JPH103092A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a liquid crystal display device whose manufacturing yeild is satisfactory, in which an after-image is little, and which has a wide visual field angle and a high display quality, in the active matrix type liquid crystal display device of a traverse electric field system. SOLUTION: This device is constituted of scanning signal lines 1, video signal wirings 2. pixel electrodes, pixel electrodes, common electrodes 3 and active elements formed on a glass substrate 10 and is made to be a traverse electric field driving system performing a picture display by driving liquid crystal moleculars by the electric field of a direction roughly parallel with the surface of the glass substrate 10. The scanning signal lines 1, video signal wirings 2, the pixel electrodes and the common electrodes 3 are respectively separated by insulating films to be made different layers. Moreover, additional capacitances are formed by overlapping the scanning signal lines 1 with one parts of the pixel electrodes while interposing insulating films. Similarly, additional capacitances are formed by overlapping the common electrodes 3 with one parts of the pixel electrodes while interposing insulating films.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large screen active matrix type liquid crystal display device having a wide viewing angle and high image quality.

[0002]

2. Description of the Related Art A method of applying an electric field to a liquid crystal composition layer using a comb-like electrode pair formed on one substrate of a conventional active matrix type liquid crystal display device is disclosed in, for example, JP-A-7-36058 and This is proposed by Japanese Patent Application Laid-Open No. Hei 7-159786. Hereinafter, a display method in which the main electric field direction applied to the liquid crystal composition layer is a direction substantially parallel to the substrate interface is referred to as a horizontal electric field method. 1 and 2 show examples of the conventional in-plane switching method. The common electrode and the scanning signal wiring are formed in the same layer. Further, the video signal wiring and the liquid crystal drive electrode are also formed in the same layer. The common electrode and the liquid crystal drive electrode are separately formed in different layers, but are arranged in a linear and parallel comb shape. Similarly, the scanning signal wiring and the video signal wiring are formed in a linear parallel arrangement. The common electrode and the video signal wiring are arranged so as not to overlap. The additional capacitance is formed by overlapping the common electrode and the liquid crystal drive electrode with an insulating film interposed therebetween. The surfaces of the common electrode and the liquid crystal drive electrode, which make up half of the pixel area, are covered with the used metal material as it is, or with a self-oxide film or a self-nitride film to prevent short-circuit.

[0003]

When a liquid crystal display device of the in-plane switching mode is manufactured by the above-mentioned prior art, there is a high probability of a short circuit because the scanning signal wiring and the common electrode are formed in the same layer. Similarly, since the video signal wiring and the liquid crystal drive electrode are also formed in the same layer, there is a high probability of a short circuit. In the former case, a horizontal line defect is generated, and in the latter case, a point defect is generated, which significantly lowers the image quality. For this reason, the conventional structure has a problem that the yield is low and the production cost is high.

In the lateral electric field method, the capacitance of the liquid crystal driving electrode becomes very small unless an additional capacitance is formed.
The non-uniformity of the leakage current of T over the entire screen is likely to be uneven and easy to see. For this reason, in the prior art, the common electrode and the liquid crystal drive electrode are formed separately in different layers via an insulating film, and are formed so as to overlap each other. However, when a large additional capacitance is to be formed, the effective screen is reduced. Thus, there is no other way than to enlarge the area of the superimposed portion, which is a cause of poor light transmittance.

In a conventional lateral electric field system in which a common electrode and a liquid crystal driving electrode are arranged in a linear and parallel comb shape as shown in FIG. 2, the pretilt angle between the alignment film and the liquid crystal is increased as shown in FIG. It is known that it has a great effect on the viewing angle. For this reason, the liquid crystal having a pretilt angle of 3 ° to 8 ° and the alignment film used in the TFT using the conventional TN liquid crystal cannot be used, and when the TN method and the horizontal electric field method are produced by one production line. In addition, the liquid crystal has to be exchanged for the alignment film, and there is a problem that the production efficiency is significantly reduced.

In the lateral electric field method, the aperture ratio is low, and even if it is designed well, it is at most about 50%. Half of the effective screen is covered by the common electrode and the liquid crystal drive electrode,
In the conventional technology, since an anti-reflection film is not formed on the surface of these electrodes, light that has entered the liquid crystal layer through the color filter from the outside is reflected by the common electrode and the liquid crystal driving electrode, and is then recolored. Go outside through the filter. For this reason, there is a problem that the black level of the entire screen is worse than that of the conventional TN liquid crystal system because the black level is increased to the gray side.

The present invention has been made to solve the above-mentioned problems, and has as its object to provide a large-screen high-definition active-matrix liquid crystal display device having a high manufacturing yield, a large aperture ratio and a high contrast at a low cost. To provide.

[0008]

The present invention adopts the following means to solve the above-mentioned problems.

At least a part of a thin film transistor formed on a substrate at each intersection of the scanning signal wiring, the video signal wiring, the scanning signal wiring and the video signal wiring, and a liquid crystal driving electrode connected to the thin film transistor. A liquid crystal display device comprising: an active matrix substrate having a common electrode formed to face the liquid crystal drive electrode; and a liquid crystal layer sandwiched by the facing period plate. [Means 1] The scanning signal wiring and the image The signal wiring, the common electrode, and the liquid crystal drive electrode were formed and separated from each other through an insulating film.

[Means 2] In the means 1, the video signal wiring and at least a part of the common electrode, or the scanning signal wiring and at least a part of the common electrode are overlapped with each other via an insulating film.

[Means 3] In the means 1, at least a part of the liquid crystal drive electrode, the scan signal wiring, and the common electrode is overlapped with each other via an insulating film, and an additional capacitance is formed by the overlapped portion.

[Means 4] In the means 1, when a positive induction anisotropic liquid crystal (P-type LC) is used, the video signal wiring and the pixel electrode (the liquid crystal drive electrode and the common electrode facing the liquid crystal drive electrode) Is ± 1 degree to the liquid crystal alignment direction.
The structure was bent in a range of ± 45 degrees.

[Means 5] In the means 1, when a positive induction anisotropic liquid crystal (P-type LC) is used, the scanning signal wiring and the pixel electrode are arranged at ± 1 degree to ± 1 degree with respect to the liquid crystal alignment direction. 4
The structure was bent in a range of 5 degrees.

[Means 6] In the means 1, in the case of using a liquid crystal having a negative induction rate anisotropic liquid crystal (N-type LC), the video signal wiring and the pixel electrode are at an angle of 45 degrees with respect to the liquid crystal alignment direction. The structure was bent in a range of degrees to 135 degrees.

[Means 7] In the means 1, in the case of using a liquid crystal of negative conductivity anisotropy (N-type LC), the scanning signal wiring and the pixel electrode are positioned at an angle of 45 degrees with respect to the liquid crystal alignment direction. The structure was bent in a range of degrees to 135 degrees.

[Means 8] An antireflection film layer for light is formed on both the liquid crystal drive electrode and the common electrode, or at least one of the electrode surfaces.

[0017]

Since the scanning signal wiring, the video signal wiring, the common electrode, and the liquid crystal driving electrode are present on different layers via the insulating film, respectively, as in the above means 1, the scanning signal wiring and the common electrode are provided. , The probability of occurrence of short circuits is reduced, and horizontal line defects can be reduced. The probability of occurrence of a short circuit between the video signal wiring and the liquid crystal drive electrode is reduced, and the point defect is reduced.

By means 2 and 3, a part of the common electrode and the video signal wiring and the scanning signal wiring can be overlapped with each other via the insulating film, so that the pixel aperture ratio can be increased. Further, since the liquid crystal driving electrode, the scanning signal wiring, and at least a part of the common electrode are overlapped with each other via an insulating film, the added amount can be increased.
It is possible to prevent a decrease in image quality due to a decrease in the FT off-resistance.
Further, since the large amount of addition has an effect of reducing the fluctuation of the liquid crystal driving voltage due to the scanning signal line, the occurrence of an afterimage can be prevented.

As shown in FIGS. 17 and 18 by means 4 to 7 above, when a horizontal electric field is applied within the pixel electrode (liquid crystal drive electrode and common electrode), the liquid crystal molecules are dispersed inside the pixel electrode. , Two kinds of rotational motions, that is, left rotation and right rotation, occur. As shown in FIG. 23, with only one-way rotational movement,
In the case where the pretilt angle is large, the characteristics of the viewing angle are partially different as shown in FIG. In the case where two kinds of rotational movements of liquid crystal molecules, ie, left rotation and right rotation, occur within one pixel electrode, even if the pretilt angle is large, the characteristics of the viewing angle do not occur. For this reason, in the liquid crystal display device using the structure of the present invention, the degree of freedom in selecting the alignment film and the liquid crystal is increased without being restricted by the pretilt angle. The afterimage and the response speed can be easily improved, and a conventional alignment film or liquid crystal can be used, so that the production efficiency can be increased. Since the effective utilization rate of the polarizing plate is increased, the cost d
own.

By means 8 described above, light that has entered the liquid crystal layer through the color filter from the outside is reflected by the antireflection film formed on the common electrode and the liquid crystal drive electrode, as shown in FIG. Since it disappears, the black level is improved and the contrast is increased. An easy-to-view high-quality image is obtained.

According to the above-mentioned means 1, 2 and 3, since there is little leakage of backlight light from areas other than effective pixels, the BM (black mask) area of the color filter can be reduced. 37, 38, 39, 4
By completely covering the TFT portion with a part of the common electrode or a part of the liquid crystal drive electrode as shown in 0, 41 and 42, light from the outside is not directly emitted to the semiconductor active layer of the TFT. This drastically reduces the photo leak current when the TFT is off. The BM (black mask) of the color filter, which has always been required, is no longer required, the manufacturing process of the color filter can be shortened, and the yield can be increased, so that the cost can be reduced.

[0022]

【Example】

[Embodiment 1] FIGS. 3, 4, 5, 31, 31, 35, and 3
FIGS. 6, 37 and 38 show an embodiment of the first class of the present invention.
It is a cross section and a plan view of a unit pixel. Glass substrate ▲ 10 ▼
A common electrode (common electrode) is formed thereon, and a silicon nitride (SiN) film or a silicon oxide (Si)
An underlying insulating film (14) made of an O ₂ ) film or the like was formed.
Next, a scanning signal wiring (gate electrode) was formed. The scanning signal wiring is preferably made of an anodizable metal such as Al, but may be made of a pure metal or an alloy such as Cr, Mo, Ti, W or Ta. A composite metal in which a metal having a low electric resistance value is used and two or three layers are overlapped may be used. After forming a gate insulating film on the scanning signal wiring, the amorphous silicon (a-S
i) A film (T) is formed to be an active layer of a transistor.
A video signal wiring and a drain electrode (D) are formed so as to overlap a part of the amorphous silicon. A protective insulating film made of a SiN film is formed so as to cover all of them.
Next, a through-hole is formed in the SiN on the drain electrode D.
15 is formed. A liquid crystal drive electrode is formed, and is electrically connected to the drain electrode (D) through the through hole (15). An alignment film made of polyimide was formed on the surface of an active matrix substrate in which the unit pixels constituted as described above were arranged in a matrix, and rubbing was performed on the surface. Similarly, a liquid crystal composition containing rod-shaped liquid crystal molecules is sealed between the active matrix substrate and the opposing substrate (11) having an alignment film on the surface of which the rubbing treatment has been performed, and polarized light is applied to the outer surfaces of the two substrates. Boards [12], [13]
▼ was arranged.

The alignment film may be a film which does not require a rubbing treatment and has a liquid crystal alignment by photopolymerization reaction of a photopolymerizable heat-resistant polymer using linearly polarized light.
A pretilt angle is unlikely to occur in the orientation using a photopolymerizable heat-resistant polymer alignment film, but in a horizontal electric field type liquid crystal display mode, a smaller pretilt angle has better viewing angle characteristics. An oriented polymer oriented film can also be used. As shown in FIG. 23, the liquid crystal molecules are oriented so as to have a slight angle (1 degree to 45 degrees) with respect to the longitudinal direction of the striped liquid crystal driving electrode and the common electrode when there is no electric field. The orientation of the liquid crystal molecules at the interface with the upper and lower substrates was parallel to each other. The dielectric anisotropy of the liquid crystal molecules is positive. When a liquid crystal molecule having a negative dielectric anisotropy is used, the axis of the alignment direction of the liquid crystal (P) and the pixel electrode,
May be set in the range of 45 degrees to 89 degrees.

Further, in this embodiment, as shown in FIG. 3, the common electrode and the liquid crystal drive electrode are insulated and separated via the insulating films (14), so that they can be overlapped as shown in FIG. In this case, the overlapping portion can function as an additional capacitor. Further, as shown in FIG. 5, it is possible to superimpose the liquid crystal drive electrode not only on the common electrode but also on the scanning signal wiring. Thus, the additional capacitance can be increased without lowering the aperture ratio. Further FIG.
7. As shown in FIG. 38, the amorphous active layer (T) of the TFT
The liquid crystal drive electrode can be formed so as to cover the entire surface. As shown in FIG. 31, FIG. 35, and FIG. 36, by partially overlapping the common electrode with the scanning signal wiring and the video signal wiring, it is possible to drastically reduce light leakage from other than the effective pixels.

Embodiment 2 FIGS. 6, 7, 8, 9 and 10 are a sectional view and a plan view of a unit pixel according to a second embodiment of the present invention. A scanning signal wiring (gate electrode) is formed on a glass substrate (10), and anodizing is performed.
Anodizable metals are Al, Ta, Nb, and the like. An alloy of these metals may be used, or a gate electrode having a laminated structure may be used. Next, a common electrode (common electrode) is formed, and a gate insulating film covering the common electrode is formed. Subsequent steps are the same as in the first embodiment. In the present invention, the scanning signal wiring (gate electrode)
Has an effect of completely insulating and separating the scanning signal wiring and the common electrode. Thereby, the sheet of the scanning signal wiring and the common electrode can be completely prevented. As in the first embodiment, a part of the common electrode and the video signal wiring can be overlapped. Further, by using a part of the liquid crystal driving electrode, T
It is also possible to completely cover the active layer of the FT.

[Embodiment 3] FIGS. 11, 12 and 13 show
FIG. 9 is a cross-sectional view and a plan view of a unit pixel according to a third class example of the present invention. The scanning signal wiring and the common electrode center line (18) are simultaneously formed on the same layer on the glass substrate (10). Next, after processing so that the common electrode center line (18) and the pixel electrode (20) can be electrically coupled at the contact through hole portion (19), the scanning signal wiring and the common electrode center line (18) are connected to the anode. Perform oxidation treatment. Anodizable metals are
Al, Ta, Nb and the like. An alloy of these metals may be used, or a gate electrode having a laminated structure may be used. Next, the pixel electrodes 20 are formed, and a gate insulating film covering them is formed. Subsequent steps are the same as in the first embodiment. In the present invention, the anodic oxide film of the scanning signal wiring (gate electrode) has a function of completely insulating and separating the scanning signal wiring from the pixel electrode (20) which is a part of the common electrode. The distance between the scanning signal wiring and the common electrode center line (18) is generally very large, and even if they are formed in the same layer, there is almost no short circuit. As in the first embodiment, a part of the common electrode pixel electrode (20) and
It is also possible to superimpose the video signal wiring. Further, it is possible to completely cover the active layer of the TFT by using a part of the liquid crystal drive electrode.

[Embodiment 4] FIGS. 14, 15, 16, 32, 33, 34, 39, 40, 41, 4
2, FIG. 43 and FIG. 44 are a sectional view and a plan view of a unit pixel according to a fourth class example of the present invention. A scanning signal wiring (gate electrode) is formed on a glass substrate (10), a gate insulating film is formed to cover the scanning signal wiring (gate electrode), and then an amorphous silicon (a-Si) film (T) is formed. The active layer of the transistor. Next, the video signal wiring and the drain electrode (D)
To form A protective insulating film made of a SiN film or a SiO ₂ film is formed so as to cover all of them. Next, a through hole (15) is formed on the drain electrode (D). A liquid crystal drive electrode is formed, and is electrically connected to the drain electrode (D) through the through hole (15). Next, after forming an upper insulating film, a common electrode is formed thereon. An alignment film was formed on the surface of an active matrix substrate in which the unit pixels constituted as described above were arranged in a matrix, and rubbing was performed on the surface. In this embodiment, FIG.
As shown in FIG. 4, since the common electrode and the liquid crystal drive electrode are insulated and separated via the insulating film (21), they can be overlapped as shown in FIG. 15, and this overlapped portion acts as an additional capacitor. Can be done. Further, as shown in FIG. 16, it is possible to overlap the liquid crystal drive electrode not only on the common electrode but also on the scanning signal wiring. Thus, the additional capacitance can be increased without lowering the aperture ratio. Next, as shown in FIGS. 39, 40, 41, and 42, a liquid crystal drive electrode and a common electrode can be formed so as to cover the entire surface of the amorphous active layer (T) of the TFT. FIG.
2. As shown in FIGS. 33 and 34, by partially overlapping the common electrode with the scanning signal wiring and the video signal wiring, it is possible to drastically reduce the leakage of light from other than the effective pixels. This makes it possible to use a color filter that does not require a black mask (BM).

Further, in this embodiment, as shown in FIG. 43 and FIG. 44, except for the upper insulating film formed on the liquid crystal drive electrode in the effective pixel, the open window (W)
Can be formed. Thereby, an alignment film can be formed directly on the surfaces of the liquid crystal drive electrode and the common electrode. The liquid crystal is basically driven by an alternating current, and when a bias voltage of a direct current component is applied, the alignment film is polarized or charge is trapped at an interface between the alignment film and the insulating film, so that an afterimage phenomenon occurs. When both electrodes are in direct contact with the alignment film as in the present embodiment, charge traps are small and afterimages are less likely to occur. In the first, second, and third embodiments, FIG.
3, the open window formed in FIG.
It is possible to form ▼.

[Embodiment 5] FIGS. 17, 19, 20, 21, 25, 26, 27, 28, 29 and 3
0 is a plan view of the operation principle of the fifth class and the embodiment.
The dielectric anisotropy of the liquid crystal molecules is positive. The common electrode and the liquid crystal drive electrode inside the pixel are bent within a range of ± 1 degree to ± 45 degrees with respect to the alignment axis (optical axis) (P) of the liquid crystal molecules. In such a structure, when a voltage is applied to the common electrode and the liquid crystal driving electrode and an electric field is generated between the electrodes as shown in FIG. 17, the liquid crystal molecules rotate left and right with respect to the bent portion. It makes two kinds of rotational movements of rotation. The point that two kinds of rotational movements are possible inside the unit pixel has a great effect on the improvement of the viewing angle characteristics. FIG. 19, FIG.
0 and FIG. 21 are plan views of the unit pixel. The feature is that the video signal wiring and the scanning signal wiring are bent in accordance with the bending of the pixel electrode. FIG. 25, FIG. 26, FIG.
FIG. 8 is a plan view of arrangement positions of a common electrode, a liquid crystal drive electrode, a scanning signal wiring, and a video signal wiring when pixels are arranged in a delta arrangement in order to improve the color mixture of the color filters. This delta arrangement is mainly used for AV. FIGS. 29 and 30 are plan views showing the arrangement relationship between the common electrode, the liquid crystal drive electrode, the scanning signal wiring, and the video signal wiring when the pixels are arranged in a stripe arrangement. This stripe arrangement is mainly used for OA.

Embodiment 6 FIGS. 18, 19, 20, 21, 25, 26, 27, 28, 29 and 3
0 is a plan view of the operation principle of the sixth category and the embodiment. The dielectric anisotropy of the liquid crystal molecules is negative. The common electrode and the liquid crystal drive electrode inside the pixel are aligned with the alignment axis (optical axis) of the liquid crystal molecules.
It is bent in the range of 45 to 135 degrees except for 90 degrees with respect to P ▼. As shown in FIG. 18, when a voltage is applied to the common electrode and the liquid crystal driving electrode and an electric field is generated between the electrodes, the liquid crystal molecules are rotated leftward and rightward at the bent portion.
Make a street rotation. This is exactly the same as the fifth embodiment in that the point that two kinds of rotational movements are possible inside the unit pixel is effective in improving the viewing angle characteristics. The plan view structure of the unit pixel and the plan view structure related to the pixel arrangement are the same as those of the fifth embodiment.
Exactly the same. The feature is that the video signal wiring and the scanning signal wiring are bent in accordance with the bending of the pixel electrode. In each of the fifth and sixth embodiments, the rubbing treatment is performed so that the alignment of the liquid crystal molecules at the interface with the upper and lower substrates is parallel to each other. The polarization axis (optical axis) of the polarizing plate is arranged vertically at right and left, and is a normally black mode in which light does not pass from the pixel when no electric field is applied.

[Embodiment 7] FIG. 22 is a sectional view of a seventh embodiment of the present invention. Pixel electrode (common electrode and liquid crystal drive electrode)
An anti-reflection layer is formed on the surface of the liquid crystal display to prevent the light from being reflected by the pixel electrode and coming out again when light from the outside enters the liquid crystal layer. As a typical example, in the case of Cr metal, Cr＼CrN＼CrO or Cr＼
It has a two-layer structure of a nitride film such as CrO and an oxide film or a single-layer structure of only an oxide film. Similarly, in the case of Mo metal, Mo＼M
The structure of oN @ MoO or Mo @ MoO is used. In addition, a considerable antireflection effect can be obtained by coating the surface of the pixel electrode with an a-Si layer or by coating carbon. Cr @ CrSix, Mo @ MoSix,
Ti＼TiSix, W＼WSix Ta＼TaSix,
Metal silicide such as Nb＼NbSix can also be used because it has an antireflection effect.

Further, as shown in FIG. 45, the same effect can be obtained by forming an antireflection film layer on the insulating film on the pixel electrode. In this case, an antireflection film of an insulating film is suitable. a
-Si layer, a blue pigment-based resist used for a color filter, a black pigment-based resist, or the like can be used.

In the case of a color filter having no black mask on the counter substrate (11), an antireflection film layer is formed on the surface of the scanning signal electrode or the video signal electrode as shown in FIG. An in-plane switching mode liquid crystal display device with very good contrast can be manufactured.

[0034]

As described above, according to the present invention, the scanning signal wiring, the video signal wiring, the common electrode, and the liquid crystal drive electrode are separately formed by insulating films, respectively, so that no short circuit occurs. A liquid crystal panel with a high aperture ratio and high contrast with little afterimage can be made. Furthermore, by bending the pixel electrode with respect to the liquid crystal alignment direction, a rotation direction of two liquid crystal molecules can be created in a unit pixel, and the viewing angle can be increased. The cost can be reduced because the alignment material conventionally used can be used.

[Brief description of the drawings]

FIG. 1 is a sectional view of a conventional lateral electric field type unit pixel.

FIG. 2 is a plan view of a conventional lateral electric field type unit pixel.

FIG. 3 is a cross-sectional view of a lateral electric field type unit pixel of the present invention (Example 1).

FIG. 4 is a plan view of a lateral electric field type unit pixel of the present invention (Example 1).

FIG. 5 is a sectional view of a lateral electric field type unit pixel according to the present invention (Example 1).

FIG. 6 is a plan view of a lateral electric field type unit pixel according to the present invention (Example 2).

FIG. 7 is a plan view of a lateral electric field type unit pixel of the present invention (Example 2).

FIG. 8 is a plan view of a lateral electric field type unit pixel according to the present invention (Example 2).

FIG. 9 is a plan view of a lateral electric field type unit pixel of the present invention (Example 2).

FIG. 10 is a plan view of a lateral electric field type unit pixel of the present invention (Example 2).

FIG. 11 is a cross-sectional view of a lateral electric field type unit pixel of the present invention (Example 3).

FIG. 12 is a plan view of a lateral electric field type unit pixel of the present invention (Example 3).

FIG. 13 is a plan view of a lateral electric field type unit pixel of the present invention (Example 3).

FIG. 14 is a cross-sectional view of a lateral electric field type unit pixel according to the present invention (Example 4).

FIG. 15 is a plan view of a lateral electric field type unit pixel according to the present invention (Example 4).

FIG. 16 is a plan view of a lateral electric field type unit pixel according to the present invention (Example 4).

FIG. 17 is a view showing an orientation direction of a positive dielectric anisotropy liquid crystal in a lateral electric field bending pixel electrode of the present invention (Example 5).

FIG. 18 is a view showing the orientation direction of a negative dielectric anisotropy liquid crystal in a lateral electric field type bent pixel electrode of the present invention (Example 6).

FIG. 19 is a plan view of a lateral electric field type unit pixel according to the present invention (Examples 5 and 6).

FIG. 20 is a plan view of a lateral electric field type unit pixel according to the present invention (Examples 5 and 6).

FIG. 21 is a plan view of a lateral electric field type unit pixel according to the present invention (Examples 5 and 6).

FIG. 22 is a cross-sectional view of a pixel electrode with an anti-reflection film according to the present invention (Example 7).

FIG. 23 is a view showing an alignment direction of a positive liquid crystal ratio anisotropic liquid crystal in a lateral electric field type pixel electrode (Example 1, Example 2, Example 3, Example 4).

FIG. 24 shows a pretilt angle and a viewing angle characteristic of liquid crystal molecules of an in-plane switching mode liquid crystal display device.

FIG. 25 is a plan view of a lateral electric field type pixel array of the present invention (Embodiments 5 and 6).

FIG. 26 is a plan view of a lateral electric field type pixel array according to the present invention (Examples 5 and 6).

FIG. 27 is a plan view of a lateral electric field type pixel array of the present invention (Embodiments 5 and 6).

FIG. 28 is a plan view of a lateral electric field type pixel array according to the present invention (Examples 5 and 6).

FIG. 29 is a plan view of a lateral electric field type pixel array according to the present invention (Examples 5 and 6).

FIG. 30 is a plan view of a lateral electric field type pixel array of the present invention (Embodiments 5 and 6).

FIG. 31 is a sectional view of an overlapping portion of a common electrode and a video signal wiring according to the present invention (Example 1).

FIG. 32 is a sectional view of a superposed portion of a common electrode and a video signal wiring according to the present invention (Example 4).

FIG. 33 is a sectional view of a superposed portion of a common electrode, a liquid crystal drive electrode, and a scanning signal line according to the present invention (Example 4).

FIG. 34 is a sectional view of a superposed portion of a common electrode, a liquid crystal drive electrode, and a scanning signal line according to the present invention (Example 4).

FIG. 35 is a sectional view of a superposed portion of a common electrode, a liquid crystal drive electrode, and a scanning signal line according to the present invention (Example 1).

FIG. 36 is a sectional view of a superposed portion of a common electrode, a liquid crystal driving electrode, and a scanning signal line according to the present invention (Example 1).

FIG. 37 is a cross-sectional view in which an active layer of a transistor portion is interposed between a scanning signal wiring and a liquid crystal driving electrode of the present invention (Example 1).

FIG. 38 is a plan view of a lateral electric field type unit pixel of the present invention (Example 1).

FIG. 39 is a cross-sectional view in which an active layer of a transistor portion is interposed between a scanning signal wiring and a liquid crystal drive electrode according to the present invention (Example 4).

FIG. 40 is a plan view of a lateral electric field type unit pixel according to the present invention (Example 4).

FIG. 41 is a cross-sectional view in which an active layer of a transistor portion is interposed between a scanning signal wiring and a liquid crystal driving electrode of the present invention (Example 4).

FIG. 42 is a plan view of a lateral electric field type unit pixel according to the present invention (Example 4).

FIG. 43 is a cross-sectional view of a lateral electric field type unit pixel of the present invention (Example 4).

FIG. 44 is a plan view of a lateral electric field type unit pixel of the present invention (Example 4).

FIG. 45 is a sectional view of a pixel electrode with an in-plane switching type antireflection film according to the present invention (Example 7).

[Explanation of symbols]

1—Scan signal wiring 2—Video signal wiring 3—Common electrode 4—Liquid crystal drive electrode 5—Gate insulating film 6—Protective insulating film 7—TFT substrate-side alignment film 8—Counter substrate-side alignment Film 9—Liquid crystal molecules (positive dielectric anisotropic liquid crystal) 10—TFT side glass substrate 11—Opposite glass substrate 12—TFT side polarizing plate 13—Optical substrate side polarizing plate 14—Base insulating film 15—Drain through hole 16—Storage capacitance forming area 17—Anodic oxide film 18—Common electrode (center line) formed simultaneously with the same material as scanning signal wiring 19—Common electrode through hole 20—Common Pixel electrode in contact with common electrode (center line) through electrode through hole 21-Upper insulating film 22-Visible light antireflection film 23-Liquid crystal molecules (negative dielectric anisotropy liquid crystal) 3-F- Same material as common electrode A—The angle at which the alignment direction of the P-type liquid crystal molecules intersects with the pixel electrode (common electrode and liquid crystal drive electrode) B—The alignment direction of the N-type liquid crystal molecules and the pixel electrode (common electrode and liquid crystal) Angle at which drive electrode intersects P-orientation direction of liquid crystal molecules and polarization axis direction of optical plate (optical axis) Q-polarization axis direction of optical plate (optical axis) D-formed simultaneously with video signal wiring Transistor drain electrode T-semiconductor layer W-LCD drive electrode open window

Claims (8)

[Claims] At least one of a scanning signal wiring and a video signal wiring on a substrate, a thin film transistor formed at each intersection of the scanning signal wiring and the video signal wiring, and a liquid crystal drive electrode connected to the thin film transistor. A liquid crystal layer sandwiched between the active matrix substrate, a counter substrate facing the active matrix substrate, and a liquid crystal layer sandwiched by the counter substrate. In the liquid crystal display device, the scanning signal wiring, the video signal wiring, the common electrode and the liquid crystal driving electrode are formed and separated in different layers via an insulating film, respectively. Display device. 2. The image signal wiring according to claim 1, wherein at least a part of the video signal wiring and the common electrode or at least a part of the scanning signal wiring and the common electrode are overlapped with each other via an insulating film. A liquid crystal display device characterized by the above-mentioned. 3. The liquid crystal driving electrode according to claim 1, wherein at least a part of the liquid crystal driving electrode and the scanning signal wiring and the common electrode are overlapped with each other via an insulating film, and an additional capacitance is formed by the overlapping portion. A liquid crystal display device characterized by the above-mentioned. 4. The liquid crystal display device according to claim 1, wherein the video signal wiring and the pixel electrode (the liquid crystal driving electrode and a part of the common electrode facing the liquid crystal driving electrode) are ± 1 with respect to the liquid crystal alignment direction. A liquid crystal display device characterized by a structure arrangement that is bent in an angle range of degrees to ± 45 degrees. 5. The liquid crystal display according to claim 1, wherein the scanning signal wiring and the pixel electrode are arranged at an angle of ± 1 degree with respect to a liquid crystal alignment direction.
A liquid crystal display device characterized by a bent structural arrangement in an angle range of ± 45 degrees. 6. A structure according to claim 1, wherein the video signal wiring and the pixel electrode are bent in a range of 45 ° to 135 ° except 90 ° with respect to a liquid crystal alignment direction. Liquid crystal display device. 7. A structure according to claim 1, wherein the scanning signal wiring and the pixel electrode are bent in a range of 45 ° to 135 ° except 90 ° with respect to a liquid crystal alignment direction. Liquid crystal display device. 8. A scanning signal wiring, a video signal wiring, a thin film transistor formed at each intersection of the scanning signal wiring and the video signal wiring on a substrate, a liquid crystal driving electrode connected to the thin film transistor, An active matrix substrate having a common electrode at least partially opposed to the liquid crystal drive electrode, a counter substrate facing the active matrix substrate, and a liquid crystal layer sandwiched between the active matrix substrate and the counter substrate A liquid crystal display device comprising: a liquid crystal display device comprising: a light reflection preventing film layer formed on both the common electrode and the liquid crystal driving electrode or at least one electrode surface.