JPH11352907A - Display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the yield for a wiring board and to reduce the size of the wiring board, so as to reduce the cost and to attain compactification by arranging overlappedly a common wiring forming part for divided boards. SOLUTION: Divided boards 15a, 15b where a wiring board 14 is divided plurally to make an input terminal group 5 correspond to plurally divided respective blocks are connected. At least one portion of a common wiring forming part 12 of the boards 15a, 15b is arranged to be overlapped. Formation of through holes is reduced in the boards 15a, 15b, structure for the boards 15a, 15b is simplified, and yields of the boards 15a, 15b are improved. An yield of the board 14 composed of the plural boards 15a, 15b is improved thereby, and the size of the board 14 is reduced to provide an inexpensive and compact display.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device,
In particular, the present invention relates to a liquid crystal display device, a plasma display device, and the like.

[0002]

2. Description of the Related Art Conventional display devices include, for example, a liquid crystal display device and a plasma display device.

Here, a liquid crystal display device will be described as a specific example as a conventional display device. The liquid crystal display device is C
Compared to displays such as RT (Cathode Ray Tube), it has excellent features such as low power and light weight, and its product power has been enhanced by advances in peripheral technology, and it has been used in various products. In particular, in an active matrix type liquid crystal display device using a thin film transistor (hereinafter, referred to as a TFT) as a switching element for each pixel in a display area, a clear image display without crosstalk can be obtained. It is widely used in fields such as displays and displays for car navigation.

In general, in a liquid crystal display device, it is necessary to form a liquid crystal driving circuit for driving each pixel in a display area of the liquid crystal display panel in a liquid crystal display in a non-display area.
There is a method in which an IC chip or the like on which a liquid crystal driving circuit is formed is directly mounted on a glass substrate. Since this method is compact and has improved vibration resistance, the portability, which is a characteristic of the liquid crystal display device, is further increased, and this forming method is becoming mainstream. This connection method can be performed directly on the glass substrate.
COG (ChipOn Glas)
s) It is called the method.

Here, a liquid crystal display device in which a liquid crystal driving circuit is formed by the COG method will be specifically described as an example. As shown in FIG. 4, this liquid crystal display device includes a liquid crystal display panel 1, a semiconductor integrated circuit element 2 (hereinafter, referred to as an LSI element), and a wiring board 3.

The LSI element 2 includes a TFT (not shown) formed in each pixel of the display area 4a of the liquid crystal display panel 1.
Is switched to control each pixel to be driven by liquid crystal, and is mounted on the non-display area 4b by COG. In addition,
The LSI elements 2 include a signal line LSI element 2a and a scanning line LSI element 2b.

As shown in FIG. 5, an output terminal (not shown) of the LSI element 2 is connected to an output electrode 6 on a wiring extending from each TFT in the display area 4a to the non-display area 4b, and is connected to the input terminal of the LSI element 2. Terminals (not shown) are connected to the input electrodes 7 formed in the non-display area 4b.
The I element 2 is mounted by COG.

The input electrode 7 is for supplying a signal or power to the LSI element 2 and is formed so as to face an input terminal (not shown) of the LSI element 2. It is connected to the electrode 8.

As shown in FIG. 6, the wiring board connection electrode 8 is for facing and connecting to the wiring board electrode 10 of the wiring electrode group 9 formed on the wiring board 3. The input electrode 7 and the wiring board connection electrode 8 are formed for each signal supplied to the LSI element 2, and are collectively referred to as an input terminal group 5.

The wiring board 3 is connected to the input terminal group 5 formed in the non-display area 4 b so as to supply various signals and power to the LSI element 2. And a common wiring forming section 12 having a multilayer structure in which a plurality of common wirings 11 for supplying signals to the respective LSI elements 2 are formed. The common wiring 11 supplies a power supply, a reference voltage, various transfer clocks, control signals, and the like to the LSI element 2.
Are connected to necessary wiring board electrodes 10 so as to supply necessary input terminals (not shown). As shown in FIG. 6, a through hole 13 connecting between layers of the common wiring forming portion 12 is formed at a branch point of the common wiring 11.

The wiring board 3 is formed of a material such as a polyimide film so that it can be bent.
Thus, after the wiring board 3 is connected to the liquid crystal display panel 1, it is bent toward the liquid crystal display panel 1 to reduce the size from the front of the screen of the liquid crystal display device, thereby maintaining the compactness characteristic of the COG method. I'm sorry.

[0012]

However, among the conventional liquid crystal display devices, in the liquid crystal display device used for a monitor of a personal computer or the like, digitization and high definition are particularly advanced, and the number of signal lines is 600 or more. A number of about 1024 × RGB is required, and as shown in FIG.
About 6 to 10 elements 2a are mounted, and a single LS
When the number of input signal lines input to the I element 2 is large, the number is about 60.

Further, in order to strengthen the ground line for reducing the electromagnetic noise, it is necessary to insert a large ground line inside the wiring board 3. Therefore, in the conventional COG type liquid crystal display device as described above, as shown in FIG. 5, the common wiring forming portion 12 of the wiring board 3 needs to be multi-layered to about eight layers. 1
There is a problem that the size of the wiring board 3 is increased in order to secure the area of the wiring board 3.

Further, as the number of wiring boards 3 increases, the yield at the time of manufacturing the wiring boards 3 also decreases, and the wiring boards 3 become more expensive. In the case of a display device such as a plasma display device other than the liquid crystal display device, the same wiring board is used, and the same problem as described above occurs.

An object of the present invention is to provide an inexpensive and compact display device which improves the yield of wiring boards and reduces the size of the wiring boards.

[0016]

According to a display device of the present invention, a divided substrate obtained by dividing a wiring substrate into a plurality of parts so as to correspond to each of a plurality of blocks into which an input terminal group is divided is connected. The configuration is such that at least a part of the wiring forming portion is arranged so as to overlap.

According to the present invention, the yield of the wiring board can be improved and the size of the wiring board can be reduced, so that an inexpensive and compact display device can be provided.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is directed to a wiring electrode group connected to an input terminal group connected to a semiconductor integrated circuit element for performing a display operation on a display panel, and a wiring electrode group connected to an input terminal group. In a display device provided with a wiring board formed with a common wiring distributed and connected to necessary electrodes, a divided board obtained by dividing the wiring board into a plurality of pieces so as to correspond to each of the plurality of blocks into which the input terminal group is divided. The display device is configured so as to be connected and arranged so that at least a part of a common wiring forming portion of these divided substrates is overlapped and arranged, and the formation of through holes in each divided substrate can be reduced. Since the structure of the divided substrate can be simplified and the yield of the divided substrate can be improved, the yield of the wiring substrate including a plurality of divided substrates can be improved. Can also reduce the size of the wiring board, it is possible to obtain an inexpensive and compact display device.

According to a second aspect of the present invention, there is provided the display device according to the first aspect, wherein the distance from the wiring electrode group of the divided substrate to the common wiring forming portion is the same or substantially the same. A wiring board configured by arranging a plurality of divided boards in a compact manner can be obtained.

According to a third aspect of the present invention, there is provided the display device according to the first aspect, wherein the plurality of divided substrates constituting the wiring board are formed in the same wiring pattern. Manufacturing cost can be reduced.

Hereinafter, the display device of the present invention will be described based on specific embodiments. Here, a liquid crystal display device as a display device will be described as an example. (Embodiment) A liquid crystal display device according to an embodiment of the present invention
As shown in FIG. 1, divided substrates 15a and 15b obtained by dividing the wiring substrate 14 into two parts are connected to correspond to each block obtained by dividing the input terminal group 5 into two, and the common wiring 11 of these divided substrates 15a and 15b is connected. Are formed so that a part of the common wiring forming part 12 as the forming part of the above is overlapped and arranged.

Here, specifically, the signal line LSI element 2a
Board 15 obtained by dividing the wiring board 14 connected to the
The liquid crystal display device constituted by a and 15b will be described.
The input terminal group 5 connected to the signal line LSI element 2a includes:
As shown in FIG. 2, the non-display area 4 is divided into two blocks at the center of the signal line LSI element 2a.
b. The distance between adjacent blocks into which the input terminal group 5 is divided into two is set such that when the two divided substrates 15a and 15b constituting the wiring substrate 14 are connected, the divided substrates 15a and 15b do not interfere with each other. A distance is provided between the substrate 15a and the divided substrate 15b. In this embodiment, the distance L1 between the blocks is, for example, 1 mm. The input terminal group 5 and the output electrode 6 are formed simultaneously with the TFT by diverting a conductive thin film used for forming the TFT in the display area 4a.

The wiring board 14 is connected so as to correspond to each of the blocks obtained by dividing the input terminal group 5 into two, as shown in FIG.
As shown in (1), it is composed of a divided substrate 15a connected to the block on the left side of the input terminal group 5, and a divided substrate 15b connected to the block on the right side of the input terminal group 5. Further, the common wiring forming part 12 of the divided substrates 15a and 15b
As the side of the wiring electrode group 9 is divided into two parts, the number of wirings of the common wiring 11 is also divided into two parts.
The number of through-holes 13a and 15b is half that of the conventional wiring board 3 shown in FIG.
a, 15b are formed by the conventional wiring board 3
It has a multi-layer structure that is half of that of. In addition, each of the divided substrates 15a and 15b has the same distance L2 from the wiring electrode group 9 to the common wiring forming portion 12. In addition,
A plurality of divided boards 15a and 15b constituting the wiring board 14
Are formed with the same wiring pattern.

The wiring substrate 14 is made of a base material using a foldable material such as a polyimide film, and the portion where the wiring electrode group 9 is formed is a single-layer polyimide film. In 12, the common wiring 11 is branched so as to distribute and supply the signal (power supply, transfer clock, etc.) of the common wiring 11 to each required wiring board electrode 10 of the wiring electrode group 9. Part 1
2 has a multilayer shape. In this embodiment, a 25-μm-thick polyimide film is used in the portion where the wiring board electrode 10 is formed, to improve the bendability after connection.

The wiring board 14 and the LSI element 2 are made of an anisotropic conductive film (ACF: Anisotropic conductive film) in which conductive particles obtained by plating a resin ball with gold are dispersed in a thermosetting epoxy resin.
It is joined to the liquid crystal display panel 1 via a conductive film.

When the divided substrates 15a and 15b are connected to the liquid crystal display panel 1, the wiring board electrodes 10 of the wiring electrode group 9 of the divided substrates 15a and 15b are in contact with each other for each block obtained by dividing the input terminal group 5 into two. After the divided substrates 15a and 15b are respectively aligned (temporarily fixed), they are fully bonded. At this time, these divided substrates 1
5a and 15b are arranged so that a part of the common wiring forming part 12 is overlapped.

With such a configuration, the signal line LSI
Since the divided substrates 15a and 15b obtained by dividing the wiring board 14 into two corresponding to blocks obtained by dividing the input terminal group 5 connected to the element 2a into two, respectively, are used.
Since the number of electrodes individually assigned to 5a and 15b can be reduced, the number of through holes 13 formed in divided substrates 15a and 15b is reduced to half of the number of through holes 13 of conventional wiring board 3. Can be divided into divided substrates 15
The multi-layered structure of the wiring boards 3 can be made a half layer as compared with the conventional wiring board 3 and the structure of the divided boards 15a and 15b can be simplified. Accordingly, the problem that the yield is reduced can be solved and the yield can be improved.

Further, the width D2 of the common wiring forming portion 12 of the divided substrates 15a and 15b can be made smaller than the width D1 of the common wiring forming portion 12 of the conventional wiring substrate 3, and the structure is composed of the divided substrates 15a and 15b. Since the size of the wiring substrate 14 to be formed can be made smaller than that of the conventional wiring substrate 3, the divided substrates 15a and 15b have the same distance L2 from the wiring electrode group 9 to the common wiring forming portion 12, so that the divided substrates 15a and 15b are divided. When the substrates 15a and 15b are connected to the liquid crystal display panel 1, the common wiring forming portions 12 of the divided substrates 15a and 15b are arranged so as to partially overlap each other, so that the compactness characteristic of COG can be obtained. Thus, an inexpensive and compact liquid crystal display device can be obtained.

The divided substrate 1 constituting the wiring substrate 14
Since 5a and 15b are formed with the same wiring pattern, the manufacturing cost can be greatly reduced. In this embodiment, the wiring board 14 connected to the signal line LSI element 2a is composed of divided substrates 15a and 15b, but the wiring board 14 connected to the scanning line LSI element 2b is divided. The same effect can be obtained even in the case of using the divided substrates 15a and 15b.

In this embodiment, two divided substrates are connected to the input terminal group of a single LSI element.
The same effect is obtained even when a plurality of divided substrates are connected to the input terminal group of a single LSI element.

In this embodiment, the case of a liquid crystal display device has been described. However, similar effects can be obtained in the case of a display device other than a liquid crystal display device such as a plasma display device.

[0032]

As described above, according to the display device of the present invention, the divided substrate obtained by dividing the wiring substrate into a plurality of parts is connected so as to correspond to each of the plurality of divided blocks of the input terminal group.
By configuring such that at least a part of the common wiring forming portion of these divided substrates is arranged to be overlapped, the number of through holes formed in each divided substrate is compared with the number of through holes of the conventional wiring substrate. Since the number of wiring boards can be reduced, and the wiring board can be composed of a divided board having a simple structure, a wiring board with a high yield can be obtained. Further, the size of the wiring board can be made smaller than that of a conventional wiring board, and an inexpensive and compact display device can be obtained.

In the case of a display device in which the distance from the wiring electrode group of the divided substrate to the common wiring forming portion is the same or substantially the same, a wiring substrate constituted by compactly arranging a plurality of divided substrates is obtained. be able to.

In the case of a display device in which a plurality of divided substrates constituting a wiring substrate are formed with the same wiring pattern,
The manufacturing cost can be greatly reduced as compared with a wiring board composed of a plurality of different types of divided boards.

[Brief description of the drawings]

FIG. 1 is a plan view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of the liquid crystal display device of the embodiment.

FIG. 3 is a plan view of a divided substrate of the liquid crystal display device of the embodiment.

FIG. 4 is a plan view of a conventional liquid crystal display device.

FIG. 5 is a partially enlarged view of a conventional liquid crystal display device.

FIG. 6 is a plan view of a wiring substrate of a conventional liquid crystal display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal display panel 2 Semiconductor integrated circuit element 4a Display area 4b Non-display area 5 Input terminal group 9 Wiring electrode group 10 Wiring board electrode 11 Common wiring 12 Common wiring forming part 13 Through hole 14 Wiring board 15a Divided board 15b Divided board

Claims (3)

[Claims] 1. A wiring electrode group connected to an input terminal group connected to a semiconductor integrated circuit element for performing a display operation on a display panel, and a common wiring distributed and connected to necessary electrodes of the wiring electrode group. In a display device provided with a wiring substrate, the divided wiring substrate is divided into a plurality of divided substrates so as to correspond to each of the divided blocks of the input terminal group, and a common wiring forming portion of these divided substrates is formed. A display device configured to be at least partially overlapped. 2. The display device according to claim 1, wherein the distance from the wiring electrode group on the divided substrate to the common wiring forming portion is the same or substantially the same. 3. The display device according to claim 1, wherein the plurality of divided substrates forming the wiring substrate are formed in the same wiring pattern.