the same polarity as the first switch 80701, and the first switch 80701 and the second switch 80702 may be controlled by the same scan line. The second switch 80702 may be disposed between the gate of the driving transistor 80700 and the signal line 80711.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 13)
In this embodiment, a pixel structure of a display device will be described, in particular, a pixel structure of a display device using an organic EL element will be described.

Fig. 102A is an example of a top view (layout diagram) of a pixel having two transistors in one pixel, and Fig. 102B is an example of a cross-sectional view of a portion XX' shown in Fig. 102A.

FIG. 102A shows a first transistor 60105, a first wiring 60106, a second wiring 60107, a second transistor 60108, a third wiring 60111, and a counter electrode 6011.
2, a capacitor 60113, a pixel electrode 60115, a partition wall 60116, and an organic conductive film 601
17, an organic thin film 60118, and a substrate 60119. Note that it is preferable that the first transistor 60105 is used as a switching transistor, the first wiring 60106 is used as a gate signal line, the second wiring 60107 is used as a source signal line, the second transistor 60108 is used as a driving transistor, and the third wiring 60111 is used as a current supply line.

A gate electrode of the first transistor 60105 is electrically connected to a first wiring 60106, one of a source electrode and a drain electrode of the first transistor 60105 is electrically connected to a second wiring 60107, and the other of the source electrode and the drain electrode of the first transistor 60105 is electrically connected to a gate electrode of a second transistor 60108 and a capacitor 60113.
The first transistor 60105 is electrically connected to one electrode of the first transistor 60105. Note that the gate electrode of the first transistor 60105 is composed of a plurality of gate electrodes. This can reduce leakage current when the first transistor 60105 is in an off state.

One of the source electrode and the drain electrode of the second transistor 60108 is connected to the third wiring 60
111, and the other of the source electrode and the drain electrode of the second transistor 60108 is electrically connected to the pixel electrode 60115. In this manner, the current flowing through the pixel electrode 60115 can be controlled by the second transistor 60108.

An organic conductive film 60117 is provided on the pixel electrode 60115, and an organic thin film 601
On the organic thin film 60118 (organic compound layer),
An opposing electrode 60112 is provided. The opposing electrode 60112 may be formed in a solid form so as to be commonly connected to all pixels, or may be formed in a pattern using a shadow mask or the like.

Light emitted from the organic thin film 60118 (organic compound layer) is transmitted through either the pixel electrode 60115 or the counter electrode 60112 .

In FIG. 102B, when light is emitted toward the pixel electrode side, that is, the side where the transistors and the like are formed, it is called bottom emission, and when light is emitted toward the opposing electrode side, it is called top emission.

In the case of bottom emission, the pixel electrode 60115 is preferably formed from a transparent conductive film.
Conversely, in the case of top emission, the counter electrode 60112 is preferably formed from a transparent conductive film.

In a light-emitting device for color display, EL elements having the respective luminescent colors of R, G, and B may be painted separately, or single-color EL elements may be painted in a solid form and R, G, and B may be separated by color filters.
It is also possible to obtain B light emission.

Note that the configuration shown in Fig. 102 is merely one example, and various configurations can be used with respect to the pixel layout, cross-sectional configuration, stacking order of electrodes of the EL element, etc., other than the configuration shown in Fig. 102. Also, for the light-emitting layer, in addition to the element constituted by the illustrated organic thin film, various elements can be used, such as a crystalline element such as an LED, an element constituted by an inorganic thin film, etc.

Fig. 103A is an example of a top view (layout diagram) of a pixel having three transistors in one pixel, and Fig. 103B is an example of a cross-sectional view of a portion XX' shown in Fig. 103A.

FIG. 103A shows a substrate 60200, a first wiring 60201, a second wiring 60202, a third wiring 60203, a fourth wiring 60204, a first transistor 60205, a second transistor 60206, a third transistor 60207, a pixel electrode 60208, a partition wall 60209, and a semiconductor device 60300.
211, an organic conductive film 60212, an organic thin film 60213 and a counter electrode 60214 are shown.
The first wiring 60201 serves as a source signal line, the second wiring 60202 serves as a write gate signal line, the third wiring 60203 serves as an erase gate signal line, and the fourth wiring 602
It is preferable that 04 is used as a current supply line, the first transistor 60205 as a switching transistor, the second transistor 60206 as an erasing transistor, and the third transistor 60207 as a driving transistor.

The gate electrode of the first transistor 60205 is electrically connected to the second wiring 60202, one of the source electrode and the drain electrode of the first transistor 60205 is electrically connected to the first wiring 60201, and the other of the source electrode and the drain electrode of the first transistor 60205 is electrically connected to the gate electrode of the third transistor 60207. Note that the gate electrode of the first transistor 60205 is composed of a plurality of gate electrodes. This can reduce leakage current when the first transistor 60205 is in an off state.

The gate electrode of the second transistor 60206 is electrically connected to the third wiring 60203, one of the source electrode and the drain electrode of the second transistor 60206 is electrically connected to the fourth wiring 60204, and the other of the source electrode and the drain electrode of the second transistor 60206 is electrically connected to the gate electrode of the third transistor 60207. Note that the gate electrode of the second transistor 60206 is composed of a plurality of gate electrodes. This can reduce leakage current when the second transistor 60206 is in an off state.

One of the source electrode and the drain electrode of the third transistor 60207 is connected to the fourth wiring 60
204, and the other of the source electrode and the drain electrode of the third transistor 60207 is electrically connected to the pixel electrode 60208. In this manner, the current flowing through the pixel electrode 60208 can be controlled by the third transistor 60207.

An organic conductive film 60212 is provided on the pixel electrode 60208, and an organic thin film 602
On the organic thin film 60213 (organic compound layer),
An opposing electrode 60214 is provided. The opposing electrode 60214 may be formed in a solid form so as to be commonly connected to all pixels, or may be formed in a pattern using a shadow mask or the like.

Light emitted from the organic thin film 60213 (organic compound layer) is transmitted through either the pixel electrode 60208 or the counter electrode 60214 .

In FIG. 103B, when light is emitted toward the pixel electrode side, that is, the side where the transistors and the like are formed, it is called bottom emission, and when light is emitted toward the opposing electrode side, it is called top emission.

In the case of bottom emission, the pixel electrode 60208 is preferably formed from a transparent conductive film.
Conversely, in the case of top emission, the counter electrode 60214 is preferably formed from a transparent conductive film.

In a light-emitting device for color display, EL elements having the respective luminescent colors of R, G, and B may be painted separately, or single-color EL elements may be painted in a solid form and R, G, and B may be separated by color filters.
It is also possible to obtain B light emission.

Note that the configuration shown in Fig. 103 is merely one example, and various configurations can be used with respect to the pixel layout, cross-sectional configuration, stacking order of electrodes of the EL element, etc., other than the configuration shown in Fig. 103. Also, for the light-emitting layer, in addition to the element constituted by the illustrated organic thin film, various elements can be used, such as a crystalline element such as an LED, an element constituted by an inorganic thin film, etc.

Fig. 104A is an example of a top view (layout diagram) of a pixel having four transistors in one pixel, and Fig. 104B is an example of a cross-sectional view of a portion XX' shown in Fig. 104A.

FIG. 104A illustrates a substrate 60300, a first wiring 60301, a second wiring 60302, a third wiring 60303, a fourth wiring 60304, a first transistor 60305, a second transistor 60306, a third transistor 60307, and a fourth transistor 60308.
, pixel electrode 60309, fifth wiring 60311, sixth wiring 60312, partition wall 60321
, an organic conductive film 60322, an organic thin film 60323, and a counter electrode 60324 are shown.
The first wiring 60301 is used as a source signal line, the second wiring 60302 is used as a write gate signal line, the third wiring 60303 is used as an erase gate signal line, and the fourth wiring 60304 is used as a write gate signal line.
04 is a reverse bias signal line, the first transistor 60305 is a switching transistor, the second transistor 60306 is an erasing transistor, and the third transistor 60307 is a
The transistor 60307 is a driving transistor, and the fourth transistor 60308
is preferably used as a reverse bias transistor, the fifth wiring 60311 as a current supply line, and the sixth wiring 60312 as a reverse bias power supply line.

The gate electrode of the first transistor 60305 is electrically connected to the second wiring 60302, one of the source electrode and the drain electrode of the first transistor 60305 is electrically connected to the first wiring 60301, and the other of the source electrode and the drain electrode of the first transistor 60305 is electrically connected to the gate electrode of the third transistor 60307. Note that the gate electrode of the first transistor 60305 is composed of a plurality of gate electrodes. This can reduce leakage current when the first transistor 60305 is in an off state.

The gate electrode of the second transistor 60306 is electrically connected to the third wiring 60303, one of the source electrode and the drain electrode of the second transistor 60306 is electrically connected to the fifth wiring 60311, and the other of the source electrode and the drain electrode of the second transistor 60306 is electrically connected to the gate electrode of the third transistor 60307. Note that the gate electrode of the second transistor 60306 is composed of a plurality of gate electrodes. This can reduce leakage current when the second transistor 60306 is in an off state.

One of the source electrode and the drain electrode of the third transistor 60307 is connected to the fifth wiring 60
311, and the other of the source electrode and the drain electrode of the third transistor 60307 is electrically connected to the pixel electrode 60309. In this manner, the current flowing through the pixel electrode 60309 can be controlled by the third transistor 60307.

A gate electrode of the fourth transistor 60308 is electrically connected to the fourth wiring 60304, one of a source electrode and a drain electrode of the fourth transistor 60308 is electrically connected to the sixth wiring 60312, and the other of the source electrode and the drain electrode of the fourth transistor 60308 is electrically connected to the pixel electrode 60309. In this manner, the potential of the pixel electrode 60309 can be controlled by the fourth transistor 60308, so that a reverse bias can be applied to the organic conductor film 60322 and the organic thin film 60323. By applying a reverse bias to a light-emitting element constituted by the organic conductor film 60322, the organic thin film 60323, etc., the reliability of the light-emitting element can be greatly improved.

An organic conductive film 60322 is provided on the pixel electrode 60309, and an organic thin film 603
On the organic thin film 60323 (organic compound layer),
An opposing electrode 60324 is provided. The opposing electrode 60324 may be formed in a solid form so as to be commonly connected to all pixels, or may be formed in a pattern using a shadow mask or the like.

Light emitted from the organic thin film 60323 (organic compound layer) is transmitted through either the pixel electrode 60309 or the counter electrode 60324 .

In FIG. 104B, when light is emitted toward the pixel electrode side, that is, the side where the transistors and the like are formed, it is called bottom emission, and when light is emitted toward the opposing electrode side, it is called top emission.

In the case of bottom emission, the pixel electrode 60309 is preferably formed from a transparent conductive film.
Conversely, in the case of top emission, the counter electrode 60324 is preferably formed from a transparent conductive film.

In a light-emitting device for color display, EL elements having the respective luminescent colors of R, G, and B may be painted separately, or single-color EL elements may be painted in a solid form and R, G, and B may be separated by color filters.
It is also possible to obtain B light emission.

Note that the configuration shown in Fig. 104 is merely one example, and various configurations can be used with respect to the pixel layout, cross-sectional configuration, stacking order of electrodes of the EL element, etc., other than the configuration shown in Fig. 104. Also, for the light-emitting layer, in addition to the element constituted by the illustrated organic thin film, various elements can be used, such as a crystalline element such as an LED, an element constituted by an inorganic thin film, etc.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 14)
In this embodiment, the structure of an EL element will be described, and in particular, the structure of an organic EL element will be described.

The structure of a mixed junction EL element will be described. As an example, a structure (hereinafter referred to as a mixed junction EL element) having a layer (mixed layer) in which a plurality of materials such as a hole injection material, a hole transport material, a light emitting material, an electron transport material, and an electron injection material are mixed, instead of a laminate structure in which a hole injection layer made of a hole injection material, a hole transport layer made of a hole transport material, a light emitting material, an electron transport layer made of an electron transport material, and an electron injection layer made of an electron injection material are clearly distinguished from each other, will be described.

105(A), (B), (C) and (D) are schematic diagrams showing the structure of a mixed junction EL element. Note that the layer sandwiched between an anode 190101 and a cathode 190102 corresponds to the EL layer.

FIG. 105(A) shows an EL layer including a hole transport region 190103 made of a hole transport material and an electron transport region 190104 made of an electron transport material, the hole transport region 190103 being located closer to the anode than the electron transport region 190104, and a mixed region 190104 containing both the hole transport material and the electron transport material being located between the hole transport region 190103 and the electron transport region 190104.
105 is provided.

It is noted that in the direction from the anode 190101 to the cathode 190102, the concentration of the hole transport material in the mixed region 190105 decreases and the concentration of the electron transport material in the mixed region 190105 increases.

The method of setting the concentration gradient can be freely set. For example, the hole transport region 190103 made of only the hole transport material may not exist, and the concentration ratio of each functional material may change (having a concentration gradient) inside the mixed region 190105 containing both the hole transport material and the electron transport material. Alternatively, the hole transport region 190103 made of only the hole transport material may be configured to have a concentration gradient.
Alternatively, the concentration ratio of each functional material may be changed (having a concentration gradient) within the mixed region 190105 containing both the hole transport material and the electron transport material, without the hole transport material 103 and the electron transport region 190104 consisting only of the electron transport material. Alternatively, the concentration ratio may be changed depending on the distance from the anode or cathode. The change in the concentration ratio may be continuous.

The mixed region 190105 has a region 190106 to which a light-emitting material is added. The light-emitting color of the EL element can be controlled by the light-emitting material. The light-emitting material can trap carriers. As the light-emitting material, metal complexes containing a quinoline skeleton, metal complexes containing a benzoxazole skeleton, metal complexes containing a benzothiazole skeleton, and various fluorescent dyes can be used. By adding these light-emitting materials, the light-emitting color of the EL element can be controlled.

For the anode 190101, an electrode material with a large work function is preferably used in order to efficiently inject holes. For example, _a transparent electrode such as tin-doped indium oxide (ITO), zinc-doped indium oxide (IZO), ZnO, _SnO2 , or _In2O3 can be used. Alternatively, if there is no need for light transmission, the anode 190101 may be an opaque metal material.

Aromatic amine compounds and the like can be used as hole transport materials.

As the electron transport material, a metal complex having a quinoline derivative, 8-quinolinol or a derivative thereof as a ligand (particularly, tris(8-quinolinolite)aluminum (Alq ₃ )), or the like can be used.

For the cathode 190102, an electrode material having a small work function is preferably used in order to efficiently inject electrons. Metals such as aluminum, indium, magnesium, silver, calcium, barium, and lithium can be used alone. Alternatively, alloys of these metals or alloys of these metals with other metals may be used.

A schematic diagram of an EL element having a different structure from that shown in FIG.
The same parts as those in 05(A) are designated by the same reference numerals, and the explanation thereof will be omitted.

In FIG. 105B, there is no region doped with light-emitting material. However, the electron transport region 19
As a material to be added to the layer 0104, a material having both electron transporting and luminescent properties (electron transporting luminescent material), for example, tris(8-quinolinolite)aluminum (Alq ₃ ) is used, which can emit light.

Alternatively, a material having both hole transport properties and light emitting properties (hole transport light emitting material) may be used as the material to be added to the hole transport region 190103.

FIG. 105(C) is a schematic diagram of an EL element having a different structure from those in FIG. 105(A) and FIG. 105(B).
The same parts as those in FIG. 105(A) and FIG. 105(B) are denoted by the same reference numerals.
The explanation will be omitted.

105C, a region 190107 is formed in the mixed region 190105 to which a hole blocking material having a larger energy difference between the highest occupied molecular orbital and the lowest occupied molecular orbital than that of the hole transporting material is added. The region 190107 to which the hole blocking material is added is located closer to the cathode 19010 than the region 190106 to which the light emitting material is added in the mixed region 190105.
By disposing the region 190107 on the second side, the recombination rate of carriers can be increased, and the light emission efficiency can be increased. The above-mentioned configuration in which the region 190107 to which the hole blocking material is added is particularly effective in an EL element that utilizes light emission (phosphorescence) due to triple photoexcitons.

Fig. 105(D) shows a schematic diagram of an EL element having a different structure from those shown in Fig. 105(A), Fig. 105(B) and Fig. 105(C). Note that the same parts as those shown in Fig. 105(A), Fig. 105(B) and Fig. 105(C) are designated by the same reference numerals, and the description thereof will be omitted.

105D, a region 190108 is formed in the mixed region 190105 to which an electron blocking material having a larger energy difference between the highest occupied molecular orbital and the lowest occupied molecular orbital than that of the electron transport material is added. The region 190108 to which the electron blocking material is added is closer to the anode 19010 than the region 190106 to which the light emitting material is added in the mixed region 190105.
By disposing the region 190108 on the first side, the recombination rate of carriers can be increased, and the light emission efficiency can be increased. The above-mentioned configuration in which the region 190108 to which the electron blocking material is added is particularly effective in an EL element that utilizes light emission (phosphorescence) due to triple photoexcitons.

FIG. 105(E) is a cross-sectional view of FIG. 105(A), FIG. 105(B), FIG. 105(C) and FIG. 105(D).
FIG. 105(E) is a schematic diagram showing the configuration of a mixed junction EL element different from that shown in FIG.
105(E) shows an example of a configuration in which a region 190109 to which a metal material is added is provided in the portion of the EL layer that contacts the electrode of the L element. In FIG. 105(E), the same parts as those in FIG. 105(A) to FIG. 105(D) are indicated by the same reference numerals and the description thereof is omitted. The configuration shown in FIG. 105(E) has, for example, a cathode 1
The cathode 190102 may be made of MgAg (Mg-Ag alloy), and the electron transport region 190104 to which an electron transport material is added may have a region 190109 to which an Al (aluminum) alloy is added in a region in contact with the cathode 190102. With the above-mentioned configuration, oxidation of the cathode can be prevented, and the efficiency of electron injection from the cathode can be increased. Thus, the life of the mixed junction type EL element can be extended. The driving voltage can also be reduced.

The above-mentioned mixed junction EL element can be fabricated by a co-evaporation method or the like.

In the mixed junction EL element as shown in Figure 105(A) to Figure 105(E), there is no clear layer interface, so that the charge accumulation can be reduced, the lifetime can be extended, and the driving voltage can be reduced.

It should be noted that the configurations shown in FIGS. 105(A) to 105(E) can be freely combined and implemented.

The structure of the mixed junction EL element is not limited to this, and any known structure can be freely used.

The organic material constituting the EL layer of the EL element may be a low molecular weight material or a high molecular weight material. Alternatively, both of these materials may be used. When a low molecular weight material is used as the organic compound material, the film can be formed by a deposition method. On the other hand, when a high molecular weight material is used as the EL layer, the high molecular weight material is dissolved in a solvent and the film can be formed by a spin coating method or an inkjet method.

The EL layer may be made of a medium molecular weight material. In this specification, a medium molecular weight organic light emitting material refers to an organic light emitting material that does not have sublimation properties and has a degree of polymerization of about 20 or less. When a medium molecular weight material is used as the EL layer, the film can be formed by an inkjet method or the like.

In addition, low molecular weight materials, high molecular weight materials, and medium molecular weight materials may be used in combination.

The EL element may be either one that utilizes light emission from singlet excitons (fluorescence) or one that utilizes light emission from triplet excitons (phosphorescence).

Next, we will explain the deposition apparatus for manufacturing display devices with reference to the drawings.

The display device may be manufactured by forming an EL layer. The EL layer is formed by at least partially containing a material that exhibits electroluminescence. The EL layer may be composed of a plurality of layers with different functions. In this case, the EL layer may be composed of a combination of layers with different functions, which are also called hole injection transport layer, light emitting layer, electron injection transport layer, etc.

FIG. 10 shows the configuration of a deposition apparatus for forming an EL layer on an element substrate on which a transistor is formed.
6. This deposition apparatus has multiple processing chambers connected to transfer chambers 190260 and 190261. The processing chambers include a load chamber 190262 for supplying substrates, an unload chamber 190263 for recovering substrates, a heat treatment chamber 190268, a plasma treatment chamber 190272, an EL
Film forming chambers 190269 to 190275 for depositing materials, as one electrode of the EL element,
A film forming processing chamber 1902 for forming an aluminum or aluminum-based conductive film
76. Gate valves 190277a to 190277a are provided between the transfer chamber and each processing chamber.
The pressure in each processing chamber can be controlled independently, preventing cross-contamination between the processing chambers.

The substrate introduced from the load chamber 190262 into the transfer chamber 190260 is carried into a predetermined processing chamber by a rotatable arm-type transfer means 190266. The substrate is transferred from one processing chamber to another processing chamber by the transfer means 190266. The transfer chamber 190260 and the transfer chamber 190261 are connected by a film forming processing chamber 190270, where the transfer means 19026
The substrate is transferred between the substrate holder 190267 and the substrate transfer means 190267.

Each processing chamber connected to the transfer chamber 190260 and the transfer chamber 190261 is maintained in a reduced pressure state. Therefore, in this deposition apparatus, the EL layer deposition process is performed continuously on the substrate without exposing it to the atmosphere. Since the display panel after the EL layer deposition process may deteriorate due to water vapor, etc., in this deposition apparatus, a sealing process chamber 190265 is connected to the transfer chamber 190261 to perform a sealing process before exposing it to the atmosphere in order to maintain quality. Since the sealing process chamber 190265 is maintained at atmospheric pressure or a reduced pressure close to it, the transfer chamber 1902
An intermediate processing chamber 190264 is also provided between the chamber 61 and the sealing processing chamber 190265. The intermediate processing chamber 190264 is provided for transferring the substrate and for buffering the pressure between the chambers.

The load chamber, unload chamber, transfer chamber and film forming chamber are provided with exhaust means for maintaining the interior of the chamber at a reduced pressure. As the exhaust means, various types of vacuum pumps such as a dry pump, a turbo molecular pump and a diffusion pump can be used.

106, the number and configuration of the processing chambers connected to the transfer chamber 190260 and the transfer chamber 190261 can be appropriately combined according to the laminated structure of the EL element. An example of such a combination is shown below.

The heating treatment chamber 190268 first heats the substrate on which the lower electrode or the insulating partition wall is formed to perform degassing treatment. The plasma treatment chamber 190272 performs rare gas or oxygen plasma treatment on the surface of the base electrode. This plasma treatment is performed to clean the surface, stabilize the surface state, and stabilize the physical or chemical state of the surface (e.g., work function, etc.).

The film forming treatment chamber 190269 is a treatment chamber for forming an electrode buffer layer that contacts one electrode of the EL element. The electrode buffer layer has a carrier injection property (hole injection or electron injection).
The electrode buffer layer is a layer that suppresses the occurrence of short circuits or dark spot defects in the EL element. Typically, the electrode buffer layer is made of an organic/inorganic mixed material, has a resistivity of 5×10 ⁴ to 1×10 ⁶ Ωcm, and has a resistivity of 30 to 300 Ωcm.
The film is formed to a thickness of 100 nm. The film formation chamber 190271 is a treatment chamber for forming a hole transport layer.

The light-emitting layer in an EL element has a different structure depending on whether it emits a single color or white light. It is preferable to arrange the film-forming chamber in the deposition apparatus accordingly. For example,
When forming three types of EL elements with different luminescent colors on a display panel, it is necessary to form a luminescent layer corresponding to each luminescent color. In this case, the film formation treatment chamber 190270 is used for forming a first luminescent layer, the film formation treatment chamber 190273 is used for forming a second luminescent layer, and the film formation treatment chamber 1902
The third light-emitting layer may be formed in the chamber 74. By separating the film-forming process chambers for each light-emitting layer, cross contamination due to different light-emitting materials can be prevented, and the throughput of the film-forming process can be improved.

Alternatively, three types of EL materials with different emission colors may be sequentially deposited in the deposition treatment chambers 190270, 190273, and 190274. In this case, a shadow mask is used and deposition is performed by shifting the mask according to the region to be deposited.

When forming an EL element that emits white light, light-emitting layers of different colors are stacked vertically. In this case, too, the element substrate can be moved sequentially through the deposition chambers to deposit each light-emitting layer. Alternatively, different light-emitting layers can be deposited consecutively in the same deposition chamber.

An electrode is formed on the EL layer in the film formation treatment chamber 190276. The electrode can be formed by electron beam evaporation or sputtering, but it is preferable to use resistance heating evaporation.

The element substrate on which the electrodes have been formed is passed through an intermediate processing chamber 190264 and then into a sealing processing chamber 1902.
The sealing process chamber 190265 is filled with an inert gas such as helium, argon, neon, or nitrogen, and a sealing plate is attached to the side of the element substrate on which the EL layer is formed in that atmosphere to seal the substrate. In the sealed state, the space between the element substrate and the sealing plate may be filled with an inert gas or may be filled with a resin material. The sealing process chamber 190265 is equipped with a dispenser for applying a sealant, or a mechanical element such as a fixed stage or arm for fixing the sealing plate opposite the element substrate, a dispenser or spin coater for filling the resin material, or the like.

FIG. 107 shows the internal structure of the film forming chamber. The film forming chamber is kept under reduced pressure.
In FIG. 7, the inside space between a top plate 190391 and a bottom plate 190392 is an indoor space that is maintained in a reduced pressure state.

The processing chamber is provided with one or more evaporation sources. This is because it is preferable to provide multiple evaporation sources when forming multiple layers with different compositions or when co-evaporating different materials. In FIG. 107, evaporation sources 190381a, 190381b, and 190381c are attached to an evaporation source holder 190380. The evaporation source holder 190380 is held by an articulated arm 190383. The articulated arm 190383 can freely move the position of the evaporation source holder 190380 within its movable range by expanding and contracting the joints. Alternatively, a distance sensor 190382 is provided on the evaporation source holder 190380, and the distance sensor 190382 detects the evaporation source 19038
The optimum gap during deposition may be controlled by monitoring the gap between 1a to 190381c and the substrate 190389. In that case, the multi-joint arm may be a multi-joint arm that can also be displaced in the vertical direction (Z direction).

The substrate stage 190386 and the substrate chuck 190387 form a pair and support the substrate 190389.
The substrate stage 190386 may be configured to incorporate a heater so that the substrate 190389 can be heated. The substrate 190389 is fixed to the substrate stage 190386 and is moved in and out by loosening a substrate chuck 190387. For deposition, a shadow mask 190390 having openings corresponding to the pattern to be deposited can be used as necessary. In that case, the shadow mask 190390 is arranged between the substrate 190389 and the evaporation source 190389.
The shadow mask should be placed between 0381a and 190381c.
is fixed to the substrate 190389 in close contact or at a fixed distance by a mask chuck 190388. When alignment of the shadow mask 190390 is required, the alignment is performed by disposing a camera in the processing chamber and providing the mask chuck 190388 with a positioning means that moves slightly in the XY-θ directions.

A vapor deposition material supplying means for continuously supplying a vapor deposition material to the vapor deposition source 190381 is added to the vapor deposition source 190381. The vapor deposition material supplying means includes material supply sources 190385a, 190385b, and 190385c that are disposed at a position away from the vapor deposition source 190381, and a material supply pipe 190384 that connects between the two. Typically, the material supply sources 190385a, 190385b
, 190385c are provided corresponding to the evaporation source 190381. In the case of FIG.
The material supply source 190385a corresponds to the evaporation source 190381a.
The same is true for material supply source 190385c and evaporation source 190381c, and material supply source 190385b and evaporation source 190381b.

The deposition material can be supplied by an air current transport method, an aerosol method, or the like. The air current transport method transports the fine powder of the deposition material on an air current, and transports it to the evaporation source 190381 using an inert gas or the like. The aerosol method transports a raw material liquid in which the deposition material is dissolved or dispersed in a solvent, turns it into an aerosol using a sprayer, and performs deposition while vaporizing the solvent in the aerosol. In either case, the evaporation source 190381 is provided with a heating means, and the transported deposition material is evaporated to form a film on the substrate 190389. In the case of FIG. 107, the material supply pipe 19
The 0384 is made of a thin tube that can be flexibly bent and has enough rigidity so that it will not deform even under reduced pressure.

When the air current transport method or the aerosol method is applied, the pressure in the film formation processing chamber is atmospheric pressure or lower, and preferably, the film formation is performed under reduced pressure of 133 Pa to 13,300 Pa.
The film forming chamber can be filled with an inert gas such as helium, argon, neon, krypton, xenon, or nitrogen, or the pressure can be adjusted while supplying the gas (while simultaneously evacuating the gas). In the film forming chamber where an oxide film is formed, a gas such as oxygen or nitrous oxide may be introduced to create an oxidizing atmosphere. Alternatively, a gas such as hydrogen may be introduced to create a reducing atmosphere in the film forming chamber where an organic material is evaporated.

As another method for supplying the deposition material, a screw may be provided in the material supply pipe 190384 to continuously push out the deposition material toward the evaporation source.

This deposition apparatus can continuously form a film with good uniformity even on a large-screen display panel. Since it is not necessary to replenish the deposition material every time the deposition source runs out of the deposition material, the throughput can be improved.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 15)
In this embodiment, the structure of an EL element will be described, and in particular, the structure of an inorganic EL element will be described.

Inorganic EL elements are classified into dispersion-type inorganic EL elements and thin-film-type inorganic EL elements according to their element structure. The former have an electroluminescent layer in which particles of a luminescent material are dispersed in a binder, while the latter have an electroluminescent layer made of a thin film of a luminescent material, but they are common in that they require electrons accelerated by a high electric field. The mechanisms of light emission that can be obtained include donor-acceptor recombination light emission that utilizes the donor level and acceptor level, and localized light emission that utilizes the inner-shell electron transition of metal ions. Generally, in dispersion-type inorganic EL, donor-
In the case of thin-film inorganic EL devices, the emission is of the acceptor recombination type, whereas in the case of thin-film inorganic EL devices, the emission is of the localized type.

Luminescent materials are composed of a base material and an impurity element that serves as the luminescent center. By changing the impurity element contained, it is possible to obtain luminescence of various colors. Various methods such as a solid-phase method or a liquid-phase method (coprecipitation method) can be used to prepare luminescent materials. Alternatively, a liquid-phase method such as a spray pyrolysis method, a double decomposition method, a method using a pyrolysis reaction of a precursor, a reverse micelle method or a method combining these methods with high-temperature baking, or a freeze-drying method can also be used.

In the solid phase method, the base material and the impurity element or a compound containing the impurity element are weighed and mixed in a mortar.
This method involves heating and sintering in an electric furnace to induce a reaction and incorporate impurity elements into the base material. The sintering temperature is preferably 700 to 1500°C. If the temperature is too low, the solid-phase reaction will not proceed, and if the temperature is too high, the base material will decompose. Although sintering may be performed in powder form, it is preferable to sinter in pellet form. Although sintering at a relatively high temperature is required, this is a simple method, which provides good productivity and is suitable for mass production.

The liquid phase method (coprecipitation method) is a method in which a host material or a compound containing the host material is reacted with an impurity element or a compound containing the impurity element in a solution, dried, and then fired. The particles of the luminescent material are uniformly distributed and have a small particle size, so the reaction can proceed even at a low firing temperature.

The host material used for the light-emitting material may be a sulfide, an oxide, or a nitride. Examples of sulfides that may be used include zinc sulfide (ZnS), cadmium sulfide (CdS), calcium sulfide (CaS), yttrium sulfide (Y ₂ S ₃ ), gallium sulfide (Ga ₂ S ₃ ), strontium sulfide (SrS), and barium sulfide (BaS). Examples of oxides that may be used include zinc oxide (ZnO), yttrium oxide (Y ₂ O ₃ ), and the like. Examples of nitrides that may be used include aluminum nitride (AlN), gallium nitride (GaN), and the like.
Indium nitride (InN) and the like can be used. Furthermore, zinc selenide (ZnSe)
, zinc telluride (ZnTe), etc. can also be used, and calcium gallium sulfide (CaG
Alternatively, the material may be a ternary mixed crystal such as strontium-gallium sulfide (SrGa ₂ S ₄ ), strontium-gallium sulfide (SrGa ₂ S ₄ ), or barium-gallium sulfide (BaGa ₂ S ₄ ).

As the luminescence center of the localized luminescence, manganese (Mn), copper (Cu), samarium (Sm), terbium (Tb), erbium (Er), thulium (Tm), europium (Eu), cerium (Ce), praseodymium (Pr), etc. may be used. Note that halogen elements such as fluorine (F) and chlorine (Cl) may be added as charge compensation.

On the other hand, the first nucleon that forms a donor level serves as the luminescence center of donor-acceptor recombination luminescence.
A light-emitting material containing the first impurity element and a second impurity element forming an acceptor level can be used. The first impurity element can be, for example, fluorine (F), chlorine (Cl), aluminum (Al), or the like. The second impurity element can be, for example, copper (Cu),
Silver (Ag) or the like can be used.

When a light-emitting material of donor-acceptor recombination type light emission is synthesized by a solid phase method, a base material, a first impurity element or a compound containing the first impurity element, and a second impurity element or a compound containing the second impurity element are mixed.
The compounds containing the above impurity elements are weighed out and mixed in a mortar, and then heated and fired in an electric furnace. The above-mentioned base materials can be used as the base material, and the first impurity element or the compound containing the first impurity element can be, for example, fluorine (F), chlorine (Cl), aluminum sulfide (Al ₂ S ₃ ), etc., and the second impurity element or the compound containing the second impurity element can be, for example, copper (Cu), silver (Ag), copper sulfide (Cu ₂ S), silver sulfide (Ag ₂ S), etc. The firing temperature is preferably 700 to 1500°C.
If the temperature is too low, the solid-phase reaction does not proceed, whereas if the temperature is too high, the base material decomposes. Although the firing may be performed in a powder state, it is preferable to perform the firing in a pellet state.

When using a solid-phase reaction, a compound composed of a first impurity element and a second impurity element may be used in combination as an impurity element. In this case, the impurity element is easily diffused,
Since the solid-phase reaction is facilitated, a uniform luminescent material can be obtained. Furthermore, since no extra impurity elements are added, a luminescent material with high purity can be obtained. Examples of compounds composed of the first impurity element and the second impurity element include copper chloride (CuCl), silver chloride (
AgCl) can be used.

The concentration of these impurity elements may be in the range of 0.01 to 10 atom % relative to the base material, and preferably in the range of 0.05 to 5 atom %.

In the case of a thin-film inorganic EL, the electroluminescent layer is a layer containing the above-mentioned luminescent material, and is formed by a resistance heating deposition method,
Vacuum deposition methods such as electron beam deposition (EB deposition) and physical vapor deposition methods such as sputtering (
Chemical vapor deposition (CV) methods such as PVD, metal organic CVD, and hydride transport reduced pressure CVD.
D) and atomic epitaxy (ALE).

108A to 108C show an example of a thin-film inorganic EL element that can be used as a light-emitting element. In FIG. 108A to 108C, the light-emitting element has a first electrode layer 120100
, an electroluminescent layer 120102 , and a second electrode layer 120103 .

The light-emitting elements shown in Fig. 108(B) and Fig. 108(C) have a structure in which an insulating film is provided between the electrode layer and the electroluminescent layer in the light-emitting element shown in Fig. 108(A). The light-emitting element shown in Fig. 108(B) has an insulating film 120104 between the first electrode layer 120100 and the electroluminescent layer 120102, and the light-emitting element shown in Fig. 108(C) has an insulating film 120104 between the first electrode layer 120100 and the electroluminescent layer 120102.
102, an insulating film 120105, a second electrode layer 120103 and an electroluminescent layer 12010
2, an insulating film 120106 is provided between the pair of electrode layers sandwiching the electroluminescent layer. In this manner, the insulating film may be provided only between one of the pair of electrode layers sandwiching the electroluminescent layer, or may be provided between both of them. The insulating film may be a single layer or a laminate having multiple layers.

In FIG. 108B, an insulating film 120104 is formed in contact with the first electrode layer 120100.
However, the order of the insulating film and the electroluminescent layer is reversed, and the second electrode layer 120103
An insulating film 120104 may be provided in contact with the insulating film 120104 .

In the case of a dispersion-type inorganic EL, a particulate light-emitting material is dispersed in a binder to form a film-like electroluminescent layer. The material is processed into particles. If the method for producing the light-emitting material does not provide particles of the desired size, the material may be processed into particles by crushing in a mortar or the like. The binder is,
The binder is a substance that fixes the granular light-emitting material in a dispersed state and maintains the shape of the electroluminescent layer. The light-emitting material is uniformly dispersed and fixed in the electroluminescent layer by the binder.

In the case of a dispersion-type inorganic EL, the electroluminescent layer can be formed by a droplet discharge method, a printing method (screen printing, offset printing, etc.), a coating method such as a spin coat method, a dipping method, a dispenser method, etc., which can selectively form an electroluminescent layer. The film thickness is not particularly limited, but is preferably in the range of 10 to 1000 nm. In an electroluminescent layer containing a luminescent material and a binder, the ratio of the luminescent material is preferably 50 wt % or more and 80 wt % or less.

An example of a dispersion-type inorganic EL element that can be used as a light-emitting element is shown in Fig. 109 (A) to (C). The light-emitting element in Fig. 109 (A) has a laminated structure of a first electrode layer 120200, an electroluminescent layer 120202, and a second electrode layer 120203, and contains a light-emitting material 120201 held by a binder in the electroluminescent layer 120202.

The binder may be an insulating material. As the insulating material, organic and inorganic materials may be used. Alternatively, a mixed material of organic and inorganic materials may be used. As the organic insulating material, a polymer having a relatively high dielectric constant, such as a cyanoethyl cellulose-based resin, polyethylene, polypropylene, a polystyrene-based resin, a silicone resin, an epoxy resin, or vinylidene fluoride may be used. Alternatively, a heat-resistant polymer such as aromatic polyamide or polybenzimidazole, or a siloxane resin may be used. Note that the siloxane resin is a compound having a structure such as Si-O-
It corresponds to a resin containing a Si bond. The skeleton structure of siloxane is composed of bonds between silicon (Si) and oxygen (O). An organic group containing at least hydrogen (e.g., an alkyl group, an aromatic hydrocarbon) is used as a substituent. A fluoro group may be used as a substituent. Alternatively, an organic group containing at least hydrogen and a fluoro group may be used as a substituent. Alternatively,
Resin materials such as vinyl resins such as polyvinyl alcohol and polyvinyl butyral, phenol resins, novolac resins, acrylic resins, melamine resins, urethane resins, and oxazole resins (polybenzoxazole) may also be used.
The dielectric constant can also be adjusted by appropriately mixing fine particles having a high dielectric constant, such as sintered tantalum (aTiO ₃ ) or strontium titanate (SrTiO ₃ ).

The inorganic insulating material contained in the binder is silicon oxide (SiOx), silicon nitride (SiNx
), silicon containing oxygen and nitrogen, aluminum nitride (AlN), aluminum containing oxygen and nitrogen, aluminum oxide containing oxygen and nitrogen (Al ₂ O ₃ ), titanium oxide (TiO ₂ ).
, BaTiO ₃ , SrTiO ₃ , lead titanate (PbTiO ₃ ), potassium niobate (KN
_tantalum oxide ( _Ta2O5 ), _{barium tantalate} ( _BaTa2O6 ), lithium tantalate ( _{LiTaO3 )} , yttrium oxide (Y
_The dielectric constant _of the electroluminescent layer made of the luminescent material and _the binder can be controlled more precisely by adding an inorganic material having a high dielectric constant to the organic material, and the dielectric constant can be increased more precisely by adding an inorganic material having a high dielectric constant to the organic material.

In the manufacturing process, the luminescent material is dispersed in a solution containing a binder. As the solvent for the binder-containing solution, a solvent that dissolves the binder material and can prepare a solution with a viscosity suitable for the method of forming the electroluminescent layer (various wet processes) and the desired film thickness may be appropriately selected. For example, an organic solvent or the like can be used as the solvent. When a siloxane resin is used as the binder, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate (also called PGMEA), 3-methoxy-3-methyl-1-butanol (also called MMB), or the like can be used as the solvent.

The light-emitting elements shown in Fig. 109(B) and Fig. 109(C) have a structure in which an insulating film is provided between the electrode layer and the electroluminescent layer in the light-emitting element shown in Fig. 109(A). The light-emitting element shown in Fig. 109(B) has an insulating film 120204 between the first electrode layer 120200 and the electroluminescent layer 120202, and the light-emitting element shown in Fig. 109(C) has an insulating film 120204 between the first electrode layer 120200 and the electroluminescent layer 120202.
202, an insulating film 120205 is formed between the second electrode layer 120203 and the electroluminescent layer 12020
2, an insulating film 120206 is provided between the pair of electrode layers sandwiching the electroluminescent layer. In this manner, the insulating film may be provided only between one of the pair of electrode layers sandwiching the electroluminescent layer, or may be provided between both of them. The insulating film may be a single layer or a laminate having multiple layers.

In Figure 109 (B), an insulating film 120204 is provided so as to be in contact with the first electrode layer 120200, but the order of the insulating film and the electroluminescent layer may be reversed, and the insulating film 120204 may be provided so as to be in contact with the second electrode layer 120203.

Materials that can be used for insulating films such as insulating film 120104 in FIG. 108 and insulating film 120204 in FIG. 109 preferably have high insulation resistance and are dense films.
Furthermore, it is preferable that the dielectric constant is high. For example, silicon oxide (SiO ₂ ), yttrium oxide (Y ₂ O ₃ ), titanium oxide (TiO ₂ ), aluminum oxide (Al ₂ O ₃ ), hafnium oxide (HfO ₂ ), tantalum oxide (Ta ₂ O ₅ ), barium titanate (BaTi
O ₃ ), strontium titanate (SrTiO ₃ ), lead titanate (PbTiO ₃ ), silicon nitride (Si ₃ N ₄ ), zirconium oxide (ZrO ₂ ), or a mixture or a laminated film of two or more of these can be used. These insulating films can be formed by sputtering, vapor deposition, CVD, or the like. The insulating film may be formed by dispersing particles of these insulating materials in a binder. The binder material may be formed using the same material and method as the binder contained in the electroluminescent layer. The film thickness is not particularly limited, but is preferably 10 to 500 nm.
It is in the range of 1000 nm.

The light-emitting element emits light by applying a voltage between a pair of electrode layers sandwiching an electroluminescent layer, and can be driven by either DC or AC.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 16)
In this embodiment, an example of a display device, particularly a case where optical handling is performed, will be described.

The rear projection display device 130100 shown in Figures 110 (A) and (B) comprises a projector unit 130111, a mirror 130112, and a screen panel 130101.
In addition, the projector unit 130111 may be provided with a speaker 130102 and operation switches 130104.
110, and a mirror 13011 is disposed below the mirror 13011 to project light that projects an image based on a video signal.
The rear projection display device 130100 projects the image onto a screen panel 130101.
The device is configured to display images projected from the rear of the device.

On the other hand, Fig. 111 shows a front projection display device 130200. The front projection display device 130200 comprises a projector unit 130111 and a projection optical system 130201. This projection optical system 130201 is configured to project an image onto a screen or the like disposed in front of it.

A rear projection display device 130100 shown in FIG. 110 and a front projection display device 130100 shown in FIG. 111
The configuration of projector unit 130111 applied to 30200 will be described below.

FIG. 112 shows an example of the configuration of a projector unit 130111. This projector unit 130111 includes a light source unit 130301 and a modulation unit 130304.
The light source unit 130301 includes a light source optical system 1 including lenses.
The light source optical system 130303 includes a light source unit 130303 and a light source lamp 130302. The light source lamp 130302 is housed in a housing so as not to diffuse stray light. The light source lamp 130302 is, for example, a high-pressure mercury lamp or a xenon lamp capable of emitting a large amount of light. The light source optical system 130303 is configured by appropriately providing an optical lens, a film having a polarizing function, a film for adjusting a phase difference, an IR film, etc.
The light emitted from the light source 130304 is arranged so as to be incident on the modulation unit 130304. The modulation unit 130304 includes a plurality of display panels 130308, a color filter, a dichroic mirror 130305, a total reflection mirror 130306, a prism 130309, and a projection optical system 130309.
0310. Light emitted from a light source unit 130301 is separated into a plurality of optical paths by a dichroic mirror 130305.

Each optical path is provided with a color filter that transmits light of a specific wavelength or wavelength band, and a display panel 130308. The display panel 130308 is a transmissive type, and modulates the transmitted light based on a video signal. The light of each color transmitted through the display panel 130308 is reflected by a prism 130
The light is incident on the projector unit 130111 and passes through the projection optical system 130310 to display an image on the screen. A Fresnel lens may be disposed between the mirror and the screen. The projection light projected by the projector unit 130111 and reflected by the mirror is converted by the Fresnel lens into approximately parallel light and projected onto the screen.

The projector unit 130111 shown in FIG. 113 includes a reflective display panel 130407,
A configuration equipped with 130408 and 130409 is shown.

The projector unit 130111 shown in Fig. 113 includes a light source unit 130301 and a modulation unit 130400. The light source unit 130301 may have the same configuration as that shown in Fig. 112. The light from the light source unit 130301 is reflected by a dichroic mirror 130
The light is split into multiple optical paths by the reflection mirror 130403, 130404, 130405, and 130406, and enters the polarizing beam splitters 130404, 130405, and 130406. The polarizing beam splitters 130404, 130405, and 130406 are provided corresponding to the reflective display panels 130407, 130408, and 130409 corresponding to each color. The reflective display panels 130407, 130408, and 130409 modulate the reflected light based on a video signal. The light of each color reflected by the reflective display panels 130407, 130408, and 130409 enters the prism 130309, where it is combined, and projected through the projection optical system 130411.

Of the light emitted from the light source unit 130301, only the light in the red wavelength region is transmitted through the dichroic mirror 130401, and the light in the green and blue wavelength regions is reflected. Furthermore, only the light in the green wavelength region is reflected by the dichroic mirror 130402. The light in the red wavelength region transmitted through the dichroic mirror 130401 is reflected by the total reflection mirror 130403,
The light in the blue wavelength region enters polarizing beam splitter 130404, the light in the green wavelength region enters polarizing beam splitter 130405, and the light in the green wavelength region enters polarizing beam splitter 130406. Polarizing beam splitters 130404, 130405, and 130406 have the function of separating the incident light into P-polarized light and S-polarized light, and have the function of transmitting only P-polarized light. The reflective display panels 130407, 130408, and 130409 polarize the incident light based on a video signal.

Only S-polarized light corresponding to each color is incident on the reflective display panels 130407, 130408, and 130409 corresponding to each color.
130409 may be a liquid crystal panel. In this case, the liquid crystal panel operates in an electric field controlled birefringence mode (ECB). The liquid crystal molecules are aligned perpendicular to the substrate at a certain angle. Therefore, in the reflective display panels 130407, 130408, and 130409, when the pixel is in the off state, the display molecules are aligned so as to reflect the incident light without changing its polarization state. When the pixel is in the on state, the alignment state of the display molecules changes, and the polarization state of the incident light changes.

The projector unit 130111 shown in FIG. 113 can be applied to the rear projection display device 130100 shown in FIG. 110 and the front projection display device 130200 shown in FIG.

The projector unit shown in Fig. 114 shows a single-panel configuration. The projector unit 130111 shown in Fig. 114(A) includes a light source unit 130301, a display panel 13
0507, a projection optical system 130511, and a retardation plate 130504.
The display panel 130507 may be provided with a color filter.

FIG. 114B shows a projector unit 13 that operates in a field sequential manner.
The field sequential method is a method of displaying colors without a color filter by sequentially inputting light of each color, such as red, green, and blue, to a display panel with a time shift. In particular, when combined with a display panel with a high response speed to changes in input signals, it is possible to display high-definition images. In FIG. 114(B), a light source unit 1
Between 30301 and the display panel 130508, there is provided a rotating color filter plate 130505 having a plurality of color filters such as red, green, and blue.

The projector unit 130111 shown in FIG. 114(C) has the following color display method:
This shows the configuration of a color separation method using a macro lens. This method provides a microlens array 130506 on the light input side of a display panel 130509, and realizes color display by illuminating each color of light from a different direction. A projector unit 130111 that employs this method has the advantage that it can effectively utilize the light from the light source unit 130301, since there is little light loss due to color filters.
A projector unit 130111 shown in (C) is equipped with a dichroic mirror 130501, a dichroic mirror 130502, and a dichroic mirror for red light 130503 so as to illuminate a display panel 130509 with light of each color from each direction.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

(Embodiment 17)
In this embodiment, an example of an electronic device will be described.

115 shows a display panel module combining a display panel 900101 and a circuit board 900111. The display panel 900101 has a pixel portion 900102, a scanning line driver circuit 900103, and a signal line driver circuit 900104. For example, a control circuit 900112 and a signal division circuit 900113 are formed on the circuit board 900111. The display panel 900101 and the circuit board 900111 are connected by a connection wiring 900114. An FPC or the like can be used for the connection wiring.

The display panel 900101 is formed by forming a pixel portion 900102 and a part of a peripheral driving circuit (a driving circuit having a low operating frequency among a plurality of driving circuits) integrally on a substrate using transistors, forming a part of a peripheral driving circuit (a driving circuit having a high operating frequency among a plurality of driving circuits) on an IC chip, and mounting the IC chip on the display panel 9001 using COG (Chip On Glass) or the like.
In this way, the area of the circuit board 900111 can be reduced, and a small display device can be obtained. Alternatively, the IC chip can be mounted on a TAB (Tape Auto
The display panel 900101 may be mounted using a bonding technique or a printed circuit board. This makes it possible to reduce the area of the display panel 900101, thereby making it possible to obtain a display device with a small frame size.

For example, in order to reduce power consumption, a pixel portion may be formed on a glass substrate using transistors, all peripheral driving circuits may be formed on an IC chip, and the IC chip may be mounted on a display panel by COG or TAB.

A television receiver can be completed by using the display panel module shown in Fig. 115. Fig. 116 is a block diagram showing the main components of a television receiver. Tuner 9002
01 receives a video signal and an audio signal. The video signal is passed through a video signal amplifier circuit 900202 and
The signal output from the video signal amplifier circuit 900202 is processed by a video signal processing circuit 900203 that converts the signal into a color signal corresponding to each of the colors red, green, and blue, and a control circuit 900212 that converts the video signal into an input specification for a drive circuit.
12 outputs signals to the scanning line side and the signal line side, respectively. In the case of digital driving, a signal division circuit 900213 may be provided on the signal line side to divide an input digital signal into m parts (m is a positive integer) and supply the divided signals.

Of the signals received by the tuner 900201, the audio signal is input to an audio signal amplifier circuit 900205.
The output of the signal is sent to a speaker 900207 via an audio signal processing circuit 900206. A control circuit 900208 receives control information for the receiving station (receiving frequency) and the volume from an input unit 900208.
0209 and sends the signal to the tuner 900201 or the audio signal processing circuit 900206.

Regarding a television receiver incorporating a display panel module of a different form from that of FIG. 116,
In FIG. 117A, a display screen 900301 is housed in a housing 900301.
900302 is formed of a display panel module. In addition, a speaker 900303, an operation switch 900304, an input means 900305, a sensor 900306 (force, displacement, position,
Speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemistry, sound, time, hardness,
The device may be appropriately equipped with a sensor (including a sensor with the function of measuring an electric field, a current, a voltage, a power, a radiation, a flow rate, a humidity, a gradient, a vibration, an odor, or an infrared ray), a microphone 900307, etc.

Fig. 117(B) shows a television receiver that can be carried wirelessly with only the display. A battery and a signal receiver are stored in a housing 900312, and the battery is used to operate a display unit 900313, a speaker unit 900317, and sensors (force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemistry, sound, time, hardness, electric field, current,
The battery drives the 900319 (including the function of measuring voltage, power, radiation, flow rate, humidity, gradient, vibration, odor or infrared rays) and the microphone 900320.
The charger 900310 can be repeatedly charged. The charger 900310 can transmit and receive video signals, and can transmit the video signals to a signal receiver of a display.
The device shown in FIG. 117(B) is controlled by an operation key 900316. Alternatively, the device shown in FIG. 117(B) can be operated by operating the operation key 900316 to operate the charger 90.
117B is capable of sending a signal to the charger 900310 by operating the operation keys 900316, and further capable of controlling communication with other electronic devices by having the other electronic devices receive the signal that the charger 900310 can transmit. In other words, it may be a general-purpose remote control device. Note that input means 900318 and the like may be provided as appropriate. Note that the contents (or even a part of them) described in each figure of this embodiment may be displayed on the display unit 90
This can be applied to 0313.

118A shows a module in which a display panel 900401 and a printed wiring board 900402 are combined. The display panel 900401 includes a pixel portion 900403 having a plurality of pixels, a first scanning line driver circuit 900404, a second scanning line driver circuit 900405, and a second scanning line driver circuit 900406.
05 and a signal line driver circuit 900406 that supplies a video signal to a selected pixel.

The printed wiring board 900402 includes a controller 900407, a central processing unit (CPU
) 900408, memory 900409, power supply circuit 900410, audio processing circuit 90041
1 and a transmission/reception circuit 900412. The printed wiring board 900402 and the display panel 900401 are connected by a flexible wiring board (FPC) 900413. The flexible wiring board (FPC) 900413 may be provided with a storage capacitor, a buffer circuit, etc., to prevent the generation of noise in the power supply voltage or signal, and the increase in the rise time of the signal. The controller 900407, the audio processing circuit 900411, the memory 900409, the central processing unit (CPU) 900408, the power supply circuit 900410, etc.
It is also possible to use a COG (Chip On Glass) method to mount the display panel 900401. By using the COG method, the scale of the printed wiring board 900402 can be reduced.

An interface (I/F) section 900414 provided on the printed wiring board 900402
Various control signals are input and output via the printed wiring board 900402. An antenna port 900415 for transmitting and receiving signals to and from an antenna is provided on the printed wiring board 900402.

Fig. 118(B) shows a block diagram of the module shown in Fig. 118(A). This module includes a VRAM 900416, a DRAM 900417, a flash memory 900418, etc. as the memory 900409. The VRAM 900416 stores image data to be displayed on the panel, the DRAM 900417 stores image data or audio data, and the flash memory stores various programs.

The power supply circuit 900410 supplies power to operate the display panel 900401, the controller 900407, the central processing unit (CPU) 900408, the audio processing circuit 900411, the memory 900409, and the transmission/reception circuit 900412. However, depending on the specifications of the panel, the power supply circuit 900410 may be provided with a current source.

The central processing unit (CPU) 900408 includes a control signal generating circuit 900420 and a decoder 90
900421, a register 900422, an arithmetic circuit 900423, a RAM 900424, and an interface (I/F) section 900419 for a central processing unit (CPU) 900408.
The various signals input to 900408 are temporarily stored in a register 900422, and then input to an arithmetic circuit 900423, a decoder 900421, etc. The arithmetic circuit 900423 performs an operation based on the input signal and specifies the location to send various commands.
The signal input to the control signal generating circuit 900421 is decoded and input to the control signal generating circuit 900420. The control signal generating circuit 900420 generates a signal including various commands based on the input signal, and transmits the signal to a specified location in the arithmetic circuit 900423, specifically, the memory 900409,
The signal is sent to the transmission/reception circuit 900412, the audio processing circuit 900411, the controller 900407, etc.

The memory 900409, the transmission/reception circuit 900412, the audio processing circuit 900411, and the controller 900407 operate according to the instructions they receive. The operations will be briefly described below.

The signal input from the input means 900425 is input to an interface (I/F) section 90041.
A central processing unit (CPU) 9004 mounted on a printed wiring board 900402 via a
08. The control signal generating circuit 900420 converts the image data stored in the VRAM 900416 into a predetermined format in accordance with a signal sent from an input means 900425 such as a pointing device or a keyboard, and sends it to the controller 900407.

The controller 900407 controls the central processing unit (CPU) 9004 according to the panel specifications.
08, a signal including image data is subjected to data processing, and a display panel 90040
The controller 900407 controls the Hs
It generates a sync signal, a Vsync signal, a clock signal CLK, an AC voltage (AC Cont), and a switching signal L/R, and supplies them to the display panel 900401.

In the transmission/reception circuit 900412, signals transmitted and received as radio waves by the antenna 900428 are processed. Specifically, the circuit includes an isolator, a bandpass filter, a VCO (Volt
age Controlled Oscillator), LPF (Low Pass
The transmission/reception circuit 90 may include high-frequency circuits such as a filter, a coupler, and a balun.
Among the signals transmitted and received in the 0412, a signal including voice information is transmitted to the central processing unit (CPU
) 900408, the signal is sent to the audio processing circuit 900411 in accordance with an instruction from the audio processing circuit 900411.

A signal including voice information transmitted in accordance with a command from the central processing unit (CPU) 900408 is demodulated into a voice signal in the voice processing circuit 900411 and transmitted to the speaker 900427. A voice signal transmitted from the microphone 900426 is modulated in the voice processing circuit 900411 and transmitted to the transmission/reception circuit 900427 in accordance with a command from the central processing unit (CPU) 900408.
Sent to 00412.

Controller 900407, central processing unit (CPU) 900408, power supply circuit 90041
0, an audio processing circuit 900411, and a memory 900409 can be implemented as a package according to this embodiment.

Of course, this embodiment is not limited to television receivers, but can be applied to a variety of uses, particularly as a large-area display medium, such as personal computer monitors, information display boards at railway stations or airports, and advertising display boards on the street.

Next, we will explain an example of the configuration of a mobile phone with reference to Figure 119.

The display panel 900501 is detachably assembled in the housing 900530. The shape or dimensions of the housing 900530 can be changed as appropriate according to the size of the display panel 900501. The housing 900530 to which the display panel 900501 is fixed is fitted into a printed circuit board 900531 and assembled as a module.

The display panel 900501 is connected to a printed circuit board 900531 via an FPC 900513. The printed circuit board 900531 is provided with a speaker 900532, a microphone 900
533, a transmission/reception circuit 900, 534, a signal processing circuit 900 including a CPU, a controller, etc.
535 and a sensor 900541 (including a function of measuring force, displacement, position, speed, acceleration, angular velocity, number of rotations, distance, light, liquid, magnetism, temperature, chemistry, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays) are formed. Such a module is combined with an input means 900536 and a battery 900537 and housed in a housing 900539. The pixel portion of the display panel 900501 is housed in the housing 900539.
The sensor is positioned so that it can be seen through an opening window formed in the sensor.

The display panel 900501 is configured such that a pixel portion and some of the peripheral driving circuits (a driving circuit having a low operating frequency among a plurality of driving circuits) are integrally formed on a substrate using transistors, and some of the peripheral driving circuits (a driving circuit having a high operating frequency among a plurality of driving circuits) are formed on an IC chip, and the IC
The chip may be mounted on the display panel 900501 by COG (Chip On Glass). Alternatively, the IC chip may be connected to the glass substrate by TAB (Tape Automated Bonding) or a printed circuit board. With such a configuration, the power consumption of the display device can be reduced, and the usage time of the mobile phone on a single charge can be extended. The cost of the mobile phone can be reduced.

The mobile phone shown in FIG. 119 has a function to display various information (still images, videos, text images, etc.). It has a function to display a calendar, date, time, etc. on the display unit. It has a function to operate or edit the information displayed on the display unit. Various software (programs)
It has a function to control processing by. It has a wireless communication function. It has a function to make calls to other mobile phones, landlines, or voice communication devices using the wireless communication function. It has a function to connect to various computer networks using the wireless communication function. It has a function to send or receive various data using the wireless communication function. It has a function to operate a vibrator in response to an incoming call, reception of data, or an alarm. It has a function to generate a sound in response to an incoming call, reception of data, or an alarm. Note that the functions of the mobile phone shown in FIG. 119 are not limited to these, and it may have a variety of functions.

The mobile phone shown in FIG. 120 includes operation switches 900604 and a microphone 90060
5, etc., and a main body (B) 900602 equipped with a display panel (A) 900608, a display panel (B) 900609, a speaker 900606, a sensor 900611 (including a function for measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemistry, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared), an input means 900612, etc.
The display panel (A) 900608 and the display panel (B) 900609 are connected to each other so as to be able to open and close by a hinge 900610. The display panel (A) 900608 and the display panel (B) 900609 are connected to the main body (B) 900602 together with the circuit board 900607.
The display panel (A) 900608 and the display panel (
B) The pixel portion of 900609 is arranged so as to be visible through an opening window formed in the housing 900603.

The display panel (A) 900608 and the display panel (B) 900609 are the same as those of the mobile phone 90.
The number of pixels and other specifications can be set appropriately depending on the function of the display panel 0600. For example, the display panel (A) 900608 can be used as a main screen, and the display panel (B) 900609 can be used as a sub-screen.

The mobile phone according to this embodiment can be transformed into various forms depending on its functions or uses. For example, an imaging element may be incorporated in the hinge 900610 to make it into a mobile phone with a camera. The above-mentioned effects can be obtained even if the operation switches 900604, the display panel (A) 900608, and the display panel (B) 900609 are housed in a single housing. The same effects can be obtained even if the configuration of this embodiment is applied to an information display terminal equipped with multiple display units.

The mobile phone shown in FIG. 120 has a function to display various information (still images, videos, text images, etc.). It has a function to display a calendar, date, time, etc. on the display unit. It has a function to operate or edit the information displayed on the display unit. Various software (programs)
It has a function of controlling processing by. It has a wireless communication function. It has a function of making calls to other mobile phones, landlines, or voice communication devices using the wireless communication function. It has a function of connecting to various computer networks using the wireless communication function. It has a function of sending or receiving various data using the wireless communication function. It has a function of activating a vibrator in response to an incoming call, reception of data, or an alarm. It has a function of generating a sound in response to an incoming call, reception of data, or an alarm. Note that the functions of the mobile phone shown in FIG. 120 are not limited to these, and it may have a variety of functions.

The contents (or even a part of them) described in each drawing of this embodiment can be applied to various electronic devices. Specifically, it can be applied to the display unit of an electronic device. Such electronic devices include video cameras, digital cameras, goggle-type displays, navigation systems, audio playback devices (car audio, audio components, etc.), computers, game devices, and portable information terminals (mobile computers, mobile phones, portable game machines, e-books, etc.).
, an image reproducing device equipped with a recording medium (specifically, a Digital Versatile Digital
isc (a device equipped with a display capable of playing recording media such as DVDs and displaying the images).

FIG. 121(A) shows a display, which includes a housing 900711, a support base 900712, a display unit 900713, an input unit 900714, and a sensor (including a function for measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemistry, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays) 9
00715, microphone 900716, speaker 900717, operation key 90071
121A includes a display unit 900, 901, 902, 903, 904, 905, 910, 911, 912, 913, 914, 915, 916, 917, 918, 919, 920, 921, 922, 923, 924, 925, 926, 927, 928, 929, 930, 931, 932, 933, 934, 935, 936, 937, 938, 939, 940, 941, 942, 943, 944, 945, 946, 947, 948, 949, 950, 951, 952,
The functions of the display shown in 21(A) are not limited to those described above, and the display may have a variety of functions.

FIG. 121B shows a camera, which includes a main body 900731, a display unit 900732, and an image receiving unit 900
733, operation keys 900734, external connection port 900735, shutter 900736
, input means 900737, sensor 900738 (including functions for measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemistry, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor or infrared rays),
The camera shown in FIG. 121B includes a microphone 900739, a speaker 900740, an LED lamp 900741, etc. The camera shown in FIG. 121B has a function of taking still images. It has a function of taking videos. It has a function of automatically correcting the taken images (still images, videos). It has a function of saving the taken images in a recording medium (external or built into the digital camera). It has a function of displaying the taken images on a display unit. Note that the functions of the camera shown in FIG. 121B are not limited to these, and it can have various functions.

FIG. 121C shows a computer, which includes a main body 900751, a housing 900752, and a display unit 9
00753, keyboard 900754, external connection port 900755, pointing device 900756, input means 900757, sensor (force, displacement, position, velocity, acceleration,
121C includes a display unit 900758 (including a function for measuring angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemistry, voice, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays), a microphone 900759, a speaker 900760, an LED lamp 900761, a reader/writer 900762, etc. The computer shown in FIG. 121C has a function for displaying various information (still images, videos, text images, etc.) on the display unit. It has a function for controlling processing by various software (programs). It has a communication function such as wireless communication or wired communication. It has a function for connecting to various computer networks using the communication function. It has a function for transmitting or receiving various data using the communication function. Note that the functions of the computer shown in FIG. 121C are not limited to these, and it can have various functions.

FIG. 128A shows a mobile computer, which includes a main body 901411 and a display unit 901412.
, a switch 901413, an operation key 901414, an infrared port 901415, an input means 901416, a sensor (including a function for measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemistry, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared) 901417, a microphone 901418, a speaker 901419, an LED lamp 901420, etc.
The mobile computer shown in FIG. 128(A) has a function of displaying various information (still images, videos, text images, etc.) on the display unit. The display unit has a touch panel function. The display unit has a function of displaying a calendar, date, time, etc. The display unit has a function of controlling processing using various software (programs). The mobile computer has a wireless communication function. The mobile computer has a function of connecting to various computer networks using the wireless communication function. The mobile computer has a function of transmitting or receiving various data using the wireless communication function. Note that the functions of the mobile computer shown in FIG. 128(A) are not limited to these, and the mobile computer can have a variety of functions.

FIG. 128(B) shows a portable image reproducing device (for example, a DVD reproducing device) equipped with a recording medium.
A main body 901431, a housing 901432, a display unit A 901433, and a display unit B 901
434, a recording medium (DVD, etc.) reading unit 901435, operation keys 901436, a speaker unit 901437, input means 901438, a sensor 901439 (including a function for measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemistry, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared), a microphone 901440, an LED lamp 901441, etc. The display unit A 901433 mainly displays image information, and the display unit B 901434 mainly displays text information.

FIG. 128C shows a goggle-type display, which includes a main body 901451 and a display unit 90145.
2, earphone 901453, support part 901454, input means 901455, sensor (force,
Displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemistry, sound,
128(C) includes a display unit 901456 (including a function for measuring time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays), a microphone 901457, and a speaker 901458. The goggle-type display shown in FIG. 128(C) has a function for displaying images (still images, videos, text images, etc.) acquired from the outside on the display unit.
The functions of the goggle-type display shown in FIG. 128C are not limited to those described above, and the display can have a variety of functions.

FIG. 129(A) shows a portable game machine, which includes a housing 901511, a display unit 901512, a speaker unit 901513, operation keys 901514, a storage medium insertion unit 901515, and an input unit 90
1516, a sensor (including a function for measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemistry, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared) 901517, a microphone 901518, an LED lamp 901519, etc. The portable gaming machine shown in FIG. 129(A) has a function for reading out a program or data recorded in a recording medium and displaying it on a display unit. It has a function for sharing information by wireless communication with other portable gaming machines. Note that the functions of the portable gaming machine shown in FIG. 129(A) are not limited to these, and it can have various functions.

FIG. 129B shows a digital camera with a television receiving function, which includes a main body 901531, a display section 901532, operation keys 901533, a speaker 901534, and a shutter 901535.
, an image receiving unit 901536, an antenna 901537, an input means 901538, a sensor (including a function for measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemistry, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared) 901539, a microphone 901540, an LED lamp 901541, etc. The digital camera with a television receiver shown in FIG. 129(B) has a function for taking still images. It has a function for taking videos. It has a function for automatically correcting the taken image. It has a function for acquiring various information from an antenna. It has a function for saving the taken image or the information acquired from the antenna. It has a function for displaying the taken image or the information acquired from the antenna on the display unit. Note that the functions of the digital camera with a television receiver shown in FIG. 121(H) are not limited to these, and can have various functions.

FIG. 130 shows a portable gaming machine, which includes a housing 901611, a first display unit 901612, a second display unit 901613, a speaker unit 901614, operation keys 901615, a recording medium insertion unit 90
1616, Input means 901617, Sensor (force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetic, temperature, chemical, sound, time, hardness, electric field, current, voltage, power,
(including functions for measuring radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays) 901
130 includes a display 901-618, a microphone 901-619, and an LED lamp 901-620. The portable gaming machine shown in Fig. 130 has a function of reading out a program or data recorded on a recording medium and displaying it on a display unit. It has a function of communicating wirelessly with other portable gaming machines to share information. Note that the functions of the portable gaming machine shown in Fig. 130 are not limited to these, and the machine may have various functions.

As shown in Fig. 121 (A) to (C), Fig. 128 (A) to (C), Fig. 129 (A) to (C), and Fig. 130, electronic devices are characterized by having a display portion for displaying some information. The electronic devices can be provided with a display portion having a wide viewing angle.

Next, we will explain application examples of semiconductor devices.

An example in which a semiconductor device is integrated with a building is shown in Fig. 122. Fig. 122 includes a housing 900810, a display portion 900811, a remote control device 900812 which is an operation portion, a speaker portion 900813, etc. The semiconductor device is integrated with a building as a wall-mounted type, and can be installed without requiring a large installation space.

FIG. 123 shows another example in which a semiconductor device is provided inside a building as an integral part of the building.
The display panel 900901 is attached integrally to the unit bath 900902, allowing bathers to view the display panel 900901. The display panel 900901 has a function of displaying information when operated by bathers. It also has a function of being usable as advertising or entertainment means.

The semiconductor device may be used not only on the side wall of the unit bath 900902 shown in FIG.
The display panel 900/901 may be installed in various locations. For example, the display panel 900/901 may be integrated into a part of a mirror surface or into the bathtub itself. In this case, the shape of the display panel 900/901 may be adapted to the shape of the mirror surface or the bathtub.

124 shows another example in which a semiconductor device is provided integrally with a building. A display panel 901002 is attached to a pillar 901001 while being curved to fit the curved surface of the pillar 901001.
In this description, the columnar body 901001 is assumed to be a utility pole.

The display panel 901002 shown in FIG. 124 is positioned higher than the human eye position.
By installing the display panel 901002 on a structure that stands repeatedly outdoors, such as a utility pole, it is possible to advertise to an unspecified number of viewers.
Since the display panel 901002 can easily display the same image and instantly switch images by external control, it is expected to be highly effective in displaying information and advertising. By providing the display panel 901002 with a self-luminous display element, it can be said to be useful as a display medium with high visibility even at night. By installing it on a utility pole, it is easy to secure a means of supplying power to the display panel 901002. In the event of an emergency such as a disaster, it can also be a means of quickly conveying accurate information to victims.

As the display panel 901002, for example, a display panel in which switching elements such as organic transistors are provided on a film-like substrate and images are displayed by driving the display elements can be used.

In this embodiment, a wall, a pillar, and a unit bath are taken as examples of structures, but this embodiment is not limited to these, and the semiconductor device can be installed in various structures.

Next, we will show an example in which a semiconductor device is integrated with a moving object.

125 is a diagram showing an example in which a semiconductor device is integrated with an automobile. A display panel 901102 is attached integrally to a body 901101 of the automobile, and can display on demand the operation of the automobile body or information input from inside or outside the automobile. Note that a navigation function may be provided.

The semiconductor device can be installed in various places, not just the vehicle body 901101 shown in Fig. 125. For example, it may be integrated with a glass window, a door, a handle, a shift lever, a seat, a rearview mirror, etc. In this case, the shape of the display panel 901102 may be adapted to the shape of the object on which it is installed.

Figure 126 shows an example of a semiconductor device being integrated into a train car.

Fig. 126(a) is a diagram showing an example in which a display panel 901202 is provided on the glass of a door 901201 of a train car. Compared to conventional paper advertisements, this has the advantage of not requiring labor costs required for switching advertisements. The display panel 901202 can instantly switch images displayed on the display unit in response to an external signal, so that, for example, the image on the display panel can be switched according to the time period when the customer demographics of passengers getting on and off the train change, and more effective advertising effects can be expected.

FIG. 126(b) shows the glass of the train car door 901201 and the glass window 901203.
901202 and a ceiling 901204.
In this way, the semiconductor device can be easily installed in places where installation was previously difficult, and therefore effective advertising effects can be obtained. The semiconductor device can instantly switch images displayed on the display unit in response to an external signal, which reduces the cost and time required for switching advertisements, and enables more flexible advertising and information transmission.

The semiconductor device can be installed in various places, not just the door 901201, the glass window 901203, and the ceiling 901204 shown in Fig. 126. For example, it may be integrated with a hanging strap, a seat, a handrail, a floor, etc. In this case, the shape of the display panel 901202 may be adapted to the shape of the object on which it is installed.

FIG. 127 is a diagram showing an example in which a semiconductor device is integrated with a passenger airplane.

FIG. 127(a) shows a display panel 90130 mounted on a ceiling 901301 above the seats of a passenger airplane.
9 is a diagram showing the shape of the display panel 901302 when it is in use.
It is attached to the ceiling 901301 via a hinge section 901303, and passengers can view the display panel 901302 by expanding and contracting the hinge section 901303. The display panel 901302 has a function of displaying information when operated by passengers, and can be used as advertising or entertainment. As shown in FIG. 127(b), the hinge section can be folded and stored in the ceiling 901301, ensuring safety during takeoff and landing.
In an emergency, the display elements of the display panel can be turned on to be usable as a means of transmitting information and as an emergency exit light.

The semiconductor device can be installed in various places, not just the ceiling 901301 shown in Fig. 127. For example, it may be integrated with a seat, a seat table, an armrest, a window, etc. A large display panel that can be viewed by many people at the same time may be installed on the wall of the aircraft. In this case, the shape of the display panel 901302 may be adapted to the shape of the object on which it is installed.

In this embodiment, the moving body is exemplified by a train car body, an automobile body, and an airplane body, but is not limited thereto.
The semiconductor device can be installed in various things such as trains (including monorails, railways, etc.), ships, etc. Since the semiconductor device can instantly switch the display on the display panel inside the moving body by an external signal, by installing the semiconductor device in the moving body, the moving body can be used for purposes such as an advertising display board targeting an unspecified number of customers, an information display board in the event of a disaster, etc.

In this embodiment, various figures have been used to describe the present invention.
(or a part of) the contents described in another figure (or a part of)
Furthermore, in the figures described above, by combining each part with another part, more figures can be constructed.

Similarly, the contents (or even a part of them) described in each figure of this embodiment can be freely applied, combined, or replaced with the contents (or even a part of them) described in the figures of other embodiments. Furthermore, by combining each part of the figures of this embodiment with parts of other embodiments, even more figures can be configured.

In addition, this embodiment is an example of a case where the contents (or a part thereof) described in the other embodiments are embodied, a slightly modified example, a partially changed example, an improved example,
The following describes an example of a detailed description, an example of an application, an example of a related part, etc. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or substituted for this embodiment.

100 Pixel 101 Switch 102 Switch 103 Liquid crystal element 103 Potential V
104 Liquid crystal element 105 Liquid crystal element 106 Capacitor 107 Capacitor 108 Wiring 109 Wiring 110 Wiring 111 Common electrode 150 Pixel 151 Switch 152 Switch 153 Liquid crystal element 154 Liquid crystal element 155 Liquid crystal element 156 Capacitor 157 Capacitor 158 Wiring 159 Wiring 160 Wiring 161 Capacitor 200 Pixel 201 Switch 202 Switch 203 Switch 203 Transistor 204 Liquid crystal element 205 Liquid crystal element 206 Liquid crystal element 207 Capacitor 208 Capacitor 209 Wiring 210 Wiring 211 Wiring 253 Transistor 260 Wiring 261 Wiring 262 Wiring 301 Switch 302 Switch 303 Transistor 309 Wiring 310 Wiring 313 Wiring 353 Transistor 356 Liquid crystal element 359 Capacitor 364 Wiring 400 Pixel 401 Switch 402 Switch 403 Liquid crystal element 404 Liquid crystal element 405 Liquid crystal element 406 Capacitor 407 Capacitor 408 Capacitor 409 Capacitor 410 Wiring 411 Wiring 412 Wiring 413 Wiring 414 Wiring 415 Wiring 416 Common electrode 417 Capacitor 450 Pixel 451 Switch 452 Switch 453 Liquid crystal element 454 Liquid crystal element 455 Liquid crystal element 456 Capacitor 457 Capacitor 458 Wiring 459 Wiring 460 Wiring 461 Common electrode 463 Capacitor line 465 Capacitor line 500 Pixel 501 Switch 502 Switch 503 Liquid crystal element 504 Liquid crystal element 505 Liquid crystal element 506 Liquid crystal element 507 Capacitor 508 Capacitor 509 Capacitor 510 Wiring 511 Wiring 512 Wiring 550 Pixel 551 Switch 552 Switch 553 Switch 554 Liquid crystal element 555 Liquid crystal element 556 Liquid crystal element 557 Liquid crystal element 558 Capacitor 559 Capacitor 560 Wiring 561 Wiring 562 Wiring 563 Wiring 565 Capacitor 566 Capacitor 572 Capacitor 584 Capacitor 600 Pixel 601 Switch 602 Switch 603 Liquid crystal element 604 Liquid crystal element 605 Liquid crystal element 606 Voltage dividing element 607 Voltage dividing element 608 Wiring 609 Wiring 610 Wiring 650 Pixel 651 Switch 652 Switch 653 Liquid crystal element 654 Liquid crystal element 655 Liquid crystal element 656 Voltage dividing element 657 Voltage dividing element 658 Switch 659 Switch 660 Wiring 661 Wiring 662 Wiring 700 Pixel 701 Switch 702 Switch 703 Liquid crystal element 704 Liquid crystal element 705 Liquid crystal element 706 Transistor 707 Transistor 708 Wiring 709 Wiring 710 Wiring 750 Pixel 751 Switch 752 Switch 753 Liquid crystal element 754 Liquid crystal element 755 Liquid crystal element 756 Transistor 757 Transistor 758 Wiring 759 Wiring 760 Wiring 761 Wiring 762 Capacitor 763 Capacitor 764 Capacitor 800 Pixel 801 Switch 802 Switch 803 Transistor 803 Liquid crystal element 804 Transistor 804 Liquid crystal element 805 Liquid crystal element 806 Liquid crystal element 807 Liquid crystal element 808 Wiring 809 Wiring 810 Wiring 811 Wiring 850 Pixel 851 Switch 852 Switch 853 Liquid crystal element 854 Liquid crystal element 855 Liquid crystal element 856 Transistor 857 Transistor 858 Wiring 859 Wiring 860 Wiring 861 Capacitor 900 Pixel 901 Switch 902 Switch 903 Liquid crystal element 904 Liquid crystal element 905 Liquid crystal element 906 Liquid crystal element 907 Transistor 908 Transistor 909 Transistor 910 Wiring 911 Wiring 912 Wiring 101N Switch 101P Switch 102N Switch 102P Switch 105a Liquid crystal element 105b Liquid crystal element 151N Switch 152N Switch 1911 Signal line driver circuit 1912 Scanning line driver circuit 1913 Pixel portion 1914 Pixel 201N Switch 202N Switch 211A Wiring 251N Switch 252N Switch 301N Switch 302N Switch 401N Switch 402N Switch 451N Switch 452N Switch 501N Switch 502N Switch 551N Switch 552N Switch 601N Switch 602N Switch 651N Switch 652N Switch 701N Switch 702N Switch 751N Switch 752N Switch 801N Switch 802N Switch 851N Switch 852N Switch 901N Switch 902N Switch 107320 FPC
107321 IC chip 170100 Substrate 170101 Pixel portion 170102 Pixel 170103 Scanning line side input terminal 170104 Signal line side input terminal 170105 Scanning line driving circuit 170106 Signal line driving circuit 170200 FPC
170201 IC chip 170300 Substrate 170301 Pixel section 170303 Signal line driver circuit 170310 Substrate 170320 FPC
170321 Sealing material 170401 IC chip 170302a Scanning line driver circuit 170302b Scanning line driver circuit 170501a IC chip 170501b IC chip 180100 Display device 180101 Pixel portion 180102 Pixel 180103 Signal line driver circuit 180104 Scanning line driver circuit 180701 Image 180702 Image 180703 Image 180704 Image 180705 Image 180711 Image 180712 Image 180713 Image 180714 Image 180715 Image 180716 Image 180717 Image 180721 Image 180722 Image 180723 Image 180724 Image 180725 Image 180801 Image 180802 Image 180803 Image 180804 Region 180805 Region 180806 Region 180811 Image 180812 Image 180813 Image 180814 Region 180815 Region 180816 Region 180821 Image 180822 Image 180823 Image 180824 Region 180825 Region 180826 Region 180831 Image 180832 Image 180833 Image 180834 Region 180835 Region 180836 Region 180841 Region 180842 Point 180901 Image 180902 Image 180903 Image 180904 Region 180905 Region 180906 Region 180907 Range 180908 Range 180909 Vector 180910 Displacement vector 180911 Image 180912 Image 180913 Image 180914 Image 180915 Region 180916 Region 180917 Region 180918 Region 180919 Range 180920 Range 180921 Motion vector 180922 Displacement vector 180923 Displacement vector 181000 External image signal 181001 Horizontal sync signal 181002 Vertical sync signal 181003 Image signal 181004 Source start pulse 181005 Source clock 181006 Gate start pulse 181007 Gate clock 181008 Frequency control signal 181011 Control circuit 181012 Source driver 181013 Gate driver 181014 Display area 181015 Image processing circuit 181016 Timing generation circuit 181020 Detection circuit 181021 First memory 181022 Second memory 181023 Third memory 181023 Image signal 181024 Brightness control circuit 181025 High speed processing circuit 181026 Memory 20101 Backlight unit 20102 Diffusion plate 20103 Light guide plate 20104 Reflection plate 20105 Lamp reflector 20106 Light source 20107 Liquid crystal panel 20201 Backlight unit 20202 Lamp reflector 20203 Cold cathode fluorescent tube 20211 Backlight unit 20212 Lamp reflector 20213 Light emitting diode (LED)
20213W Light emitting diode 20221 Backlight unit 20222 Lamp reflector 20223 Light emitting diode (LED)
20224 Light Emitting Diode (LED)
20225 Light Emitting Diode (LED)
20231 Backlight unit 20232 Lamp reflector 20233 Light emitting diode (LED)
20234 Light Emitting Diode (LED)
20235 Light Emitting Diode (LED)
20300 Polarizing film 20301 Protective film 20302 Substrate film 20303 PVA polarizing film 20304 Substrate film 20305 Adhesive layer 20306 Release film 20401 Video signal 20402 Control circuit 20403 Signal line driver circuit 20404 Scanning line driver circuit 20405 Pixel section 20406 Illumination means 20407 Power supply 20408 Driver circuit section 20410 Scanning line 20412 Signal line 20431 Shift register 20432 Latch 20433 Latch 20434 Level shifter 20435 Buffer 20441 Shift register 20442 Level shifter 20443 Buffer 20500 Backlight unit 20501 Diffusion plate 20502 Light shielding plate 20503 Lamp reflector 20504 Light source 20505 Liquid crystal panel 20510 Backlight unit 20511 Diffusion plate 20512 Light shielding plate 20513 Lamp reflector 20514 Light source 20515 Liquid crystal panel 20514a Light source (R)
20514b Light source (G)
20514c Light source (B)
40100 Pixel 40101 Transistor 40102 Liquid crystal element 40103 Capacitive element 40104 Wiring 40105 Wiring 40106 Wiring 40107 Counter electrode 40110 Pixel 40111 Transistor 40112 Liquid crystal element 40113 Capacitive element 40114 Wiring 40115 Wiring 40116 Wiring 40200 Pixel (Pixel 40200 Pixel 40201 Transistor 40202 Liquid crystal element 40203 Capacitive element 40204 Wiring 40205 Wiring 40206 Wiring 40207 Counter electrode 40210 Pixel 40211 Transistor 40212 Liquid crystal element 40213 Capacitive element 40214 Wiring 40215 Wiring 40216 Wiring 40217 Counter electrode 40300 Subpixel 40301 Transistor 40302 Liquid crystal element 40303 Capacitive element 40304 Wiring 40305 Wiring 40306 Wiring 40307 Counter electrode 40310 Subpixel 40311 Transistor 40312 Liquid crystal element 40313 Capacitive element 40315 Wiring 40316 Wiring 40317 Counter electrode 40320 Pixel 50100 Liquid crystal layer 50101 Substrate 50102 Substrate 50103 Polarizing plate 50104 Polarizing plate 50105 Electrode 50106 Electrode 50200 Liquid crystal layer 50201 Substrate 50202 Substrate 50203 Polarizing plate 50204 Polarizing plate 50205 Electrode 50206 Electrode 50210 Liquid crystal layer 50211 Substrate 50212 Substrate 50213 Polarizing plate 50214 Polarizing plate 50215 Electrode 50216 Electrode 50300 Liquid crystal layer 50301 Substrate 50302 Substrate 50303 Polarizing plate 50304 Polarizing plate 50305 Electrode 50306 Electrode 50310 Liquid crystal layer 50311 Substrate 50312 Substrate 50313 Polarizing plate 50314 Polarizing plate 50315 Electrode 50316 Electrode 50400 Liquid crystal layer 50401 Substrate 50402 Substrate 50403 Polarizing plate 50404 Polarizing plate 50405 Electrode 50406 Electrode 50410 Liquid crystal layer 50411 Substrate 50412 Substrate 50413 Polarizing plate 50414 Polarizing plate 50415 Electrode 50416 Electrode 50417 Insulating film 50501 Pixel electrode 50503, protrusion 50601, pixel electrode 50602, pixel electrode 50611, pixel electrode 50612, pixel electrode 50631, pixel electrode 50632, pixel electrode 50641, pixel electrode 50642, pixel electrode 50701, pixel electrode 50702, pixel electrode 50711, pixel electrode 50712, pixel electrode 50731, pixel electrode 50732, pixel electrode 50741, pixel electrode 50742, pixel electrode 502117, protrusion 502118, protrusion 10101, substrate 10102, insulating film 10103, conductive layer 10104, insulating film 10105, semiconductor layer 10106, semiconductor layer 10107, conductive layer 10108, insulating film 10109, conductive layer 10110, alignment film 10112, alignment film 10113 Conductive layer 10114 Light-shielding film 10115 Color filter 10116 Substrate 10117 Spacer 10118 Liquid crystal molecule 10201 Substrate 10202 Insulating film 10203 Conductive layer 10204 Insulating film 10205 Semiconductor layer 10206 Semiconductor layer 10207 Conductive layer 10208 Insulating film 10209 Conductive layer 10210 Alignment film 10212 Alignment film 10213 Conductive layer 10214 Light-shielding film 10215 Color filter 10216 Substrate 10217 Spacer 10218 Liquid crystal molecule 10219 Alignment control protrusion 10231 Substrate 10232 Insulating film 10233 Conductive layer 10234 Insulating film 10235 Semiconductor layer 10236 Semiconductor layer 10237 Conductive layer 10238 Insulating film 10239 Conductive layer 10240 Alignment film 10242 Alignment film 10243 Conductive layer 10244 Light-shielding film 10245 Color filter 10246 Substrate 10247 Spacer 10248 Liquid crystal molecule 10249 Part 10301 Substrate 10302 Insulating film 10303 Conductive layer 10304 Insulating film 10305 Semiconductor layer 10306 Semiconductor layer 10307 Conductive layer 10308 Insulating film 10309 Conductive layer 10310 Alignment film 10312 Alignment film 10314 Light-shielding film 10315 Color filter 10316 Substrate 10317 Spacer 10318 Liquid crystal molecule 10331 Substrate 10332 Insulating film 10333 Conductive layer 10334 Insulating film 10335 Semiconductor layer 10336 Semiconductor layer 10337 Conductive layer 10338 Insulating film 10339 Conductive layer 10340 Alignment film 10342 Alignment film 10343 Conductive layer 10344 Light-shielding film 10345 Color filter 10346 Substrate 10347 Spacer 10348 Liquid crystal molecule 10349 Insulating film 10401 Scanning line 10402 Video signal line 10403 Capacitor line 10404 Transistor 10405 Pixel electrode 10406 Pixel capacitor 10501 Scanning line 10502 Video signal line 10503 Capacitor line 10504 Transistor 10505 Pixel electrode 10506 Pixel capacitor 10507 Alignment control protrusion 10511 Scanning line 10512 Video signal line 10513 Capacitor line 10514 Transistor 10515 Pixel electrode 10516 Pixel capacitor 10517 Part 10601 Scanning line 10602 Video signal line 10603 Common electrode 10604 Transistor 10605 Pixel electrode 10611 Scanning line 10612 Video signal line 10613 Common electrode 10614 Transistor 10615 Pixel electrode 106013 Common electrode 70101 Substrate 70102 Orientation film 70103 Roller 70104 Rubbing roller 70105 Sealing material 70106 Spacer 70107 Substrate 70108 Orientation film 70109 Liquid crystal 70110 Resin 70113 Liquid crystal injection port 70301 Substrate 70302 Orientation film 70303 Roller 70304 Rubbing roller 70305 Sealing material 70306 Spacer 70307 Substrate 70308 Alignment film 70309 Liquid crystal 80300 Pixel 80301 Switching transistor 80302 Driving transistor 80303 Capacitive element 80304 Light-emitting element 80305 Signal line 80306 Scanning line 80307 Power supply line 80308 Common electrode 80309 Rectifying element 80400 Pixel 80401 Switching transistor 80402 Driving transistor 80403 Capacitive element 80404 Light-emitting element 80405 Signal line 80406 Scanning line 80407 Power supply line 80408 Common electrode 80409 Rectifying element 80410 Scanning line 80500 Pixel 80501 Switching transistor 80502 Driving transistor 80503 Capacitive element 80504 Light-emitting element 80505 Signal line 80506 Scanning line 80507 Power supply line 80508 Common electrode 80509 Erasing transistor 80510 Scanning line 80600 Driving transistor 80601 Switch 80602 Switch 80603 Switch 80604 Capacitor 80605 Capacitor 80611 Signal line 80612 Power supply line 80613 Scanning line 80614 Scanning line 80620 Light-emitting element 80621 Common electrode 80700 Driving transistor 80701 Switch 80702 Switch 80703 Switch 80704 Capacitor 80711 Signal line 80712 Power supply line 80713 Scanning line 80714 Scanning line 80730 Light-emitting element 80731 Common electrode 80734 Scanning line 70101 Substrate 70102 Alignment film 70103 Roller 70104 Rubbing roller 70105 Seal material 70106 Spacer 70107 Substrate 70108 Orientation film 70109 Liquid crystal 70110 Resin 70113 Liquid crystal injection port 70301 Substrate 70302 Orientation film 70303 Roller 70304 Rubbing roller 70305 Seal material 70306 Spacer 70307 Substrate 70308 Orientation film 70309 Liquid crystal 80300 Pixel 80301 Switching transistor 80302 Driving transistor 80303 Capacitor 80304 Light-emitting element 80305 Signal line 80306 Scanning line 80307 Power line 80308 Common electrode 80309 Rectifier 80400 Pixel 80401 Switching transistor 80402 Driving transistor 80403 Capacitor 80404 Light-emitting element 80405 Signal line 80406 Scanning line 80407 Power supply line 80408 Common electrode 80409 Rectifying element 80410 Scanning line 80500 Pixel 80501 Switching transistor 80502 Driving transistor 80503 Capacitor 80504 Light-emitting element 80505 Signal line 80506 Scanning line 80507 Power supply line 80508 Common electrode 80509 Erasing transistor 80510 Scanning line 80600 Driving transistor 80601 Switch 80602 Switch 80603 Switch 80604 Capacitor 80605 Capacitor 80611 Signal line 80612 Power supply line 80613 Scanning line 80614 Scanning line 80620 Light-emitting element 80621 Common electrode 80700 Driving transistor 80701 Switch 80702 Switch 80703 Switch 80704 Capacitive element 80711 Signal line 80712 Power line 80713 Scanning line 80714 Scanning line 80730 Light-emitting element 80731 Common electrode 80734 Scanning line 60105 Transistor 60106 Wiring 60107 Wiring 60108 Transistor 60111 Wiring 60112 Counter electrode 60113 Capacitor 60115 Pixel electrode 60116 Partition wall 60117 Organic conductive film 60118 Organic thin film 60119 Substrate 60200 Substrate 60201 Wiring 60202 Wiring 60203 Wiring 60204 Wiring 60205 Transistor 60206 Transistor 60207 Transistor 60208 Pixel electrode 60211 Partition wall 60212 Organic conductive film 60213 Organic thin film 60214 Counter electrode 60300 Substrate 60301 Wiring 60302 Wiring 60303 Wiring 60304 Wiring 60305 Transistor 60306 Transistor 60307 Transistor 60308 Transistor 60309 Pixel electrode 60311 Wiring 60312 Wiring 60321 Partition wall 60322 Organic conductive film 60323 Organic thin film 60324 Counter electrode 190101 Anode 190102 Cathode 190103 Hole transport region 190104 Electron transport region 190105 Mixed region 190106 Region 190107 Region 190108 Region 190109 Region 190260 Transfer chamber 190261 Transfer chamber 190262 Load chamber 190263 Unload chamber 190264 Intermediate treatment chamber 190265 Sealing treatment chamber 190266 Transport means 190267 Transport means 190268 Heat treatment chamber 190269 Film formation treatment chamber 190270 Film formation treatment chamber 190271 Film formation chamber 190272 Plasma treatment chamber 190273 Film formation treatment chamber 190274 Film formation treatment chamber 190276 Film formation treatment chamber 190380 Evaporation source holder 190381 Evaporation source 190382 Distance sensor 190383 Articulated arm 190384 Material supply pipe 190386 Substrate stage 190387 Substrate chuck 190388 Mask chuck 190389 Substrate 190390 Shadow mask 190391 Top plate 190392 Bottom plate 190277a Gate valve 190381a Evaporation source 190381b Evaporation source 190381c Evaporation source 190385a Material supply source 190385b Material supply source 190385c Material supply source 120100 Electrode layer 120102 Electroluminescent layer 120103 Electrode layer 120104 Insulating film 120105 Insulating film 120106 Insulating film 120200 Electrode layer 120201 Light emitting material 120202 Electroluminescent layer 120203 Electrode layer 120204 Insulating film 120205 Insulating film 120206 Insulating film 130100 Rear projection display device 130101 Screen panel 130102 Speaker 130104 Operation switches 130110 Housing 130111 Projector unit 130112 Mirror 130200 Front projection display device 130201 Projection optical system 130301 Light source unit 130302 Light source lamp 130303 Light source optical system 130304 Modulation unit 130305 Dichroic mirror 130306 Total reflection mirror 130308 Display panel 130309 Prism 130310 Projection optical system 130400 Modulation unit 130401 Dichroic mirror 130402 Dichroic mirror 130403 Total reflection mirror 130404 Polarizing beam splitter 130405 Polarizing beam splitter 130406 Polarizing beam splitter 130407 Reflective display panel 130411 Projection optical system 130501 Dichroic mirror 130502 Dichroic mirror 130503 Dichroic mirror for red light 130504 Phase difference plate 130505 Color filter plate 130506 Microlens array 130507 Display panel 130508 Display panel 130509 Display panel 130511 Projection optical system 900101 Display panel 900102 Pixel section 900103 Scanning line driving circuit 900104 Signal line driving circuit 900111 Circuit board 900112 Control circuit 900113 Signal division circuit 900114 Connection wiring 900201 Tuner 900202 Video signal amplifier circuit 900203 Video signal processing circuit 900205 Audio signal amplifier circuit 900206 Audio signal processing circuit 900207 Speaker 900208 Control circuit 900209 Input section 900212 Control circuit 900213 Signal division circuit 900301 Housing 900302 Display screen 900303 Speaker 900304 Operation switch 900305 Input means 900306 Sensor 900307 Microphone 900310 Charger 900312 Housing 900313 Display section 900316 Operation keys 900317 Speaker section 900318 Input means 900319
900320 Microphone 900401 Display panel 900402 Printed wiring board 900403 Pixel portion 900404 Scanning line driver circuit 900405 Scanning line driver circuit 900406 Signal line driver circuit 900407 Controller 900408 Central processing unit (CPU)
900409 Memory 900410 Power supply circuit 900411 Audio processing circuit 900412 Transmitting/receiving circuit 900413 Flexible printed circuit board (FPC)
900414 Interface (I/F) section 900415 Antenna port 900416 VRAM
900417 DRAM
900418 Flash memory 900419 Interface (I/F) section 900420 Control signal generating circuit 900421 Decoder 900421 One-way decoder 900422 Register 900423 Arithmetic circuit 900424 RAM
900425 Input means 900426 Microphone 900427 Speaker 900428 Antenna 900501 Display panel 900513 FPC
900530 Housing 900531 Printed circuit board 900532 Speaker 900533 Microphone 900534 Transmitting/receiving circuit 900535 Signal processing circuit 900536 Input means 900537 Battery 900539 Housing 900541 Sensor 900600 Mobile phone 900601 Main body (A)
900602 Body (B)
900603 Housing 900604 Operation switches 900605 Microphone 900606 Speaker 900607 Circuit board 900608 Display panel (A)
900609 Display panel (B)
900610 hinge 900611 sensor 900612 input means 900711 housing 900712 support base 900713 display unit 900714 input means 900715
900716 Microphone 900717 Speaker 900718 Operation keys 900719 LED lamp 900731 Main body 900732 Display unit 900733 Image receiving unit 900734 Operation keys 900735 External connection port 900736 Shutter 900737 Input means 900738 Sensor 900739 Microphone 900740 Speaker 900741 LED lamp 900751 Main body 900752 Housing 900753 Display unit 900754 Keyboard 900755 External connection port 900756 Pointing device 900757 Input means 900758
900759 Microphone 900760 Speaker 900761 LED lamp 900762 Reader/writer 900810 Housing 900811 Display section 900812 Remote control device 900813 Speaker section 900901 Display panel 900902 Unit bath 901001 Pillar body 901002 Display panel 901101 Car body 901102 Display panel 901201 Door 901202 Display panel 901203 Glass window 901204 Ceiling 901301 Ceiling 901302 Display panel 901303 Hinge section 901411 Main body 901412 Display section 901413 Switch 901414 Operation keys 901415 Infrared port 901416 Input means 901417)
901418 Microphone 901419 Speaker 901420 LED lamp 901431 Main body 901432 Housing 901433 Display section A
901434 Display part B
901435 section 901436 operation key 901437 speaker section 901438 input means 901439
901440 Microphone 901441 LED lamp 901451 Main body 901452 Display unit 901453 Earphone 901454 Support unit 901455 Input means 901456
901457 Microphone 901458 Speaker 901511 Housing 901512 Display unit 901513 Speaker unit 901514 Operation keys 901515 Storage medium insertion unit 901516 Input means 901517)
901518 Microphone 901519 LED lamp 901531 Main body 901532 Display unit 901533 Operation keys 901534 Speaker 901535 Shutter 901536 Image receiving unit 901537 Antenna 901538 Input means 901539 Sensor 901540 Microphone 901541 LED lamp 901611 Housing 901612 Display unit 901613 Display unit 901614 Speaker unit 901615 Operation keys 901616 Recording medium insertion unit 901617 Input means 901618
901619 Microphone 901620 LED Lamp

Claims (4)

The pixel electrode includes a plurality of pixels arranged in a matrix and first to third wirings,
Each of the plurality of pixels has a plurality of liquid crystal elements,
a first potential corresponding to a signal potential is supplied from the first wiring to a pixel electrode of the liquid crystal elements included in the pixel of the plurality of pixels via a first transistor included in the pixel of the plurality of pixels;
a second transistor and a third transistor included in one of the plurality of pixels are turned on, and a channel formation region of the second transistor is electrically connected to a channel formation region of the third transistor through a conductive layer that functions as at least one of a source electrode and a drain electrode of the second transistor, and the first wiring and the second wiring are electrically connected to each other through the channel formation region of the second transistor, the conductive layer, and the channel formation region of the third transistor, so that a second potential different from the first potential is supplied to a pixel electrode of another one of the plurality of liquid crystal elements included in one of the plurality of pixels;
the conductive layer is always electrically connected to the other pixel electrode,
the first wiring and the second wiring are shared by at least a plurality of pixels belonging to the same column among the plurality of pixels;
In the first transistor, in a plan view, one of the source electrode and the drain electrode has a region sandwiched by the other of the source electrode and the drain electrode,
In the second transistor, in a plan view, one of the source electrode and the drain electrode does not have a region sandwiched by the other of the source electrode and the drain electrode,
In the third transistor, one of the source electrode and the drain electrode has a region sandwiched between the other of the source electrode and the drain electrode in a plan view,
a ratio W/L of a channel width W to a channel length L of the first transistor is greater than a ratio W/L of a channel width W to a channel length L of the second transistor;
a ratio W/L of a channel width W to a channel length L of the third transistor is greater than a ratio W/L of a channel width W to a channel length L of the second transistor;
a potential of a gate electrode of the first transistor, a potential of a gate electrode of the second transistor, and a potential of a gate electrode of the third transistor are controlled by the third wiring. The pixel electrode includes a plurality of pixels arranged in a matrix and first to third wirings,
Each of the plurality of pixels has a plurality of liquid crystal elements,
a first potential corresponding to a signal potential is supplied from the first wiring to a pixel electrode of the liquid crystal elements included in the pixel of the plurality of pixels via a first transistor included in the pixel of the plurality of pixels;
a second transistor and a third transistor included in one of the plurality of pixels are turned on, and a channel formation region of the second transistor is electrically connected to a channel formation region of the third transistor through a conductive layer that functions as at least one of a source electrode and a drain electrode of the second transistor, and the first wiring and the second wiring are electrically connected to each other through the channel formation region of the second transistor, the first conductive layer, and the channel formation region of the third transistor, so that a second potential different from the first potential is supplied to a pixel electrode of another of the plurality of liquid crystal elements included in one of the plurality of pixels;
the first conductive layer is always electrically connected to the other pixel electrode;
the first wiring and the second wiring are shared by at least a plurality of pixels belonging to the same column among the plurality of pixels;
In the first transistor, in a plan view, one of the source electrode and the drain electrode has a region sandwiched by the other of the source electrode and the drain electrode,
In the second transistor, in a plan view, one of the source electrode and the drain electrode does not have a region sandwiched by the other of the source electrode and the drain electrode,
In the third transistor, one of the source electrode and the drain electrode has a region sandwiched between the other of the source electrode and the drain electrode in a plan view,
a ratio W/L of a channel width W to a channel length L of the first transistor is greater than a ratio W/L of a channel width W to a channel length L of the second transistor;
a ratio W/L of a channel width W to a channel length L of the third transistor is greater than a ratio W/L of a channel width W to a channel length L of the second transistor;
a potential of a gate electrode of the first transistor, a potential of a gate electrode of the second transistor, and a potential of a gate electrode of the third transistor are controlled by the third wiring;
a second conductive layer functioning as the third wiring has a region functioning as a gate electrode of the first transistor, a region functioning as a gate electrode of the second transistor, and a region functioning as a gate electrode of the third transistor. The pixel electrode includes a plurality of pixels arranged in a matrix and first to third wirings,
Each of the plurality of pixels has a plurality of liquid crystal elements,
a first potential corresponding to a signal potential is supplied from the first wiring to a pixel electrode of the liquid crystal elements included in the pixel of the plurality of pixels via a first transistor included in the pixel of the plurality of pixels;
a second transistor and a third transistor included in one of the plurality of pixels are turned on, and a channel formation region of the second transistor is electrically connected to a channel formation region of the third transistor through a conductive layer that functions as at least one of a source electrode and a drain electrode of the second transistor, and the first wiring and the second wiring are electrically connected to each other through the channel formation region of the second transistor, the conductive layer, and the channel formation region of the third transistor, so that a second potential different from the first potential is supplied to a pixel electrode of another one of the plurality of liquid crystal elements included in one of the plurality of pixels;
the conductive layer is always electrically connected to the other pixel electrode,
the first wiring and the second wiring are shared by at least a plurality of pixels belonging to the same column among the plurality of pixels;
a ratio W/L of a channel width W to a channel length L of the first transistor is greater than a ratio W/L of a channel width W to a channel length L of the second transistor;
a ratio W/L of a channel width W to a channel length L of the third transistor is greater than a ratio W/L of a channel width W to a channel length L of the second transistor;
a potential of a gate electrode of the first transistor, a potential of a gate electrode of the second transistor, and a potential of a gate electrode of the third transistor are controlled by the third wiring;
the first conductive layer functioning as the third wiring has a region functioning as a gate electrode of the first transistor, a region functioning as a gate electrode of the second transistor, and a region functioning as a gate electrode of the third transistor;
the first conductive layer is located in a region between a second conductive layer having a region functioning as one pixel electrode of the plurality of liquid crystal elements and a third conductive layer having a region functioning as another pixel electrode of the plurality of liquid crystal elements in a plan view;
a first conductive layer that has no region overlapping with the second conductive layer and that has no region overlapping with the third conductive layer; The pixel electrode includes a plurality of pixels arranged in a matrix and first to third wirings,
Each of the plurality of pixels has a plurality of liquid crystal elements,
a first potential corresponding to a signal potential is supplied from the first wiring to a pixel electrode of the liquid crystal elements included in the pixel of the plurality of pixels via a first transistor included in the pixel of the plurality of pixels;
a second transistor and a third transistor included in one of the plurality of pixels are turned on, and a channel formation region of the second transistor is electrically connected to a channel formation region of the third transistor through a conductive layer that functions as at least one of a source electrode and a drain electrode of the second transistor, and the first wiring and the second wiring are electrically connected to each other through the channel formation region of the second transistor, the conductive layer, and the channel formation region of the third transistor, so that a second potential different from the first potential is supplied to a pixel electrode of another one of the plurality of liquid crystal elements included in one of the plurality of pixels;
the conductive layer is always electrically connected to the other pixel electrode,
the first wiring and the second wiring are shared by at least a plurality of pixels belonging to the same column among the plurality of pixels;
In the first transistor, in a plan view, one of the source electrode and the drain electrode has a region sandwiched by the other of the source electrode and the drain electrode,
In the second transistor, in a plan view, one of the source electrode and the drain electrode does not have a region sandwiched by the other of the source electrode and the drain electrode,
In the third transistor, one of the source electrode and the drain electrode has a region sandwiched between the other of the source electrode and the drain electrode in a plan view,
a ratio W/L of a channel width W to a channel length L of the first transistor is greater than a ratio W/L of a channel width W to a channel length L of the second transistor;
a ratio W/L of a channel width W to a channel length L of the third transistor is greater than a ratio W/L of a channel width W to a channel length L of the second transistor;
a potential of a gate electrode of the first transistor, a potential of a gate electrode of the second transistor, and a potential of a gate electrode of the third transistor are controlled by the third wiring;
the first conductive layer functioning as the third wiring has a region functioning as a gate electrode of the first transistor, a region functioning as a gate electrode of the second transistor, and a region functioning as a gate electrode of the third transistor;
the first conductive layer is located in a region between a second conductive layer having a region functioning as one pixel electrode of the plurality of liquid crystal elements and a third conductive layer having a region functioning as another pixel electrode of the plurality of liquid crystal elements in a plan view;
a first conductive layer that has no region overlapping with the second conductive layer and that has no region overlapping with the third conductive layer;

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