JP2000292805A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To expand an arrangement area of an internal drive circuit and to actualize both SOG implementation and compacting. SOLUTION: An image matrix substrate which has internal drive circuits 5a, 5b, 5c, and 5d arranged at a periphery of a pixel area 4 and also has an external signal input terminal 6 and an opposite substrate 2 which has internal drive circuits 11a, 11b, 11c, and 11d at the periphery of an image BM area 9 and also has an external signal input terminal 12 are stuck together. On the external signal input terminals 6 and 12 which project orthogonally to each other, electrodes of FPC 10 whose terminal surfaces face internally opposite each other are mounted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device having a built-in peripheral driving circuit and made of a polysilicon thin film transistor or the like.

[0002]

2. Description of the Related Art In recent years, advances in fine processing technology, material technology, high-density packaging technology, and the rapid spread of multimedia equipment have resulted in a wide range of screen sizes,
The ratio of liquid crystal display devices in various applications such as A, in-vehicle, and information communication is rapidly expanding, and is attracting the attention of the entire electronics industry as a key device replacing CRT. Under such circumstances, the thin and light weight unique to liquid crystal display devices has been further advanced, and product areas (for example, A4, B5 size notebook PCs, sub-notebook PCs, mobile PCs, DIN standard compliant car navigation systems) that were difficult to achieve with CRTs System, monitor-integrated video movie, pen input type portable information terminal, etc.)
In particular, active development of a liquid crystal display device using a polysilicon thin film transistor that enables the incorporation of a peripheral drive circuit has been active. Recently, not only a drive circuit but also a DAC, a memory element, a solar cell, a tuner, and the like have been incorporated. T SOG (sy
Stem glass panels have also been proposed.

First, a schematic configuration of a conventional liquid crystal display device incorporating a peripheral driving circuit using a polysilicon thin film transistor will be described with reference to FIG.

In FIG. 4, 1 is a pixel matrix substrate,
Reference numeral 2 denotes a counter substrate, which is bonded to form a liquid crystal display device 3 in which a gap is filled with a liquid crystal material. Here, the pixel matrix substrate 1 is a diagram viewed from the pattern surface, and the counter substrate 2 is a diagram viewed from the non-pattern surface (substrate back surface). The liquid crystal display device 3 is a diagram in which the pattern surfaces of the pixel matrix substrate 1 and the counter substrate 2 are attached to each other and viewed from the non-pattern surface of the counter substrate 2. Hereinafter, the perspective directions of the drawings including the embodiment will be unified. The liquid crystal display 3
For the sake of convenience, the drawing is viewed from the non-pattern surface (substrate back surface) of the counter substrate 2, so that components on the counter substrate side on the upper surface with respect to the viewing direction are depicted in the drawing.

A pixel matrix substrate 1 is provided with a thin film transistor provided with a pixel electrode which is an element for controlling an optical transmission characteristic by applying an electric field to a liquid crystal. Built-in drive circuits 5a, 5b, 5c, 5d are arranged. These built-in drive circuits are constituted by a scan circuit, a buffer circuit, a level shifter circuit, and the like, and are driven by supplying a signal from an external signal input terminal 6 via a bus line. Reference numerals 7a and 7b denote opposing terminals for electrically connecting the pixel matrix substrate 1 and the opposing substrate 2, and are usually connected by applying a conductive paste containing carbon or metal balls.

[0006] The counter substrate 2 has a pixel BM (black matrix) corresponding to the pixel region 4 of the pixel matrix substrate 1.
x) a transparent electrode is formed around the region 8 so as to surround the peripheral BM region 9, and further, a transparent electrode is formed on the entire substrate;
It is configured so that it can be connected to the opposite terminals 7a and 7b of the pixel matrix substrate 1.

The liquid crystal display device 3 includes a pixel matrix substrate 1
A liquid crystal material is filled in the gap where the substrate and the counter substrate 2 are bonded. 10 is an FPC mounted on the external signal input terminal 6
(Flexible printed circuit), which has a function of supplying a signal from an external circuit to a built-in drive circuit.

Conventionally, built-in drive circuits 5a, 5b, 5c, 5
d is formed only on the periphery of the pixel region 4 on the pixel matrix substrate 1 side, and on the counter substrate 2 side, a black matrix pattern or a color layer, which is a light-shielding layer made of metal or resin, as described above. And only a transparent electrode such as ITO and a surface protective layer are provided.

[0009]

However, in the above-mentioned conventional liquid crystal display device, the area where the built-in drive circuit is arranged is limited to the periphery of the image display area on the side of the polysilicon thin film substrate having the pixel matrix. However, there is a limit to the circuit scale that can be built. On the other hand, in pursuit of compactness, a feature of liquid crystal display devices, there is a trend to further reduce the peripheral frame area that does not contribute to image display, and the area where circuits can be built tends to be smaller. It is. In order to take advantage of the features of liquid crystal display devices using polysilicon thin film transistors and actively incorporate and incorporate external circuits, it is essential to expand the circuit scale. It was a situation that could lead to a trade-off.

[0010] An object of the present invention is to provide a useful structure of a liquid crystal display device in order to solve the above conventional problems.

[0011]

Therefore, a liquid crystal display device according to a first aspect of the present invention is a liquid crystal display device having a built-in peripheral drive circuit, wherein the peripheral drive circuit is opposed to a pixel matrix substrate bonded thereto. It is characterized by being arranged on both of the substrates.

According to the liquid crystal display device of the first aspect, the area for disposing the built-in drive circuit can be enlarged. Therefore, both SOG and compactness can be achieved.

The liquid crystal display device according to a second aspect is characterized in that, in the first aspect, the external signal input terminal is arranged on both the bonded pixel matrix substrate and the opposing substrate. .

According to the liquid crystal display device of the second aspect, in addition to the function of the first aspect, an external signal input terminal equivalent to that of the pixel matrix substrate is provided on the opposite substrate side, so that a sophisticated built-in drive circuit is provided. Can be arranged, and the function can be improved.

According to a third aspect of the present invention, there is provided a liquid crystal display device.
Wherein the external signal input terminal surfaces face each other.

According to the liquid crystal display device of the third aspect, in addition to the function of the second aspect, the built-in drive circuit and the external signal input terminal on the opposite substrate side and the black matrix and the transparent electrode required for the original function are the same. The formation on the surface simplifies the manufacturing process. Further, since the FPC mounting surfaces face inward each other, there is no increase in the thickness direction, and the thickness can be reduced.

According to a fourth aspect of the present invention, there is provided a liquid crystal display device.
In the above, the terminal forming sides of the substrate on which the external signal input terminals are arranged are partially cut out, and the parts on which the external signal input terminals are arranged are formed in the notched portions of the bonded pixel matrix substrate and the counter substrate on the other side. And has a structure that does not overlap.

According to the liquid crystal display device of the fourth aspect, in addition to the function of the second aspect, the external signal input terminals can be arranged adjacent to each other in parallel, so that the mounting space can be reduced. And contribute to further downsizing.

The liquid crystal display device according to the fifth aspect is the first aspect.
Does not have an external signal input terminal on the counter substrate side, an input signal to a peripheral drive circuit arranged on the counter substrate side is input from an external signal input terminal on the pixel matrix substrate side, and an electrical connection is established between the substrates. The input is made via a connection terminal connected to the terminal.

According to the liquid crystal display device of the fifth aspect, in addition to the function of the first aspect, the means for supplying a signal to the built-in drive circuit on the counter substrate side is simplified, and the flexible printed circuit (FPC) is provided.
A member structure such as a rinted circuit is not complicated, and an increase in cost can be suppressed.

[0021]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a schematic diagram of a liquid crystal display device according to Embodiment 1 of the present invention. The same parts as those of the conventional liquid crystal display device shown in FIG.

In FIG. 1, reference numeral 1 denotes a pixel matrix substrate, and the configuration is exactly the same as that of FIG. Counter substrate 2
Is arranged so as to surround the pixel BM region 8 and the peripheral BM region 9 and further has a transparent electrode formed on the entire substrate as in FIG. Area 9 includes built-in drive circuits 11a, 11b, 11c,
11d, and an external signal input terminal 1 to which signals are supplied to these built-in drive circuits via bus lines.
2 is provided.

The liquid crystal display device 3 includes a pixel matrix substrate 1
And the opposing substrate 2 are bonded together, and the gap is filled with a liquid crystal material. Reference numeral 10 denotes an FPC mounted on both the external signal input terminal 6 and the external signal input terminal 12, and the mounting terminal side is divided into two parts.

In the case of the first embodiment, the terminal forming sides 13, 1 of the pixel matrix substrate 1 and the counter substrate 2 which are bonded together.
4 project perpendicularly to each other, and
It is assumed that the terminal surfaces on which the ten electrodes are mounted face inside facing each other. At this time, in order to enable connection to both the pixel matrix substrate 1 and the opposing substrate 2 with one FPC 10, the mounting terminal surface of the FPC 10 has a structure in which the mounting terminal surface is divided in the front and back directions.

According to the liquid crystal display device configured as described above, the built-in driving circuits 11a, 11b, 1
1c and 11d can be arranged and an external signal can be supplied. A larger driving circuit, which cannot be built in only by the pixel matrix substrate 1, is built in without increasing the frame area. be able to. Therefore, a highly functional liquid crystal display device can be obtained without impairing the advantage of compactness.

(Embodiment 2) FIG. 2 is a schematic configuration diagram of a liquid crystal display device according to Embodiment 2 of the present invention. Since the liquid crystal display device according to the second embodiment has basically the same configuration as the liquid crystal display device according to the first embodiment, the same components are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 2, reference numeral 1 denotes a pixel matrix substrate, which has the same basic configuration as that of FIG. 1, except that a part of the terminal forming side 13 of the pixel matrix substrate 1 of FIG. It has a structure in which the portion 15 is formed.

Reference numeral 2 denotes a counter substrate, which has the same basic structure as that of FIG. 1, except that a portion corresponding to the cutout portion 15 of the pixel matrix substrate 1 is used instead of the terminal forming side 14 of the counter substrate 2 in FIG. The external signal input terminal 12 is formed in a part of the terminal formation side 14, and a cutout 16 is formed in a portion corresponding to the external signal input terminal 6 of the pixel matrix substrate 1.

The liquid crystal display device 3 includes a pixel matrix substrate 1
And the counter substrate 2 are bonded together, and the gap is filled with a liquid crystal material. Reference numeral 10 denotes an FPC mounted on both the external signal input terminal 6 and the external signal input terminal 12. The mounting terminal side is divided into two parts, and the mounting terminal surface is turned upside down so as to be connectable to each substrate. It has the same structure as that of FIG.

In the case of the second embodiment, the terminal forming sides 13 and 14 of the pixel matrix substrate 1 and the counter substrate 2 which are bonded together.
Are formed so as to project in the same direction, and the external signal input terminals 6 and 12 are bonded to each other so as to correspond to the notch 16 and the notch 15 of the other party. A structure in which surfaces do not overlap each other can be adopted.

According to the liquid crystal display device of the second embodiment configured as described above, the external signal input terminals 6, 12
Since the terminal forming sides 13 and 14 of each substrate provided with are arranged only in one direction of the liquid crystal display device, an increase in the frame area can be suppressed to a minimum. In addition, since the external signal input terminals 6 and 12 can be arranged adjacent to each other, the FP
The area of C10 can be reduced, and a reduction in component costs can be expected. As a result, a more compact and lower cost liquid crystal display device with a built-in high function can be obtained.

(Embodiment 3) FIG. 3 is a schematic configuration diagram of a liquid crystal display device according to Embodiment 3 of the present invention. Since the liquid crystal display device according to the third embodiment has basically the same configuration as the liquid crystal display device according to the first embodiment, the same components are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 3, reference numeral 1 denotes a pixel matrix substrate, which has the same basic structure as that of FIG.
In addition to 7b, a connection terminal 17 is arranged on the pixel matrix substrate side. The connection terminal 17 is connected to the external signal input terminal 6 by a bus line, and has a function of supplying a signal to be transmitted to the built-in drive circuits 11a, 11b, 11c, 11d on the counter substrate 2 side.

On the other hand, connection terminals 18 are also provided on the counter substrate 2 side in a form corresponding to the connection terminals 17, and the built-in drive circuits 11a, 11b, 11c, 1 are connected via bus lines.
1d.

The liquid crystal display device 3 includes a pixel matrix substrate 1
And the counter substrate 2 are bonded together, and the gap is filled with a liquid crystal material. Reference numeral 10 denotes an FPC mounted on the external signal input terminal 6, which is not of a special structure in which the mounting surface is divided into two parts as shown in the first and second embodiments, and the mounting terminal surface is one. It has a strip-like structure provided in the direction. The connection terminals 17 and 18 are electrically connected to each other with a conductive paste interposed therebetween, and the same material is applied in the same process as the conductive paste applied to the opposed terminals 7a and 7b.

According to the liquid crystal display device configured as described above, the built-in drive circuits 11a and 11
FP as means for inputting signals to b, 11c, 11d
Since it is not necessary to directly connect C or the like to the counter substrate 2, the structures of the liquid crystal display device and the FPC can be simplified. In addition, since the conductive paste is used as a conductive medium, it can be produced in a conventional manufacturing process, and does not require any new equipment. As a result, a more compact and lower cost liquid crystal display device with a built-in high function can be produced at the same member cost and manufacturing cost as the conventional one.

[0038]

As described above, according to the first aspect of the present invention, the area for disposing the built-in drive circuit can be expanded, and thus both SOG and compactness can be achieved.

According to the second aspect of the present invention, in addition to the function of the first aspect, since the opposite substrate is provided with a signal input terminal equivalent to that of the pixel matrix substrate, an advanced built-in drive circuit is provided. The arrangement can be performed, and the function can be improved.

According to the third aspect of the invention, in addition to the function of the second aspect, the built-in drive circuit on the opposite substrate side and the external signal input terminal, and the black matrix and the transparent electrode required for the original function are the same. The formation on the surface simplifies the manufacturing process. Further, since the FPC mounting surfaces face inward each other, there is no increase in the thickness direction, and the thickness can be reduced.

According to the fourth aspect of the invention, in addition to the function of the second aspect, the external signal input terminals can be arranged adjacent to each other in parallel, so that the mounting space can be reduced. And contribute to further downsizing.

According to the fifth aspect of the present invention, in addition to the function of the first aspect, the means for supplying signals to the built-in drive circuit on the counter substrate side is simplified, and the flexible printed circuit (FPC) is provided.
A member structure such as a rinted circuit is not complicated, and an increase in cost can be suppressed.

With the above effects, while pursuing compactness which is a feature of the liquid crystal display device and reducing the peripheral frame area, while expanding the scale of the built-in circuit in the flow of SOG, A useful structure utilizing the features of the liquid crystal display device can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a liquid crystal display device according to Embodiment 1 of the present invention.

FIG. 2 is a schematic configuration diagram of a liquid crystal display device according to Embodiment 2 of the present invention.

FIG. 3 is a schematic configuration diagram of a liquid crystal display device according to Embodiment 3 of the present invention.

FIG. 4 is a schematic configuration diagram of a conventional liquid crystal display device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Pixel matrix substrate 2 Counter substrate 3 Liquid crystal display device 4 Pixel area 5a, 5b, 5c, 5d, 11a, 11b, 11c, 1
1d Built-in drive circuit 6, 12 External signal input circuit 7a, 7b Opposite terminal 8 Pixel BM area 9 Peripheral BM area 10 FPC 13, 14 Terminal formation side 15, 16 Notch 17, 18 Connection terminal

Claims (5)

[Claims] 1. A liquid crystal display device having a built-in peripheral drive circuit, wherein the peripheral drive circuit is disposed on both a pixel matrix substrate and a counter substrate bonded to each other. 2. The liquid crystal display device according to claim 1, wherein the external signal input terminals are arranged on both the bonded pixel matrix substrate and the opposing substrate. 3. The liquid crystal display device according to claim 2, wherein the external signal input terminal surfaces face each other. 4. A terminal forming side of a substrate on which an external signal input terminal is disposed is partially cut away, and a portion on which an external signal input terminal is disposed is connected to a pixel matrix substrate and a counter substrate which are bonded to each other. 3. The liquid crystal display device according to claim 2, wherein the liquid crystal display device has a structure that is located in the notch and does not overlap. 5. An external signal input terminal is not provided on the counter substrate side, and an input signal to a peripheral drive circuit disposed on the counter substrate side is input from an external signal input terminal on the pixel matrix substrate side. 2. The liquid crystal display device according to claim 1, wherein the input is made via a connection terminal for electrically connecting the devices.