JP2019053298A - Liquid crystal display device - Google Patents

Abstract

To provide a high-quality liquid crystal display device excellent in viewing angle characteristics.SOLUTION: A liquid crystal display device has a pixel including a first switch 111, a second switch 112, a third switch 113, a first resistance 114, a second resistance 115, a first liquid crystal device 121 and a second liquid crystal device 122, where a pixel electrode of the first liquid crystal device 121 is electrically connected to a signal line 116 through the first switch 111, the pixel electrode of the first liquid crystal device 121 is electrically connected to a pixel electrode of the second liquid crystal device 122 through the second switch 112 and the first resistance 114, the pixel electrode of the second liquid crystal device 122 is electrically connected to a Cs line 119 through the third switch 113 and the second resistance 115, and a common electrode 118 of the first liquid crystal device 121 is electrically connected to a common electrode 118 of the second liquid crystal device 122. By inputting potential to the signal line 116 according to a grayscale of the pixel, high-quality display with excellent viewing angle characteristics can be obtained.SELECTED DRAWING: Figure 1

Description

The present invention relates to an article, a method, or a method of producing an article. In particular, the present invention relates to a display device or a semiconductor device. Further, the present invention relates to an electronic device having the display device in a display portion.

Liquid crystal display devices are used in many electric products such as mobile phones and television receivers, and much research has been conducted to further improve the quality.

Liquid crystal display devices have the advantages of being smaller and lighter than CRTs (Brown tubes) and consuming less power, but have the problem of having a narrow viewing angle. In recent years, much research has been done on multi-domain methods, that is, alignment division methods in order to improve viewing angle characteristics. For example, an MVA method (Multi-domain Vertical Al) combining a multi-domain method with a VA method (Vertical Alignment; vertical alignment method)
ignment (multi-domain vertical alignment method) or PVA method (patterned)
Vertical Alignment (patterned vertical alignment method) and the like.

In addition, research has also been conducted to improve the viewing angle by dividing one pixel into a plurality of sub-pixels and changing the alignment state of the liquid crystal in each sub-pixel (Patent Document 1).

Unexamined-Japanese-Patent No. 2006-276582

However, the viewing angle characteristics are not sufficient, and further improvement is required for the display device. Therefore, it is an object of the present invention to provide a display device of higher quality with excellent viewing angle characteristics.

An equivalent circuit diagram of one pixel of the liquid crystal display device described in Patent Document 1 is shown in FIG. Figure 7
The pixel 7 has a TFT 30, a liquid crystal capacitance L1, a liquid crystal capacitance L2, a holding capacitance C1 and a holding capacitance C2, and is connected to the scanning line 3a and the data line (signal line) 6a.

Although the liquid crystal exhibits a voltage holding characteristic, its retention rate is not 100%, and there is a concern about the presence of a leak due to the flow of electric charge in the liquid crystal. In the pixel shown in FIG. 77, when leakage occurs, the state kept at a constant potential by the charge conservation law in the portion closed by the holding capacitance C1, the holding capacitance C2 and the liquid crystal capacitance L2 at the node 11 is lost. The potential of the node 11 deviates from the potential of the initial state before the leak occurs. Therefore, the transmittance of the liquid crystal capacitance L2 is
It changes from the transmittance determined by the image signal written to the data line 6a, that is, the potential according to the gradation. As a result, the desired gradation can not be obtained or the image quality is degraded. In this manner, the display quality gradually decreases with the passage of time. Thus, the product life is shortened. In particular, in a display device of the normally black mode, black can not be displayed, which causes a decrease in contrast.

In view of the above problems, it is an object of the present invention to realize a wide viewing angle display. Another object is to provide a display device with excellent contrast. Another object is to provide a display device excellent in display quality. Another object is to provide a display device which is less susceptible to noise and can perform a clear display. Another object is to provide a display device in which display deterioration is less likely to occur. Another object is to provide a display device having an excellent product life.

One embodiment of the present invention provides a first switch, a second switch, a third switch, a first resistor, a second resistor, a first liquid crystal element, and a second liquid crystal element. Each of the first liquid crystal element and the second liquid crystal element includes at least a pixel electrode, a common electrode, and a liquid crystal controlled by the pixel electrode and the common electrode; The pixel electrode of the liquid crystal element 1 is
The pixel electrode of the first liquid crystal element is electrically connected to the first wiring through the first switch, and the second liquid crystal element is connected through the second switch and the first resistor. And the pixel electrode of the second liquid crystal element is electrically connected to a second wiring through the third switch and the second resistor. Liquid crystal display device.

One embodiment of the present invention is a first switch, a second switch, a third switch, a first resistor, a second resistor, a first liquid crystal element, and a second liquid crystal element. A pixel including a first storage capacitor and a second storage capacitor, wherein each of the first liquid crystal element and the second liquid crystal element includes at least a pixel electrode, a common electrode, the pixel electrode, and the pixel electrode; The pixel electrode of the first liquid crystal element is electrically connected to the first wiring through the first switch, and the pixel electrode of the first liquid crystal element. The electrode is electrically connected to the pixel electrode of the second liquid crystal element through the second switch and the first resistor, and the pixel electrode of the second liquid crystal element is the third switch and The pixel of the first liquid crystal element is electrically connected to the second wiring through the second resistor. Poles, the first being electrically connected to the second wiring through the storage capacitor, a pixel electrode of the second liquid crystal element, the second through the second storage capacitor
The liquid crystal display device is electrically connected to the wiring of

One aspect of the present invention is a liquid crystal display device having the above structure, wherein a resistance value of the second resistor is larger than a resistance value of the first resistor.

One embodiment of the present invention includes a switch, a first transistor, a second transistor, a first liquid crystal element, a second liquid crystal element, a first storage capacitor, and a second storage capacitor. Have pixels,
Each of the first liquid crystal element and the second liquid crystal element includes at least a pixel electrode and a common electrode.
The liquid crystal device includes the liquid crystal controlled by the pixel electrode and the common electrode, and the pixel electrode of the first liquid crystal element is electrically connected to the first wiring through the switch, and the first liquid crystal element And the pixel electrode of the second liquid crystal element is electrically connected to the pixel electrode of the second liquid crystal element through the second transistor. And the pixel electrode of the first liquid crystal element is electrically connected to the second wiring through the first storage capacitor, and the pixel electrode of the second liquid crystal element The liquid crystal display device is electrically connected to the second wiring through the second storage capacitor.

One feature of the present invention is a first transistor, a second transistor, a third transistor, a first liquid crystal element, a second liquid crystal element, a first storage capacitor, and a second storage capacitor. And each of the first liquid crystal element and the second liquid crystal element includes at least a pixel electrode, a common electrode, and a liquid crystal controlled by the pixel electrode and the common electrode. The pixel electrode of the first liquid crystal element is electrically connected to the first wiring through the third transistor, and the pixel electrode of the first liquid crystal element is the first transistor through the first transistor. The pixel electrode of the second liquid crystal element is electrically connected, and the pixel electrode of the second liquid crystal element is electrically connected to the second wiring through the second transistor, and the first liquid crystal The pixel electrode of the element is connected to the first storage capacitor via the first storage capacitor. And the pixel electrode of the second liquid crystal element is electrically connected to the second wiring through the second storage capacitor. is there.

In one embodiment of the present invention, assuming that the channel width of the transistor is W and the channel length is L in the above configuration, W / L of the third transistor is higher than W / L of the first transistor or the second transistor It is a liquid crystal display device characterized by being small.

Further, one aspect of the present invention is characterized in that W / L of the second transistor is larger than W / L of the first transistor, where W is a channel width of the transistor and L is a channel length in the above configuration. It is a liquid crystal display device.

The display device of the present invention includes, for example, a liquid crystal display device, a light emitting device having a light emitting element represented by an organic light emitting element (OLED) in each pixel, and a DMD (Digital Micromirror).
Device), PDP (Plasma Display Panel), FED (F
Active matrix display devices such as an ield Emission Display are included in the category. In addition, a passive matrix display device is also included.

Note that various types of switches can be used as the switch. Examples include electrical switches and mechanical switches. In other words, anything that can control the flow of current can be used.
It is not limited to a specific one. For example, as a switch, a transistor (eg, a bipolar transistor, a MOS transistor, etc.), a diode (eg, a PN diode, P
IN diode, Schottky diode, MIM (Metal Insulator)
Metal) Diode, MIS (Metal Insulator Semicond)
uctor) a diode, a diode-connected transistor, etc.), a thyristor, etc. can be used. Alternatively, a logic circuit combining these can be used as a switch.

An example of a mechanical switch is a digital micro mirror device (DMD),
There is a switch using MEMS (micro electro mechanical system) technology. The switch has a mechanically movable electrode, and the movement of the electrode operates to control connection and disconnection.

When a transistor is used as a switch, the transistor operates as a mere switch, and thus the polarity (conductivity type) of the transistor is not particularly limited. However, in order to suppress the off current, it is preferable to use a transistor with a smaller off current. As a transistor having a small off current, there are a transistor having an LDD region, a transistor having a multi gate structure, and the like. Alternatively, an N-channel transistor is preferably used in the case where the potential of the source terminal of the transistor operated as a switch is close to the potential of the low potential power supply (Vss, GND, 0 V, etc.). On the other hand, it is desirable to use a P-channel transistor when operating with the potential of the source terminal close to the potential of the high potential side power supply (such as Vdd). This is because, in an N-channel transistor, when the source terminal operates near the potential of the low potential power supply, in a P-channel transistor, when the source terminal operates near the potential of the high power supply, Because the absolute value of the voltage between them can be increased, it is easy to operate as a switch. In addition, since the source follower operation is less likely to occur, the magnitude of the output voltage is less likely to decrease.

Note that both N-channel and P-channel transistors are used to
A type switch may be used as the switch. In the case of a CMOS switch, when either a P-channel transistor or an N-channel transistor is turned on, a current flows, so that the switch can easily function. For example, even when the voltage of the input signal to the switch is high or low, the voltage can be output appropriately. Furthermore, since the voltage amplitude value of the signal for turning on and off the switch can be reduced, the power consumption can also be reduced.

Note that in the case where a transistor is used as a switch, the switch has an input terminal (one of a source terminal or a drain terminal), an output terminal (the other of the source terminal or drain terminal), and a terminal (gate terminal) that controls conduction. doing. 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 number of wires for controlling terminals.

In the case where it is explicitly stated that A and B are connected, the case where A and B are electrically connected and the case where A and B are functionally connected , A and B are directly connected. Here, A and B each denote an object (eg, a device, an element, a circuit, a wiring, an electrode, a terminal, a conductive film, a layer, or the like). Thus, the predetermined connection relationship,
For example, the present invention is not limited to the connection relation shown in the figure or the sentence, and includes other than the connection relation shown in the figure or the sentence.

For example, in the case where A and B are electrically connected, an element (for example, a switch, a transistor, a capacitor, an inductor, a resistor, a diode, or the like) which can electrically connect A and B is used. , And A and B may be disposed one or more. Alternatively, a circuit (for example, a logic circuit (for example, an inverter, a NAND circuit, a NOR circuit, or the like) that enables functional connection of A and B as a case where A and B are functionally connected, a signal conversion circuit (DA converter circuit, AD converter circuit, gamma correction circuit etc.), potential level converter circuit (power supply circuit (boost circuit,
Step-down circuits, etc., level shifter circuits for changing the potential level of signals, etc.), voltage sources, current sources, etc.
Switching circuits, amplification circuits (circuits that can increase signal amplitude or current, etc., operational
One or more differential amplifier circuits, source follower circuits, buffer circuits, etc., signal generation circuits, memory circuits, control circuits, etc.) may be arranged between A and B. Alternatively, assuming that A and B are directly connected, without interposing other elements or other circuits between A and B, A and B.
And may be directly connected.

In the case where it is explicitly stated that A and B are directly connected, when A and B are directly connected (that is, another element or another circuit between A and B) And A and B are electrically connected (that is, A and B are connected via another element or another circuit). And (if applicable).

In the case where it is explicitly stated that A and B are electrically connected, when A and B are electrically connected (that is, another element between A and B) And when A and B are functionally connected (that is, functionally connected between A and B with another circuit). And A) and B are directly connected (that is, when A and B are connected without sandwiching another element or another circuit). That is, when explicitly described as being electrically connected, it is assumed that it is the same as the case where only being connected is explicitly described.

Note that a display element, a display device which is a device having a display element, a light emitting element, and a light emitting device which is a device having a light emitting element can have various modes and various elements. For example, as a display element, a display device, a light emitting element or a light emitting device, an EL element (an EL element containing an organic substance and an inorganic substance, an organic EL element, an inorganic EL element), an electron emitting element, a liquid crystal element, an electronic ink, an electrophoretic element, Grating light valve (GLV), plasma display (PD)
P) A digital micromirror device (DMD), a piezoelectric ceramic display, a carbon nanotube, or the like, and a display medium in which the contrast, the brightness, the reflectance, the transmittance, and the like change by electromagnetic action can be used. In addition, an EL display is a display using an EL element, and a field emission display (FED) or an SED flat display (SED: Surface-co) is a display using an electron emitting element.
Liquid crystal displays (transmissive liquid crystal display, semi-transmissive liquid crystal display, reflective liquid crystal display, direct view liquid crystal display, projection liquid crystal display), electronic As a display device using an electrophoretic element, there is electronic paper.

Note that an EL element is an element having an anode, a cathode, and an EL layer sandwiched between the anode and the cathode. As the EL layer, one using light emission (fluorescence) from singlet excitons, 3
Those using light emission (phosphorescence) from doublet excitons, those using light emission (fluorescence) from singlet excitons and those using light emission (phosphorescence) from triplet excitons , Those formed by organic matter, those formed by inorganic matter, those including those formed by organic matter and those formed by inorganic matter, high molecular materials, low molecular materials, high molecular materials and low molecules And the like can be used. However, it is not limited to this, E
Various elements can be used as the L element.

Note that an electron emitting element is an element that draws a electron by concentrating a high electric field on a sharp cathode. For example, a spint type, a carbon nanotube (CNT) type, an MIM (Metal-Insulator-Metal) type in which a metal-insulator-metal is stacked, an MIS (metal-insulator) in which a metal-insulator-semiconductor is stacked as an electron-emitting device -Semicon
ductor type, MOS type, silicon type, thin film diode type, diamond type, surface conduction emitter SCD type, orde type, diamond type, surface conduction emitter SCD type, metal-insulator-semiconductor-metal type thin film type, HEED Types, EL types, porous silicon types, surface conduction (SED) types, and the like can be used. However, the present invention is not limited to this, and various electron-emitting devices can be used.

Note that a liquid crystal element is an element that controls transmission or non-transmission of light by an optical modulation action of liquid crystal, and includes a pair of electrodes and liquid crystal. The optical modulation action of the liquid crystal is controlled by an electric field applied to the liquid crystal (including an electric field in the lateral direction, an electric field in the vertical direction, or an electric field in the oblique direction). As liquid crystal elements, nematic liquid crystal, cholesteric liquid crystal, smectic liquid crystal, discotic liquid crystal, thermotropic liquid crystal, lyotropic liquid crystal, lyotropic liquid crystal, low molecular liquid crystal, polymer liquid crystal, ferroelectric liquid crystal, antiferroelectric liquid crystal, main chain Type liquid crystal, side chain type polymer liquid crystal, plasma addressed liquid crystal (PDLC), banana type liquid crystal, TN (Twisted
Nematic) mode, STN (Super Twisted Nematic) mode, IPS (In-Plane-Switching) mode, FFS (Fringe)
Field Switching mode, MVA (Multi-domain Ver)
tical Alignment mode, PVA (Patterned Vertic)
al Alignment), ASV (Advanced Super View) mode, ASM (Axially Symmetric aligned Micro-ce)
ll) mode, OCB (Optical Compensated Birefring
ence) mode, ECB (Electrically Controlled Bir)
efringence mode, FLC (Ferroelectric Liquid)
Crystal) mode, AFLC (AntiFerroelectric Liqui
d Crystal mode, PDLC (Polymer Dispersed Liq)
uid Crystal mode, guest host mode, etc. can be used. However, without limitation thereto, various liquid crystal elements can be used.

In addition, as an electronic paper, what is displayed by molecules such as optical anisotropy and dye molecule orientation, those displayed by particles such as electrophoresis, particle movement, particle rotation, phase change, one end of a film What is displayed when moving, what is displayed by color development / phase change of molecules, what is displayed by light absorption of molecules, or what is displayed by self-emission where electrons and holes are combined . For example, as electronic paper, microcapsule type electrophoresis, horizontal movement type electrophoresis, vertical movement type electrophoresis, spherical twist ball, magnetic twist ball, cylindrical twist ball type, charged toner, electronic powder fluid, magnetophoretic type, magnetic thermosensitive Formula, electrowetting, light scattering (transparent white turbidity), cholesteric liquid crystal / photoconductive layer, cholesteric liquid crystal, bistable nematic liquid crystal, ferroelectric liquid crystal, dichroic dye / liquid crystal dispersion type, movable film, leuco dye extinguishing Color, photochromic, electrochromic, electrodeposition, flexible organic EL and the like can be used. However, it is not limited to this,
Various electronic paper can be used. Here, by using microcapsule electrophoresis, it is possible to solve the aggregation and precipitation of electrophoretic particles, which is a drawback of the electrophoresis system. The electronic powder fluid has advantages such as high-speed response, high reflectance, wide viewing angle, low power consumption, and memory performance.

In the plasma display, a rare gas is sealed by facing a substrate on which electrodes are formed on the surface and a substrate on which electrodes and minute grooves are formed on the surface and a phosphor layer is formed in the grooves at narrow intervals. It has a structure. Note that display can be performed by generating ultraviolet light by applying a voltage between the electrodes and lighting the phosphor. In addition, as a plasma display, DC
Type PDP and AC type PDP may be used. Here, as a plasma display panel, AS
W (Address While Sustain) driving, sub-frame divided into reset period, address period, sustain period ADS (Address Display Sep
arated) drive, CLEAR (Low Energy Address and R)
eduction of False Contour Sequence) driven, AL
IS (Alternate Lighting of Surfaces) method, TER
An ES (Technology of Reciprocal Susfainer) drive or the like can be used. However, the present invention is not limited to this, and various plasma displays can be used.

Note that display devices that require a light source, for example, liquid crystal displays (transmissive liquid crystal display, semi-transmissive liquid crystal display, reflective liquid crystal display, direct view liquid crystal display, projection liquid crystal display), grating light valve (GLV) As a light source of the display device, the display device using a digital micro mirror device (DMD), or the like, electroluminescence, a cold cathode tube, a hot cathode tube, an LED, a laser light source, a mercury lamp, or the like can be used. However, the light source is not limited to this, and various light sources can be used.

Note that various types of transistors can be used as the transistor. Therefore,
There is no limitation on the type of transistor used. For example, a thin film transistor (TFT) having a non-single-crystal semiconductor film typified by amorphous silicon, polycrystalline silicon, microcrystalline (also referred to as microcrystalline or semi-amorphous) silicon, or the like can be used. There are various advantages when using a TFT. For example, since manufacturing can be performed at a lower temperature than in the case of single crystal silicon, manufacturing cost can be reduced or the manufacturing apparatus can be enlarged. Since the manufacturing apparatus can be enlarged, it can be manufactured on a large substrate. Therefore, a large number of display devices can be manufactured at the same time, so manufacturing can be performed at low cost. Furthermore, since the manufacturing temperature is low, a substrate with low heat resistance can be used. Therefore, the transistor can be manufactured on a transparent substrate. Then, transmission of light in the display element can be controlled by using a transistor on a transparent substrate.
Alternatively, since the thickness of the transistor is thin, part of a film included in the transistor can transmit light. Therefore, the aperture ratio can be improved.

Note that by using a catalyst (such as nickel) when polycrystalline silicon is manufactured, crystallinity can be further improved, and a transistor with excellent electric characteristics can be manufactured. As a result, gate driver circuits (scanning line driving circuits) and source driver circuits (signal line driving circuits)
And a signal processing circuit (a signal generation circuit, a gamma correction circuit, a DA conversion circuit, etc.) can be integrally formed on the substrate.

Note that by using a catalyst (eg, nickel) when microcrystalline silicon is manufactured, crystallinity can be further improved, and a transistor with excellent electric characteristics can be manufactured. At this time, crystallinity can be improved only by heat treatment without irradiation of a laser beam. As a result, the gate driver circuit (scanning line driver circuit) and part of the source driver circuit (such as an analog switch) can be integrally formed on the substrate. Furthermore, in the case where laser light irradiation is not performed for crystallization, unevenness in crystallinity of silicon can be suppressed. Therefore, a beautiful image can be displayed.

However, polycrystalline silicon or microcrystalline silicon can be manufactured without using a catalyst (such as nickel).

Although it is desirable to improve the crystallinity of silicon to polycrystals or microcrystals for the whole panel, it is not limited thereto. The crystallinity of silicon may be improved only in a partial region of the panel. It is possible to selectively improve the crystallinity by selectively irradiating a laser beam or the like. For example, the laser light may be irradiated only to the peripheral circuit area which is an area other than the pixel. Alternatively, laser light may be emitted only to regions such as a gate driver circuit and a source driver circuit. Alternatively, laser light may be emitted only to the area of a part of the source driver circuit (for example, an analog switch). as a result,
The crystallization of silicon can be improved only in areas where the circuit needs to operate at high speed. Since the pixel region is not required to operate at high speed, the pixel circuit can be operated without any problem even if the crystallinity is not improved. Since the area for improving the crystallinity can be reduced, the manufacturing process can be shortened, the throughput can be improved, and the manufacturing cost can be reduced. In addition, since the number of manufacturing apparatuses required can be reduced, the manufacturing cost can be reduced.

Alternatively, the transistor can be formed using a semiconductor substrate, an SOI substrate, or the like. Accordingly, it is possible to manufacture a transistor with a small size, a high variation in current supply capability, and a small variation in characteristics, size, and shape. When these transistors are used, power consumption of the circuit can be reduced or integration of the circuit can be increased.

Alternatively, a transistor including a compound semiconductor or oxide semiconductor such as ZnO, a-InGaZnO, SiGe, GaAs, IZO, ITO, or SnO, or a thin film transistor in which the compound semiconductor or oxide semiconductor is thinned can be used. It can. By these, the manufacturing temperature can be lowered and, for example, the transistor can be manufactured at room temperature. As a result, the transistor can be formed directly on a substrate with low heat resistance, such as a plastic substrate or a film substrate. In addition, these compound semiconductors or oxide semiconductors are
As well as being used for the channel portion of the transistor, it can also be used for other applications. For example, these compound semiconductors or oxide semiconductors can be used as a resistor, a pixel electrode, and a transparent electrode. Furthermore, since they can be deposited or formed at the same time as transistors, cost can be reduced.

Alternatively, a transistor or the like formed using an inkjet method or a printing method can be used. They can be manufactured at room temperature, manufactured at low vacuum, or manufactured on a large substrate. In addition, since the transistor can be manufactured without using a mask (reticle), the layout of the transistor can be easily changed. Furthermore, since it is not necessary to use a resist, the material cost can be reduced and the number of processes can be reduced. Furthermore, since the film is applied only to the necessary portions, the material is not wasted and the cost can be reduced compared to the manufacturing method in which the film is formed on the entire surface and then etched.

Alternatively, a transistor or the like including an organic semiconductor or a carbon nanotube can be used. Thus, the transistor can be formed over a bendable substrate.
Therefore, it can withstand shocks.

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

Note that MOS transistors, bipolar transistors, and the like may be mixed on one substrate. Thus, low power consumption, miniaturization, high speed operation, and the like can be realized.

Other various transistors can be used.

Note that the transistor can be formed using various substrates. The type of substrate is not limited to a specific one. As a substrate on which a transistor is formed, for example, 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 (natural fibers (silk, cotton, hemp ) Synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate, cupra, rayon, regenerated polyester, etc.), leather substrates, rubber substrates, stainless steel substrates, substrates with stainless steel foils, etc. It can be used. Alternatively, the skin (skin, dermis) or subcutaneous tissue of animals such as humans may be used as a substrate. Alternatively, one substrate may be used to form a transistor, and then, the transistor may be transposed to another substrate and the transistor may be disposed on another substrate. As a substrate on which a transistor is transferred, 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 (natural fiber (silk, cotton, linen), Use synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (including acetate, cupra, rayon, regenerated polyester), leather substrates, rubber substrates, stainless steel substrates, substrates with stainless steel foils, etc. Can. Or skin of animal such as human (skin surface, dermis)
Alternatively, subcutaneous tissue may be used as a substrate. Alternatively, a transistor may be formed using a certain substrate, and the substrate may be polished and thinned. As a substrate to be polished, a single crystal substrate, an SOI
Substrate, glass substrate, quartz substrate, plastic substrate, paper substrate, cellophane substrate, stone substrate,
Wood substrates, cloth substrates (natural fibers (silk, cotton, hemp), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate, cupra, rayon, regenerated polyester, etc.), leather substrates, rubber substrates, stainless steel A still substrate, a substrate having a stainless steel foil, or the like can be used. Alternatively, the skin (skin, dermis) or subcutaneous tissue of animals such as humans may be used as a substrate. By using these substrates, formation of a transistor with good characteristics, formation of a transistor with low power consumption, manufacture of a device that is not easily broken,
Heat resistance can be imparted, weight reduction, or thickness reduction can be achieved.

Note that the configuration of the transistor can take various forms. It is not limited to a specific configuration. For example, a multi-gate structure having two or more gate electrodes may be used. In the multi-gate structure, the channel regions are connected in series, so that a plurality of transistors are connected in series. With the multi-gate structure, the off current can be reduced and the reliability can be improved by improving the withstand voltage of the transistor. Alternatively, due to the multi-gate structure, when operating in the saturation region, the drain-source current does not change so much even when the drain-source voltage changes, and the slope of the voltage-current characteristics becomes flat. it can. By utilizing the characteristic that the slope of the voltage / current characteristics is flat, it is possible to realize an ideal current source circuit or an active load having a very high resistance value. As a result, a differential circuit or current mirror circuit with good characteristics can be realized. In addition, gate electrodes may be disposed above and below the channel. With the structure in which the gate electrodes are disposed above and below the channel, the channel region is increased, and therefore, the S value can be reduced by increasing the current value or forming a depletion layer easily. When gate electrodes are disposed above and below the channel, a plurality of transistors are connected in parallel.

Alternatively, the gate electrode may be disposed above the channel region, or the gate electrode may be disposed below the channel region. Alternatively, a positive stagger structure or a reverse stagger structure may be used, the channel region may be divided into a plurality of regions, the channel regions may be connected in parallel, or the channel regions may be connected in series. Good. Also,
The source electrode or the drain electrode may overlap with the channel region (or a part thereof).
With a structure in which the source electrode and the drain electrode overlap with the channel region (or a part thereof), charge can be prevented from being accumulated in part of the channel region to prevent the operation from becoming unstable. Further, an LDD region may be provided. By providing the LDD region, the off current can be reduced or the reliability can be improved by improving the withstand voltage of the transistor. Or L
By providing the DD region, when operating in the saturation region, the drain-source current does not change so much even when the drain-source voltage changes, and the slope of the voltage-current characteristics becomes flat. it can.

Note that various types of transistors can be used and the transistors can be formed using various substrates. Therefore, all of the circuits necessary to realize a predetermined function may be formed on the same substrate. For example, all the circuits necessary for achieving a predetermined function may be formed using a glass substrate, a plastic substrate, a single crystal substrate, or an SOI substrate, and are formed using various substrates. It is also good. Since all the circuits necessary for realizing a predetermined function are formed using the same substrate, the cost can be reduced by reducing the number of parts, or the reliability can be improved by reducing the number of connections with circuit parts. Can be Alternatively, a part of the circuit necessary to realize a predetermined function is formed on one substrate, and another part of the circuit necessary to realize a predetermined function is formed on another substrate. It may be That is, all the circuits necessary to realize a predetermined function may not be formed using the same substrate. For example, part of a circuit necessary for achieving a predetermined function is formed using a transistor on a glass substrate, and another part of the circuit necessary for achieving a predetermined function is a single crystal substrate An IC chip formed on a single crystal substrate and formed on a single crystal substrate may be connected to a glass substrate by COG (Chip On Glass), and the IC chip may be disposed on the glass substrate. Or, TAB (T
It may be connected to the glass substrate using ape automated bonding) or a printed circuit board. Thus, 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 the reliability by reducing the number of connections with circuit components. In addition, circuits with high drive voltage and high drive frequency consume more power, so circuits in such parts are not formed on the same substrate, and instead, for example, on a single crystal substrate By forming a circuit of that portion and using an IC chip configured with that circuit, it is possible to prevent an increase in power consumption.

Note that one pixel represents one element capable of controlling the brightness. Therefore, as an example, one pixel represents one color element, and one color element represents brightness.
Therefore, in this case, in the case of a color display device consisting of R (red) G (green) B (blue) color elements, the minimum unit of the image is: R pixels, G pixels and B pixels. It shall be composed of three pixels. 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 RGBW (W is white). Also, R
For example, one or more colors of yellow, cyan, magenta, emerald green, vermilion, etc. may be added to GB. Also, for example, a color similar to at least one color of RGB may be
May be added to For example, R, G, B1 and B2 may be used. Both B1 and B2 are blue but have slightly different frequencies. Similarly, R1, R2, G, and B may be used. By using such color elements, it is possible to perform display closer to the real thing. Alternatively, power consumption can be reduced by using such a color element. Also,
As another example, when using a plurality of regions to control brightness for one color element,
One area may be one pixel. Therefore, as an example, when performing area gradation or having sub-pixels (sub-pixels), there is a plurality of areas for controlling the brightness for one color element, and the gradation is represented in its entirety. However, one pixel of the area for controlling the brightness may be set as one pixel. Therefore, in this case, one color element is composed of a plurality of pixels. Alternatively, even if there are a plurality of regions for controlling the brightness in one color element, they may be put together and one color element may be one pixel. Therefore, in this case, one color element is composed of one pixel. Further, when brightness is controlled using a plurality of areas for one color element, the size of the area contributing to display may differ depending on the pixel. In addition, in a plurality of brightness control areas for one color element, the viewing angle may be expanded by slightly different signals supplied to each. In other words, 1
The potentials of pixel electrodes included in each of a plurality of regions of one color element may be different from one another. As a result, the voltage applied to the liquid crystal molecules differs depending on each pixel electrode. Therefore, the viewing angle can be widened.

In the case where one pixel (for three colors) is explicitly described, it is assumed that three pixels of R, G, and B are considered as one pixel. In the case of explicitly describing one pixel (one color), when there are a plurality of regions for one color element, it is assumed that they are collectively considered as one pixel.

Note that in this document (specification, claims, drawings, and the like), pixels may be arranged (arranged) in matrix. Here, that the pixels are arranged (arranged) in a matrix includes the case where the pixels are arranged in a straight line or in a jagged line in the vertical direction or the horizontal direction. Thus, for example, three color elements (eg R
In the case of performing full-color display in GB), the case where stripes are arranged, and the case where dots of three color elements are deltaly arranged are also included. Furthermore, it includes the case where it is arranged in Bayer. The color elements are not limited to three colors, and may be more than three colors, for example, RGBW (W is white), or one obtained by adding one or more colors of yellow, cyan, magenta, etc. to RGB.
In addition, the size of the display area may be different for each dot of the color element. Accordingly, power consumption can be reduced or the lifetime of the display element can be lengthened.

Note that an active matrix method in which an active element is included in a pixel or a passive matrix method in which an active element is not included in a pixel can be used.

In the active matrix method, not only transistors but also various active elements (active elements, non-linear elements) can be used as active elements (active elements, non-linear elements). For example, MIM (Metal Insulator Metal) or TFD
It is also possible to use Thin Film Diode) or the like. Since these elements have few manufacturing steps, the manufacturing cost can be reduced or the yield can be improved. Furthermore, since the size of the element is small, the aperture ratio can be improved, and power consumption and brightness can be reduced.

In addition to the active matrix method, it is also possible to use a passive matrix type which does not use an active element (active element, non-linear element). Since no active element (active element, non-linear element) is used, the number of manufacturing steps is reduced, and the manufacturing cost can be reduced or the yield can be improved. In addition, since an active element (an active element or a non-linear element) is not used, the aperture ratio can be improved, and power consumption and brightness can be improved.

Note that a transistor is an element having at least three terminals of a gate, a drain, and a source, and has a channel region between the drain region and the source region, and the drain region, the channel region, and the source region The current can flow through the Here, since the source and the drain change depending on the structure, the operating condition, and the like of the transistor, it is difficult to define which is the source or the drain. Therefore, in this document (specification, claims, drawings, and the like), a region functioning as a source and a drain may not be referred to as a source or a drain. In that case, as an example, each may be described as a 1st terminal and a 2nd terminal. Alternatively, each may be referred to as a first electrode and a second electrode. Alternatively, they may be referred to as a source region and a drain region.

Note that the transistor may be an element having at least three terminals including a base, an emitter, and a collector. Also in this case, the emitter and the collector are connected to the first terminal, the second
It may be written as a terminal.

Note that a gate refers to the whole or a part of a gate electrode and a gate wiring (also referred to as a gate line, a gate signal line, a scan line, a scan signal line, or the like). The gate electrode means a conductive film in a portion overlapping with a semiconductor forming a channel region via a gate insulating film. Note that part of the gate electrode is an LDD (Lightly Dop).
In some cases, the gate insulating film overlaps with the ed drain region or the source region (or the drain region). The gate wiring refers to a wiring for connecting between gate electrodes of each transistor, a wiring for connecting between gate electrodes of each pixel, or a wiring for connecting a gate electrode to another wiring. Say.

However, there are portions (regions, conductive films, wirings, and the like) which also function as gate electrodes and also function as gate wirings. Such a portion (a region, a conductive film, a wiring, or the like) may be called a gate electrode or may be called a gate wiring. That is, there is also a region where the gate electrode and the gate wiring can not be clearly distinguished. For example, in the case where a part of the gate wiring which is extended and arranged overlaps with the channel region, that part (a region, a conductive film, a wiring, or the like) functions as a gate wiring. It will be working. Thus, such a portion (a region, a conductive film, a wiring, or the like) may be called a gate electrode or a gate wiring.

Note that a portion (a region, a conductive film, a wiring, or the like) which is formed using the same material as the gate electrode and in which the same island (island) as the gate electrode is formed may be called a gate electrode. Similarly, a portion (a region, a conductive film, a wiring, or the like) which is formed using the same material as the gate wiring and in which the same island (island) as the gate wiring is formed may be called a gate wiring. In a strict sense, such a portion (a region, a conductive film, a wiring, or the like) may not overlap with the channel region or may not have a function of connecting to another gate electrode. However, a portion (region, conductive film, wiring, etc.) which is formed of the same material as the gate electrode or the gate wiring in relation to the specifications at the time of manufacture, etc. and forms the same island as the gate electrode or the gate wiring. There is. Therefore, such a portion (a region, a conductive film, a wiring, or the like) may also be called a gate electrode or a gate wiring.

For example, in a multi-gate transistor, one gate electrode and another gate electrode are often connected by a conductive film formed of the same material as the gate electrode. Such a portion (a region, a conductive film, a wire, etc.) is a portion (a region, a conductive film, a wire, etc.) for connecting the gate electrode and the gate electrode, and may be called a gate wire. Since the transistor of the above can be regarded as one transistor, it may be called a gate electrode. That is, a portion (a region, a conductive film, a wiring, or the like) which is formed using the same material as the gate electrode or the gate wiring and which forms the same island as the gate electrode or the gate wiring (a region, a conductive film, a wiring, or the like) You may call me. Furthermore, for example, a conductive film of a portion connecting the gate electrode and the gate wiring, and formed of a material different from the gate electrode or the gate wiring may also be called a gate electrode, or the gate wiring You may call it.

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

Note that in the case where a gate wiring, a gate line, a gate signal line, a scanning line, a scanning signal line, or the like is referred to, the gate of the transistor may not be connected to the wiring. In this case, the gate wiring, the gate line, the gate signal line, the scan line, and the scan signal line are formed at the same time as a wiring formed in the same layer as the gate of the transistor, a wiring formed of the same material as the gate of the transistor, or the gate of the transistor It may mean a deposited film. Examples include a storage capacitance wiring, a power supply line, a reference potential supply wiring, and the like.

Note that a source refers to the whole or a part of a source region, a source electrode, and a source wiring (also referred to as a source line, a source signal line, a data line, a data signal line, and the like). The source region refers to a semiconductor region containing a large amount of P-type impurities (such as boron and gallium) and N-type impurities (such as phosphorus and arsenic). Therefore, a region containing a small amount of P-type impurities or N-type impurities, that is, a so-called lightly doped drain (LDD) region is not included in the source region. The source electrode refers to a conductive layer in a portion which is formed of a material different from that of the source region and electrically connected to the source region. However, the source electrode may also be referred to as a source electrode including the source region. A source wiring is a wiring for connecting between source electrodes of each transistor, a wiring for connecting between source electrodes of each pixel, or a wiring for connecting a source electrode and another wiring. Say.

However, there are portions (regions, conductive films, wirings, and the like) which also function as source electrodes and also function as source wirings. Such a portion (a region, a conductive film, a wiring, or the like) may be called a source electrode or may be called a source wiring. That is, there is also a region where the source electrode and the source wiring can not be clearly distinguished. For example, in the case where a part of the source wiring which is extended and arranged overlaps with the source region, the part (a region, a conductive film, a wiring, or the like) functions as a source wiring, but as a source electrode Is also working. Therefore, such a portion (a region, a conductive film, a wiring, or the like) may be called a source electrode or may be called a source wiring.

Note that a portion (a region, a conductive film, a wiring, or the like) which is formed using the same material as the source electrode and forms the same island (island) as the source electrode (a region, a conductive film, a wiring, or the like) , A conductive film, a wiring, and the like) may also be referred to as a source electrode. Furthermore, a portion overlapping with the source region may also be called a source electrode. Similarly, a region which is formed of the same material as the source wiring and in which the same island (island) as the source wiring is formed and connected may be referred to as a source wiring. In a strict sense, such a portion (a region, a conductive film, a wiring, or the like) may not have a function of connecting to another source electrode. However, there is a portion (a region, a conductive film, a wiring, or the like) which is formed of the same material as the source electrode or the source wiring and is connected to the source electrode or the source wiring due to specifications in manufacturing. Therefore, such a portion (a region, a conductive film, a wiring, or the like) may also be called a source electrode or a source wiring.

Note that, for example, a conductive film in a portion connecting a source electrode and a source wiring and formed of a material different from that of the source electrode or the source wiring may also be called a source electrode, or the source wiring You may call it.

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

Note that when you refer to a source wiring, a source line, a source signal line, a data line, a data signal line, etc.,
In some cases, the source (drain) of the transistor is not connected to the wiring. In this case, the source wiring, the source line, the source signal line, the data line, and the data signal line are formed in the same layer as the source (drain) of the transistor, and formed in the same material as the source (drain) of the transistor Alternatively, it may mean a wiring formed at the same time as the source (drain) of the transistor. Examples include a storage capacitance wiring, a power supply line, a reference potential supply wiring, and the like.

The drain is the same as the source.

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

Note that display elements include optical modulation elements, liquid crystal elements, light emitting elements, EL elements (organic EL elements, inorganic EL elements, or EL elements containing organic and inorganic substances), electron emission elements, electrophoresis elements, discharge elements, light reflection It refers to elements, light diffraction elements, digital micro mirror devices (DMDs), etc. However, it is not limited to this.

Note that a display device refers to a device having a display element. Note that the display device may include a plurality of pixels including a display element. Note that the display device may include a peripheral driver circuit that drives a plurality of pixels. Note that the peripheral driver circuit for driving the plurality of pixels may be formed on the same substrate as the plurality of pixels. Note that the display device includes peripheral drive circuits arranged on a substrate by wire bonding, bumps, etc., so-called IC chips connected by chip on glass (COG), or IC chips connected by TAB or the like. It may be Note that the display device may include a flexible printed circuit (FPC) to which an IC chip, a resistor, a capacitor, an inductor, a transistor, or the like is attached. Note that the display device may include a printed wiring board (PWB) which is connected through a flexible printed circuit (FPC) or the like and to which an IC chip, a resistor, a capacitor, an inductor, a transistor, or the like is attached. The display device may include an optical sheet such as a polarizing plate or a retardation plate. Note that the display device may include a lighting device, a housing, an audio input / output device, a light sensor, and the like. Here, the illumination device such as the backlight unit may include a light guide plate, a prism sheet, a diffusion sheet, a reflection sheet, a light source (such as an LED or a cold cathode tube), a cooling device (a water cooling system, an air cooling system), etc. good.

Note that a lighting device refers to a device including a backlight unit, a light guide plate, a prism sheet, a diffusion sheet, a reflective sheet, a light source (such as an LED, a cold cathode tube, a hot cathode tube), a cooling device, and the like.

Note that a light-emitting device refers to a device including a light-emitting element or the like. In the case where a light emitting element is included as the display element, the light emitting device is one of the specific examples of the display device.

Note that a reflection device refers to a device having a light reflection element, a light diffraction element, a light reflection electrode, and the like.

Note that a liquid crystal display device refers to a display device including a liquid crystal element. Liquid crystal display devices include a direct view type, a projection type, a transmission type, a reflection type, and a semi-transmission type.

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

Note that a display device, a semiconductor device, a lighting device, a cooling device, a light-emitting device, a reflection device, a driver, and the like may overlap with each other. For example, the display device may include a semiconductor device and a light emitting device. Alternatively, the semiconductor device may include a display device and a driver.

When it is explicitly stated that B is formed on A or B is formed on A, it is limited to B being formed in direct contact with A. I will not. It also includes the case where there is no direct contact, that is, when another object intervenes between A and B. Here, A and B each represent an object (for example, a device, an element, a circuit, a wiring, an electrode, a terminal, a conductive film, a layer,
Etc.).

Thus, for example, layer B is formed directly on top of layer A if it is explicitly stated that layer B is formed on (or on) layer A. The case where another layer (for example, layer C, layer D, etc.) is formed directly in contact with the top of layer A, and the layer B is formed directly in contact with it is included. Note that another layer (eg, layer C, layer D, etc.) may be a single layer or multiple layers.

Furthermore, the same applies to the case where it is explicitly stated that B is formed above A, and it is not limited to the fact that B is in direct contact with A, but between A and B. Also includes the case where another object intervenes. Thus, for example, in the case where the layer B is formed above the layer A, the case where the layer B is formed directly on the layer A, and another layer directly on the layer A This includes the case where (for example, layer C, layer D, etc.) is formed, and layer B is formed on and in direct contact therewith. Note that another layer (eg, layer C, layer D, etc.) may be a single layer or multiple layers.

In addition, when stated explicitly that B is formed in direct contact with A, it includes the case where B is formed in direct contact with A, and another between A and B It does not include when an object intervenes.

The same applies to the case where B is below A or B is below A.

In addition, about what is explicitly described as singular, it is desirable that it is singular.
However, it is not limited to this, It is also possible to be plural. Similarly, it is desirable that a plurality be explicitly stated as a plurality. However, the invention is not limited thereto, and may be singular.

According to the present invention, a wide viewing angle display can be realized. In addition, a display device excellent in contrast can be obtained. Further, a display device excellent in display quality can be provided.
In addition, a display device which is less susceptible to noise and can perform a clear display can be provided. Alternatively, a display device in which display deterioration is less likely to occur can be provided. Alternatively, a display device with excellent product life can be provided.

FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 5 illustrates an example of a display device having a pixel of the present invention. 5A to 5C illustrate an example of a structure of a pixel included in a display device of the present invention. FIG. 13 is a view for explaining one operation method of the pixel shown in FIG. 12; FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 5 illustrates an example of a display device having a pixel of the present invention. FIG. 21 is a diagram illustrating a signal line switching circuit included in the display device illustrated in FIG. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. FIG. 2 is a diagram showing an example of a pixel configuration of the present invention. The figure which shows one structural example of the display apparatus which concerns on this invention. The figure which shows one structural example of the display apparatus which concerns on this invention. The figure which shows one structural example of the display apparatus which concerns on this invention. FIG. 6 is a diagram showing an example of the layout of pixels of the display device according to the present invention. FIG. 7 is a diagram for explaining a liquid crystal mode of a display device according to the present invention. FIG. 7 is a diagram for explaining a liquid crystal mode of a display device according to the present invention. FIG. 7 is a diagram for explaining a liquid crystal mode of a display device according to the present invention. FIG. 7 is a diagram for explaining a liquid crystal mode of a display device according to the present invention. The figure which shows one structural example of the display apparatus which concerns on this invention. The figure which shows one structural example of the display apparatus which concerns on this invention. The figure which shows one structural example of the display apparatus which concerns on this invention. The figure which shows an example of the peripheral component of the display apparatus which concerns on this invention. The figure which shows an example of the peripheral component of the display apparatus which concerns on this invention. The figure which shows an example of the peripheral component of the display apparatus which concerns on this invention. The figure which shows an example of the peripheral component of the display apparatus which concerns on this invention. FIG. 5 is a diagram showing an example of a panel circuit configuration of a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. 5A to 5C illustrate an example of a structure of a transistor included in a display device according to the present invention. 5A to 5C illustrate an example of a structure of a transistor included in a display device according to the present invention. 5A to 5C illustrate an example of a structure of a transistor included in a display device according to the present invention. 5A to 5C illustrate an example of a structure of a transistor included in a display device according to the present invention. 5A to 5C illustrate an example of a structure of a transistor included in a display device according to the present invention. The figure which shows one structural example of the display apparatus which concerns on this invention. The figure which shows one structural example of the display apparatus which concerns on this invention. The figure which shows one structural example of the display apparatus which concerns on this invention. The figure which shows one structural example of the display apparatus which concerns on this invention. FIG. 7 is a diagram showing an electronic device using a display device according to the present invention. FIG. 7 is a diagram showing an electronic device using a display device according to the present invention. FIG. 7 is a diagram showing an electronic device using a display device according to the present invention. FIG. 7 is a diagram showing an electronic device using a display device according to the present invention. FIG. 7 is a diagram showing an electronic device using a display device according to the present invention. FIG. 7 is a diagram showing an electronic device using a display device according to the present invention. FIG. 7 is a diagram showing an electronic device using a display device according to the present invention. FIG. 7 is a diagram showing an electronic device using a display device according to the present invention. FIG. 7 is a diagram showing an electronic device using a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. FIG. 7 is a diagram showing an example of a method of driving a display device according to the present invention. The figure explaining a prior art.

Hereinafter, one embodiment of the present invention will be described. However, it will be readily understood by those skilled in the art that the present invention can be practiced in many different ways and that various changes in form and detail can be made without departing from the spirit and scope of the present invention. Be done. Therefore, the present invention is not construed as being limited to the description of the present embodiment. Note that in the structures of the present invention described below, reference numerals denoting the same parts are used in common between different drawings, and the description thereof is omitted.

Embodiment 1
The basic configuration of the pixel of the present invention will be described with reference to FIG. The pixel illustrated in FIG. 1 includes a first switch 111, a second switch 112, a third switch 113, a first resistor 114, a second resistor 115, a first liquid crystal element 121, and a second liquid crystal element 122. , First holding capacity 131
And a second holding capacity 132. In addition, the pixel is connected to the signal line 116 and the Cs line 119. Note that each of the first liquid crystal element 121 and the second liquid crystal element 122 includes a pixel electrode, a common electrode 118, and a liquid crystal controlled by the pixel electrode and the common electrode 118.

In FIG. 1, the pixel electrode of the first liquid crystal element 121 is connected to the signal line 116 through the first switch 111. In addition, the pixel electrode of the first liquid crystal element 121 is connected to the second switch 1.
It is also connected to the pixel electrode of the second liquid crystal element 122 via the 12 and the first resistor 114. Assuming that the connection point between the first resistor 114 and the pixel electrode of the second liquid crystal element 122 is a node 142, the node 142 is connected to the Cs line 119 through the third switch 113 and the second resistor 115.
And connected. Further, a connection point between the second switch 112 and the wiring to which the pixel electrode of the first liquid crystal element 121 and the first switch 111 are connected is referred to as a node 141.

The on / off of the first switch 111, the second switch 112, and the third switch 113 is controlled by, for example, a signal input to the scanning line 117 as shown in FIG.

Further, an image signal corresponding to a video signal, that is, a potential according to the gradation of a pixel is input to the signal line 116.

Although the liquid crystal element exhibits a voltage holding characteristic but its holding ratio is not 100%, the first liquid crystal element 121 and the second liquid crystal element are shown in the pixel shown in FIGS. 1 and 2 in order to maintain the held voltage. A first storage capacitor 131 and a second storage capacitor 132 are provided corresponding to each of the liquid crystal elements 122. Specifically, the pixel electrode of the first liquid crystal element 121 is connected to the Cs line 119 via the first storage capacitor 131, and the pixel electrode of the second liquid crystal element 122 is the second storage capacitor 13.
2 is connected to the Cs line 119. Note that the voltage holding characteristics of the liquid crystal element depend on the liquid crystal material, the impurities mixed in the liquid crystal, the size of the pixel, etc. Therefore, when the voltage holding ratio of the liquid crystal element is high, a holding capacitance is particularly provided It does not have to be. Further, for example, when the second liquid crystal element 122 contributes less to the display than the first liquid crystal element 121, the second storage capacitor provided for the second liquid crystal element 122 which contributes less to the display 132 may be omitted.

Further, in FIG. 1, the node 141 is connected to the node 142 via the second switch 112 and the first resistor 114 in this order, but the first resistor 114 and the second switch 112 are connected in this order. Also good. In addition, node 142 has a second resistor 115 and a third switch 11.
It may be connected to the Cs line 119 via 3 in order. Of course, as shown in FIG. 27, in the second switch 112 and the first resistor 114, and in the third switch 113 and the second resistor 115, the connection relationship between the switch and the resistor may be reversed.

Further, each of the first liquid crystal element 121 and the second liquid crystal element 122 may be configured of a plurality of liquid crystal elements. Similarly, each of the first storage capacitor 131 and the second storage capacitor 132 may be configured of a plurality of storage capacitors. For example, as shown in FIG.
21 and the second liquid crystal element 122 from the two liquid crystal elements, the first holding capacitance 131, the second
The case where each of the storage capacitances 132 of is composed of two storage capacitances is shown.

Next, the operation of the above-described pixel will be described with reference to FIG. First switch 111, second
ON and OFF of the switch 112 and the third switch 113 are controlled by inputting a signal to the scanning line 117, and here, the scanning line 117 is at high level (hereinafter referred to as H level).
A case where the first switch 111, the second switch 112, and the third switch 113 are turned on by inputting the signal will be described. In this case, when a low level (hereinafter referred to as L level) is input to the scanning line 117, these switches are turned off.

First, when the scanning line 117 becomes H level, the first switch 111 and the second switch 112
The third switch 113 is turned on, and the potential corresponding to the gradation of the pixel input from the signal line 116 is supplied to the pixel electrode of the first liquid crystal element 121 and the first storage capacitor 131 via the first switch 111. Is supplied to the first electrode of the Further, this potential is supplied to the pixel electrode of the second liquid crystal element 122 and the first electrode of the second storage capacitor 132 through the second switch 112 and the first resistor 114. Note that the potential supplied to the pixel electrode of the second liquid crystal element 122 and the first electrode of the second storage capacitor 132 is the same as the potential at the node 142, and the potential is the potential difference between the node 141 and the Cs line 119 And the resistance value of the first resistor 114 and the second resistor 115. That is, to the pixel electrode of the second liquid crystal element 122, the signal line 11 is
A potential obtained by resistance division by the first resistor 114 and the second resistor 115 is supplied according to the gradation of the pixel input from 6. Note that the potential supplied to the signal line 116 according to the gradation of the pixel is Vsig, the resistance value of the first resistor 114 is R1, the resistance value of the second resistor 115 is R2, the potential supplied to the Cs line 119 Where the potential of node 141 is Vsig
The potential of the node 142 is Vcs + (Vsig−Vcs) × R2 / (R1 + R2).

Further, the first holding capacitor 131 has a potential and Cs corresponding to the gradation input from the signal line 116.
The potential difference between the potential of the line 119 and the potential of the second storage capacitor 132 is divided by the resistance and the Cs line 1.
The potential difference with the potential of 19 is maintained.

Next, an L level is input to the scan line 117. Then, the first switch 111, the second switch 112, and the third switch 113 are turned off, and the signal line 116 and the first liquid crystal element 121 are turned off.
And the second liquid crystal elements 122 are electrically disconnected from each other. However, the first storage capacitor 131 holds the potential difference between the potential according to the gradation input from the signal line 116 and the potential of the Cs line 119, and the second storage capacitor 132 has a potential divided by resistance. The potential difference with the potential of the Cs line 119 is maintained. Therefore, the pixel electrode of the first liquid crystal element 121 can maintain the potential according to the gradation of the pixel input from the signal line 116, and the potential of the pixel electrode of the second liquid crystal element 122 is also divided by resistance Can be maintained.

In this manner, the gradation of the pixel is expressed using the potential difference, that is, the voltage held by the first liquid crystal element 121 and the second liquid crystal element 122. First liquid crystal element 121 and second liquid crystal element 12
In the case of No. 2 and No. 2, different voltages are applied, so that liquid crystals included in each liquid crystal element can exhibit different orientations. Therefore, the viewing angle characteristics can be improved. Note that since the gray scale represented by a pixel is determined by the alignment of liquid crystals in each of the first liquid crystal element 121 and the second liquid crystal element 122 in the pixel, the potential supplied from the signal line 116 takes these into consideration. Need to decide. As described above, since the alignment of the first liquid crystal element 121 and the second liquid crystal element 122 can be controlled by one signal line 116, the aperture ratio of the pixel can be increased.

By the way, in the case of such a pixel configuration, the second liquid crystal element 122 is the first liquid crystal element 1.
Compared to 21, the applied voltage is smaller. Therefore, the second resistor 115 is a first resistor 1
If it is smaller than 14, the voltage applied to the second liquid crystal element 122 may be smaller than the threshold voltage of the liquid crystal, and the liquid crystal of the second liquid crystal element 122 may not be driven. Therefore,
The resistance value R2 of the second resistor 115 is larger than the resistance value R1 of the first resistor 114 (R2> R
1) is preferred. Needless to say, the relationship between the resistance values is not limited to this, as long as the liquid crystals of the first liquid crystal element 121 and the second liquid crystal element 122 can be driven to express gray scales using both liquid crystals. The threshold voltage of the liquid crystal refers to the critical value of the voltage required for driving the liquid crystal.

In addition, the resistance value of the first resistor 114 and the second resistor 115 is large, and the second switch 112
If the potential at the time of being input from the signal line 116 can be maintained even after the first switch 111 is turned off in each of the node 141 and the node 142 even without the third switch 113, these switches are provided particularly It does not have to be. For example, if the resistance value of the first resistor 114 is large, the second switch 112 provided between the node 141 and the node 142 may be omitted, and if the resistance value of the second resistor 115 is large, the node 142 And the Cs line 119 may be omitted. Of course, if both are large, the second switch 112 and the third switch 113 can be omitted.

Note that various types of switches can be used for the first switch 111, the second switch 112, and the third switch 113, and an electrical switch, a mechanical switch, or the like can be applied. . That is, it is not limited to a specific one as long as the flow of current can be controlled. For example, a transistor or a diode may be used, or a logic circuit combining these may be used.

Further, the first resistor 114 and the second resistor 115 can be realized using various elements. That is, since it can be realized using a device that causes a voltage drop when current flows, it is not limited to the resistance element. For example, a transistor, a diode, a capacitor, an inductor, or the like can be used. As a diode, PN diode, PIN diode,
An MIM diode, a Schottky diode, a diode-connected transistor, or the like can be used. As a resistance element, a silicon layer, a silicon layer (a concentration similar to that of LDD) lightly doped with an impurity, a silicon layer (a concentration similar to a source region and a drain region) doped with a large amount of impurity, ITO or IZO Or the like, a conductor whose wiring length is increased, or the like can be used. Although the case where the switch and the resistor are separately provided is described in FIGS. 1 to 3, the invention is not limited to this. One element may be used to realize the switch and the resistor.

As shown in FIG. 4, a second transistor 212 and a third transistor 213 are used for the second switch 112 and the third switch 113 in FIG. 2, respectively, and the on resistances of these transistors are used in FIG. The first resistor 114 and the second resistor 115 may be realized, and these resistors may be omitted. As described above, the second resistor 11
It is preferable that the resistance value R2 of 5 is larger than the resistance value R1 of the first resistor 114 (R2> R1), so that the on-resistance of the third transistor 213 is higher than that of the second transistor 212 The larger the resistance, the better. Thus, the second transistor 212
Channel width W2, channel length L2 and third transistor 213 channel width W3
When the channel length is L3, it is preferable to use a transistor such that W2 / L2> W3 / L3. However, it is not necessarily limited to this relationship. Of course, the configuration of the pixel is not limited to this, and for example, as shown in FIG. 5, the second transistor 112 and the third switch 113 in FIG.
12, the resistor may not be omitted by using the third transistor 213.

In addition, a transistor (here, referred to as a first transistor) is used as the first switch 111.
In the case where is used, it is preferable that the on resistance of the first transistor is lower, and if the channel width of the first transistor is W1 and the channel length is L1, W1 / L1 is preferably larger. Referring to FIG. 6, in the configuration shown in FIG.
It shows about the case where 11 is used. Note that when the first transistor 211 is compared with the second transistor 212 and the third transistor 213, W1 / L1> W2 / L2> W
It is preferable to use a transistor with 3 / L3. However, it is not necessarily limited to this.

Further, in order to increase the on resistance of the third transistor 213, a multi-gate transistor in which two transistors are connected in series to the transistor 313 as shown in FIG. 7 may be used. Although FIG. 7 shows the case where two transistors are connected in series, the number of transistors connected in series is not particularly limited.

The channel length L of the transistor 313 functions as the sum of the channel lengths of the respective transistors when the channel widths W of the two transistors connected in series are equal. Therefore, W / L tends to be smaller, and the on-resistance can be increased. Thus, the on resistance of the transistor 313 can be easily increased as compared to the on resistance of the second transistor 212 by using a multi-gate transistor.

Further, for example, when the on resistance of the third transistor 213 is very small compared to the second transistor 212, the voltage applied to the second liquid crystal element 122 is the second liquid crystal element 122.
In the case where the threshold voltage of the liquid crystal is less than or equal to that of the third transistor 213, a diode-connected transistor 414 may be provided in series with the third transistor 213 as a resistor as shown in FIG. By the diode-connected transistor 414, the second storage capacitor 132 can hold a voltage which is at least a threshold voltage of the transistor 414.
Therefore, the second liquid crystal element 1 is formed by using the diode-connected transistor 414.
22 can increase the voltage applied to the second liquid crystal element 122 more reliably.
Can drive the liquid crystal that it has. The diode has non-linearity and is particularly effective in such a case because the resistance value is higher in the low voltage region. Of course, it is also possible to use a resistor. Note that here, the potential corresponding to the gray level input from the signal line 116 is illustrated as being positive, and an n-channel transistor is used as the transistor 414, and the drain electrode of the n-channel transistor is used as the third transistor 213. An example of connection is shown. Of course, a p-channel transistor can also be used as the transistor 414. However, in this case, a source electrode is connected to the third transistor 213.

In the normal liquid crystal display device, positive and negative image signals centering on the potential of the common electrode, that is, positive and negative image signals are alternately supplied through the signal line every one frame period. In such a case, the image signal is a signal that is positive and negative with respect to the potential supplied to the Cs line. Therefore, the potential of the Cs line 119 may be changed between when a positive image signal is input and when a negative image signal is input. That is, the potential of the Cs line 119 may be lower when a negative signal is input than when a positive signal is input. Thereby, a voltage can be appropriately supplied to each pixel electrode. The pixel shown in FIG. 8 may be configured as shown in FIG. 9 so as to be able to correspond to both positive and negative image signals. The pixel shown in FIG. 9 is configured to further include a diode-connected transistor 614 in parallel with the diode-connected transistor 414 in FIG. Note that in the case where these transistors are transistors of the same conductivity type, the transistors 414 and 614 are connected so that the drain electrodes are different from each other. With such a configuration, the Cs line 1
Even if the relationship between the potential 19 and the potential supplied from the signal line 116 is reversed, the second storage capacitor 13
2 can hold a voltage higher than at least the threshold voltage of the transistor 414 or the transistor 614. Accordingly, the voltage applied to the second liquid crystal element 122 can be increased, and the liquid crystal included in the second liquid crystal element 122 can be more reliably driven. Even when such a driving method is not performed, the pixel configuration shown in FIG. 9 may be used.

In this specification, a positive voltage is applied to the liquid crystal element when the potential of the pixel electrode is higher than that of the common electrode, and a negative voltage is applied to the liquid crystal element when the potential of the common electrode is higher than the pixel electrode. It is written that it was done. Further, an image signal input from the signal line when a positive voltage is applied to the liquid crystal element is a positive signal, and an image signal input from the signal line when a negative voltage is applied is a negative electrode. Expressed as a sex signal.

Further, although different potentials may be supplied to the common electrode 118 and the Cs line 119 in this specification, the same potential may be supplied. Also, as shown in FIG.
18 and the Cs line 119 may be shared. Note that FIG. 10 shows the case where the common electrode 118 and the Cs line 119 in FIG.

  Subsequently, a display device having the above-described pixel of the present invention will be described with reference to FIG.

The display device includes a signal line driver circuit 511, a scan line driver circuit 512, and a pixel portion 513.
In the pixel portion 513, a plurality of signal lines S1 to Sm arranged extending in the column direction from the signal line driving circuit 511, scanning lines G1 to Gn extending in the row direction from the scanning line driving circuit 512, and A plurality of pixels 514 arranged in a matrix corresponding to Cs lines Cs_1 to Cs_n and signal lines S1 to Sm are provided. Each pixel 514 is connected to a signal line Sj (signal lines S1 to S
Any one of m), a scanning line Gi (any one of scanning lines G1 to Gn), and a Cs line Cs_i are connected.

Note that the signal line Sj, the scanning line Gi, and the Cs line Cs_i correspond to the signal line 116, the scanning line 117, and the Cs line 119 in FIG. 2, respectively. The common electrode 118 in FIG.
The four are commonly or electrically connected, and the same potential is supplied. Note that in the case where the Cs line 119 and the common electrode 118 have the same potential, conductive fine particles, wirings, or the like may be electrically connected outside the pixel portion 513.

A row of pixels to be operated is selected according to a signal input from the scan line drive circuit 512 to the scan line Gi, and each pixel belonging to the selected row is selected from the signal line drive circuit 511 via the signal lines S1 to Sm. Supply a potential according to the gradation of The pixel can express gradation as described above by the potential supplied from the signal line Sj.

Note that in order to suppress display unevenness such as deterioration or flicker of the liquid crystal material, the polarity of the voltage applied to the pixel electrode is inverted with respect to the potential (common potential) of the common electrode in the liquid crystal element every fixed period. It is preferable to use a reverse drive which is driven to drive. Examples of inversion driving include frame inversion driving, source line inversion driving, gate line inversion driving, dot inversion driving and the like.

The frame inversion driving is a driving method in which the polarity of the voltage applied to the liquid crystal element is inverted every one frame period. Note that one frame period corresponds to a period for displaying an image for one pixel, and there is no particular limitation on that period, but at least 1/60 seconds so that a person viewing the image does not feel flicker. It is preferable to set it as the following.

Furthermore, it is desirable to shorten the period and increase the frequency to reduce blurring of the image in the moving image. Preferably, the cycle is 1/120 second or less (frequency is 120 Hz or more). More preferably, the period is 1/180 second or less (the frequency is 180 Hz or more). When the frame frequency is thus improved, it is necessary to interpolate image data when the frame frequency does not match the data frame frequency of the original image. In this case, by interpolating image data using a motion vector, display can be performed at a high frame frequency. As described above, the movement of the image is displayed smoothly, and a display with less afterimage can be performed.

In source line inversion driving, the polarity of the voltage applied to the liquid crystal elements belonging to the pixels connected to the same signal line is inverted with respect to the liquid crystal elements belonging to the pixels connected to the adjacent signal line. This is a driving method for performing frame inversion on each pixel. On the other hand, in gate line inversion driving, the polarity of the voltage applied to the liquid crystal elements belonging to the pixels connected to the same scan line is
This is a driving method in which liquid crystal elements belonging to pixels connected to adjacent scanning lines are inverted, and frame inversion is further performed on each pixel. The dot inversion drive is a drive method for reversing the polarity of a voltage applied to a liquid crystal element between adjacent pixels, and is a drive method combining source line inversion drive and gate line inversion drive.

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

The common inversion drive is a drive method of changing the potential of the common electrode in synchronization with the inversion of the polarity applied to the liquid crystal element, and the common inversion drive is a potential required for an image signal written to the signal line. The width can be reduced. In this case, the common electrode 118 and the Cs line 119 (Cs lines Cs_1 to Cs_n in FIG. 11) are preferably electrically connected. The same signal is input to the common electrode 118 and the Cs line 119, which can be displayed more appropriately.

Next, FIG. 12 shows a configuration example of a pixel that can realize dot inversion driving. In FIG. 12, four pixels are extracted and described, and each pixel has the configuration shown in FIG. In the figure, signal lines 116_1 and 116_2 are connected to the signal line 116 in FIG.
_ 1, 117 _ 2 to scan line 117, Cs line 119 _ 1, 119 _2, 719 _ 1, 71
9_2 corresponds to the Cs line 119. Signals of different polarities are input to the signal lines 116_1 and 116_2. In addition to the polarity, even pixels belonging to the same row are different from adjacent pixels C
The s-line, that is, the Cs line 119_1, 719_2 or 119_1, 719_2 is used to supply a potential different from that of the adjacent pixel as shown in FIG. The dot inversion drive may be performed by driving as shown in FIG.

Note that the signal for displaying black in the case of normally black and the signal for displaying white in the case of normally white are | Vsig (0) | and the potential of the common electrode is Vcom.
Then, if a signal of positive polarity from the signal line is supplied to the pixel, Vcom or more and Vsig (above
0) It is sufficient if a potential not higher than + Vcom is supplied to the Cs line. On the other hand, when a signal of negative polarity is supplied to the pixel, a potential of −Vsig (0) + Vcom or more and Vcom or less may be supplied to the Cs line.

When a signal of positive polarity is supplied to the pixel, Vcom + α or more and Vsig (0) + V
If a potential lower than com and a negative signal are supplied to the pixel, −Vsig (0) + Vc
It is preferable that a potential of om or more and Vcom-α or less be supplied to the Cs line. Here, α is V
It is sig / 2. Furthermore, more preferably, when a positive polarity signal is supplied to the pixel, V
When the signal of negative polarity is supplied to the pixel, the potential of sig (0) + Vcom is -Vsig.
It is preferable that a potential of (0) + Vcom be supplied.

As described above, when the positive polarity signal is supplied to the pixel, the potential of the Cs line is Vsig (0
When the signal of the negative polarity is supplied, the voltage applied to the second liquid crystal element 122 can be increased by supplying + Vcom and the signal of the negative polarity, and the second liquid crystal can be further increased. Control of the element 122 can be facilitated.

When a signal of positive polarity is supplied to the pixel, the potential of the Cs line is set to Vsig (0) + Vco.
When the potential is higher than m, a voltage higher than Vsig (0) is always applied to the liquid crystal,
In the case of normally black, black can not be displayed, and in the case of normally white, white can not be displayed. Also, when a signal of negative polarity is supplied to the pixel, −Vsig (0) +
If a potential lower than Vcom is supplied to the Cs line, as in the case of a positive polarity signal, black can not be displayed in the case of normally black and white can be displayed in the case of normally white.

Note that in FIG. 13, the potential of Vcom is 0 V, and Cs in the case where a signal of positive polarity is supplied to the pixel.
The potential of the line is Vsig (0), and the potential of the line Cs when the signal of negative polarity is supplied to the pixel is -V
The case of sig (0) is described.

  The method of inversion driving is not limited to the above.

Although FIGS. 1 to 12 show the case where two liquid crystal elements are provided in one pixel, the number of liquid crystal elements included in the pixel is not particularly limited. FIG. 14 shows the case where three liquid crystal elements are included in one pixel. The pixel illustrated in FIG. 14 includes a fourth transistor 814, a third liquid crystal element 823, and a third storage capacitor 833 in addition to the pixel configuration illustrated in FIG. In FIG. 14, the pixel electrode of the third liquid crystal element 823 is connected to the signal line 116 through the second transistor 212 and the first switch 111. In addition, the third liquid crystal element 8
Assuming that the connection point between the 23 pixel electrodes and the second transistor 212 is a node 800, the node 800 is connected to the node 142 through the fourth transistor 814. Note that the gate electrode of the fourth transistor 814 is connected to the scan line 117 as in the case of the second transistor 212 and the third transistor 213. Further, the node 800 is connected to the Cs line 119 via the third storage capacitor 833. Thus, in FIG.
A unit 801 including a liquid crystal element 823 and a storage capacitor 833 is provided between the second transistor 212 and the node 142. Note that in the case where the number of liquid crystal elements included in a pixel is increased, for example, the number of units 801 may be increased. Of course, it is not limited to this.

In addition, one pixel may have a plurality of the pixel configurations described above. One configuration example of such a pixel is shown in FIG. The pixel shown in FIG. 15 has two sub-pixels 900a and 900b, and the gradation of one pixel is expressed using these sub-pixels. In FIG. 15, the pixel configuration shown in FIG. 4 is described for each of the sub-pixels. However, the signal lines 116 and the scanning lines 117 connected to the sub-pixels 900 a and 900 b are shared and used among the sub-pixels. Note that
Cs lines 119a and 119b in the figure correspond to the Cs line 119 in FIG. Each of the Cs lines 119 connected to the sub-pixels 900a and 900b, that is, the Cs lines 119a and 119b
By supplying different potentials, different voltages can be applied to liquid crystal elements belonging to respective sub-pixels. In this way, it is possible to further improve the viewing angle by utilizing the difference in the alignment of the liquid crystal in each sub-pixel.

Also, as shown in FIG. 15, the case where the signal line 116 and the scanning line 117 are used as common wiring between the sub-pixels is shown. However, as shown in FIG.
It may be shared between 000a and 1000b. Alternatively, as shown in FIG. 17, only the signal line 116 may be shared between the sub-pixels 1100a and 1100b, and the gradation of one pixel may be expressed using these sub-pixels. Note that the wiring shared and used among the sub-pixels is not limited to the above, and C
The s-line 119 may be used, or two or more wires may be shared as shown in FIG. The signal lines 116a and 116b in FIG. 16 or 17 correspond to the signal line 116 in FIG. 4, and the scanning lines 117a and 117b correspond to the scanning line 117 in FIG. 4 and the Cs lines 119a and 119b.
Corresponds to the Cs line 119 in FIG.

Although FIGS. 15 to 17 show the case where one pixel is configured by sub-pixels having the same configuration, the configuration may be different between the sub-pixels.

As described above, the viewing angle characteristics can be improved by the present invention. Furthermore, since it is the structure which can be made to drive without causing the fall of contrast, it becomes possible to provide a liquid crystal display device with a higher display quality.

In the present embodiment, the first switch 111 and the second switch 112 mainly shown in FIG.
And the third switch 113 are controlled at the same time, each switch may be controlled separately. For example, in addition to the scan line 117 shown in FIG. 2, other scan lines may be separately controlled. Alternatively, some of the plurality of switches may be controlled simultaneously, and the remaining switches may be separately controlled. Further, in the above, the resistor and the switch may be replaced by a capacitor.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of the present embodiment can be applied to, combined with, or replaced with the contents (or a part) described in the figure of another embodiment. Etc. can be done freely. Furthermore, in the drawings of the present embodiment, more parts can be configured by combining the parts of the other embodiments with respect to the respective parts.

Note that this embodiment is an example in the case of embodying the contents (may be a part) described in the other embodiments, an example in the case of slight modification, an example in the case of changing a part, an improvement An example of the case,
An example of the case described in detail, an example of the case of application, an example of the relevant part, and the like are shown. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or replaced with this embodiment.

Second Embodiment
In this embodiment, a configuration different from that of Embodiment 1 is shown in FIG. In Embodiment 1, the potential applied to the pixel electrodes of the first liquid crystal element and the second liquid crystal element is determined by the resistance division between the signal line and the Cs line, but the Cs line is not necessarily required. . An example is shown in this embodiment.

The pixel 1200 illustrated in FIG. 18 includes a switch 111, a transistor 212, and a transistor 2
13 includes a first liquid crystal element 121, a second liquid crystal element 122, a first storage capacitor 131, and a second storage capacitor 132. Note that the pixel 1200 is connected to the signal line 116, the scan line 117, the Cs line 119, and the potential supply line 1219. That is, the pixel 1200 is described in Embodiment 1.
In the pixel shown in FIG. 4, one electrode of the transistor 213 is not the Cs line 119,
It is configured to be connected to the potential supply line 1219. Of course, reference numerals denoting the same things are used in common between the drawings, and the explanation thereof is omitted. Note that four pixels 1200 are extracted and described in FIG.

Also in the pixel 1200 illustrated in FIG. 18, it is possible to appropriately select and use frame inversion driving, source line inversion driving, gate line inversion driving, and dot inversion driving. Note that the potential supply line 1219 may be supplied with a constant potential during one frame period, depending on the driving method. For example, one scan line selection period, that is, one floor of each pixel in a pixel belonging to a certain row. It may be changed every period in which the potential corresponding to the key is input.

Further, as shown in Embodiment 1, a transistor can be used as the switch 111 in FIG. 18, and each of the transistor 212 and the transistor 213 can be replaced with a switch and a resistor. In addition, the pixel 1200 in FIG. 18 can be combined with the matters described in Embodiment 1 as appropriate.

In addition, an image signal can be input to the potential supply line 1219 illustrated in FIG. 18, and the potential supply line 1219 and the signal line 116 can be reversed to function. As described above, by changing the wiring for inputting the potential according to the image signal, that is, the gradation of the pixel, one liquid crystal element, for example, the first liquid crystal element 121 is applied compared to the other, for example, the second liquid crystal element 122. Voltage can be prevented from constantly increasing. Thus, deterioration of the liquid crystal element can be delayed.

A display device having such a pixel is described with reference to FIG. The display device includes a signal line driver circuit 511, a signal line switching circuit 1300, a scan line driver circuit 512, and a pixel portion 51.
3 and switches the wiring for supplying the image signal using the signal line switching circuit 1300.
Note that the display device shown in FIG. 19 is provided with a signal line switching circuit 1300 in addition to the configuration of the display device shown in FIG. Note that the signal line switching circuit 1300 is provided in the pixel portion 513.
And a plurality of wirings 1316 and wirings 1319 arranged extending in the column direction, and scanning lines G1 to Gn and Cs lines Cs_1 to Cs_n arranged extending in the row direction from the scanning line driving circuit 512.
, And the plurality of pixels 1200 arranged in a matrix corresponding to the wiring 1316. Then, each pixel 1200 includes the wiring 1316, the wiring 1319, and the scanning line Gi (scanning lines G1 to
Any one of Gn) and Cs line Cs_i are connected. Note that the wiring 1316 and the wiring 1319 are connected to the signal line Sj (signal line S1 via the signal line switching circuit 1300).
.About.Sm) is connected to any one of the potential supply lines Sj_2. Of course, in the case where the wiring for supplying the image signal is only the signal line, the signal line switching circuit 1300
Is unnecessary.

The signal line switching circuit 1300 will be described with reference to FIG. Signal line switching circuit 1
Reference numeral 300 denotes m units 140 corresponding to the pixels 1200 in the column direction of the pixel portion.
0, an inverter 1401, a wire 1402, and a wire 1403 connected to the wire 1402 via the inverter 1401. Each unit 1400 includes a transistor 1404.
, The transistor 1405, the transistor 1406, and the transistor 1407;
402, a wire 1403, a signal line Sj, a potential supply line Sj_2, a wire 1316, a wire 1319
And connected. The signal line Sj is connected to the wiring 1316 via the transistor 1404 and the wiring 1319 via the transistor 1405, and the potential supply line Sj_2 is connected to the wiring 1319 via the transistor 1406 and the wiring 1316 via the transistor 1407.
And connected. Note that the transistor 1405 and the transistor 1407 have a wiring 140
The transistor 1404 and the transistor 1406 are controlled to be on / off by the wiring 1403 by the transistor 2.

A signal synchronized to one scanning line period or one frame period is input to the wiring 1402;
An inverted signal of the signal input to the wiring 1402 through the inverter 1401 is input to the wiring 1430. Therefore, when the transistor 1405 and the transistor 1407 are off, the transistor 1404 and the transistor 1406 are on, and when the transistor 1405 and the transistor 1407 are on, the transistor 1
The transistor 404 and the transistor 1406 are off. In this manner, which of the wiring 1316 and the wiring 1319 can be connected to the signal line Sj and the potential supply line Sj_2 can be selected. Note that a signal input to the wiring 1402 may be appropriately selected by a method of inversion driving.

Further, as shown in FIG. 21, the Cs line 119 may be substituted by the scanning line 117 in the previous row. Here, the case where the Cs line 119 and the scanning line 117 in the previous row are shared is described.
It is not particularly limited as long as it can supply an arbitrary constant potential to the second electrodes of the first storage capacitor 131 and the second storage capacitor 132 as well as the Cs line 119. Note that during one frame period, the first
It is preferable that the second electrode of the second storage capacitor 132 and the second storage capacitor
As shown in FIG. 21, it is possible to use it because it does not greatly affect the alignment of the liquid crystal included in the first liquid crystal element 121 and the second liquid crystal element 122 if immediately before moving to the next frame period. Thus, by sharing the wiring with the previous row, the number of wirings provided in one pixel can be reduced, and the aperture ratio can be improved.

Also in the pixel configuration as described above, the gray scale represented by the pixel is determined by the orientation of the liquid crystal of each of the first liquid crystal element 121 and the second liquid crystal element 122 in the pixel, as in Embodiment 1. Therefore, the viewing angle can be improved. Furthermore, since it is the structure which can be made to drive without causing the fall of contrast, it becomes possible to provide a liquid crystal display device with a higher display quality.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of the present embodiment can be applied to, combined with, or replaced with the contents (or a part) described in the figure of another embodiment. Etc. can be done freely. Furthermore, in the drawings of the present embodiment, more parts can be configured by combining the parts of the other embodiments with respect to the respective parts.

Note that this embodiment is an example in the case of embodying the contents (may be a part) described in the other embodiments, an example in the case of slight modification, an example in the case of changing a part, an improvement An example of the case,
An example of the case described in detail, an example of the case of application, an example of the relevant part, and the like are shown. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or replaced with this embodiment.

Third Embodiment
In this embodiment, an example of a pixel configuration which is different from those in Embodiments 1 and 2 will be described. Figure 2
The pixel shown in 2 includes the switch 111, the transistor 212, the transistor 213, the first liquid crystal element 121, the second liquid crystal element 122, the first holding capacitance 131, the second holding capacitance 132, and the third holding capacitance 1601. Have. Note that the pixel illustrated in FIG. 22 is connected to the signal line 116, the scan line 117, and the Cs line 119, and between the node 142 and one electrode of the transistor 213 in the pixel in FIG. 4 described in Embodiment 1. The third storage capacitor 1601 is provided on the The same reference numerals as in FIG. 4 are used in common between the drawings, and the description thereof is omitted.

The pixel shown in FIG. 22 can also be operated in the same manner as the pixel shown in FIG. However, by providing the third storage capacitor 1601, it takes time to reach the potential according to the gradation to be supplied to the pixel electrode of the second liquid crystal element 122. Therefore, the first liquid crystal element 1
The viewing angle can be further improved by intentionally delaying the response of the liquid crystal of the second liquid crystal element 122 applied with a lower voltage than the voltage of the second liquid crystal element 122. Also in this case, the gray scale represented by the pixel is determined by the orientation of the liquid crystal of each of the first liquid crystal element 121 and the second liquid crystal element 122 in the pixel, so the potential supplied from the signal line 116 is Determine in consideration of

In addition, as shown in FIG. 23, the third storage capacitor 1701 includes the transistor 212 and the node 14.
It may be provided between the two. Also in FIG. 23, the same operation as the pixel shown in FIG. 4 can be performed. Similar to the pixel shown in FIG. 22, it takes time for the pixel electrode of the second liquid crystal element 122 to reach a potential corresponding to the gradation to be supplied. This can be used to further improve the viewing angle. In this case, taking into consideration that the voltage applied to the second liquid crystal element 122 is determined by capacitive division with the third storage capacitor 1701, the signal line 1
It is necessary to determine the potential supplied from 16.

Also in the pixel configuration as described above, the gray scale represented by the pixel is determined by the orientation of the liquid crystal of each of the first liquid crystal element 121 and the second liquid crystal element 122 in the pixel, as in Embodiment 1. Therefore, the viewing angle can be improved. Furthermore, since it is the structure which can be made to drive without causing the fall of contrast, it becomes possible to provide a liquid crystal display device with a higher display quality.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of the present embodiment can be applied to, combined with, or replaced with the contents (or a part) described in the figure of another embodiment. Etc. can be done freely. Furthermore, in the drawings of the present embodiment, more parts can be configured by combining the parts of the other embodiments with respect to the respective parts.

Note that this embodiment is an example in the case of embodying the contents (may be a part) described in the other embodiments, an example in the case of slight modification, an example in the case of changing a part, an improvement An example of the case,
An example of the case described in detail, an example of the case of application, an example of the relevant part, and the like are shown. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or replaced with this embodiment.

Embodiment 4
In this embodiment, an example of a pixel configuration which is different from those in Embodiments 1 to 3 will be described. Figure 2
The pixel shown in 4 includes a switch 111, a transistor 212, a transistor 213, a transistor 1804, a first liquid crystal element 121, a second liquid crystal element 122, a first storage capacitor 131, and the like.
The second storage capacitor 132 and the third storage capacitor 1801 are provided. Note that the pixel shown in FIG. 24 is connected to the signal line 116, the scan line 117, and the Cs line 119, and a transistor 1804 and a third storage capacitor 1801 are further provided in the pixel of FIG. 4 shown in Embodiment 1. The configuration is The same reference numerals as in FIG. 4 are used in common between the drawings, and the description thereof is omitted.

The third storage capacitor 1801 is a node where the connection point between the node 142 and the wiring to which the first electrode of the second storage capacitor 132 and the pixel electrode of the second liquid crystal element 122 are connected is It is provided between the node 1802 and the pixel electrode of the second liquid crystal element 122. The transistor 1804 is provided between the node 1803 and the signal line 116, where the connection point between the third storage capacitor 1801 and the pixel electrode of the second liquid crystal element 122 is a node 1803. That is, the node 1803 is connected to the signal line 116 through the transistor 1804. Like the switch 111, the transistor 212, and the transistor 213, the transistor 1804 is turned on and off by a signal input to the scan line 117.

The pixel shown in FIG. 24 can also be operated in the same manner as the pixel shown in FIG. Note that in the pixel shown in FIG. 24, the pixel electrode of the first liquid crystal element 121 and the second liquid crystal element 122 has a potential corresponding to the gradation of the pixel simultaneously from the signal line 116 through the switch 111 and the transistor 1804. Supplied. Therefore, a potential corresponding to the gray level of a pixel can be supplied to the pixel electrode of each liquid crystal element more quickly. Therefore, it is effective in high speed operation and the like. Note that the on resistance of the transistor 1804 is preferably larger than the on resistance of the switch 111 or the transistor 212. Note that W4 / L4 is preferably small, where W4 is the channel width of the transistor 1804 and L4 is the channel length. In addition, in the pixel illustrated in FIG. 24, the gray scale represented by the pixel is determined by the orientation of liquid crystal included in each of the first liquid crystal element 121 and the second liquid crystal element 122 in the pixel, so the viewing angle is improved. be able to.

As described above, the viewing angle characteristics can be improved by the present invention. Furthermore, since it is the structure which can be made to drive without causing the fall of contrast, it becomes possible to provide a liquid crystal display device with a higher display quality.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of the present embodiment can be applied to, combined with, or replaced with the contents (or a part) described in the figure of another embodiment. Etc. can be done freely. Furthermore, in the drawings of the present embodiment, more parts can be configured by combining the parts of the other embodiments with respect to the respective parts.

Note that this embodiment is an example in the case of embodying the contents (may be a part) described in the other embodiments, an example in the case of slight modification, an example in the case of changing a part, an improvement An example of the case,
An example of the case described in detail, an example of the case of application, an example of the relevant part, and the like are shown. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or replaced with this embodiment.

Fifth Embodiment
In this embodiment, an example of a pixel configuration which is different from those in Embodiments 1 to 4 will be described. Figure 25.
The pixel illustrated in the drawing includes the switch 111, the transistor 212, the transistor 213, the first liquid crystal element 121, the second liquid crystal element 122, the first holding capacitor 131, the second holding capacitor 132, and the third holding capacitor 1901. . Note that the pixel shown in FIG.
The third storage capacitor 1901 is further provided in the pixel of FIG. 4 shown in the first embodiment. The same reference numerals as in FIG. 4 are used in common between the drawings, and the description thereof is omitted.

Assuming that the connection point between the node 142 and the wiring to which the first electrode of the second storage capacitor 132 and the pixel electrode of the second liquid crystal element 122 are connected is the node 1902. It is provided between the node 1902 and the pixel electrode of the second liquid crystal element 122.

The pixel shown in FIG. 25 can also be operated in the same manner as the pixel shown in FIG. However, by providing the third storage capacitor 1901, it takes time to reach a potential corresponding to the gradation to be supplied to the pixel electrode of the second liquid crystal element 122. This can be used to further improve the viewing angle. In addition, since the voltage applied to the second liquid crystal element 122 is determined by the capacitance division with the third storage capacitor 1901, it is effective when it is desired to apply a small voltage to the second liquid crystal element 122 or the like.

Also in the pixel according to the present embodiment, the gradation represented by the pixel is determined by the orientation of the liquid crystal of each of the first liquid crystal element 121 and the second liquid crystal element 122 in the pixel, so the viewing angle is improved. be able to.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of the present embodiment can be applied to, combined with, or replaced with the contents (or a part) described in the figure of another embodiment. Etc. can be done freely. Furthermore, in the drawings of the present embodiment, more parts can be configured by combining the parts of the other embodiments with respect to the respective parts.

Note that this embodiment is an example in the case of embodying the contents (may be a part) described in the other embodiments, an example in the case of slight modification, an example in the case of changing a part, an improvement An example of the case,
An example of the case described in detail, an example of the case of application, an example of the relevant part, and the like are shown. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or replaced with this embodiment.

Sixth Embodiment
In this embodiment mode, a pixel structure of a display device is described. In particular, the pixel structure of the liquid crystal display device is described.

A pixel structure in the case where each liquid crystal mode and a transistor are combined will be described with reference to a cross-sectional view of the pixel.

Note that as the transistor, a thin film transistor (TFT) having a non-single-crystal semiconductor layer typified by amorphous silicon, polycrystalline silicon, microcrystalline (also referred to as microcrystalline or semi-amorphous) silicon, or the like can be used. In addition, as a structure of the transistor, a top gate type, a bottom gate type, or the like can be used. Note that as the bottom gate transistor, a channel etch type or a channel protective type can be used.

FIG. 28 is an example of a cross-sectional view of a pixel in the case where a TN method and a transistor are combined.
The features of the pixel structure shown in FIG. 28 will be described.

The liquid crystal molecules 2018 shown in FIG. 28 are elongated molecules having a major axis and a minor axis. here,
The orientation of the liquid crystal molecule 2018 is expressed by the length of the liquid crystal molecule described in the drawing. That is,
The direction of the long axis of the liquid crystal molecule 2018 is parallel to the paper surface (cross-sectional direction shown in FIG. 28), and the direction of the long axis of the liquid crystal molecule 2018 represented short is normal to the paper surface It is assumed that it is near. The liquid crystal molecules 2018 shown in FIG.
The directions of the major axes of the liquid crystal molecules in the near one and the ones near the second substrate 2016 differ by 90 degrees, and the directions of the major axes of the liquid crystal molecules 2018 located in the middle between these substrates make these smooth. It is oriented to connect. That is, the liquid crystal molecules 2018 shown in FIG.
Between the first substrate 2001 and the second substrate 2016 in a 90.degree. Twist orientation.

Note that a bottom gate transistor using an amorphous semiconductor is used as the transistor. In the case of using a transistor including an amorphous semiconductor, a liquid crystal display device can be manufactured inexpensively using a substrate with a large area.

The liquid crystal display device has a main part that displays an image called a liquid crystal panel. The liquid crystal panel is made by bonding two processed substrates with a gap of several micrometers.
It is manufactured by injecting a liquid crystal material between sheets of substrates. That is, the liquid crystal has a first substrate and a second substrate.
It is the structure clamped by two board | substrates of board | substrates. In FIG. 28, the liquid crystal 201 is
1 is sandwiched between the first substrate 2001 and the second substrate 2016. First substrate 200
In FIG. 1, a transistor and a pixel electrode are formed, and a light shielding film 201 is formed on the second substrate 2016.
4, the color filter 2015, the fourth conductive layer 2013, the spacer 2017, and the second alignment film 2012 are formed.

By providing the light shielding film 2014, a display device with little light leakage can be obtained when displaying black. Note that the light shielding film 2014 may not be particularly formed on the second substrate 2016. When the light shielding film 2014 is not formed, the number of steps can be reduced, so that the manufacturing cost can be reduced and the yield can be improved.

In addition, the color filter 2015 may not be formed on the second substrate 2016. Even when the color filter 2015 is not formed, the number of steps can be reduced as in the case of the light shielding film, so that the manufacturing cost can be reduced and the yield can be improved. However,
In the case where the color filter 2015 is not formed, a display device capable of performing color display by field sequential driving can be obtained.

Also, spherical spacers may be dispersed instead of the spacers 2017. In the case of dispersing spherical spacers, the number of steps is reduced, and thus the manufacturing cost can be reduced. In addition, the yield can be improved. On the other hand, in the case of forming the spacer 2017, since the position of the spacer does not vary, the distance between the two substrates can be more easily made constant, and a display device with less display unevenness can be obtained.

Next, processing to be performed on the first substrate 2001 will be described.

First, the first insulating film 2002 is formed over the first substrate 2001 by a sputtering method, a printing method, a coating method, or the like. The first insulating film 2002 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the characteristics of the transistor. Note that in the case where quartz is used as the substrate 2001, the first insulating film 2002 may not be formed.

Next, a first conductive layer 2003 is formed over the first insulating film 2002 by photolithography, a laser direct writing method, an inkjet method, or the like.

Next, a second insulating film 2004 is formed on the entire surface by a sputtering method, a printing method, a coating method, or the like. The second insulating film 2004 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the characteristics of the transistor.

Next, a first semiconductor layer 2005 and a second semiconductor layer 2006 are formed. Note that the first semiconductor layer 2005 and the second semiconductor layer 2006 are continuously formed, and their shapes are processed at the same time.

Next, a second conductive layer 2007 is formed by a photolithography method, a laser direct writing method, an inkjet method, or the like. Note that dry etching is preferably used as an etching method which is performed when the shape of the second conductive layer 2007 is processed. Note that for the second conductive layer 2007, a material having transparency may be used, or a material having reflectivity may be used.

Next, a channel region of the transistor is formed. An example of the process will be described. The second semiconductor layer 2006 is etched using the second conductive layer 2007 as a mask. Also,
The mask may be etched using a mask for processing the shape of the second conductive layer 2007. Then, a portion of the first semiconductor layer 2005 from which the second semiconductor layer 2006 is removed becomes a channel region of the transistor. By forming the channel region in this manner, the number of masks can be reduced, and the manufacturing cost can be reduced.

Next, a third insulating film 2008 is formed, and a contact hole is selectively formed in the third insulating film 2008. Note that a contact hole may be formed in the second insulating film 2004 at the same time as the contact hole is formed in the third insulating film 2008. Note that the surface of the third insulating film 2008 is preferably as flat as possible. This is because the unevenness of the surface in contact with the liquid crystal, that is, the surface of the third insulating film 2008 affects the alignment of liquid crystal molecules.

Next, a third conductive layer 2009 is formed by a photolithography method, a laser direct writing method, an inkjet method, or the like.

Next, a first alignment film 2010 is formed. Note that after the first alignment film 2010 is formed, rubbing may be performed to control the alignment of liquid crystal molecules.

The first substrate 2001 manufactured as described above, the light shielding film 2014, the color filter 2015
, The fourth conductive layer 2013, the spacer 2017, and the second alignment film 2012 are formed.
And a substrate 2016 with a gap of several micrometers are attached by a sealing material. Then, a liquid crystal material is injected between the two substrates. Note that in the TN method, the fourth conductive layer 2013 is formed over the entire surface of the second substrate 2016.

FIG. 29A shows the MVA (Multi-domain Vertical Alignm).
3 is an example of a cross-sectional view of a pixel in the case where the (ent) method and a transistor are combined. Figure 29.
The viewing angle can be further increased by applying the pixel structure shown in (A) to the liquid crystal display device of the present invention.

Features of the pixel structure of the MVA liquid crystal panel will be described using the pixel structure shown in FIG. The liquid crystal molecules 2118 shown in FIG. 29A are the liquid crystal molecules 201 shown in FIG.
Like 8, it is an elongated molecule with a major axis and a minor axis. Therefore, also in FIG. 29A, the direction of the liquid crystal molecule 2118 is expressed by the length of the liquid crystal molecule indicated in the drawing. In other words, Figure 2
The liquid crystal molecules 2118 shown in 9 (A) are aligned such that the direction of the major axis is normal to the alignment film. In addition, liquid crystal molecules 2118 in a portion where the alignment control protrusions 2119 are present are radially aligned about the alignment control protrusions 2119. By this state, a liquid crystal display device having a large viewing angle can be obtained.

Note that a bottom gate transistor using an amorphous semiconductor is used as the transistor. In the case of using a transistor including an amorphous semiconductor, a liquid crystal display device can be manufactured inexpensively using a substrate with a large area.

In FIG. 29A, two substrates which sandwich the liquid crystal 2111 correspond to the first substrate 2101 and the second substrate 2116. Note that a transistor and a pixel electrode are formed over the first substrate 2101, and a light shielding film 2114, a color filter 2115, and the like are formed over the second substrate 2116.
A fourth conductive layer 2113, a spacer 2117, a second alignment film 2112, and an alignment control protrusion 2119 are formed.

By providing the light shielding film 2114, a display device with less light leakage can be obtained when displaying black. Note that the light shielding film 2114 may not be particularly formed on the second substrate 2116. When the light shielding film 2114 is not formed, the number of steps can be reduced, so that the manufacturing cost can be reduced and the yield can be improved.

In addition, the color filter 2115 may not be formed on the second substrate 2116. Even when the color filter 2115 is not formed, the number of steps can be reduced as in the case of the light-shielding film, so that the manufacturing cost can be reduced and the yield can be improved. However,
In the case where the color filter 2115 is not formed, a display device capable of performing color display by field sequential driving can be obtained.

Also, spherical spacers may be dispersed instead of the spacers 2117. In the case of dispersing spherical spacers, the number of steps is reduced, and thus the manufacturing cost can be reduced. In addition, the yield can be improved. On the other hand, in the case of forming the spacer 2117, since the position of the spacer does not vary, the distance between the two substrates can be more easily made constant, and a display device with few display unevenness can be obtained.

A process to be performed on the first substrate 2101 will be described.

First, a first insulating film 2102 is formed over a first substrate 2101 by a sputtering method, a printing method, a coating method, or the like. The first insulating film 2102 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the characteristics of the transistor. However, in the case where quartz is used as the substrate 2101, the first insulating film 2102 may not be formed.

Next, a first conductive layer 2103 is formed over the first insulating film 2102 by photolithography, a laser direct writing method, an inkjet method, or the like.

Next, a second insulating film 2104 is formed on the entire surface by a sputtering method, a printing method, a coating method, or the like. The second insulating film 2104 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the characteristics of the transistor.

Next, a first semiconductor layer 2105 and a second semiconductor layer 2106 are formed. Note that the first semiconductor layer 2105 and the second semiconductor layer 2106 are continuously formed, and their shapes are processed at the same time.

Next, a second conductive layer 2107 is formed by a photolithography method, a laser direct writing method, an inkjet method, or the like. Note that dry etching is preferably used as an etching method which is performed when the shape of the second conductive layer 2107 is processed. Note that as the second conductive layer 2107, a transparent material may be used, or a reflective material may be used.

Next, a channel region of the transistor is formed. An example of the process will be described. The second semiconductor layer 225 is etched using the second conductive layer 2107 as a mask. Alternatively, the mask may be etched using a mask for processing the shape of the second conductive layer 2107. Then, a portion of the first semiconductor layer 2105 from which the second semiconductor layer 2106 is removed becomes a channel region of the transistor. By forming the channel region in this manner, the number of masks can be reduced, and the manufacturing cost can be reduced.

Next, a third insulating film 2108 is formed, and a contact hole is selectively formed in the third insulating film 2108. Note that a contact hole may be formed in the second insulating film 2104 at the same time as the contact hole is formed in the third insulating film 2108.

Next, a third conductive layer 2109 is formed by a photolithography method, a laser direct writing method, an inkjet method, or the like.

Next, a first alignment film 2110 is formed. Note that after the first alignment film 2110 is formed, rubbing may be performed to control the alignment of liquid crystal molecules.

The first substrate 2101 manufactured as described above, the light shielding film 2114, and the color filter 2115
, The fourth conductive layer 2113, the spacer 2117, and the second alignment film 2112.
And the substrate 2116 are attached by a sealant with a gap of several micrometers. Then, a liquid crystal material is injected between the two substrates.

Note that in the MVA method, the fourth conductive layer 2113 is formed on the entire surface of the second substrate 2116. In addition, an alignment control protrusion 2119 is formed in contact with the fourth conductive layer 2113. The shape of the orientation control projection 2119 is preferably a shape having a smooth curved surface. By doing this, the alignment failure of the liquid crystal molecules 2118 due to the alignment control protrusions 2119 is reduced. Further, since disconnection of the alignment film formed on the alignment control projections 2119 can be prevented, defects in the alignment film due to the disconnection can also be reduced.

FIG. 29 (B) shows PVA (Paterned Vertical Alignment).
It is an example of sectional drawing of the pixel at the time of combining a system and a transistor. The viewing angle can be further increased by applying the pixel structure shown in FIG. 29B to the liquid crystal display device of the present invention.

The features of the pixel structure shown in FIG. 29B will be described. Liquid crystal molecules 2 shown in FIG.
Similarly to the liquid crystal molecules 2018 shown in FIG. 28, the liquid crystal molecules 2 148 are also shown in FIG.
The orientation of 148 is expressed by the length of the liquid crystal molecule indicated in the figure. Therefore, as shown in FIG.
The liquid crystal molecules 2148 shown in the above are aligned such that the direction of the major axis is normal to the alignment film. In addition, liquid crystal molecules 2148 present around the electrode notch 2149 where the fourth conductive layer 2143 is not provided are radially aligned around the boundary between the electrode notch 2149 and the fourth conductive layer 2143. By this state, a liquid crystal display device having a large viewing angle can be obtained.

Note that a bottom gate transistor using an amorphous semiconductor is used as the transistor. In the case of using a transistor including an amorphous semiconductor, a liquid crystal display device can be manufactured inexpensively using a substrate with a large area.

In FIG. 29B, two substrates which sandwich the liquid crystal 2141 correspond to the first substrate 2131 and the second substrate 2146. Note that a transistor and a pixel electrode are formed over the first substrate 2131, and a light shielding film 2144, a color filter 2145, and the like are formed over the second substrate 2146.
A fourth conductive layer 2143, a spacer 2147, and a second alignment film 2142 are formed.

By providing the light shielding film 2144, a display device with little light leakage can be obtained when displaying black. Note that the light shielding film 2144 may not be particularly formed on the second substrate 2146. When the light shielding film 2144 is not formed, the number of steps can be reduced, so that the manufacturing cost can be reduced and the yield can be improved.

In addition, the color filter 2145 may not be formed on the second substrate 2146. Even when the color filter 2145 is not formed, the number of processes can be reduced as in the case of the light shielding film, so that the manufacturing cost can be reduced and the yield can be improved. However,
In the case where the color filter 2145 is not formed, a display device capable of performing color display by field sequential driving can be obtained.

Also, spherical spacers may be dispersed instead of the spacers 2147. In the case of dispersing spherical spacers, the number of steps is reduced, and thus the manufacturing cost can be reduced. In addition, the yield can be improved. On the other hand, in the case of forming the spacer 2147, since the position of the spacer does not vary, the distance between the two substrates can be more easily made constant, and a display device with less display unevenness can be obtained.

A process to be performed on the first substrate 2131 will be described.

First, the first insulating film 2132 is formed over the first substrate 2131 by a sputtering method, a printing method, a coating method, or the like. The first insulating film 2132 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the characteristics of the transistor. However,
In the case where quartz is used as the substrate 2131, the first insulating film 2132 may not be formed.

Next, a first conductive layer 2133 is formed over the first insulating film 2132 by photolithography, a laser direct writing method, an inkjet method, or the like.

Next, a second insulating film 2134 is formed on the entire surface by a sputtering method, a printing method, a coating method, or the like. The second insulating film 2134 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the characteristics of the transistor.

Next, a first semiconductor layer 2135 and a second semiconductor layer 2136 are formed. Note that the first semiconductor layer 2135 and the second semiconductor layer 2136 are continuously formed, and their shapes are processed at the same time.

Next, a second conductive layer 2137 is formed by a photolithography method, a laser direct writing method, an inkjet method, or the like. Note that dry etching is preferably used as an etching method which is performed when the shape of the second conductive layer 2137 is processed. Note that as the second conductive layer 2137, a transparent material may be used, or a reflective material may be used.

Next, a channel region of the transistor is formed. An example of the process will be described. The second semiconductor layer 2136 is etched using the second conductive layer 2137 as a mask. Also,
The mask may be etched using a mask for processing the shape of the second conductive layer 2137. Then, a portion of the first semiconductor layer 2135 from which the second semiconductor layer 2136 is removed becomes a channel region of the transistor. By forming the channel region in this manner, the number of masks can be reduced, and the manufacturing cost can be reduced.

Next, a third insulating film 2138 is formed, and a contact hole is selectively formed in the third insulating film 2138. Note that a contact hole may be formed in the second insulating film 2134 at the same time as the contact hole is formed in the third insulating film 2138.

Next, a third conductive layer 2139 is formed by a photolithography method, a laser direct writing method, an inkjet method, or the like.

Next, a first alignment film 2140 is formed. Note that after the first alignment film 2140 is formed, rubbing may be performed to control the alignment of liquid crystal molecules.

The first substrate 2131 manufactured as described above, the light shielding film 2144, and the color filter 2145
The fourth conductive layer 2143, the spacer 2147, and the second substrate 2146 on which the second alignment film 2142 is manufactured are attached by a sealant with a gap of several micrometers. Then, a liquid crystal material is injected between the two substrates.

In the PVA method, the fourth conductive layer 2143 is patterned to form an electrode notch 2149. The shape of the electrode notch 2149 is not particularly limited, but it is preferable that the shape is a combination of a plurality of rectangles having different directions. By doing this,
Since a plurality of regions with different orientations can be formed, a liquid crystal display device with a wide viewing angle can be obtained. The shape of the fourth conductive layer 2143 at the boundary between the electrode notch portion 2149 and the fourth conductive layer 2143 preferably has a smooth slope with respect to the bottom. By this, the alignment failure of the liquid crystal molecules 2148 in the vicinity of the slope is reduced. Further, since disconnection of the alignment film formed on the fourth conductive layer 2143 can be prevented, defects in the alignment film due to the disconnection can also be reduced.

FIG. 30A is an example of a cross-sectional view of a pixel in the case where an IPS (In-Plane-Switching) method and a transistor are combined. The viewing angle can be further increased by applying the pixel structure shown in FIG. 30A to the liquid crystal display device of the present invention.

The features of the pixel structure shown in FIG. 30A will be described. Liquid crystal molecules 2 shown in FIG.
Similarly to the liquid crystal molecules 2018 shown in FIG. 28, 248 are elongated molecules having a major axis and a minor axis. Therefore, also in FIG. 30A, the direction of the liquid crystal molecule 2218 is expressed by the length of the liquid crystal molecule indicated in the drawing. That is, the liquid crystal molecules 2218 shown in FIG. 30A are aligned such that the direction of the major axis is always horizontal to the substrate. Figure 30 (A)
Liquid crystal molecules 2 in a state in which no electric field is generated in the region where the liquid
Although an orientation of H.218 is shown, when an electric field is applied to the liquid crystal molecules 2218, the orientation of the major axis always rotates in the horizontal plane while maintaining the orientation horizontal to the substrate. By this state, a liquid crystal display device having a large viewing angle can be obtained.

Note that a bottom gate transistor using an amorphous semiconductor is used as the transistor. In the case of using a transistor including an amorphous semiconductor, a liquid crystal display device can be manufactured inexpensively using a substrate with a large area.

In FIG. 30A, two substrates which sandwich the liquid crystal 2211 correspond to the first substrate 2201 and the second substrate 2216. Note that a transistor and a pixel electrode are formed over the first substrate 2201, and a light shielding film 2214 and a color filter 2215 are formed over the second substrate 2216.
A spacer 2217 and a second alignment film 2212 are formed.

By providing the light shielding film 2214, a display device with less light leakage can be obtained when displaying black. Note that the light shielding film 2214 may not be particularly formed on the second substrate 2216. When the light shielding film 2214 is not formed, the number of steps can be reduced, so that the manufacturing cost can be reduced and the yield can be improved.

In addition, the color filter 2215 may not be formed on the second substrate 2216. Even when the color filter 2215 is not formed, the number of steps can be reduced as in the case of the light-shielding film, so that the manufacturing cost can be reduced and the yield can be improved. However,
In the case where the color filter 2215 is not formed, a display device capable of performing color display by field sequential driving can be obtained.

Also, spherical spacers may be dispersed instead of the spacers 2217. In the case of dispersing spherical spacers, the number of steps is reduced, and thus the manufacturing cost can be reduced. In addition, the yield can be improved. On the other hand, in the case where the spacer 2217 is formed, since the position of the spacer does not vary, the distance between the two substrates can be more easily fixed and a display device with few display unevenness can be obtained.

A process to be performed on the first substrate 2201 will be described.

First, the first insulating film 2202 is formed over the first substrate 2201 by a sputtering method, a printing method, a coating method, or the like. The first insulating film 2202 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the characteristics of the transistor. However, in the case where quartz is used as the substrate 2201, the first insulating film 2202 may not be formed.

Next, a first conductive layer 2203 is formed over the first insulating film 2202 by photolithography, a laser direct writing method, an inkjet method, or the like.

Next, a second insulating film 2204 is formed on the entire surface by a sputtering method, a printing method, a coating method, or the like. The second insulating film 2204 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the characteristics of the transistor.

Next, a first semiconductor layer 2205 and a second semiconductor layer 2206 are formed. Note that the first semiconductor layer 2205 and the second semiconductor layer 2206 are continuously formed, and their shapes are processed at the same time.

Next, a second conductive layer 2207 is formed by a photolithography method, a laser direct writing method, an inkjet method, or the like. Note that dry etching is preferably used as an etching method which is performed when the shape of the second conductive layer 2207 is processed. Note that as the second conductive layer 2207, a material having transparency or a material having reflectivity may be used.

Next, a channel region of the transistor is formed. An example of the process will be described. The second semiconductor layer 2206 is etched using the second conductive layer 2207 as a mask. Also,
The mask may be etched using a mask for processing the shape of the second conductive layer 2207. Then, a portion of the first semiconductor layer 2205 from which the second semiconductor layer 2206 is removed becomes a channel region of the transistor. By forming the channel region in this manner, the number of masks can be reduced, and the manufacturing cost can be reduced.

Next, a third insulating film 2208 is formed, and a contact hole is selectively formed in the third insulating film 2208. Note that a contact hole may be formed in the second insulating film 2204 at the same time as the contact hole is formed in the third insulating film 2208.

Next, a third conductive layer 2209 is formed by photolithography, a laser direct writing method, an inkjet method, or the like. Here, the shape of the third conductive layer 2209 is a shape of two comb teeth which are engaged with each other. One comb-like electrode is electrically connected to one of the source electrode and the drain electrode of the transistor, and the other comb-like electrode is electrically connected to the common electrode. By this, a lateral electric field can be effectively applied to the liquid crystal molecules 2218.

Next, a first alignment film 2210 is formed. Note that after the first alignment film 2210 is formed, rubbing may be performed to control the alignment of liquid crystal molecules.

The first substrate 2201 manufactured as described above, the light shielding film 2214, and the color filter 2215
The spacer 2217 and the second substrate 2216 on which the second alignment film 2212 is manufactured are attached by a sealant with a gap of several micrometers. Then, a liquid crystal material is injected between the two substrates.

FIG. 30B is an example of a cross-sectional view of a pixel in the case where a FFS (Fringe Field Switching) method and a transistor are combined. The viewing angle can be further increased by applying the pixel structure shown in FIG. 30B to the liquid crystal display device of the present invention.

The features of the pixel structure shown in FIG. 30B will be described. Liquid crystal molecules 2 shown in FIG.
Similarly to the liquid crystal molecules 2018 shown in FIG. 28 and FIG.
The direction of 48 is expressed by the length of the liquid crystal molecule described in the figure. Therefore, as shown in FIG.
The liquid crystal molecules 2248 shown in are aligned such that the direction of the major axis is always horizontal to the substrate. FIG. 30B shows the alignment of liquid crystal molecules 2248 in a state where no electric field is generated in the region where the liquid crystal 2241 is present, but when an electric field is applied to the liquid crystal molecules 2248, the direction of the major axis Always rotate in the horizontal plane while maintaining the horizontal direction with respect to the substrate. By this state, a liquid crystal display device having a large viewing angle can be obtained.

Note that a bottom gate transistor using an amorphous semiconductor is used as the transistor. In the case of using a transistor including an amorphous semiconductor, a liquid crystal display device can be manufactured inexpensively using a substrate with a large area.

In FIG. 30B, two substrates holding the liquid crystal 2241 correspond to the first substrate 2231 and the second substrate 2246. Note that a transistor and a pixel electrode are formed over the first substrate 2241, and a light shielding film 2244, a color filter 2245, and the like are formed over the second substrate 2246.
A spacer 2247 and a second alignment film 2242 are formed.

By providing the light shielding film 2244, a display device with little light leakage can be obtained when displaying black. Note that the light shielding film 2244 may not be formed on the second substrate 2246 in particular. When the light shielding film 2244 is not formed, the number of steps can be reduced, so that the manufacturing cost can be reduced and the yield can be improved.

In addition, the color filter 2245 may not be formed on the second substrate 2246. Even when the color filter 2245 is not formed, the number of steps can be reduced as in the case of the light-shielding film, so that the manufacturing cost can be reduced and the yield can be improved. However,
In the case where the color filter 2245 is not formed, a display device capable of performing color display by field sequential driving can be obtained.

Also, spherical spacers may be dispersed instead of the spacers 2247. In the case of dispersing spherical spacers, the number of steps is reduced, and thus the manufacturing cost can be reduced. In addition, the yield can be improved. On the other hand, in the case of forming the spacer 2247, since the position of the spacer does not vary, the distance between the two substrates can be more easily made constant, and a display device with less display unevenness can be obtained.

The processing applied to the first substrate 2231 will be described.

First, the first insulating film 2232 is formed over the first substrate 2231 by a sputtering method, a printing method, a coating method, or the like. The first insulating film 2232 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the characteristics of the transistor. However,
In the case where quartz is used as the substrate 2231, the first insulating film 2232 may not be formed.

Next, a first conductive layer 2233 is formed over the first insulating film 2232 by photolithography, a laser direct writing method, an inkjet method, or the like.

Next, a second insulating film 2234 is formed on the entire surface by a sputtering method, a printing method, a coating method, or the like. The second insulating film 2234 has a function of preventing impurities from the substrate from affecting the semiconductor layer and changing the characteristics of the transistor.

Next, a first semiconductor layer 2235 and a second semiconductor layer 2236 are formed. Note that the first semiconductor layer 2235 and the second semiconductor layer 2236 are continuously formed, and their shapes are processed at the same time.

Next, a second conductive layer 2237 is formed by a photolithography method, a laser direct writing method, an inkjet method, or the like. Note that dry etching is preferably used as an etching method which is performed when the shape of the second conductive layer 2237 is processed. Note that as the second conductive layer 2237, a material having transparency may be used, or a material having reflectivity may be used.

Next, a channel region of the transistor is formed. An example of the process will be described. The second semiconductor layer 2236 is etched using the second conductive layer 2237 as a mask. Also,
The mask may be etched using a mask for processing the shape of the second conductive layer 2237. Then, a portion of the first semiconductor layer 2235 from which the second semiconductor layer 2236 is removed becomes a channel region of the transistor. By forming the channel region in this manner, the number of masks can be reduced, and the manufacturing cost can be reduced.

Next, a third insulating film 2238 is formed, and a contact hole is selectively formed in the third insulating film 2238.

Next, a third conductive layer 2239 is formed by a photolithography method, a laser direct writing method, an inkjet method, or the like.

Next, a fourth insulating film 2249 is formed, and a contact hole is selectively formed in the fourth insulating film 2249.

Next, a fourth conductive layer 2243 is formed by a photolithography method, a laser direct writing method, an inkjet method, or the like. Here, the fourth conductive layer 2243 has a comb-like shape.

Next, a first alignment film 2240 is formed. Note that after the first alignment film 2240 is formed, rubbing may be performed to control the alignment of liquid crystal molecules.

The first substrate 2231 manufactured as described above, the light shielding film 2244, and the color filter 2245
The spacer 2247 and the second substrate 2246 on which the second alignment film 2242 is manufactured are attached by providing a gap of several micrometers with a sealing material, and a liquid crystal material is injected between the two substrates. A liquid crystal panel can be produced.

Here, materials which can be used for each conductive layer or each insulating film will be described.

The first insulating film 2002 in FIG. 28, the first insulating film 2102 in FIG. 29A, the first insulating film 2132 in FIG. 29B, the first insulating film 2202 in FIG. As the first insulating film 2232 of 30 (B), a silicon oxide film, a silicon nitride film, or a silicon oxynitride film (Si
An insulating film such as OxNy) can be used. Also, these insulating films are silicon oxide films,
An insulating film with a stacked structure in which two or more films of a silicon nitride film, a silicon oxynitride film (SiOxNy), and the like are combined can be used.

The first conductive layer 2003 in FIG. 28, the first conductive layer 2103 in FIG. 29A, the first conductive layer 2133 in FIG. 29B, the first conductive layer 2203 in FIG. As the first conductive layer 2233 of 30 (B), a conductive material such as Mo, Ti, Al, Nd, or Cr can be used. In addition, these conductive layers are made of conductive materials such as Mo, Ti, Al, Nd, and Cr,
A laminated structure in which two or more are combined can also be used.

The second insulating film 2004 in FIG. 28, the second insulating film 2104 in FIG. 29A, the second insulating film 2134 in FIG. 29B, the second insulating film 2204 in FIG. As the second insulating film 2234 of 30 (B), a thermal oxide film, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or the like can be used. Alternatively, a stacked structure in which two or more of a thermal oxide film, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, and the like are combined can be used. Note that in a portion in contact with the semiconductor layer, a silicon oxide film is preferable. By using a silicon oxide film, trap levels at the interface with the semiconductor layer are reduced. Note that, in a portion in contact with Mo, a silicon nitride film is preferable. This is because the silicon nitride film does not oxidize Mo.

The first semiconductor layer 2005 in FIG. 28; the first semiconductor layer 2105 in FIG. 29A;
For the first semiconductor layer 2135 of FIG. 30, the first semiconductor layer 2205 of FIG. 30A, and the first semiconductor layer 2235 of FIG. 30B, silicon or silicon germanium (SiGe) can be used. .

The second semiconductor layer 2006 in FIG. 28; the second semiconductor layer 2106 in FIG. 29A;
As the second semiconductor layer 2136 in FIG. 30A, the second semiconductor layer 2206 in FIG. 30A, and the second semiconductor layer 2236 in FIG. 30B, silicon containing phosphorus or the like can be used.

The second conductive layer 2007 and the third conductive layer 2009 in FIG. 28; the second conductive layer 2107 and the third conductive layer 2109 in FIG. 29A; and the second conductive layer 2137 in FIG. The second conductive layer 2139, the second conductive layer 2207 and the second conductive layer 2209 in FIG. 30A, or the second conductive layer 2237 and the third conductive layer 2239 in FIG. 30B. Conductive layer 224
As a material having transparency of 3, an indium tin oxide (ITO) film in which tin oxide is mixed with indium oxide, an indium tin silicon oxide (ITSO) film in which silicon oxide is mixed with indium tin oxide (ITO), Indium zinc oxide (indium oxide mixed with zinc oxide
An IZO film, a zinc oxide film or a tin oxide film can be used. In addition, IZO is I
It can be formed by sputtering using a target in which 2 to 20 wt% of zinc oxide (ZnO) is mixed with TO.

In addition, the second conductive layer 2007 and the third conductive layer 2009 in FIG. 28, the second conductive layer 2107 and the third conductive layer 2109 in FIG. 29A, and the second conductive layer in FIG. 29B. 2137 and a second conductive layer 2139, a second conductive layer 2207 and a second conductive layer 2209 of FIG.
Alternatively, as a material having reflectivity of the second conductive layer 2237, the second conductive layer 2239, and the fourth conductive layer 2243 in FIG. 30B, Ti, Mo, Ta, Cr, W, Al, or the like is used. be able to. Alternatively, a two-layer structure in which Ti, Mo, Ta, Cr, W and Al are laminated,
A three-layer laminated structure in which Al is sandwiched by metals such as Ti, Mo, Ta, Cr, and W may be used.

The third insulating film 2008 in FIG. 28, the third insulating film 2108 in FIG. 29A, the third insulating film 2138 in FIG. 29B, the third conductive layer 2139 in FIG. As the third insulating film 2208 of 30 (A), and the third insulating film 2238 and the fourth insulating film 2249 of FIG. 30 (B), inorganic materials (silicon oxide, silicon nitride, silicon oxynitride, etc.) or low An organic compound material (photosensitive or non-photosensitive organic resin material) or the like having a dielectric constant can be used. In addition, a material containing siloxane can also be used. In addition, siloxane is silicon (Si)
And oxygen (O) are materials constituting a skeletal structure. As a substituent, an organic group containing at least hydrogen (for example, an alkyl group or an aryl group) is used. Alternatively, a fluoro group may be used as a substituent. Alternatively, as a substituent, an organic group containing at least hydrogen and a fluoro group may be used.

The first alignment film 2010 of FIG. 28, the first alignment film 2110 of FIG. 29A, the first alignment film 2140 of FIG. 29B, the first alignment film 2210 of FIG. As the first alignment film 2240 of 30 (B), a polymer film such as polyimide can be used.

Next, a pixel structure in the case where each liquid crystal mode and a transistor are combined will be described with reference to a top view (layout diagram) of the pixel.

In addition, as a liquid crystal mode, TN (Twisted Nematic) mode, IPS (
In-Plane-Switching mode, FFS (Fringe Field)
Switching mode, MVA (Multi-domain Vertical)
Alignment) mode, PVA (Pattered Vertical Ali)
gnment), ASM (Axially Symmetric aligned mi)
cro-cell mode, OCB (Optical Compensated Birr)
efringence mode, FLC (Ferroelectric Liquid)
Crystal) mode, AFLC (AntiFerroelectric Liqui
d) Crystal or the like can be used.

Note that as the transistor, a thin film transistor (TFT) having a non-single-crystal semiconductor layer typified by amorphous silicon, polycrystalline silicon, microcrystalline (also referred to as microcrystalline or semi-amorphous) silicon, or the like can be used.

Note that a top gate type, a bottom gate type, or the like can be used as a structure of the transistor. As the bottom gate transistor, a channel etch type or a channel protective type can be used.

FIG. 31 shows an example of a top view of a pixel in the case where a TN method and a transistor are combined.

The pixel illustrated in FIG. 31 includes a first transistor 2304, a second transistor 2305, and a third transistor.
Transistor 2306, a first liquid crystal capacitance, a second liquid crystal capacitance, a first holding capacitance, and a second holding capacitance, and are connected to the scanning line 2301, the signal line 2302, and the Cs line 2311. . Note that the equivalent circuit diagram of the pixel configuration shown in FIG. 31 is the same as that of FIG.

In FIG. 31, a pixel electrode constituting a first liquid crystal capacitor corresponds to a pixel electrode 2307, and a pixel electrode constituting a second liquid crystal capacitor corresponds to a pixel electrode 2308. The first storage capacitor is formed of a capacitor line 2312 connected to the Cs line 2311 outside the pixel portion, a semiconductor layer 2309 connected to the pixel electrode 2307, and an insulating film provided therebetween. ing. Similarly to the first storage capacitor, the second storage capacitor is also configured of a capacitor line 2312, a semiconductor layer 2310 connected to the pixel electrode 2308, and an insulating film provided therebetween. Note that the capacitor line 2312 which forms the first storage capacitor and the second storage capacitor is a transistor 2304.
A scanning line 2301 or a Cs line 2301 including a gate electrode constituting the
309 and 2310 are manufactured in the same step as the semiconductor layer including the source region, the drain region, and the channel formation region which form the transistors 2304 to 2306. In addition, the transistors 2304 to 2306 are also included in the insulating film which constitutes the first holding capacitance and the second holding capacitance
A film manufactured in the same step as the gate insulating film that constitutes the above can be used.

As shown in FIG. 31, it is possible to obtain a liquid crystal display device excellent in viewing angle characteristics by utilizing two liquid crystal capacitors having different alignment states. The top view shown in FIG. 31 is an example, and the present invention is not limited to this.

Note that in each of the transistors, the channel width can be increased by providing a structure in which one of the source electrode and the drain electrode surrounds the other electrode. Such a structure is particularly effective when an amorphous semiconductor layer having a mobility lower than that of a crystalline semiconductor layer is used as a semiconductor layer of a transistor included in a pixel.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of the present embodiment can be applied to or combined with the contents (or a part) described in the figures of other embodiments and examples. Or replacement can be freely performed. Furthermore, in the drawings of this embodiment, more drawings can be configured by combining the parts of the other embodiments and the examples with respect to the respective parts.

In this embodiment, the contents (may be a part) described in the other embodiments and examples are as follows:
An example of implementation, an example of slight modification, an example of partial modification, an example of modification, an example of detailed description, an example of application, an example of related parts And so on. Therefore, the contents described in the other embodiments and examples can be freely applied to, combined with, or replaced with this embodiment.

Seventh Embodiment
In this embodiment, various liquid crystal modes will be described using cross-sectional views.

32A and 32B show schematic views of a cross section of the TN mode.

A liquid crystal layer 3300 is sandwiched between a first substrate 3301 and a second substrate 3302 which are disposed to face each other. A first electrode 3305 is formed on the top surface of the first substrate 3301. A second electrode 3306 is formed on the top surface of the second substrate 3302. A first polarizing plate 3303 is disposed on the opposite side of the first substrate 3301 to the liquid crystal layer. Second
A second polarizing plate 3304 is disposed on the opposite side of the liquid crystal layer of the substrate 3302 of FIG. Note that
The first polarizing plate 3303 and the second polarizing plate 3304 are arranged to be in a crossed nicol state.

The first polarizing plate 3303 may be disposed on the top surface of the first substrate 3301. The second polarizing plate 3304 may be disposed on the top surface of the second substrate 3302.

It is sufficient that at least one (or both) of the first electrode 3305 and the second electrode 3306 have translucency (transmissive or reflective). Alternatively, both electrodes may be translucent, and part of one of the electrodes may be reflective (semi-transmissive).

FIG. 32A is a schematic view of a cross section in the case where a voltage is applied to the first electrode 3305 and the second electrode 3306 (referred to as a vertical electric field mode). Since liquid crystal molecules are aligned vertically, light from the backlight is not affected by birefringence of the liquid crystal molecules. And the first polarizing plate 3303
And the second polarizing plate 3304 are arranged so as to be in a cross nicol state, light from the backlight can not pass through the substrate. Therefore, black display is performed.

FIG. 32B is a schematic view of a cross section when voltage is not applied to the first electrode 3305 and the second electrode 3306. Liquid crystal molecules are arranged side by side, and the first electrode 3305 to the second electrode 3
The light from the backlight is affected by the birefringence of the liquid crystal molecules since the light is rotated through 306. Then, since the first polarizing plate 3303 and the second polarizing plate 3304 are arranged in cross nicol, light from the backlight passes through the substrate. Therefore, white display is performed. It is a so-called normally white mode.

By controlling the voltage applied to the first electrode 3305 and the second electrode 3306, it is possible to control the state of liquid crystal molecules, that is, the alignment. Therefore, since light from the backlight can be controlled by the liquid crystal molecules, predetermined image display can be performed.

The liquid crystal display device having the structure shown in FIGS. 32A and 32B can perform full color display by providing a color filter. The color filter can be provided on the first substrate 3301 side or the second substrate 3302 side.

The liquid crystal material used in the TN mode may be a known one.

FIGS. 33A and 33B are schematic views of a cross section of the VA mode. The VA mode is a mode in which liquid crystal molecules are oriented perpendicular to the substrate when no electric field is applied.

A liquid crystal layer 3400 is sandwiched between a first substrate 3401 and a second substrate 3402 which are disposed to face each other. A first electrode 3405 is formed on the top surface of the first substrate 3401. A second electrode 3406 is formed on the top surface of the second substrate 3402. A first polarizing plate 3403 is disposed on the opposite side of the first substrate 3401 to the liquid crystal layer. Second
A second polarizing plate 3404 is disposed on the opposite side of the substrate 3402 to the liquid crystal layer. Note that
The first polarizing plate 3403 and the second polarizing plate 3404 are arranged to be in a crossed nicol state.

The first polarizing plate 3403 may be disposed on the top surface of the first substrate 3401. The second polarizing plate 3404 may be disposed on the top surface of the second substrate 3402.

At least one (or both) of the first electrode 3405 and the second electrode 3406 may have a light-transmitting property (transmissive or reflective). Alternatively, both electrodes may be translucent, and part of one of the electrodes may be reflective (semi-transmissive).

FIG. 33A is a schematic view of a cross section in the case where a voltage is applied to the first electrode 3405 and the second electrode 3406 (referred to as a vertical electric field mode). Since liquid crystal molecules are aligned horizontally, light from the backlight is affected by birefringence of the liquid crystal molecules. Then, since the first polarizing plate 3403 and the second polarizing plate 3404 are arranged to be in a crossed nicol state, light from the backlight passes through the substrate. Therefore, white display is performed.

FIG. 33B is a schematic view of a cross section when voltage is not applied to the first electrode 3405 and the second electrode 3406. Since liquid crystal molecules are aligned vertically, light from the backlight is not affected by birefringence of the liquid crystal molecules. Then, since the first polarizing plate 3403 and the second polarizing plate 3404 are arranged to be in a crossed nicol state, light from the backlight does not pass through the substrate. Therefore, black display is performed. It is a so-called normally black mode.

By controlling the voltage applied to the first electrode 3405 and the second electrode 3406, the state of liquid crystal molecules, that is, the alignment can be controlled. Therefore, since light from the backlight can be controlled by the liquid crystal molecules, predetermined image display can be performed.

The liquid crystal display device having the structure shown in FIGS. 34A and 34B can perform full color display by providing a color filter. The color filter can be provided on the first substrate 3401 side or the second substrate 3402 side.

The liquid crystal material used for the VA mode may be a known one.

33C and 33D show schematic views of a cross section of the MVA mode. The MVA mode is a method of compensating each other for the viewing angle dependency of each part.

A liquid crystal layer 3410 is sandwiched between a first substrate 3411 and a second substrate 3412 which are disposed to face each other. A first electrode 3415 is formed on the top surface of the first substrate 3411. A second electrode 3416 is formed on the top surface of the second substrate 3412. On the first electrode 3415, a first protrusion 3417 is formed for orientation control. On the second electrode 3416, a second protrusion 3418 is formed for orientation control. A first polarizing plate 3413 is disposed on the opposite side of the first substrate 3411 to the liquid crystal layer. Second substrate 3
A second polarizing plate 3414 is disposed on the opposite side of the liquid crystal layer 412. Note that the first polarizing plate 3413 and the second polarizing plate 3414 are arranged to be in a cross nicol state.

The first polarizing plate 3413 may be disposed on the top surface of the first substrate 3411. The second polarizing plate 3414 may be disposed on the top surface of the second substrate 3412.

At least one (or both) of the first electrode 3415 and the second electrode 3416 may have a light-transmitting property (transmissive or reflective). Alternatively, both electrodes may be translucent, and part of one of the electrodes may be reflective (semi-transmissive).

FIG. 33C is a schematic view of a cross section in the case where a voltage is applied to the first electrode 3415 and the second electrode 3416 (referred to as a vertical electric field mode). The light from the backlight is affected by the birefringence of liquid crystal molecules. Then, since the first polarizing plate 3413 and the second polarizing plate 3414 are arranged to be in a crossed nicol state, light from the backlight passes through the substrate. Therefore, white display is performed. In addition, the liquid crystal molecules have the first protrusion 3417 and the second protrusion 341.
Under the influence of 8, the first protrusion 3417 and the second protrusion 3418 are in a state of falling and aligned. Therefore, it is possible to further improve the viewing angle.

FIG. 33D is a schematic view of a cross section when voltage is not applied to the first electrode 3415 and the second electrode 3416. Since liquid crystal molecules are aligned vertically, light from the backlight is not affected by birefringence of the liquid crystal molecules. Then, since the first polarizing plate 3413 and the second polarizing plate 3414 are arranged to be in a cross nicol state, light from the backlight does not pass through the substrate. Therefore, black display is performed. It is a so-called normally black mode.

Note that by controlling the voltage applied to the first electrode 3415 and the second electrode 3416, the state of the liquid crystal molecules, that is, the alignment can be controlled. Therefore, since light from the backlight can be controlled by the liquid crystal molecules, predetermined image display can be performed.

The liquid crystal display device having the structure shown in FIGS. 36C and 36D can perform full color display by providing a color filter. The color filter can be provided on the first substrate 3411 side or the second substrate 3412 side.

The liquid crystal material used in the MVA mode may be a known one.

34A and 34B show schematic views of a cross section of the OCB mode. In the OCB mode, the alignment of the liquid crystal molecules in the liquid crystal layer optically forms a compensation state, and thus the viewing angle dependency is small. The state of this liquid crystal molecule is called bend alignment.

A liquid crystal layer 3500 is sandwiched between a first substrate 3501 and a second substrate 3502 which are disposed to face each other. A first electrode 3505 is formed on the top surface of the first substrate 3501. A second electrode 3506 is formed on the top surface of the second substrate 3502. A first polarizing plate 3503 is disposed on the opposite side of the first substrate 3501 to the liquid crystal layer. Second
A second polarizing plate 336 is disposed on the opposite side of the substrate 3502 to the liquid crystal layer. Note that the first polarizing plate 3503 and the second polarizing plate 336 are arranged to be in a cross nicol state.

The first polarizing plate 3503 may be disposed on the top surface of the first substrate 3501. The second polarizing plate 336 may be disposed on the top surface of the second substrate 3502.

It is sufficient that at least one (or both) of the first electrode 3505 and the second electrode 3506 have translucency (transmissive or reflective). Alternatively, both electrodes may be translucent, and part of one of the electrodes may be reflective (semi-transmissive).

FIG. 34A is a schematic view of a cross section in the case where a voltage is applied to the first electrode 3505 and the second electrode 3506 (referred to as a vertical electric field mode). Since liquid crystal molecules are aligned vertically, light from the backlight is not affected by birefringence of the liquid crystal molecules. And, the first polarizing plate 3503
The light from the backlight does not pass through the substrate because the second polarizing plate 336 is disposed so as to be in a cross nicol state. Therefore, black display is performed.

FIG. 34B is a schematic view of a cross section when voltage is not applied to the first electrode 3505 and the second electrode 3506. Since liquid crystal molecules are in a bend alignment state, light from the backlight is affected by birefringence of the liquid crystal molecules. Then, since the first polarizing plate 3503 and the second polarizing plate 336 are arranged in cross nicol, light from the backlight passes through the substrate. Therefore, white display is performed. It is a so-called normally white mode.

Note that by controlling the voltage applied to the first electrode 3505 and the second electrode 3506, the state of liquid crystal molecules, that is, the alignment can be controlled. Therefore, since light from the backlight can be controlled by the liquid crystal molecules, predetermined image display can be performed.

The liquid crystal display device having the structure shown in FIGS. 34A and 34B can perform full color display by providing a color filter. The color filter can be provided on the first substrate 3501 side or the second substrate 3502 side.

The liquid crystal material used in the OCB mode may be a known one.

34C and 34D show schematic views of a cross section in the FLC mode or the AFLC mode.

A liquid crystal layer 3510 is sandwiched between a first substrate 3511 and a second substrate 3512 which are disposed to face each other. A first electrode 3515 is formed on the top surface of the first substrate 3511. A second electrode 3516 is formed on the top surface of the second substrate 3512. A first polarizing plate 3513 is disposed on the opposite side of the first substrate 3511 to the liquid crystal layer. Second
A second polarizing plate 3514 is disposed on the opposite side of the substrate 3512 to the liquid crystal layer. Note that
The first polarizing plate 3513 and the second polarizing plate 3514 are arranged to be in a crossed nicol state.

The first polarizing plate 3513 may be disposed on the top surface of the first substrate 3511. The second polarizing plate 3514 may be disposed on the top surface of the second substrate 3512.

At least one (or both) of the first electrode 3515 and the second electrode 3516 may have a light-transmitting property (transmission type or reflection type). Alternatively, both electrodes may be translucent, and part of one of the electrodes may be reflective (semi-transmissive).

FIG. 34C is a schematic view of a cross section in the case where a voltage is applied to the first electrode 3515 and the second electrode 3516 (referred to as a vertical electric field mode). Since liquid crystal molecules are aligned horizontally in a direction shifted from the rubbing direction, light from the backlight is affected by birefringence of the liquid crystal molecules. Then, since the first polarizing plate 3513 and the second polarizing plate 3514 are arranged to be in a crossed nicol state, light from the backlight passes through the substrate. Therefore, white display is performed.

FIG. 34D is a schematic view of a cross section when voltage is not applied to the first electrode 3515 and the second electrode 3516. Since liquid crystal molecules are aligned horizontally along the rubbing direction, light from the backlight is not affected by birefringence of the liquid crystal molecules. And, the first polarizing plate 3
The light from the backlight does not pass through the substrate because the second polarizing plate 3514 and the second polarizing plate 3514 are disposed to be in a crossed nicol state. Therefore, black display is performed. It is a so-called normally black mode.

Note that by controlling the voltage applied to the first electrode 3515 and the second electrode 3516, the state of liquid crystal molecules, that is, the alignment can be controlled. Therefore, since light from the backlight can be controlled by the liquid crystal molecules, predetermined image display can be performed.

A liquid crystal display device having a structure shown in FIGS. 34C and 34D can perform full color display by providing a color filter. The color filter can be provided on the first substrate 3511 side or the second substrate 3512 side.

Known liquid crystal materials may be used for the FLC mode or the AFLC mode.

FIGS. 35A and 35B show schematic views of a cross section of the IPS mode. The IPS mode is a mode in which liquid crystal molecules are always rotated in a plane with respect to a substrate, and electrodes have a transverse electric field method provided on only one substrate side.

A liquid crystal layer 3600 is sandwiched between a first substrate 3601 and a second substrate 3602 which are disposed to face each other. A first electrode 3605 and a second electrode 3606 are formed on the top surface of the first substrate 3601. A first polarizing plate 3603 is disposed on the opposite side of the first substrate 3601 to the liquid crystal layer. A second polarizing plate 3604 is disposed on the opposite side of the second substrate 3602 to the liquid crystal layer. Note that the first polarizing plate 3603 and the second polarizing plate 3604 are arranged to be in a cross nicol state.

The first polarizing plate 3603 may be disposed on the top surface of the first substrate 3601. The second polarizing plate 3604 may be disposed on the top surface of the second substrate 3602.

At least one (or both) of the first electrode 3605 and the second electrode 3606 may have a light-transmitting property (a transmissive type or a reflective type). Alternatively, both electrodes may be translucent, and part of one of the electrodes may be reflective (semi-transmissive).

FIG. 35A is a schematic view of a cross section in the case where voltage is applied to the first electrode 3605 and the second electrode 3606. Since liquid crystal molecules are aligned along electric lines of force that deviate from the rubbing direction, light from the backlight is affected by birefringence of the liquid crystal molecules. Then, since the first polarizing plate 3603 and the second polarizing plate 3604 are disposed to be in a crossed nicol state, light from the backlight passes through the substrate. Therefore, white display is performed.

FIG. 35B is a schematic view of a cross section when voltage is not applied to the first electrode 3605 and the second electrode 3606. Since liquid crystal molecules are aligned horizontally along the rubbing direction, light from the backlight is not affected by birefringence of the liquid crystal molecules. And, the first polarizing plate 3
Light from the backlight does not pass through the substrate because the second polarizing plate 3604 and the second polarizing plate 3604 are arranged to be in a crossed nicol state. Therefore, black display is performed. It is a so-called normally black mode.

By controlling the voltage applied to the first electrode 3605 and the second electrode 3606, the state of liquid crystal molecules, that is, the alignment can be controlled. Therefore, since light from the backlight can be controlled by the liquid crystal molecules, predetermined image display can be performed.

The liquid crystal display device having the structure shown in FIGS. 35A and 35B can perform full color display by providing a color filter. The color filter can be provided on the first substrate 3601 side or the second substrate 3602 side.

The liquid crystal material used in the IPS mode may be a known one.

FIGS. 35C and 35D are schematic views of a cross section of the FFS mode. Also in the FFS mode, the liquid crystal molecules are always rotated in a plane with respect to the substrate, and the electrodes are in the lateral electric field mode provided only on one substrate side.

A liquid crystal layer 3610 is sandwiched between a first substrate 3611 and a second substrate 3612 which are disposed to face each other. A second electrode 3616 is formed on the top surface of the first substrate 3611. An insulating film 3617 is formed on the top surface of the second electrode 3616. A second electrode 3616 is formed over the insulating film 3617. A first polarizing plate 3613 is disposed on the opposite side of the first substrate 3611 to the liquid crystal layer. A second polarizing plate 3614 is disposed on the opposite side of the second substrate 3612 to the liquid crystal layer. The first polarizing plate 3613 and the second polarizing plate
The polarizing plate 3614 is disposed so as to be in a cross nicol state.

The first polarizing plate 3613 may be disposed on the top surface of the first substrate 3611. The second polarizer 3614 may be disposed on the top surface of the second substrate 3612.

At least one (or both) of the first electrode 3615 and the second electrode 3616 may have a light-transmitting property (transmissive or reflective). Alternatively, both electrodes may be translucent, and part of one of the electrodes may be reflective (semi-transmissive).

FIG. 35C is a schematic view of a cross section when voltage is applied to the first electrode 3615 and the second electrode 3616. Since liquid crystal molecules are aligned along electric lines of force that deviate from the rubbing direction, light from the backlight is affected by birefringence of the liquid crystal molecules. Then, since the first polarizing plate 3613 and the second polarizing plate 3614 are arranged in cross nicol, light from the backlight passes through the substrate. Therefore, white display is performed.

FIG. 35D is a schematic view of a cross section when voltage is not applied to the first electrode 3615 and the second electrode 3616. Since liquid crystal molecules are aligned horizontally along the rubbing direction, light from the backlight is not affected by birefringence of the liquid crystal molecules. And, the first polarizing plate 3
The light from the backlight does not pass through the substrate because the second polarizing plate 3614 and the second polarizing plate 3614 are arranged to be in a crossed nicol state. Therefore, black display is performed. It is a so-called normally black mode.

Note that by controlling the voltage applied to the first electrode 3615 and the second electrode 3616, the state of liquid crystal molecules, that is, the alignment can be controlled. Therefore, since light from the backlight can be controlled by the liquid crystal molecules, predetermined image display can be performed.

The liquid crystal display device having the structure shown in FIGS. 35C and 35D can perform full color display by providing a color filter. The color filter can be provided on the first substrate 3611 side or the second substrate 3612 side.

The liquid crystal material used in the FFS mode may be a known one.

Next, various liquid crystal modes will be described using a top view.

FIG. 36 shows a top view of one of the plurality of liquid crystal capacitors included in the pixel to which the MVA mode is applied.

FIG. 36 shows the first electrode 3701, the second electrode (3702a, 3702b, 3702c),
And projections 3703 are shown. The first electrode 3701 is formed on the entire surface of the counter substrate. The second electrodes (3702a, 3702b, 3702c) so that the shape becomes a V shape
) Is formed. Second electrodes (3702a, 3702b, 3702c) on the first electrode 3701 so that the shape corresponds to the second electrodes (3702a, 3702b, 3702c)
) Is formed.

The openings of the second electrodes (3702a, 3702b, 3702c) function like projections.

In the case where voltage is applied to the first electrode 3701 and the second electrodes (3702a, 3702b, 3702c) (referred to as a vertical electric field mode), liquid crystal molecules are generated in the second electrodes (3702a, 3702b,
With respect to the opening 3702 c) and the protrusion 3703, it falls down and is aligned. Therefore, it is possible to improve the viewing angle. Note that when the pair of polarizing plates is arranged to be in a crossed nicol, light from the backlight passes through the substrate, so white display is performed.

In the case where voltage is not applied to the first electrode 3701 and the second electrode (3702a, 3702b, 3702c), liquid crystal molecules are aligned vertically. When the pair of polarizing plates are arranged to be crossed nicols, light from the backlight does not pass through the panel,
Black display is performed. It is a so-called, normally black mode.

Note that by controlling voltages applied to the first electrode 3701 and the second electrodes (3702a, 3702b, and 3702c), the state of liquid crystal molecules, that is, the alignment can be controlled.
Therefore, since light from the backlight can be controlled by the liquid crystal molecules, predetermined image display can be performed.

The liquid crystal material used in the MVA mode may be a known one.

37 (A), (B), (C) and (D) show top views of one liquid crystal capacitor to which the IPS mode is applied. The IPS mode is a mode in which liquid crystal molecules are always rotated in a plane with respect to a substrate, and electrodes have a transverse electric field method provided on only one substrate side.

In the IPS mode, the pair of electrodes are formed to have different shapes.

FIG. 37A shows a first electrode 3801 and a second electrode 3802. The first electrode 3801 and the second electrode 3802 have a corrugated shape.

FIG. 37B illustrates the first electrode 3811 and the second electrode 3812. The first electrode 3811 and the second electrode 3812 are shaped to have concentric openings.

FIG. 37C illustrates a first electrode 3832 and a second electrode 3832. The first electrode 3831 and the second electrode 3832 have a comb-like shape and a partially overlapping shape.

FIG. 37D illustrates a first electrode 3841 and a second electrode 3842. The first electrode 3841 and the second electrode 3842 have a comb-like shape and have a shape in which the electrodes are engaged with each other.

The first electrode (3801, 3811, 3821, 3831) and the second electrode (3802, 3
In the case where a voltage is applied to 812, 3822, 3832), the liquid crystal molecules are aligned along electric lines of force that deviate from the rubbing direction. When the pair of polarizing plates is arranged to be in a crossed nicol, light from the backlight passes through the substrate, so white display is performed.

The first electrode (3801, 3811, 3821, 3831) and the second electrode (3802, 3
In the case where no voltage is applied to 812, 3822, 3832), the liquid crystal molecules are aligned horizontally along the rubbing direction. When the pair of polarizing plates is arranged to be in a crossed nicol, light from the backlight does not pass through the substrate, so black display is performed. It is a normally black mode to say.

Note that by controlling the voltage applied to the first electrode and the second electrode, it is possible to control the state of liquid crystal molecules, that is, the alignment. Therefore, since light from the backlight can be controlled by the liquid crystal molecules, predetermined image display can be performed.

The liquid crystal material used in the IPS mode may be a known one.

38 (A), (B), (C) and (D) show top views of one liquid crystal capacitor to which the FFS mode is applied. The FFS mode is a mode in which liquid crystal molecules are always rotated in a plane with respect to a substrate, and the electrodes adopt a transverse electric field method provided on only one substrate side.

In the FFS mode, the first electrode is formed in various shapes on the top surface of the second electrode.

FIG. 38A illustrates a first electrode 3901 and a second electrode 3902. The first electrode 3901 is in the shape of a crook. The second electrode 3902 may not be patterned.

FIG. 38B illustrates a first electrode 3911 and a second electrode 3912. The first electrode 3911 has a concentric shape. The second electrode 3912 may not be patterned.

FIG. 38C illustrates a first electrode 3931 and a second electrode 3932. The first electrode 3931 has a comb shape and has a shape in which the electrodes are engaged with each other. The second electrode 3932 may not be patterned.

FIG. 38D illustrates a first electrode 3941 and a second electrode 3942. The first electrode 3941 has a comb-like shape. The second electrode 3942 may not be patterned.

The first electrode (3901, 3911, 3921, 3931) and the second electrode (3902, 392)
When a voltage is applied to (912, 3922, 3932), the liquid crystal molecules are aligned along the lines of electric force shifted from the rubbing direction. When the pair of polarizing plates is arranged to be in a crossed nicol, light from the backlight passes through the substrate, so white display is performed.

The first electrode (3901, 3911, 3921, 3931) and the second electrode (3902, 392)
When no voltage is applied to 912, 3922 and 3932), liquid crystal molecules are aligned horizontally along the rubbing direction. When the pair of polarizing plates is arranged to be in a crossed nicol, light from the backlight does not pass through the substrate, so black display is performed. It is a normally black mode to say.

Note that by controlling the voltage applied to the first electrode and the second electrode, it is possible to control the state of liquid crystal molecules, that is, the alignment. Therefore, since light from the backlight can be controlled by the liquid crystal molecules, predetermined image display can be performed.

The liquid crystal material used in the IPS mode may be a known one.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of the present embodiment can be applied to or combined with the contents (or a part) described in the figures of other embodiments and examples. Or replacement can be freely performed. Furthermore, in the drawings of this embodiment, more drawings can be configured by combining the parts of the other embodiments and the examples with respect to the respective parts.

In this embodiment, the contents (may be a part) described in the other embodiments and examples are as follows:
An example of implementation, an example of slight modification, an example of partial modification, an example of modification, an example of detailed description, an example of application, an example of related parts And so on. Therefore, the contents described in the other embodiments and examples can be freely applied to, combined with, or replaced with this embodiment.

Eighth Embodiment
In the present embodiment, the peripheral portion of the liquid crystal panel will be described.

FIG. 39 shows a backlight unit 2601 called an edge light type, and a liquid crystal panel 26.
17 shows an example of a liquid crystal display device having a voltage 07. The edge light type is a type in which a light source is disposed at an end portion of the backlight unit and light emission of the light source is emitted from the entire light emitting surface. The edge light type backlight unit is thin and power saving can be achieved.

The backlight unit 2601 includes a diffusion plate 2602, a light guide plate 2603, a reflection plate 2604,
A lamp reflector 2605 and a light source 2606 are provided.

The light source 2606 has a function of emitting light as needed. For example, as the light source 2606, 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 2605 has a function of efficiently guiding the light emitted from the light source 2606 to the light guide plate 2603. The light guide plate 2603 has a function of totally reflecting the light from the light source 2603 and guiding the light to the entire surface. The diffusion plate 2602 has a function of reducing unevenness in brightness. The reflector 2604 is
It has a function of reflecting light recycled from the light guide plate 2603 in the opposite direction from the liquid crystal panel 2603 for reuse.

A control circuit for adjusting the luminance of the light source 2606 is connected to the backlight unit 2601. The control circuit can adjust the luminance of the light source 2606.

40 (A), (B), (C) and (D) are diagrams showing the detailed configuration of the edge light type backlight unit. The description of the diffusion plate, the light guide plate, the reflection plate and the like will be omitted.

A backlight unit 2701 shown in FIG. 40A has a configuration using a cold cathode tube 2703 as a light source. And, in order to reflect the light from the cold cathode tube 2703 efficiently, a lamp reflector 2702 is provided. Such a configuration is often used for large display devices.

The backlight unit 2711 shown in FIG. 40B includes a light emitting diode (LE) as a light source.
D) A configuration using 2713. For example, a light emitting diode (W) 2713 that emits white light
Are arranged at predetermined intervals. A lamp reflector 2712 is provided to efficiently reflect the light from the light emitting diode 2713.

Since the light emission intensity of the light emitting diode is strong, the configuration using the light emitting diode is suitable for a large display device. Further, since the light emitting diode is excellent in color reproducibility, an image faithful to the input image information can be displayed. In addition, since the light emitting diode is small, the arrangement area can be reduced. Therefore, the frame of the display device can be narrowed.

When the light emitting diode is mounted on a large display device, the light emitting diode can be disposed on the back of the substrate. The light emitting diodes maintain a predetermined distance, and light emitting diodes of respective colors are sequentially disposed.

The backlight unit 2721 shown in FIG. 40C includes a light emitting diode (LED) 2723 for each color of RGB, a light emitting diode (LED) 2724, and a light emitting diode (LE) as light sources.
D) A configuration using 2725. The light emitting diodes 2723 (LEDs), the light emitting diodes (LEDs) 2724, and the light emitting diodes (LEDs) 2725 of each color of RGB are arranged at predetermined intervals, respectively. The color reproducibility can be improved by using a light emitting diode (LED) 2723, a light emitting diode (LED) 2724, and a light emitting diode (LED) 2725 of each color of RGB. In addition, a lamp reflector 2722 is provided to efficiently reflect the light from the light emitting diode.

Since the brightness of the light emitting diode is high, a configuration using light emitting diodes of respective colors of RGB as light sources is suitable for a large display device. Further, since the light emitting diode is excellent in color reproducibility, an image faithful to the input image information can be displayed. In addition, since the light emitting diode is small, the arrangement area can be reduced. Therefore, the frame of the display device can be narrowed.

Note that color display can be performed by sequentially turning on the RGB light emitting diodes according to time. It can be displayed in the so-called field sequential mode.

Note that a light emitting diode that emits white light and a light emitting diode (LED) 2723 of each color of RGB
, A light emitting diode (LED) 2724, and a light emitting diode (LED) 2725 can be combined.

When the light emitting diode is mounted on a large display device, the light emitting diode can be disposed on the back of the substrate. Also, each of the light emitting diodes maintains a predetermined distance, and the light emitting diodes of each color are arranged in order. Such arrangement can enhance color reproducibility.

The backlight unit 2731 shown in FIG. 40D includes a light emitting diode (LED) 2733 for each color of RGB, a light emitting diode (LED) 2734, and a light emitting diode (LE) as light sources.
D) A configuration using 2735. For example, light emitting diodes (LEDs) 27 for each color of RGB
Among light emitting diodes (LEDs) 2734 and light emitting diodes (LEDs) 2735, light emitting diodes having a low light emission intensity (for example, green) are arranged, and in FIG. With such a configuration, color reproducibility can be further enhanced. In addition, a lamp reflector 2732 is provided to efficiently reflect the light from the light emitting diode.

Since the light emission intensity of the light emitting diode is high, a configuration using light emitting diodes of respective colors of RGB as light sources is suitable for a large display device. Further, since the light emitting diode is excellent in color reproducibility, an image faithful to the input image information can be displayed. In addition, since the light emitting diode is small, the arrangement area can be reduced. Therefore, the frame of the display device can be narrowed.

Note that color display can be performed by sequentially turning on the RGB light emitting diodes according to time.

In addition, a light emitting diode that emits white light and a light emitting diode (LED) 2733 of each color of RGB
, A light emitting diode (LED) 2734, and a light emitting diode (LED) 2735 can be combined.

When the light emitting diode is mounted on a large display device, the light emitting diode can be disposed on the back of the substrate. Each of the light emitting diodes maintains a predetermined distance, and light emitting diodes of each color are arranged in order. Such arrangement can enhance color reproducibility.

In FIG. 41A, a backlight unit 2800 called direct type and a liquid crystal panel 280 are used.
7 shows an example of a liquid crystal display device having the fifth embodiment. The direct type is a method in which the light emission of the light source is emitted from the entire light emitting surface by arranging the light source directly under the light emitting surface. The direct type backlight unit can efficiently use the amount of light emitted.

The backlight unit 2800 includes a diffusion plate 2801, a light shielding plate 2802, a lamp reflector 2803 and a light source 2804.

The light source 2804 has a function of emitting light as needed. For example, as the light source 2805, 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 2803 efficiently emits light from the light source 2804 as the diffusion plate 2801 and the light shielding plate 2.
It has a function leading to 802. The light shielding plate 2802 has a function of reducing unevenness in lightness by increasing the light shielding as the light intensity increases in accordance with the arrangement of the light sources 2804. Diffusion plate 2801
Has a function of further reducing unevenness in lightness.

A control circuit for adjusting the luminance of the light source 2804 is connected to the backlight unit 2800. The control circuit can adjust the luminance of the light source 2804.

FIG. 41B shows a backlight unit 3015 called direct type, and a liquid crystal panel 301.
7 illustrates an example of a liquid crystal display device having 0.

The backlight unit 2810 includes a diffusion plate 2811, a light shielding plate 2812, a lamp reflector 2813, light sources (R) 2814a of respective colors of RGB, a light source (G) 2814b, and a light source (B) 2
It is comprised by 814c.

The light sources 2814 a (R), light sources 2814 b (G), and light sources 2814 c (B) of each color of RGB have a function of emitting light as needed. For example, light source 2814 a (R), light source 2814 b
As the (G) and the light source 2814c (B), 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 2813 has a function of efficiently guiding the light emission of the light source 2814 to the diffusion plate 2811 and the light shielding plate 2812. The light shielding plate 2812 is
There is a function of reducing unevenness in lightness by increasing the light shielding as the light intensity increases in accordance with the arrangement of the light source 2814. The diffusion plate 2811 further has a function of reducing unevenness in brightness.

Note that the backlight unit 2810 includes a light source 2814 a (R) of each color of RGB, a light source 2
A control circuit for adjusting the luminance of the light source 814 b (G) and the light source 2814 c (B) is connected. By this control circuit, the light sources 2814 a (R) of each color of RGB, the light sources 2814 b (G
And the light source 2814 c (B) can be adjusted.

FIG. 42 is a view showing an example of the configuration of a polarizing plate (also referred to as a polarizing film).

The polarizing film 2900 includes a protective film 2901, a substrate film 2902, a PVA polarizing film 2903, a substrate film 2904, an adhesive layer 2905, and a release film 2906.

The PVA polarizing film 2903 has a function of converting light into light in a certain vibration direction (linearly polarized light). Specifically, the PVA polarizing film 2903 contains molecules (polarizers) in which the density of electrons differs greatly in the longitudinal and lateral directions. It is possible to make it linearly polarized light by the PVA polarizing film 2903 in which the directions of the molecules whose density of electrons greatly differs in the longitudinal and transverse directions are aligned.

As an example, the PVA polarizing film 2903 is made of polyvinyl alcohol (Poly Vin)
It is possible to obtain a film in which iodine molecules are aligned in a certain direction by doping the polymer film of yl Alcohol with iodine compound and pulling the PVA film in a certain direction. The light parallel to the long axis of the iodine molecule is absorbed by the iodine molecule. In addition, you may use a dichroic dye instead of iodine as a highly durable use and high heat resistant use. The dye is
The liquid crystal display device is required to have durability and heat resistance such as an on-vehicle LCD or a projector LCD.

In addition, the PVA polarizing film 2903 is a film (substrate film
The reliability can be increased by sandwiching the two with the substrate film 2904). Also, PVA
The polarizing film 2903 may be sandwiched by a triacetyl cellulose (TAC) film having high transparency and high durability. Such substrate films and TAC films are P
It functions as a protective layer of a polarizer that the VA polarizing film 2903 has.

On the substrate film (substrate film 2904), a pressure-sensitive adhesive layer 2905 to be attached to the glass substrate of the liquid crystal panel is attached. In addition, the adhesive layer 2905 is formed by apply | coating an adhesive to the substrate film (substrate film 2904) of one side. The pressure-sensitive adhesive layer 2905 is provided with a release film 2906 (separate film).

The other substrate film (substrate film 2902) is provided with a protective film 2901.

A hard coat scattering layer (anti-glare layer) may be provided on the surface of the polarizing film 2900. The hard coat scattering layer has fine asperities formed on its surface by AG treatment, and has an antiglare function to scatter external light, so that it is possible to prevent external light from being reflected on the liquid crystal panel. Thus, surface reflection can be prevented.

In addition, a plurality of optical thin film layers with different refractive indexes may be provided on the surface of the polarizing film 2900 (also referred to as anti-reflection processing or AR processing). The multi-layered optical thin film layers having different refractive indices can reduce the surface reflectance by the interference effect of light.

FIG. 43 is a diagram showing an example of a system block of a liquid crystal display device.

As shown in FIG. 43A, in the pixel portion 3005, the signal line 3012 is a signal line driver circuit 300.
It is arranged extending from 3. In addition, a scan line 3010 extends from the scan line driver circuit 3004. Then, a plurality of pixels are arranged in a matrix in the intersection region of the signal line 3012 and the scan line 3010. Note that each of the plurality of pixels has a switching element, and the details of the pixel portion 3005 have been described in the above embodiment and thus are omitted here.

In FIG. 43A, the driver circuit portion 3008 includes a control circuit 3002 and a signal line driver circuit 30.
And the scanning line driving circuit 3004. The video signal 3001 is input to the control circuit 3002. Control circuit 3002 responds to control signal 3001 to drive signal line drive circuit 30.
And control the scanning line driving circuit 3004. Therefore, the control circuit 3002 inputs control signals to the signal line driver circuit 3003 and the scan line driver circuit 3004. Then, in response to the control signal, the signal line drive circuit 3003 inputs a video signal to the signal line 3012,
The scan line driver circuit 3004 inputs a scan signal to the scan line 3010. Then, the switching element of the pixel is selected according to the scanning signal, and the video signal is input to the pixel electrode of the pixel.

The control circuit 3002 also controls the power supply 3007 according to the control signal 3001. Note that the power supply 3007 has means for supplying power to the lighting means 3006. Lighting means 30
As 06, an edge light type backlight unit or a direct type backlight unit can be used. In addition, a front light may be used as the lighting unit 3006. The front light is a plate-like light unit including a light emitter and a light guide mounted on the front side of the pixel portion to illuminate the whole. With such an illumination means, the pixel portion can be illuminated uniformly with low power consumption.

For example, as shown in FIG. 43 (B), the scanning line driving circuit 3004 includes a shift register 3041,
A circuit functioning as the level shifter 3042 and the buffer 3043 is included. A signal such as a gate start pulse (GSP) and a gate clock signal (GCK) is input to the shift register 3041 from the control circuit 2902.

As shown in FIG. 43C, the signal line driver circuit 3003 includes circuits functioning as a shift register 3031, a first latch 3032, a second latch 3033, a level shifter 3034, and a buffer 3035. The circuit functioning as the buffer 3035 is a circuit having a function of amplifying a weak signal and includes an operational amplifier and the like. A signal such as a start pulse (SSP), a source clock signal (SCK), etc.
Data (DATA) such as a video signal is input to 2. The second latch 3033 can temporarily hold a latch (LAT) signal, and inputs the signal to the pixel portion 3005 all at once. This is called line sequential drive. Therefore, in the case of pixels that perform point-sequential drive instead of line-sequential drive,
The second latch may be unnecessary.

In the present embodiment, a known liquid crystal panel can be used. For example, as a liquid crystal panel, a structure in which a liquid crystal layer is sealed between two substrates can be used.
A transistor, a capacitor, a pixel electrode, an alignment film, and the like are formed over one of the substrates. A polarizing plate, a retardation plate or a prism sheet may be disposed on the side opposite to the upper surface of the substrate. On the other substrate, a color filter, a black matrix, a counter electrode, an alignment film, and the like are formed. A polarizing plate or a retardation plate may be disposed 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. Note that three-dimensional display can be performed by arranging a slit (grating) on the upper surface side of one of the substrates or the opposite side thereof.

In addition, it is possible to arrange a polarizing plate, a retardation plate and a prism sheet between two substrates respectively. Alternatively, it can be integral with any of the two substrates.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of the present embodiment can be applied to or combined with the contents (or a part) described in the figures of other embodiments and examples. Or replacement can be freely performed. Furthermore, in the drawings of this embodiment, more drawings can be configured by combining the parts of the other embodiments and the examples with respect to the respective parts.

In this embodiment, the contents (may be a part) described in the other embodiments and examples are as follows:
An example of implementation, an example of slight modification, an example of partial modification, an example of modification, an example of detailed description, an example of application, an example of related parts And so on. Therefore, the contents described in the other embodiments and examples can be freely applied to, combined with, or replaced with this embodiment.

(Embodiment 9)
In the present embodiment, a method of driving a display device will be described. In particular, a method of driving a liquid crystal display device is described.

The liquid crystal panel that can be used for the liquid crystal display device described in this embodiment has a structure in which a liquid crystal material is sandwiched between two substrates. The two substrates each include an electrode for controlling an electric field applied to the liquid crystal material. A liquid crystal material is a material whose optical and electrical properties are changed by an externally applied electric field. Therefore, the liquid crystal panel
It is a device capable of obtaining desired optical and electrical properties by controlling a voltage applied to a liquid crystal material using an electrode of a substrate. Then, by arranging a large number of electrodes in parallel in plan, each can be used as a pixel, and by individually controlling the voltage applied to the pixel, a liquid crystal panel capable of displaying a fine image can be obtained.

Here, the response time of the liquid crystal material to the change of the electric field is the distance between the two substrates (cell gap)
And depending on the type of liquid crystal material, etc., but generally several milliseconds to several tens of milliseconds. Furthermore, when the amount of change in the electric field is small, the response time of the liquid crystal material is further increased. This property causes an obstacle in image display such as afterimage, tailing and a drop in contrast when displaying a moving image by a liquid crystal panel, particularly when changing from half tone to another half tone The degree of the above-mentioned failure becomes remarkable when

On the other hand, as a problem unique to liquid crystal panels using an active matrix, there is a change in write voltage due to constant charge driving. The constant charge drive in the present embodiment will be described below.

The pixel circuit in the active matrix includes a switch that controls writing and a capacitive element that holds a charge. The driving method of the pixel circuit in the active matrix is such that after the switch is turned on and a predetermined voltage is written to the pixel circuit, the switch is immediately turned off to hold the charge in the pixel circuit (hold state). In the hold state, charge exchange is not performed between the inside and the outside of the pixel circuit (constant charge). Generally, the period in which the switch is off is about several hundred times (the number of scanning lines) times longer than the period in which the switch is on. Therefore, the switch of the pixel circuit may be considered to be almost off.
From the above, it is assumed that the constant charge drive in this embodiment is a drive method in which the pixel circuit is in the hold state for most of the time when the liquid crystal panel is driven.

Next, the electrical characteristics of the liquid crystal material will be described. In the liquid crystal material, when the electric field applied from the outside changes, the dielectric properties also change at the same time as the optical properties change. That is, when each pixel of the 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 with the applied voltage. This phenomenon is called dynamic capacitance.

As described above, in the case of driving the capacitive element whose capacitance is changed by the applied voltage by the above-described constant charge driving, the following problems occur. That is, there is a problem that when the capacitance of the liquid crystal element is changed in the hold state in which the charge transfer is not performed, the applied voltage is also changed. This can be understood from the fact that the amount of charge is constant in the relationship of (amount of charge) = (capacitance) × (applied voltage).

For the above reasons, in the liquid crystal panel using the active matrix, the voltage in the hold state is changed from the voltage in the writing state by the constant charge driving. As a result, the transmittance of the liquid crystal element is different from the change in the driving method which does not take the hold state. FIG. 44 shows this state. FIG. 44A shows an example of control of the voltage written to the pixel circuit, with time on the horizontal axis and the absolute value of voltage on the vertical axis. FIG. 44B shows a control example of the voltage written to the pixel circuit in the case where time is taken on the horizontal axis and voltage is taken on the vertical axis. In FIG. 44C, the horizontal axis represents time, and the vertical axis represents the transmittance of the liquid crystal element.
FIG. 44 shows a time change of transmittance of the liquid crystal element in the case where the voltage shown in FIG. 44A or FIG. 44B is written to the pixel circuit. In FIGS. 44A to 44C, a period F represents a voltage rewriting period, and the time to rewrite the voltage is t ₁ , t ₂ , t ₃ , t ₄ ,.
・ We explain as.

Here, the write voltage corresponding to the image data input to the liquid crystal display device is | V ₁ | for rewriting at time 0, | for rewriting at time t ₁ , t ₂ , t ₃ , t ₄ ,.
Suppose that V ₂ |. (See Figure 44 (A))

The polarity of the write voltage corresponding to the image data input to the liquid crystal display device may be switched periodically. (Reversal Driving: See FIG. 44B) By this method, direct current voltage can be applied as little as possible to the liquid crystal, so that burn-in and the like due to deterioration of the liquid crystal element can be prevented. Note that the cycle of switching the polarity (inversion cycle) may be the same as the voltage rewrite cycle. In this case, since the inversion cycle is short, the occurrence of flicker due to the inversion drive can be reduced. Furthermore, the inversion period may be a period that is an integral multiple of the voltage rewriting period. In this case, power consumption can be reduced because the inversion period is long and the frequency can be reduced by changing the polarity to write the voltage.

FIG. 44C shows a time change of transmittance of the liquid crystal element when a voltage as shown in FIG. 44A or FIG. 44B is applied to the liquid crystal element. Here, the voltage to the liquid crystal element | V ₁
Is applied, and the transmittance of the liquid crystal element after a sufficient time has elapsed is taken as TR ₁ . Similarly, a voltage | V ₂ | is applied to the liquid crystal element, and the transmittance of the liquid crystal element after a sufficient time has elapsed is taken 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 as shown by the broken line 30401, Change slowly. For example, the rewriting period of the voltage, when the same as the frame period of the image signal of 60 Hz (16.7 msec), until the transmittance is changed to TR _2, it is necessary to time of several frames.

However, the smooth temporal change in transmittance as shown by the broken line 30401 is when the 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, since the voltage in the hold state is changed from the voltage in the writing state by constant charge driving, the transmittance of the liquid crystal element is a broken line 30401 It does not become a time change as shown in, but instead becomes a step time change as shown by a solid line 30402. This is because the voltage changes due to the constant charge drive, and thus the target voltage can not be reached in one writing. As a result, the response time of the transmittance of the liquid crystal element is apparently longer than the original response time (broken line 30401), and the image display defects such as afterimage, tailing, and contrast deterioration are remarkable. It will cause it.

By using the overdrive driving, it is possible to solve simultaneously the phenomenon that the intrinsic response time of the liquid crystal element and the apparent response time due to the lack of writing by the dynamic capacitance and the constant charge drive are further increased. FIG. 45 shows this state. FIG. 45A shows an example of control of a voltage written to a pixel circuit, where time is plotted on the horizontal axis and absolute value of voltage is plotted on the vertical axis. FIG. 45B shows a control example of the voltage written to the pixel circuit when time is taken on the horizontal axis and voltage is taken on the vertical axis. 45C, the horizontal axis represents time, the vertical axis represents the transmittance of the liquid crystal element, and the voltage represented by FIG. 45A or 45B is written in the pixel circuit. It represents the time change of the transmittance. In FIGS. 45A to 45C, a period F represents a voltage rewriting cycle, and times at which the voltage is rewritten are described as t ₁ , t ₂ , t ₃ , t ₄ , and so on.

Here, the write voltage corresponding to the image data input to the liquid crystal display device is | V ₁ | for rewriting at time 0, | V ₃ | for rewriting at time t ₁ , time t ₂ , t ₃ , t
_In the rewriting in ₄ , ..., it is assumed that | V ₂ |. (Refer to FIG. 45 (A))

The polarity of the write voltage corresponding to the image data input to the liquid crystal display device may be switched periodically. (Reversal Driving: See FIG. 45B) According to this method, direct current voltage can be applied as little as possible to the liquid crystal, so that burn-in and the like due to deterioration of the liquid crystal element can be prevented. Note that the cycle of switching the polarity (inversion cycle) may be the same as the voltage rewrite cycle. In this case, since the inversion cycle is short, the occurrence of flicker due to the inversion drive can be reduced. Furthermore, the inversion period may be a period that is an integral multiple of the voltage rewriting period. In this case, power consumption can be reduced because the inversion period is long and the frequency can be reduced by changing the polarity to write the voltage.

FIG. 45C shows a time change of transmittance of the liquid crystal element when a voltage as shown in FIG. 45A or FIG. 45B is applied to the liquid crystal element. Here, the voltage to the liquid crystal element | V ₁
Is applied, and the transmittance of the liquid crystal element after a sufficient time has elapsed is taken as TR ₁ . Similarly, a voltage | V ₂ | is applied to the liquid crystal element, and the transmittance of the liquid crystal element after a sufficient time has elapsed is taken as TR ₂ . Similarly, the voltage | V ₃ | is applied to the liquid crystal element, and the transmittance of the liquid crystal element after a sufficient time has elapsed is set to TR ₃ . At time _{t 1,} the voltage applied to the liquid crystal element is | _{V 1} | from | V
_When it changes to ₃ |, the transmittance of the liquid crystal element tries to change the transmittance to TR ₃ in several frames, as indicated by the broken line 30501. However, the voltage | _{V 3} | applied at the end at time _{t 2,} later than time _{t 2,} the voltage | _{V 2} | is applied. Therefore, the transmittance of the liquid crystal element is not as shown by a broken line 30501 but as shown by a solid line 30502. here,
It is preferable to set the value of the voltage | V ₃ | so that the transmittance is approximately TR ₂ at time t ₂ . Here, the voltage | V ₃ | is also called an overdrive voltage.

That is, by changing the overdrive voltage | V ₃ |, the response time of the liquid crystal element can be controlled to some extent. This is because the response time of the liquid crystal changes with 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.

Note that it is preferable to change the overdrive voltage | V ₃ | in accordance with the amount of voltage change, that is, the voltages | V ₁ | and | V ₂ | that give the target transmittances TR ₁ and TR _2. . This is because even if the response time of the liquid crystal element is changed by the amount of change in voltage, the optimum response time can always be obtained if the overdrive voltage | V ₃ | is changed accordingly. is there.

The overdrive voltage | V ₃ | is preferably changed according to the mode of liquid crystal such as TN, VA, IPS, OCB. This is because even if the response speed of the liquid crystal varies depending on the mode of the liquid crystal, it is possible to always obtain an optimal response time by changing the overdrive voltage | V ₃ | in accordance therewith.

The voltage rewrite cycle F may be the same as the frame cycle of the input signal. In this case, since the peripheral drive circuit of the liquid crystal display device can be simplified, a liquid crystal display device with low manufacturing cost can be obtained.

The voltage rewrite cycle F may be shorter than the frame cycle of the input signal. For example,
The voltage rewriting period F may be 1/2, 1/3 or less of the frame period of the input signal. It is effective to use this method together with the measures against the deterioration of the moving picture quality caused by the hold drive of the liquid crystal display, such as black insertion drive, backlight blinking, backlight scan, intermediate image insertion drive by motion compensation, etc. is there. That is, since the response time of the liquid crystal element which is required is short, it is relatively easy to use the overdrive driving method described in this embodiment because the response time of the required liquid crystal element is short. The response time of the liquid crystal element can be shortened. Although it is possible to shorten the response time of the liquid crystal element by the cell gap, the liquid crystal material, the liquid crystal mode, etc., it is technically difficult. Therefore, it is very important to use a method for shortening the response time of the liquid crystal element from the driving method such as overdrive.

The voltage rewriting period F may be longer than the frame period of the input signal. For example,
The voltage rewriting period F may be twice, three times or more of the frame period of the input signal. It is effective to use this method in combination with means (circuit) for determining whether or not voltage rewriting is performed for a long time. That is, when the voltage rewriting is not performed for a long time, the operation of the circuit can be stopped during that period by not performing the voltage rewriting operation itself, so that a liquid crystal display device with low power consumption is obtained Can.

Next, a specific method for changing the overdrive voltage | V ₃ | in accordance with the voltages | V ₁ | and | V ₂ | which 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. The signal input to the drive circuit is a voltage | V giving a transmittance TR ₁
A signal relating to ₁ | and a signal relating to a voltage | V ₂ | giving the transmittance TR ₂ , and a signal outputted from the overdrive circuit becomes a signal relating to the overdrive voltage | V ₃ |. Here, as these signals, voltages applied to liquid crystal elements (| V ₁ |, | V ₂ |
, | V ₃ |), or a digital signal for applying a voltage to be applied to the liquid crystal element. Here, the signal related to the overdrive circuit is described as a digital signal.

First, the overall configuration of the overdrive circuit will be described with reference to (A) of FIG. Here, the input image signal 310 is used as a signal for controlling the overdrive voltage.
Use 1a and 3101b. As a result of processing these signals, it is assumed that an output image signal 3104 is output as a signal giving an overdrive voltage.

Here, the voltages │V ₁ │ and │V ₂ │ giving desired transmittances TR ₁ and TR ₂ are
The input image signals 3101 a and 3101 b are also preferably image signals in adjacent frames, since they are image signals in adjacent frames. In order to obtain such a signal, the input image signal 3101a can be input to the delay circuit 3102 in FIG. 46A, and the signal output as a result can be used as the input image signal 3101b. The delay circuit 3102 may be, for example, a memory. That is,
In order to delay the input image signal 3101 a by one frame, the input image signal 3 is stored in the memory.
101a is stored, and at the same time, the signal stored in the previous frame is taken out from the memory as the input image signal 3101b, and the input image signal 3101a and the input image signal 3101b are simultaneously input to the correction circuit 3103. By doing this, it is possible to handle image signals in adjacent frames. Then, an image signal in frames adjacent to each other is input to the correction circuit 3103 to output an image signal 3104.
You can get When a memory is used as the delay circuit 3102, a memory having a capacity capable of storing an image signal of one frame (that is, a frame memory) can be used in order to delay one frame. By doing this, the memory capacity is sufficient.
It can have a function as a delay circuit.

Next, the delay circuit 3102 configured mainly for reducing the memory capacity will be described. By using such a circuit as the delay circuit 3102, the memory capacity can be reduced, so that the manufacturing cost can be reduced.

Specifically, a delay circuit as shown in FIG. 46B can be used as the delay circuit 3102 having such a feature. The delay circuit 3102 shown in (B) of FIG.
105, a memory 3106, and a decoder 3107.

The operation of the delay circuit 3102 shown in FIG. 46 (B) is as follows. First,
Before storing the input image signal 3101a in the memory 3106, the encoder 3105 performs compression processing. This can reduce the size of data to be stored in the memory 3106. As a result, since the memory capacity can be reduced, the manufacturing cost can be reduced. Then, the image signal subjected to the compression processing is decoded by the decoder 3107.
And it is decompressed here. By this, the previous signal compressed by the encoder 3105 can be restored. Here, the compression and decompression processing performed by the encoder 3105 and the decoder 3107 may be reversible processing. By doing this, since the image signal does not deteriorate even after the compression and expansion processing is performed, the memory capacity can be reduced without degrading the quality of the image finally displayed on the device. Furthermore, the compression and decompression processing performed by the encoder 3105 and the decoder 3107 may be irreversible processing. By so doing, the size of the data of the image signal after compression can be made very small, so the memory capacity can be greatly reduced.

Note that various methods other than those described above can be used as a method for reducing the memory capacity. Instead of compressing the image by the encoder, reduce the color information of the image signal (for example, reduce color from 260,000 colors to 65,000 colors), or reduce the number of data (decrease the resolution), etc. Methods can be used.

Next, specific examples of the correction circuit 3103 will be described with reference to (C) to (E) in FIG. The correction circuit 3103 is a circuit for outputting an output image signal of a certain value from two input image signals. Here, when the relationship between the two input image signals and the output image signal is non-linear and it is difficult to obtain by simple calculation, a look-up table (LUT) may be used as the correction circuit 3103. In the LUT, the relationship between the two input image signals and the output image signal is obtained in advance by measurement, so that output image signals corresponding to the two input image signals can be obtained by simply referring to the LUT. By using the LUT 3108 as the correction circuit 3103 (see FIG. 46C), the correction circuit 3103 can be realized without complex circuit design or the like.

Here, since the LUT is one of memories, it is preferable to reduce the memory capacity as much as possible in order to reduce the manufacturing cost. As an example of the correction circuit 3103 for realizing it, the circuit shown in FIG. 46D can be considered. The correction circuit 3103 shown in FIG.
A LUT 3109 and an adder 3110 are included. The LUT 3109 has an input image signal 310.
1a and difference data of an output image signal 3104 to be output are stored. That is, from the input image signal 3101a and the input image signal 3101b, the corresponding difference data is
The difference data extracted from 3109 and the extracted difference data and the input image signal 3101a are added to the adder 31.
By adding 10, an output image signal 3104 can be obtained. Note that the LUT
By using data stored in 3109 as difference data, it is possible to realize reduction in the memory capacity of the LUT. This is because the difference data has a smaller data size than the output image signal 3104 as it is, so the memory capacity required for the LUT 3109 can be reduced.

Furthermore, if the output image signal can be obtained by a simple operation such as arithmetic operation of two input image signals, it can be realized by a combination of simple circuits such as an adder, a subtractor, and a multiplier.
As a result, it is not necessary to use a LUT, and the manufacturing cost can be significantly reduced.
As such a circuit, a circuit shown in (E) of FIG. 46 can be mentioned. Figure 46 (
The correction circuit 3103 shown in E) includes a subtractor 3111, a multiplier 3112 and an adder 3113.
And. First, the difference between the input image signal 3101 a and the input image signal 3101 b is obtained by the subtractor 3111. Thereafter, a multiplier 3112 multiplies the difference value by an appropriate coefficient. Then, a difference value obtained by multiplying the input image signal 3101 a by an appropriate coefficient is added to the adder 311.
The output image signal 3104 can be obtained by adding up by 3. By using such a circuit, it is not necessary to use a LUT, and the manufacturing cost can be significantly reduced.

By using the correction circuit 3103 shown in (E) of FIG.
It is possible to prevent the output of the inappropriate output image signal 3104. The condition is
The difference between the output image signal 3104 giving the overdrive voltage, and the input image signal 3101a and the input image signal 3101b has linearity. Then, the slope of this linearity is taken as a coefficient to be multiplied by the multiplier 3112. That is, it is preferable to use the correction circuit 3103 shown in (E) of FIG. 46 for a liquid crystal element having such a property. As a liquid crystal element having such a property, an IPS mode liquid crystal element having a small dependency of response speed on gradation can be mentioned. Thus, for example, by using the correction circuit 3103 shown in FIG. 46E for the liquid crystal element in the IPS mode, the manufacturing cost can be greatly reduced, and an inappropriate output image signal 3104 is output. An overdrive circuit can be obtained that can be prevented.

Note that functions equivalent to those of the circuits shown in (A) to (E) of FIG. 46 may be realized by software processing. The memory used for the delay circuit may be another memory included in the liquid crystal display device, a memory included in an apparatus on the side of sending out an image to be displayed on the liquid crystal display (for example, a video card etc. included in a personal computer or a similar device). It can be diverted. By this, not only the manufacturing cost can be reduced, but also the user can select the strength of overdrive, the condition to use, etc. according to the preference.

Next, driving for operating the potential of the common line will be described with reference to FIG. Figure 47 of (
A) shows a plurality of pixel circuits when one common line is disposed for one scanning line in a display device using a display element having a capacitive property such as a liquid crystal element FIG. The pixel circuit illustrated in FIG. 47A includes a transistor 3201, an auxiliary capacitor 3202, a display element 3203, a video signal line 3204, a scan line 3205, and a common line 3206.

The gate electrode of the transistor 3201 is electrically connected to the scan line 3205, one of the source electrode and the drain electrode of the transistor 3201 is electrically connected to the video signal line 3204, and the other of the source electrode and the drain electrode of the transistor 3201 is The auxiliary capacity 3202
And one electrode of the display element 3203.
Further, the other electrode of the auxiliary capacitance 3202 is electrically connected to the common line 3206.

First, since the transistor 3201 is turned on in the pixel selected by the scanning line 3205, a voltage corresponding to the video signal is applied to the display element 3203 and the storage capacitor 3202 through the video signal line 3204. At this time, if the video signal is to display the lowest gradation for all the pixels connected to the common line 3206, or the common line 3
In the case where the highest gradation is displayed for all the pixels connected to 206, it is not necessary to write a video signal to each pixel via the video signal line 3204. Video signal line 320
The voltage applied to the display element 3203 can be changed by moving the potential of the common line 3206 instead of writing the video signal through 4.

Next, FIG. 47B shows a display device using a display element having a capacitive property such as a liquid crystal element, in which two common lines are provided for one scanning line, It is a figure showing a plurality of pixel circuits. The pixel circuit illustrated in FIG. 47B includes a transistor 3211, an auxiliary capacitor 3212, a display element 3213, a video signal line 3214, a scan line 3215, and a first common line 3.
216 and a second common line 3217.

The gate electrode of the transistor 3211 is electrically connected to the scan line 3215, one of the source electrode and the drain electrode of the transistor 3211 is electrically connected to the video signal line 3214, and the other of the source electrode and the drain electrode of the transistor 3211 is The auxiliary capacity 3212
It is electrically connected to one of the electrodes and the one of the electrodes of the display element 3213.
The other electrode of the auxiliary capacitance 3212 is electrically connected to the first common line 3216.
Further, in the pixel adjacent to the pixel, the other electrode of the storage capacitor 3212 is electrically connected to the second common line 3217.

The pixel circuit shown in FIG. 47B has a small number of pixels electrically connected to one common line, and therefore, instead of writing a video signal through the video signal line 3214, the first common line 3 is not used.
By changing the potential of the 216 or the second common line 3217, the frequency with which the voltage applied to the display element 3213 can be changed is significantly increased. In addition, source inversion drive or dot inversion drive is possible. The source inversion drive or the dot inversion drive can suppress the flicker while improving the reliability of the element.

Next, a scanning backlight will be described with reference to FIG. FIG. 66A shows a scanning backlight in which cold cathode tubes are juxtaposed. The scanning backlight shown in FIG. 66A includes a diffusion plate 6601 and N cold cathode fluorescent lamps 6602-1 to 6602 -N. By arranging N cold cathode fluorescent lamps 6602-1 to 6602 -N in parallel behind diffusion plate 6601, N cold cathode fluorescent lamps 6602-1 to 6602 -N change their brightness and scan Can.

The change in luminance of each cold cathode tube at the time of scanning will be described using (C) in FIG. First, the luminance of the cold cathode tube 6602-1 is changed for a fixed time. And then, cold cathode tube 660
The brightness of the cold cathode fluorescent tube 6602-2 disposed next to 2-1 is changed by the same time. Thus, the luminance is changed sequentially from the cold cathode fluorescent lamps 6602-1 to 6602 -N. In addition, in (C) of FIG. 66, although the luminance to be changed for a fixed time is set to be smaller than the original luminance, it may be larger than the original luminance. Further, although the cold cathode tubes 6602-1 to 6602 -N are scanned, the cold cathode tubes 6602 -N to 6602-1 may be scanned in the reverse direction.

By driving as shown in FIG. 66, the average luminance of the backlight can be reduced. Therefore, the power consumption of the backlight which occupies most of the power consumption of the liquid crystal display device can be reduced.

Note that an LED may be used as a light source of the scanning backlight. The scanning backlight in that case is as shown in FIG. The scanning backlight shown in FIG. 66B includes a diffusion plate 6611 and light sources 6612-1 to 6612-N in which LEDs are juxtaposed. When an LED is used as a light source of a scanning backlight, there is an advantage that the backlight can be made thin and light. In addition, there is an advantage that the color reproduction range can be expanded. Furthermore, L
The LEDs juxtaposed to each of the ED juxtaposed light sources 6612-1 to 6612 -N can be similarly scanned, and thus can be point-scan backlights. If the point scanning type is used, the image quality of the moving image can be further improved.

In addition, also when using LED as a light source of a backlight, as shown to (C) of FIG. 66, it can drive by changing a brightness | luminance.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of this embodiment can be applied to, combined with, or replaced with the contents (or a part) described in the figure of another embodiment. Can do it freely. Furthermore, in the drawings of the present embodiment, more parts can be configured by combining the parts of the other embodiments with respect to the respective parts.

Note that this embodiment is an example in the case of embodying the contents (may be a part) described in the other embodiments, an example in the case of slight modification, an example in the case of changing a part, an improvement An example of the case,
An example of the case described in detail, an example of the case of application, an example of the relevant part, and the like are shown. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or replaced with this embodiment.

Tenth Embodiment
In the present embodiment, the operation of the display device is described.

FIG. 67 is a diagram showing a configuration example of a display device.

The display device includes a pixel portion 6701, a signal line driver circuit 6703, and a scan line driver circuit 6704. In the pixel portion 6701, a plurality of signal lines S1 to Sm are arranged extending in the column direction from the signal line driver circuit 6703. In the pixel portion 6701, a plurality of scan lines G1 to Gn are arranged so as to extend in the row direction from the scan line driver circuit 6704. The pixels 6702 are arranged in a matrix at the intersections of the plurality of signal lines S1 to Sm and the plurality of scan lines G1 to Gn.

Note that the signal line driver circuit 6703 has a function of outputting a signal to each of the signal lines S1 to Sn. This signal may be called a video signal. Note that the scan line driver circuit 6704 has a function of outputting a signal to each of the scan lines G1 to Gm. This signal may be called a scanning signal.

Note that the pixel 6702 includes at least a switching element connected to a signal line.
The switching element is controlled to be on or off by the potential of the scanning line (scanning signal). Then, the pixel 6702 is selected when the switching element is on, and the pixel 6702 is not selected when the switching element is off.

When the pixel 6702 is selected (selected state), a video signal is input to the pixel 6702 from the signal line. Then, the state of the pixel 6702 (eg, luminance, transmittance, voltage of the storage capacitor, and the like) changes in accordance with the input video signal.

When the pixel 6702 is not selected (in a non-selected state), a video signal is not input to the pixel 6702. However, since the pixel 6702 holds a potential corresponding to the video signal input at the time of selection, the pixel 6702 maintains (for example, luminance, transmittance, voltage of a storage capacitor, or the like) corresponding to the video signal.

Note that the structure of the display device is not limited to that shown in FIG. For example, a wiring (such as a scan line, a signal line, a power supply line, a capacitor line, or a common line) may be newly added depending on the structure of the pixel 6702.
As another example, circuits having various functions may be added.

FIG. 68 shows an example of a timing chart for explaining the operation of the display device.

The timing chart of FIG. 68 shows one frame period corresponding to a period in which an image for one screen is displayed. The period for one frame is not particularly limited, but the person who sees the image flickers (flicker)
It is preferable to set it to at least 1/60 second or less so as not to feel the

In the timing chart of FIG. 68, the scanning line G1 in the first row, the scanning line Gi in the i-th row (scanning line G1
This shows the timing when any one of Gm to Gm, the (i + 1) -th scan line Gi + 1 and the m-th scan line Gm are selected.

Note that at the same time a scan line is selected, a pixel 6702 connected to the scan line is also selected. For example, when the i-th scan line Gi is selected, the pixel 6702 connected to the i-th scan line Gi is also selected.

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

Therefore, when a scan line in a row is selected, a plurality of pixels 670 connected to the scan line is selected.
2, a video signal is input from each of the signal lines G1 to Gm. For example, while the i-th scanning line Gi is selected, a plurality of pixels 67 connected to the i-th scanning line Gi
The signal 02 inputs an arbitrary video signal from each of the signal lines S1 to Sn. Thus, the plurality of individual pixels 6702 can be controlled independently by the scanning signal and the video signal.

Next, the case where one gate selection period is divided into a plurality of sub gate selection periods will be described.
FIG. 69 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).

Note that one gate selection period can be divided into three or more subgate selection periods.

The timing chart of FIG. 69 shows one frame period corresponding to a period in which an image for one screen is displayed. The period for one frame is not particularly limited, but the person who sees the image flickers (flicker)
It is preferable to set it to at least 1/60 second or less so as not to feel the

Note that one frame consists of two subframes (first and second subframes)
It is divided into

The timing chart of FIG. 69 shows the scan line Gi of the i-th row, the scan line Gi + 1, j of the i + 1-th row.
The timing at which the scanning line Gj (any one of the scanning lines Gi + 1 to Gm) in the row, the scanning line in the j + 1th row and the scanning line Gj + 1 in the Gj + 1th row are selected is shown.

Note that at the same time a scan line is selected, a pixel 6702 connected to the scan line is also selected. For example, when the i-th scan line Gi is selected, the pixel 6702 connected to the i-th scan line Gi is also selected.

Each of the scanning lines G1 to Gm is sequentially scanned within each subgate selection period. For example, in a certain one gate selection period, the scan line Gi in the i-th row is selected in the first subgate selection period, and the scan line Gj in the j-th row is selected in the second subgate selection period.
Then, in one gate selection period, it becomes possible to operate as if scanning signals for two rows were simultaneously selected. At this time, separate video signals are input to the signal lines S1 to Sn in the first subgate selection period and the second subgate selection period. Therefore,
A plurality of pixels 6702 connected to the i-th row and a plurality of pixels 670 connected to the j-th row
2 can input separate video signals.

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

In the present embodiment, the input frame rate may not necessarily coincide with the display frame rate. When the input frame rate and the display frame rate are different, the frame rate can be converted by a circuit (frame rate conversion circuit) that converts the frame rate of the image data. By doing this, even when 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 larger than the display frame rate, it is possible to convert to various display frame rates and perform display by discarding part of the input image data.
In this case, since the display frame rate can be reduced, the operating frequency of the drive circuit for displaying 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, all or part of the input image data is displayed a plurality of times, another image is generated from the input image data, and the input image data is It is possible to convert to various display frame rates and perform display by using means such as generating an unrelated image. In this case, the quality of the moving image can be improved by increasing the display frame rate.

In the present 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 in the case where 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 in the case where the input frame rate is smaller than the display frame rate. it can.

In the present 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 that of the basic image and displayed to match the input frame rate with the display frame rate will be referred to as an interpolated image. As the basic image, the same image as the input image data can be used. The same image as the basic image can be used as the interpolation image. Furthermore, an image different from the basic image may be created, and the created image may be used as an interpolation image.

When creating an interpolation image, a method of detecting temporal change (movement of an image) of input image data and using an image in an intermediate state of these as an interpolation image, an image obtained by multiplying the luminance of a basic image by a coefficient A method of making the interpolation image, creating a plurality of different images from the input image data and presenting the plurality of images sequentially in time (one of the plurality of images is used as a basic image,
There is a method of causing the observer to perceive as if the image corresponding to the input image data is displayed by making the remaining the interpolation image). As a method of creating a plurality of different images from the input image data, there are a method of converting gamma values of the input image data, a method of dividing tone values included in the input image data, and the like.

The image in the intermediate state (intermediate image) is an image obtained by detecting a temporal change (movement of the image) of the input image data and interpolating the detected movement. Determining an intermediate image by such a method is referred to as motion compensation.

Next, a specific example of the frame rate conversion method will be described. According to this method, it is possible to realize frame rate conversion of arbitrary rational number (n / m) times. Here, n and m are integers of 1 or more. The frame rate conversion method in the present embodiment can be divided into the first step and the second step and handled. Here, the first step is a step of frame rate conversion to an arbitrary rational number (n / m). Here, a basic image may be used as the interpolation image, or an intermediate image obtained by motion compensation may be used as the interpolation image. In the second step, a plurality of different images (sub-images) are created from the input image data or each frame rate converted image in the first step, and the plurality of sub-images are temporally continuous. Step for performing the display method. By using the method according to the second step, although it is actually displaying a plurality of different images, it can also be perceived visually by the human eye as if the original image was displayed.

In the frame rate conversion method according to the present embodiment, both the first step and the second step may be used, or the first step may be omitted and only the second step may be used. Step 2 may be omitted and only the first step may be used.

First, as the first step, frame rate conversion of arbitrary rational number (n / m) times will be described. (Refer to FIG. 70) In FIG. 70, the horizontal axis is time, and the vertical axis is shown by performing classification on various n and m. The graphic in FIG. 70 represents a schematic view of the displayed image, and the timing at which it is displayed by its lateral position. Furthermore, it is assumed that the movement of the image is schematically represented by the points displayed in the figure. 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 input image data. The period of the input image data corresponds to the input frame rate. For example, when the input frame rate is 60 Hz, the period of input image data is 1/60 seconds. Similarly, if the input frame rate is 50 Hz, then
The cycle of input image data is 1/50 seconds. Thus, the period of the input image data (unit:
Seconds) 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,
48 Hz, 100 Hz, 120 Hz, 140 Hz, etc. can be mentioned. Where 2
4 Hz is a frame rate used for film movies and the like. 50 Hz is a frame rate used for video signals and the like of the PAL standard. The 60 Hz is a frame rate used for a video signal or the like of the NTSC standard. 70 Hz is a frame rate used for a display input signal or the like of a personal computer. 48Hz, 100Hz, 120Hz,
140 Hz is a frame rate twice as high as these. The frame rate is not limited to twice, and may be a frame rate of various multiples. As described above, according to the method described in the present embodiment, frame rate conversion can be realized for input signals of various standards.

The procedure of frame rate conversion of arbitrary rational number (n / m) times in the first step is as follows.
As the procedure 1, the k-th interpolation image for the first basic image (k is an integer of 1 or more; the initial value is 1
Determine the display timing of). It is assumed that the display timing of the k-th interpolation image is a point at which a period obtained by multiplying the cycle of input image data by k (m / n) has passed since the display of the first basic image.
In step 2, it is determined whether the coefficient k (m / n) used to determine the display timing of the k-th 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 k-th interpolation image, and the first step is ended. If it is not an integer, proceed to step 3.
In step 3, an image to be used as the k-th interpolation image is determined. Specifically, the coefficient k (m / n) used to determine the display timing of the k-th interpolation image is converted into the form of x + y / n. Here, x and y are integers, and y is a number smaller than n. Then, when the k-th interpolation image is an intermediate image determined by motion compensation, the k-th interpolation image is
An intermediate image is obtained as an image corresponding to a motion obtained by multiplying the motion of the image from the basic image of (1) to the (x + 2) basic image by (y / n). When the k-th interpolation image is the same as the basic image, the (x + 1) -th basic image can be used. The method of obtaining the intermediate image as an image corresponding to the movement obtained by multiplying the movement of the image by (y / n) will be described in detail in another part.
In step 4, the interpolation image of interest is moved to the next interpolation image. Specifically, the value of k is increased by 1, and the process returns to step 1.

Next, in the procedure in the first step, the values of n and m are specifically shown and described in detail.

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 a mechanism for executing the procedure in the first step is implemented in the device, it is possible to switch the driving method so that the optimum operation according to the situation is performed. Note that the conditions mentioned here are the contents of the image data, the environment inside and outside the device (temperature, humidity, pressure, light, sound, magnetic field, electric field, radiation dose,
Includes altitude, acceleration, travel speed, etc., user settings, software versions, etc. On the other hand, if the mechanism for executing the procedure in the first step is determined in advance at the design stage of the apparatus, the drive circuit optimum for each drive method can be used, and the mechanism is determined. Thus, it is possible to expect a reduction in manufacturing cost due to mass production effects.

When n = 1 and m = 1, that is, when the conversion ratio (n / m) is 1 (where n = 1 and m = 1 in FIG. 70), the operation in the first step is as follows. First, when k = 1, in step 1, the display timing of the first interpolated image with respect to the first basic image is determined. As for the display timing of the first interpolation image, the period of the input image data is k (m (m) after the first basic image is displayed.
It is the time when the period of / n) times or 1 time has passed.

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, since the coefficient k (m / n) is 1, it is an integer. Therefore, at the display timing of the first interpolation image, the (k (m / n) +1) th, ie, the second basic image is displayed, and the first step is ended.

That is, when the conversion ratio is 1, the kth image is a basic image, the (k + 1) th image is a basic image, and the image display cycle is one time of the cycle of the input image data. Do.

As a specific expression, when the conversion ratio is 1 (n / m = 1),
I-th (i is a positive integer) image data,
The (i + 1) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
A method of driving a display device, which sequentially displays the (k + 1) th image at intervals equal to the period of the input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) -th image is displayed according to the (i + 1) -th image data.

Here, when the conversion ratio is 1, since the frame rate conversion circuit can be omitted, there is an advantage that the manufacturing cost can be reduced. Furthermore, when the conversion ratio is 1, it has the advantage that the quality of moving pictures can be improved more than when the conversion ratio is smaller than 1. Furthermore, when the conversion ratio is 1, it has the advantage that power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 1.

When n = 2, m = 1, that is, the conversion ratio (n / m) is 2 (n = 2, m = 1 in FIG. 70), the operation in the first step is as follows. First, when k = 1, in step 1, the display timing of the first interpolated image with respect to the first basic image is determined. As for the display timing of the first interpolation image, the period of the input image data is k (m (m) after the first basic image is displayed.
At this point, a period obtained by multiplying / n) times, that is, 1⁄2 times, 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, since the coefficient k (m / n) is 1/2, it is not an integer. Therefore, the procedure goes to step 3.

In step 3, an image to be used as a first interpolation image is determined. Therefore, the factor 1/2 is x
Convert to + y / n form. In the case of the coefficient 1⁄2, x = 0 and y = 1. Then, when the first interpolation image is an intermediate image determined by motion compensation, the first interpolation image is
1) That is, an intermediate image is obtained as an image corresponding to a motion obtained by multiplying the movement of the image from the first basic image to the (x + 2) th, ie, the second basic image by y / n times or 1/2 times. First
When making the interpolation image of the same image as the basic image, the (x + 1) th basic image, ie, the first basic image can be used.

According to the procedure up to this point, the display timing of the first interpolation image and the image to be displayed as the first interpolation image can be determined. Next, in step 4, the interpolation image of interest is transferred from the first interpolation image to the second interpolation image. That is, change k from 1 to 2 and return to step 1.

When k = 2, procedure 1 determines the display timing of the second interpolation image with respect to the first basic image. The display timing of the second interpolation image is a point at which a period obtained by multiplying the period of the input image data by k (m / n), that is, by one, has elapsed since the display of the first basic image.

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, since the coefficient k (m / n) is 1, it is an integer. Therefore, at the display timing of the second interpolation image, the (k (m / n) +1) th, ie, the second basic image is displayed, and the first step is ended.

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

Specifically, when the conversion ratio is 2 (n / m = 2),
I-th (i is a positive integer) image data,
The (i + 1) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
A method of driving a display device, which sequentially displays the (k + 2) th image at an interval of 1/2 times the period of the input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) -th image is displayed according to image data corresponding to a motion obtained by halving the motion from the i-th image data to the (i + 1) -th image data.
The (k + 2) -th image is displayed according to the (i + 1) -th image data.

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

Specifically, when the conversion ratio is 2, it is also called double speed driving or simply double speed driving.
For example, if the input frame rate is 60 Hz, the display frame rate is
120 Hz drive). And an image will be displayed twice continuously with respect to one input image. At this time, when the interpolation image is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. Furthermore, when the display device is an active matrix liquid crystal display device,
In particular, the image quality improvement effect is remarkable. This relates to the problem of insufficient writing voltage due to so-called dynamic capacitance, in which the capacitance of the liquid crystal element fluctuates due to the applied voltage. That is, by making the display frame rate larger than the input frame rate, the frequency of the image data writing operation can be increased, so that the failure such as the tailing of the moving image and the afterimage caused by the shortage of the writing voltage due to the dynamic capacitance is reduced. be able to. Furthermore, it is also effective to combine the AC drive and the 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 AC drive to an integral multiple or an integral fraction of it (for example, 30 Hz, 60 Hz, 120 Hz, 240 Hz, etc.) It can be reduced to an extent that is not perceived by human eyes.

In the case of n = 3, m = 1, that is, when the conversion ratio (n / m) is 3 (where n = 3, m = 1 in FIG. 70), the operation in the first step is as follows. First, when k = 1, in step 1, the display timing of the first interpolated image with respect to the first basic image is determined. As for the display timing of the first interpolation image, the period of the input image data is k (m (m) after the first basic image is displayed.
At this point, a period obtained by multiplying / n) times or 1/3 times 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, since the coefficient k (m / n) is 1/3, it is not an integer. Therefore, the procedure goes to step 3.

In step 3, an image to be used as a first interpolation image is determined. Therefore, the factor 1/3 is x
Convert to + y / n form. In the case of the coefficient 1/3, x = 0 and y = 1. Then, when the first interpolation image is an intermediate image determined by motion compensation, the first interpolation image is
1) That is, an intermediate image is obtained as an image corresponding to a motion obtained by multiplying the motion of the image from the first basic image to the (x + 2) th, ie, the second basic image by y / n times or 1/3 times. First
When making the interpolation image of the same image as the basic image, the (x + 1) th basic image, ie, the first basic image can be used.

According to the procedure up to this point, the display timing of the first interpolation image and the image to be displayed as the first interpolation image can be determined. Next, in step 4, the interpolation image of interest is transferred from the first interpolation image to the second interpolation image. That is, change k from 1 to 2 and return to step 1.

When k = 2, procedure 1 determines the display timing of the second interpolation image with respect to the first basic image. The display timing of the second interpolation image is a point at which a period obtained by multiplying the cycle of the input image data by k (m / n), that is, 2/3, has passed since the display of the first basic image.

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, since the coefficient k (m / n) is 2/3, it is not an integer. Therefore, the procedure goes to step 3.

In step 3, an image to be used as a second interpolation image is determined. Therefore, the factor 2/3 x
Convert to + y / n form. In the case of coefficient 2/3, x = 0 and y = 2. Then, when the second interpolation image is an intermediate image obtained by motion compensation, the second interpolation image is
1) That is, an intermediate image is obtained as an image corresponding to a motion obtained by multiplying the movement of the image from the first basic image to the (x + 2) th, ie, the second basic image by y / n times or 2/3 times. Second
When making the interpolation image of the same image as the basic image, the (x + 1) th basic image, ie, the first basic image can be used.

According to the procedure up to this point, the display timing of the second interpolation image and the image to be displayed as the second interpolation image can be determined. Next, in step 4, the interpolation image of interest is transferred from the second interpolation image to the third interpolation image. That is, change k from 2 to 3 and return to step 1.

When k = 3, in step 1, the display timing of the third interpolated image with respect to the first basic image is determined. The display timing of the third interpolation image is a point at which a period obtained by multiplying the period of the input image data by k (m / n), that is, by one, has elapsed since the display of the first basic image.

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

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

Specifically, when the conversion ratio is 3 (n / m = 3),
I-th (i is a positive integer) image data,
The (i + 1) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
A driving method of a display device for sequentially displaying an image of (k + 3) at intervals of 1/3 times of a cycle of input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the ith image data to the (i + 1) th image data by 1/3.
The (k + 2) -th image is displayed according to image data corresponding to a motion obtained by multiplying the motion from the i-th image to the i + 1-th image by 2/3.
The (k + 3) th image is displayed according to the (i + 1) th image data.

As still another specific expression, when the conversion ratio is 3 (n / m = 3),
I-th (i is a positive integer) image data,
The (i + 1) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
A driving method of a display device for sequentially displaying an image of (k + 3) at intervals of 1/3 times of a cycle of input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to the ith image data,
The (k + 2) th image is displayed according to the ith image data,
The (k + 3) th image is displayed according to the (i + 1) th image data.

Here, when the conversion ratio is 3, there is an advantage that the quality of moving pictures can be improved more than when the conversion ratio is smaller than 3. Furthermore, when the conversion ratio is 3, it has the advantage that power consumption and manufacturing cost can be reduced more than when the conversion ratio is greater than 3.

Specifically, when the conversion ratio is 3, it is also called triple speed driving. For example, if the input frame rate is 60 Hz, the display frame rate is 180 Hz (180 Hz drive). Then, an image is displayed three times consecutively for one input image. At this time, when the interpolation image is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, AC drive of the liquid crystal display and 180 Hz
It is also effective to combine the drive. That is, the driving frequency of the liquid crystal display device is 180H.
while the frequency of the AC drive is an integral multiple or an integer fraction (eg, 45 Hz, 9
By setting the frequency to 0 Hz, 180 Hz, 360 Hz, etc.), it is possible to reduce flicker that appears due to AC drive to an extent that human eyes do not perceive it.

n = 3, m = 2, that is, the conversion ratio (n / m) is 3/2 (n = 3, m = 2 in FIG. 70)
In this case, the operation in the first step is as follows. First, when k = 1, step 1
Then, the display timing of the first interpolation image with respect to the first basic image is determined. The display timing of the first interpolation image is set to k cycles of the input image data after the first basic image is displayed.
It is the time when the (m / n) times, that is, the 2/3 times, 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, since the coefficient k (m / n) is 2/3, it is not an integer. Therefore, the procedure goes to step 3.

In step 3, an image to be used as a first interpolation image is determined. Therefore, the factor 2/3 x
Convert to + y / n form. In the case of coefficient 2/3, x = 0 and y = 2. Then, when the first interpolation image is an intermediate image determined by motion compensation, the first interpolation image is
1) That is, an intermediate image is obtained as an image corresponding to a motion obtained by multiplying the movement of the image from the first basic image to the (x + 2) th, ie, the second basic image by y / n times or 2/3 times. First
When making the interpolation image of the same image as the basic image, the (x + 1) th basic image, ie, the first basic image can be used.

According to the procedure up to this point, the display timing of the first interpolation image and the image to be displayed as the first interpolation image can be determined. Next, in step 4, the interpolation image of interest is transferred from the first interpolation image to the second interpolation image. That is, change k from 1 to 2 and return to step 1.

When k = 2, procedure 1 determines the display timing of the second interpolation image with respect to the first basic image. The display timing of the second interpolation image is a point at which a period obtained by multiplying the period of the input image data by k (m / n), that is, 4/3, has elapsed since the display of the first basic image.

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, since the coefficient k (m / n) is 4/3, it is not an integer. Therefore, the procedure goes to step 3.

In step 3, an image to be used as a second interpolation image is determined. For that, x coefficient 4/3
Convert to + y / n form. In the case of the coefficient 4/3, x = 1 and y = 1. Then, when the second interpolation image is an intermediate image obtained by motion compensation, the second interpolation image is
1) That is, an intermediate image is obtained as an image corresponding to a motion obtained by multiplying the movement of the image from the second basic image to the (x + 2) th, ie, the third basic image by y / n times or 1/3 times. Second
When making the interpolation image of the same image as the basic image, the (x + 1) th or second basic image can be used.

According to the procedure up to this point, the display timing of the second interpolation image and the image to be displayed as the second interpolation image can be determined. Next, in step 4, the interpolation image of interest is transferred from the second interpolation image to the third interpolation image. That is, change k from 2 to 3 and return to step 1.

When k = 3, in step 1, the display timing of the third interpolated image with respect to the first basic image is determined. The display timing of the third interpolation image is a point at which a period obtained by multiplying the cycle of the input image data by k (m / n), that is, twice, has passed since the display of the first basic image.

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

That is, when the conversion ratio is 3/2 (n / m = 3/2),
The kth image is a basic image,
The (k + 1) th image is an interpolated image,
The (k + 2) th image is an interpolated image,
The (k + 3) th image is a basic image, and 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),
I-th (i is a positive integer) image data,
And the (i + 1) th image data,
The (i + 2) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
It is a driving method of a display device for sequentially displaying an image of (k + 3) at an interval of 2/3 times a cycle of input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the ith image data to the (i + 1) th image data by 2/3.
The (k + 2) -th image has a 1/3 movement from the (i + 1) -th image to the (i + 2) -th image.
Displayed according to the image data corresponding to the doubled movement,
The (k + 3) th image is displayed according to the (i + 2) th image data.

As still another specific expression, when the conversion ratio is 3/2 (n / m = 3/2),
I-th (i is a positive integer) image data,
And the (i + 1) th image data,
The (i + 2) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
It is a driving method of a display device for sequentially displaying an image of (k + 3) at an interval of 2/3 times a cycle of input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to the ith image data,
The (k + 2) th image is displayed according to the (i + 1) th image data,
The (k + 3) th image is displayed according to the (i + 2) th image data.

Here, when the conversion ratio is 3/2, there is an advantage that the quality of moving pictures can be improved more than when the conversion ratio is smaller than 3/2. Furthermore, if the conversion ratio is 3/2, the conversion ratio is 3 /
It has the advantage that power consumption and manufacturing cost can be reduced more than the case of larger than two.

Specifically, when the conversion ratio is 3/2, it is also called 3 / 2-speed drive or 1.5-speed drive. For example, if the input frame rate is 60 Hz, the display frame rate is 90
It is Hz (90 Hz drive). Then, the image is displayed three times consecutively for two input images. At this time, when the interpolation image is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. In particular, compared to the drive method with a large drive frequency such as 120 Hz drive (double speed drive) and 180 Hz drive (3 × speed drive), the motion frequency of the circuit for obtaining an intermediate image can be reduced by motion compensation. , Manufacturing cost and power consumption can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided.
The image quality improvement effect is particularly remarkable with respect to a failure such as an afterimage. Furthermore, it is also effective to combine AC drive and 90 Hz drive of the liquid crystal display device. That is, while setting the drive frequency of the liquid crystal display device to 90 Hz, the frequency of the AC drive is an integral multiple or an integer fraction (for example, 3
By setting the frequency to 0 Hz, 45 Hz, 90 Hz, 180 Hz, etc.), it is possible to reduce flicker that appears due to AC drive to such an extent that human eyes do not perceive it.

Although details of the procedure are omitted for positive integers n and m other than the above, the conversion ratio may be set as an arbitrary rational number (n / m) according to the procedure of frame rate conversion in the first step. it can. Among the combinations of positive integers n and m, the conversion ratio (n /
For combinations where m) can be reduced, conversion ratios after reduction can be handled in the same manner.

For example, in the case of n = 4, m = 1, that is, when the conversion ratio (n / m) is 4 (n = 4, m = 1 in FIG. 70),
The kth image is a basic image,
The (k + 1) th image is an interpolated image,
The (k + 2) th image is an interpolated image,
The (k + 3) th image is an interpolated image,
The (k + 4) th image is a basic image, and the image display cycle is characterized by being 1⁄4 of the cycle of the input image data.

More specifically, when the conversion ratio is 4 (n / m = 4),
I-th (i is a positive integer) image data,
The (i + 1) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
With the k + 3 image,
A driving method of a display device for sequentially displaying an image of (k + 4) at an interval of 1⁄4 of a cycle of input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the ith image data to the (i + 1) th image data by 1/4.
The (k + 2) -th image is displayed according to image data corresponding to a motion obtained by halving the motion from the i-th image data to the (i + 1) -th image data.
The (k + 3) th image is displayed according to image data corresponding to a motion obtained by multiplying the motion from the ith image data to the (i + 1) th image data by 3/4.
The (k + 4) th image is displayed according to the (i + 1) th image data.

As still another specific expression, when the conversion ratio is 4 (n / m = 4),
I-th (i is a positive integer) image data,
The (i + 1) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
With the k + 3 image,
A driving method of a display device for sequentially displaying an image of (k + 4) at an interval of 1⁄4 of a cycle of input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to the ith image data,
The (k + 2) th image is displayed according to the ith image data,
The (k + 3) th image is displayed according to the ith image data,
The (k + 4) th image is displayed according to the (i + 1) th image data.

Here, when the conversion ratio is 4, there is an advantage that the quality of moving pictures can be improved more than when the conversion ratio is smaller than 4. Furthermore, when the conversion ratio is 4, it has the advantage that power consumption and manufacturing cost can be reduced more than when the conversion ratio is greater 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). And an image will be displayed continuously 4 times with respect to one input image. At this time, when the interpolation image is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. In particular, 120
As compared with a drive method with a small drive frequency such as Hz drive (double speed drive) and 180 Hz drive (3 × speed drive), an intermediate image obtained by motion compensation with higher accuracy can be used as an interpolation image. The motion can be smoothed and the quality of moving pictures can be significantly improved. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, it is also effective to combine the AC drive and the 240 Hz drive of the 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 integral multiple or an integer fraction (for example, 30 Hz, 40 Hz, 60 Hz, 120 Hz, etc.) It can be reduced to an extent that is not perceived by human eyes.

Further, for example, n = 4 and m = 3, that is, the conversion ratio (n / m) is 4/3 (n in FIG. 70).
In the case of 4, m = 3),
The kth image is a basic image,
The (k + 1) th image is an interpolated image,
The (k + 2) th image is an interpolated image,
The (k + 3) th image is an interpolated image,
The (k + 4) th image is a basic image, and the image display cycle is characterized by being 3/4 times the cycle of the input image data.

More specifically, when the conversion ratio is 4/3 (n / m = 4/3),
I-th (i is a positive integer) image data,
And the (i + 1) th image data,
And the (i + 2) th image data,
The (i + 3) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
With the k + 3 image,
A driving method of a display device for sequentially displaying an image of (k + 4) at an interval of 3⁄4 of a cycle of input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the ith image data to the (i + 1) th image data by 3/4.
The (k + 2) -th image is half the motion from the (i + 1) -th image to the (i + 2) -th image.
Displayed according to the image data corresponding to the doubled movement,
The (k + 3) th image has a 1/4 movement from the (i + 2) th image to the (i + 3) th image.
Displayed according to the image data corresponding to the doubled movement,
The (k + 4) th image is displayed according to the (i + 3) th image data.

As still another specific expression, when the conversion ratio is 4/3 (n / m = 4/3),
I-th (i is a positive integer) image data,
And the (i + 1) th image data,
And the (i + 2) th image data,
The (i + 3) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
With the k + 3 image,
A driving method of a display device for sequentially displaying an image of (k + 4) at an interval of 3⁄4 of a cycle of input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to the ith image data,
The (k + 2) th image is displayed according to the (i + 1) th image data,
The (k + 3) th image is displayed according to the (i + 2) th image data,
The (k + 4) th image is displayed according to the (i + 3) th image data.

Here, when the conversion ratio is 4/3, it has an advantage that the quality of moving pictures can be improved more than when the conversion ratio is smaller than 4/3. Furthermore, if the conversion ratio is 4/3, the conversion ratio is 4 /
It has the advantage that power consumption and manufacturing cost can be reduced compared with the case of greater than three.

Specifically, when the conversion ratio is 4/3, it is also called 4/3 double speed drive or 1.25 double speed drive. For example, if the input frame rate is 60 Hz, the display frame rate is 8
It is 0 Hz (80 Hz drive). Then, images are displayed four times consecutively for three input images. At this time, when the interpolation image is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. In particular, compared to the drive method with a large drive frequency such as 120 Hz drive (double speed drive) and 180 Hz drive (3 × speed drive), the motion frequency of the circuit for obtaining an intermediate image can be reduced by motion compensation. , Manufacturing cost and power consumption can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, it is also effective to combine the AC drive and the 80 Hz drive of the liquid crystal display device. That is, while the driving frequency of the liquid crystal display device is 80 Hz, the frequency of AC driving is an integral multiple or an integer fraction of that (for example,
By setting the frequency to 40 Hz, 80 Hz, 160 Hz, 240 Hz, etc.), it is possible to reduce flicker that appears due to AC drive to such an extent that human eyes do not perceive it.

Further, for example, n = 5, m = 1, that is, the conversion ratio (n / m) is 5 (n = 5 in FIG. 70,
In the case of m = 1),
The kth image is a basic image,
The (k + 1) th image is an interpolated image,
The (k + 2) th image is an interpolated image,
The (k + 3) th image is an interpolated image,
The (k + 4) th image is an interpolated image,
The (k + 5) th image is a basic image, and the image display period is 1⁄5 of the period of the input image data.

More specifically, when the conversion ratio is 5 (n / m = 5),
I-th (i is a positive integer) image data,
The (i + 1) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
With the k + 3 image,
With the k + 4 image,
It is a driving method of a display device for sequentially displaying the (k + 5) th image at an interval of 1⁄5 times the period of the input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the ith image data to the (i + 1) th image data by 1/5.
The (k + 2) -th image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the ith image data to the (i + 1) th image data by 2/5.
The (k + 3) th image is displayed according to image data corresponding to a motion obtained by multiplying the motion from the ith image data to the (i + 1) th image data by 3/5.
The (k + 4) th image is displayed according to image data corresponding to a motion obtained by multiplying the motion from the ith image data to the (i + 1) th image data by 4/5.
The (k + 5) th image is displayed according to the (i + 1) th image data.

As still another specific expression, when the conversion ratio is 5 (n / m = 5),
I-th (i is a positive integer) image data,
The (i + 1) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
With the k + 3 image,
With the k + 4 image,
It is a driving method of a display device for sequentially displaying the (k + 5) th image at an interval of 1⁄5 times the period of the input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to the ith image data,
The (k + 2) th image is displayed according to the ith image data,
The (k + 3) th image is displayed according to the ith image data,
The (k + 4) th image is displayed according to the ith image data,
The (k + 5) th image is displayed according to the (i + 1) th image data.

Here, when the conversion ratio is 5, there is an advantage that the quality of moving pictures can be improved more than when the conversion ratio is smaller than 5. Furthermore, when the conversion ratio is 5, it has the advantage that power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 5.

Specifically, when the conversion ratio is 5, it is also called 5 × speed driving. For example, if the input frame rate is 60 Hz, the display frame rate is 300 Hz (300 Hz drive). Then, the image is continuously displayed five times for one input image. At this time, when the interpolation image is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. In particular, 120
As compared with a drive method with a small drive frequency such as Hz drive (double speed drive) and 180 Hz drive (3 × speed drive), an intermediate image obtained by motion compensation with higher accuracy can be used as an interpolation image. The motion can be smoothed and the quality of moving pictures can be significantly improved. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, it is also effective to combine the AC drive and the 300 Hz drive of the liquid crystal display device. That is, by setting the drive frequency of the liquid crystal display device to 300 Hz and setting the frequency of AC drive to an integral multiple or an integer fraction (for example, 30 Hz, 50 Hz, 60 Hz, 100 Hz, etc.) It can be reduced to an extent that is not perceived by human eyes.

Further, for example, n = 5, m = 2, that is, the conversion ratio (n / m) is 5/2 (n in FIG. 70).
In the case of 5, m = 2))
The kth image is a basic image,
The (k + 1) th image is an interpolated image,
The (k + 2) th image is an interpolated image,
The (k + 3) th image is an interpolated image,
The (k + 4) th image is an interpolated image,
The (k + 5) th image is a basic image, and the image display period is 1⁄5 of the period of the input image data.

More specifically, when the conversion ratio is 5/2 (n / m = 5/2),
I-th (i is a positive integer) image data,
And the (i + 1) th image data,
The (i + 2) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
With the k + 3 image,
With the k + 4 image,
It is a driving method of a display device for sequentially displaying the (k + 5) th image at an interval of 1⁄5 times the period of the input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to image data corresponding to a movement obtained by multiplying the movement from the ith image data to the (i + 1) th image data by 2/5.
The (k + 2) -th image is displayed according to image data corresponding to a motion obtained by multiplying the motion from the i-th image data to the (i + 1) -th image data by 4/5.
The (k + 3) th image is displayed according to image data corresponding to a motion obtained by multiplying the motion from the (i + 1) th image data to the (i + 2) th image data by 1/5.
The (k + 4) th image is displayed according to image data corresponding to a motion obtained by multiplying the motion from the (i + 1) th image data to the (i + 2) th image data by 3/5.
The (k + 5) th image is displayed according to the (i + 2) th image data.

As still another specific expression, when the conversion ratio is 5/2 (n / m = 5/2),
I-th (i is a positive integer) image data,
And the (i + 1) th image data,
The (i + 2) th image data is sequentially input as input image data in a fixed cycle,
The kth (k is a positive integer) image,
The kth +1 image,
And the k + 2 image,
With the k + 3 image,
With the k + 4 image,
It is a driving method of a display device for sequentially displaying the (k + 5) th image at an interval of 1⁄5 times the period of the input image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) th image is displayed according to the ith image data,
The (k + 2) th image is displayed according to the ith image data,
The (k + 3) th image is displayed according to the (i + 1) th image data,
The (k + 4) th image is displayed according to the (i + 1) th image data,
The (k + 5) th image is displayed according to the (i + 2) th image data.

Here, when the conversion ratio is 5/2, it has an advantage that the quality of moving pictures can be improved more than when the conversion ratio is smaller than 5/2. Furthermore, when the conversion ratio is 5/2, it has the advantage that power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 5.

Specifically, when the conversion ratio is 5, it is also referred to as 5 / 2-speed drive or 2.5-speed drive. For example, if the input frame rate is 60 Hz, the display frame rate is 150 H
z (150 Hz drive). Then, the image is displayed five times consecutively for two input images. At this time, when the interpolation image is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. In particular, as compared with a drive method with a small drive frequency such as 120 Hz drive (double-speed drive), an intermediate image obtained by motion compensation with higher accuracy can be used as an interpolation image, so the motion of moving pictures is smoothed further. It is possible to significantly improve the quality of moving pictures. Furthermore, as compared with a driving method with a large driving frequency such as 180 Hz driving (3 × speed driving), the operation frequency of the circuit for obtaining an intermediate image can be reduced by motion compensation, so inexpensive circuits can be used, manufacturing cost and power consumption It can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, it is also effective to combine the AC drive and the 150 Hz drive of the liquid crystal display device. That is, the driving frequency of the liquid crystal display device is
While the frequency of the AC drive is an integral multiple or an integer fraction (eg, 30 Hz, 50
By setting the frequency to Hz, 75 Hz, 150 Hz, etc.), it is possible to reduce flicker that appears due to AC drive to an extent that it is not perceived by human eyes.

Thus, by setting the positive integers n and m variously, the conversion ratio can be set as an arbitrary rational number (n / m). Although detailed description is omitted, in the range where n is 10 or less,
n = 1, m = 1, that is, conversion ratio (n / m) = 1 (1 × driving, 60 Hz),
n = 2, m = 1, that is, conversion ratio (n / m) = 2 (double speed driving, 120 Hz),
n = 3, m = 1, that is, conversion ratio (n / m) = 3 (3 × speed drive, 180 Hz),
n = 3, m = 2, that is, conversion ratio (n / m) = 3/2 (3 / 2-speed drive, 90 Hz),
n = 4, m = 1, that is, conversion ratio (n / m) = 4 (quadruple speed drive, 240 Hz),
n = 4, m = 3, that is, conversion ratio (n / m) = 4/3 (4/3 speed drive, 80 Hz),
n = 5, m = 1, that is, conversion ratio (n / m) = 5/1 (5-fold speed drive, 300 Hz),
n = 5, m = 2, that is, conversion ratio (n / m) = 5/2 (5 / 2-speed drive, 150 Hz),
n = 5, m = 3, that is, conversion ratio (n / m) = 5/3 (5 / 3-speed drive, 100 Hz),
n = 5, m = 4, that is, conversion ratio (n / m) = 5/4 (5 / 4-speed drive, 75 Hz),
n = 6, m = 1, that is, conversion ratio (n / m) = 6 (6-fold speed drive, 360 Hz),
n = 6, m = 5, that is, conversion ratio (n / m) = 6/5 (6/5 speed drive, 72 Hz),
n = 7, m = 1, that is, conversion ratio (n / m) = 7 (7 × driving, 420 Hz),
n = 7, m = 2, that is, conversion ratio (n / m) = 7/2 (7 / 2-speed drive, 210 Hz),
n = 7, m = 3, that is, conversion ratio (n / m) = 7/3 (7/3 speed drive, 140 Hz),
n = 7, m = 4, that is, conversion ratio (n / m) = 7/4 (7/4 speed drive, 105 Hz),
n = 7, m = 5, that is, conversion ratio (n / m) = 7/5 (7/5 double speed drive, 84 Hz),
n = 7, m = 6, that is, conversion ratio (n / m) = 7/6 (7/6 speed drive, 70 Hz),
n = 8, m = 1, that is, conversion ratio (n / m) = 8 (8 × driving, 480 Hz),
n = 8, m = 3, that is, conversion ratio (n / m) = 8/3 (8 / 3-speed drive, 160 Hz),
n = 8, m = 5, that is, conversion ratio (n / m) = 8/5 (8/5 speed drive, 96 Hz),
n = 8, m = 7, that is, conversion ratio (n / m) = 8/7 (8/7 double speed drive, 68.6 Hz)
,
n = 9, m = 1, that is, conversion ratio (n / m) = 9 (9 × driving, 540 Hz),
n = 9, m = 2, that is, conversion ratio (n / m) = 9/2 (9 / 2-speed drive, 270 Hz),
n = 9, m = 4, that is, conversion ratio (n / m) = 9/4 (9/4 speed drive, 135 Hz),
n = 9, m = 5, that is, conversion ratio (n / m) = 9/5 (9 / 5-speed drive, 108 Hz),
n = 9, m = 7, that is, conversion ratio (n / m) = 9/7 (9/7 double speed drive, 77.1 Hz)
,
n = 9, m = 8, ie conversion ratio (n / m) = 9/8 (9/8 double speed drive, 67.5 Hz)
,
n = 10, m = 1, that is, conversion ratio (n / m) = 10 (10 × speed drive, 600 Hz),
n = 10, m = 3, that is, conversion ratio (n / m) = 10/3 (10/3 speed drive, 200 H
z),
n = 10, m = 7, that is, conversion ratio (n / m) = 10/7 (10/7 double speed drive, 85.7)
Hz),
n = 10, m = 9, that is, conversion ratio (n / m) = 10/9 (10/9 double speed drive, 66.7)
Hz),
Combinations of the above are conceivable. Note that the notation of frequency is an example when the input frame rate is 60 Hz, and for other input frame rates, a value obtained by integrating each conversion ratio with the input frame rate is the drive frequency.

In the case where n is an integer greater than 10, although the specific n and m numbers are not listed, the frame rate conversion procedure in the first step can be applied to various n and m. Is clear.

Note that the conversion ratio can be determined depending on how much of the displayed image is an image that can be displayed without performing motion compensation in the input image data. Specifically, as m is smaller, the proportion of images that can be displayed without performing motion compensation on the input image data is larger. If the frequency of motion compensation is low, the frequency of operation of the circuit that performs motion compensation can be reduced, so that the power consumption can be reduced. Furthermore, an image including an error due to motion compensation (the motion of the image is accurately reflected) Image quality can be improved because the possibility of creating an intermediate image) can be reduced. Such conversion ratio is, for example, 1, 2, 3, 3/2, 4, in the range where n is 10 or less.
5,5 / 2,6,7,7 / 2,8,9,9 / 2,10 are mentioned. By using such a conversion ratio, it is possible to increase the quality of the image and reduce the power consumption, particularly when using an intermediate image obtained by motion compensation as the interpolation 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 (only 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 input image data is large (equal to the total number of input image data), and motion compensation is not performed. is there. On the other hand, as m is larger, it is possible to use an intermediate image created by highly accurate motion compensation, and thus has an advantage that the motion of the image can be smoother.

Note that when the display device is a liquid crystal display device, the conversion ratio can be determined in accordance with the response time of the liquid crystal element. Here, the response time of the liquid crystal element is the time from the change of the voltage applied to the liquid crystal element to the response of the liquid crystal element. In the case where the response time of the liquid crystal element differs depending on the amount of change in voltage applied to the liquid crystal element, an average value of the response times of a plurality of representative voltage changes can be used. Alternatively, the response time of the liquid crystal element is MPRT (Movin
g Picture Response Time) may be defined.
Then, by frame rate conversion, the conversion ratio can be determined such that the image display cycle becomes 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 integrating the period of the input image data and the reciprocal of the conversion ratio to a half value of this value. By doing this, the image display cycle can be made 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 driving) can be performed. This is because the image display cycle of the 120 Hz drive is about 8 milliseconds and half of the image display cycle 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 driving) can be performed, and the response time of the liquid crystal element is 5
In the case of milliseconds or more and 11 milliseconds or less, 1.5 × speed driving (90 Hz driving) can be performed, and in the case where the response time of the liquid crystal element is 2 milliseconds or more and 4 milliseconds or less, quadruple speed driving (240 Hz driving) And when the response time of the liquid crystal element is 6 ms or more and 12 ms or less, 1).
. It can be 25 × speed drive (80 Hz drive). The same applies to the other drive frequencies.

The conversion ratio can also be determined by the trade-off between the quality of the moving image and the power consumption and the manufacturing cost. That is, while the quality of moving pictures can be improved by increasing the conversion ratio, the power consumption and the manufacturing cost can be reduced by decreasing the conversion ratio. That is, each conversion ratio in the range where n is 10 or less has the following advantages.

When the conversion ratio is 1, the moving picture quality can be improved more than when the conversion ratio is smaller than 1, and power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 1. Furthermore, since m is small, high image quality can be obtained, and power consumption can be reduced. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 1 time of the cycle of input image data.

When the conversion ratio is 2, the moving picture quality can be improved more than when the conversion ratio is smaller than 2, and power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 2. Furthermore, since m is small, high image quality can be obtained, and power consumption can be reduced. Furthermore, the image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately half of the cycle of the input image data.

When the conversion ratio is 3, the quality of moving pictures can be improved more than when the conversion ratio is smaller than 3, and power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 3. Furthermore, since m is small, high image quality can be obtained, and power consumption can be reduced. Furthermore, the image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is about 1⁄3 of the cycle of the input image data.

When the conversion ratio is 3/2, the moving picture quality can be improved more than when the conversion ratio is smaller than 3/2, and power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 3/2. Furthermore, since m is small, high image quality can be obtained, and power consumption can be reduced. Furthermore, the image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 2/3 of the cycle of the input image data.

When the conversion ratio is 4, the moving picture quality can be improved more than when the conversion ratio is smaller than 4, and power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 4. Furthermore, since m is small, high image quality can be obtained, and power consumption can be reduced. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 1⁄4 of the cycle of the input image data.

When the conversion ratio is 4/3, the moving picture quality can be improved more than when the conversion ratio is smaller than 4/3, and power consumption and manufacturing cost can be reduced as compared with the conversion ratio larger than 4/3. Furthermore, since m is large, the motion of the image can be smoother. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 3⁄4 of the cycle of the input image data.

When the conversion ratio is 5, the moving picture quality can be improved more than when the conversion ratio is smaller than 5, and the power consumption and the manufacturing cost can be reduced more than when the conversion ratio is larger than 5. Furthermore, since m is small, high image quality can be obtained, and power consumption can be reduced. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 1⁄5 of the period of the input image data.

When the conversion ratio is 5/2, the quality of moving pictures can be improved more than when the conversion ratio is smaller than 5/2, and power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 5/2. Furthermore, since m is small, high image quality can be obtained, and power consumption can be reduced. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 2⁄5 of the period of the input image data.

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

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

When the conversion ratio is 6, the moving picture quality can be improved more than when the conversion ratio is smaller than 6, and power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 6. Furthermore, since m is small, high image quality can be obtained, and power consumption can be reduced. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 1⁄6 of the cycle of the input image data.

When the conversion ratio is 6/5, the quality of moving pictures can be improved more than when the conversion ratio is smaller than 6/5, and power consumption and manufacturing cost can be reduced as compared with the case where the conversion ratio is larger than 6/5. Furthermore, since m is large, the motion of the image can be smoother. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 5/6 times the cycle of input image data.

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

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

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

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

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

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

When the conversion ratio is 8, the moving picture quality can be improved more than when the conversion ratio is smaller than 8, and power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 8. Furthermore, since m is small, high image quality can be obtained, and power consumption can be reduced. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 1⁄8 of the cycle of input image data.

When the conversion ratio is 8/3, the moving picture quality can be improved more than when the conversion ratio is smaller than 8/3, and power consumption and manufacturing cost can be reduced as compared with the conversion ratio larger than 8/3. Furthermore, since m is large, the motion of the image can be smoother. Furthermore, the image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 3⁄8 of the cycle of the input image data.

When the conversion ratio is 8/5, the quality of moving pictures can be improved more than when the conversion ratio is smaller than 8/5, and power consumption and manufacturing cost can be reduced as compared with the case where the conversion ratio is larger than 8/5. Furthermore, since m is large, the motion of the image can be smoother. Furthermore, the image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 5/8 times the cycle of the input image data.

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

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

When the conversion ratio is 9/2, the moving picture quality can be improved more than when the conversion ratio is smaller than 9/2, and power consumption and manufacturing cost can be reduced as compared with the conversion ratio larger than 9/2. Furthermore, since m is small, high image quality can be obtained, and power consumption can be reduced. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 2/9 times the period of the input image data.

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

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

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

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

When the conversion ratio is 10, the quality of the moving image can be improved compared to when the conversion ratio is less than 10,
Power consumption and manufacturing cost can be reduced more than when the conversion ratio is greater than 10. Furthermore, m
Is small, power consumption can be reduced while high image quality can be obtained. Furthermore, by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 1/10 of the cycle of the input image data,
Image quality can be improved.

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

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

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

It should be noted that it is apparent that each conversion ratio in the range where n is greater than 10 has similar advantages.

Next, as a second step, an image according to the input image data or each image frame rate converted to an arbitrary rational number (n / m) in the first step (referred to as an original image) A method of creating a plurality of different images (sub-images) and presenting the plurality of sub-images sequentially in time will be described. By doing this, although the user is actually presenting a plurality of images, it can also be perceived visually by the human eye as if one original image was displayed.

Here, among the sub-images created from one original image, the sub-image to be displayed first is referred to as a first sub-image. Here, it is assumed that the timing to display the first sub-image is the same as the timing to display the original image determined in the first step. on the other hand,
The sub-image displayed thereafter is referred to as a second sub-image. The timing for displaying the second sub-image can be determined arbitrarily regardless of the timing for displaying the original image determined in the first step. The image to be actually displayed is an image created from the original image by the method in the second step. Note that various images can be used as the original image for creating the sub image. Note that the number of sub-images is not limited to two, and may be larger than two. In the second step, the number of sub-images is denoted as J (J is an integer of 2 or more). At this time, a sub-image displayed at the same timing as the display timing of the original image determined in the first step is referred to as a first sub-image, and a sub-image subsequently displayed is displayed. Second sub-image, third sub-image,.
, And the Jth sub-image.

Although there are various methods for creating a plurality of sub-images from one original image, the following methods can be mentioned as main ones. One is a method of using the original image as it is as a sub-image. One is a method of distributing the brightness of the original image to a plurality of sub-images. One is a method of using an intermediate image obtained by motion compensation as a sub-image.

Here, the method of distributing the brightness of the original image to a plurality of sub-images can be further divided into a plurality of methods. The following can be mentioned as main ones. One is a method of making at least one sub-image a black image (referred to as a black insertion method). One is
When the brightness of the original image is divided into a plurality of ranges and the brightness in the range is controlled, a method of using only one sub image of all the sub images (referred to as a time division gradation control method) ). First, one sub-image is a bright image in which the gamma value of the original image is changed, and the other sub-image is a dark image in which the gamma value of the original image is changed ).

Each of the above mentioned methods will be briefly described. The method of using the original image as it is as the sub image uses the original image as it is as the first sub image. Furthermore, the original image is used as it is as the second sub-image. By using this method, power consumption and manufacturing cost can be reduced because a circuit for creating a sub-image is not operated or it is not necessary to use the circuit itself. In particular, in the liquid crystal display device, the first
It is preferable to use this method after performing frame rate conversion in which an intermediate image determined by motion compensation is an interpolated image in the step of. The reason is that, by making the intermediate image obtained by the motion compensation as the interpolation image, the same image is repeatedly displayed while smoothing the motion of the moving image, the moving image is caused by the shortage of the writing voltage due to the dynamic capacitance of the liquid crystal element. This is because it is possible to reduce obstacles such as tailing and afterimage.

Next, in the method of distributing the brightness of the original image to a plurality of sub-images, the method of setting the brightness of the image and the length of the period in which the sub-image is displayed will be described in detail. Here, J represents the number of sub-images and is an integer of 2 or more. Lower case j is distinguished from upper case J. It is assumed that j is an integer of 1 or more and J or less.
The brightness of the pixel in normal hold driving is L, and the period of the original image data is T,
The brightness L _j of the pixels in the sub-image of the _j, the length T _j of the period in which the sub image is displayed in the first _j, and when taking a product for L _j and T _j, from which the j = 1 Sum up to j = J (L
It is preferable that ₁ T ₁ + L ₂ T ₂ +... + L _J T _J ) be equal to the product of L and T (LT) (brightness does not change). Furthermore, the _{T j,} the sum of j = 1 through _{j = J (T 1 + T} 2 + ··· + T J) is that is equal to the T (the display period of the original image is maintained) of preferable. Here, that the brightness is unchanged and the display cycle of the original image is maintained is referred to as a sub-image distribution condition.

Among the methods of distributing the brightness of the original image to a plurality of sub-images, the black insertion method is a method of making at least one sub-image a black image. By doing this, the display method can be simulated in an impulse type, so that it is possible to prevent the deterioration of the quality of the moving image due to the display method being a hold type. Here, in order to prevent the decrease in brightness of the display image accompanying the insertion of the black image, it is preferable to follow the sub-image distribution conditions. However, in the case where the decrease in the brightness of the display image is acceptable (such as when the surroundings are dark), the sub-image is set if the user is set such that the decrease in the brightness of the display image is acceptable. It is not necessary to follow the distribution conditions. 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 condition is followed. Furthermore, in the liquid crystal display device, when it is assumed that one of the sub-images has the overall brightness of the original image increased without limiting the maximum value of the brightness, the brightness of the backlight should be increased. Sub-image distribution conditions may be realized. In this case, since the sub image distribution condition can be satisfied without controlling the voltage value written to the pixel, the operation of the image processing circuit can be omitted, and power consumption can be reduced.

The black insertion method is characterized in that L _{j of} all pixels is 0 in any one sub-image. By this means, since the display method can be simulated in an impulse type, it is possible to prevent the deterioration of the quality of the moving image due to the display method being a hold type.

Among the methods of distributing the brightness of the original image to a plurality of sub-images, the time division gradation control method divides the brightness of the original image into a plurality of ranges, and when controlling the brightness in the ranges, all The method is performed by only one sub-image among the sub-images of. By doing this, the display method can be pseudo-impulse-type without lowering the brightness, so that it is possible to prevent the deterioration of the quality of the moving image caused by the hold-type display method.

As a method of dividing the brightness of the original image into multiple ranges, the maximum value of brightness (L _max ),
There is a method of dividing by the number of sub-images. This is because, for example, in a display device in which the brightness from 0 to L _max can be adjusted in 256 steps (tone 0 to tone 255), when the number of sub-images is 2, tone 0 to tone 127 To display the brightness of one sub-image in the range of gradation 0 to gradation 255, while setting the brightness of the other sub-image to gradation 0,
When displaying from gray level 128 to gray level 255, the brightness of one sub image is gray level 255
On the other hand, the brightness of the other sub-image is adjusted in the range of gradation 0 to gradation 255. By doing this, the original image can be perceived by the human eye as if it were displayed, and since it can be pseudo-impulse-type, the quality of the moving image is degraded due to being of the hold-type. You can prevent. The number of sub-images may be larger than two. For example, if the number of sub-images is three, the brightness level of the original image (gradation 0 to gradation 2
55) is divided into three. Depending on the number of brightness levels of 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 it is included in the range of each brightness after division The number of stages of brightness may be distributed as appropriate, even if not exactly the same.

Also in the time-division gradation control method, it is preferable to satisfy the sub-image distribution condition, since the same image as the original image can be displayed without a decrease in brightness and the like.

Among the methods of distributing the brightness of the original image to a plurality of sub-images, the gamma complement method makes one sub-image a bright image with the gamma characteristics of the original image changed and the other sub-image the gamma of the original image. It is a method to make it a dark image whose characteristics are changed. By doing this, the display method can be pseudo-impulse-type without lowering the brightness, so that it is possible to prevent the deterioration of the quality of the moving image caused by the hold-type display method. Here, the gamma characteristic is the degree of brightness with respect to the brightness level (gradation). Usually, the gamma characteristic is adjusted to be close to linear. This is because if the change in brightness is proportional to the gray level, which is the level of brightness, a smooth gray level can be obtained. In the gamma complement method, the gamma characteristics of one sub-image are shifted from linear and adjusted to be brighter than linear in the middle brightness (halftone) region (halftone becomes an image brighter than the original) )
. Then, the gamma characteristics of the other sub-image are also deviated from linear, and adjusted so as to be darker than linear in the same half tone region (half tone becomes an image darker than originally). Here, the amount by which one sub-image is brighter than linear and the amount by which the other sub-image is darker than linear
It is preferable to make them approximately equal in all gradations. In this way, the original image can be perceived by the human eye as if it were displayed, and degradation of the quality of the moving image due to being of the hold type can be prevented. The number of sub-images may be larger than two. For example, if the number of sub-images is three, then the gamma characteristics are adjusted for each of the three sub-images so that the sum of the linear to brightening amount and the sum of the linear to darkening amount are approximately equal. Good.

Also in the gamma complement method, it is preferable to satisfy the sub-image distribution condition because the same image as the original image can be displayed without a decrease in brightness or the like. further,
In the gamma complement method, the change in the brightness L _j of each sub-image with respect to the gradation follows the gamma curve, so that each sub-image can display the gradation smoothly by itself.
It has the advantage of also improving the quality of the image perceived by the human eye in the end.

A method of using an intermediate image determined by motion compensation as a sub image is a method of setting one sub image as an intermediate image determined by motion compensation from preceding and succeeding images. By doing this, the motion of the image can be smoothed, so the quality of the moving image can be improved.

Next, the relationship between the timing of displaying the sub image and the method of creating the sub image will be described. The timing for displaying the first sub-image is the same as the timing for displaying the original image determined in the first step, and the timing for displaying the second sub-image is the source determined in the first step Although it can be determined arbitrarily regardless of the timing of displaying the image, the sub-image itself may be changed according to the timing of displaying the second sub-image. By doing this, even if the timing of displaying the second sub-image is variously changed, it can be perceived by the human eye as if the original image was displayed. Specifically, when the timing for displaying the second sub-image is advanced, the first sub-image is made brighter, and the second
Sub-images can be darker. Furthermore, if the timing to display the second sub-image is delayed, the first sub-image can be darker and the second sub-image can be brighter. This is because the brightness perceived by the human eye changes depending on the length of the period in which the image is displayed. More specifically, the brightness perceived by human eyes is brighter as the image display period is longer, and is darker as the image display period is shorter. That is, by shortening the timing of displaying the second sub image, the length of the period in which the first sub image is displayed is shortened, and the length of the period in which the second sub image is displayed is increased. As it is, the first sub-image is dark and the second sub-image is bright and perceived by human eyes. As a result, an image different from the original image will be perceived by the human eye.
The second sub-image can be made brighter and the second sub-image can be made darker. Similarly, the second
By delaying the timing of displaying the second sub-image, the length of the period of displaying the first sub-image becomes longer, and the length of the period of displaying the second sub-image becomes shorter. The sub-image may be darker and the second sub-image may be brighter.

Based on the above description, the processing procedure in the second step is shown below.
As procedure 1, a method of creating a plurality of sub-images from one original image is determined. More specifically, a method of creating a plurality of sub-images includes a method of using the original image as it is as a sub-image, a method of distributing the brightness of the original image to a plurality of sub-images, It can be selected from the methods used as
In step 2, the number J of sub-images is determined. Here, J is an integer of 2 or more.
In step 3, the brightness L _j of the pixel in the j-th sub-image and the length T _{j of the} period in which the j-th sub-image is displayed are determined according to the method selected in step 1. In procedure 3, the length of the period in 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 and actually displayed according to the items determined in each of steps 1 to 3.
In step 5, move the target original image to the next original image. Then, return 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 a mechanism for executing the procedure in the second step is implemented in the device, it is possible to switch the driving method so that the optimum operation according to the situation is performed. Note that the conditions mentioned here are the contents of the image data, the environment inside and outside the device (temperature, humidity, pressure, light, sound, magnetic field, electric field, radiation dose,
Includes altitude, acceleration, travel speed, etc., user settings, software versions, etc. On the other hand, if the mechanism for executing the procedure in the second step is determined in advance at the design stage of the apparatus, the drive circuit optimum for each drive method can be used, and the mechanism is determined. Thus, it is possible to expect a reduction in manufacturing cost due to mass production effects.

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

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

I-th (i is a positive integer) image data,
The (i + 1) th image data are sequentially prepared at a constant period T,
The period T is divided into J (J is an integer of 2 or more) sub image display periods,
The i-th image data is data that can make the plurality of pixels have unique brightness L, respectively.
The j-th (j is an integer of 1 or more and J or less) sub-image is configured by juxtaposing a plurality of pixels each having unique brightness L _j, and is displayed only during the j-th sub-image display period T _j It is an image,
A method of driving a display device satisfying a sub image distribution condition, wherein L, T, L _j and T _j satisfy the sub image distribution condition,
In all j, the brightness L _j of each pixel included in the j-th sub-image is characterized by L _j = L for each pixel.
Here, the original image data created in the first step can be used as the image data sequentially prepared in a fixed cycle T. That is, all the display patterns mentioned in the description of the first step can be combined with the above driving method.

Then, when the number J of sub-images is determined to be 2 in procedure 2 in the second step and T ₁ = T ₂ = T / 2 is determined in procedure 3, the above-mentioned driving method is shown in FIG. 71. It will be like.
In FIG. 71, the horizontal axis represents time, and the vertical axis represents the cases of the various n and m used in the first step.

For example, in the first step, when n = 1, m = 1, that is, when the conversion ratio (n / m) is 1, the driving method as shown at n = 1, m = 1 in FIG. Become. 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 (driven at 120 Hz). Then, an image is displayed twice continuously for one input image data. Here, in the case of double-speed driving, the quality of moving pictures can be improved more than in the case where the frame rate is smaller than double speed, and power consumption and manufacturing cost can be reduced as compared with the case where the frame rate is larger than double speed. Furthermore, in step 1 of the second step,
By selecting a method that uses the original image as it is as a sub-image, the operation of the circuit that creates the intermediate image can be stopped by motion compensation or the circuit itself can be omitted from the device, so power consumption and device manufacturing cost Can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, it is also effective to combine the AC drive and the 120 Hz drive of the liquid crystal display device. That is, while setting the drive frequency of the liquid crystal display device to 120 Hz, the frequency of AC drive is an integral multiple or an integer fraction of that (for example, 30 Hz, 60 Hz)
, 120 Hz, 240 Hz, etc.), it is possible to reduce flicker that appears due to AC drive to such an extent that it can not be perceived by human eyes. Furthermore, the image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately half of the cycle of the input image data.

Furthermore, for example, in the first step, n = 2, m = 1, ie, the conversion ratio (n / m)
When 2) is 2, the driving method is as shown at n = 2 and m = 1 in FIG. 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, an image is displayed four times consecutively for one input image data. At this time, when the interpolation image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. Here, in the case of quadruple speed drive, the quality of moving pictures can be improved more than in the case where the frame rate is smaller than quadruple speed, and power consumption and manufacturing cost can be reduced as compared with the case where the frame rate is larger than quadruple speed. Furthermore, in the procedure 1 of the second step, the method of using the original image as it is as a sub-image is selected to stop the operation of the circuit that creates the intermediate image by motion compensation or omit the circuit itself from the device. Power consumption and device manufacturing costs can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device,
Since the problem of write voltage shortage due to the dynamic capacitance can be avoided, the image quality improvement effect is particularly remarkable for failures such as tailing of moving images and afterimages. Furthermore, it is also effective to combine the AC drive and the 240 Hz drive of the 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 AC drive to an integral multiple or an integral fraction of it (for example, 30 Hz, 60 Hz, 120 Hz, 240 Hz, etc.) It can be reduced to an extent that is not perceived by human eyes. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 1⁄4 of the cycle of the input image data.

Furthermore, for example, in the first step, n = 3, m = 1, ie, the conversion ratio (n / m)
When d) is 3, the driving method is as shown at n = 3 and m = 1 in FIG. At this time, the display frame rate is six times the frame rate of the input image data (6-fold speed drive). Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 360 Hz (360 Hz drive). Then, an image is continuously displayed six times for one input image data. At this time, when the interpolation image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. Here, in the case of 6 × speed driving, the quality of moving pictures can be improved more than in the case where the frame rate is smaller than 6 × speed, and power consumption and manufacturing cost can be reduced as compared with the case of larger than 6 × speed. Furthermore, in the procedure 1 of the second step, the method of using the original image as it is as a sub-image is selected to stop the operation of the circuit that creates the intermediate image by motion compensation or omit the circuit itself from the device. Power consumption and device manufacturing costs can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device,
Since the problem of write voltage shortage due to the dynamic capacitance can be avoided, the image quality improvement effect is particularly remarkable for failures such as tailing of moving images and afterimages. Furthermore, it is also effective to combine the AC drive and the 360 Hz drive of the 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 AC drive to an integral multiple or an integral fraction of it (for example, 30 Hz, 60 Hz, 120 Hz, 180 Hz, etc.) It can be reduced to an extent that is not perceived by human eyes. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 1⁄6 of the cycle of the input image data.

Furthermore, for example, in the first step, n = 3, m = 2, ie, the conversion ratio (n / m)
When 3) is 3/2, the driving method is as shown at n = 3 and m = 2 in FIG.
At this time, the display frame rate is three times (three times faster) the frame rate of the input image data. Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 180 Hz (180 Hz drive). Then, an image is displayed three times consecutively for one input image data. At this time, when the interpolation image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. Where 3
In the case of double speed driving, the quality of moving pictures can be improved as compared with the case where the frame rate is smaller than triple speed, and power consumption and manufacturing cost can be reduced as compared with the case where the frame rate is larger than triple speed. Furthermore, in the procedure 1 of the second step, the method of using the original image as it is as a sub-image is selected to stop the operation of the circuit that creates the intermediate image by motion compensation or omit the circuit itself from the device. Power consumption and device manufacturing costs can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, it is also effective to combine the AC drive and the 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 AC drive to an integral multiple or an integral fraction of it (for example, 30 Hz, 60 Hz, 120 Hz, 180 Hz, etc.) It can be reduced to an extent that is not perceived by human eyes. Furthermore, the image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is about 1⁄3 of the cycle of the input image data.

Furthermore, for example, in the first step, n = 4, m = 1, ie, the conversion ratio (n / m)
When d) is 4, the driving method is as shown at n = 4 and m = 1 in FIG. At this time, the display frame rate is eight times (eight-fold speed drive) the frame rate of the input image data. Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 480 Hz (driven at 480 Hz). Then, an image is continuously displayed eight times for one input image data. At this time, when the interpolation image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. Here, in the case of 8 × speed driving, the quality of moving pictures can be improved more than in the case where the frame rate is smaller than 8 × speed, and the power consumption and the manufacturing cost can be reduced as compared with the case of larger 8 × speed. Furthermore, in the procedure 1 of the second step, the method of using the original image as it is as a sub-image is selected to stop the operation of the circuit that creates the intermediate image by motion compensation or omit the circuit itself from the device. Power consumption and device manufacturing costs can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device,
Since the problem of write voltage shortage due to the dynamic capacitance can be avoided, the image quality improvement effect is particularly remarkable for failures such as tailing of moving images and afterimages. Furthermore, it is also effective to combine the AC drive and 480 Hz drive of the liquid crystal display device. That is, by setting the drive frequency of the liquid crystal display device to 480 Hz and setting the frequency of the AC drive to an integral multiple or an integer fraction (for example, 30 Hz, 60 Hz, 120 Hz, 240 Hz, etc.) It can be reduced to an extent that is not perceived by human eyes. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 1⁄8 of the cycle of input image data.

Furthermore, for example, in the first step, n = 4, m = 3, ie, the conversion ratio (n / m)
When 4) is 4/3, the driving method is as shown at n = 4 and m = 3 in FIG.
At this time, the display frame rate is 8/3 times the frame rate of the input image data (8
/ 3x speed drive). Specifically, for example, when the input frame rate is 60 Hz, the display frame rate is 160 Hz (160 Hz drive). Then, images are continuously displayed eight times for three input image data. At this time, when the interpolation image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. Here, in the case of 8 / 3-speed driving, the quality of moving pictures can be improved more than in the case where the frame rate is smaller than 8 / 3-speed, and power consumption and manufacturing cost can be reduced as compared with those larger than 8 / 3-speed. Furthermore, in the procedure 1 of the second step, the method of using the original image as it is as a sub-image is selected to stop the operation of the circuit that creates the intermediate image by motion compensation or omit the circuit itself from the device. Power consumption and device manufacturing costs can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage.
Furthermore, it is also effective to combine the AC drive and the 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 setting the frequency of AC drive to an integral multiple or an integral fraction (for example, 40 Hz, 80 Hz, 160 Hz, 320 Hz, etc.) It can be reduced to an extent that is not perceived by human eyes. Furthermore, the image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 3⁄8 of the cycle of the input image data.

Furthermore, for example, in the first step, n = 5, m = 1, ie, the conversion ratio (n / m
When the value of 5) is 5, the driving method is as shown at n = 5 and m = 1 in FIG. At this time, the display frame rate is 10 times (10 × speed drive) the frame rate of the input image data. Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 600 Hz (600 Hz drive). Then, an image is continuously displayed ten times for one input image data. At this time, when the interpolation image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. here,
In the case of 10-fold speed drive, the quality of moving pictures can be improved more than in the case where the frame rate is smaller than 10-fold speed, and power consumption and manufacturing cost can be reduced as compared with those larger than 10-fold speed. Furthermore, in the procedure 1 of the second step, the method of using the original image as it is as a sub-image is selected to stop the operation of the circuit that creates the intermediate image by motion compensation or omit the circuit itself from the device. Power consumption and device manufacturing costs can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, it is also effective to combine the AC drive and the 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 AC drive to an integral multiple or an integral fraction (for example, 30 Hz, 60 Hz, 100 Hz, 120 Hz, etc.) It can be reduced to an extent that is not perceived by human eyes. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 1/10 of the cycle of input image data.

Furthermore, for example, in the first step, n = 5, m = 2, ie, the conversion ratio (n / m
When 5) is 5/2, the driving method is as shown at n = 5 and m = 2 in FIG.
At this time, the display frame rate is five times the frame rate of the input image data (five-fold speed drive). Specifically, for example, if the input frame rate is 60 Hz, the display frame rate is 300 Hz (300 Hz drive). Then, an image is continuously displayed five times for one input image data. At this time, when the interpolation image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. Here, in the case of 5 × speed driving, the quality of moving pictures can be improved more than in the case where the frame rate is smaller than 5 × speed, and power consumption and manufacturing cost can be reduced as compared with the case of larger than 5 × speed. Furthermore, the second
In step 1 of the above step, the method of using the original image as a sub-image as it is is selected, so that the operation of the circuit for creating the intermediate image can be stopped by motion compensation or the circuit itself can be omitted from the device. Power consumption and device manufacturing costs can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, it is also effective to combine the AC drive and the 300 Hz drive of the liquid crystal display device. That is, while setting the driving frequency of the liquid crystal display device to 300 Hz, the frequency of alternating current driving is an integral multiple or an integer fraction
For example, by setting the frequency to 30 Hz, 50 Hz, 60 Hz, 100 Hz, etc.), it is possible to reduce flicker that appears due to AC drive to such an extent that human eyes do not perceive it. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately 1⁄5 of the period of the input image data.

Thus, in procedure 1 in the second step, the method of using the original image as it is as the sub image is selected,
In procedure 2 in the second step, the number of sub-images is determined to be 2,
If it is determined in step 3 in the second step that T1 = T2 = T / 2, then the first
Since the display frame rate can be further doubled with respect to the frame rate conversion of the conversion ratio determined by the values of n and m in the above step, the quality of moving pictures can be further improved. Furthermore, the quality of moving pictures can be improved as compared to the case where the display frame rate is smaller than the display frame rate, and power consumption and manufacturing cost can be reduced as compared to the case where the display frame rate is larger than the display frame rate.
Furthermore, in the procedure 1 of the second step, the method of using the original image as it is as a sub-image is selected to stop the operation of the circuit that creates the intermediate image by motion compensation or omit the circuit itself from the device. Power consumption and device manufacturing costs can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. further,
By increasing the drive frequency of the liquid crystal display device and setting the frequency of AC drive to an integral multiple or an integral fraction of that frequency, it is possible to reduce flicker that appears due to AC drive to such an extent that human eyes do not perceive it. Furthermore, the response time of the liquid crystal element of the period of the input image data
The image quality can be improved by applying to a liquid crystal display device which is approximately 1 / (twice of a conversion ratio)).

Although the detailed description has been omitted, it is apparent that similar advantages can be obtained in cases other than the conversion ratios mentioned above. For example, in the range where n is 10 or less, in addition to those listed above,
n = 5, m = 3, that is, conversion ratio (n / m) = 5/3 (10/3 speed drive, 200 Hz)
,
n = 5, m = 4, that is, conversion ratio (n / m) = 5/4 (5 / 2-speed drive, 150 Hz),
n = 6, m = 1, that is, conversion ratio (n / m) = 6 (12 × drive, 720 Hz),
n = 6, m = 5, that is, conversion ratio (n / m) = 6/5 (12/5 double speed drive, 144 Hz)
,
n = 7, m = 1, that is, conversion ratio (n / m) = 7 (14 × drive, 840 Hz),
n = 7, m = 2, that is, conversion ratio (n / m) = 7/2 (7 × speed drive, 420 Hz),
n = 7, m = 3, that is, conversion ratio (n / m) = 7/3 (14/3 double speed drive, 280 Hz)
,
n = 7, m = 4, that is, conversion ratio (n / m) = 7/4 (7 / 2-speed drive, 210 Hz),
n = 7, m = 5, that is, conversion ratio (n / m) = 7/5 (14/5 double speed drive, 168 Hz)
,
n = 7, m = 6, that is, conversion ratio (n / m) = 7/6 (7/3 speed drive, 140 Hz),
n = 8, m = 1, that is, conversion ratio (n / m) = 8 (16 × driving, 960 Hz),
n = 8, m = 3, that is, conversion ratio (n / m) = 8/3 (16/3 speed drive, 320 Hz)
,
n = 8, m = 5, that is, conversion ratio (n / m) = 8/5 (16/5 speed drive, 192 Hz)
,
n = 8, m = 7, that is, conversion ratio (n / m) = 8/7 (16/7 double speed drive, 137 Hz)
,
n = 9, m = 1, that is, conversion ratio (n / m) = 9 (18 × drive, 1080 Hz),
n = 9, m = 2, that is, conversion ratio (n / m) = 9/2 (9 × driving, 540 Hz),
n = 9, m = 4, that is, conversion ratio (n / m) = 9/4 (9 / 2-speed drive, 270 Hz),
n = 9, m = 5, that is, conversion ratio (n / m) = 9/5 (18/5 speed drive, 216 Hz)
,
n = 9, m = 7, that is, conversion ratio (n / m) = 9/7 (18/7 double speed drive, 154 Hz)
,
n = 9, m = 8, that is, conversion ratio (n / m) = 9/8 (9/4 speed drive, 135 Hz),
n = 10, m = 1, that is, conversion ratio (n / m) = 10 (20 × drive, 1200 Hz),
n = 10, m = 3, that is, conversion ratio (n / m) = 10/3 (20 / 3-speed driving, 400 H
z),
n = 10, m = 7, that is, conversion ratio (n / m) = 10/7 (20/7 double speed drive, 171 H
z),
n = 10, m = 9, that is, conversion ratio (n / m) = 10/9 (20/9 double speed drive, 133 H
z),
Combinations of the above are conceivable. The notation of frequency is an example when the input frame rate is 60 Hz, and for the other input frame rates, a value obtained by integrating two times each conversion ratio with the input frame rate is the driving frequency.

In the case where n is an integer greater than 10, it is obvious that the procedure in the second step can be applied to various n and m, although specific numbers of n and m are not listed. .

When J = 2, it is particularly effective if the conversion ratio in the first step is larger than 2. This is because, in the second step, if the number of sub-images is relatively reduced to J = 2, the conversion ratio in the first step can be increased accordingly. Such conversion ratios are 3, 4, 5, 5/2, 6, 7 in the range where n is 10 or less.
, 7/2, 7/3, 8, 8/3, 9, 9/2, 9/4, 10, 10/3, and the like.
When the display frame rate after the first step is such a value, the advantage of reducing the number of sub-images in the second step by setting J = 3 or more (such as reduction of power consumption and manufacturing cost) In addition, it is possible to make the advantages of the large final display frame rate (improvement of moving picture quality, reduction of flicker, etc.) compatible with each other.

Here, in step 2, the number J of sub-images is determined to be 2, and in step 3, T ₁ =
Although the case where it is determined that T ₂ = T / 2 has been described, it is apparent 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 , it is possible to make the first sub-image brighter and the second sub-image darker. Furthermore, the second
If it is determined in step 3 that T ₁ > T ₂ , the first sub-image can be darker and the second sub-image can be brighter. In this way, the original image can be perceived properly by the human eye, and the display can be artificially driven by impulse, so that the quality of the moving image can be improved. However, when the method of using the original image as it is as the sub image is selected in the procedure 1 as in the above-described driving method, the brightness of the sub image may be displayed as it is without changing. This is because, in this case, since the image used as the sub image is the same, the original image can be properly displayed regardless of the display timing of the sub image.

Furthermore, it is obvious that in the procedure 2, the number J of sub-images may be determined not to 2 but to any other value. In this case, as compared with the frame rate conversion of the conversion ratio determined by the values of n and m in the first step, the display frame rate can be further increased to a J-fold frame rate, thereby further improving the moving picture quality. Is possible. Furthermore, the quality of moving pictures can be improved as compared to the case where the display frame rate is smaller than the display frame rate, and power consumption and manufacturing cost can be reduced as compared to the case where the display frame rate is larger than the display frame rate. Furthermore, in the procedure 1 of the second step, the method of using the original image as it is as a sub-image is selected to stop the operation of the circuit that creates the intermediate image by motion compensation or omit the circuit itself from the device. Power consumption and device manufacturing costs can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, by increasing the drive frequency of the liquid crystal display device and setting the frequency of AC drive to an integral multiple or integral fraction thereof, the flicker appearing by the AC drive can be reduced to such an extent that it can not be perceived by human eyes. it can. Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately (1 / (J times the conversion ratio)) of the cycle of the input image data.

For example, when J = 3, the quality of moving pictures can be improved more than when the number of sub-images is less than 3, and power consumption and manufacturing cost can be reduced more than when the number of sub-images is greater than 3 Have an advantage. Furthermore, the response time of the liquid crystal element of the input image data period (1
The image quality can be improved by applying to a liquid crystal display device which is approximately / (3 times the conversion ratio)).

Furthermore, for example, when J = 4, the quality of moving pictures can be improved more than when the number of sub-images is smaller than 4, and the power consumption and manufacturing cost can be reduced more than when the number of sub-images is larger than 4 It has the advantage of being able to Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately (1 / (4 times the conversion ratio)) of the cycle of the input image data.

Furthermore, for example, when J = 5, the quality of moving pictures can be improved more than when the number of sub-images is less than 5, and power consumption and manufacturing cost can be reduced more than when the number of sub-images is greater than 5 It has the advantage of being able to Furthermore, image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately (1 / (5 times the conversion ratio)) of the cycle of input image data.

Furthermore, even if J is other than those listed above, it has similar advantages.

When J = 3 or more, the conversion ratio in the first step can take various values, but in particular, when the conversion ratio in the first step is relatively small (2 or less), J = 3
It is effective to set it as above. This is because if the display frame rate after the first step is relatively small, J can be increased in the second step accordingly. Such conversion ratios are 1, 2, 3/2, 4/3, and so on in the range where n is 10 or less.
5/3, 5/4, 6/5, 7/4, 7/5, 7/6, 8/7, 9/5, 9/7, 9/8,
10/7 and 10/9. Among them, the conversion ratio is 1, 2, 3/2, 4/3, 5 /
The cases of 3 and 5/4 are illustrated in FIG. As described above, when the display frame rate after the first step is a relatively small value, the advantage of the small display frame rate in the first step can be obtained by setting J to 3 or more (power consumption and manufacturing cost). It is possible to simultaneously achieve the advantages (reduction of moving image, reduction of flicker, etc.) due to the reduction of the display frame rate and the large final display frame rate.

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 among the methods of distributing the brightness of the original image to a plurality of sub-images, the driving method is as follows.

I-th (i is a positive integer) image data,
The (i + 1) th image data are sequentially prepared at a constant period T,
The period T is divided into J (J is an integer of 2 or more) sub image display periods,
The i-th image data is data that can make the plurality of pixels have unique brightness L, respectively.
The j-th (j is an integer of 1 or more and J or less) sub-image is configured by juxtaposing a plurality of pixels each having unique brightness L _j, and is displayed only during the j-th sub-image display period T _j It is an image,
A method of driving a display device satisfying a sub image distribution condition, wherein L, T, L _j and T _j satisfy the sub image distribution condition,
In at least one j, the brightness L _{j of} all the pixels contained in the j-th sub-image is L _j
It is characterized in that = 0.
Here, the original image data created in the first step can be used as the image data sequentially prepared in a fixed cycle T. That is, all the display patterns mentioned in the description of the first step can be combined with the above driving method.

It is apparent that the above driving method can be implemented in combination for each of the various n and m used in the first step.

Then, when the number J of sub-images is determined to be 2 in procedure 2 in the second step and T ₁ = T ₂ = T / 2 is determined in procedure 3, the above-mentioned driving method is shown in FIG. 71. It will be like.
The features and advantages of the driving method (display timing at various n and m) shown in FIG. 71 have already been described, so detailed description is omitted here, but in step 1 in the second step, the brightness of the original image It is apparent that the same method is obtained even when the black insertion method is selected among the methods of distributing the image into a plurality of sub-images. For example, in the case where the interpolation image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. Furthermore, when the display frame rate is large, the quality of moving pictures can be improved, and when the display frame rate is small, power consumption and manufacturing cost can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, it is possible to reduce flicker that appears due to AC drive to an extent that is not perceived by the human eye

Among the methods of distributing the brightness of the original image to a plurality of sub-images in procedure 1 of the second step, a characteristic advantage of the black insertion method being selected is that an intermediate image is created by motion compensation. The operation of the circuit can be stopped or the circuit itself can be omitted from the device.
Power consumption and device manufacturing costs can be reduced. Further, since the display method of the impulse type can be simulated in a pseudo manner regardless of the gradation value included in the image data, the quality of the moving image can be improved.

Here, in step 2, the number J of sub-images is determined to be 2, and in step 3, T ₁ =
Although the case where it is determined that T ₂ = T / 2 has been described, it is apparent 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 , it is possible to make the first sub-image brighter and the second sub-image darker. Furthermore, the second
If it is determined in step 3 that T ₁ > T ₂ , the first sub-image can be darker and the second sub-image can be brighter. In this way, the original image can be perceived properly by the human eye, and the display can be artificially driven by impulse, so that the quality of the moving image can be improved. However, as in the driving method described above, when the black insertion method is selected among the methods of distributing the brightness of the original image to a plurality of sub-images in step 1, the brightness of the sub-image is not changed It may be displayed as it is. because,
In this case, when the brightness of the sub-image is not changed, the entire brightness of the original image is only displayed dark. That is, by actively using this method for controlling the brightness of the display device, it is possible to control the brightness while improving the quality of the moving image.

Furthermore, it is obvious that in the procedure 2, the number J of sub-images may be determined not to 2 but to any other value. Since the advantage in that case has already been described, the detailed description is omitted here, but in the procedure 1 in the second step, the black insertion method is one of the methods of distributing the brightness of the original image to a plurality of sub-images. It is clear that the selected advantages have similar advantages. For example, the response time of the liquid crystal element is 1 / (J times the conversion ratio) of the cycle of the input image data
The image quality can be improved by applying to a liquid crystal display device which is about double.

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 time division gradation control method is selected among the methods of distributing the brightness of the original image to a plurality of sub images, the driving method is as follows.

I-th (i is a positive integer) image data,
The (i + 1) th image data are sequentially prepared at a constant period T,
The period T is divided into J (J is an integer of 2 or more) sub image display periods,
The i-th image data is data that can make the plurality of pixels have unique brightness L, respectively.
The specific brightness L has a maximum value of L _max ,
The j-th (j is an integer of 1 or more and J or less) sub-image is configured by juxtaposing a plurality of pixels each having unique brightness L _j, and is displayed only during the j-th sub-image display period T _j It is an image,
A method of driving a display device satisfying a sub image distribution condition, wherein L, T, L _j and T _j satisfy the sub image distribution condition,
In order to display the unique brightness L, (j-1) × L _max / J to J × L _max
The adjustment of the brightness in the range of the brightness of / J is performed by the adjustment of 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 in a fixed cycle T. That is, all the display patterns mentioned in the description of the first step can be combined with the above driving method.

It is apparent that the above driving method can be implemented in combination for each of the various n and m used in the first step.

Then, when the number J of sub-images is determined to be 2 in procedure 2 in the second step and T ₁ = T ₂ = T / 2 is determined in procedure 3, the above-mentioned driving method is shown in FIG. 71. It will be like.
The features and advantages of the driving method (display timing at various n and m) shown in FIG. 71 have already been described, so detailed description is omitted here, but in step 1 in the second step, the brightness of the original image It is apparent that the same advantages can be obtained even in the case where the time division tone control method is selected among the methods of distributing H.sub.2 to a plurality of sub-images. For example, in the case where the interpolation image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. Furthermore, when the display frame rate is large, the quality of moving pictures can be improved, and when the display frame rate is small, power consumption and manufacturing cost can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, it is possible to reduce flicker that appears due to AC drive to an extent that is not perceived by 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, a characteristic advantage of selecting the time-division gradation control method is that an intermediate image is obtained by motion compensation. It is possible to reduce the power consumption and the manufacturing cost of the device, since the operation of the circuit that creates the can be stopped or the circuit itself can be omitted from the device. further,
Since the display method of the impulse type can be simulated, the quality of the moving image can be improved, and the brightness of the display device does not decrease, thereby further reducing power consumption.

Here, in step 2, the number J of sub-images is determined to be 2, and in step 3, T ₁ =
Although the case where it is determined that T ₂ = T / 2 has been described, it is apparent 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 , it is possible to make the first sub-image brighter and the second sub-image darker. Furthermore, the second
If it is determined in step 3 that T ₁ > T ₂ , the first sub-image can be darker and the second sub-image can be brighter. In this way, the original image can be perceived properly by the human eye, and the display can be artificially driven by impulse, so that the quality of the moving image can be improved. In this way, the original image can be perceived properly by the human eye, and the display can be artificially driven by impulse, so that the quality of the moving image can be improved.

Furthermore, it is obvious that in the procedure 2, the number J of sub-images may be determined not to 2 but to any other value. Since the advantage in that case has already been described, detailed explanation will be omitted here, but in the procedure 1 in the second step, time-division gradation among the methods of distributing the brightness of the original image to a plurality of sub-images It is clear that the same advantages are obtained when the control method is chosen. For example, the image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately (1 / (J times the conversion ratio)) of the cycle of the input image data.

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

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

I-th (i is a positive integer) image data,
The (i + 1) th image data are sequentially prepared at a constant period T,
The period T is divided into J (J is an integer of 2 or more) sub image display periods,
The i-th image data is data that can make the plurality of pixels have unique brightness L, respectively.
The j-th (j is an integer of 1 or more and J or less) sub-image is configured by juxtaposing a plurality of pixels each having unique brightness L _j, and is displayed only during the j-th sub-image display period T _j It is an image,
A method of driving a display device satisfying a sub image distribution condition, wherein L, T, L _j and T _j satisfy the sub image distribution condition,
In each sub-image, the characteristic of the change in brightness with respect to gradation is shifted from linear, and the sum of the amount of brightness shifted from linear to bright and the sum of the amount of brightness shifted from linear to dark , Substantially equal in all gradations.
Here, the original image data created in the first step can be used as the image data sequentially prepared in a fixed cycle T. That is, all the display patterns mentioned in the description of the first step can be combined with the above driving method.

It is apparent that the above driving method can be implemented in combination for each of the various n and m used in the first step.

Then, when the number J of sub-images is determined to be 2 in procedure 2 in the second step and T ₁ = T ₂ = T / 2 is determined in procedure 3, the above-mentioned driving method is shown in FIG. 71. It will be like.
The features and advantages of the driving method (display timing at various n and m) shown in FIG. 71 have already been described, so detailed description is omitted here, but in step 1 in the second step, the brightness of the original image It is apparent that among the methods of distributing H.sub.i.sup.2 to a plurality of sub-images, similar advantages are obtained even when the gamma complementation method is selected. For example, in the case where the interpolation image in the first step is an intermediate image obtained by motion compensation, the motion of the moving image can be smoothed, so that the quality of the moving image can be significantly improved. Furthermore, when the display frame rate is large, the quality of moving pictures can be improved, and when the display frame rate is small, power consumption and manufacturing cost can be reduced. Furthermore, when the display device is an active matrix liquid crystal display device, the problem of the shortage of the write voltage due to the dynamic capacitance can be avoided, so that the image quality improvement effect is particularly remarkable with respect to a failure such as tailing of a moving image or an afterimage. Furthermore, it is possible to reduce flicker that appears due to AC drive to an extent that is not perceived by 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, a characteristic advantage of the gamma complementation method being selected is that an intermediate image is created by motion compensation. Power consumption and manufacturing costs of the device can be reduced because the operation of the circuit can be stopped or the circuit itself can be omitted from the device. Further, since the display method of the impulse type can be simulated in a pseudo manner regardless of the gradation value included in the image data, the quality of the moving image can be improved. Further, the sub-image may be obtained by direct gamma conversion of the image data. In this case, there is an advantage that the gamma value can be controlled variously depending on the size of the motion of the moving image and the like. Furthermore, the image data may not be directly gamma converted, and a sub-image in which the gamma value is changed may be obtained by changing the reference voltage of the digital analog conversion circuit (DAC). In this case, since the image data is not directly gamma converted, the circuit that performs gamma conversion can be stopped or the circuit itself can be omitted from the device, so power consumption and device manufacturing cost can be reduced. . Furthermore, in the gamma complement method, the change in the brightness L _j of each sub-image with respect to the gradation follows the gamma curve, so that each sub-image can display the gradation smoothly on its own, and finally the human being It has the advantage of also improving the quality of the image perceived by the human eye.

Here, in step 2, the number J of sub-images is determined to be 2, and in step 3, T ₁ =
Although the case where it is determined that T ₂ = T / 2 has been described, it is apparent 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 , it is possible to make the first sub-image brighter and the second sub-image darker. Furthermore, the second
If it is determined in step 3 that T ₁ > T ₂ , the first sub-image can be darker and the second sub-image can be brighter. In this way, the original image can be perceived properly by the human eye, and the display can be artificially driven by impulse, so that the quality of the moving image can be improved. As in the above driving method, the procedure 1
In the method of distributing the brightness of the original image to a plurality of sub-images, if the gamma method is selected, the gamma value may be changed when the brightness of the sub-image is changed. 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, so power consumption and device manufacturing cost can be reduced.

Furthermore, it is obvious that in the procedure 2, the number J of sub-images may be determined not to 2 but to any other value. Since the advantage in that case has already been described, detailed explanation will be omitted here, but in the procedure 1 in the second step, time-division gradation among the methods of distributing the brightness of the original image to a plurality of sub-images It is clear that the same advantages are obtained when the control method is chosen. For example, the image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately (1 / (J times the conversion ratio)) of the cycle 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 procedure 1 in the second step, a method is selected in which an intermediate image obtained by motion compensation is used as a sub image,
In procedure 2 in the second step, the number of sub-images is determined to be 2,
When it is determined in step 3 in the second step that T1 = T2 = T / 2, the second
The driving method determined by the procedure in the step is as follows.

I-th (i is a positive integer) image data,
The (i + 1) th image data are sequentially prepared at a constant period T,
The kth (k is a positive integer) image,
The kth +1 image,
A method of driving a display device, which sequentially displays the (k + 2) th image at an interval of 1/2 times the period of the original image data,
The k-th image is displayed according to the i-th image data,
The (k + 1) -th image is displayed according to image data corresponding to a motion obtained by halving the motion from the i-th image data to the (i + 1) -th image data.
The (k + 2) -th image is displayed according to the (i + 1) -th image data.
Here, the original image data created in the first step can be used as the image data sequentially prepared in a fixed cycle T. That is, all the display patterns mentioned in the description of the first step can be combined with the above driving method.

It is apparent that the above driving method can be implemented in combination for each of the various n and m used in the first step.

A characteristic advantage of the method of using an intermediate image determined by motion compensation as a sub-image in procedure 1 in the second step is that the intermediate image determined by motion compensation in the procedure of the first step is When making it an interpolation image, the method of calculating | requiring the intermediate image used in the 1st step is a point which can be used by the 2nd step as it is. That is, since the circuit for obtaining an intermediate image by motion compensation can be used not only in the first step but also in the second step, the circuit can be effectively used and processing efficiency can be improved. In addition, since the motion of the image can be further smoothed, the quality of the moving image can be further improved.

Here, in step 2, the number J of sub-images is determined to be 2, and in step 3, T ₁ =
Although the case where it is determined that T ₂ = T / 2 has been described, it is apparent 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 , it is possible to make the first sub-image brighter and the second sub-image darker. Furthermore, the second
If it is determined in step 3 that T ₁ > T ₂ , the first sub-image can be darker and the second sub-image can be brighter. In this way, the original image can be perceived properly by the human eye, and the display can be artificially driven by impulse, so that the quality of the moving image can be improved. In this way, the original image can be perceived properly by the human eye, and the display can be artificially driven by impulse, so that the quality of the moving image can be improved. As in the above drive method, in step 2,
When a method of using an intermediate image determined by motion compensation as a sub image is selected, the brightness of the sub image may not be changed. This is because, since the image in the intermediate state is completed as an image by itself, even if the display timing of the second sub-image changes, it does not change as an image perceived by human eyes. In this case, the circuit for changing the brightness of the entire image 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, it is obvious that in the procedure 2, the number J of sub-images may be determined not to 2 but to any other value. Since the advantage in that case has already been described, the detailed description is omitted here, but the same applies to the case where the method of using the intermediate image obtained by motion compensation as the sub image is selected in procedure 1 in the second step. It is obvious to have the following advantages. For example, the image quality can be improved by applying to a liquid crystal display device in which the response time of the liquid crystal element is approximately (1 / (J times the conversion ratio)) of the cycle of the input image data.

Next, with reference to FIG. 73, a specific example of the frame rate conversion method in the case where the input frame rate and the display frame rate are different will be described. In the method shown in FIGS. 73A to 73C, it is assumed that the circular area on the image is an area where the position changes according to the frame, and the triangular area on the image is an area where the position hardly changes according to the frame. There is. However,
This is an example for explanation, and the displayed image is not limited to this. The methods of FIGS. 73 (A) to (C) can be applied to various images.

FIG. 73A shows the case where the display frame rate is twice the input frame rate (the conversion ratio is 2). When the conversion ratio is 2, it has the advantage that the quality of moving pictures can be improved more than when the conversion ratio is smaller than 2. Furthermore, when the conversion ratio is 2, it has the advantage that power consumption and manufacturing cost can be reduced more than when the conversion ratio is larger than 2. Figure 73 (
A) schematically represents the state of temporal change of the displayed image, with the horizontal axis as time. Here, the image of interest is described as a p-th image (p is a positive integer). Then, an image to be displayed next to the image of interest is a (p + 1) th image,
For convenience, it is described how far away from the image of interest the image displayed before the image of interest is displayed, such as the (p-1) image. To be. The image 7301 is the p-th image, the image 7302 is the (p + 1) -th image, the image 730
3 is the (p + 2) th image, the image 7304 is the (p + 3) th image, and the image 7305 is the (p +) image.
Suppose that it is the image of 4). The period Tin represents the period of input image data. Since FIG. 73A shows the case where the conversion ratio is 2, the period Tin is twice as long as the period from the display of the p-th image to the display of the (p + 1) -th image. It will be the length.

Here, the (p + 1) th image 7302 is the pth image 7301 to the (p + 2) th image 7
It may be an image created so as to be in an intermediate state between the p-th image 7301 and the (p + 2) -th image 7303 by detecting the amount of change in the images up to 303. In FIG. 73 (A), the state of the image in the intermediate state is represented by the area where the position changes according to the frame (circular area) and the area where the position does not substantially change according to the frame (triangular area). That is, the position of the circular area in the (p + 1) th image 7302 is the position of the pth image 7301.
And the position in the (p + 2) -th image 7303. That is, the (p + 1) th image 7302 is obtained by performing motion compensation and interpolating image data. As described above, by performing motion compensation on an object moving on an image and interpolating image data, smooth display can be performed.

Furthermore, the (p + 1) th image 7302 is an image in which the luminance of the image is controlled according to a certain rule after being generated so as to be in the intermediate state between the pth image 7301 and the (p + 2) th image 7303. May be The certain rule is, for example, the p-th image 73 as shown in FIG. 73 (A).
When a representative luminance of 01 is L and a representative luminance of the (p + 1) th image 7302 is Lc, L and Lc may have a relationship of L> Lc. Desirably, 0.1L <Lc <0.
There may be a relationship of 8L. More desirably, there may be a relation of 0.2L <Lc <0.5L. Or, conversely, there may be a relationship of L <Lc between L and Lc. Desirably, there may be a relation of 0.1Lc <L <0.8Lc. More preferably, 0
. There may be a relationship of 2Lc <L <0.5Lc. By doing so, since the display can be simulated in an impulse type, it is possible to suppress the afterimage of the eye.

The representative luminance of the image will be described in detail later with reference to FIG.

Thus, two different causes for motion blur (the motion of the image is not smooth,
By solving the image and the afterimage of the eye at the same time, it is possible to significantly reduce the motion blur.

Furthermore, the (p + 3) th image 7304 may also be created from the (p + 2) th image 7303 and the (p + 4) th image 7305 using a similar method. That is, the
The +3) image 7304 is the (p + 2) th image 7303 to the (p + 4) th image 7305.
The (p + 2) th image 7303 and the (p + 4) th image are detected by detecting the amount of image change up to
The image 7305 may be an image created so as to be in the intermediate state of the image 7305 and in which the brightness of the image is controlled according to a certain rule.

FIG. 73B shows a case where the display frame rate is three times the input frame rate (the conversion ratio is 3). FIG. 73 (B) schematically shows how an image displayed is temporally changed, with the horizontal axis representing time. The image 7311 is a p-th image, the image 7312 is a (p + 1) th image, the image 7313 is a (p + 2) th image, the image 7314 is a (p + 3) th image, the image 7315 is a (p + 4) th image, the image 7316 Is the (p + 5) image, image 7
It is assumed that 317 is the (p + 6) th image. The period Tin represents the period of input image data. Since FIG. 73 (B) shows the case where the conversion ratio is 3, the period Tin is
It is three times as long as the period until the (p + 1) th image is displayed after the pth image is displayed.

Here, the (p + 1) -th image 7312 and the (p + 2) -th image 7313 are detected by detecting the amount of change in the images from the p-th image 7311 to the (p + 3) -th image 7314. And the (p + 3) th image 7314 may be an intermediate state image. In FIG. 73 (B), the state of the image in the intermediate state is represented by the area where the position changes according to the frame (circular area) and the area where the position does not substantially change according to the frame (triangular area). That is, the (p + 1) th image 7312 and the
The position of the circular area in the image 7313 of 2) is the position in the p-th image 7311,
The middle position of the position in the (p + 3) th image 7314 is set. Specifically, when the moving amount of the circular area detected from the p-th image 7311 and the (p + 3) -th image 7314 is X, the position of the circular area in the (p + 1) -th image 7312 is It may be a position displaced about (1/3) X from the position in the p-th image 7311. Furthermore, the position of the circular area in the (p + 2) -th image 7313 may be a position displaced about (2/3) × from the position in the p-th image 7311. That is, the (p + 1) th image 7
The 312th and (p + 2) th images 7313 are obtained by performing motion compensation and interpolating image data. As described above, by performing motion compensation on an object moving on an image and interpolating image data, smooth display can be performed.

Furthermore, the (p + 1) th image 7312 and the (p + 2) th image 7313 are created so as to be in an intermediate state between the pth image 7311 and the (p + 3) th image 7314, and the brightness of the image is constant. It may be an image controlled by the rule of. The certain rule is, for example, FIG.
As in 3 (B), the representative luminance of the p-th image 7311 is L, the (p + 1) -th image 731
Assuming that the representative luminance of 2 is Lc1 and the representative luminance of the (p + 2) th image 7313 is Lc2, L> Lc1 or L> Lc2 or Lc1 = Lc2 in L, Lc1 and Lc2.
There may be a relationship. Desirably, there may be a relation of 0.1L <Lc1 = Lc2 <0.8L. More desirably, there may be a relationship of 0.2L <Lc = Lc2 <0.5L. Or, conversely, in L, Lc1, Lc2, L <Lc1 or L <Lc2
Alternatively, there may be a relationship of Lc1 = Lc2. Desirably, 0.1 Lc1 = 0.1 L
There may be a relationship of c2 <L <0.8 Lc1 = 0.8 Lc2. More preferably,
There may be a relationship of 0.2Lc1 = 0.2Lc2 <L <0.5Lc1 = 0.5Lc2. By doing so, since the display can be simulated in an impulse type, it is possible to suppress the afterimage of the eye. Alternatively, images in which the brightness is changed may be alternately displayed. By doing this, it is possible to shorten the cycle in which the luminance changes, so it is possible to reduce flicker.

Thus, two different causes for motion blur (the motion of the image is not smooth,
By solving the image and the afterimage of the eye at the same time, it is possible to significantly reduce the motion blur.

Furthermore, the (p + 4) th image 7315 and the (p + 5) th image 7316 may also be created from the (p + 3) th image 7314 and the (p + 6) th image 7317 using a similar method. That is, the (p + 4) th image 7315 and the (p + 5) th image 73
16 is an intermediate state of the (p + 3) th image 7314 and the (p + 6) th image 7317 by detecting the amount of change of the image from the (p + 3) th image 7314 to the (p + 6) th image 7317 It may be an image created as described above, and further, an image in which the brightness of the image is controlled according to a certain rule.

When the method of FIG. 73 (B) is used, since the display frame rate is large, the movement of the image can follow the movement of the eye well, and the movement of the image can be displayed smoothly. Can be significantly reduced.

In FIG. 73C, the display frame rate is 1.5 times the input frame rate (a conversion ratio of 1.5
Represents the case of). FIG. 73 (C) schematically shows the state of temporal change of the displayed image, where the horizontal axis is time. The image 7321 is the p-th image, the image 732
2 is the (p + 1) th image, the image 7323 is the (p + 2) th image, and the image 7324 is the (p +) image.
Suppose that it is the image of 3). Although the image 7325 may not actually be displayed, the image 7325 is input image data, and may be used to create the (p + 1) th image 7322 and the (p + 2) th image 7323. The period Tin represents the period of input image data. Note that since FIG. 73C shows the case where the conversion ratio is 1.5, the period Tin is
The length is 1.5 times the period until the (p + 1) th image is displayed after the pth image is displayed.

Here, the (p + 1) th image 7322 and the (p + 2) th image 7323 are detected by detecting the amount of change in the image from the pth image 7321 to the (p + 3) th image 7324 via the image 7325. , And an image created so as to be in an intermediate state between the p-th image 7321 and the (p + 3) -th image 7324. In FIG. 73C, the state of the image in the intermediate state is represented by a region (a circular region) in which the position changes according to the frame and a region (a triangle region) in which the position does not substantially change according to the frame. That is, the position of the circular area in the (p + 1) th image 7322 and the (p + 2) th image 7323 is the pth image 7
This position is intermediate between the position in 321 and the position in the (p + 3) th image 7324. That is, the (p + 1) th image 7322 and the (p + 2) th image 7323 are obtained by performing motion compensation and interpolating image data. As described above, by performing motion compensation on an object moving on an image and interpolating image data, smooth display can be performed.

Further, the (p + 1) th image 7322 and the (p + 2) th image 7323 are created to be in the intermediate state between the pth image 7321 and the (p + 3) th image 7324 and the brightness of the image is constant. It may be an image controlled by the rule of. The certain rule is, for example, FIG.
As in 3 (C), the representative luminance of the p-th image 7321 is L, the (p + 1) -th image 732
Assuming that the representative luminance of 2 is Lc1 and the representative luminance of the (p + 2) th image 7323 is Lc2, L> Lc1 or L> Lc2 or Lc1 = Lc2 in L, Lc1 and Lc2.
There may be a relationship. Desirably, there may be a relation of 0.1L <Lc1 = Lc2 <0.8L. More desirably, there may be a relationship of 0.2L <Lc = Lc2 <0.5L. Or, conversely, in L, Lc1, Lc2, L <Lc1 or L <Lc2
Alternatively, there may be a relationship of Lc1 = Lc2. Desirably, 0.1 Lc1 = 0.1 L
There may be a relationship of c2 <L <0.8 Lc1 = 0.8 Lc2. More preferably,
There may be a relationship of 0.2Lc1 = 0.2Lc2 <L <0.5Lc1 = 0.5Lc2. By doing so, since the display can be simulated in an impulse type, it is possible to suppress the afterimage of the eye. Alternatively, images in which the brightness is changed may be alternately displayed. By doing this, it is possible to shorten the cycle in which the luminance changes, so it is possible to reduce flicker.

Thus, two different causes for motion blur (the motion of the image is not smooth,
By solving the image and the afterimage of the eye at the same time, it is possible to significantly reduce the motion blur.

Note that when the method in FIG. 73C is used, since the display frame rate is small, the time for writing a signal to the display device can be lengthened. Therefore, since the clock frequency of the display device can be reduced, power consumption can be reduced. In addition, since the processing speed for performing motion compensation can be reduced, power consumption can be reduced.

Next, with reference to FIG. 74, representative luminance of the image will be described. 74 (A) through (D)
The figure shown in) schematically represents the state of temporal change of the displayed image, with the horizontal axis as time. FIG. 74E shows an example of a method of measuring the luminance of an image in a certain area.

As a method of measuring the brightness of the image, there is a method of measuring the brightness individually for each of the pixels constituting the image. Using this method, it is possible to measure the brightness precisely to the details of the image.

However, since the method of measuring the luminance individually for each of the pixels constituting the image is very laborious, another method may be used. Another way to measure the brightness of an image is to focus on an area in the image and measure the average brightness of that area. By this method, the brightness of the image can be easily measured. In the present embodiment, the luminance obtained by the method of measuring the average luminance of a certain area in an image is conveniently referred to as the representative luminance of the image.

Then, in order to obtain representative luminance of an image, a point as to which region in the image is to be focused will be described below.

FIG. 74A shows an example of a method of setting the luminance of the area (triangular area) whose position does not substantially change with respect to the change of the image as the representative luminance of the image. The period Tin is the period of the input image data, the image 7401 is the p-th image, the image 7402 is the (p + 1) -th image, the image 7403 is the (p + 2) -th image, the first region 7404 is the luminance in the p-th image 7401 The measurement area, the second area 7405 is the luminance measurement area in the (p + 1) th image 7402, the third area 74
06 represents the luminance measurement area in the (p + 2) th image 7403. Here, the first to third regions may be approximately the same as the spatial position in the device.
That is, by measuring the representative luminance of the image in the first to third regions, it is possible to determine the representative temporal change of the luminance of the image.

By measuring the representative luminance of the image, it can be determined whether the display is pseudo-impulse-type. For example, the luminance measured in the first region 7404 may be L, the second
Assuming that the luminance measured in the area 7405 of is Lc, if Lc <L, it can be said that the display is pseudo-impulse type. At this time, it can be said that the quality of moving pictures is improved.

In the luminance measurement region, the image quality can be improved when the representative amount of change in luminance (relative luminance) with respect to the change in time is in the following range. As the relative luminance, for example, the first area 7404 and the second area 7405, and the second area 7405 and the third area 7 can be used.
For each of the first area 7404 and the third area 7406, the ratio of the smaller luminance to the larger luminance can be used. That is, when the typical amount of change in luminance of the image with respect to the change in time is 0, the relative luminance is 100%. And the relative brightness is 8
If it is 0% or less, the quality of the moving image can be improved. In particular, if the relative luminance is 50% or less, the quality of moving pictures can be significantly improved. Furthermore, if the relative luminance is 10% or more, power consumption can be reduced and flicker can be suppressed. In particular, when the relative luminance is 20% or more, the power consumption and the flicker can be significantly reduced. That is, relative brightness is 10% or more and 80
If it is less than%, it is possible to improve the quality of moving pictures and reduce power consumption and flicker. Furthermore, if the relative luminance is 20% or more and 50% or less, the quality of moving images can be significantly improved, and power consumption and flicker can be significantly reduced.

FIG. 74B shows an example of a method of measuring the luminance of the tile-divided area and using the average value as the representative luminance of the image. Period Tin is a period of input image data, image 7411
Is the pth image, the image 7412 is the (p + 1) th image, the image 7413 is the (p + 2) th image, the first region 7414 is the luminance measurement region in the pth image 7411, and the second region 7415
Is the luminance measurement area in the (p + 1) th image 7412, and the third area 7416 is the
The luminance measurement areas in the image 7413 of FIG. Here, the first to third
The region of may be approximately the same as the spatial position in the device. That is, by measuring the representative luminance of the image in the first to third regions, it is possible to determine the representative temporal change of the luminance of the image.

By measuring the representative luminance of the image, it can be determined whether the display is pseudo-impulse-type. For example, assuming that the average value of all the luminances measured in the first region 7414 is L, and the average value of all the luminances measured in the second region 7415 is Lc, Lc <L. For example, it can be said that the display is pseudo impulse type.
At this time, it can be said that the quality of moving pictures is improved.

In the luminance measurement region, the image quality can be improved when the representative amount of change in luminance (relative luminance) with respect to the change in time is in the following range. As the relative luminance, for example, the first area 7414 and the second area 7415, the second area 7415 and the third area 7 can be used.
In each of the first area 7414 and the third area 7416, the ratio of the smaller luminance to the larger luminance can be used. That is, when the typical amount of change in luminance of the image with respect to the change in time is 0, the relative luminance is 100%. And the relative brightness is 8
If it is 0% or less, the quality of the moving image can be improved. In particular, if the relative luminance is 50% or less, the quality of moving pictures can be significantly improved. Furthermore, if the relative luminance is 10% or more, power consumption can be reduced and flicker can be suppressed. In particular, when the relative luminance is 20% or more, the power consumption and the flicker can be significantly reduced. That is, relative brightness is 10% or more and 80
If it is less than%, it is possible to improve the quality of moving pictures and reduce power consumption and flicker. Furthermore, if the relative luminance is 20% or more and 50% or less, the quality of moving images can be significantly improved, and power consumption and flicker can be significantly reduced.

FIG. 74C shows an example of a method of measuring the luminance of the central region of the image and using the average value as the representative luminance of the image. The period Tin is the period of the input image data, the image 7421 is the p-th image, the image 7422 is the (p + 1) -th image, the image 7423 is the (p + 2) -th image, the first region 7424 is the luminance in the p-th image 7421 The measurement area, the second area 7425 is the second (p
The third area 7426 represents the luminance measurement area in the (p + 2) th image 7423 in the +1) image 7422.

By measuring the representative luminance of the image, it can be determined whether the display is pseudo-impulse-type. For example, the luminance measured in the first region 7424 is L, the second
Assuming that the luminance measured in the area 7425 of Lc is Lc, if Lc <L, it can be said that the display is pseudo-impulse type. At this time, it can be said that the quality of moving pictures is improved.

In the luminance measurement region, the image quality can be improved when the representative amount of change in luminance (relative luminance) with respect to the change in time is in the following range. As the relative luminance, for example, a first area 7424 and a second area 7425, a second area 7425 and a third area 7
In each of the first area 7424 and the third area 7426, the ratio of the smaller luminance to the larger luminance can be used. That is, when the typical amount of change in luminance of the image with respect to the change in time is 0, the relative luminance is 100%. And the relative brightness is 8
If it is 0% or less, the quality of the moving image can be improved. In particular, if the relative luminance is 50% or less, the quality of moving pictures can be significantly improved. Furthermore, if the relative luminance is 10% or more, power consumption can be reduced and flicker can be suppressed. In particular, when the relative luminance is 20% or more, the power consumption and the flicker can be significantly reduced. That is, relative brightness is 10% or more and 80
If it is less than%, it is possible to improve the quality of moving pictures and reduce power consumption and flicker. Furthermore, if the relative luminance is 20% or more and 50% or less, the quality of moving images can be significantly improved, and power consumption and flicker can be significantly reduced.

FIG. 74D shows an example of a method of measuring the luminances of a plurality of points sampled from the entire image and using the average value as the representative luminance of the image. Period Tin is a cycle of input image data,
The image 7431 is the p-th image, the image 7432 is the (p + 1) -th image, the image 7433 is the
The second area 7434 is the luminance measurement area in the p-th image 7431. The second area 7435 is the luminance measurement area in the (p + 1) th image 7432. The third area 7436.
Denotes the luminance measurement area in the (p + 2) -th image 7433.

By measuring the representative luminance of the image, it can be determined whether the display is pseudo-impulse-type. For example, assuming that the average value of all the luminances measured in the first region 7434 is L, and the average value of all the luminances measured in the second region 7435 is Lc, Lc <L. For example, it can be said that the display is pseudo impulse type.
At this time, it can be said that the quality of moving pictures is improved.

In the luminance measurement region, the image quality can be improved when the representative amount of change in luminance (relative luminance) with respect to the change in time is in the following range. As the relative luminance, for example, a first area 7434 and a second area 7435, a second area 7435 and a third area 7
In each of the first area 7434 and the third area 7436, the ratio of the smaller luminance to the larger luminance can be obtained. That is, when the typical amount of change in luminance of the image with respect to the change in time is 0, the relative luminance is 100%. And the relative brightness is 8
If it is 0% or less, the quality of the moving image can be improved. In particular, if the relative luminance is 50% or less, the quality of moving pictures can be significantly improved. Furthermore, if the relative luminance is 10% or more, power consumption can be reduced and flicker can be suppressed. In particular, when the relative luminance is 20% or more, the power consumption and the flicker can be significantly reduced. That is, relative brightness is 10% or more and 80
If it is less than%, it is possible to improve the quality of moving pictures and reduce power consumption and flicker. Furthermore, if the relative luminance is 20% or more and 50% or less, the quality of moving images can be significantly improved, and power consumption and flicker can be significantly reduced.

FIG. 74E is a diagram showing a measurement method in the luminance measurement region in the diagrams shown in FIGS. 74A to 74D. An area 7441 is a luminance measurement area of interest, and a point 7442 is a luminance measurement point in the luminance measurement area 7441. As the luminance measurement device with high time resolution may have a small measurement target range, when the area 7441 is large, it does not measure the entire area, but as shown in FIG. The brightness may be measured at a plurality of points without any bias, and the average value may be used as the luminance of the region 7441.

When the image has a combination of three primary colors of R, G and B, the measured luminance is R and G.
, And B may be combined luminance, R and G combined luminance, G and B combined luminance, and B and R combined luminance, or each of R, G, and B. It may be luminance.

Next, a method of detecting an image movement included in input image data and creating an intermediate state image,
A method of controlling the driving method in accordance with the movement of the image included in the input image data will be described.

An example of a method of detecting an image movement included in input image data and creating an intermediate state image will be described with reference to FIG. FIG. 75A shows the case where the display frame rate is twice the input frame rate (the conversion ratio is 2). FIG. 75 (A) schematically shows a method of detecting the movement of the image with the horizontal axis representing time. A period Tin is a period of input image data, an image 7501 is a p-th image, an image 7502 is a (p + 1) -th image,
An image 7503 represents the (p + 2) -th image, respectively. Further, in the image, a first region 7504, a second region 7505 and a third region 750 are used as time-independent regions.
Provide six.

First, in the (p + 2) -th image 7503, the image is divided into a plurality of tile-like regions,
Attention is focused on image data in a third area 7506 which is one of them.

Next, in the p-th image 7501, a third area 750 centered on the third area 7506.
Focus on a range larger than 6. Here, the third area 7 centered on the third area 7506
The range greater than 506 is the data search range. The data search range is 7507 in the horizontal direction (X direction) and 7508 in the vertical direction (Y direction). The horizontal range 7507 and the vertical range 7508 of the data search range may be a range obtained by expanding the horizontal range and the vertical range of the third region 7506 by about 15 pixels.

Then, in the data search range, a region having image data most similar to the image data in the third region 7506 is searched. The search method can use the least squares method or the like. As a result of the search, it is assumed that a first area 7504 is derived as an area having the most similar image data.

Next, a vector 7509 is derived as a quantity representing the difference in position between the derived first area 7504 and the third area 7506. The vector 7509 is called a motion vector.

Then, in the (p + 1) -th image 7502, a vector 7510 obtained from the motion vector 7509, image data in a third region 7506 in the (p + 2) -th image 7503, and a first in the p-th image 7501. A second region 7505 is formed by the image data in the region 7504.

Here, the vector 7510 obtained from the motion vector 7509 is referred to as a displacement vector. The displacement vector 7510 has a role of determining the position forming the second region 7505. Second region 7505 is formed at a position spaced apart from third region 7506 by displacement vector 7510. The displacement vector 7510 has a coefficient (1/2) to the motion vector 7509.
The amount may be multiplied.

The image data in the second area 7505 of the (p + 1) th image 7502 is the
And the image data in the first region 7504 in the p-th image 7501. For example,
The image data in the second area 7505 of the (p + 1) th image 7502 is the
And the average value of the image data in the first region 7504 in the p-th image 7501.

Thus, corresponding to the third region 7506 in the (p + 2) th image 7503,
A second region 7505 in the (p + 1) th image 7502 can be formed. Note that the above process is performed on other regions in the (p + 2) -th image 7503 as well.
An (p + 1) th image 7 intermediate the image 7503 of the p + 2) and the pth image 7501
502 can be formed.

FIG. 75B shows the case where the display frame rate is three times the input frame rate (the conversion ratio is 3). FIG. 75 (B) schematically shows a method of detecting the movement of the image with the horizontal axis as time. Period Tin is a period of input image data, image 7511
Represents the p-th image, the image 7512 represents the (p + 1) -th image, the image 7513 represents the (p + 2) -th image, and the image 7514 represents the (p + 3) -th image. In addition, in the image, a first region 7515, a second region 7516, and a third region 7517 are used as time-independent regions.
And a fourth region 7518.

First, in the (p + 3) th image 7514, the image is divided into a plurality of tile-like areas,
The image data in the fourth area 7518 which is one of the areas is focused.

Next, in the p-th image 7511, a fourth region 751 centered on the fourth region 7518.
Focus on a range larger than eight. Here, the fourth area 7 centered on the fourth area 7518
The range greater than 518 is the data search range. The data search range is 7519 in the horizontal direction (X direction), and 7520 in the vertical direction (Y direction). The horizontal range 7519 and the vertical range 7520 of the data search range may be a range obtained by expanding the horizontal range and the vertical range of the fourth region 7518 by about 15 pixels.

Then, within the data search range, a region having image data most similar to the image data in the fourth region 7518 is searched. The search method can use the least squares method or the like. It is assumed that the first area 7515 is derived as an area having the most similar image data as a result of the search.

Next, a vector 7521 is derived as a quantity representing the difference in position between the derived first area 7515 and the fourth area 7518. The vector 7521 will be referred to as a motion vector.

In the (p + 1) th image 7512 and the (p + 2) th image 7513,
By the vectors 7522 and 7523 obtained from the motion vector 7521, the image data in the fourth region 7518 in the (p + 3) th image 7515, and the image data in the first region 7515 in the pth image 7511, A second region 7516 and a third region 7517 are formed.

Here, the vector 7522 obtained from the motion vector 7521 is referred to as a first displacement vector. Also, the vector 7523 is referred to as a second displacement vector. The first displacement vector 7522 has a role of determining the position forming the second region 7516. The second region 7516 is formed at a position separated from the fourth region 7518 by the first displacement vector 7522. The displacement vector 7522 may be an amount obtained by multiplying the motion vector 7521 by (1/3). In addition, the second displacement vector 7523 has a role of determining the position where the third region 7517 is formed. The third area 7517 is formed at a position separated from the fourth area 7518 by the second displacement vector 7523. The displacement vector 7523 may be an amount obtained by multiplying the motion vector 7521 by (2/3).

The image data in the second area 7516 of the (p + 1) th image 7512 is the (p + 3) th image.
And the image data in the first area 7515 in the p-th image 7511. For example,
The image data in the second area 7516 of the (p + 1) th image 7512 is the (p + 3) th image.
And the average value of the image data in the first region 7515 in the p-th image 7511.

The image data in the third region 7517 of the (p + 2) th image 7513 is the (p + 3) th image.
And the image data in the first area 7515 in the p-th image 7511. For example,
The image data in the third region 7517 of the (p + 2) th image 7513 is the (p + 3) th image.
And the average value of the image data in the first region 7515 in the p-th image 7511.

Thus, corresponding to the fourth region 7518 in the (p + 3) th image 7514,
Second region 7516 in the (p + 1) th image 7502 and the (p + 2) th image 7
A third region 7517 at 513 can be formed. In addition, the above processing
The (p + 3) th image 751 is obtained by performing the processing also on other regions in the p + 3) image 7514.
The (p + 1) th image 7512 and the (p +) th image 7512 that are intermediate states of the 4th and the p-th images 7511
The image 7513 of 2) can be formed.

Next, with reference to FIG. 76, an example of a circuit for detecting the movement of an image included in input image data and creating an intermediate state image will be described. FIG. 76A illustrates a connection between a source driver for displaying an image in a display region, a peripheral driver circuit including a gate driver, and a control circuit for controlling the peripheral driver circuit. FIG. 76B is a diagram showing an example of a detailed circuit configuration of the control circuit. FIG. 76C is a diagram showing an example of a detailed circuit configuration of an image processing circuit included in the control circuit. FIG. 76D shows another example of the detailed circuit configuration of the image processing circuit included in the control circuit.

As in FIG. 76A, the device in this embodiment may include a control circuit 7611, a source driver 7612, a gate driver 7613, and a display area 7614.

Note that the control circuit 7611, the source driver 7612, and the gate driver 7613 may be formed over the same substrate as the display region 7614 is formed.

Note that among the control circuit 7611, the source driver 7612, and the gate driver 7613, some of them are formed on the same substrate as the substrate on which the display region 7614 is formed.
Other circuits may be formed on a substrate different from the substrate on which the display region 7614 is formed. For example, the source driver 7612 and the gate driver 7613 may be formed on the same substrate as the display region 7614, and the control circuit 7611 may be formed as an external IC on a different substrate. Similarly, the gate driver 7613 may be formed on the same substrate as the display region 7614 is formed, and the other circuits may be formed as an external IC on a different substrate. Similarly, source driver 7612
The gate driver 7613 and part of the control circuit 7611 may be formed on the same substrate as the display region 7614, and the other circuits may be formed as external ICs on different substrates.

The control circuit 7611 receives an external image signal 7600, a horizontal synchronization signal 7601, and a vertical synchronization signal 7602, and receives an image signal 7603, a source start pulse 7604, a source clock 7605, a gate start pulse 7606, and a gate. Clock 7607,
May be output.

The source driver 7612 may be configured to receive an image signal 7603, a source start pulse 7604, and a source clock 7605, and output a voltage or current according to the image signal 7603 to the display area 7614.

The gate driver 7613 has a gate start pulse 7606 and a gate clock 7607.
And may be input, and a signal may be output which specifies the timing at which the signal output from the source driver 7612 is written to the display area 7614.

When the frequency of the external image signal 7600 is different from the frequency of the image signal 7603, signals for controlling the timing for driving the source driver 7612 and the gate driver 7613 are also input horizontal synchronization signal 7601 and vertical synchronization signal 7602 It will have different frequencies. Therefore, in addition to the processing of the image signal 7603, a signal for controlling the timing of driving the source driver 7612 and the gate driver 7613 needs to be processed. The control circuit 7611 may be a circuit having a function therefor. For example, when the frequency of the image signal 7603 is double the frequency of the external image signal 7600, the control circuit 7611 interpolates the image signal included in the external image signal 7600 to generate an image signal 7603 with a double frequency. And the signal for controlling the timing is also controlled to have a double frequency.

Further, as shown in FIG. 76B, the control circuit 7611 may include an image processing circuit 7615 and a timing generation circuit 7616.

The image processing circuit 7615 may be configured such that an external image signal 7600 and a frequency control signal 7608 are input and an image signal 7603 is output.

The timing generation circuit 7616 receives the horizontal synchronization signal 7601 and the vertical synchronization signal 7602, and receives a source start pulse 7604, a source clock 7605, a gate start pulse 7606, a gate clock 7607, and a frequency control signal 7608, May be output. Timing generation circuit 7616 receives frequency control signal 760.
A memory or register that holds data for specifying the state of 8 may be included. Further, the timing generation circuit 7616 may be configured to be input with a signal specifying the state of the frequency control signal 7608 from the outside.

As illustrated in FIG. 76C, the image processing circuit 7615 includes a motion detection circuit 7620, a first memory 7621, a second memory 7622, a third memory 7623, and a luminance control circuit 762.
3 and a high speed processing circuit 7625 may be included.

The motion detection circuit 7620 may be configured to receive a plurality of image data, detect a motion of the image, and output image data in an intermediate state of the plurality of image data.

The first memory 7621 receives an external video signal 7600 and the external video signal 7600.
The external video signal 7600 may be output to the motion detection circuit 7620 and the second memory 7622 while holding the signal for a fixed period.

The second memory 7622 receives the image data output from the first memory 7621,
The image data may be output to the motion detection circuit 7620 and the high-speed processing circuit 7625 while holding the image data for a fixed period.

The third memory 7623 receives the image data output from the motion detection circuit 7620,
The image data may be output to the luminance control circuit 7624 while holding the image data for a certain period.

The high-speed processing circuit 7625 receives the image data output from the second memory 7622, the image data output from the luminance control circuit 7624, and the frequency control signal 7608, and sets the image data as the image signal 7603. It may be configured to output.

When the frequency of the external image signal 7600 and the frequency of the image signal 7603 are different, the image processing circuit 7615 may generate the image signal 7603 by interpolating the image signal included in the external image signal 7600. The input external image signal 7600 is temporarily stored in the first memory 7.
It is held at 621. At that time, the second memory 7622 holds the image data input in the previous frame. The motion detection circuit 7620 appropriately reads the image data stored in the first memory 7621 and the second memory 7622, detects a motion vector from the difference between the image data of both, and further generates image data in an intermediate state. May be The generated intermediate state image data is held by the third memory 7623.

When the motion detection circuit 7620 is generating intermediate state image data, the high speed processing circuit 762
5 outputs the image data held in the second memory 7622 as an image signal 7603. Thereafter, the image data held in the third memory 7623 is subjected to the luminance control circuit 7624.
Output as an image signal 7603. At this time, the second memory 7622 and the third
The frequency at which the memory 7623 is updated is the same as the frequency of the external image signal 7600, but the frequency of the image signal 7603 output through the high speed processing circuit 7625 is the frequency of the external image signal 760.
It may be different from 0 frequency. Specifically, for example, the frequency of the image signal 7603 may be 1.5, 2 or 3 times the frequency of the external image signal 7600. However, the frequency is not limited to this and various frequencies can be used. Note that the frequency of the image signal 7603 may be designated by the frequency control signal 7608.

The configuration of the image processing circuit 7615 shown in FIG. 76D is obtained by adding a fourth memory 7626 to the configuration of the image processing circuit 7615 shown in FIG. 76C. Thus, in addition to the image data output from the first memory 7621 and the image data output from the second memory 7622, the image data output from the fourth memory 7626 is also motion detection circuit 7620.
By outputting to, it becomes possible to detect the motion of the image accurately.

When the input image data already includes a motion vector for data compression etc., for example, MPEG (Moving Picture Expert Gr)
In the case of image data based on the oup) standard, an intermediate state image may be generated as an interpolated image using this. At this time, a portion for generating a motion vector, which is included in the motion detection circuit 7620, becomes unnecessary. In addition, since the encoding and decoding processes related to the image signal 7623 can be simplified, power consumption can be reduced.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of this embodiment can be applied to, combined with, or replaced with the contents (or a part) described in the figure of another embodiment. Can do it freely. Furthermore, in the drawings of the present embodiment, more parts can be configured by combining the parts of the other embodiments with respect to the respective parts.

Note that this embodiment is an example in the case of embodying the contents (may be a part) described in the other embodiments, an example in the case of slight modification, an example in the case of changing a part, an improvement An example of the case,
An example of the case described in detail, an example of the case of application, an example of the relevant part, and the like are shown. Therefore, the contents described in the other embodiments can be freely applied to, combined with, or replaced with this embodiment.

(Embodiment 11)
In this embodiment mode, a structure and a manufacturing method of a transistor will be described.

FIG. 48 shows an example of a structure of a transistor included in a display device according to the present invention and a method of manufacturing the same. FIG. 48A illustrates an example of a structure of a transistor included in a display device according to the present invention. 48B to 48G illustrate an example of a method for manufacturing a transistor included in the display device according to the present invention.

Note that the structure and manufacturing method of the transistor included in the display device according to the present invention are not limited to those illustrated in FIG. 48, and various structures and manufacturing methods can be used.

First, an example of a structure of a transistor included in a display device according to the present invention will be described with reference to FIG. FIG. 48A is a cross-sectional view of a transistor having a plurality of different structures. Here, FIG. 48A shows a plurality of juxtaposed transistors having different structures, which is for describing a structure of a transistor included in a display device according to the present invention, and in practice It is not necessary to be juxtaposed as shown in FIG. 48 (A), and can be made separately as needed.

Next, each layer constituting a transistor included in the display device according to the present invention will be described.

As the substrate 4011, a glass substrate such as barium borosilicate glass or aluminoborosilicate glass, a quartz substrate, a ceramic substrate, a metal substrate containing stainless steel, or the like can be used.
Besides, polyethylene terephthalate (PET), polyethylene naphthalate (PEN)
It is also possible to use a substrate made of a plastic represented by polyether sulfone (PES) or a flexible synthetic resin such as acrylic. By using a flexible substrate, a display device which can be bent can be manufactured.

The insulating film 4012 functions as a base film. This base film is provided to prevent an alkali metal or an alkaline earth metal such as Na from the substrate 4011 from adversely affecting the characteristics of the semiconductor element. An insulating film containing oxygen or nitrogen, such as silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy) (x> y), silicon nitride oxide (SiNxOy) (x> y), or the like as the insulating film 4012 It can be provided in a single layer structure or a laminated structure of these.
For example, in the case where the insulating film 4012 is provided to have a two-layer structure, a silicon nitride oxide film may be provided as a first insulating film and a silicon oxynitride film may be provided as a second insulating film. In the case where the insulating film 4012 is provided in a three-layer structure, a silicon oxynitride film is provided as a first insulating film, a silicon nitride oxide film is provided as a second insulating film, and oxynitride is formed as the third insulating film. It is preferable to provide a silicon film.

The semiconductor layers 4013, 4014, and 4015 can be formed using an amorphous (amorphous) semiconductor or a semi-amorphous semiconductor (SAS). Alternatively, a polycrystalline semiconductor layer may be used. SAS has an intermediate structure between amorphous and crystalline (including single crystal and polycrystal),
A semiconductor having a free energy stable third state, which includes crystalline regions having short-range order and lattice distortion. 0.5 to 20 at least in some areas in the membrane
A crystalline region of nm can be observed, and when silicon is the main component, the Raman spectrum is shifted to a lower wave number side than 520 cm ⁻¹ . In X-ray diffraction, diffraction peaks of (111) and (220) which are considered to be derived from the silicon crystal lattice are observed. At least 1 atomic% or more of hydrogen or halogen is included as compensation for dangling bonds. SAS is formed by glow discharge decomposition (plasma CVD) of a source gas. As the material gas, SiH ₄ and others, Si ₂ H ₆ , SiH ₂ Cl ₂ , SiHCl ₃ , SiC
It is possible to use l ₄ , SiF ₄ or the like. Alternatively, GeF ₄ may be mixed. This material gas may be diluted with H ₂ , or H ₂ and one or more kinds of rare gas elements selected from He, Ar, Kr, and Ne. The dilution rate is in the range of 2 to 1000 times. The pressure is approximately 0.
The power supply frequency is in the range of 1 MHz to 120 MHz, preferably 13 MHz.
z to 60 MHz. The substrate heating temperature may be 300 ° C. or less. As an impurity element in the film, oxygen,
It is desirable that the impurities of atmospheric components such as nitrogen and carbon be 1 × 10 ²⁰ cm ⁻¹ or less,
In particular, the oxygen concentration is 5 × 10 ¹⁹ / cm ³ or less, preferably 1 × 10 ¹⁹ / cm ³ or less. Here, an amorphous semiconductor layer is formed of a material (for example, SixGe1-x or the like) whose main component is silicon (Si) using a known method (a sputtering method, an LPCVD method, a plasma CVD method, or the like). The crystalline semiconductor layer is crystallized by a known crystallization method such as a laser crystallization method, an RTA or a thermal crystallization method using a furnace for annealing, or a thermal crystallization method using a metal element promoting crystallization.

The insulating film 4016 is made of silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (Si)
A single layer structure of an insulating film containing oxygen or nitrogen such as OxNy) (x> y), silicon nitride oxide (SiNxOy) (x> y), or a stacked structure thereof can be provided.

The gate electrode 4017 can have a single-layer conductive film or a stacked-layer structure of two or three conductive films. A known conductive film can be used as a material of the gate electrode 4017. For example, tantalum (Ta), titanium (Ti), molybdenum (Mo), tungsten (
W) a single film of an element such as chromium (Cr) or silicon (Si), or a nitride film of the above element (typically a tantalum nitride film, a tungsten nitride film, a titanium nitride film), or a combination of the above elements Alloy film (typically Mo-W alloy, Mo-Ta alloy), or
Silicide film of the above elements (typically tungsten silicide film, titanium silicide film)
Etc. can be used. Note that the single film, the nitride film, the alloy film, the silicide film, and the like described above may be used as a single layer or may be stacked.

The insulating film 4018 is formed of silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy) (x> y), silicon nitride oxide (SiNxOy) (SiNxOy) by a known method (such as sputtering or plasma CVD). It can be provided as a single layer structure of an insulating film having oxygen or nitrogen such as x> y) or a film containing carbon such as DLC (diamond like carbon) or a laminated structure of these.

The insulating film 4019 is a siloxane resin, or silicon oxide (SiO x), silicon nitride (Si
Nx), silicon oxynitride (SiOx Ny) (x> y), silicon nitride oxide (SiN x Oy) (x
> Y) Insulating films having oxygen or nitrogen, carbon containing films such as DLC (diamond like carbon), or organic materials such as epoxy, polyimide, polyamide, polyvinyl phenol, benzocyclobutene, acrylic, etc. It can provide in the single layer or laminated structure which consists of ,. Note that the siloxane resin corresponds to a resin containing a Si-O-Si bond. Siloxane has a skeletal structure formed by the bond of silicon (Si) and oxygen (O). As a substituent, an organic group containing at least hydrogen (for example, an alkyl group or an aryl group) is used. A fluoro group can also be used as a substituent. Alternatively, as a substituent, an organic group containing at least hydrogen and a fluoro group may be used. Note that in the display device that can be applied to the present invention, the insulating film 4019 can be provided directly so as to cover the gate electrode 4017 without providing the insulating film 4018.

The conductive film 4023 may be a single film of an element such as Al, Ni, W, Mo, Ti, Pt, Cu, Ta, Au, or Mn, a nitride film of the above element, an alloy film combining the above elements, or And silicide films of the above elements can be used. For example, as an alloy containing a plurality of the above elements, an Al alloy containing C and Ti, an Al alloy containing Ni, C and N
An Al alloy containing i, an Al alloy containing C and Mn, or the like can be used. Also,
In the case of providing a stacked structure, Al can be sandwiched by Mo, Ti, or the like.
This can improve the resistance of Al to heat and chemical reaction.

Next, characteristics of each structure are described with reference to cross-sectional views of the transistors having a plurality of different structures illustrated in FIG.

The transistor 4001 is a single drain transistor and can be manufactured by a simple method; therefore, there is an advantage that manufacturing cost is low and manufacturing can be performed with high yield. Here, the semiconductor layer 4
In 013 and 4015, the concentrations of impurities are different, and the semiconductor layer 4013 functions as a channel region and the semiconductor layer 4015 functions as a source region and a drain region. Thus, by controlling the amount of impurities, the resistivity of the semiconductor layer can be controlled. In addition, the state of electrical connection between the semiconductor layer and the conductive film 4023 can be closer to ohmic connection. Note that
As a method of separately forming semiconductor layers having different amounts of impurities, a method of doping the semiconductor layer with impurities using the gate electrode 4017 as a mask can be used.

The transistor 4002 is a transistor in which the gate electrode 4017 has a taper angle greater than or equal to a predetermined angle, and can be manufactured by a simple method. Therefore, the transistor 4002 has advantages of low manufacturing cost and high yield. The semiconductor layers 4013, 4014, and 4015 have different impurity concentrations, and the semiconductor layer 4013 has a channel region, and the semiconductor layer 4014 has a low concentration drain (Lightl).
y Doped Drain (LDD) region, and the semiconductor layer 4015 is used as a source region and a drain region. Thus, the resistivity of the semiconductor layer can be controlled by controlling the amount of impurities. In addition, the state of electrical connection between the semiconductor layer and the conductive film 4023 can be closer to ohmic connection. In addition, since the LDD region is provided, a high electric field is not easily applied to the inside of the transistor, and deterioration of the element due to hot carriers can be suppressed. Note that as a method of separately forming semiconductor layers with different amounts of impurities, a method of doping an impurity into a semiconductor layer can be used by using the gate electrode 4017 as a mask. In the transistor 4002, since the gate electrode 4017 has a taper angle, the concentration of an impurity which passes through the gate electrode 4017 and is doped to the semiconductor layer can have a gradient, which easily forms an LDD region. can do.

The transistor 4003 includes a gate electrode of at least two layers, and the lower gate electrode 4
The transistor 017a has a shape longer than that of the upper gate electrode 4017b. In the present specification, the shapes of the upper gate electrode and the lower gate electrode are referred to as a cap shape.
Since the shape of the gate electrode is hat-shaped, the LDD can be added without adding a photo mask.
Regions can be formed. Note that as in the transistor 4003, a structure in which the LDD region overlaps with the gate electrode has a GOLD structure (Gate Overlapped L).
It is called DD). As a method of making the shape of the gate electrode into a hat shape, the following method may be used.

First, when the gate electrode is patterned, the gate electrode in the lower layer and the gate electrode in the upper layer are etched by dry etching to form a shape having a slope on the side surface. Subsequently, the inclination of the upper gate electrode is processed to be close to vertical by anisotropic etching.
Thus, a gate electrode having a hat-shaped cross section is formed. After that, by doping the impurity element twice, a semiconductor layer 4013 used as a channel region, a semiconductor layer 4014 used as an LDD region, and a semiconductor layer 40 used as a source electrode and a drain electrode
15 are formed.

Note that an LDD region overlapping the gate electrode is referred to as a Lov region, and an LDD region not overlapping the gate electrode is referred to as a Loff region. Here, the Loff region has a high effect of suppressing the off current value, but has a low effect of alleviating the electric field in the vicinity of the drain to prevent the deterioration of the on current value due to hot carriers. On the other hand, although the Lov region is effective in reducing the electric field in the vicinity of the drain and preventing the deterioration of the on current value, the effect of suppressing the off current value is low. Therefore, it is preferable to manufacture a transistor having a structure in accordance with the required characteristics for each of various circuits. For example, in the case of using a display device that can be applied to the present invention as a display device, it is preferable that a pixel transistor be a transistor having an Loff region in order to suppress an off current value. On the other hand, in the transistor in the peripheral circuit, it is preferable to use a transistor having a Lov region in order to ease the electric field in the vicinity of the drain and to prevent the deterioration of the on current value.

The transistor 4004 is in contact with the side surface of the gate electrode 4017 and the side wall 4021.
Is a transistor having By having the side walls 4021, a region overlapping with the side walls 4021 can be made an LDD region.

The transistor 4005 can be formed by LDD by doping the semiconductor layer using a mask.
It is a transistor in which a (Loff) region is formed. By this, the LDD region can be surely formed, and the off current value of the transistor can be reduced.

The transistor 4006 is formed by LDD by doping the semiconductor layer using a mask.
It is a transistor in which a (Lov) region is formed. By this, the LDD region can be surely formed, 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, with reference to FIGS. 48B to 48G, an example of a method for manufacturing a transistor included in the display device according to the present invention will be described.

Note that the structure and manufacturing method of the transistor included in the display device according to the present invention are not limited to those illustrated in FIG. 48, and various structures and manufacturing methods can be used.

In this embodiment mode, the substrate 4011, the insulating film 4012, and the semiconductor layers 4013 and 4014 are used.
The surface of the insulating film 4016, the insulating film 4016, the insulating film 4018, and the insulating film 4019 can be oxidized or nitrided by performing oxidation or nitridation treatment using plasma treatment. Thus, the surface of the semiconductor layer or the insulating film is reformed by oxidizing or nitriding the semiconductor layer or the insulating film using plasma treatment, and the insulating film is formed by CVD or sputtering as compared with the insulating film. More dense insulating film can be formed. Therefore, it is possible to suppress defects such as pinholes and improve the characteristics and the like of the display device.

First, the surface of the substrate 4011 is cleaned using hydrofluoric acid (HF), alkali, or pure water. The substrate 4011 is a glass substrate such as barium borosilicate glass or aluminoborosilicate glass.
A quartz substrate, a ceramic substrate, a metal substrate containing stainless steel, or the like can be used. Besides, a substrate made of a plastic typified by polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyether sulfone (PES), or a flexible synthetic resin such as acrylic is also available. It is also possible to use. Note that a glass substrate is used as the substrate 4011 here.

Here, the surface of the substrate 4011 is oxidized or nitrided by plasma treatment.
An oxide film or a nitride film may be formed on the surface of (FIG. 48 (B)). Hereinafter, an insulating film such as an oxide film or a nitride film formed by performing plasma treatment on the surface is also referred to as a plasma processing insulating film. Note that in FIG. 48B, the insulating film 4031 is a plasma treatment insulating film. Generally, when a semiconductor element such as a thin film transistor is provided on a substrate such as glass or plastic, an impurity element such as an alkali metal such as Na or an alkaline earth metal contained in the glass or plastic is mixed into the semiconductor element. This may affect the characteristics of the semiconductor device. However, by nitriding the surface of the substrate made of glass, plastic or the like, it is possible to prevent the impurity element such as alkali metal or alkaline earth metal contained in the substrate from being mixed into the semiconductor element.

Note that in the case where the surface is oxidized by plasma treatment, oxygen atmosphere (for example, oxygen (O ₂
) Under a rare gas (containing at least one of He, Ne, Ar, Kr, and Xe), or under a rare gas atmosphere of oxygen and hydrogen (H ₂ ), or under an atmosphere of dinitrogen monoxide and a rare gas. )
Plasma treatment is performed. On the other hand, in the case where the semiconductor layer is nitrided by plasma treatment, for example, in a nitrogen atmosphere (for example, in an atmosphere of nitrogen (N ₂ ) and a rare gas (including at least one of He, Ne, Ar, Kr, and Xe), or Plasma treatment is performed under an atmosphere of nitrogen and hydrogen and a rare gas, or under an atmosphere of NH ₃ and a rare gas. As the rare gas, for example, Ar or a mixed gas of Ar and Kr can be used. Therefore, the plasma-treated insulating film contains a rare gas (including at least one of He, Ne, Ar, Kr, and Xe) used for plasma treatment. For example, in the case of using Ar, the plasma processing insulating film contains Ar.

In the plasma treatment, the electron density is 1 × 10 ¹¹ cm ^{−3 in the} above gas atmosphere.
1 × 10 ¹³ cm ⁻³ or less, and the plasma electron temperature is 0.5 eV to 1.5 eV
It is preferable to process below. This is because plasma electron density is high and electron temperature near the object to be treated is low, so that damage to the object to be treated by plasma can be prevented. In addition, since the electron density of plasma is as high as 1 × 10 ¹¹ cm ⁻³ or more,
An oxide or nitride film formed by oxidizing or nitriding an object to be irradiated using plasma treatment is superior in uniformity such as film thickness to a film formed by a CVD method, a sputtering method, or the like.
And, a dense film can be formed. Alternatively, since the plasma electron temperature is as low as 1 eV or less, oxidation or nitridation treatment can be performed at a lower temperature as compared to conventional plasma treatment and thermal oxidation. For example, even if plasma treatment is performed at a temperature lower by 100 ° C. or more than the strain point temperature of the glass substrate, sufficient oxidation or nitridation treatment can be performed. Note that a high frequency such as microwave (2.45 GHz) can be used as a frequency for forming plasma. Note that, unless otherwise specified below, the plasma treatment is performed using the above conditions.

Note that FIG. 48B shows the case where a plasma-treated insulating film is formed by plasma-treating the surface of the substrate 4011, but in this embodiment, a plasma-treated insulating film is formed on the surface of the substrate 4011. Also includes the case of not forming.

In FIGS. 48C to 48G, although a plasma processing insulating film formed by plasma processing the surface of the processing object is not shown, in this embodiment, the substrate 40 is not shown.
11 also includes the case where a plasma treatment insulating film formed by performing plasma treatment is present on the surface of the insulating film 4012, the semiconductor layer 4013, 4014, 4015, the insulating film 4016, the insulating film 4018, or the insulating film 4019.

Next, known means (sputtering method, LPCVD method, plasma CVD method, etc.) on the substrate 4011
To form an insulating film 4012 (FIG. 48C). As the insulating film 4012, silicon oxide (SiOx) or silicon oxynitride (SiOx Ny) (x> y) can be used.

Here, a plasma treatment insulating film may be formed on the surface of the insulating film 4012 by performing plasma treatment on the surface of the insulating film 4012 to oxidize or nitride the insulating film 4012. By oxidizing the surface of the insulating film 4012, the surface of the insulating film 4012 can be reformed to obtain a dense film with few defects such as pinholes. In addition, since the plasma-treated insulating film having a low content of N atoms can be formed by oxidizing the surface of the insulating film 4012, the plasma-treated insulating film and the semiconductor are provided when the semiconductor layer is provided on the plasma-treated insulating film. Layer interface properties are improved. Further, the plasma-treated insulating film is formed of the rare gas (He, Ne, Ar,
Containing at least one of Kr and Xe). Plasma treatment can be performed similarly under the conditions described above.

Next, island-shaped semiconductor layers 4013 and 4014 are formed over the insulating film 4012 (FIG. 48D)
). The island-shaped semiconductor layers 4013 and 4014 are made of a material (silicon (Si)) as a main component (the sputtering method, the LPCVD method, the plasma CVD method, etc.) on the insulating film 4012
For example, an amorphous semiconductor layer is formed using SixGe1-x or the like, or the like, the amorphous semiconductor layer is crystallized, and the semiconductor layer can be selectively etched. Note that
The crystallization of the amorphous semiconductor layer may be performed by laser crystallization, thermal crystallization using RTA or a furnace for annealing, thermal crystallization using a metal element that promotes crystallization, or a combination of these methods, etc. It can be carried out by the known crystallization method of Here, the end portions of the island-shaped semiconductor layers are provided in a shape close to a right angle (θ = 85 to 100 °). Alternatively, the semiconductor layer 4014 to be a low concentration drain region may be formed by doping an impurity using a mask.

Here, plasma treatment is performed on the surfaces of the semiconductor layers 4013 and 4014 to form a semiconductor layer 4013,
A plasma treatment insulating film may be formed on the surfaces of the semiconductor layers 4013 and 4014 by oxidizing or nitriding the surface of the semiconductor layer 4014. For example, Si as the semiconductor layers 4013 and 4014
Silicon oxide (SiO x) or silicon nitride (Si
x) is formed. Alternatively, the semiconductor layers 4013 and 4014 may be oxidized by plasma treatment and then nitrided by plasma treatment again. In this case, silicon oxide (SiOx) is formed in contact with the semiconductor layers 4013 and 4014, and silicon nitride oxide (SiNxOy) (x> y) is formed on the surface of the silicon oxide. Note that in the case where the semiconductor layer is oxidized by plasma treatment, oxygen atmosphere (for example, oxygen (O ₂ ) and a rare gas (He, Ne, A) are used.
r, Kr, including at least one) atmosphere of Xe, or oxygen and hydrogen (H ₂₎ and a rare gas, or dinitrogen monoxide and a rare gas atmosphere), in plasma processing is carried out. On the other hand, in the case where the semiconductor layer is nitrided by plasma treatment, for example, in a nitrogen atmosphere (for example, in an atmosphere of nitrogen (N ₂ ) and a rare gas (including at least one of He, Ne, Ar, Kr, and Xe), or Plasma treatment is performed under an atmosphere of nitrogen and hydrogen and a rare gas or under an atmosphere of NH 3 and a rare gas. For example, Ar can be used as the noble gas. Alternatively, a mixture of Ar and Kr may be used. Therefore, the plasma-treated insulating film is formed of the rare gas (He, Ne) used in the plasma treatment.
, Ar, Kr, and Xe). For example, in the case of using Ar, the plasma processing insulating film contains Ar.

Next, an insulating film 4016 is formed (FIG. 48E). The insulating film 4016 can be formed of silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOx Ny) (x> y), or oxynitride using a known method (sputtering, LPCVD, plasma CVD, etc.) Silicon (SiNx
A single-layer structure of an insulating film containing oxygen or nitrogen such as Oy) (x> y), or a stacked structure thereof can be provided. Note that in the case where a plasma treatment insulating film is formed on the surfaces of the semiconductor layers 4013 and 4014 by performing plasma treatment on the surfaces of the semiconductor layers 4013 and 4014,
It is also possible to use a plasma treatment insulating film as the insulating film 4016.

Here, plasma treatment may be performed on the surface of the insulating film 4016 to oxidize or nitride the surface of the insulating film 4016, thereby forming a plasma treatment insulating film on the surface of the insulating film 4016.
Note that the plasma processing insulating film is a rare gas (He, Ne, Ar, Kr, or the like) used for the plasma processing.
Containing at least one of Xe). Also, plasma processing can be performed under the conditions described above.

Alternatively, the insulating film 4016 may be oxidized by performing plasma treatment once in an oxygen atmosphere, and then may be nitrided by performing plasma treatment again in a nitrogen atmosphere. As described above, plasma treatment is performed on the insulating film 4016 to oxidize or nitride the surface of the insulating film 4016, whereby the surface of the insulating film 4016 can be reformed to form a dense film. An insulating film obtained by performing plasma treatment is denser and has fewer defects such as pinholes as compared with an insulating film formed by a CVD method or a sputtering method, so that the characteristics of the thin film transistor can be improved.

Next, a gate electrode 4017 is formed (FIG. 48F). The gate electrode 4017 can be formed by using a known method (a sputtering method, an LPCVD method, a plasma CVD method, or the like).

In the transistor 4001, the semiconductor layer 4015 which is used as a source region and a drain region can be formed by performing impurity doping after the gate electrode 4017 is formed.

In the transistor 4002, by performing impurity doping after forming the gate electrode 4017, the semiconductor layer 4013 used as an LDD region, the semiconductor layer 4013, and the semiconductor layer 4015 used as a source region and a drain region can be formed.

In the transistor 4003, after the gate electrodes 4017a and 4017b are formed, impurity doping is performed to form the semiconductor layers 4013 and 4013 which are used as LDD regions.
A semiconductor layer 4015 used as a source region and a drain region can be formed.

In the transistor 4004, the side wall 4021 is formed on the side surface of the gate electrode 4017.
And 4014 to be used as an LDD region by performing impurity doping.
The semiconductor layer 4013 and the semiconductor layer 4015 used as a source region and a drain region can be formed.

Note that silicon oxide (SiOx) or silicon nitride (SiNx) can be used as the side wall 4021. As a method of forming the side wall 4021 on the side surface of the gate electrode 4017, for example, after forming the gate electrode 4017, silicon oxide (SiOx) or silicon nitride (SiNx) is formed by a known method, Silicon oxide by reactive etching
A method of etching a SiOx) or silicon nitride (SiNx) film can be used. By this, silicon oxide (SiOx) or silicon nitride (S) is formed only on the side surface of the gate electrode 4017.
side wall 402 on the side of the gate electrode 4017 because the iNx film can be left.
One can be formed.

In the transistor 4005, a mask 4022 is formed so as to cover the gate electrode 4017, and then impurity doping is performed to be used as an LDD (Loff) region.
, A semiconductor layer 4013, and a semiconductor layer 4015 used as a source region and a drain region.
Can be formed.

In the transistor 4006, the gate electrode 4017 is formed and then impurity doping is performed to form the semiconductor layer 4013 used as an LDD (Lov) region, the semiconductor layer 4013, and the semiconductor layer 4015 used as a source region and a drain region. it can.

Next, an insulating film 4018 is formed (FIG. 48G). The insulating film 4018 is made of silicon oxide (SiOx) or silicon nitride (SiNx) by a known means (such as sputtering or plasma CVD).
, Silicon oxynitride (SiO x N y) (x> y), silicon nitride oxide (SiN x O y) (x> y)
A single layer structure of an insulating film having oxygen or nitrogen, such as oxygen, a film containing carbon such as DLC (diamond like carbon), or a laminated structure of these can be provided.

Here, a plasma treatment insulating film may be formed on the surface of the insulating film 4018 by performing plasma treatment on the surface of the insulating film 4018 to oxidize or nitride the surface of the insulating film 4018.
Note that the plasma processing insulating film is a rare gas (He, Ne, Ar, Kr, or the like) used for the plasma processing.
Containing at least one of Xe). Also, plasma processing can be performed under the conditions described above.

Next, an insulating film 4019 is formed (FIG. 48A). The insulating film 4019 is made of silicon oxide (SiOx) or silicon nitride (SiNx) by a known means (such as sputtering or plasma CVD).
, Silicon oxynitride (SiO x N y) (x> y), silicon nitride oxide (SiN x O y) (x> y)
In addition to insulating films having oxygen or nitrogen such as, or films containing carbon such as DLC (diamond like carbon), epoxy, polyimide, polyamide, polyvinyl phenol, benzocyclobutene, acrylic, etc. It can be provided with a single layer structure of an organic material or a siloxane resin, or a laminated structure of these. Note that the siloxane resin corresponds to a resin containing a Si-O-Si bond. Siloxane has a skeletal structure formed by the bond of silicon (Si) and oxygen (O). As a substituent, an organic group containing at least hydrogen (for example, an alkyl group or an aryl group) is used. A fluoro group can also be used as a substituent. Alternatively, as a substituent, an organic group containing at least hydrogen and a fluoro group may be used. Further, the plasma-treated insulating film contains a rare gas (including at least one of He, Ne, Ar, Kr, and Xe) used in plasma treatment, and, for example, plasma-treated insulating film is used when Ar is used. The film contains Ar.

In the case where an organic material such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, or acrylic, a siloxane resin, or the like is used as the insulating film 4019, the surface of the insulating film 4019 is oxidized or nitrided by plasma treatment to form the insulating film. Can be modified. By modifying the surface, it is possible to improve the strength of the insulating film 4019 and to reduce physical damage such as generation of cracks at the time of formation of the opening and film reduction at the time of etching. In addition, when the conductive film 4023 is formed over the insulating film 4019 by modifying the surface of the insulating film 4019, adhesion with the conductive film is improved. For example, when nitridation is performed using plasma treatment using a siloxane resin as the insulating film 4019, the surface of the siloxane resin is nitrided to form a plasma treatment insulating film containing nitrogen or a rare gas, and the physical strength is improved. improves.

Next, in order to form a conductive film 4023 electrically connected to the semiconductor layer 4015, the insulating film 4 is formed.
Contact holes are formed in the insulating film 4018 and the insulating film 4016. In addition, the shape of the contact hole may be tapered, and the conductive film 4 can be formed by using such a shape.
The coverage of 023 can be improved.

FIG. 49 shows a cross-sectional structure of a bottom-gate transistor and a cross-sectional structure of a capacitor.

A first insulating film (insulating film 4102) is formed over the entire surface of the substrate 4101. The first insulating film has a function of preventing impurities from the substrate side affecting the semiconductor layer to change the characteristics of the transistor. That is, the first insulating film has a function as a base film. Therefore, a highly reliable transistor can be manufactured. Note that as the first insulating film, a single layer of a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiOxNy), or the like, or a stacked layer thereof can be used.

A first conductive layer (conductive layers 4103 and 4104) is formed over the first insulating film. The conductive layer 4103 includes a portion functioning as a gate electrode of the transistor 4120.
The conductive layer 4104 includes a portion functioning as a first electrode of the capacitor 4121. Note that, as the first conductive layer, Ti, Mo, Ta, Cr, W, Al, Nd, Cu, Ag, Au, P
t, Si, Zn, Fe, Ba, Ge, etc., or alloys of these can be used. Alternatively, a stack of these elements (including an alloy) can be used.

A second insulating film (insulating film 4122) is formed to cover at least the first conductive layer. The second insulating film has a function as a gate insulating film. Note that a single layer of a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiOxNy), or the like, or a stacked layer thereof can be used as the second insulating film.

Note that a silicon oxide film is preferably used as a second insulating film in a portion in contact with the semiconductor layer. This is because the trap level at the interface where the semiconductor layer and the second insulating film are in contact decreases.

When the second insulating film is in contact with Mo, a silicon oxide film is preferably used as the second insulating film in a portion in contact with Mo. This is because the silicon oxide film does not oxidize Mo.

A semiconductor layer is formed by a photolithography method, an inkjet method, a printing method, or the like on part of a portion of the second insulating film which is formed to overlap with the first conductive layer. Then, a portion of the semiconductor layer is extended to a portion which is not formed overlapping with the first conductive layer on the second insulating film. The semiconductor layer has a channel formation region (channel formation region 4110).
, LDD regions (LDD regions 4108 and LDD regions 4109), and impurity regions (impurity regions 4105, 4106, and 4107). The channel formation region 4110 functions as a channel formation region of the transistor 4120. The LDD region 4108 and the LDD region 4109 function as an LDD region of the transistor 4120. Note that the LDD region 4108 and the LDD region 4109 are not necessarily required. The impurity region 4105 includes a portion functioning as one of a source region and a drain region of the transistor 4120. The impurity region 4106 includes a portion functioning as the other of the source region and the drain region of the transistor 4120. The impurity region 4107 includes a portion functioning as a second electrode of the capacitor 4121.

A third insulating film (insulating film 4111) is formed on the entire surface. A part of the third insulating film
Contact holes are selectively formed. The insulating film 4111 has a function as an interlayer film. As the third insulating film, an inorganic material (silicon oxide, silicon nitride, silicon oxynitride or the like) or a low dielectric constant organic compound material (photosensitive or non-photosensitive organic resin material)
Etc. can be used. Alternatively, a material containing siloxane can also be used. Siloxane is a material having a skeletal structure formed by the bond of silicon (Si) and oxygen (O). Organic group containing at least hydrogen as a substituent (eg, alkyl group, aryl group)
Is used. Alternatively, a fluoro group may be used as a substituent. Alternatively, as a substituent, an organic group containing at least hydrogen and a fluoro group may be used.

A second conductive layer (conductive layer 4112) is formed over the third insulating film. Conductive layer 4112
Is connected to the other of the source region and the drain region of the transistor 4120 through the contact hole formed in the third insulating film. Thus, the conductive layer 4112 includes a portion functioning as the other of the source electrode and the drain electrode of the transistor 4120. Note that
As the second conductive layer, Ti, Mo, Ta, Cr, W, Al, Nd, Cu, Ag, Au,
Pt, Si, Zn, Fe, Ba, Ge, etc., or alloys of these can be used. Alternatively, a stack of these elements (including an alloy) can be used.

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

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

FIG. 50 shows a cross-sectional structure of a top gate type transistor and a cross-sectional structure of a capacitor.

A first insulating film (insulating film 4202) is formed over the entire surface of the substrate 4201. The first insulating film has a function of preventing impurities from the substrate side affecting the semiconductor layer to change the properties of the transistor. That is, the first insulating film has a function as a base film. Therefore, a highly reliable transistor can be manufactured. Note that as the first insulating film, a single layer of a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiOxNy), or the like, or a stacked layer thereof can be used.

Note that the first insulating film does not necessarily have to be formed. In this case, the number of processes can be reduced. The manufacturing cost can be reduced. Since the structure can be simplified, the yield can be improved.

A first conductive layer (a conductive layer 4203, a conductive layer 4204, and a conductive layer 4205 are formed over the first insulating film.
) Is formed. The conductive layer 4203 includes a portion functioning as one of a source electrode and a drain electrode of the transistor 4220. The conductive layer 4204 includes a transistor 422.
0 includes a portion functioning as the other of the source electrode and the drain electrode. Conductive layer 420
5 includes a portion functioning as a first electrode of the capacitor 4221. Note that as the first conductive layer, Ti, Mo, Ta, Cr, W, Al, Nd, Cu, Ag, Au, Pt, Si, Z
n, Fe, Ba, Ge, etc., or alloys of these can be used. Alternatively, a stack of these elements (including an alloy) can be used.

A first semiconductor layer (a semiconductor layer 4206 and a semiconductor layer 4207) is formed over the conductive layer 4203 and the conductive layer 4204. The semiconductor layer 4206 includes a portion functioning as one electrode of the source region and the drain region. The semiconductor layer 4207 includes a portion functioning as the other of the source region and the drain region. Note that silicon or the like containing phosphorus or the like can be used as the first semiconductor layer.

A second semiconductor layer (semiconductor layer 4208) is formed between the conductive layer 4203 and the conductive layer 4204 and over the first insulating film. Then, a part of the semiconductor layer 4208 is extended to the conductive layer 4203 and the conductive layer 4204. The semiconductor layer 4208 includes a portion functioning as a channel region of the transistor 4220. As the second semiconductor layer,
A non-crystalline semiconductor layer such as amorphous silicon (a-Si: H) or a semiconductor layer such as a microcrystalline semiconductor (μ-Si: H) can be used.

The second insulating film (insulating film 4) is formed to cover at least the semiconductor layer 4208 and the conductive layer 4205.
209 and an insulating film 4210) are formed. The second insulating film has a function as a gate insulating film. Note that a single layer of a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiOxNy), or the like, or a stacked layer thereof can be used as the second insulating film.

Note that a silicon oxide film is preferably used as a second insulating film in a portion in contact with the second semiconductor layer. This is because the trap level at the interface where the second semiconductor layer and the second insulating film are in contact decreases.

When the second insulating film is in contact with Mo, a silicon oxide film is preferably used as the second insulating film in a portion in contact with Mo. This is because the silicon oxide film does not oxidize Mo.

A second conductive layer (conductive layers 4211 and 4212) is formed over the second insulating film. The conductive layer 4211 includes a portion functioning as a gate electrode of the transistor 4220.
The conductive layer 4212 has a function as a second electrode of the capacitor 4221 or a wiring. Note that, as the second conductive layer, Ti, Mo, Ta, Cr, W, Al, Nd, Cu, Ag, A
u, Pt, Si, Zn, Fe, Ba, Ge, etc., or alloys of these can be used. Alternatively, a stack of these elements (including an alloy) can be used.

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

FIG. 51 shows a cross sectional structure of a reverse staggered (bottom gate) transistor and a cross sectional structure of a capacitor. In particular, the transistor illustrated in FIG. 51 has a structure called a channel etch type.

A first insulating film (insulating film 4302) is formed over the entire surface of the substrate 4301. The first insulating film has a function of preventing impurities from the substrate side affecting the semiconductor layer to change the properties of the transistor. That is, the first insulating film has a function as a base film. Therefore, a highly reliable transistor can be manufactured. Note that as the first insulating film, a single layer of a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiOxNy), or the like, or a stacked layer thereof can be used.

Note that the first insulating film does not necessarily have to be formed. In this case, the number of processes 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 layers 4303 and 4304) is formed over the first insulating film. The conductive layer 4303 includes a portion functioning as a gate electrode of the transistor 4320.
The conductive layer 4304 includes a portion functioning as a first electrode of the capacitor 4321. Note that as the first conductive layer, Ti, Mo, TB, Cr, W, Bl, Nd, Cu, Bg, Bu, P
t, NA-Si, Zn, Fe, Ba, Ge, etc., or alloys of these can be used. Alternatively, a stack of these elements (including an alloy) can be used.

A second insulating film (insulating film 4302) is formed to cover at least the first conductive layer. The second insulating film has a function as a gate insulating film. Note that a single layer of a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiOxNy), or the like, or a stacked layer thereof can be used as the second insulating film.

Note that a silicon oxide film is preferably used as a second insulating film in a portion in contact with the semiconductor layer. This is because the trap level at the interface where the semiconductor layer and the second insulating film are in contact decreases.

When the second insulating film is in contact with Mo, a silicon oxide film is preferably used as the second insulating film in a portion in contact with Mo. This is because the silicon oxide film does not oxidize Mo.

The first semiconductor layer (semiconductor layer 43) is formed on part of the portion of the second insulating film which is formed so as to overlap with the first conductive layer by a photolithography method, an inkjet method, a printing method, or the like.
06) is formed. Then, a portion of the semiconductor layer 4306 is extended to a portion which is not formed overlapping with the first conductive layer on the second insulating film. The semiconductor layer 4306 is
A portion which functions as a channel region of the transistor 4320 is included. The semiconductor layer 430
As 6, a semiconductor layer having non-crystallinity such as amorphous silicon (A-Si: H) or a semiconductor layer such as a microcrystalline semiconductor (μ-Si: H) can be used.

A second semiconductor layer (a semiconductor layer 4307 and a semiconductor layer 4308) on a part of the first semiconductor layer
Is formed. The semiconductor layer 4307 includes a portion functioning as one electrode of the source region and the drain region. The semiconductor layer 4308 includes a portion functioning as the other of the source region and the drain region. Note that silicon or the like containing phosphorus or the like can be used as the second conductor layer.

A second conductive layer (conductive layer 4309, a conductive layer 431) is formed over the second semiconductor layer and the second insulating film.
0 and a conductive layer 4311) are formed. The conductive layer 4309 includes a portion functioning as one of a source electrode and a drain electrode of the transistor 4320. The conductive layer 4310 includes a portion functioning as the other of the source and drain electrodes of the transistor 4320. Conductive layer 431
2 includes a portion functioning as a second electrode of the capacitor 4321. Note that as the second conductive layer, Ti, Mo, Ta, Cr, W, Al, Nd, Cu, Ag, Au, Pt, Si, Z
n, Fe, Ba, Ge, etc., or alloys of these can be used. Alternatively, a stack of these elements (including an alloy) can be used.

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

Here, an example of a process characterized by a channel etch type transistor will be described. The same mask can be used to form the first semiconductor layer and the second semiconductor layer. In particular,
The first semiconductor layer and the second semiconductor layer are continuously formed. The first semiconductor layer and the second semiconductor layer are formed using the same mask.

Another example of a process characterized by a channel etch type transistor will be described. The channel region of the transistor can be formed without using a new mask. In particular,
After the second conductive layer is formed, a portion of the second semiconductor layer is removed using the second conductive layer as a mask. Alternatively, part of the second semiconductor layer is removed using the same mask as the second conductive layer. Then, a first semiconductor layer formed under the removed second semiconductor layer becomes a channel region of the transistor.

FIG. 52 shows a cross sectional structure of a reverse staggered (bottom gate) transistor and a cross sectional structure of a capacitor. In particular, the transistor illustrated in FIG. 52 has a structure called a channel protective type (channel stop type).

A first insulating film (insulating film 4402) is formed over the entire surface of the substrate 4401. The first insulating film has a function of preventing impurities from the substrate side affecting the semiconductor layer to change the properties of the transistor. That is, the first insulating film has a function as a base film. Therefore, a highly reliable transistor can be manufactured. Note that as the first insulating film, a single layer of a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiOxNy), or the like, or a stacked layer thereof can be used.

Note that the first insulating film does not necessarily have to be formed. In this case, the number of processes 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 layers 4403 and 4404) is formed over the first insulating film. The conductive layer 4403 includes a portion functioning as a gate electrode of the transistor 4420.
The conductive layer 4404 includes a portion functioning as a first electrode of the capacitor 4421. Note that, as the first conductive layer, Ti, Mo, Ta, Cr, W, Al, Nd, Cu, Ag, Au, P
t, Si, Zn, Fe, Ba, Ge, etc., or alloys of these can be used. Alternatively, a stack of these elements (including an alloy) can be used.

A second insulating film (insulating film 4402) is formed to cover at least the first conductive layer. The second insulating film has a function as a gate insulating film. Note that a single layer of a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiOxNy), or the like, or a stacked layer thereof can be used as the second insulating film.

Note that a silicon oxide film is preferably used as a second insulating film in a portion in contact with the semiconductor layer. This is because the trap level at the interface where the semiconductor layer and the second insulating film are in contact decreases.

When the second insulating film is in contact with Mo, a silicon oxide film is preferably used as the second insulating film in a portion in contact with Mo. This is because the silicon oxide film does not oxidize Mo.

The first semiconductor layer (semiconductor layer 44) is formed on part of the portion of the second insulating film which is formed so as to overlap with the first conductive layer by a photolithography method, an inkjet method, a printing method, or the like.
06) is formed. Then, a portion of the semiconductor layer 4406 is extended to a portion which is not formed overlapping with the first conductive layer on the second insulating film. The semiconductor layer 4406 is
A portion functioning as a channel region of the transistor 4420 is included. The semiconductor layer 440
As 6, a semiconductor layer having non-crystallinity such as amorphous silicon (C-Si: H) or a semiconductor layer such as a microcrystalline semiconductor (μ-Si: H) can be used.

A third insulating film (insulating film 4412) is formed on part of the first semiconductor layer. The insulating film 4412 has a function of preventing the channel region of the transistor 4420 from being removed by etching. That is, the insulating film 4412 functions as a channel protective film (channel stop film). Note that a single layer of a silicon oxide film, a silicon nitride film, a silicon oxynitride film (SiOxNy) or the like, or a stacked layer thereof can be used as the third insulating film.

A second semiconductor layer (semiconductor layer 440) is formed on a part of the first semiconductor layer and a part of the third insulating film.
And the semiconductor layer 4408) are formed. The semiconductor layer 4407 includes a portion functioning as one electrode of the source region and the drain region. The semiconductor layer 4408 includes a portion functioning as the other of the source region and the drain region. Note that silicon or the like containing phosphorus or the like can be used as the second conductor layer.

A second conductive layer (conductive layer 4409, a conductive layer 4410, and a conductive layer 441) are formed over the second semiconductor layer.
1) is formed. The conductive layer 4409 includes a portion functioning as one of a source electrode and a drain electrode of the transistor 4420. The conductive layer 4410 includes a portion which functions as the other of the source and drain electrodes of the transistor 4420. The conductive layer 4411 is a capacitor 44
And 21 includes a portion functioning as a second electrode. In addition, as the second conductive layer, Ti, Mo
, Ta, Cr, W, Al, Nd, Cu, Ag, Au, Pt, Si, Zn, Fe, Ba, G
e, etc., or alloys of these can be used. Alternatively, a stack of these elements (including an alloy) can be used.

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

Here, an example of a process which is characterized by a channel protective transistor is described. The same mask can be used to form the first semiconductor layer, the second semiconductor layer, and the second conductive layer.
At the same time, a channel region can be formed. Specifically, the first semiconductor layer is deposited,
Next, a third insulating film (channel protective film, channel stop film) is formed using a mask,
Next, the second semiconductor layer and the second conductive layer are formed successively. 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, since the first semiconductor layer under the third insulating film is protected by the third insulating film, it is not removed by etching. This portion (the portion where the third insulating film is formed on the upper portion of the first semiconductor layer) serves as a channel region.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of the present embodiment can be applied to or combined with the contents (or a part) described in the figures of other embodiments and examples. Or replacement can be freely performed. Furthermore, in the drawings of this embodiment, more drawings can be configured by combining the parts of the other embodiments and the examples with respect to the respective parts.

In this embodiment, the contents (may be a part) described in the other embodiments and examples are as follows:
An example of implementation, an example of slight modification, an example of partial modification, an example of modification, an example of detailed description, an example of application, an example of related parts And so on. Therefore, the contents described in the other embodiments and examples can be freely applied to, combined with, or replaced with this embodiment.

(Embodiment 12)
In the present embodiment, an example of an electronic device according to the present invention will be described.

FIG. 53 shows an embodiment of a display panel module in which a display panel 4501 and a circuit board 4502 are combined.

As shown in FIG. 53, the display panel 4501 includes a pixel portion 4503 and a scan line driver circuit 4504.
And a signal line driver circuit 4505. For example, a control circuit 4506, a signal division circuit 4507, and the like are formed on the circuit board 4502. Display panel 450
1 and the circuit board 4502 are connected by connection wiring 4508. For the connection wiring 4508, an FPC or the like can be used.

In the display panel 4501, a pixel portion and a part of peripheral drive circuits (drive circuits having a low operating frequency among a plurality of drive circuits) are integrally formed on a substrate using transistors, and other peripheral drive circuits (a plurality of drive circuits The driver circuit having a high operating frequency) may be formed on an IC chip, and the IC chip may be mounted on the display panel 3410 by COG (Chip On Glass). Alternatively, the IC chip may be connected to the glass substrate using TAB (Tape Auto Bonding) or a printed substrate. Alternatively, all the peripheral drive circuits may be formed on an IC chip, and the IC chip may be mounted on a display panel by COG or the like.

Note that the pixel described in the above embodiment is used for the pixel portion. According to the present invention, the viewing angle can be improved. In addition, cost reduction can also be achieved by using an amorphous semiconductor for a semiconductor layer of a transistor having the same conductivity type or a transistor in a pixel portion.

Such a display module can complete a television receiver. Figure 54
It is a block diagram which shows the main structures of a television receiver. The tuner 4601 receives a video signal and an audio signal. The video signal includes a video signal amplifier circuit 4602, a video signal processing circuit 4603 which converts the signal output from the video signal into a color signal corresponding to each color of red, green and blue, and the video signal as an input specification of the drive circuit. It is processed by the control circuit 4506 for conversion.
The control circuit 4506 outputs signals to the scanning line side and the signal line side, respectively. In the case of digital driving, a signal dividing circuit 4507 is provided on the signal line side, and m input digital signals (m
m may be divided into positive integers) and supplied.

Among the signals received by the tuner 4601, an audio signal is sent to an audio signal amplifier circuit 4604, and an output thereof is supplied to a speaker 4606 through an audio signal processing circuit 4605. A control circuit 4607 receives control information of a receiving station (reception frequency) and volume from an input unit 4608, and sends a signal to a tuner 4601 and an audio signal processing circuit 4605.

A television receiver incorporating a display panel module having a form different from that of FIG.
Shown in A). In FIG. 55A, a display screen 4702 housed in a housing 4701 is
It is formed of a display panel module. The speaker 4703 and the operation switch 4704
And the like may be provided as appropriate.

FIG. 55 (B) shows a television receiver in which only a display can be carried wirelessly.
A battery and a signal receiver are incorporated in the housing 4712, and the display portion 4713 or the speaker portion 4717 is driven by the battery. The battery can be repeatedly charged by the charger 4710. The charger 4710 can transmit and receive video signals, and can transmit the video signals to a signal receiver of the display. The housing 4712 is controlled by the operation key 4716. Alternatively, the device illustrated in FIG. 55B may be a video / audio two-way communication device which can send a signal from the housing 4712 to the charger 4710 by operating the operation key 4716. Alternatively, by operating the operation key 4716, a signal is sent from the housing 4712 to the charger 4710, and by causing another electronic device to receive a signal that can be transmitted by the charger 4710, communication control of the other electronic devices is also performed. It may also be a universal remote control. The present invention can be applied to the display portion 4713.

FIG. 56A shows a module in which the display panel 4801 and the printed wiring board 4802 are combined. The display panel 4801 includes a pixel portion 4803 in which a plurality of pixels are provided,
A first scan line driver circuit 4804, a second scan line driver circuit 4805, and a signal line driver circuit 4806 which supplies a video signal to a selected pixel are included.

The printed wiring board 4802 includes a controller 4807 and a central processing unit (CPU) 480.
8. Memory 4809, power supply circuit 4810, audio processing circuit 4811, and transmission / reception circuit 4812
Etc are provided. The printed wiring board 4802 and the display panel 4801 are connected by a flexible wiring board (FPC) 4813. Flexible Wiring Board (FPC)
In the 4813, a storage capacitor, a buffer circuit, and the like are provided to generate noise in the power supply voltage or the signal,
And it is good also as composition which prevents increase of rise time of a signal. The controller 4807
, The voice processing circuit 4811, the memory 4809, the central processing unit (CPU) 4808, the power supply circuit 4810, and the like use a display panel 480 using a COG (Chip On Glass) method.
It can also be implemented in 1. By the COG method, the size of the printed wiring board 4802 can be reduced.

Various control signals are input / output via an interface (I / F) unit 4814 provided on the printed wiring board 4802. Then, an antenna port 4815 for transmitting and receiving signals to and from the antenna is provided on the printed wiring board 4802.

FIG. 56 (B) shows a block diagram of the module shown in FIG. 56 (A). This module includes the VRAM 4816, the DRAM 4817, and the flash memory 48 as the memory 4809.
18 etc. are included. The image data to be displayed on the panel is DR
Image data or audio data is stored in the AM 4817, and various programs are stored in the flash memory.

The power supply circuit 4810 includes a display panel 4801, a controller 4807, and a central processing unit (CP).
U) Power for operating the 4808, the audio processing circuit 4811, the memory 4809, and the transmitting and receiving circuit 4812 is supplied. However, depending on the specification of the panel, the power supply circuit 4810 may be provided with a current source.

A central processing unit (CPU) 4808 includes a control signal generation circuit 4820, a decoder 4821, a register 4822, an arithmetic circuit 4823, a RAM 4824, and a central processing unit (CPU) 4808.
Interface (I / F) unit 4819 and the like. Interface (I /
F) Various signals input to the central processing unit (CPU) 4808 through the unit 4819 are temporarily stored in the register 4822 and then input to the arithmetic circuit 4823, the decoder 4821, and the like. The arithmetic circuit 4823 carries out an operation based on the input signal, and designates a place to which various instructions are sent. On the other hand, the signal input to the decoder 4821 is decoded, and the control signal generation circuit 4 is
It is input to 820. Control signal generation circuit 4820 generates a signal including various instructions based on the input signal, and a location designated by operation circuit 4823, specifically, memory 480.
9. Send to the transmission / reception circuit 4812, the audio processing circuit 4811, the controller 4807, and the like.

The memory 4809, the transmission / reception circuit 4812, the audio processing circuit 4811, and the controller 4807 operate in accordance with the received instructions. The operation will be briefly described below.

A signal input from the input unit 4825 is sent to a central processing unit (CPU) 4808 mounted on a printed wiring board 4802 via an interface (I / F) unit 4814.
The control signal generation circuit 4820 is an input unit 4 such as a pointing device or a keyboard.
According to the signal sent from 825, the image data stored in the VRAM 4816 is converted into a predetermined format and sent to the controller 4807.

The controller 4807 performs data processing on the signal including the image data sent from the central processing unit (CPU) 4808 in accordance with the specification of the panel, and supplies the processed signal to the display panel 4801. The controller 4807 is a Hsync signal, a Vsync signal, a clock signal CLK, an AC voltage (AC Cont), based on the power supply voltage input from the power supply circuit 4810 or various signals input from the central processing unit (CPU) 4808. Generate switching signal L / R,
The display panel 4801 is supplied.

In the transmission / reception circuit 4812, a signal transmitted / received as a radio wave is processed in the antenna 4828, and specifically, an isolator, a band pass filter, a VCO (Voltage
Controlled Oscillator), LPF (Low Pass Filt)
er), couplers, baluns, and other high frequency circuits may be included. Among the signals transmitted and received by the transmission / reception circuit 4812, a signal including audio information is sent to the audio processing circuit 4811 in accordance with an instruction from the central processing unit (CPU) 4808.

A signal including audio information sent in accordance with an instruction of the central processing unit (CPU) 4808 is demodulated into an audio signal in an audio processing circuit 4811 and sent to a speaker 4827. The audio signal sent from the microphone 4826 is modulated in the audio processing circuit 4811 and sent to the transmission / reception circuit 4812 in accordance with an instruction from the central processing unit (CPU) 4808.

The controller 4807, the central processing unit (CPU) 4808, the power supply circuit 4810, the audio processing circuit 4811, and the memory 4809 can be mounted as a package of this embodiment.

Of course, the present embodiment is not limited to a television receiver, and is used as a display medium for a personal computer, an information display board at a railway station or airport, an advertisement display board at a street, etc. It can apply.

Next, referring to FIG. 57, a configuration example of a mobile phone according to the present invention will be described.

The display panel 4901 is detachably incorporated into the housing 4930. Housing 493
The shape or size of 0 can be changed as appropriate in accordance with the size of the display panel 4901. A housing 4930 to which the display panel 4901 is fixed is fitted into a printed circuit board 4931 and assembled as a module.

The display panel 4901 is connected to the printed circuit board 4931 through the FPC 4913. The printed circuit board 4931 includes a speaker 4932, a microphone 4933, and a transmission / reception circuit 49.
34, a signal processing circuit 4935 including a CPU, a controller and the like is formed. Such a module is combined with an input unit 4936 and a battery 4937 to obtain a housing 493.
Store in 9 A pixel portion of the display panel 4901 is arranged so as to be visible from an opening window formed in the housing 4939.

In the display panel 4901, a pixel portion and a part of peripheral drive circuits (a drive circuit having a low operating frequency among a plurality of drive circuits) are integrally formed on a substrate using transistors, and a part of peripheral drive circuits (a plurality of drive circuits). Among the circuits, a driver circuit having a high operating frequency may be formed over an IC chip, and the IC chip may be mounted on the display panel 4901 by COG (Chip On Glass). Alternatively, the IC chip may be connected to the glass substrate using TAB (Tape Auto Bonding) or a printed circuit board. With such a configuration, power consumption of the display device can be reduced, and the usage time per charge of the mobile phone can be extended. Cost reduction of the mobile phone can be achieved.

The mobile phone shown in FIG. 57 has a function of displaying various information (still images, moving images, text images, etc.). It has a function of displaying a calendar, date or time on a display unit. It has a function of operating or editing the information displayed on the display unit. It has a function to control processing by various software (programs). It has a wireless communication function. The wireless communication function is used to make a call to another mobile phone, fixed telephone or voice communication device. It has a function of connecting to various computer networks using a wireless communication function. The wireless communication function is used to transmit or receive various data. The vibrator has a function of operating in response to an incoming call, data reception, or an alarm. It has a function of generating a sound in response to an incoming call, data reception, or an alarm. In addition, the function which the mobile telephone shown in FIG. 57 has is not limited to this,
It can have various functions.

The mobile phone shown in FIG. 58 includes a main body (A) 5001 including operation switches 5004 and a microphone 5005, a display panel (A) 5008, and a display panel (B) 5009.
, And a main body (B) 5002 provided with a speaker 5006 and the like are connected to be openable and closable by a hinge 5010. The display panel (A) 5008 and the display panel (B) 5009 are housed in a housing 5003 of the main body (B) 5002 together with the circuit board 5007. Display panel (A
The pixel portion of the display panel (B) 5008 and the display panel (B) 5009 is disposed so as to be visible from an opening window formed in the housing 5003.

The display panel (A) 5008 and the display panel (B) 5009 can appropriately set specifications such as the number of pixels in accordance with the function of the mobile phone 5000. For example, display panel (A) 5
It is possible to combine the display panel (B) 5009 as a sub screen, with the 008 as a main screen.

The mobile phone according to the present embodiment can be changed into various modes according to the function or application. For example, an imaging device may be incorporated in the region of the hinge 5010 to provide a mobile phone with a camera. Operation switches 5004, display panel (A) 5008, display panel (B) 500
Even in the configuration in which 9 is contained in one case, the above-described effects can be obtained. Even if the configuration of the present embodiment is applied to an information display terminal provided with a plurality of display units, similar effects can be obtained.

The mobile phone shown in FIG. 58 has a function of displaying various information (still images, moving images, text images, and the like). It has a function of displaying a calendar, date or time on a display unit. It has a function of operating or editing the information displayed on the display unit. It has a function to control processing by various software (programs). It has a wireless communication function. The wireless communication function is used to make a call to another mobile phone, fixed telephone or voice communication device. It has a function of connecting to various computer networks using a wireless communication function. The wireless communication function is used to transmit or receive various data. The vibrator has a function of operating in response to an incoming call, data reception, or an alarm. It has a function of generating a sound in response to an incoming call, data reception, or an alarm. In addition, the function which the mobile telephone shown in FIG. 58 has is not limited to this,
It can have various functions.

The present invention can be applied to various electronic devices. Specifically, the present invention can be applied to a display portion of an electronic device. As such electronic devices, video cameras, digital cameras, goggle type displays, navigation systems, sound reproduction devices (car audios, audio components, etc.), computers, game machines, portable information terminals (mobile computers, mobile phones, portable games, etc.) Machine or electronic book, etc.), an image reproduction apparatus (specifically, D
An apparatus provided with a display capable of reproducing a recording medium such as a digital versatile disc (DVD) and displaying the image.

FIG. 59A shows a display, which includes a housing 5111, a support 5112, a display portion 5113, and the like. The display shown in FIG. 59A has a function of displaying various information (a still image, a moving image, a text image, and the like) on the display portion. Note that the function of the display illustrated in FIG. 59A is not limited to this, and can have various functions.

FIG. 59B shows a camera, which includes a main body 5121, a display portion 5122, an image receiving portion 5123, an operation key 5124, an external connection port 5125, a shutter button 5126, and the like. Figure 59 (B
The camera shown in) has a function of capturing a still image. It has a function to shoot video. It has a function to automatically correct a captured image (still image, moving image). It has a function of storing a captured image in a recording medium (external or internal to a digital camera). It has a function of displaying a photographed image on a display unit. Note that the camera in FIG. 59B can have various functions without limitation to the above.

FIG. 59C shows a computer, which includes a main body 5131, a housing 5132, a display portion 5133, a keyboard 5134, an external connection port 5135, a pointing device 5136, and the like. The computer illustrated in FIG. 59C includes various information (still images, moving images, text images, and the like).
Is displayed on the display unit. It has a function to control processing by various software (programs). It has a communication function such as wireless communication or wired communication. It has a function of connecting to various computer networks using a communication function. It has a function of transmitting and receiving various data using a communication function. Note that functions of the computer illustrated in FIG. 59C are not limited to this, and can have various functions.

FIG. 59D shows a mobile computer, which includes a main body 5141, a display portion 5142, a switch 5143, operation keys 5144, an infrared port 5145, and the like. The mobile computer illustrated in FIG. 59D has a function of displaying various information (still image, moving image, text image, and the like) on the display portion. The display unit has a touch panel function. The display unit has a function of displaying a calendar, date, time, and the like. It has a function to control processing by various software (programs). It has a wireless communication function. It has a function of connecting to various computer networks using a wireless communication function. The wireless communication function is used to transmit or receive various data. Note that the functions of the mobile computer illustrated in FIG. 59D are not limited to this, and can have various functions.

FIG. 59E shows a portable image reproducing apparatus (for example, a DVD reproducing apparatus) including a recording medium, which includes a main body 5151, a housing 5152, a display portion A5153, a display portion B5154, a recording medium
DVD etc.) including a reading unit 5155, operation keys 5156, a speaker unit 5157 and the like. The display portion A 5153 can mainly display image information, and the display portion B 5154 can mainly display text information.

FIG. 59F shows a goggle type display, which includes a main body 5161, a display portion 5162, an earphone 5163, and a support portion 5164. The goggle type display shown in FIG. 59F has a function of displaying an image (a still image, a moving image, a text image, or the like) acquired from the outside on a display portion. The goggle type display shown in FIG. 59F has a variety of functions without limitation to the above.

FIG. 59G shows a portable game machine, which includes a housing 5171, a display portion 5172, and a speaker portion 51.
And 73, an operation key 5174, a storage medium insertion portion 5175 and the like. A portable game machine using the display device of the present invention for the display portion 5172 can express bright colors. Figure 59 (G)
The portable game machine shown in has a function of reading out the program or data recorded in the recording medium and displaying it on the display portion. It has a function of performing wireless communication with another portable game machine to share information. Note that the portable game machine illustrated in FIG. 59G can have various functions without limitation to the above.

FIG. 59H shows a digital camera with a television receiver function, and a main body 5181 and a display portion 518.
2, operation key 5183, speaker 5184, shutter button 5185, image receiving unit 518
6, including the antenna 5187 and the like. The digital camera with a television receiver shown in FIG. 59H has a function of capturing a still image. It has a function to shoot video. It has a function to automatically correct the captured image. It has a function of acquiring various information from the antenna. It has a function of storing a photographed image or information acquired from an antenna. It has a function of displaying a photographed image or information acquired from an antenna on a display portion. Note that the digital camera with a television receiver shown in FIG. 59H has a variety of functions without limitation to the above.

As shown in FIGS. 59A to 59E, the electronic device according to the present invention is characterized by having a display portion for displaying some information. Since the electronic device according to the present invention can reduce the operation frequency of the circuit by storing the data in the memory when the data is duplicated, the power consumption is small and the battery can be driven for a long time. is there.
Next, application examples of the display device according to the present invention will be described.

FIG. 60 shows an example in which the display device according to the present invention is provided integrally with a building. Figure 60.
Shows a structure including a housing 5200, a display panel 5201, a speaker portion 5202 and the like. Reference numeral 5203 denotes a remote control device for operating the display panel 5201.

The pixel described in the above embodiment is used for the display panel 5201. According to the present invention, it is possible to obtain a display panel with high display quality which is excellent in viewing angle characteristics. In addition, cost reduction can also be achieved by using an amorphous semiconductor for a semiconductor layer of a transistor having the same conductivity type or a transistor in a pixel portion.

Since the display device shown in FIG. 60 is provided integrally with the structure, it can be installed without requiring a large space.

FIG. 61 shows another example in which the display device according to the present invention is integrated with a building. The display panel 5301 is attached integrally with the unit bus 5302, and a bather can view the display panel 5301 while taking a bath. Information can be displayed on the display panel 5301 by a bather's operation. Therefore, it has a function that can be used as advertising and entertainment means.

The pixel described in the above embodiment is used for the display panel 5301. According to the present invention, it is possible to obtain a display panel with high display quality which is excellent in viewing angle characteristics. In addition, cost reduction can also be achieved by using an amorphous semiconductor for a semiconductor layer of a transistor having the same conductivity type or a transistor in a pixel portion.

Note that the display device according to the present invention can be provided integrally with various places in addition to the side wall of the unit bus 5302 shown in FIG. For example, it may be provided integrally with part of the mirror surface or the bathtub itself. Further, the shape of the display device may be matched to the shape of a mirror surface or a bathtub.

FIG. 62 shows another example in which the display device according to the present invention is provided integrally with a building.
In FIG. 62, the display panel 5402 is curved in accordance with the curved surface of the columnar body 5401. Here, the columnar body 5401 will be described as a utility pole.

The display panel 5402 shown in FIG. 62 is provided at a position higher than the human viewpoint. Information can be provided to an unspecified number of viewers through the display panel 5402 by installing the display panel 5402 on a structure which is repeatedly forested outdoors like a telephone pole. Therefore, it is suitable to use the display panel as an advertisement. In addition, since the display panel 5402 can easily display the same image by external control and can switch images instantaneously, extremely efficient information display and advertising effects can be expected. In addition, the display panel 5
By providing the self-luminous display element in 402, it can be said that it is useful as a display medium with high visibility even at night. In addition, by installing the display panel 5402 on the telephone pole, the display panel 5 is
It is easy to secure the power supply means 402. In the event of an emergency such as a disaster,
It can also be a means to quickly and accurately communicate information to victims.

The pixel described in the above embodiment is used for the display panel 5402. According to the present invention, it is possible to obtain a display panel with high display quality which is excellent in viewing angle characteristics. In addition, cost reduction can also be achieved by using an amorphous semiconductor for a semiconductor layer of a transistor having the same conductivity type or a transistor in a pixel portion. Alternatively, an organic transistor provided on a film-like substrate may be used.

In the present embodiment, a wall, a unit bus, or the like as a structure integrated with the display device of the present invention.
Although a columnar body is illustrated, it is possible to provide in other various structures.

  Next, an example in which the display device according to the present invention is provided integrally with a moving object will be described.

FIG. 63 is a view showing an example in which the display device according to the present invention is provided integrally with a car. The display panel 5502 is provided integrally with a car body 5501 of a car, and can display on-demand operation of the car body and information input from inside and outside of the car body. In addition, the display panel 5502 may have a navigation function.

The pixel described in the above embodiment is used for the display panel 5502. According to the present invention, it is possible to obtain a display panel with high display quality which is excellent in viewing angle characteristics. In addition, cost reduction can also be achieved by using an amorphous semiconductor for a semiconductor layer of a transistor having the same conductivity type or a transistor in a pixel portion.

Note that the display device according to the present invention can be provided not only in the vehicle body 5501 shown in FIG. 63 but also in various places. For example, it may be provided integrally with a glass window, a door, a handle, a shift lever, a seat, a rearview mirror and the like. At this time, the shape of the display panel 5502 may be in accordance with the shape of the object to be installed.

FIG. 64 is a view showing an example in which the display device according to the present invention is integrated with a train car.

FIG. 64 (a) is a diagram showing an example in which a display panel 5602 is provided on the glass of the door 5601 of a train car. Compared with the conventional paper advertisement, there is an advantage that the labor cost required at the time of advertisement switching is not incurred. In addition, since the display panel 5602 can instantaneously switch the image displayed on the display portion by a signal from the outside, for example, the image of the display panel can be displayed at each time zone when the passenger layer of train passengers It can be switched.
By switching images in this way, more effective advertising effects can be expected.

FIG. 64 (b) is a view showing an example in which a display panel 5602 is provided on a glass window 5603 and a ceiling 5604 in addition to the glass of the door 5601 of the train car. As described above, since the display device according to the present invention can be easily provided in a place where the installation has been difficult conventionally, an effective advertising effect can be obtained. Further, the display device according to the present invention can instantaneously switch the image displayed on the display unit by the signal from the outside, which can reduce the cost and time generated at the time of the advertisement switching, and is more flexible. Management and communication of information.

Note that the pixel described in the above embodiment is used for the display panel 5602 illustrated in FIG. According to the present invention, it is possible to obtain a display panel with high display quality which is excellent in viewing angle characteristics. In addition, cost reduction can also be achieved by using an amorphous semiconductor for a semiconductor layer of a transistor having the same conductivity type or a transistor in a pixel portion.

Further, the display device according to the present invention is not limited to the above, and can be provided in various places. For example, a strap, a seat, a bench, a floor and the like may be integrated with the display device according to the present invention. At this time, the shape of the display panel 5602 may be adjusted to the shape of the object to be installed.

FIG. 65 is a view showing an example in which the display device according to the present invention is provided integrally with a passenger plane.

FIG. 65 (a) is a view showing a shape in use when a display panel 5702 is provided on a ceiling 5701 at the top of a seat of a passenger plane. The display panel 5702 has a hinge portion 570
3 and is integrated with the ceiling 5701, and expansion and contraction of the hinge portion 5703 enables the passenger to view the display panel 5702 at a desired position. The display panel 5702 can display information when operated by a passenger. Therefore, it has a function that can be used as advertising and entertainment means. Also, as shown in FIG. 65 (b), the hinge portion is bent to make a ceiling 570.
By storing in 1, consideration can be given to safety during takeoff and landing. Note that by lighting the display elements of the display panel 5702 in an emergency, it can also be used as an information transmission means and a guide light.

Note that the pixel described in the above embodiment is used for the display panel 5702 shown in FIG. According to the present invention, it is possible to obtain a display panel with high display quality which is excellent in viewing angle characteristics. In addition, cost reduction can also be achieved by using an amorphous semiconductor for a semiconductor layer of a transistor having the same conductivity type or a transistor in a pixel portion.

Note that the display device according to the present invention can be provided integrally with various places as well as the ceiling 5701 shown in FIG. For example, it may be provided integrally with a seat, a seat table, an armrest, a window or the like. Also, a large display panel that many people can view simultaneously may be installed on the wall of the machine. At this time, the shape of the display panel 5702 may be adjusted to the shape of what is provided.

In the present embodiment, the moving body is exemplified by a train car body, an automobile body, and an airplane body, but the invention is not limited thereto, and motorcycles, four-wheeled vehicles (including cars, buses, etc.)
Various things such as trains (including monorails, trains, etc.), ships, etc. can be applied. The display device according to the present invention is capable of instantaneously switching the display of the display panel in the moving object by a signal from the outside, so that the moving object is not installed by installing the display device according to the present invention on the moving object. It can be used for applications such as advertisement display boards for a large number of specific customers, and information display boards in the event of a disaster.

Note that although the present embodiment has been described using various figures, the contents described in each figure (
Some parts may be applied to, or combined with, the contents described in another figure (or some parts).
Or, replacement can be freely performed. Furthermore, in the figures described above, more figures can be constructed by combining other parts with respect to each part.

Similarly, the contents (or a part) described in each figure of the present embodiment can be applied to or combined with the contents (or a part) described in the figures of other embodiments and examples. Or replacement can be freely performed. Furthermore, in the drawings of this embodiment, more drawings can be configured by combining the parts of the other embodiments and the examples with respect to the respective parts.

In this embodiment, the contents (may be a part) described in the other embodiments and examples are as follows:
An example of implementation, an example of slight modification, an example of partial modification, an example of modification, an example of detailed description, an example of application, an example of related parts And so on. Therefore, the contents described in the other embodiments and examples can be freely applied to, combined with, or replaced with this embodiment.

11 node 30 TFT
3a scanning line 6a data line (signal line)
100 wiring 111 switch 112 switch 113 switch 114 first resistor 115 second resistor 116 signal line 117 scanning line 118 common electrode 119 Cs line 121 first liquid crystal element 122 second liquid crystal element 131 first holding capacity 132 first 2 storage capacitor 141 node 142 node 211 first transistor 212 second transistor 213 third transistor 313 third transistor 414 transistor 511 signal line drive circuit 512 scan line drive circuit 513 pixel portion 514 pixel 614 transistor 800 node 801 Unit 814 Transistor 823 Liquid crystal element 833 Holding capacitance 116a Signal line 117a Scan line 119a Cs line 1200 Pixel 1219 Potential supply line 1300 Signal line switching circuit 1316 Wiring 1319 Wiring 1400 Unit 1401 inverter 1402 wiring 1402 wiring 1403 wiring 1404 transistor 1405 transistor 1406 transistor 1407 transistor 1430 wiring 1601 third storage capacitance 1701 third storage capacitance 1801 third storage capacitance 1802 node 1803 node 1803 transistor 1801 storage capacitance 1902 node 900 a sub Pixel 900 b sub-pixel 1000 a sub-pixel 1000 b sub-pixel 1100 a sub-pixel 1100 b sub-pixel

Claims (1)

A pixel including a first switch, a second switch, a third switch, a first resistor, a second resistor, a first liquid crystal element, and a second liquid crystal element;
Each of the first liquid crystal element and the second liquid crystal element includes at least a pixel electrode, a common electrode, and a liquid crystal controlled by the pixel electrode and the common electrode.
The pixel electrode of the first liquid crystal element is electrically connected to a first wiring through the first switch,
The pixel electrode of the first liquid crystal element is electrically connected to the pixel electrode of the second liquid crystal element through the second switch and the first resistor.
A pixel electrode of the second liquid crystal element is electrically connected to a second wiring through the third switch and the second resistor.

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