JPH04291321A - Active matrix liquid crystal device - Google Patents

Abstract

PURPOSE:To provide the active matrix liquid crystal display device which allows the detection and correction of the shorting defect of a thin-film transistor (TFT) relating to the active matrix liquid crystal display device constituted to obtain a display device free from display defects. CONSTITUTION:This active matrix liquid crystal display device consisting of the TFT is provided with the plural thin film TFTs for driving picture elements at each one picture element and consists of the constitution provided with a 1st electrode which connects any one electrode among a gate bus line electrode, drain bus line electrode and picture element electrode and any one electrode among the gate electrode G, drain electrode D and source electrode S of the TFT and is opened by irradiation with laser and a 2nd electrode which connects the 1st electrode by irradiation with a laser and an electrode which is disposed in electrical parallel with the 1st electrode and is connected by the 1st electrode before cutting by irradiation with the laser.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active matrix liquid crystal display device, and more particularly to an active matrix liquid crystal display device having a structure that allows a display device with fewer display defects to be obtained.

[0002] In recent years, liquid crystal display devices have been widely adopted as display devices for small information processing devices such as word processors and laptop computers, terminal devices, and video devices because of their features such as thinness, weight, and low power consumption. There is. Since these display panels display fine characters and numbers, a defect-free display screen is required. In particular, there is a strong demand for defect-free panels for displays of information processing devices.

The panel of an active matrix liquid crystal display device is for color display and has, for example, 640 horizontal dots (×
3 colors) x 480 vertical dots with a total of 100,000 pixels are manufactured. When forming such a large number of pixels, it is technically difficult to manufacture them without defects.

0004

2. Description of the Related Art FIG. 19 shows a plan view of one pixel of a defect-free display panel of a liquid crystal display device according to the prior art. The display panel is composed of an active matrix of thin film transistors. In the figure, 10 and 11 are gate bus lines constituting an active matrix, 20 is a drain bus line, and 30 is a pixel electrode that applies voltage to a liquid crystal (not shown). 40 and 41 are thin film transistors, and G, D, and S represent the gate electrode, drain electrode, and source electrode of the thin film transistors, respectively. The two gate electrodes G are connected to the gate bus lines 10 and 11, respectively, and the drain electrode D is connected to the drain bus line 20.
The source electrode S is connected to the pixel electrode 30. As shown in the figure, two thin film transistors 40 and 41 are connected to the pixel electrode in a redundant configuration.

With this redundant configuration, if one of the two thin film transistors 40 and 41 becomes open (open) during the manufacturing process, the pixel electrode 30 is driven by the other thin film transistor. This allows writing to be performed automatically, and defects are automatically prevented without any special defect correction. It is considered that the probability that the two thin film transistors 40 and 41 become open failures at the same time is so small that it can be virtually ignored.

[0006]

[Problem to be Solved by the Invention] This redundant configuration in which two thin film transistors are provided in one pixel is effective against open defects as described above, but in the case of short circuit defects due to short circuits of thin film transistors, Even if one thin film transistor is normal, the pixel potential will always be the gate potential or drain potential, causing point defects and gate bus
The drain bus causes an intervening line defect through the shorted thin film transistor. For this reason, it is essential to identify a defective transistor and repair the transistor using a laser or the like.

[0007] To completely detect defective transistors, the gates and drains of multiple thin film transistors must be connected to separate bus line electrodes, but this requires an area for wiring the electrodes and an opening. disadvantageous in terms of rate. Currently, a plurality of thin film transistors are connected to the same gate bus line and drain bus line, and it is impossible to completely detect a short-circuited transistor, and therefore it is impossible to correct the defect using a laser.

An object of the present invention is to provide a defect-free panel structure in which a short-circuit defect in one transistor can be detected and corrected in an active matrix display device in which one pixel is driven by a plurality of transistors. An object of the present invention is to provide an active matrix liquid crystal display device.

[0009]

[Means for Solving the Problems] An active matrix liquid crystal display device using thin film transistors of the present invention includes a plurality of pixel driving thin film transistors (42
, 43) and gate bus line electrodes (12, 13).
and drain bus line electrode (21) and pixel electrode (31)
and one of the gate electrode (G), drain electrode (D), and source electrode (S) of the thin film transistor, and is opened by laser irradiation. A first electrode (60, 61) and a second electrode (60, 61) that is electrically arranged in parallel with the first electrode and that is connected by laser irradiation between the electrodes that were connected by the first electrode before cutting. 50, 51).

Furthermore, in an active matrix display device using thin film transistors according to another aspect of the present invention, one pixel is formed of two divided regions (32, 33), and each pixel region is provided with one pixel. thin film transistors (44, 45) that drive the divided pixels; a first electrode (66) that connects the divided regions and can be disconnected by receiving laser irradiation; and a first electrode (66) that can connect the divided pixels by receiving laser irradiation. and a second electrode (56).

[0011]

[Operation] Fig. 1 shows a basic conceptual diagram of the invention. A and B are thin film transistors provided in one pixel, and C is a pixel electrode, a gate bus line electrode, or a drain bus line electrode to be connected to the thin film transistors A and B. Between the thin film transistors A and B and the electrode C, there is a first electrode P indicated by a solid line, and a second electrode indicated by a broken line.
An electrode R is arranged. Although the first electrode P is manufactured in a connected state, it can be fused and cut by laser irradiation. Although the second electrode R is electrically in parallel with the first electrode P, it is in an open state during manufacturing and can be connected by laser irradiation.

Here, if one of the two thin film transistors A and B is defective due to a short circuit, the method for detecting which thin film transistor is defective is as follows. (1) First, the first electrode P of any one thin film transistor, for example A, is cut off using a laser. If the display defect is repaired by disconnecting, the disconnected thin film transistor A has a short-circuit defect, so the repair is completed without performing any operation on the thin film transistor B. (2) On the other hand, if the defect is not repaired even if the first electrode P of the thin film transistor A is separated, the other thin film transistor B is defective, so Connect the arranged second electrode R by laser irradiation to restore the function,
Furthermore, the first electrode P of the short-circuit defective thin film transistor B
Separate by laser irradiation.

According to another active matrix liquid crystal display device having the structure of the present invention, the electrode C is a pixel electrode, and the pixel electrode C is divided into two, and the first electrode P and the first electrode are arranged between the divided regions. Two electrodes R are arranged. When a defect occurs, the first electrode between the divided regions is cut. Then, since there are two sets (transistor+pixel), the defective transistor can be identified. The defect can be corrected by separating the defective transistor and connecting the divided regions using a second electrode. In this way, effects similar to those described above can be obtained.

[0014]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a plan view showing the electrode structure of one pixel of the first embodiment of the active matrix liquid crystal display device according to the present invention. FIG. 3 is a cross-sectional view taken along line II in FIG. 2, and is a cross-sectional view of an active matrix thin film transistor. FIG. 4 is an equivalent circuit diagram of the configuration of FIG. 2. Like reference numbers or symbols in the figures indicate the same thing. 12 and 13 are gate bus lines forming an active matrix, 21 is a drain bus line, and 31 is a pixel electrode that applies a voltage to a liquid crystal (not shown). 42 and 43 are thin film transistors, G1 and G2
, D, and S represent the gate electrode, drain electrode, and source electrode of the thin film transistor, respectively. Gate electrode G1,G
2 are connected to the gate bus lines 12 and 13, respectively, the drain electrode D is connected to the drain bus line 21, and the source electrode S is connected to the pixel electrode 31. 50
, 51 are auxiliary electrodes for correction. Auxiliary electrodes 50, 51
is the connection portion 60, 6 between the source electrode S and the pixel electrode 31.
It is arranged in a structure that bypasses 1.

Next, referring to FIGS. 2 and 3, the auxiliary electrode 5
The structure of Nos. 0 and 51 will be explained in more detail in relation to the method of manufacturing a thin film transistor.

The thin film transistor 42 (same as 43) is formed as follows. T on the transparent glass substrate 70
An i (titanium) or Cr (chromium) material is deposited over the entire surface by sputtering and patterned to form gate bus lines 12, 13, gate electrodes G1, G2, and auxiliary electrodes 50, 51. Next, a gate insulating film 71 and a semiconductor layer 72 made of an a-Si (amorphous silicon) material are successively deposited thereon by plasma CVD (PCVD) and patterned in a transistor pattern. Furthermore, an n+ type a-Si layer 73 and a source electrode S (connected to the electrodes 60 and 61) and a drain electrode D (connected to the drain bus line 21) made of Al material are deposited by PCVD and sputtering to form a common electrode pattern. pattern. Finally, ITO (indium tin oxide) material is deposited by sputtering and patterned in the pattern of the pixel electrode 31. In the plan view of FIG.
1 is bypassed in an L-shape, and during manufacturing, as shown in FIG.
are insulated from each other.

The equivalent circuit diagram in FIG. 4 is a simplified circuit diagram of the structure of the first embodiment described above. Figure 4
The source electrode S and the pixel electrode 31 are connected by two lines, a solid line and a dotted line. The solid line corresponds to the electrode connection parts 60, 61, and the dotted line corresponds to the auxiliary electrodes 50, 51.
corresponds to That is, by cutting the connecting portions 60 and 61, the thin film transistor can be separated from the pixel electrode, and it is possible to detect the presence or absence of a short-circuit defect in the transistor. Furthermore, by connecting the auxiliary electrodes 50 and 51, it is possible to restore the connection of a normal transistor that has been disconnected upon detection of a defect.

Next, referring to FIGS. 5 and 6, the connecting portion 60
, 61 and how to connect the auxiliary electrode will be explained.

FIG. 5 is a sectional view taken along the line II--II in FIG. 2. The left side of FIG. 5 shows the state before laser irradiation. The right side of FIG. 5 shows the state after the II-II portion is irradiated with the laser. The source electrode material (same as the drain electrode material) that has been irradiated with the laser is scattered by the laser irradiation, and the connection portion 60 is in an open state.

FIG. 6 is a sectional view taken along line III--III in FIG. 2. The left side of FIG. 6 shows the state before laser irradiation. The right side of FIG. 6 shows the state after the III-III portion is irradiated with the laser. A hole is formed in the center of the electrode material irradiated with the laser, but the source electrode material dissolved in liquid flows on the wall surface surrounding the hole and comes into contact with the auxiliary electrode 50 to establish an electrical connection. That is, the source electrode S and both ends of the auxiliary electrode 50 are connected. Note that the portions of the opposite ends of the auxiliary electrodes 50 and 51 that overlap with the source electrode S also have the same cross-sectional structure as III-III, and are connected by laser in the same manner. Either one may be connected from the beginning.

The above can be summarized as follows. If one of the two thin film transistors 42 and 43 is defective due to a short circuit, the following procedure is used to detect which thin film transistor is defective. (1) First, the connection portion 60 of any one thin film transistor, for example 42, is cut off using a laser. If the display defect is repaired by disconnecting, the disconnected thin film transistor 42 is defective due to a short circuit, so the repair is completed without performing any operation on the thin film transistor 43. (2) On the other hand, if the defect is not repaired even if the connecting portion 60 of the thin film transistor 42 is disconnected, the other thin film transistor 43 is defective and is placed in parallel with the disconnected connecting portion 60 of the normal thin film transistor 42. Both ends of the auxiliary electrode 50 are connected to the source electrode by laser irradiation to restore the function, and further, the connection portion 61 of the short-circuited thin film transistor 43 is separated by laser irradiation. The configuration of the first embodiment is effective in the case of a short-circuit failure between the gate and source or between the drain and source of a thin film transistor.

Note that a YAG laser can be used as the laser for irradiation. Since the required laser intensity may be different for cutting and connecting, it is preferable to set appropriate values for each in advance.

Next, a second embodiment of the present invention will be described with reference to FIGS.
0. In this embodiment, electrode connection parts 62 and 63 that can be cut by a laser are provided between the drain bus line 21 and the drain electrode D, and auxiliary electrodes 52 and 53 that can be connected by a laser are provided in parallel with the electrode connection parts 62 and 63. Established. Note that the cross-sectional structure of this second embodiment along the line II is substantially the same as that of FIG. 3 described in the first embodiment. The auxiliary electrodes 52 and 53 are formed of the same material on the glass substrate 70 at the same time as the gate bus lines 12 and 13 and the gate electrode G, as in the first embodiment.

The equivalent circuit diagram in FIG. 8 is a simplified representation of the structure of the second embodiment described above. In FIG. 8, the drain electrode D and the drain bus line 21 are connected by two lines, a solid line and a dotted line. The solid line corresponds to the electrode connection parts 62 and 63, and the dotted line corresponds to the auxiliary electrode 52.
, 53. That is, by cutting the connecting portions 62 and 63, the drain electrode D is connected to the drain bus line 2.
1, and it is possible to detect whether or not there is a short-circuit defect in the transistor. Furthermore, by connecting the auxiliary electrodes 52 and 53, it is possible to restore the connection of a normal transistor whose drain has been disconnected upon detection of a defect.

[0026] Also, the cutting method in II-II, and the cutting method in II-II.
The connection method in I-III is also basically the same as that shown in FIGS. 5 and 6 described in the first embodiment, but cross-sectional views thereof are shown in FIGS. 9 and 10. The procedure for disconnecting and connecting is as follows. (1) First, the connecting portion 62 of any one arbitrary thin film transistor, for example 42, is cut off using a laser as shown in FIG. If the display defect is repaired by disconnecting, the disconnected thin film transistor 42 is defective due to a short circuit, so the repair is completed without performing any operation on the thin film transistor 43. (2) On the other hand, if the defect is not repaired even if the connecting portion 62 of the thin film transistor 42 is disconnected, the other thin film transistor 43 is defective, so it is not placed in parallel with the disconnected connecting portion 62 of the normal thin film transistor 42. Both ends of the auxiliary electrode 52 are connected to the drain electrode by laser irradiation as shown in FIG. 10 to restore the function.
Furthermore, the connecting portion 6 of the short-circuit defective thin film transistor 43
3 is separated by laser irradiation as shown in FIG. The configuration of this second embodiment is effective in the case of a short circuit between the gate and drain or between the drain and source of a thin film transistor.

Next, a third embodiment of the present invention is shown in FIGS. 11 to 14. In this embodiment, electrode connection parts 64 and 65 that can be cut by a laser are provided between the gate bus lines 12 and 13 and the gate electrodes G1 and G2, and auxiliary electrodes that can be connected by a laser are provided in parallel thereto. 54,
55 was established. Note that the cross-sectional structure of the third embodiment along line II is substantially the same as that of FIG. 3 described in the first embodiment. FIG. 12 shows a simplified circuit diagram of the structure of the third embodiment. In FIG. 10, the gate electrodes G1, G2 and the gate bus lines 12, 13 are connected by two lines, a solid line and a dotted line. The solid lines correspond to the electrode connection parts 64 and 65, and the dotted lines correspond to the auxiliary electrodes 54 and 55. That is, the connection part 6
By cutting 4 and 65, the gate electrode can be separated from the gate bus line, and the presence or absence of a short-circuit failure in the transistor can be detected. Furthermore, by connecting the auxiliary electrodes 54 and 55, it is possible to restore the connection of a normal transistor whose gate was cut off for defect detection.

However, the difference between the first and second embodiments is as follows.
In the first and second embodiments, the auxiliary electrode connectable by laser is formed on the glass substrate using a gate electrode material at the same time as the gate line, whereas in the third embodiment, the auxiliary electrode 5
4 and 55 are the drain bus line 21 and the drain electrode D
, a gate insulating film 71 made of the same material as the source electrode S.
formed on top of. However, the fact that the auxiliary electrodes 54, 55 and the gate electrode are melted by laser irradiation and connected as shown in FIG. 6 is substantially the same as in the first and second embodiments.

The cutting method on the II-II line in FIG. 11 and the connecting method on the III-III line in FIG. 11 are also substantially the same as those in FIGS. 5 and 6 explained in the first embodiment, but The cross-sectional structure is shown in FIGS. 13 and 14. The procedure for laser cutting and connection is as follows. (1) First, the connecting portion 64 of any one arbitrary thin film transistor, for example 42, is cut off using a laser as shown in FIG. If the display defect is repaired by disconnecting, the disconnected thin film transistor 42 is defective due to a short circuit, so the repair is completed without performing any operation on the thin film transistor 43. (2) On the other hand, if the defect is not repaired even if the connecting portion 64 of the thin film transistor 42 is disconnected, the other thin film transistor 43 is defective and is placed in parallel with the disconnected connecting portion 64 of the normal thin film transistor 42. Both ends of the auxiliary electrode 54 are connected to the drain electrode by laser irradiation as shown in FIG. 14 to restore the function.
Furthermore, the connecting portion 6 of the short-circuit defective thin film transistor 43
5 is separated by laser irradiation as shown in FIG. The configuration of this third embodiment is effective in the case of a short-circuit failure between the gate and source or between the gate and drain of a thin film transistor.

Next, a fourth embodiment of the present invention will be described with reference to FIGS. 15 to 18. In this embodiment, the pixel electrode of one pixel is divided into two as shown in FIG.
4 and 45 are connected to each other. Divided pixel electrode 32
, 33 can be cut with a laser. Further, an auxiliary electrode 56 is formed below the pixel electrode with a gate insulating layer interposed therebetween, so as to be in parallel with the connection portion 66 and spanning the divided pixel electrodes 32 and 33. Similar to the first and second embodiments, this auxiliary electrode 56 is made of gate electrode material and is used for the gate bus lines 12, 13 and the gate electrodes G1, G2.
At the same time, it is formed on the glass substrate 70.

The cross-sectional structure of this third embodiment along line II is substantially the same as that shown in FIG. 3 described in connection with the first embodiment.

FIG. 16 shows a simplified circuit diagram of the structure of the fourth embodiment described above. In FIG. 16, the divided pixel electrodes 32 and 33 are connected by two lines, a solid line and a dotted line. The solid line corresponds to the electrode connection portion 66, and the dotted line corresponds to the auxiliary electrode 56. That is,
By cutting the connecting portion 66, the pixel can be separated into two divided pixel electrodes, and it can be determined which transistor is defective in short circuit. Furthermore, by connecting the auxiliary electrode 56, the separated divided pixel electrodes 32 and 33 can be electrically connected again.

Line II-II and III-II in FIG.
The cross-sectional structure taken along line I is shown in FIGS. 17 and 18, respectively. Also, the method of cutting along the II-II line, and the method of cutting along the II-II line.
The connection method for the I line is also the same as that shown in FIGS. 5 and 6 described in the first embodiment, but the procedure is slightly different as follows. (1) First, as shown in FIG. 17, the connection portion 66 of the pixel electrode is separated by a laser so that the divided pixels 32 and 33 are driven independently by separate thin film transistors 44 and 45, respectively. Among the upper and lower divided pixels, the transistor connected to the divided pixel with the display defect has a short-circuit defect, so that transistor is separated from the pixel electrode. (2) Furthermore, both ends of the auxiliary electrodes 56 of the divided pixel electrodes 32 and 33 are connected and recombined using a laser as shown in FIG.

The configuration of the fourth embodiment is particularly effective in the case of a short-circuit failure between the gate and source or between the source and drain of a thin film transistor.

In the above four embodiments, both ends of the auxiliary electrode were initially insulated from the pixel electrode or bus line above by the gate insulating film, but only one end of the auxiliary electrode was insulated. If the other end is connected from the beginning, the connection process by laser irradiation can be performed at only one place, thereby shortening the process time.

Two or more of the above embodiments may be combined. By appropriate combinations, it is possible to detect and correct short-circuit defects between any of the gate, drain, and source electrodes of a thin film transistor. Needless to say, open defects can be automatically corrected because one pixel electrode is driven by two thin film transistors, as in the conventional case.

[0037]

Effects of the Invention According to the configuration of the present invention described above, a connection electrode that can be fused with a laser and an auxiliary electrode that can be connected with a laser are connected in parallel between the electrode of a thin film transistor and the bus line or pixel electrode of a matrix. Alternatively, one pixel can be divided into two divided regions, and a connection electrode that connects the divided regions and can be disconnected by laser irradiation, and a connection electrode that can be connected between the divided pixels by laser irradiation. By arranging possible auxiliary electrodes in parallel, it is possible to identify short-circuited transistors and correct their display defects, creating a defect-free active matrix liquid crystal that can handle both short-circuit and open defects. A display device can be provided.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram for explaining the principle of the present invention.

FIG. 2 is a plan view of one pixel of a first embodiment of an active matrix display device according to the present invention.

FIG. 3 is a cross-sectional view of the embodiment of FIG. 2;

FIG. 4 is an equivalent circuit diagram of the embodiment of FIG. 2;

FIG. 5 is a sectional view illustrating electrode cutting in the embodiment of FIG. 2;

FIG. 6 is a cross-sectional view illustrating electrode connections in the embodiment of FIG. 2;

FIG. 7 is a plan view of one pixel of a second embodiment of an active matrix display device according to the present invention.

FIG. 8 is an equivalent circuit diagram of the embodiment of FIG. 7;

9 is a diagram illustrating electrode cutting in the embodiment of FIG. 7; FIG.

FIG. 10 is a diagram illustrating electrode connections in the embodiment of FIG. 7;

FIG. 11 is a plan view of one pixel of a third embodiment of an active matrix display device according to the present invention.

FIG. 12 is a conceptual diagram for explaining the principle of the embodiment of FIG. 11;

FIG. 13 is a diagram illustrating electrode cutting in the embodiment of FIG. 11;

14 is a diagram illustrating electrode connections in the embodiment of FIG. 11. FIG.

FIG. 15 is a plan view of one pixel of a fourth embodiment of an active matrix display device according to the present invention.

16 is a conceptual diagram for explaining the principle of the embodiment of FIG. 15. FIG.

17 is a diagram illustrating electrode cutting in the embodiment of FIG. 15. FIG.

18 is a diagram illustrating the electrode connection of FIG. 15. FIG.

FIG. 19 is a plan view showing an electrode connection configuration in one pixel of an active matrix liquid crystal display device according to the prior art.

[Explanation of symbols]

10, 11, 12, 13...gate bus line 20
, 21...Drain bus line 30, 31, 32
, 33...pixel electrodes 40, 41, 42, 43, 44
, 45... Thin film transistors 50, 51, 52, 53, 54, 55, 56... Auxiliary electrodes 60, 61, 62, 63, 64, 65, 66... Electrode connection portion 70... Transparent substrate 71...Gate insulating film 72...A-Si semiconductor layer 73...N+ type a-Si layer

Claims (4)

[Claims] Claim 1: In an active matrix liquid crystal display device in which a plurality of pixel driving thin film transistors (42, 43) are provided for one pixel, gate bus line electrodes (12, 13), drain bus line electrodes (21), and pixel electrodes are provided. (31) and the gate electrode (G1, G2) of the thin film transistor and the drain electrode (
D) and either one of the source electrodes (S) are connected to each other, and the connection can be cut by laser irradiation: a first electrode (60, 61); and second electrodes (50, 51) that are electrically arranged in parallel with the first electrode and that are connectable by laser irradiation. [Claim 2] One pixel is divided into two divided regions (
32, 33), and thin film transistors (32, 33) provided in each region of the pixel and driving the pixels.
44, 45), a first electrode (66) that connects the regions and is capable of cutting the connection upon laser irradiation, and a first electrode (66) that connects the divided regions upon laser irradiation. an active matrix liquid crystal display device comprising: two electrodes (56); 3. A transparent substrate (70), a gate electrode (G1, G2) formed on the transparent substrate, a gate insulating layer (71) covering the gate electrode, and a layer laminated on the gate insulating layer. A plurality of thin film transistors (42, 43) including a semiconductor layer (72, 73), source/drain electrodes (S, D) formed on the semiconductor layer, and a drain connected to the drain electrode and the gate electrode, respectively. Bus line electrode (21) and gate bus line electrode (12,1
3) and a pixel electrode (31) formed on the gate insulating layer and driven by the thin film transistor, further comprising two thin film transistors (31) for one pixel electrode.
42, 43) are provided, and one of the gate bus line electrode, the drain bus line electrode, and the pixel electrode, and one of the gate electrode, drain electrode, and source electrode of the thin film transistor. preliminary electrodes (50, 51) that straddle the gate insulating layer between the electrodes;
An active matrix liquid crystal display device comprising: formed on the transparent substrate. 4. A transparent substrate (70), a gate electrode (G1, G2) formed on the transparent substrate, a gate insulating layer (71) covering the gate electrode, and a layer laminated on the gate insulating layer. A plurality of thin film transistors including semiconductor layers (72, 73), source/drain electrodes (S, D) formed on the semiconductor layer, and a pixel formed on the gate insulating layer and driven by the thin film transistor. In the active matrix liquid crystal display device having electrodes, one pixel further has two pixel electrodes (32, 33) connected at a portion (66), and the two divided pixel electrodes are each separated from each other. The thin film transistor (4
4, 45), and a preliminary electrode (56) is formed on the transparent substrate to straddle the divided pixel electrodes via the gate insulating layer.