JPH0416930A - Active matrix type display device - Google Patents

Abstract

PURPOSE:To correct a pixel defect unobtrusively in a state where a display device is assembled even when the pixel defect due to the defect of a switching element occurs by providing a conductive layer superimposed on the lower side of a signal line and a pixel electrode holding insulating film therebetween, and a conductive piece formed between the pixel electrode and the insulating film. CONSTITUTION:When a TFT is defective or a weak leakage current occurs between a source bus line 23 and the pixel electrode 41, the pixel defect occurs. In such a case, the source bus line 23, the conductive layer 34, and the conductive piece 35 are connected electrically with each other by irradiating the superposition area of the source bus line 23 with the conductive layer 34, and the superposition area 62 of the conductive layer 34 with the conductive piece 35 with light energy first. Since the conductive piece 35 is connected electrically to the pixel electrode 41, it follows that the pixel electrode 41 is connected electrically to the source bus line 23. In such a manner, it is possible to correct the pixel defect unobtrusively in a state where the display device capable of easily detecting the pixel defect is assembled.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a display device that performs display by applying a drive signal to a display pixel electrode via a switching element, and particularly relates to a display device that performs display by applying a drive signal to a display pixel electrode via a switching element. The present invention relates to an active matrix drive type display device that is arranged in a grid pattern and performs high-density display.

(Prior Art) Conventionally, in liquid crystal display devices, EL display devices, plasma display devices, etc., display patterns are formed on the screen by selectively driving pixel electrodes arranged in a matrix. . A voltage is applied between a selected picture element electrode and a counter electrode facing the selected picture element electrode, and optical modulation of a display medium such as a liquid crystal interposed between these electrodes is performed. This optical modulation is visually recognized as a display pattern. As a method for driving picture element electrodes, an active matrix driving method is known in which individual independent picture element electrodes are arranged and a switching element is connected to each of the picture element electrodes and driven.

As a switching element for selectively driving the picture element electrode, T
FT (four-film transistor) element, MIM (metal-insulating layer-metal) element, MOS transistor element, diode,
Barista etc. are generally known. The active matrix drive method allows for high contrast display.
It has been put to practical use in LCD televisions, word processing sensors, computer terminal display devices, etc.

FIG. 12 shows a plan view of an active matrix substrate used in a conventional active matrix display device. In the substrate shown in FIG. 12, source bus lines 23 are arranged perpendicularly to gate bus lines 21 arranged parallel to each other. A picture element electrode 41 is arranged in each rectangular area surrounded by two gate bus lines 21 and two source bus lines 23. A TFT 31 functioning as a switching element is formed on a gate bus branch line 22 branched from the gate bus wiring 21 . A part of the gate bus branch line 22 functions as a gate electrode of the TFT 31. TF
The drain electrode of T31 is electrically connected to the picture element electrode 41. The source electrode of TFT31 is source bus wiring 2
Connected to 3.

(Problem to be solved by the invention) When performing high-density display using such a display device,
It is necessary to arrange a very large number of picture element electrodes 41 and TFTs 31. However, the TFT 31 may be formed as a malfunctioning element at the time it is manufactured on the substrate.

A picture element electrode connected to such a defective element is recognized as a point defect that does not contribute to display. Point defects significantly impair the image quality of display devices and greatly reduce product yield.

There are two main causes of point defects.

One is a defect (hereinafter referred to as "ON defect") that occurs because the picture element electrode is not sufficiently charged during the time when the picture element electrode is selected by the scanning signal. The other one is a defect in which the charge of the charged picture element electrode leaks during a non-selection time (hereinafter referred to as an "off defect").

The ON failure is caused by a TPT failure. Off failure is TPT
In some cases, this is caused by electrical leakage between the picture element electrode and the bus wiring, and in other cases, it is caused by electrical leakage between the picture element electrode and the bus wiring. No matter which defect occurs, a point defect will occur because a necessary voltage is not applied between the picture element electrode and the counter electrode. Such defects appear as bright spots in the normally white mode where the light transmittance is maximum when the voltage applied between the picture element electrode and the counter electrode is Ov; In normally black mode, where the light transmittance is the lowest, it appears as a black spot.

Such defects can be corrected by laser trimming or the like. However, this defect correction must be performed at the active matrix substrate stage before the display device is assembled. Although it is easy to detect pixel defects after the display device is assembled, it is extremely difficult to detect pixel defects at the active matrix substrate stage.

In particular, in large display devices with 100,000 to 500,000 or more picture elements, the electrical characteristics of all picture element electrodes are detected to detect defects.
To discover PT, it is necessary to use extremely high-precision measuring equipment. Therefore, the inspection process becomes complicated and mass productivity is hindered.

This results in increased costs. For these reasons, the reality is that in large display devices with a large number of picture elements, it is not possible to correct pixel defects in the substrate using the above-mentioned laser beam.

The present invention solves these problems, and an object of the present invention is to correct the defect so that it is not noticeable when the display device is assembled, even if a pixel defect occurs due to a defective switching element. An object of the present invention is to provide an active matrix type display device that obtains the desired results.

(Means for Solving the Problems) An active matrix display device of the present invention includes a pair of insulating substrates, at least one of which is translucent, and wires arranged vertically and horizontally on one of the pair of substrates. An active matrix display device comprising a scanning line and a signal line, and a picture element electrode connected to the scanning line and the signal line via a switching element, the signal line and the picture element electrode The above-mentioned object is achieved by comprising a conductive layer superimposed below with an insulating film interposed therebetween, and a conductive piece formed between the picture element electrode and the insulating film.

Further, the active matrix display device of the present invention includes a pair of insulating substrates, at least one of which is translucent, and scanning lines and signal lines wired vertically and horizontally on one of the pair of substrates. , a picture element electrode connected to the scanning line and the signal line via a switching element, the active matrix display device comprising: a picture element electrode connected to the scanning line and the signal line through a switching element, the display device being below the signal line and the pair of picture element electrodes adjacent to each other; The above-mentioned object is achieved by comprising a conductive layer superimposed on the electrodes with an insulating film in between, and conductive pieces formed between the pair of picture element electrodes and the insulating film.

Furthermore, the conductive layer may be electrically connected to a scanning line adjacent to the scanning line connected to the picture element electrode, and an anodic oxide film may be formed on the conductive layer. .

Furthermore, an additional capacitance electrode is provided which faces the picture element electrode with the insulating film in between, the conductive layer is electrically connected to the additional capacitance electrode, and an anodic oxide film is provided on the conductive layer. It is also possible to have a configuration in which it is formed.

(Function) In the active matrix display device of the present invention, if an on-failure or an off-failure occurs due to a defective switching element, generation of a weak leakage current between a signal line and a picture element electrode, etc. Modifications can be made while the display device is assembled. First, light energy is irradiated onto the overlapping portion of the signal line and the conductive layer, thereby electrically connecting the signal line and the conductive layer. Next, the overlapping portion of the conductive layer and the conductive piece is irradiated with light energy, and the conductive layer and the conductive piece are electrically connected. Thereby, the signal line and the picture element electrode are directly electrically connected without using a switching element. Further, in a configuration in which the conductive layer is electrically connected to the scanning line or the additional capacitance electrode, the electrical connection between the conductive layer and the scanning line or the additional capacitance electrode is severed by irradiation with light energy.

The picture element electrode (
The voltage applied to the "corrected picture element electrode" will be explained below with reference to FIG. In FIG. 11, G represents the relationship between the signal voltage of the n-th scanning line (vertical axis) and time (horizontal axis), and S represents the relationship between the signal voltage of the m-th signal line (vertical axis) and Represents the relationship with time (horizontal axis). p
n represents a voltage applied to a normal picture element electrode connected to the nth scanning line and the mth signal line. P'n
c represents the voltage applied to the modified picture element electrode connected to the nth scanning line and the mth signal line.

G on the scan line. , G1+1, the signal (Vgh) that sequentially selects the switching elements has a selection time T. , will be output. Corresponding to the scanning line selection time T0°, a video signal voltage 8 is output to the signal line, and is P for a normal picture element electrode. As shown in , this signal voltage ■8 is the non-selection time T. It is held for tr. Then, the selection signal voltage ■
When gh is applied, a -va video signal is applied to the signal line.

On the other hand, the corrected picture element electrode has P'n. As shown in FIG. 2, since the video signal from the signal line is always applied, the modified picture element electrode cannot function normally. However, the picture element displayed by this modified picture element electrode performs a display corresponding to the effective value of the video signal applied to the signal line during one cycle when viewed over one cycle. Therefore, this picture element does not become a perfect bright spot or a black spot, but displays the average brightness of the picture elements arranged along the signal line. Therefore, this picture element becomes a picture element defect that is extremely difficult to identify.

It is necessary that the electrical resistance at the part connected by optical irradiation as described above is smaller than the resistance in the selected state of the switching element (hereinafter referred to as "on resistance"). . The reason is as follows.

The value of the on-resistance of the switching element is set so that a current sufficient to charge the picture element electrodes and electrodes flows within the time period during which the switching element is selected. Therefore,
If the resistance at the part where the above connection is made is greater than the on-resistance, the signal voltage that changes at each switching element selection time will not be reliably written to the modified picture element electrode, and the voltage applied to the modified picture element electrode will not be reliably written. The effective value becomes small. In such a state, the difference in brightness between the picture element displayed by the corrected picture element electrode and other normal picture elements becomes large,
This will be visually recognized as a pixel defect.

(Example) Examples of the present invention will be described below.

FIG. 1 shows a plan view of an active matrix substrate used in an embodiment of the display device of the present invention.

FIG. 2A shows an enlarged view of the vicinity of the conductive layer 34 in FIG. 1, and FIG.
The figure shows a sectional view taken along line nn in FIG. 1. ■-■ in FIG. 1 of a display device using the substrate of FIG. 1 in FIG.
A cross-sectional view along the line is shown. The active matrix display device of this example will be explained according to the manufacturing process. In this example, a transparent glass substrate was used as the insulating substrate. Gate bus wiring 2 functioning as a scanning line on the glass substrate l
1, a gate bus branch line 22 branching from the gate bus wiring 21, and a conductive layer 34 were formed. Gate bus wiring 2
1, and the gate bus branch line 22 are generally Ta, Ti, AI
, formed of a single layer of metal such as Cr or a multilayer metal of these,
In this example, Ta was used. The conductive layer 34 was also formed of the same metal as the gate bus wiring 21. The gate bus line 21, gate bus branch line 22, and conductive layer 34 are formed by patterning a Ta metal layer formed by sputtering. Before forming the gate bus wiring 21, the gate bus branch line 22, and the conductive layer 34, a base coat film made of Ta205 or the like may be formed on the glass substrate l.

Gate bus wiring 21, gate bus branch line 22 and conductive i layer 3
4, a base insulating film 11 made of SiNx was formed over the entire surface. The gate insulating film 11 is formed to a thickness of 3,000 wafers by plasma CVD.

Next, a TFT 31 functioning as a switching element was formed at the tip of the gate bus branch line 22.

A part of the gate bus branch line 22 is the gate electrode 2 of the TFT 31
Functions as 5. After forming the gate insulating film 11 as described above, an amorphous thin layer (a-3i) layer that will later become the channel layer 12 and an etching stopper layer 13 are formed.
A layer of SiN was deposited. The thickness of the a-3i layer is 300 layers, and the thickness of the SiN8 layer is 2000 layers. Next, the SiN layer is buttered and etched.
) I-bar layer 3 was formed. Furthermore, a contact layer 14 is later formed on the entire surface of the a-3i layer and the chingest rib layer 13.
．． An n''' type aSi layer doped with P (phosphorus), No. 14, was deposited to a thickness of 800 nm by plasma CVD.Next, the above a-3i layer and n'' type a-3i layer were Buttering was performed simultaneously to form the channel layer 12 and contact layers 14 and 14.

Next, a Ti metal layer which will later become the source electrode 32, the source bus wiring 23 functioning as a signal line, the drain electrode 33, and the conductive piece 35 was formed. The source bus wiring 23 and the like are generally formed of a single layer of metal such as T1, AI, Mo, Cr, or a multilayer metal thereof, but T1 was used in this embodiment. The T1 metal layer is formed by sputtering.

By patterning this Ti metal layer, a source electrode 32, a source bus wiring 23, a drain electrode 33, and a conductive piece 35 were formed. The source bus wiring 23 intersects with the gate bus wiring 21 with the aforementioned gate insulating film 11 in between. Further, as shown in FIG. 2B, the source bus wiring 23 is formed so as to overlap one end of the conductive layer 34 with the gate insulating film 11 in between. The conductive piece 35 is formed on the end of the conductive layer 34 that does not overlap with the source bus wiring 23, with the gate insulating film 11 interposed therebetween.

Next, as shown in FIG. 1, I To
A picture element electrode 41 made of (indium tin oxide) was formed. The picture element electrode 41 overlaps the end of the drain electrode 33 of the TFT 31 and is electrically connected to the drain electrode 33. Furthermore, as shown in FIG. 2B, the picture element electrode 41 is also formed to overlap the conductive piece 35.

Furthermore, SiN is applied to the entire surface of the substrate on which the picture element electrode 41 is formed.
A protective film 17 made of x was deposited. The protective film 17 may have a window-like shape that is removed above the center portion of the picture element electrode 41. An alignment film 19 was formed on the protective film 17. A counter electrode 3 and an alignment film 9 are formed on a glass substrate 2 facing the glass substrate l. A liquid crystal layer 18 is sandwiched between these substrates 1 and 2, and the active matrix display device of this embodiment is completed.

In the active matrix display device having the above configuration, if the TFT 31 becomes defective or a weak leakage current occurs between the source bus wiring 23 and the picture element electrode 41, a picture element defect occurs. In such a case, corrections are made as follows. First, an overlapping region 61 of the source bus wiring 23 and the conductive layer 34 shown by a broken line in FIG. 2A
(the part indicated by the arrow 65 in FIG. 2B), and the conductive layer 34
Light energy is irradiated onto the overlapping region 62 (the portion indicated by the arrow 64 in FIG. 2B) of the conductive piece 35 and the conductive piece 35. Thereby, the source bus wiring 23, the conductive layer 34, and the conductive piece 35 are electrically connected. Since the conductive piece 35 and the picture element electrode 41 are electrically connected, the picture element electrode 41 is connected to the source bus wiring 2.
It will be electrically connected to 3. In this example, YA, G laser light (wavelength: 1010 nm) is used as optical energy.
64n was used. The laser light may be irradiated from either of the substrates 1 and 2, but in many cases a light shielding film is formed on the substrate 2, and in that case, the laser light is irradiated from the substrate 1 side.

In this example as well, irradiation was performed from the substrate 1 side.

Since the signal from the source bus wiring 23 is always applied to the picture element electrode 41 (corrected picture element electrode) directly connected to the source bus wiring 23 as described above, the corrected picture element electrode functions normally. It is not possible.

However, since the picture element displayed by the modified picture element electrode performs a display corresponding to the effective value of the signal applied to the source bus wiring 23, this picture element does not become a complete bright spot or black spot. The average brightness of the picture elements arranged along the source bus wiring 23 is displayed. Therefore, this picture element becomes a picture element defect that is extremely difficult to identify.

Even when the laser beam is emitted as described above, the protective film 17 is still formed on the overlapping portion of the conductive layer 34 and the source bus wiring 23 and the overlapping portion of the conductive layer 34 and the conductive piece 35. Therefore, molten metal or the like does not mix into the liquid crystal layer 18, which is a display medium, and does not affect the display.

FIGS. 4A to 4C show other embodiments of the active matrix substrate used in the display device of the present invention. In the substrate of FIG. 4A, the source bus wiring 23 is provided with a protrusion 23a, and the conductive layer 34 is superimposed on the protrusion 23a. The configurations of the other conductive pieces 35 and the like are similar to those shown in FIG.

In the embodiment of FIG. 1, the conductive layer 34 and the conductive piece 35 are TFTs.
31, but it may be provided at any position as long as it is close to the source bus wiring 23. FIG. 4B shows an example in which a conductive layer 34 is formed near the TFT 31.

In the embodiment shown in FIG. iA C, a source bus branch line 23b is formed that branches off from the source bus arrangement %23. The conductive layer 34 is formed in parallel to the source bus wiring 23 and overlaps the source bus branch line 23b.

In a display device using any of the substrates shown in FIGS. 4A to 4C, pixel defects are corrected in the same manner as in the embodiment shown in FIG. Although not shown, the conductive layer 34, the conductive piece 35, etc. are connected to the source bus wiring 2 shown in FIGS. 4A to 4C.
3 is the source bus wiring 2 on the opposite side of the pixel electrode 41.
It is also possible to adopt a configuration provided in 3.

FIGS. 5A and 5B show other embodiments of the active matrix substrate used in the display device of the present invention. In the active matrix substrate of FIG. 1 and FIGS. 4A to 4C described above, only the gate insulating film 11 exists between the conductive layer 34 and the source bus wiring 11I23, so that the source bus wiring 23 and the conductive layer 34 and between the conductive layer 34 and the conductive piece 35 may spontaneously short-circuit.

The active matrix substrate shown in FIGS. 5A and 5B solves this problem. The conductive layer 34 of the substrate shown in FIG. 5A has a pixel electrode 4 superimposed on the conductive layer 34.
The gate bus wiring 21 is connected to the gate bus wiring 21 adjacent to the gate bus wiring 21 connected to the gate bus wiring 1. Gate bus wiring 2
1, an anodic oxide film is often formed on it to ensure insulation of the cathode wiring 21. By forming the conductive layer 34 connected to the gate bus wiring 21 as in this embodiment, it is possible to form an anodic oxide film also on the conductive layer 34. When the anodic oxide film is formed on the conductive layer 34, short circuits between the source bus wiring 23 and the conductive layer 34 and between the conductive layer 34 and the conductive piece 35 are prevented.

In the substrate of FIG. 5B, the conductive layer 34 and the conductive piece 35 are T
It is provided at the corner opposite to FT31. Therefore, in this embodiment, the conductive layer 34 overlaps the source bus wiring 23 adjacent to the source bus wiring connected to the picture element electrode overlaid on the conductive layer 34.

If a pixel defect occurs in a display device using the substrates shown in FIGS. 5A and 5B, the connection between the conductive layer 34 and the source bus wiring 23 is similar to the embodiment shown in FIG. and between the conductive layer 34 and the conductive piece 35. Furthermore, in these substrates, light energy is irradiated to a region 63 indicated by a broken line in FIGS. 5A and 5B, and the conductive layer 34 and the gate bus wiring 21 are disconnected. By performing the connection and disconnection by light energy irradiation as described above, the picture element electrode 41 is directly connected to the source bus wiring 23. Note that if such correction is made, the first board in FIG. 5A will be
Similar to the substrate shown in the figure, the picture element electrode 41 is directly connected to the source bus wiring 23 which was connected through the TFT 31, but in the board shown in FIG. 5B, the picture element electrode 41 was connected through the TFT 31. It is connected to the source bus wiring 23 which is adjacent to the source bus wiring 23.

FIG. 6 shows another embodiment of the active matrix substrate used in the display device of the present invention. In this embodiment, the conductive layer 34 is formed below the mutually adjacent picture element electrodes 41a and 41b and the source bus wiring 23. In this embodiment, one conductive layer 34 is provided for every two picture element electrodes. Conductive pieces 35a and 35b are formed on both ends of the conductor 1134 with the gate insulating film 11 in between. The picture element electrodes 41a and 411) are directly superimposed on the conductive pieces 35a and 35t), respectively.

Further, the conductive layer 34 is formed to be electrically connected to the gate bus wiring 21 adjacent to the gate bus wiring connected to the picture element electrodes 41a and 41b superimposed above the conductive layer 34. By forming the conductive layer 34 connected to the gate bus wiring 21, an anodic oxide film can be formed on the conductive layer 34.

In the display device using the substrate of this embodiment, the picture element electrode 41
When a pixel defect occurs in the source bus wiring 23.a or 1b, the source bus wiring 23. A laser beam is irradiated onto the overlapping portion of the conductive layer 34 and the conductive layer 34 . Next, if a pixel defect has occurred in the pixel electrode 41a, a portion where the conductive layer 34 and the conductive piece 35a overlap,
If a pixel defect occurs in the pixel electrode 41b, a laser beam is irradiated onto the overlapping portion of the conductive layer 34 and the conductive piece 351).

Further, a region 63 indicated by a broken line in FIG. 6 is irradiated with laser light, and the electrical connection between the conductive layer 34 and the gate bus wiring 21 is severed. With the above modification, the picture element electrode 41a or 41b that is causing the picture element defect is directly connected to the source bus wiring 23.

In the above case, if a pixel defect occurs in both the pixel electrodes 41a and 41b, by directly connecting both the pixel electrodes 41a and 41b to the source bus wiring 23, any pixel defect can be removed. will also be corrected.

Further, although the present embodiment shows a configuration in which the conductive layer 34 is connected to the gate bus wiring 21, a configuration in which the conductive layer 34 is not connected to the gate bus wiring 21 may be adopted.

The configuration of FIG. 1 can also be applied to an active matrix display device having an additional capacitance 42, as shown in FIG. The display device shown in FIG. 7 is obtained by adding an additional volume fi42 to the embodiment shown in FIG. 4B described above. The additional capacity 142 is
Overlapping portion (shaded portion) of the additional capacitance electrode 24 provided on the substrate l in parallel with the gate bus wiring 21 and the pixel electrode 41
is formed. In the display device shown in FIG. 7 as well, pixel defects can be corrected in the same way as in the embodiment shown in FIG. 1 described above. Conductive layer 34, conductive piece 35, and source bus wiring 2
The configuration of No. 3 may also be as shown in FIG. 1, FIG. 4A, and FIG. 4C described above. Furthermore, in FIG. 7, the conductive layer 34 and the conductive piece 35 may have the configurations shown in FIGS. 5A, 5B, and 6. When the conductive layer 34 and the conductive piece 35 are configured as shown in these figures, the conductive layer 34 is electrically connected not to the gate bus wiring 21 but to the additional capacitance electrode 24. - As an example, FIG. 9 shows a case where the conductive layer 34 and the conductive piece 35 are configured as shown in FIG. 6. In the active matrix substrate shown in FIG. 9, the conductive layer 34 is connected to the additional capacitance electrode 24. An anodic oxide film is often formed on the additional capacitance electrode 24 as well. Therefore, the conductive layer 34 is connected to the additional capacitance electrode 24.
By connecting to the conductive layer 34, an anodic oxide film can also be formed on the conductive layer 34.

Furthermore, the present invention can also be applied to an active matrix display device having the configuration shown in FIG. This display device is similar to the display device shown in FIG. 7, but the reduction in the area of the opening due to the portion occupied by the additional volume j142 is suppressed. That is, in this display device, the width of the gate bus wiring 21 is increased so that it overlaps with a part of the picture element electrode 41. In this configuration, the adjacent non-selected gate bus wiring 21 can be used as an electrode for additional capacitance. Moreover, since there is no gap between the gate bus wiring 21 and the additional capacitance electrode 24 as shown in FIG. 7, it is possible to suppress a reduction in the area of the opening. In this display device as well, pixel defects are corrected in the same manner as in the embodiment shown in FIG. Also in this embodiment, the conductive layer 34, the conductive piece 35, and the source bus wiring 2
The configuration of No. 3 may also be as shown in FIGS. 1, 4A, and 4C described above. Furthermore, in FIG. 8, the conductive layer 34 and the conductive piece 35 may have the configurations shown in FIGS. 5A, 5B, and 6. - As an example, FIG. 10 shows a substrate in which the conductive layer 34 and conductive piece 35 of FIG. 8 are configured as shown in FIG. 6.

In the above embodiment, an example was shown in which the gate electrode of the TFT 31 was formed on the bottom and the source and drain electrodes were formed on the top. It is also possible to use a TPT of Further, although the TFT 31 is formed on the gate bus branch line 22, it may be formed on the gate bus line 21 and the branch line from the source bus line 23 is connected to the source electrode.

Further, in the above embodiments, a TPT is used as a switching element, but other than TPT, for example, an MIM element, a MOS (MOS) transistor element, a diode, a varistor, etc. may be used.

(Effects of the Invention) In the active matrix display device of the present invention, pixel defects can be corrected in a way that makes them inconspicuous while the display device is in a state where pixel defects can be easily detected. Therefore, according to the present invention, it is possible to produce display devices with high yield, and it is possible to contribute to reducing the cost of display devices.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an active matrix substrate used in an active matrix display device according to an embodiment of the present invention, FIG. 2A is an enlarged plan view of the vicinity of the conductive layer in FIG. 1, and FIG.
The figure is a cross-sectional view taken along the line ■-■ in FIG. 1, FIG. 3 is a cross-sectional view taken along the line ■-m in FIG. 1 of a display device using the substrate in FIG. 1, and FIG. 4A. ~ Figures 4C, 5A ~ 5B, and 6 are plan views of other embodiments of the substrate used in the display device of the present invention, and Figures 7 and 8 are plan views of the display device of the present invention, respectively. FIGS. 9 and 10 are plan views of other embodiments of the substrate having additional capacitance electrodes constituting the display device of the present invention, respectively. A plan view, FIG. 11 is a diagram showing the relationship between the signals applied to the scanning line and the signal line and the voltage of the picture element electrode,
FIG. 12 is a plan view of an active matrix substrate used in a conventional active matrix display device. 1, 2...Glass substrate, 3...Counter electrode, 9,1
9... Orientation film, 11... Gate insulating film, 12...
Channel fi, 13... Etching stopper [, 14
... Contact layer, 18... Liquid crystal layer, 21... Gate bus wiring, 22... Gate bus branch line, 23...
Source bus wiring, 24... electrode for additional capacitance, 25...
- Gate electrode, 31... TFT, 32... Source electrode, 33... Drain electrode, 34-... Conductive layer, 35
, 35a, 35b・-conductive piece, 41.41a, 41b・
-Picture element electrode, 42-...additional capacitance. Above 2A 2B Figure 1 3 Figure 5A Figure 5B Kasumi 6 En 9 Circle Figure 7 8 Figure 11

Claims (1)

[Claims] 1. A pair of insulating substrates, at least one of which is translucent, scanning lines and signal lines wired vertically and horizontally on one of the pair of substrates, and the scanning lines and a pixel electrode connected to the signal line via a switching element, the active matrix display device comprising: a pixel electrode connected to the signal line via a switching element, the signal line and the pixel electrode being superimposed below the signal line and the pixel electrode with an insulating film interposed therebetween. An active matrix display device comprising a conductive layer and a conductive piece formed between the picture element electrode and the insulating film. 2. A pair of insulating substrates, at least one of which is translucent, scanning lines and signal lines wired vertically and horizontally on one of the pair of substrates, and the scanning lines and the signal lines. An active matrix display device comprising: picture element electrodes connected via a switching element, wherein conductive conductors are superposed below the signal line and the pair of adjacent picture element electrodes with an insulating film interposed therebetween. An active matrix display device comprising: a layer; and conductive pieces formed between the pair of picture element electrodes and the insulating film. 3. Claim 1 or 2, wherein the conductive layer is electrically connected to a scanning line adjacent to the scanning line connected to the picture element electrode, and an anodic oxide film is formed on the conductive layer. The active matrix display device described in . 4. Further comprising an additional capacitor electrode facing the picture element electrode with the insulating film in between, the conductive layer being electrically connected to the additional capacitor electrode, and an anodic oxide film on the conductive layer. The active matrix type display device according to claim 1 or 2, wherein the active matrix display device is formed.