JPH0758424B2 - Matrix type display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a matrix type display device configured to control the supply of electric power to each display electrode and each scanning electrode by transmitting a signal such as light. Regarding

(Prior Art) A liquid crystal display device is often used as an image display device. However, it is necessary to create a display device having a large screen with a single panel from the viewpoint of flatness and parallelism of a pair of substrates constituting the panel. difficult.

Further, there is a limit to the increase in the number of scanning electrodes due to the crosstalk effect peculiar to the liquid crystal display device.

On the other hand, particularly in the active matrix type liquid crystal display device, the yield of the active elements sharply decreases when the screen size is increased, so that the size of one screen is limited.

Therefore, in a large-screen display device, in general, a plurality of divided liquid crystal display blocks are arranged vertically and horizontally, and each is electrically connected to form a large-screen display device.

In this case, a method has been adopted in which all the scan electrodes and the display electrodes forming a matrix between the liquid crystal display blocks are electrically connected to each other vertically or horizontally via wires.

FIG. 4 is a schematic sectional view of a liquid crystal display block of a conventional liquid crystal display device. The case of a simple matrix type liquid crystal is shown.

A plurality of strip-shaped transparent scan electrodes 2a and display electrodes 2b are provided so as to be insulated from each other and to intersect in a matrix on the respective facing sides of the substrates 1a and 1b that face each other in parallel at equal intervals. Alignment films 3a, 3 are formed on the scan electrodes 2a and the display electrodes 2b.
b are provided respectively.

The liquid crystal substance 4 is injected between the substrates 1a and 1b provided with the electrodes 2a and 2b and the alignment films 3a and 3b, respectively, and the sealing material 5
It is sealed with. Further, polarizing plates 6a and 6b are arranged on the non-opposing sides of the substrates 1a and 1b, respectively.

In the case of such a simple matrix type liquid crystal display device,
A pixel is formed at a portion where a plurality of strip-shaped scan electrodes 2a and display electrodes 2b intersect with each other.

In order to supply signals to the scanning electrodes 2a and the display electrodes 2b, it is common to extend the display electrodes and the scanning electrodes on the outer peripheral portion of the substrate and connect the lead wires to each electrode tangentially. It was

As described above, in the conventional matrix type display device, as the number of pixels increases, the structure of the scan electrodes and the display electrodes becomes complicated, and the number of wires to connect to these electrodes for supplying signals from the outside is reduced. Since the number increases, the manufacturing process is complicated, and there is a problem that defects are likely to occur at connection points.

Furthermore, when a large screen is constructed by arranging a plurality of such liquid crystal display blocks in a mosaic pattern, the scanning electrodes and display electrodes of adjacent liquid crystal display blocks must be electrically connected, and fine processing is tried. Even if it does, a minimum of 2 to 3 mm is required as a space required for electrical connection, and the band-shaped space formed on the screen of each display device cannot display.

Therefore, an undisplayable band-like void is formed as shown by the shaded area in FIG. 5, and the display is extremely difficult to see as if the image was projected on the shoji screen, and the optical aperture ratio is extremely reduced. Then there was a problem.

In order to solve the above-mentioned problems of the conventional liquid crystal display device, the present applicants have proposed Japanese Patent Application No. 62-152460 and Japanese Patent Application No.
In No. 62-152461, it is necessary to electrically connect up and down or left and right between each liquid crystal display block by transmitting information from the back side which electrode is selected by an optical signal and controlling an optical switch element. There is only a power supply line for scanning and display, there are very few wires to connect, the manufacturing process is simple, and the reliability of connection and the optical aperture ratio are greatly improved. Proposed.

FIG. 6 is an exploded perspective view schematically showing the structure of the liquid crystal display and block in Japanese Patent Application No. 62-152461.

A plurality of strip-shaped transparent scan electrodes 2a and display electrodes 2b are provided so as to be insulated from each other and to intersect in a matrix on the respective facing sides of the substrates 1a and 1b that face each other in parallel at equal intervals. Although not shown, alignment films 3a and 3b are provided on the scan electrodes 2a and the display electrodes 2b, respectively.

The liquid crystal substance 4 is injected between the substrates 1a and 1b provided with the electrodes 2a and 2b and the alignment films 3a and 3b, respectively, and the sealing material 5
It is sealed with. Further, although not shown, deflecting plates 6a and 6b are respectively arranged on the non-opposing sides of the substrates 1a and 1b.

In the case of such a simple matrix type liquid crystal display block, a pixel is formed at a portion where a plurality of strip-shaped scanning electrodes 2a and display electrodes 2b intersect each other.

On the substrate 1a, the light receiving element 7a is provided inside the seal portion 15 in FIG. 6 corresponding to the sealing material 5 in FIG.
A decoder 8a for demodulating the output signal of 7a, a distribution line 9a for distributing the output signal of the decoder 8a, and a switch circuit 10a controlled by a signal supplied by the distribution line 9a are formed.

Next, all the scan electrodes 2a are connected to the scan bus 11a for supplying power to the scan electrodes via the switch circuits 10a, respectively. The scanning bus bar 11a extends to the corner of the substrate 1a and is connected to the lead terminal 12a.

Further, on the substrate 1b, similarly, a light receiving element 7b is provided inside the seal portion, and a decoder for demodulating an output signal of the light receiving element 7b.
8b, a distribution line 9b for distributing the output signal of the decoder 8b, and a switch circuit 10b controlled by a signal supplied by the distribution line 9b are formed.

The display electrodes 2b are also connected to the display busbars 11b for supplying power to the display electrodes via the switch circuits 10b. The display bus bar 11b extends to one corner of the substrate 1b and is connected to the lead terminal 12b.

On the other hand, at the facing positions of the light receiving elements 7a and 7b, issuing elements 13a and 13b respectively corresponding to the light receiving elements 7a and 7b are arranged on the substrate 14 which faces the substrate 1a.

Next, the operation will be described. The power supply voltage is supplied to the scan bus 11a via the terminal 12a, and the power supply voltage is sequentially supplied to the scan electrodes 2a by sequentially switching on the switch circuits 10a connected thereto. The control of the switch circuit 10a will be described.

The issuing element 13a transmits, to the light receiving element 7a by light, information on which scan electrode 2a is to be supplied with the power supply voltage is encoded with a plurality of bits, for example. The light receiving element 7a receives this optical signal, converts it into an electric signal, and supplies it to the decoder 8a.

The decoder 8a demodulates (decodes) information indicating which electrode is selected, and outputs the desired switch circuit 10a via the distribution line 9a.
Is controlled to open and close, and the power supply voltage is supplied to a desired electrode.

Similarly, the light emitting element 13b transmits information to the display electrode 2b to which the power supply voltage is supplied, for example, by encoding a plurality of bits and transmitting the information to the light receiving element 7b by light. The light receiving element 7b receives this optical signal, converts it into an electric signal, and supplies it to the decoder 8b.

The decoder 8b demodulates (decodes) information about which electrode is selected, and outputs the desired switch circuit 10b via the distribution line 9b.
Is controlled to open and close, and the power supply voltage is supplied to a desired electrode.

Here, when the light emitting elements 13a, 13b are appropriately selected to emit light, the light receiving elements 7a, 13b corresponding to the respective light emitting elements 13a, 13b,
7b receives this optical signal, converts it into an electric signal, and supplies it to the decoders 8a and 8b.

The decoders 8a and 8b demodulate (decode) information regarding which electrode is selected, open / close control the desired switch circuits 10a and 10b through the distribution lines 9a and 9b, and scan the desired scanning electrode 2a from the scanning bus line 11a. Further, the power supply voltage can be applied from the display bus bar 11b to the desired display electrode 2b, and an image can be appropriately displayed.

When a plurality of liquid crystal display blocks having such a configuration are arranged in a mosaic to form a large screen, only the scanning bus bar 11a and the display bus bar 11b are electrically connected to the adjacent liquid crystal display blocks for each liquid crystal display block. Just connect. Actually, the lead terminals 12a provided at the four corners of each liquid crystal display block,
Using 12b, adjacent liquid crystal display blocks are connected to each other using wires or metal solder. Therefore, a large-screen matrix type liquid crystal display device which is relatively easy to manufacture and has extremely high reliability can be realized.

(Problems to be Solved by the Invention) However, in the conventional liquid crystal display block shown in FIG. 6, distribution wirings 9a and 9b for supplying control signals from the decoders 8a and 8b to the switch circuits 10a and 10b are provided. Only the number of electrodes required.

Due to the demand for higher resolution of the displayed image, the number of electrodes tends to increase more and more, and the distribution wiring inevitably increases.

In the peripheral portion of the substrate where these distribution lines intensively pass, there is a problem in that it becomes a multi-line wiring, which takes up a very large space, forms band gaps that cannot be displayed, and lowers the optical aperture ratio.

The present invention has been made paying attention to the above points, converts a signal received by a light receiving element or the like into an electric signal, and supplies the same signal to each decoder / switch by one line,
By demodulating the information about which electrode is selected here, the power supply voltage can be supplied to the desired electrode, and a large number of distribution lines are not required, and the optical aperture ratio of the screen can be improved. An object of the present invention is to provide a matrix type display device.

(Means for Solving the Problem) In order to solve the above-mentioned problems, the present invention provides a pair of parallel-opposed scan electrodes and display electrodes that are insulated from each other and cross each other in a matrix. In a matrix type display device in which a plurality of liquid crystal display blocks each having a substrate are arranged on the upper, lower, left and right sides, a transmitting element for transmitting information on which electrode is selected from the plurality of scanning electrodes and display electrodes, and a transmitting element from the transmitting element. Receiving device and a plurality of decoders that are supplied with the output signal of the receiving device and demodulate information about which electrode is selected to drive the corresponding electrodes, if applicable. Provided is a matrix type display device having a liquid crystal display block composed of a switch, wherein the plurality of decoder switches are composed of individual parts. It is a thing.

(Embodiment) FIG. 1 is an exploded perspective view schematically showing an embodiment of a liquid crystal display block in a matrix type display device of the present invention.

In FIG. 1, the same parts as those in FIG. 6 are designated by the same reference numerals. A plurality of strip-shaped transparent scan electrodes 2a and display electrodes 2b are provided so as to be insulated from each other and to intersect in a matrix on the respective facing sides of the substrates 1a and 1b that face each other in parallel at equal intervals. Although not shown, alignment films 3a and 3b are provided on the scan electrodes 2a and the display electrodes 2b, respectively.

The liquid crystal substance 4 is injected between the substrates 1a and 1b provided with the electrodes 2a and 2b and the alignment films 3a and 3b, respectively, and the sealing material 5
It is sealed with. Further, although not shown, polarizing plates 6a and 6b are respectively provided on the non-opposing sides of the substrates 1a and 1b.

Here, the scan electrode 2a and the display electrode 2b are generally formed of an indium oxide film, a tin oxide film, or the like.

The substrates 1a and 1b are, for example, transparent glass plates, but transparent plastic plates can also be used.

Further, the alignment films 3a and 3b are also called molecular alignment layers, and a vertical alignment layer, a horizontal alignment layer, a tilt alignment layer, or the like is appropriately selected and used depending on what kind of liquid crystal substance is arranged and how.

Further, as the liquid crystal substance 4, nematic phase liquid crystal, smectic phase liquid crystal, or the like is used. These are Schiff bases,
Azo-based, azoxy-based, benzoate-based, biphenyl-based, terphenyl-based, cyclohexycarboxylic acid ester-based, phenylcyclohexane-based, biphenylcyclohexane-based, pyrimidine-based, dioxane-based, etc. To use.

Further, in order to align these liquid crystal molecules stably, an appropriate chiral substance may be appropriately added, but in some cases, an appropriate dye may be appropriately added and used.

In the case of performing color display, a color filter may be appropriately inserted and disposed inside the liquid crystal display device, or the polarizing plates 6a and 6b may be colored.

In the case of such a simple matrix type liquid crystal display block, a pixel is formed at a portion where a plurality of strip-shaped scanning electrodes 2a and display electrodes 2b intersect each other.

On the substrate 1a, the light receiving element 7a is provided on or outside the seal portion 15 in FIG. 1 corresponding to the sealing material 5 in FIG. 4, the distribution wiring 16a for distributing the output signal of the light receiving element 7a, and this distribution. Decoder switches 17a that operate to demodulate information about which electrode is selected by a signal supplied by the wiring 16a and supply a power supply voltage to a desired electrode are formed.

Next, all scan electrodes 2a are
Scan bus bar 1 for supplying power to the scan electrodes via 17a
It is connected to 1a. The scanning bus bar 11a extends to the corner of the substrate 1a and is connected to the lead terminal 12a.

Similarly, on the sealing portion 15 on the substrate 1a or on the outside thereof, the light receiving element 7b, the distribution wiring 16b for distributing the output signal of the light receiving element 7b, and which electrode is selected by the signal supplied by the distribution wiring 16b. Decoder switch 17b that operates to demodulate information about whether or not to supply the power supply voltage to a desired electrode.
Are formed respectively.

Then, as shown in the figure, the display electrode 2b provided on the substrate 1b
Are respectively connected to the decoder switches 17b on the substrate 1a at the ends of the substrate.

The display electrodes 2b are each connected to a display bus 11b for supplying power to the display electrodes via a decoder switch 17b. The display bus bar 11b extends to one corner of the substrate 1a and is connected to the lead terminal 12b.

On the other hand, at the facing positions of the light receiving elements 7a, 7b, the light emitting elements 13a, 13b corresponding to the respective light receiving elements 7a, 7b are provided on the substrate 1a.
It is disposed on a substrate 14 (not shown) facing the.

For the light receiving elements 7a and 7b, PbS, PbSe, InAs or the like, which generally has a remarkable photoconductive effect in the infrared light region, can be used. In this case, GaAlAs, GaAsP or the like can be used as the light emitting elements 13a and 13b.

Here, as the light receiving elements 7a and 7b, individual components such as a chip of a general-purpose optical switch may be chip-on on the substrate 1a.1b, but the light receiving element is finely processed by thin film technology on the substrates 1a and 1b. You may make it each form 7a, 7b.

As shown in FIG. 1, the light receiving elements 7a and 7b are formed on the same substrate 1a.
However, when the light receiving element 7a is mounted on the substrate 1a and the light receiving element 7b is mounted on the substrate 1b as shown in FIG. 6 of the conventional example, the light receiving elements 7a and 7b are respectively mounted on the substrate. 1
It will be mounted on the opposite faces on a and 1b.

Therefore, in this case, the light emitting elements 13a and
In order to receive the light from 3b, since the substrates 1a and 1b are transparent, the light receiving element 7a should be attached upside down.

Regarding the light emitting elements 13a and 13b, a general-purpose light emitting element chip may be hybrid-configured on the substrate 14, or may be monolithically integrated with the substrate 14.

It should be noted that the light receiving elements 7a, 7b and the light emitting element 1a, 7b and the light emitting element 13a, 13b are operated so that they always operate in mutual correspondence.
Optical directivity may be enhanced by providing an optical hood or an optical louver made of glass fiber or the like between the optical fibers 3a and 13b.

If the light hood or the light louver is used as described above, the light emitting elements 13a and 13b can be arranged at positions apart from the light receiving elements 7a and 7b.

Next, the operation will be described. A power supply voltage is supplied to the scan bus 11a via the terminal 12a, and the decoder switches 17a connected to the scan electrodes 2a are sequentially turned on to sequentially supply the power supply voltage. The control of the decoder switch 17a will be described.

The light emitting element 13a transmits, for example, a plurality of bits of information, such as a power supply voltage, to be supplied to the scan electrode 2a, and transmits the information to the light receiving element 7a by light. The light receiving element 7a receives this optical signal, converts it into an electrical signal, and supplies the same signal to each decoder switch 17a via the distribution line 16a.

Each decoder / switch 17a operates to demodulate (decode) information regarding which electrode is selected and, when applicable, supply a power supply voltage to a desired electrode.

Similarly, the light emitting element 13b transmits information to the display electrode 2b to which the power supply voltage is supplied, for example, by encoding a plurality of bits and transmitting the information to the light receiving element 7b by light. The light receiving element 7b receives this optical reception, converts it into an electrical signal, and supplies the same signal to each decoder switch 17b via the distribution line 16b.

Each decoder / switch 17b operates so as to demodulate (decode) information regarding which electrode is selected and, when applicable, supply a power supply voltage to a desired electrode.

Here, when the light emitting elements 13a, 13b are appropriately selected to emit light, the light receiving elements 7a, 13b corresponding to the respective light emitting elements 13a, 13b,
7b receives this optical signal, converts it into an electrical signal, and distributes it.
The same signal is sent to each decoder switch 17 via 16a and 16b.
Supply to a and 17b.

Each of the decoder switches 17a and 17b inputs the signal through the distribution lines 16a and 16b, and also passes the signal in a form of passing through the distribution lines 16a and 16b to the adjacent decoder switch 17a.
Supply to a and 17b.

Then, each decoder switch 17a, 17b demodulates (decodes) information about which electrode is selected, and if applicable, the scan bus bar 11a to the desired scan electrode 2a and the display bus bar 11b to the desired display. A power supply voltage can be applied to the electrode 2b, and an image can be appropriately displayed.

FIG. 2 is a perspective view showing a state in which the liquid crystal display blocks of FIG. 1 are arranged in a mosaic pattern. 2, the same parts as those in FIG. 1 are designated by the same reference numerals.

A plurality of liquid crystal display blocks described in FIG. 1 are arranged in a mosaic pattern vertically and horizontally, and a scanning bus bar is provided for each liquid crystal display block.
Since it is only necessary to electrically connect only the liquid crystal display block adjacent to 11a and the display busbar 11b, the lead terminals 12a, 12b provided at the four corners of each liquid crystal display block are actually used, and the wires 18a, 18b, etc. are used. The adjacent liquid crystal display blocks are connected to each other by using. Therefore, a large-screen matrix type liquid crystal display device which is relatively easy to manufacture and has extremely high reliability can be realized.

FIG. 3 is an external view showing an embodiment of the matrix type display device of the present invention.

This display device includes a display device assembly 20 formed by arranging individual liquid crystal display blocks 19 vertically and horizontally,
A rear light source 21 for illumination disposed behind the display device assembly 20.
And a light reflection plate 22 arranged behind the light source 21.

Further, the front side of the display device assembly 20 and the display device assembly
Polarizing plates 6a and 6b are arranged between the light source 20 and the light source 21.

Further, the light emitting elements 13a, 13b are arranged on the light reflecting plate 22,
Light from the light emitting elements 13a and 13b is supplied to the light receiving elements 7a and 7b on the liquid crystal display block by the glass fiber 23.

It should be noted that in FIG.
Only the light transmission route to each liquid crystal display block is shown.

Therefore, even when a plurality of matrix type display devices are arranged in a mosaic pattern to form a large screen, the number of pixels of the connection lines supplied from the outside to each liquid crystal display block increases,
For example, two buses, a scanning bus bar and a display bus bar, may be used. The scanning bus bar and the display bus bar can be bridged to each other by using the appropriate four corners of each display block, and only one distribution line is required for each decoder switch. Since it is possible to supply a signal to the display block, it is not necessary to provide a band gap that cannot be displayed on the side surface of each display block, and the optical aperture ratio of the screen can be increased to 80% or more.

Therefore, according to the present invention, it is possible to provide a large-screen matrix liquid crystal display device which is relatively easy to manufacture, has extremely high reliability, and has a large optical aperture ratio of the screen.

The above description applies the present invention to a simple matrix type liquid crystal display device, but the present invention is also applicable to an active matrix type liquid crystal device.

The light receiving elements 7a and 7b and the decoder switches 17a and 17b are
Of course, they may be integrally formed by thin film technology, or individual parts may be used.

Also, if you use individual parts, if there is a margin in the height direction,
If three-dimensionally configured parts are selected so that the floor area is as small as possible, it becomes more space-saving than integrally forming by thin film technology, and in some cases the optical aperture ratio of the screen can be increased.

Further, in the embodiment of the present invention shown in FIGS. 1 to 3, transmission and transmission are performed using light, but this is not limited to light, and ultrasonic waves, radio waves, etc. are used to perform equivalent transmission. Of course, the function may be fulfilled.

(Effects of the Invention) Since the matrix type display device of the present invention is configured as described above, the optical signal received by the light receiving element is converted into an electrical signal, and the same decoder / switch is provided in one line. By supplying and demodulating the information of which electrode is selected here, the power supply voltage can be supplied to the desired electrode. Moreover, since the plurality of decoders / switches are composed of individual parts, the floor area can be reduced. Since it can be reduced, a large number of distribution lines are not required, and the optical aperture ratio of the screen can be improved, which is an extremely excellent effect in practical use.

[Brief description of drawings]

FIG. 1 is an exploded perspective view schematically showing an embodiment of a liquid crystal display block in a matrix type display device of the present invention, and FIG. 2 is a perspective view showing a state in which the liquid crystal display blocks of FIG. 1 are arranged in a mosaic pattern. 3 and 4 are external views showing one embodiment of the matrix type display device of the present invention, FIG. 4 is a schematic cross-sectional view of a conventional liquid crystal display block, and FIG. 5 is an undisplayable state in the conventional matrix type display device. FIG. 6 is a diagram showing a band-shaped void, and FIG. 6 is an exploded perspective view schematically showing a conventional liquid crystal display block. 1a, 1b, 14 ... Substrate, 2a ... Scan electrode, 2b ... Display electrode,
3a, 3b ... Alignment film, 4 ... Liquid crystal material, 5 ... Sealing material, 6a,
6b …… Polarizing plate, 7a, 7b …… Light receiving element, 8a, 8b …… Decoder, 9a, 9b, 16a, 16b …… Division wiring, 10a, 10b …… Switch circuit, 11a …… Scanning busbar, 11b …… Display bus, 12a, 12b ……
Terminals, 13a, 13b …… Light emitting element, 15 …… Seal part, 17a, 17b
...... Decoder switch, 18a, 18b ...... Wire, 19 ......
Liquid crystal display block, 20 ... Display assembly, 21 ... Illumination rear light source, 22 ... Light reflector, 23 ... Glass fiber.

Claims (1)

[Claims] 1. A matrix which is arranged above and below and to the left and right of a liquid crystal display block having a pair of substrates which are arranged in parallel with each other and in which a plurality of scan electrodes and display electrodes are insulated from each other and which are arranged in a matrix. In a flat-panel display device, a transmission element that transmits information regarding which electrode is selected from the plurality of scanning electrodes and display electrodes, a reception element that receives information from the transmission element, and an output signal of the reception element is By demodulating the information supplied to select which electrode, if applicable,
A matrix type display device characterized by comprising a liquid crystal display block including a plurality of decoder switches for driving respective corresponding electrodes, wherein the plurality of decoder switches are constituted by individual parts.