JP2622174B2 - Matrix type display device - Google Patents

Description

The present invention relates to a matrix type display device used for a reflection type liquid crystal display device and the like.

(Prior Art) A reflective matrix liquid crystal display device is used for a display of a laptop personal computer, a word processor or the like. Active matrix systems are frequently used in these liquid crystal display devices. In an active matrix display device, picture elements arranged in a matrix are selectively driven by scanning lines and signal lines.

FIG. 5 is a schematic plan view of a matrix type display device used in a conventional reflection type matrix type display device. A number of gate bus lines 1 functioning as scanning lines are provided in parallel. A large number of source bus lines 2 functioning as signal lines are provided crossing the gate bus lines 1.
The gate bus line 1 and the source bus line 2 intersect in a non-conductive state via an insulating film. FIG. 2 is a schematic diagram of a rectangular region surrounded by the gate bus wiring 1 and the source bus wiring 2. A TFT 3 is arranged near the intersection of the gate bus line 1 and the source bus line 2. The TFT 3 functions as a switching element, and is connected to the gate bus wiring 1, the source bus wiring 2, and the picture element electrode 5. In the substrate shown in FIG. 5, a region surrounded by a broken line is the display screen 10.

(Problems to be Solved by the Invention) In the display device using the active matrix substrate shown in FIG. 5, in the area where the pixel electrodes 5 of the display screen 10 are arranged in a matrix, the pixel electrodes 5 Metal wirings of the gate bus wiring 1 and the source bus wiring 2 are formed between them. However, in a region other than the region where the pixel electrodes 5 are arranged in a matrix, only one of the gate bus line 1 and the source bus line 2 is formed. Since the density of the metal wiring is different between the region where the pixel electrodes 5 are arranged and the other region,
Two areas with different brightness are generated on the display screen.
Such a difference in brightness is not preferable as a display device.

By the way, in order to display a fine image using an active matrix display device, it is necessary to make the picture elements constituting 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 the gate bus wiring 1 and the source bus wiring 2 increases accordingly. As the total length of the gate bus wiring 1 and the source bus wiring 2 becomes longer, disconnection failures are more likely to occur in these wirings 1 and 2. For example, if a disconnection failure occurs in the source bus wiring 2, no signal voltage is applied beyond the disconnection portion, so that a linear defect occurs on the display screen 10. The line-like defects significantly lower the image quality of the display device, and are a major cause of a decrease in the yield of the display device. In addition, as the size of the display device increases, the total length of these bus lines further increases. When the bus wiring becomes long as described above, it becomes increasingly difficult to manufacture a bus wiring without disconnection failure.

The present invention solves such a problem,
An object of the present invention is to provide a matrix type display device which can obtain a display screen with uniform brightness and can correct a disconnection defect.

(Means for Solving the Problems) A matrix type display device according to the present invention includes a pair of insulating substrates, picture element electrodes arranged in a matrix on one of the inner surfaces of the pair of substrates, A plurality of scanning bus wirings arranged at equal intervals along each row of the pixel electrodes on one substrate inner surface, and at equal intervals along each column of the pixel electrodes on the one substrate inner surface. A plurality of signal bus wirings arranged, an internal area of the inner surface of the one substrate where an intersection of the scanning bus wiring and the signal bus wiring exists, and a scanning bus wiring and a signal bus facing each other with the internal area interposed therebetween. An external region where one of the wirings is present is a matrix type display device having a structure corresponding to a display screen, and intersects one of the scanning bus wiring and the signal bus wiring via an insulating film in the external region. And the plurality of scanning bus lines and signals A plurality of pseudo wirings arranged so as to be parallel to each other at the same interval as the other of the wirings, the pseudo wirings being electrically connected to the broken bus wirings and having the wirings; Is configured to be applied.

 Thereby, the above object is achieved.

(Function) According to the present invention, an internal area having a plurality of signal bus wirings and a plurality of scanning bus wirings which intersect each other is provided, and an internal area where an intersection of the signal bus wirings and the scanning bus wirings is located is opposed to the internal area. In the matrix type display device corresponding to the display screen, at least one pseudo wiring is provided in the external region where either of the two bus wirings is located, by the one of the two bus wirings and the insulating film. , The bus wiring intersecting with the pseudo wiring can be used to repair a display defect due to the disconnection using the pseudo wiring.

In addition, the pseudo wiring arranged in the external region is arranged so as to be parallel to the other of the two bus wirings, and furthermore, the pseudo wiring is arranged in a wiring group including the pseudo wiring and a bus wiring parallel thereto. Since the arrangement interval is the same problem, the internal area of the substrate corresponding to the display screen, that is, the area where both the scanning bus wiring and the signal bus wiring are located, and the external area on both sides thereof, that is, which of the two bus wirings It is possible to eliminate the difference in the existing density of the metal layer constituting the wiring between the region where only the metal layer exists and the region where only the metal layer exists. This allows
It is possible to avoid a portion having different brightness on a display screen due to a difference in the density of the metal layer on the substrate.

(Example) First, the basic configuration and principle of the present invention will be described.

In the matrix type display device of the present invention, an internal region on the substrate where both a signal bus wiring (hereinafter, also referred to as a signal line) and a scanning bus wiring (hereinafter, also referred to as a scanning line) exist, and a region outside the internal region. And an external area where only one of the two bus lines exists corresponds to the display screen.

The matrix type display device intersects one of the scanning bus wiring and the signal bus wiring with at least one layer of an insulating film in the external region, and intersects with the other of the scanning bus wiring and the signal bus wiring. It has at least one pseudo wiring arranged so as to be parallel.

For example, in the matrix type display device of the present invention, pseudo scanning lines (pseudo wirings) are provided in parallel on both outer sides of the scanning line columns. The intervals between the pseudo scanning lines and the intervals between the pseudo scanning lines are set to be the same as the intervals between the scanning lines. Similarly, pseudo signal lines are provided in parallel on both outer sides of the signal line column. The distance between the pseudo signal lines (pseudo wiring) and the signal lines, the distance between the pseudo signal lines, and the distance between the signal lines are set to be the same. As described above, in the matrix type display device of the present invention, the metal wirings are arranged at the same intervals as the scanning lines and the signal lines also in the region other than the region where the pixel electrodes are arranged in a matrix. As a result, there is no difference in screen brightness between the region where the pixel electrodes are arranged and the other region.

Further, in the matrix type display device of the present invention, the pseudo scanning line intersects with the column of the signal line via at least one insulating film. Similarly, the pseudo signal line intersects with the row of the scanning line via at least one insulating film. The pseudo scan line provided on one side of the row of scan lines is paired with the pseudo scan line on the other side parallel to the row of scan lines, and is provided on one side of the row of signal lines. The pseudo signal line can be configured to form a pair with the pseudo signal line on the other side parallel to the signal line column. The two pseudo scanning lines forming a pair and the two pseudo signal lines forming a pair form a rectangle, and may be electrically connected to each other at intersections. With the configuration in which the pseudo scanning lines and the pseudo signal lines are connected in advance, even if a disconnection failure occurs in any of the scanning lines and the signal lines, the disconnection failure can be corrected.

This disconnection defect is corrected by connecting the scanning line and the pseudo signal line, or by connecting the signal line and the pseudo scanning line. That is, when a disconnection failure occurs in a scanning line, the defective scanning line and two pseudo signal lines forming a pair are connected at both ends of the defective scanning line. When a disconnection failure occurs in the signal line, the defective signal line is connected to two pairs of pseudo scanning lines at both ends of the failure signal line. The defective scanning line and the pseudo signal line, and the defective signal line and the pseudo scanning line are connected by irradiating each intersection with light energy such as laser light. By performing the connection in this manner, the disconnection defect is corrected.

In the matrix-type display device of the present invention, both ends of the two pseudo scanning lines forming a pair can be drawn out of the substrate and electrically connected to each other or arranged so as to be connectable. With such a configuration, even if a disconnection failure occurs in the signal line, it can be easily corrected. This disconnection defect is corrected by connecting the pseudo scanning line and the defective signal line by laser beam irradiation, as described above. Similarly, both ends of two pseudo signal lines forming a pair may be drawn out of the substrate and electrically connected to each other, or may be arranged so as to be connectable. With this configuration, a disconnection defect occurring in the scanning line can be corrected.

 Hereinafter, examples of the present invention will be described.

FIG. 1 is a plan view for explaining a matrix type display device according to one embodiment of the present invention, and shows a schematic configuration of an active matrix substrate constituting the display device.
The substrate shown in FIG. 1 is used for a reflective display device. A number of gate bus lines 1 functioning as scanning lines are provided in parallel. An insulating film 8 described later is formed on the gate bus wiring 1.
Is formed on the entire surface of the substrate. On the gate bus line 1, a number of source bus lines 2 functioning as signal lines are provided.
Intersect with each other via the insulating film 8.

FIG. 2 is a schematic diagram of a rectangular region surrounded by the gate bus wiring 1 and the source bus wiring 2. A TFT 3 is arranged near the intersection of the gate bus line 1 and the source bus line 2. The TFT 3 functions as a switching element, and is connected to the gate bus wiring 1, the source bus wiring 2, and the picture element electrode 5. A region surrounded by a broken line is the display screen 10 as shown in FIG.

Pseudo wirings 26 and 27 are provided on the outer periphery of a rectangular area where the gate bus wiring 1 and the source bus wiring 2 intersect. The pseudo wiring 26 has a rectangular shape by the pseudo scanning lines 6a and 6b and the pseudo signal lines 16a and 16b. The pseudo wiring 27 is provided further on the outer periphery of the pseudo wiring 26, and the pseudo scanning line
7a and 7b and the pseudo signal lines 17a and 17b form a rectangle.

The distance between the outermost gate bus wiring 1a and the pseudo scanning line 6a in the column of the gate bus wiring 1, and the distance between the pseudo scanning line 6a
The distance from the gate bus line 1 is equal to the distance between the gate bus lines 1. Also, the distance between the outermost gate bus wiring 1b located on the opposite side of the gate bus wiring 1a and the pseudo scanning line 6b,
The interval between the pseudo scanning lines 6b and 7b is also equal to the interval between the columns of the gate bus line 1. Similarly, the interval between the outermost source bus line 2a of the column of the source bus lines 2 and the pseudo signal line 16a, and the interval between the pseudo signal lines 16a and 17a are equal to the interval between the columns of the source bus line 2. Have been.
Also, the interval between the outermost source bus line 2b located on the opposite side of the source bus line 2a and the pseudo signal line 16b, and the interval between the pseudo signal lines 16b and 17b are equal to the column interval of the source bus line 2. Have been.

In this embodiment, the pseudo scanning lines 6a, 6b, 7a and 7b are formed simultaneously with the gate bus wiring 1. Therefore, the pseudo scan line
6a, 6b, 7a and 7b are formed of the same material as the gate bus wiring 1. Also, pseudo signal lines 16a, 16b, 17a, and 17b
Are formed simultaneously with the source bus wiring 2. Therefore, the pseudo signal lines 16a, 16b, 17a, and 17b are formed of the same material as the source bus line 2.

In the present embodiment, the above-described insulating film 8 is removed at a portion where the pseudo scanning lines 6a and 6b and the pseudo signal lines 16a and 16b intersect, so that the pseudo scanning lines 6a and the pseudo signal lines 16a and 16b
The dummy scanning line 6b and the dummy signal lines 16a and 16b are electrically connected. Similarly, pseudo scan lines 7a and 7b,
In the part where the pseudo signal lines 17a and 17b intersect,
The aforementioned insulating film 8 is removed, and the pseudo scanning line 7a and the pseudo signal line
17a and 17b, and the pseudo scan line 7b and the pseudo signal line 17
a and 17b are electrically connected.

In this embodiment, on both outer sides of the column of the gate bus line 1, pseudo scanning lines parallel to the column of the gate bus line 1 at the same interval are provided.
The gate bus line 1 is formed of the same material. Similarly, on both outer sides of the column of the source bus lines 2, pseudo signal lines parallel to the columns of the source bus lines 2 at the same intervals are formed of the same material as the source bus lines 2. In this manner, the pseudo wiring is provided outside the region where the pixel electrodes 5 are provided in a matrix.
With the provision of 26 and 27, there is no difference in screen brightness between the region where the pixel electrodes 5 are arranged and the other region.

In the present embodiment, the disconnection failure occurring in the gate bus wiring 1 and the source bus wiring 2 can be corrected by using the pseudo wirings 26 and 27. As an example, a case where a disconnection portion 12 occurs in the source bus wiring 2c as shown in FIG. In such a case, the defective source bus wiring 2c and the pseudo scanning lines 6a and 6b are electrically connected at intersections 11a and 11b, respectively.

3 (a) and 3 (b) are cross-sectional views along the pseudo scanning line 6a at the intersection 11a. The pseudo scanning line 6a is formed on the glass substrate 13, and the above-described insulating film 8 is formed on the entire surface of the pseudo scanning line 6a. The source bus wiring 2c intersects the pseudo scanning line 6a via the insulating film 8. Pseudo scanning line 6a
The defective source bus line 2c is connected to the defective source bus line 2c by irradiating the position shown by the arrow 14 with a laser beam. The insulation of the insulating film 8 is broken by the laser beam irradiation, and the metal of the pseudo scanning line 6a and the metal of the defective source bus wiring 2c are melted and electrically connected to each other. Similarly, also at the intersection 11b, the pseudo scanning line 6b and the defective source bus wiring 2c are connected by laser beam irradiation. Since the pseudo scanning lines 6a and 6b are electrically connected by the pseudo signal lines 16a and 16b, the defective source bus wiring 2c
Both sides of the disconnection portion 12 are electrically connected via the pseudo scanning lines 6a and 6b and the pseudo signal lines 16a and 16b.

In the present embodiment, a disconnection defect occurring in the gate bus wiring 1 can also be corrected. In this case, the defective gate bus wiring and the pseudo signal lines 16a and 16b are electrically connected by laser light irradiation. Further, in the above description, an example in which the correction is performed using the pseudo wiring 26 is shown, but the correction can be similarly performed using the pseudo wiring 27. Further, if the pseudo wires 26 and 27 are used, disconnection defects occurring in two different gate bus wires 1 and source bus wires 2 can be corrected.

FIG. 4 is a plan view for explaining a matrix type display device according to another embodiment of the present invention, and shows the schematic configuration of an active matrix substrate constituting the display device. A number of gate bus lines 1 functioning as scanning lines are provided in parallel. Crossing the gate bus wiring 1,
A large number of source bus lines 2 functioning as signal lines are provided. The gate bus line 1 and the source bus line 2 intersect via the insulating film 8 in a non-conductive state. A schematic diagram of a rectangular region surrounded by the gate bus wiring 1 and the source bus wiring 2 is the same as that in FIG. 2 described above. A TFT 3 is arranged near the intersection of the gate bus line 1 and the source bus line 2. TFT3 functions as a switching element and TF
The gate electrode of T3 is connected to the gate bus line 1, the source electrode is connected to the source bus line 2, and the drain electrode is connected to the pixel electrode 5. An area surrounded by a broken line is the display screen 10 as shown in FIG.

Pseudo scanning lines 6a, 7a, 6b and 7b are formed parallel to both outer sides of the column of the gate bus wiring 1. Pseudo scan line 6a,
7a, 6b and 7b are formed at the same time as the gate bus wiring 1, and are therefore formed of the same material as the gate bus wiring 1.
The distance between the outermost gate bus line 1a of the column of the gate bus line 1 and the pseudo scanning line 6a, and the pseudo scanning lines 6a and 7a
Are made equal to the intervals between the columns of the gate bus lines 1. Further, the interval between the outermost gate bus line 1b located on the opposite side of the gate bus line 1a and the pseudo scanning line 6b, and the interval between the pseudo scanning lines 6b and 7b are also equal to the interval between the columns of the gate bus line 1. Have been.

Both ends of each of the pseudo scanning lines 6a, 7a, 6b and 7b are parallel to the source bus wiring 2 and are drawn out of the substrate. The ends of the pseudo scanning lines 6a drawn out of the substrate are connected to the ends of the pseudo scanning lines 6b drawn out of the substrate. Similarly, the end of the pseudo scanning line 7a drawn out of the substrate is arranged to be connectable to the end of the pseudo scanning line 7b.

On both outer sides of the column of the source bus wiring 2, pseudo signal lines 16
a, 17a, 16b and 17b are formed. Pseudo signal line 16
a, 17a, 16b and 17b are formed at the same time as the source bus wiring 2, and are therefore formed of the same material as the source bus wiring 2. The interval between the outermost source bus line 2a and the pseudo signal line 16a and the interval between the pseudo signal lines 16a and 17a in the column of the source bus line 2 are made equal to the interval between the columns of the source bus line 2. ing. Also, the interval between the outermost source bus line 2b located on the opposite side of the source bus line 2a and the pseudo signal line 16b, and the interval between the pseudo signal lines 16b and 17b are equal to the column interval of the source bus line 2. Have been.
In this embodiment, the pseudo signal lines 16a, 17a, 16b and 17b are independent of each other and are not connected to other wirings.

Also in this embodiment, pseudo scanning lines that are parallel to the columns of the gate bus lines 1 at the same intervals are provided outside the columns of the gate bus lines 1 using the same material as the gate bus lines 1. Similarly,
Outside the column of the source bus lines 2, pseudo signal lines parallel to the columns of the source bus lines 2 at the same intervals are provided.
It is provided with the same material as. With such a configuration,
There is no difference in screen brightness between the region where the pixel electrodes 5 are arranged and the other region.

As shown in FIG. 4, when the disconnection portion 12 is generated in the source bus wiring 2c, the defective source bus wiring 2c and the pseudo scanning lines 6a and 6b are connected to each other similarly to the embodiment of FIG. Are connected by laser light irradiation at intersections 11a and 11b. Pseudo scanning lines 6a and 6b connected to defective source bus wiring 2c
Are electrically connected to each other at a portion drawn out of the substrate. As a result, the disconnection portion 12 of the defective source bus line 2c is
Are electrically connected via pseudo scanning lines 6a and 6b.

In the present embodiment, the pseudo signal lines 16a, 17a, 16b, and 17b are independent of each other and are not connected to other wirings, so that a disconnection defect occurring in the gate bus wiring 1 cannot be corrected. In the above description, an example in which the correction is performed using the pseudo scanning lines 6a and 6b is described, but the correction can be performed using the pseudo scanning lines 7a and 7b. Further, by using the pseudo scanning lines 6a and 6b and the pseudo scanning lines 7a and 7b, it is possible to correct a disconnection defect occurring in two different gate bus lines 1.

(Effects of the Invention) As described above, according to the present invention, an internal area where both a signal bus wiring and a scanning bus wiring are present, and an external area where only one of the two bus wirings is opposed to the internal area. In a matrix type display device corresponding to a display screen, at least one pseudo wiring intersects one of the bus wirings via at least one insulating film in the external region, and Place it parallel to the other side of the wiring,
The pseudo wiring is electrically connected to the broken bus wiring, and a signal corresponding to the broken bus wiring is applied, thereby improving the manufacturing yield of the display device and reducing the cost. There is an effect that can contribute to.

In addition, the pseudo wiring arranged in the external area is:
Since the adjacent wirings in the wiring group including the pseudo wiring and the bus wiring parallel to the dummy wiring are arranged in parallel with the other of the two bus wirings, they are arranged at the same interval. There is an effect that a display screen with uniform brightness can be obtained in the internal region where the elementary electrodes are arranged and the external region around the internal region, and the image quality can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of an active matrix substrate used in one embodiment of a matrix type display device of the present invention.
The figure is a schematic view of a rectangular area surrounded by the gate bus wiring and the source bus wiring of FIGS. 1, 4 and 5, and FIG. 3 (a) is at the intersection of the pseudo scanning line and the source bus wiring. FIG. 3B is a cross-sectional view taken along a pseudo-scanning line, FIG. 3B is a view showing a state where the pseudo-scanning line and a source bus wiring are connected by laser beam irradiation, and FIG. 4 is another embodiment of the present invention. FIG. 5 is a schematic plan view of a conventional active matrix substrate. 1 ... gate bus wiring, 2 ... source bus wiring, 3 ...
TFT, 5 ... picture element electrode, 6a, 6b, 7a, 7b ... pseudo scan line, 8
... insulating film, 10 ... display screen, 11a, 11b ... intersection, 12 ...
… Disconnection part, 16a, 16b, 17a, 17b …… Pseudo signal line, 26,27 ……
Pseudo wiring.

Claims (1)

(57) [Claims] 1. A pair of insulating substrates, picture element electrodes arranged in a matrix on the inner surface of one of the pair of substrates, and one row of the picture element electrodes on the inner surface of the one substrate. A plurality of scanning bus wirings arranged at equal intervals along the plurality of signal bus wirings arranged at equal intervals along each column of the picture element electrodes on the inner surface of the one substrate. The internal area of the substrate inner surface where the intersection of the scanning bus wiring and the signal bus wiring is present, and the external area facing either side of the internal area and having either the scanning bus wiring or the signal bus wiring are on the display screen. A matrix type display device having a structure corresponding to the above, wherein, in the external region, one of the scanning bus wiring and the signal bus wiring intersects via an insulating film, and the plurality of scanning bus wirings and signal bus wirings Plural arranged at the same interval and parallel to the other Wherein the pseudo wiring is electrically connected to the broken bus wiring and a signal corresponding to the bus wiring is applied. .