JPH0323425A - Matrix type display device - Google Patents

Abstract

PURPOSE:To correct a disconnection part and to prevent the load capacity, electric resistance, and noise of wiring after the correction from increasing by providing spare wiring which crosses scanning lines and signal lines across and insulating film on both end parts of columns of the scanning lines and signal lines and leading its one end out of a display electrode substrate so that it can be connected. CONSTITUTION:The spare wiring 3 which crosses some of scanning or signal lines in an column and an insulating film is provided at both end parts of at least one of columns of the scanning lines 1 and signal lines 2, and one end is led out of the display electrode substrate and arranged so that it can be connected mutually. If bus wire 1 or 2 crossing the spare wiring is broken to become defective bus wiring, the defective bus wiring and spare wiring 3 are connected electrically to two intersection parts 4a and 4b of the defective bus wiring and two spare wiring parts 3. Further, the two spare wiring parts 3 are connected electrically outside the display electrode substrate where they can be connected. Consequently, the defective wiring is corrected and the load capacity and electric resistance of the whole bus wiring after the correction never increase.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a matrix type display device having a function of correcting disconnection of bus wiring.

(Prior Art) A matrix type display device using liquid crystal or the like is attracting attention as an image display device to replace a CRT.

In order to display fine images using a matrix type display device, it is necessary to make the size of the picture elements that make up the matrix very small and to use a very large number of picture elements. As the number of picture elements increases, the total length of bus wiring that functions as scanning lines and signal lines also increases. As the total length of the bus wiring increases, disconnection defects are more likely to occur in the bus wiring.

Moreover, as display devices become larger, the total length of bus wiring becomes longer, and it becomes increasingly difficult to manufacture bus wiring without disconnection defects.

(Problems to be Solved by the Invention) A matrix display device has been developed that has a function of correcting disconnection defects in bus wiring. FIG. 4 shows an example of a circuit diagram of a display electrode substrate used in the display device. A large number of source bus lines 1 are provided in parallel, orthogonal to a large number of gate bus lines 2 that are parallel to each other in one direction. The gate bus wiring 2 and the source bus wiring 1 intersect with each other with an insulating film interposed therebetween in a non-conducting state. Each rectangular area surrounded by the gate bus wiring 2 and the source bus wiring l has a pixel electric field l2.
are provided respectively, and a liquid crystal is sealed between the picture element storage I2 and the counter electrode to form a crystal cell 16.

Each picture element electrode l2 has a TFT as a switching element.
(Dinghin Film Transistor) 1
l is connected. The gate electrode l3 and source electrode l4 of TFTII are connected to the gate bus line 2 and the source bus line 11, respectively. The drain electrode 15 of TFTII is connected to the picture element electrode 12. A preliminary wiring 3 is provided around the outer periphery of a region where a large number of picture elements are formed. Preliminary wiring 3 is each gate bus wiring 1i12
and intersect with the source bus line 1 via an insulating film in a non-conductive state.

In a display electrode substrate having such a circuit, if a disconnection defect occurs in the first bus wiring 1, for example, the defect can be corrected using the spare wiring 3. If a disconnection 4 occurs in one source bus wiring l as shown in FIG. 4, the defective source bus wiring 1 that has the disconnection 4
The defective source bus line 1 and the spare line 3 are electrically connected at intersections 4a and 4b that intersect with the spare line 3 at both ends of the line. By connecting at two locations in this manner, the portions on both sides of the disconnection portion 4 of the defective source bus wiring 1 are electrically connected via the preliminary wiring 3.

However, when correction is performed in this manner, the following problems occur.

First of all, there is the issue of load capacity. Preliminary wiring 3
The load capacity pan C2 of the source bus wiring l (hereinafter referred to as "modified source bus wiring") to which is connected is the load capacity ffi C e of the normal source bus wiring l, and the load capacity ffi C + of the preliminary wiring 3. The value is the sum of That is, C2=
It becomes Ce+CI. The length of the preliminary wiring 3 is approximately equal to the total length of the two gate bus wirings 2 and the two source bus wirings 1, and therefore has a much larger value than the load capacitance ffiC+IiC8. The frl of the driver IC that supplies the signal to the picture element electrode l2 via the source bus wiring 1 is
Since it is designed by determining the load capacitance C8 of the normal source bus line, the capacity is insufficient to drive the picture element electrode l2 via the modified source bus wiring having a large load capacitance c2. Therefore, the picture element formed by the picture element electrode 12 connected to the corrected source bus wiring has a different display state from the picture element formed by the picture element electrode 12 connected to the normal source bus wiring l. becomes. Therefore, even if the repair is performed using the preliminary wiring 3 as described above, the disconnection portion 4 cannot be completely repaired.

The second problem is signal delay.

Assuming that a signal is supplied to the corrected source bus wiring from the end closer to the intersection 4b, the signal is supplied to the part of the corrected source bus wiring from the disconnection part 4 to the intersection 4a via the preliminary wiring 3. It will be done.

The signal is transmitted over a longer distance than other normal source bus lines L'X1 until it reaches the intersection 4a. In this way, the entire length of the corrected source bus wiring becomes longer than the normal source bus wiring, and the electrical resistance increases, resulting in signal delays. A picture element formed by the picture element electrode l2 whose signal is greatly delayed has a display state different from a picture element formed by the picture element electrode 12 connected to the other normal source bus line l. Therefore, even if the repair is performed using the preliminary wiring 3 as described above, the disconnection portion 4 cannot be completely repaired. .

The third problem is signal noise.

Since the preliminary wiring 3 intersects with all the gate bus wirings 2 and source bus wirings 1, the modified source bus markings connected to this preliminary wiring 3 will be able to handle the signals of the many intersecting bus wirings. to be influenced. The influence of these signals is weighted on the preliminary wiring 3 and appears as noise. This noise is much larger than the noise of a normal source bus wiring l that does not have any intersections with other source bus wiring l.
The picture element formed by the picture element electrode l2 connected to the modified source path wiring may have a different display state from the picture element formed by the other normal picture element 74 electrode l2. In such a case, even if the repair using the preliminary wiring 3 is performed as described above, the disconnection portion 4 cannot be completely repaired.

All of the above problems arise as display devices become larger.
noticeable. As mentioned above, as the size of the display device increases, disconnection defects become more likely to occur, so the larger the display device, the greater the need to solve the above-mentioned problems.

The present invention solves the above-mentioned problems, and an object of the present invention is to have a function of correcting a disconnection, and even if the disconnection is corrected, the load capacity, electrical resistance, and It is an object of the present invention to provide a matrix type display device in which noise hardly increases.

(Means for Solving the Problems) A matrix type display device of the present invention includes picture element electrodes arranged in a matrix, and scanning lines arranged vertically and horizontally in rows in one direction between the picture element electrodes. A matrix type display device including a display electrode substrate having a line and a signal line, at each of both ends of at least one column of the scanning line and the signal line. comprising a preliminary wiring that intersects with at least a part of the lines through an insulating film,
One end of each of the preliminary wirings is drawn out to the outside of the display electrode substrate and arranged so as to be connectable to each other, thereby achieving the above object.

(Function) In the matrix type display device of the present invention, among the bus wiring consisting of scanning lines and signal lines formed on the display electrode substrate,
At each of both ends of at least one part of the bus wiring, the preliminary wiring intersects with an insulating film interposed therebetween. Each preliminary wiring is drawn out to the outside of the display electrode substrate, such as a circuit board, by a wiring with low load capacity and electrical resistance, or as a jumper wire, and arranged so that it can be connected later.

If a break occurs in any of the bus wirings that the spare wiring intersects with, resulting in a defective bus wiring, the defective bus wiring and the two
The defective bus wiring and the spare wiring are electrically connected at each of the two intersections with the two spare wirings. Furthermore,
The two preliminary wirings are electrically connected at a connectable portion outside the display electrode substrate. Both sides of the bus wiring that has been disconnected in this way are electrically connected outside the display electrode substrate via the spare wiring, and the defective bus wiring is repaired.

In the display device of the present invention, the preliminary wiring on the display electrode substrate is not formed on the entire outer periphery of the substrate as in the conventional example described above, but is formed with the minimum necessary length. Therefore, the load capacitance and electrical resistance of the entire bus wiring modified using the spare wiring do not become extremely large as in the conventional example described above. Therefore, the driver IC will not have insufficient capacity, and the signal will not be delayed. Furthermore, in the display device of the present invention, since the number of bus wires that the preliminary wire intersects can be reduced, noise received from signals of these intersecting bus wires can be reduced.

(Example gA+) The present invention will be described below with reference to Examples. FIG. 1 shows a circuit diagram of an example of an active matrix substrate used in a matrix type display device of the present invention.

Orthogonally to a large number of gate bus lines 2 parallel to one direction,
A large number of source bus lines 1 are provided in parallel. The source path wiring 1 consists of two sets of source bus wirings 1a and lb, and the source bus wirings 1a and 1b are connected to different driver ICs, respectively. The gate bus line 2 and the source bus line 1 intersect with each other with an insulating film interposed therebetween in a non-conducting state.

A picture element electrode l2 is provided in each rectangular area surrounded by the gate bus wiring 2 and the source bus wiring 1, liquid crystal is sealed between the picture element electrode l2 and the 74 opposing poles, and a liquid crystal cell 16 is formed. It is formed. A TFTll is connected to each picture element electrode l2 as a switching element. TFT
The gate electrode l3 and source electrode 14 of II are connected to the gate bus line 2 and source bus line 1, respectively.

The drain electrode l5 of TFTII is connected to the picture element electrode 12. Preliminary wirings 3a and 3b intersect at both ends of the bus wiring 1 with an insulating film interposed therebetween. The preliminary wires 3a and 3b are each connected to a wire outside the substrate without intersecting the gate bus wire 2.

FIG. 2 shows a plan view of an example of a driver film connected to an active matrix substrate having the circuit shown in FIG. 1. A driver IC 8 is provided on the driver film 7, and a source bus connection line 9 extending from the driver IC 8 is connected to the source bus wiring 1a. A preliminary wiring 10 on the film is provided in parallel to the source bus connection line 9.

One end 10a of the on-film auxiliary wiring 10 is connected to the auxiliary wiring 3a on the active matrix substrate. The other end 10b of the on-film preliminary wiring 10 is connected to a connection wiring led onto the circuit board.

Another set of source bus wiring 1b and preliminary wiring 13b on the active matrix substrate of FIG. 1 are connected to another driver film similar to that shown in FIG.
The preliminary wiring on the film to which b is connected is further connected to the connection wiring led on the circuit board. On the above circuit board, two connection wirings connected to the two preliminary wirings 3a and 3b via the preliminary wiring on the film are arranged so that they can be connected to each other later.

A method of correcting a disconnection failure occurring in the source bus wiring l of the display device of this embodiment will be described below. If a disconnection 4 occurs in the source bus wiring II) as shown in FIG.
The defective source bus wiring tb and the preliminary wiring 1i3a are electrically connected at the intersection portions 4a which intersect with the preliminary wiring 3a at both ends of the defective source bus wiring 1b where the disconnection portion 4 has occurred.

Similarly, the defective bus wiring glb and the spare wiring 3b are electrically connected at the intersection 4b that intersects with the spare wiring 113b. Furthermore, on the aforementioned circuit board, two connection wires connected to the preliminary wires 3a and 3b are electrically connected. By making electrical connections at three locations in this manner, both ends of the disconnected portion 4 of the source bus wiring 1b are electrically connected via the connection wiring outside the substrate.

The load capacitance and electrical resistance of the entire source bus wiring whose disconnection has been corrected in this way does not become extremely large as in the prior art example described above. Therefore, the driver IC 8 does not have insufficient capacity, and no signal delay occurs. Also,
In the display device of the present invention, the number of bus wires that intersect with the spare wires can be reduced, so noise from these intersecting bus wires is reduced.

FIG. 3 shows a circuit diagram of another embodiment of the present invention.

In FIG. 3, for the sake of simplicity, gate bus wiring, TFT1 picture element electrodes, etc. are omitted, and only source bus wiring and spare wiring are shown. In this example, the source bus wiring l is 41I
The source bus wiring of 1 is divided into 1a% lbs IC% and 1d. Source bus lines 1a, lb, lc, and 1d are connected to different drivers rc, respectively.

Preliminary wiring 3a is provided at both ends of the bus wiring 1a and lc.
and 3c intersect with each other via an insulating film.

Similarly, preliminary wires 3b and 3d intersect at both ends of source bus wires 1b and ld with an insulating film interposed therebetween. The source bus wiring 111a and the spare wiring 3a are connected to the source bus connection line on the driver film and the spare wiring on the film as shown in FIG. connected to wiring. Similarly, the source bus wiring 1c and the spare wiring vA3c are connected to the source bus connection line on the driver film and the spare wiring on the film, and the spare wiring on the film is further connected to the connection wiring led on the circuit board. ing. The connection wiring led on the circuit board is connected to the above-mentioned preliminary wiring 113a via the preliminary wiring on the film, and
It is arranged so that it can be connected later. Similarly, the preliminary wires 3b and 3d are also connected to connection wires arranged on the circuit board so that they can be connected to each other.

In this example, when a disconnection 4 occurs in the source bus wiring 1a, the defective source bus wiring 1a and the two spare wiring i13a are connected to each other at both ends of the defective source bus wiring 1a where the disconnection 4 has occurred. and 3c are connected. That is, the defective source bus wiring 1a and the spare wiring 3a are electrically connected at the intersection 4a, and the defective source bus wiring 1a and the spare wiring 1i
3c are electrically connected at the intersection 4C. Furthermore, on the aforementioned circuit board, two connection wires connected to the preliminary wires 3a and 3C are electrically connected. By making electrical connections at three locations in this way, both ends of the disconnected portion 4 of the source bus wiring 1a are connected to the preliminary wiring 3a and 3c.
, and are electrically connected via a circuit external to the display electrode substrate.

In the above embodiments, only the structure for correcting a disconnection defect in the source bus wiring 1 of the present invention has been described, but the present invention has a structure for correcting a disconnection defect occurring in the gate bus interconnection 2. You can also do that.

In order to obtain a configuration for correcting a disconnection defect in the gate bus wiring 2, the spare wiring is arranged to intersect with the gate bus wiring 2 with an insulating film interposed therebetween. Furthermore, the display device of the present invention has a disconnection correction function of the source bus wiring and a gate bus wiring 2.
It is also possible to have a configuration having a disconnection correction function.

In this embodiment, only an active matrix type display device has been described, but the present invention can also be applied to other types of display devices.

(Effects of the Invention) The matrix type display device of the present invention has a function of correcting a disconnected part of a bus wiring, and the load capacity, electrical resistance, and noise of the corrected wiring hardly increase.Therefore,
Pixel defects can be reliably corrected, the yield of display devices can be improved, and the cost of display devices can be reduced.

4. of. N:8 FIG. 1 is a circuit diagram of an example of an active matrix substrate used in a matrix type display device of the present invention, and FIG.
Top view of the driver film connected to the board shown in Figure 3.
The figure is a circuit diagram of source bus wiring and spare wiring according to another embodiment of the present invention, and FIG. 4 is a circuit diagram showing an improved example of an active matrix board having a function of correcting disconnection defects.

1, la, lb, lc, ld... source bus wiring, 2... gate bus wiring, 3a, 3b, 3c, 3d-
Preliminary wiring, 4...disconnection part, 4a, 4b...crossing part,
7... Driver film, 8... Driver IC, 9
-... Source bus connection line, 10... Preliminary wiring on film, 1l... TFT, 12... Picture element electrode.

that's all

Claims (1)

[Claims] 1. A matrix type including a display electrode substrate having picture element electrodes arranged in a matrix, and scanning lines and signal lines arranged vertically and horizontally in rows in one direction between the picture element electrodes. In the display device, each of the ends of at least one of the scanning lines and the signal lines intersects with at least some lines in the one column via an insulating film. A matrix type display device comprising preliminary wiring, one end of each of the preliminary wiring being drawn out to the outside of the display electrode substrate, and arranged so as to be connectable to each other.