JPH0830814B2 - Liquid crystal display - Google Patents

Description

The present invention relates to a liquid crystal display device, which reduces the resistance of a bus line to enable driving from one side of the bus line, eliminates the restriction on the number of bus line disconnection repairs, and improves the reliability of the repair. For the purpose of increasing the number of pixels, a plurality of pixel electrodes arranged in a matrix on the surface of one side of the pair of insulating substrates facing each other, and a plurality of pixel electrodes corresponding to rows or columns. Having a plurality of bus lines arranged, and on the surface of the transparent other side substrate,
A black pattern made of a stripe-shaped non-translucent conductive film for shielding light around each pixel electrode is provided at both ends of the black pattern and both ends of the corresponding bus line corresponding to the bus line in at least one direction. The connection ends are arranged so as to face each other, and the connection ends facing each other can be electrically connected.

[Industrial applications]

The present invention relates to a liquid crystal display device, and more particularly to a structure of an active matrix type liquid crystal display device capable of repairing disconnection of a bus line.

In recent years, a thin film transistor drive type liquid crystal display device is desired to have a large screen and high image quality. Therefore, the number of bus lines and TFT elements tends to increase, but with this, various defects also increase.

The main defects are short circuit between gate and drain and disconnection of bus line.
A redundant configuration using one element is adopted.

On the other hand, it is necessary to reduce the number of drive circuits in order to reduce the size and cost while increasing the screen size.
It is necessary to lower the bus line resistance so that the bus line can be driven on one side.

It is also necessary to be able to repair defects such as disconnection in a short time and with high reliability.

[Conventional technology]

FIG. 4 shows a main part of a conventional active matrix type liquid crystal display device.

The liquid crystal display device shown in the figure is an example in which drive circuits 52 are provided on both sides of the bus line 51 in order to prevent the drive voltage pulse from being rounded by the resistance of the bus line 51. In this configuration, since the bus line 51 is driven from both sides, even if the bus line 51 is disconnected, the pixels on this bus line 51 will not be disabled.

However, since two sets of the drive circuits 52 are provided, the manufacturing cost becomes high and the display unit becomes large.

FIG. 5 is a view showing another conventional configuration, in which the broken bus line 5
This is an example in which redundant wiring 53 for repairing 1'is provided.

In this configuration, even if a disconnection occurs in the bus line 51 ', both ends of the disconnected bus line 51' and the redundant wiring are
It is possible to repair the disconnection by connecting 53 with wire bonding.

However, the number of redundant wirings 53 that can be arranged is limited to about one or two. Therefore, if the number of disconnection is one or two, it can be repaired. The panel cannot be used.

[Problems to be Solved by the Invention]

As described above, in the configuration of the conventional liquid crystal display device, in order to prevent the liquid crystal panel from being unnecessarily enlarged, the area other than the pixel portion cannot be made large. If there were many breaks in the line, the panel was irreparable. In addition, there is a problem that the reliability of the repair is poor, such as the wire coming off when the panel is shocked, and a problem that the repair takes a long time even after the repair.

Furthermore, since two sets of drive circuits are provided, there is a limit to downsizing the liquid crystal display device.

It is an object of the present invention to reduce the resistance of a bus line to enable driving from one side of the bus line, remove the restriction on the number of bus line disconnection repairable, and improve the reliability of the repair.

[Means for solving the problem]

In the present invention, stripe-shaped black patterns made of a non-translucent conductive material are arranged parallel to the bus lines corresponding to at least one type of bus lines.

[Action]

Since the black patterns are arranged in parallel with each other corresponding to each of the predetermined bus lines, both ends of the bus lines are short-circuited by the black patterns by connecting both ends of the corresponding black patterns and the bus lines. It

Therefore, the black pattern can be used for repairing the disconnection of the bus line and for disposing the driving circuit on only one side.

〔Example〕

 The present invention will be described below with reference to examples.

1 and 2 are views showing an embodiment of the present invention, FIG. 1 is a plan view of an essential part, and FIG. 2 is a cross-sectional view of the essential part. Explain.

In the figure, 1 is a striped black pattern made of a non-translucent conductive film such as Cr (chrome) film, 2 is a drain bus line, 3 is a pixel electrode, and 21 and 22 are transparent insulating substrates. .

The present embodiment is an example in which the stripe-shaped black pattern 1 is formed in parallel with the drain bus line 2 and at a position covering the column of the pixel electrodes 3 connected to the same drain bus line 2. Needless to say, the black pattern 1 is opened immediately above each pixel electrode 3.

The drain bus line 2 is formed on the transparent insulating substrate 21 and the TFT substrate 5 on which the pixel electrodes 3 and thin film transistors for driving the pixel electrodes 3 are arranged. It is formed on the surface of the transparent insulating substrate 22 facing the TFT substrate 5 with the liquid crystal 4 sandwiched therebetween. In addition to the black pattern 1, a color filter 31, an acrylic resin film 32, an ITO film 33 forming a counter electrode, and the like are formed on the transparent insulating substrate 22.
The counter substrate 6 is formed.

In the present embodiment, the mutual positional relationship between the black pattern 1 and the drain bus line 2 is arranged so that one is located in the other. That is, the gap between two adjacent black patterns 1 is arranged immediately above the drain bus line 2. It is desirable that this gap be as small as possible, and in this embodiment, it is set to about 5 μm.

Furthermore, each black pattern 1 and each drain bus line 2
At both ends, connection ends 8 and 9 for connecting the both are provided so as to face each other vertically.

Spacers 10 having a diameter of about 5 μm are dispersed between the TFT substrate 5 and the counter substrate 6 as usual to define the distance between both substrates, that is, the thickness of the liquid crystal 4. The liquid crystal 4 is sealed between the TFT substrate 5 and the counter substrate 6 with a sealant 7.

When the drain bus line 2 is disconnected in this embodiment having the above-described configuration, as shown in FIG. 2, the connection ends 9 at both ends of the drain bus line 2 that are disconnected and the black pattern opposite thereto are connected. The connection end 8 of No. 1 is melted and connected by laser shot. As a result, the disconnection of the drain bus line 2 is repaired.

Moreover, in the configuration of the present embodiment, since the same number of black patterns 1 can be provided corresponding to each drain bus line 2, even if a large number of disconnections of the drain bus line 2 occur, they can all be repaired.

Further, regardless of whether the drain bus line 2 is broken or not, if the drain bus line 2 and the corresponding black pattern 1 are all connected, the resistance of the drain bus line 2 can be reduced.

Next, a modified example of the present invention will be described with reference to FIGS. 3 (a) and 3 (b). FIG. 3 (a) is a cross-sectional view of a main part and FIG. 3 (b) is a plan view of the main part. The same parts as those in FIGS. 1 and 2 described above are denoted by the same reference numerals.

This modification is an example in which the black patterns 1 are arranged in parallel to the gate bus lines 11, and each black pattern 1 is formed so as to cover all the pixel electrodes 3 connected to the same gate bus line 11. However, an opening is provided on each pixel electrode 3 so that the black pattern 1 does not exist, as in the case of the first embodiment.

The connection ends 8 and 12 are arranged opposite to each other at both ends of the black pattern gate bus line 11, and the TFT substrate 5 and the counter substrate 6 are bonded to each other with the sealant 7 at the positions of the connection ends 8 and 12.

In this modification, as the sealant 7, a normal sealant mixed with an anisotropic conductive material is used. As a result, the black pattern 1 and the connecting ends 8 and 12 of the gate bus line 11 which are vertically opposed to each other via the sealant 7 are electrically connected to each other, and the both ends of the gate bus line 11 correspond to each other. Short circuit. Therefore, even if a disconnection occurs in the gate bus line 11 itself,
11 does not cause disconnection failure.

Further, since both ends of the gate bus line 11 are short-circuited as described above, the signal applied to the gate bus line 11 is input to both sides. Therefore, even if the drive circuit is provided on only one side, the drive circuit is effectively driven on both sides. Therefore, the drive circuit only needs to be provided on one side, and the liquid crystal display device can be downsized.

In the above-mentioned one embodiment and the modification, the black pattern 1 is arranged corresponding to one bus line, but if the black pattern 1 is laminated with the insulating film interposed,
It is also possible to arrange the black hat turn 1 corresponding to two or more bus lines.

The material of the black pattern 1 is not limited to the Cr film used in the above-described embodiment, and an Al film having a low resistivity may be used.

〔The invention's effect〕

As described above, according to the present invention, it is possible to remove the restriction on the number of repairable disconnections without changing the other process only by changing the structure of the black pattern on the counter substrate side. Not only is the stay improved,
The resistance of the bus line can be reduced, the liquid crystal display device can be driven on one side, and the cost can be reduced and the size can be reduced.

[Brief description of drawings]

FIG. 1 is a structural explanatory view of an embodiment of the present invention, FIG. 2 is an explanatory view of disconnection repair of the above-described one embodiment, FIGS. 3 (a) and 3 (b) are explanatory views of a modification of the present invention, and FIG. FIG. 5 and FIG. 5 are views for explaining conventional problems. In the figure, 1 is a black pattern, 2 is a drain bus line, 3 is a pixel electrode, 4 is a liquid crystal, 5 is a TFT substrate, 6 is a counter substrate, 7 is a sealant, and 8, 9 and 12 are connection ends.

Front page continued (72) Inventor Jun Inoue 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited (72) Inventor, Norio Nagahiro 1015, Kamedotachu, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited (72) Inventor Yasushi Okawa 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited

Claims (2)

[Claims] 1. A plurality of pixel electrodes (3) arranged in a matrix on a surface of one side substrate (21) of a pair of opposing insulating substrates (21, 22) and the plurality of pixel electrodes. Each of the pixel electrodes (3) has a plurality of bus lines (2, 11) arranged corresponding to the rows or columns of (3) and is transparent on the other side substrate (22). A black pattern (1) made of a stripe-shaped non-translucent conductive film for light shielding the surroundings of the black pattern (1) corresponding to the bus line (2) in at least one direction and the corresponding bus. The connection ends (8, 9) are arranged at both ends of the line (2) so as to face each other, and the connection ends (8, 9) facing each other can be electrically connected to each other. Liquid crystal display device. 2. The pair of insulating substrates (21, 22) are bonded to each other at the positions of the connection ends (8, 9, 12) facing each other with a sealing agent mixed with an anisotropic conductive material. The liquid crystal display device according to claim 1, wherein: