JPH08254706A - Liquid crystal display device - Google Patents

Abstract

PURPOSE: To make it possible to obtain a display uniform over the entire surface without projection of discrination into pixel openings by stabilizing liquid crystal orientation in respective divided regions of a liquid crystal display device varying in the orientation state of liquid crystals with each of the microregions. CONSTITUTION: Pixel electrodes 71 are provided with notches 74 in alignment to the positions at boundaries 22 of orientation treatment sections or the spacings between the side of the pixel electrodes and gate bus lines 55 or drain bus lines 56 along these sides are varied on both sides of the boundaries 22 of the orientation treatment sections.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device in which the alignment state of liquid crystal is made different for each minute region.

[0002]

2. Description of the Related Art A liquid crystal display device (LCD) generally has a structure in which liquid crystal is inserted between a pair of opposed substrates. In the twisted nematic type liquid crystal display device,
Two substrates each having an alignment film provided on the substrates are used, and a polarizing plate is arranged outside each of the substrates. The liquid crystal molecules are oriented in a spiral shape so that they are twisted from one substrate to the other, while the longitudinal direction of the liquid crystal molecules is substantially parallel to both substrates. The orientation directions of the molecules are almost perpendicular to each other. In addition, liquid crystal molecules near both surfaces of each substrate can be pretilted. That is, the longitudinal direction of the liquid crystal molecules can be slightly tilted from the parallel to the substrate.
The alignment direction and pretilt direction of the liquid crystal molecules near the surface of each substrate are determined according to the material of the alignment film and the rubbing direction with respect to the alignment film. The alignment direction and pretilt direction of liquid crystal molecules near the surface of each substrate can also be controlled by forming an alignment film by oblique vapor deposition. Here, the direction of the pretilt is the direction of the end portion of the liquid crystal molecule that rises away from the substrate, in the direction of both end portions.

In such a twisted nematic liquid crystal display device, when a voltage is applied to the liquid crystal layer, the twisted and aligned liquid crystal molecules rise in a direction perpendicular to the substrate. Then, the transmittance of incident light can be changed by the change of the alignment state. The rising angle of the liquid crystal molecules changes depending on the magnitude of the applied voltage, and by controlling the magnitude of this voltage, gradation display from the bright state to the dark state can be performed. Recently, a type of liquid crystal display device (so-called active matrix type liquid crystal display device: AM-LCD) in which pixels are arranged in a vertical and horizontal matrix and each pixel is driven by an active element has become widespread. In an active matrix type liquid crystal display device, active elements are provided near the intersections of a plurality of gate bus lines running in the vertical and horizontal directions and drain bus lines, and transparent pixels provided in the area surrounded by these bus lines. A desired voltage can be applied to the electrodes to hold the voltage. In addition, in the active matrix type liquid crystal display device, it is often performed to connect the storage capacitor in parallel with the pixel capacitance in order to more efficiently hold the voltage applied to the pixel. At this time, the storage capacitor terminal connected to the pixel electrode is overlapped on the gate bus line different from the gate bus line connected to the active element for driving the pixel so as to project through the insulating layer. This is an effective means because the electrode layer structure can be simplified, the process can be simplified, and the storage capacitor can be provided without lowering the pixel aperture ratio.

As described above, in the twisted nematic liquid crystal display device, gradation display from the bright state to the dark state can be performed by controlling the voltage applied to the liquid crystal layer. However, since the brightness of each gradation changes depending on the viewing direction of the screen, there is a problem that the visual range in which the display can be accurately recognized is narrow. That is, the display becomes whitish when viewed from a certain direction,
When viewed from the opposite direction, the entire display is blackened or the gradation is inverted.

The change in the gradation characteristics due to such a visual sense is
This is due to the asymmetry of the alignment state of the liquid crystal molecules. The rising direction of the liquid crystal molecules when a voltage is applied to the liquid crystal layer is determined by the pretilt direction and the direction of the applied electric field. Since the direction of the electric field is substantially perpendicular to the substrate, the liquid crystal molecules stand up according to the pretilt direction, that is, the direction of the liquid crystal alignment process. Further, since the rising angle of the liquid crystal molecules changes depending on the applied voltage, the gradation display as described above can be performed by controlling the magnitude of this voltage. The movement of the liquid crystal molecules due to the applied voltage is small near the surface of both substrates and large near the center between both substrates. Therefore, the rising angle of the liquid crystal molecules existing near the central portion between both substrates with respect to the substrate mainly contributes to the brightness of the display. In the state where the liquid crystal molecules near the central portion between the two substrates stand up at a certain angle with respect to the substrate surface, that is, in the halftone display state, the screen appears when the liquid crystal display device is observed from the rising direction of the liquid crystal molecules. Looks whitish, and when viewed from the opposite direction, it looks black.

In order to solve the problem of the visual dependence of the gradation characteristics and to secure a wide viewing angle, Japanese Patent Publication No. 58-4.
Japanese Patent No. 3723 discloses a structure in which regions having different liquid crystal alignment treatment directions are formed at a fine pitch. In the structure according to Japanese Patent Publication No. 58-48723, the rising direction of the liquid crystal molecules when a voltage is applied is different for each minute area, so that the observer recognizes that the viewing angle characteristics of each minute area are averaged. And as a result,
The viewing angle characteristics are improved.

By the way, when a plurality of minute regions having different rising directions of liquid crystal molecules are provided, an alignment defect called disclination is generated at the boundary between the regions having different rising directions of liquid crystal molecules, resulting in contrast. And other problems occur. In order to prevent deterioration of image quality due to disclination, it is necessary to provide a light-shielding portion in alignment with the position where disclination occurs. For this purpose, it is necessary to realize stable liquid crystal alignment in which the position of disclination is accurately controlled. However, the rising direction of the liquid crystal molecules is influenced by the regulation force due to the liquid crystal alignment treatment, and in the case of the active matrix type liquid crystal display device as described above, the rising direction of the gate bus line and the drain bus line and the pixel electrode Since it is also affected by the lateral electric field between them, it is not easy to accurately control the rising direction of the liquid crystal molecules and hence the position of the disclination. When the liquid crystal display device becomes high-definition and the distance between the pixel electrode and the gate bus line / drain bus line becomes small accordingly, the lateral electric field generated between the pixel electrode and the gate bus line / drain bus line also becomes large and stable. It is less easy to achieve a split orientation. In such a case, the disclination may be displaced from the original boundary position of the alignment treatment section, or may be gradually moved to another position after it is generated, so that the disclination is provided in alignment with the boundary position of the alignment treatment section. Out of the light shield
Image quality deteriorates.

When the disclination occurs at the boundary position of the alignment processing section, a reverse tilt domain, that is, a domain in which liquid crystal molecules stand up in a direction different from the alignment processing direction is generated. Or conversely, it can be said that the occurrence of the reverse tilt domain causes the disclination to shift from a predetermined position, resulting in deterioration of image quality. Among the parts on the pixel electrode, the part where such a reverse tilt domain is likely to occur is, in each minute region where the alignment state of liquid crystal molecules is different, in the vicinity of each side or each corner of the pixel electrode or on the pixel electrode. In a direction different from the "substantial pretilt direction" on the surface of the substrate on which the pixel electrode, the gate bus line, or the drain bus line is provided, which is in the vicinity of the boundary of the alignment treatment section set to It is a part to be located. This is because the "substantial pretilt direction" does not coincide with the direction of the lateral electric field at this portion. Here, the "substantial pretilt direction" on the surface of the substrate means the alignment direction of the liquid crystal molecules from the vicinity of the central portion between the two substrates to the surface of the substrate among the both ends of the liquid crystal molecules near the surface of the substrate. Of the liquid crystal molecules in the vicinity of the central portion between the two substrates, the direction corresponding to the edge that rises away from the substrate when a voltage is applied. The "substantial pretilt direction" on the substrate surface generally coincides with the pretilt direction on the substrate surface, but in the case of so-called splay type liquid crystal alignment in which the pretilt directions do not match between the two substrates, they may not match.

In order to obtain a good alignment at the boundary of the alignment treatment section, in JP-A-5-173142, the portion of the alignment film corresponding to the boundary of the alignment treatment section protrudes or retreats in the thickness direction of the liquid crystal. A configuration formed in a deformed shape, a configuration in which liquid crystals of each alignment treatment section are both arranged to pretilt toward the gate bus line in the vicinity of the substrate provided with the gate bus line, and Disclosed is a configuration in which each pixel is composed of divided pixel electrodes divided through a minute gap, and the boundary portion of the alignment processing section is aligned with this gap. In the configuration characterized by the deformed shape, the tendency that the liquid crystal molecules are aligned along the irregularities on the surface of the alignment film acts to assist the predetermined alignment, and the pre-tilt is performed toward the gate bus line. In this configuration, the lateral electric field around the gate bus line acts so as to assist a predetermined orientation, and in the configuration characterized by the divided pixel electrodes of, the lateral electric field between the divided pixel electrodes has a predetermined orientation. It acts to help.

However, among the configurations disclosed in Japanese Patent Laid-Open No. 5-173142, which is characterized by the deformed shape, both substrates are provided with irregularities of a sufficient size to assist the predetermined liquid crystal alignment. In order to form it on the surface of, it is necessary to add a new step, which leads to an increase in cost, which is not preferable. Although existing gate bus lines and drain bus lines can be used to form the unevenness, this method cannot be applied to, for example, the boundary of the alignment processing section set on the pixel electrode. Not only that, but when the concave portion or the convex portion is provided, the rubbing treatment may not be performed well in a portion that is shaded by the concave portion or the convex portion when the rubbing treatment is performed, which may rather make the orientation unstable.

In the structure disclosed in Japanese Unexamined Patent Publication No. 5-173142, which is characterized in that the pre-tilt is performed toward the gate bus line, for example, the boundary of the alignment processing section set on the pixel electrode. The liquid crystal orientation in the vicinity of is not stabilized. Further, when the liquid crystal display device is further refined and the liquid crystal molecules on the pixel electrodes are easily affected by the lateral electric field around the gate bus lines, the alignment may be disturbed. This is because, just above the gate bus line, the electric field is applied laterally in the direction of raising the liquid crystal molecules toward the outside of the gate bus line, so that the liquid crystal alignment directly above the gate bus line is disturbed, and this effect is This is because it may reach the liquid crystal molecules on the pixel electrode.

Further, among the configurations disclosed in Japanese Unexamined Patent Publication No. 5-173142, in the configuration featuring the divided pixel electrodes, it is necessary to provide a driving means composed of an active element such as a thin film transistor for each divided pixel electrode. Therefore, not only the pixel aperture ratio but also the yield may be reduced.

[0013]

As described above, in the liquid crystal display device in which the alignment treatment is performed by dividing into minute regions for the purpose of expanding the viewing angle, the liquid crystal alignment is stable in each divided region. Without this, the disclination may be generated from the original boundary position of the alignment treatment section, or may gradually move to another position after the generation, resulting in a decrease in contrast ratio and uneven display on the entire surface. However, there is a problem that image sticking or image sticking may occur.

The object of the present invention is to stabilize the liquid crystal alignment in each divided area in a liquid crystal display device in which the alignment state of the liquid crystal is different for each minute area, so that the disclination is separated from the boundary of the alignment treatment section. An object of the present invention is to provide a liquid crystal display device which is accurately fixed at a predetermined position without being displaced and which can obtain a uniform and excellent display over the entire surface. Needless to say, it is not preferable that other problems such as complication of the process, reduction of the pixel aperture ratio, reduction of the yield, etc. are accompanied in order to realize this.

[0015]

A liquid crystal display device according to the present invention includes a first substrate and a second substrate which are provided to face each other.
Pixel electrodes provided in a matrix on the first substrate, active elements provided on the first substrate for each pixel electrode to drive corresponding pixel electrodes, and active elements provided on the first substrate. A gate bus line and a drain bus line connected to each other, a common electrode provided on the second substrate, and a liquid crystal inserted between the first substrate and the second substrate. In a liquid crystal display device in which at least one of a first substrate and a second substrate is subjected to an alignment treatment corresponding to the minute region so that the alignment state is different for each minute region, the pixel electrode is crossed. At least one of the boundaries of the alignment processing section is set at the position, and the planar shape of the pixel electrode has a cut portion aligned with the boundary of the alignment processing section that crosses the pixel electrode.
Alternatively, the distance between the pixel electrode and the gate bus line or the drain bus line along the side of the pixel electrode is different on both sides of the boundary of the alignment treatment section that crosses the pixel electrode, or both of them.

In the present invention, the disclination can be concealed by providing the light-shielding portion in alignment with the boundary position of the alignment processing section that crosses the pixel electrode. Further, in the case where the pixel electrode is provided with a cut portion, it is possible to provide a division preventing terminal in order to prevent the pixel electrode from being divided at that portion. These light-shielding portions or division preventing terminals may be formed of the same thin film layer that forms the gate bus line or the drain bus line.

Further, in the present invention, the alignment treatment is performed on both sides of the boundary of the alignment treatment section which crosses the pixel electrode so that the liquid crystal molecules stand up at the end on the boundary side when a voltage is applied in a direction away from the first substrate. It can be carried out. In this case, the shape of the cutout portion of the pixel electrode is defined as the shape of the liquid crystal molecule in the vicinity of the position where the boundary crosses the side of the pixel electrode among the parts on the pixel electrode and in the vicinity of the first substrate. If the portion located in the longitudinal direction is cut out, the disclination can be fixed at an extremely accurate position. Alternatively, in the present invention, on both sides of the boundary of the alignment processing section that crosses the pixel electrode, the end portion on the opposite side to this boundary when voltage is applied,
The alignment treatment can be performed so that the liquid crystal molecules rise in a direction away from the first substrate. In this case, the shape of the cut portion of the pixel electrode may be an elongated shape such that the longitudinal direction of the cut portion is located along this boundary. The elongated cut portion may have a shape such that an elongated hole is formed in the pixel electrode or a shape in which the pixel electrode is cut from one side or both sides along the boundary. When the pixel electrode has a shape cut from one side or both sides, chamfering the corner of the pixel electrode attached to the cut portion can fix the disclination at an extremely accurate position.

Further, a boundary of the alignment treatment section is set between the pixel electrodes, and liquid crystal molecules are formed on both sides of the boundary in a direction in which an edge portion on the boundary side separates from the first substrate when a voltage is applied. Alignment treatment can be performed so as to rise. In this case, the boundary of the alignment processing section may be set between the pixel electrode and the gate bus line. Alternatively, a boundary of an alignment treatment section is set between the pixel electrode and the pixel electrode, and liquid crystal molecules are formed on both sides of the boundary in a direction in which an end opposite to the boundary is separated from the first substrate when a voltage is applied. Alignment treatment can be performed so as to rise. In this case, the boundary of the alignment treatment section may be set on the gate bus line.

When the distance between the side of the pixel electrode and the gate bus line or the drain bus line along the side is different on both sides of the boundary of the alignment treatment section that crosses the pixel electrode, the surface of the first substrate In a portion located in the direction opposite to the “substantial pretilt direction” of the liquid crystal molecules in the vicinity, the distance between the side of the pixel electrode and the gate bus line or drain bus line along the side is in the other portion. It should be larger than.

[0020]

In the liquid crystal display device of the present invention, the pixel electrode is provided with the notch aligned with the boundary position of the alignment processing section which crosses the pixel electrode, or the side of the pixel electrode and the gate bus along the side. Since the distance from the line or the drain bus line is different on both sides of the boundary of the alignment processing section that crosses the pixel electrode, a lateral electric field that may influence the rising direction of liquid crystal molecules on the pixel electrode when a voltage is applied. Can be weakened or the lateral electric field can be positively used to accurately fix the position of the disclination at a predetermined position. Therefore, the disclination does not extend into the pixel opening and deteriorates the image quality, and a uniform and good display can be obtained on the entire surface. Further, according to the present invention, the great effect as described above can be obtained only by changing the shape of the pixel electrode without adding a new process to the whole manufacturing process.

[0021]

Embodiments of the present invention will now be described with reference to the drawings.

Example 1 FIG. 1 is a plan view showing the structure of the liquid crystal display device of Example 1, and FIG. 2 is a sectional view showing the structure near the gate bus line in the liquid crystal display device of FIG. . Broadly speaking, this liquid crystal display device has a structure in which a first substrate 11 and a second substrate 12 are superposed so as to keep a constant space, and a liquid crystal 20 is injected between both substrates 11 and 12. There is. Polarizing plates (not shown) are arranged outside the substrates 11 and 12, respectively. In FIG. 1, the first substrate 11 is arranged on the back side and the second substrate 12 is arranged on the front side with respect to the paper surface.

On the first substrate 11, a plurality of gate bus lines 55 extending parallel to each other in the horizontal direction in the drawing and a plurality of drain bus lines 56 extending parallel to each other in the vertical direction in the drawing are arranged in a grid pattern. The pixel electrode 71 is provided so as to be surrounded by the gate bus line 55 and the drain bus line 56 for each unit lattice. The gate bus line 55 and the drain bus line 56 are each formed of a conductive thin film layer made of a material such as chromium,
The pixel electrode 71 is composed of a transparent conductive thin film layer made of a material such as indium tin oxide (ITO). The conductive thin film layer that forms the gate bus line 55 and the conductive thin film layer that forms the drain bus line 56 and the transparent conductive thin film layer that forms the pixel electrode 71 are insulated by the insulating layer 57. Each pixel electrode 71 corresponds to one pixel. Further, the active element 54 is provided for each pixel electrode 71. The active element 54 is a switch element for selecting the pixel electrode 71 and applying a voltage thereto, and is typically a thin film transistor (amorphous silicon (a-Si) or polycrystalline silicon (p-Si)). TFT). The gate terminal of the active element 54 is the gate bus line 5
5, the drain terminal is connected to the drain bus line 56.
, And the source terminal is connected to the pixel electrode 71. Further, a storage capacitor terminal 58 is provided for each pixel electrode 71. The storage capacitor terminal 58 is formed of the same thin film layer as the conductive thin film layer forming the drain bus line, and is electrically connected to the pixel electrode 71. A part of the storage capacitor terminal 58 has a gate bus line 55 to which an active element 54 for driving an adjacent pixel electrode 71 is connected.
The storage capacitor portion 25 is formed so as to overhang the insulating layer 57 (see FIG. 2). An alignment film 31 is formed on the outermost surface of the first substrate 11 that is in contact with the liquid crystal 20.

On the other hand, the common electrode 72 is formed on the second substrate 12.
And the alignment film 32 are laminated in this order.
Is in contact with the liquid crystal 20. The common electrode 72 is composed of a transparent conductive thin film layer made of a material such as indium tin oxide (ITO). Further, on the second substrate 12, a color filter (not shown) made of R, G, and B corresponding to each pixel electrode 71 is provided. Therefore, the liquid crystal display device of the first embodiment can perform color display as a whole. Further, a light shielding film (not shown) is provided on the second substrate 12 in a region other than the region corresponding to the pixel electrode 71.

In the liquid crystal display device according to the first embodiment,
The size of the pitch in which the pixel electrodes 71 are arranged in a matrix is 67 μm in the extending direction of the gate bus lines 55 and 201 μm in the extending direction of the drain bus lines 56. The first substrate 11 and the second substrate 12 are laminated facing each other so as to keep a distance of about 6 μm from each other.

In this embodiment, the first and second substrates 1
1, 12 are oriented in different directions in each of the strip-shaped regions indicated by A and B in FIG. The first substrate 11 is oriented in the directions indicated by arrows 111a and 111b, and the second substrate 12 is oriented in the directions indicated by 112a and 112b. A boundary 22 (an alternate long and short dash line in the figure) between the regions A and B is a straight line parallel to the extending direction of the gate bus line 55, and a position that crosses substantially the center of each pixel electrode 71, each pixel electrode 71 and its pixel. It is set to a position between the gate bus line 55 to which the active element 54 for driving the electrode is connected.

As described above, in order to perform the orientation treatment in different directions for each minute region on the same substrate, as shown in FIG.
Each step shown in (e) may be sequentially performed. First, Fig. 3
As shown in (a), alignment films 31 and 32 made of an alignment agent such as polyimide are formed on the surfaces of the substrates 11 and 12 on which electrodes and bus lines are formed. Next, as shown in FIG. 3B, a rubbing process is performed in a fixed direction. The rubbing process is performed by advancing the rubbing roller 80 wound with a puff cloth such as rayon while rotating on the alignment films 31 and 32. Subsequently, as shown in FIG. 3C, a resist 40 is applied on the alignment films 31 and 32, and a resist pattern is formed by photolithography technique so as to correspond to either the region A or the region B of FIG. Form. Then, as shown in FIG.
The rubbing process is performed in the direction opposite to the direction shown in (b). Finally, as shown in FIG. 3E, the resist 40 is removed using an organic solvent. As a result, the substrates 11 and 1 in which the minute regions A and B are oriented in different directions
2 can be obtained. In Example 1, as an aligning agent, SE-7210 (06 manufactured by Nissan Chemical Industries, Ltd.) was used.
21) was used in a normal use method, a normal positive resist was used as a resist, and acetone was used for removing the resist.

In the first embodiment, the liquid crystal 20 contains
E. FIG. ZLI-4 from Merck, Darmetadt
792 was used. A small amount of a counterclockwise chiral agent is added to this liquid crystal material. According to the effect of the chiral agent and the above-described alignment treatment direction, the liquid crystal molecules are arranged such that the front surface of the second substrate 12 in FIG.
The surface is twisted and oriented in a counterclockwise direction at a right angle toward the surface. In addition, the liquid crystal molecules near the surfaces of both substrates 11 and 12 are pretilted in the direction of the tip of the arrow indicating the orientation processing direction in FIG. 1 according to the orientation processing direction described above. That is, the regions A and B in FIG. 1 are pretilted in different directions. Therefore, when a voltage is applied, the rising directions of the liquid crystal molecules are different between the regions A and B.

In the liquid crystal display device of the first embodiment, in order to prevent light leakage from the disclination portion, the pixel electrode 7
The light-shielding portion 26 is provided on the first substrate on which 1 is provided. The light-shielding portion 26 is formed of the same thin film layer as the conductive thin film layer that forms the gate bus line, and of the boundary 22 of the alignment processing section, the boundary of the alignment processing section that crosses substantially the center of the pixel electrode 71. It is provided to match the position. The light shielding portion 26 is electrically insulated from the pixel electrode 71 by the insulating layer 57.

Further, the liquid crystal display device of the first embodiment has the cutouts 74 in the planar shape of each pixel electrode 71. The notch 74 is provided at the boundary 22 of the alignment processing section.
Among them, the pixel electrode 71 is provided so as to be aligned with the position of the boundary of the alignment processing section that crosses substantially the central portion. Further, the shape of the cut portion 74 is such that in each of the regions A and B,
The shape is such that a portion of the portion on the pixel electrode where the reverse tilt domain is likely to occur is cut out. Specifically, the portion of the pixel electrode 71 near the surface of the first substrate 11 located in the direction opposite to the pretilt direction of the liquid crystal molecules, that is, in the first embodiment, the orientation with respect to the first substrate 11 in FIG. As shown in FIG. 1, a portion located behind the processing direction arrows 111a and 111b is a right angle 2 with a hypotenuse being a straight line substantially orthogonal to the orientation processing direction arrows.
It is a shape cut out in the shape of an equilateral triangle. Notch 74
The size of 3 is 6 μm, 12 μm and 18 μm with respect to the length of the hypotenuse of the notch of the isosceles right triangle.
Conducted on seeds.

Next, the position where disclination occurs in the liquid crystal display device according to the first embodiment will be described with reference to FIGS. 1 and 2.

First, the position where disclination occurs along the boundary of the alignment processing section that crosses the substantially central portion of the pixel electrode 71 will be described with reference to FIG. In this liquid crystal display device, in the planar shape of the pixel electrode 71, a portion on the pixel electrode where a reverse tilt domain is likely to occur, that is, in the vicinity of the intersection of the side of the pixel electrode 71 and the boundary 22 of the alignment processing section. Also, since the portion of the surface of the first substrate 11 located in the direction opposite to the pretilt direction is cut off, the lateral electric field applied to the liquid crystal layer at that portion is weakened, and the disclination 23 is It is fixed at a predetermined position, that is, the position of the boundary 22 of the alignment processing section.

Next, the pixel electrode 71 and the gate bus line 5
5 with the boundary 22 of the orientation treatment section set between 5 and
The position where the disclination occurs will be described with reference to FIG. FIG. 2 is a cross-sectional view of a cross section orthogonal to the extending direction of the gate bus line 55, showing a portion including the boundary 22 of the alignment processing section set between the pixel electrode 71 and the gate bus line 55. In FIG. 2, the electric field direction is indicated by a dotted line. In this liquid crystal display device, the boundary 22 of the alignment processing section is set between the pixel electrode 71 and the gate bus line 55, and the liquid crystal molecules 21 have gates on both sides of the alignment processing section on the boundary side. Since the alignment treatment is performed so as to rise in the direction away from the first substrate provided with the bus line 55, the direction of the electric field applied to the liquid crystal layer coincides with the pretilt direction, and the disclination 23 has a predetermined position. That is, it is fixed at the position of the boundary 22 of the liquid crystal alignment processing section.

As described above, the disclinations associated with the boundaries 22 of the orientation-processed sections are fixed at predetermined positions, respectively. Therefore, as shown in FIG. 1, the disclinations 23 are fixed at predetermined positions as a whole. As a result, it was confirmed that the liquid crystal display device did not protrude into the pixel opening and that a uniform and good image quality was obtained over the entire surface of the liquid crystal display device. This was confirmed in each of the above-mentioned three sizes of cuts.

<< Comparative Example 1 >> A liquid crystal display device having the same structure as that of Example 1, but the planar shape of each pixel electrode 71 different from that of Example 1, was manufactured. That is, the pixel electrode 71
Has no cut portion in its planar shape, and the portion along the drain bus line 56 has a linear shape. The other configurations are the same as those in the first embodiment.

In the liquid crystal display device of Comparative Example 1, as shown in FIG. 4, the disclination 23 is displaced from the boundary position 22 of the alignment processing section, and the boundary 22 of the alignment processing section is displaced.
It was confirmed that this may occur outside the light-shielding portion 26 provided so as to be aligned with. This greatly deteriorates the image quality. Further, FIG. 4 also shows the reverse tilt domain generated on the pixel electrode at this time. The reverse tilt domain is located on the first substrate 11 of the pixel electrode 71 in a position opposite to the pretilt direction of the liquid crystal molecules near the surface, that is, in Comparative Example 1, with respect to the first substrate 11 in FIG. Arrow 11 indicating the orientation direction
It occurs in the part located behind 1a and 111b.

Example 2 The structure of the liquid crystal display device of Example 2 is shown in FIG. This liquid crystal display device has the same configuration as that of the first embodiment, but uses a material having a high pretilt angle for the alignment film 31 of the first substrate 11 on which the pixel electrode 71 is provided, and is common. A material having a low pretilt angle is used for the orientation film 32 of the second substrate 12 on which the electrode 72 is provided, and the second substrate 12 is subjected to orientation treatment in a uniform direction. This is different from that shown in the first embodiment. After all, only the first substrate 11 is subjected to the alignment treatment such that the liquid crystal alignment treatment direction is different for each minute region. After the alignment film 32 is formed on the second substrate 12, a rubbing process in a certain direction is performed. Even in such a configuration, when voltage is applied, the rising directions of the liquid crystal molecules are different between the regions A and B, and the same effect as that of the first embodiment can be obtained. Note that the magnitudes of the pretilt angles on the surface of the first substrate 11 may differ corresponding to the minute regions A and B having different orientation processing directions with respect to the first substrate 11. In such a case, the rubbing direction with respect to the second substrate 12 may be set so that the pretilt directions in the vicinity of the surfaces of the two substrates do not coincide with each other in a region having a larger pretilt angle, that is, a so-called splay type orientation. , More stably divided liquid crystal alignment can be obtained.

In FIG. 5, the rubbing direction for the first substrate 11 is indicated by arrows 111a and 111b, and the rubbing direction for the second substrate 12 is indicated by arrow 112.
Indicated by. Small area A and area B with different orientations
Boundary 22 (dashed line in the figure) of each of the pixel electrodes 71 is a straight line parallel to the extending direction of the gate bus line 55 and crosses substantially the central portion of each pixel electrode 71, as in the first embodiment. It is set at a position between the gate bus line 55 and the active element 54 that drives the pixel electrode.

The liquid crystal display device of the second embodiment is also the same as the first embodiment.
Similarly, in order to prevent light leakage from the disclination portion, the light shielding portion 26 is provided on the first substrate on which the pixel electrode 71 is provided.

Also, in the liquid crystal display device of the second embodiment, as in the first embodiment, in the planar shape of each pixel electrode 71,
A notch portion 74 is provided so as to be aligned with the position of the boundary of the alignment treatment section that crosses the substantially central portion of the pixel electrode 71. The shape of the cut portion 74 is a shape that cuts out a portion where a reverse tilt domain is likely to occur on the pixel electrode, and is the same shape as that of the first embodiment. Regarding the size of the cut portion 74, as in the first embodiment, 6 μm and 12 μm and 1
It carried out about 3 types of 8 micrometers.

Also in the structure of the second embodiment, as in the case of the first embodiment, the disclination generated at the boundary of the liquid crystal alignment treatment section is fixed at a predetermined position. Therefore, it was confirmed that the disclination did not protrude into the pixel opening and a uniform and good image quality was obtained over the entire surface of the liquid crystal display device. This was confirmed in each of the above-mentioned three sizes of cuts.

<< Comparative Example 2 >> A liquid crystal display device having the same structure as that of the example 2 but the plane shape of each pixel electrode 71 different from that of the example 2 was manufactured. That is, the pixel electrode 71
Has no cut portion in its planar shape, and the portion along the drain bus line 56 has a linear shape. The other configurations are the same as those in the second embodiment.

In the liquid crystal display device of Comparative Example 2, as in the case of Comparative Example 1, the disclination 23 is provided so as to be displaced from the boundary position 22 of the alignment processing section and aligned with the boundary 22 of the alignment processing section. It was confirmed that the light might be generated by protruding from the light shielding portion 26. This greatly deteriorates the image quality.

Example 3 The structure of the liquid crystal display device of Example 3 is shown in FIG. This liquid crystal display device has the same configuration as that of the first embodiment, but the first substrate 11 and the second substrate 12 are pretilted in a direction in which liquid crystal molecules are uniform in the vicinity of the surfaces of the respective substrates. In addition, the alignment treatment is performed such that the magnitude of the pretilt angle of the liquid crystal molecules near the surface of the substrate is different depending on the minute regions A and B. It's different. Here, in the region B, near the surface of the first substrate 11 so that the pretilt angle near the surface of the second substrate 12 in the region A is larger than in the region near the surface of the first substrate 11. The orientation treatment is performed so that the pretilt angle at 1 is larger than the pretilt angle near the surface of the second substrate 12. Then, the alignment treatment direction is set so that the liquid crystal 20 has a splay alignment in each of the regions A and B. Even in such a configuration, when voltage is applied, the rising directions of the liquid crystal molecules are different between the regions A and B, and the same effect as that of the first embodiment can be obtained.

Further, for example, on the first substrate 11, the liquid crystal molecules are pretilted in a uniform direction near the surface and the pretilt angle of the liquid crystal molecules near the surface is similar to the third embodiment. Of the pre-tilt angle in the area A of the first substrate 11 and the first substrate 11 are different from each other. Even when the alignment film material characterized by a pretilt angle of an intermediate size to the size of the pretilt angle in the region B is used to perform the alignment treatment in the uniform direction, the region A, The rising direction of the liquid crystal molecules differs for each B, and the same effect as that of the first embodiment can be obtained. In this case as well, the shape of the pixel electrode (described later) similar to that of the third embodiment may be used.

In FIG. 6, the rubbing direction for the first substrate 11 is indicated by arrow 111, and the rubbing direction for the second substrate 12 is indicated by arrow 112. Further, the relative magnitudes of the pretilt directions and the pretilt angles of the liquid crystal molecules in the minute regions A and B near the surface of each substrate are indicated by arrows 111H and 111 for the first substrate 11.
The second substrate 12 is indicated by arrows 112H and 11H.
Shown in 2L. Here, the pretilt angles indicated by the arrows 111H and 112H are larger than the pretilt angles indicated by the arrows 111L and 112L. A small area A having different pretilt angles of liquid crystal molecules near the surface of each substrate
Similarly to the first embodiment, the boundary 22 between the area B and the area B (the one-dot chain line in the figure) is a straight line parallel to the extending direction of the gate bus line 55, and the position crossing the substantially central portion of each pixel electrode 71 and each pixel. It is set at a position between the electrode 71 and the gate bus line 55 to which the active element 54 for driving the pixel electrode is connected.

In order to perform the orientation processing in different directions for each minute area on the same substrate as described above, for example, FIG.
Each step shown in (e) to (e) may be sequentially performed. First, as shown in FIG. 7A, a first alignment agent layer 35 made of an inorganic material and characterized by a low pretilt angle is formed on the surfaces of the substrates 11 and 12 on which electrodes and bus lines are formed. Alignment films 31 and 32 are formed of two layers made of an organic material and having a high pretilt angle and a second alignment agent layer 36. Next, as shown in FIG. 7B, the alignment films 31 and 32 are formed.
A resist 40 is applied on top, and a resist pattern is formed by photolithography so as to correspond to either the area A or the area B in FIG. Then, in FIG.
As shown in (c), the second aligning agent layer 36 made of an organic material is partially removed according to the resist pattern to expose the first aligning agent layer 35 made of an inorganic material. Then, as shown in FIG.
Is removed. Finally, as shown in FIG. 7E, the rubbing process is performed in a fixed direction. This makes it possible to obtain the substrates 11 and 12 that have been subjected to the alignment treatment such that the magnitudes of the pretilt angles near the surfaces of the minute regions A and B are different.

The liquid crystal display device of Example 3 is also the same as Example 1.
Similarly, in order to prevent light leakage from the disclination portion, the light shielding portion 26 is provided on the first substrate on which the pixel electrode 71 is provided.

A portion where a reverse tilt domain is likely to occur on the pixel electrode in the alignment treatment direction in the liquid crystal display device of the third embodiment will be described below. In the liquid crystal display device of Example 3, the rising direction of the liquid crystal molecules near the central portions of both substrates when a voltage is applied is a minute area A.
Corresponds to the direction opposite to the pretilt direction on the surface of the first substrate 11 indicated by the arrow 121L, and in the minute region B, the first substrate 1 indicated by the arrow 121H.
1 corresponds to the direction of pretilt on the surface. Therefore, the “substantial pretilt direction” on the surface of the first substrate 11 in each minute region of the liquid crystal display device of the third embodiment is the opposite direction to the direction indicated by the arrow 121L in the region A. Therefore, it can be said that in the region B, the direction is indicated by the arrow 121H. Therefore,
Of the parts on the pixel electrode, the part where the reverse tilt domain is likely to occur is indicated by the arrow 121L in each minute region.
Is a part located in front of and behind the arrow 121H.

The liquid crystal display device of Example 3 is also the same as Example 1.
Similarly, in the planar shape of each pixel electrode 71, the notch portion 74 is provided so as to be aligned with the position of the boundary of the alignment processing section that crosses the substantially central portion of the pixel electrode 71. The shape of the cutout portion 74 is a shape that cuts out the above-mentioned portion where the reverse tilt domain is likely to occur on the pixel electrode, and is the same as that of the first embodiment. As for the size of the cut portion 74, it is 6 μm and 12 μm and 1 as in the first embodiment.
It carried out about 3 types of 8 micrometers.

Also in the structure of the third embodiment, as in the first embodiment, the disclination generated at the boundary of the liquid crystal alignment processing section is fixed at a predetermined position. Therefore, it was confirmed that the disclination did not protrude into the pixel opening and a uniform and good image quality was obtained over the entire surface of the liquid crystal display device. This was confirmed in each of the above-mentioned three sizes of cuts.

<< Comparative Example 3 >> A liquid crystal display device having the same structure as that of Example 3 but having a different planar shape of each pixel electrode 71 from that of Example 3 was manufactured. That is, the pixel electrode 71
Has no cut portion in its planar shape, and the portion along the drain bus line 56 has a linear shape. Other than that, the configuration is the same as that of the third embodiment.

In the liquid crystal display device of Comparative Example 3, as in the case of Comparative Example 1, the disclination 23 is provided so as to be displaced from the boundary position 22 of the alignment processing section and aligned with the boundary 22 of the alignment processing section. It was confirmed that the light might be generated by protruding from the light shielding portion 26. This greatly deteriorates the image quality.

Example 4 The structure of the liquid crystal display device of Example 4 is shown in FIG. 9 and 10 both show the gate bus line 5 showing the configuration of the liquid crystal display device of FIG.
10 is a cross-sectional view taken along a cross section orthogonal to the direction in which 5 extends, and FIG. 9 shows a configuration near the gate bus line, and FIG.
Shows the configuration of the cross section indicated by EE 'in FIG.
FIG. 11 shows the configuration of the cross section taken along the line FF 'in FIG. This liquid crystal display device has the same configuration as that shown in the first embodiment, but has minute regions A and B on both substrates 11 and 12.
The rubbing processing direction, the boundary position between the minute regions A and B, and the planar shape of the pixel electrode 71 are different from those in the first embodiment.

The first substrate 11 is indicated by an arrow 111 in FIG.
The second substrate 12 is oriented in the directions indicated by a and 111b in the directions indicated by arrows 112a and 112b in FIG. A boundary 22 (a dashed-dotted line in the drawing) between the region A and the region B is a straight line parallel to the extending direction of the gate bus line 55, and at a position which crosses the substantially central portion of each pixel electrode 71 and on the gate bus line 55. When the shape of the portion where the drain bus line 56 or the storage capacitor terminal 58 does not overlap is roughly regarded as a rectangle, the width of the rectangle is divided into approximately two parts. Note that in a liquid crystal display device that does not have a storage capacitor portion or a liquid crystal display device in which the storage capacitor terminals do not overlap the gate bus line,
The boundary 22 of the alignment processing section is a straight line that is parallel to the extending direction of the gate bus line 55, and passes through a position that crosses substantially the central portion of each pixel electrode 71 and a substantially central portion of the width of the gate bus line 55. It should be the position. Also in this fourth embodiment, by combining alignment film materials having different pretilt angles with each other as in the second embodiment, or by using a two-layer alignment film as in the third embodiment, the process steps are performed. It can be simplified.

The liquid crystal display device of Example 4 is also the same as Example 1.
Similarly, in order to prevent light leakage from the disclination, the same thin film layer as the conductive thin film layer forming the gate bus line 55 is formed on the first substrate on which the pixel electrode 71 is provided. The pixel electrode 71 has a light-shielding portion 26 electrically insulated from the pixel electrode 71 by an insulating layer 57 (see FIGS. 10 and 11).

The shape of the pixel electrode 71 is such that it has a notch 74 at a position aligned with the boundary of the alignment processing section that crosses the substantially central portion of the pixel electrode 71. The shape of the notch 74 is an elongated shape such that its longitudinal direction is located along the boundary of the alignment processing section set at a position crossing the pixel electrode 71, and the pixel is formed along the boundary 22 of the alignment processing section. The shape is such that the pixel electrode 71 is cut from both sides of the electrode 71. The position of the center line in the longitudinal direction of the cutout portion 74 coincides with the position of the boundary 22 of the alignment treatment section. With respect to the width of the cut portion in the direction orthogonal to the longitudinal direction, it was carried out for three types of 3 μm, 6 μm and 9 μm. Further, in order to prevent the pixel electrode 71 from being broken and causing a defect in the constricted portion of the cutout 74, the pixel electrode 71 is the same as the conductive thin film layer forming the drain bus line 56 in the constricted portion of the cutout 74. Is reinforced by the division preventing terminal 75 which is made of the thin film layer and is electrically connected to the pixel electrode 71 (see FIG. 11).

Next, the position where disclination occurs in the liquid crystal display device of the fourth embodiment will be described with reference to FIGS. 8, 9 and 10. 9 and 10 are both sectional views taken along a cross section orthogonal to the direction in which the gate bus line 55 extends. FIG. 9 shows the boundary 2 of the alignment treatment section set at a position on the gate bus line 55.
2 shows a portion including 2 and FIG. 10 shows a boundary 2 of the alignment processing section which is set at a position which crosses substantially the center of the pixel electrode 71.
A portion including 2 is shown. 9 and 10, the electric field direction is shown by a dotted line.

First, the generation position of disclination along with the boundary 22 of the alignment processing section set at the position passing on the gate bus line will be described with reference to FIG.
In this liquid crystal display device, when the shape of the portion on the gate bus line 55 where the drain bus line 56 or the storage capacitor terminal 58 does not overlap is roughly regarded as a rectangle, the width of the rectangle is divided into two substantially equal parts. Boundaries 22 of the alignment treatment section are set at the positions, and the liquid crystal molecules 21 on both sides of the alignment treatment section have ends opposite to the boundary side from the first substrate provided with the gate bus line 55. Since the alignment treatment is performed so as to rise in a direction away from the liquid crystal layer, the direction of the electric field applied to the liquid crystal layer coincides with the pretilt direction, and the disclination 23 is located at a predetermined position, that is, the boundary 22 of the liquid crystal alignment treatment section. It is fixed.

Next, the position where the disclination occurs along the boundary of the alignment processing section that crosses the substantially central portion of the pixel electrode 71 will be described with reference to FIG. In this liquid crystal display device, in the shape of the pixel electrode 71, the pixel electrode 71
Has a notch 74 at a position aligned with the boundary of the alignment processing section that crosses substantially the center of the liquid crystal molecule 21 on both sides of the boundary of this alignment processing section. Since the alignment treatment is performed so that it rises in a direction away from the first substrate provided with, the direction of the electric field applied to the liquid crystal layer matches the pretilt direction, and the disclination 23 is at a predetermined position, that is, the liquid crystal. It is fixed at the position of the boundary 22 of the orientation processing section.

As described above, the disclinations associated with the boundaries 22 of the orientation-processed sections are fixed at predetermined positions, respectively. Therefore, as shown in FIG. 8, the disclinations 23 are fixed at predetermined positions as a whole. As a result, it was confirmed that the liquid crystal display device did not protrude into the pixel opening and that a uniform and good image quality was obtained over the entire surface of the liquid crystal display device. This was confirmed in the case of each of the three width cuts described above.

<< Comparative Example 4 >> A liquid crystal display device having the same structure as that of Example 4 except that the planar shape of each pixel electrode 71 is different from that of Example 4 was manufactured. That is, the pixel electrode 71
Has no cut portion in its planar shape, and the portion along the drain bus line 56 has a linear shape. Other than that, the configuration is the same as that of the fourth embodiment.

In the liquid crystal display device of Comparative Example 4, FIG.
, The disclination 23 is displaced from the boundary position 22 of the alignment processing section,
It was confirmed that this may occur outside the light-shielding portion 26 provided in alignment with No. 2. This greatly deteriorates the image quality. Further, FIG. 12 also shows the reverse tilt domain generated on the pixel electrode at this time. The reverse tilt domain is the first part of the pixel electrode 71 in each region on both sides of the boundary of the position where the side along the drain bus line of the pixel electrode 71 intersects with the boundary 22 of the alignment processing section. An arrow 111 indicating the alignment treatment direction with respect to the first substrate 11 in FIG. 12 in a portion located near the surface of the substrate 11 in a direction different from the pretilt direction of the liquid crystal molecules, that is, in Comparative Example 4.
It occurs in a portion located in a direction different from the directions of a and 111b.

Example 5 The structure of the liquid crystal display device of Example 5 is shown in FIG. This liquid crystal display device has the same configuration as that of the fourth embodiment, but is a liquid crystal display device that is configured by a simplified process by combining different alignment film materials as shown in the second embodiment. That is, the alignment film 3 of the second substrate 12 on which the common electrode 72 is provided is formed by using a material having a high pretilt angle for the alignment film 31 of the first substrate 11 on which the pixel electrode 71 is provided.
A material having a low pretilt angle is used for 2 and the second substrate 12 is subjected to an alignment treatment in a uniform direction.

In FIG. 13, the rubbing direction for the first substrate 11 is shown by arrows 111a and 111b, and the rubbing direction for the second substrate 12 is arrow 11.
2 shows. A boundary 22 (a dot-and-dash line in the drawing) between the minute regions A and B having different orientation processing directions is similar to that in the fourth embodiment.
It was a straight line parallel to the direction in which the gate bus line 55 extends, and a position that crosses substantially the center of each pixel electrode 71 and a position that passes over the gate bus line 55.

In the liquid crystal display device shown in the fifth embodiment, the planar shape of the pixel electrode 71 is different from that shown in the fourth embodiment. That is, as shown in FIG.
The shape of the cutout 74 is a shape in which the pixel electrode 71 is cut from both sides of the pixel electrode 71 along the boundary of the alignment processing section set at a position crossing the pixel electrode 71. Of the corners, the corners where the reverse tilt domain is likely to occur are chamfered. The corner portion where the reverse tilt domain is likely to occur is the first substrate 1 in each of the minute regions A and B.
1. Arrows 111a and 111b indicating the orientation processing direction with respect to 1
Is a corner located in a direction different from the tip direction of. The chamfered shape was a slanted linear shape as shown in FIG. 13, and the chamfered sizes were two kinds of slanted sides having lengths of 3 μm and 6 μm.

In the liquid crystal display device according to the fifth embodiment, as shown in FIG. 13, the cutout portion 7 of the pixel electrode 71 is formed.
Boundary 22 of the alignment treatment section that crosses the pixel electrode in the liquid crystal display device according to the fourth embodiment among the corners of the pixel electrode associated with No. 4
Since the disclination 23 is chamfered at the corner located at the position where the disclination 23 partially deviates from the boundary of the alignment treatment section, the disc is more accurately discriminated than in the liquid crystal display device shown in the fourth embodiment. The lineation 23 was fixed to the boundary of the alignment treatment section. Therefore, it was confirmed that the disclination did not protrude into the pixel opening and a uniform and good image quality was obtained over the entire surface of the liquid crystal display device. This was confirmed in each of the cases where the chamfering of the three sizes described above was performed. In addition,
The chamfer shape can be any other shape such as an arc shape,
The same effect can be expected.

<< Embodiment 6 >> The structure is the same as that of the embodiment 5, but the shape of the notch 74 of each pixel electrode 71 is the same as that of the embodiment 5.
I made a different liquid crystal display device. As shown in FIG. 14, the shape of the notch 74 in the sixth embodiment is such that an elongated hole is formed such that its longitudinal direction is located along the boundary 22 of the alignment processing section set at the position crossing the pixel electrode 71. It has such a shape. Also, the notch 7
Corresponding to the shape of No. 4, two division prevention terminals 75 are provided for each pixel electrode. A part of the division prevention terminal 75 also serves as a light shielding portion for disclination. Other than that, the configuration is the same as that of the fifth embodiment.

Also in the structure of the sixth embodiment, as in the case of the fifth embodiment, as shown in FIG. 14, the disclination generated at the boundary of the liquid crystal alignment treatment section is fixed at a predetermined position. . Therefore, it was confirmed that the disclination did not protrude into the pixel opening and a uniform and good image quality was obtained over the entire surface of the liquid crystal display device.

<< Embodiment 7 >> A liquid crystal display device having the same structure as that of the embodiment 2 except that the planar shape of each pixel electrode 71 is different from that of the embodiment 2 was manufactured. The planar shape of the pixel electrode in Example 7 is as shown in FIG.
In one side along the drain bus line 56, the distance between the side and the drain bus line adjacent to the side is different on both sides of the boundary 22 of the alignment processing section that crosses the pixel electrode 71. In the portion of the pixel electrode located in the direction opposite to the pretilt direction of the liquid crystal molecules, the distance between the side of the pixel electrode and the drain bus line is large. The other configurations are the same as those in the second embodiment. The distance between the side of the pixel electrode 71 and the drain bus line 56 was set to 8 μm in the above-mentioned portion having a large distance, and set to 5 μm in the other portions.

In the structure of the seventh embodiment, the reverse tilt region is liable to be generated in the portion located in the direction opposite to the pretilt direction of the liquid crystal molecules on the pixel electrode.
Since the distance between the side and the drain bus line adjacent to the side is large, the direction of the lateral electric field generated at this portion is weakened. As a result, as shown in FIG. 16, the disclination generated at the boundary of the liquid crystal alignment treatment section was fixed at a predetermined position. Therefore, it was confirmed that the disclination did not protrude into the pixel opening and a uniform and good image quality was obtained over the entire surface of the liquid crystal display device.

<Embodiment 8> A liquid crystal display device having the same structure as that of Embodiment 2 but having a different planar shape of each pixel electrode 71 from that of Embodiment 2 was manufactured. As shown in FIG. 16, the planar shape of the pixel electrode in the eighth embodiment has the cutout portion 74 similar to that in the second embodiment, and further, in the side along the drain bus line 56 of the pixel electrode 71, The distance between the side and the drain bus line adjacent to the side is different on both sides of the boundary 22 of the alignment processing section that crosses the pixel electrode 71. In the part located in the direction opposite to the pretilt direction of the liquid crystal molecules on the pixel electrode,
The distance between the side of the pixel electrode and the drain bus line is large. The other configurations are the same as those in the second embodiment. As for the size of the cut portion, the length of the diagonal side shown in FIG. 16 is 8
The size was set to be μm. The distance between the side of the pixel electrode 71 and the drain bus line 56 was set to 8 μm in the above-mentioned portion having a large distance, and set to 5 μm in the other portions.

In the structure of the eighth embodiment, the reverse tilt region is likely to occur, and the liquid crystal molecules on the pixel electrode are located in the opposite direction to the pretilt direction.
Since the distance between the side and the drain bus line adjacent to the side is large, the direction of the lateral electric field generated at this portion is weakened. As a result, as shown in FIG. 16, the disclination generated at the boundary of the liquid crystal alignment treatment section was fixed at a predetermined position more stably than in the case of Example 2. Therefore, it was confirmed that the disclination did not protrude into the pixel opening and a uniform and good image quality was obtained over the entire surface of the liquid crystal display device.

<Embodiment 9> A liquid crystal display device having the same structure as that of Embodiment 5 but having a different planar shape of each pixel electrode 71 from that of Embodiment 5 was manufactured. The planar shape of the pixel electrode in Example 9 is as shown in FIG.
In one side along the drain bus line 56, the distance between the side and the drain bus line adjacent to the side is different on both sides of the boundary 22 of the alignment processing section that crosses the pixel electrode 71. In the portion of the pixel electrode located in the direction opposite to the pretilt direction of the liquid crystal molecules, the distance between the side of the pixel electrode and the drain bus line is large. Other than that, the configuration is the same as that of the fifth embodiment. The distance between the side of the pixel electrode 71 and the drain bus line 56 was set to 8 μm in the above-mentioned portion having a large distance, and set to 5 μm in the other portions.

In the structure of the ninth embodiment, in the portion located in the direction opposite to the pretilt direction of the liquid crystal molecules on the pixel electrode where the reverse tilt region is likely to occur,
Since the distance between the side and the drain bus line adjacent to the side is large, the direction of the lateral electric field generated at this portion is weakened. As a result, as shown in FIG. 17, the disclination generated at the boundary of the liquid crystal alignment treatment section was fixed at a predetermined position. Therefore, it was confirmed that the disclination did not protrude into the pixel opening and a uniform and good image quality was obtained over the entire surface of the liquid crystal display device.

<< Embodiment 10 >> The structure of the liquid crystal display device of Embodiment 10 is shown in FIG. This liquid crystal display device
The configuration is the same as that of the fifth embodiment, but the arrangement of the active elements 40 corresponding to each pixel is different from that of the fifth embodiment.
That is, in the minute region (region B) in which the active element is arranged among the minute regions in which the alignment state of the liquid crystal 20 is different, the pretilt direction of the liquid crystal molecules near the surface of the first substrate 11, that is, the alignment treatment. Directional arrow 111b
The active element 40 is arranged at a position opposite to the direction of.

The effects of the structure of this embodiment will be described below.

Also in the structure of the fifth embodiment, as shown in FIG. 19, a reverse tilt domain may occur at a position near the surface of the first substrate 11 on the side opposite to the pretilt direction. In the configuration of the tenth embodiment,
As shown in FIG. 8, the active element 40 is arranged at a position where such a reverse tilt domain is likely to occur. Therefore, in the structure of the tenth embodiment, even when such a reverse tilt domain occurs, the active element 4
It is hidden by a light-shielding film (not shown) provided on the second substrate 12 corresponding to the position of 0, and does not affect the image quality.
As a result, uniform and excellent image quality can be obtained over the entire surface of the liquid crystal display device.

<< Embodiment 11 >> The structure of the liquid crystal display device of Embodiment 11 is shown in FIG. This liquid crystal display device
The structure is similar to that shown in the fifth embodiment, but the two substrates 1
The orientation processing directions for 1 and 12 and the twisting direction of the liquid crystal 20 are different from those in the fifth embodiment. That is, the first substrate 1
1 is divided into minute areas A and B, and arrows 111a and 11
In the direction indicated by 1b, the second substrate 12 is uniformly oriented in the direction indicated by 112, and a slight amount of the right-handed chiral agent is added to the liquid crystal 20. According to the effect of the chiral agent and the above-mentioned alignment treatment direction, the liquid crystal molecules are turned clockwise at a substantially right angle from the surface of the second substrate 12 on the front side to the surface of the first substrate 11 on the back side in FIG. It is twisted and oriented. Corresponding to this, the cutout portion 74 of the pixel electrode 71 and the light shielding portion 26.
The shape of is also the left and right opposite to the configuration shown in the fifth embodiment.

That is, also in the structure of the eleventh embodiment, as shown in FIG. 20, the active element is arranged at the position where the reverse tilt domain is likely to occur. Therefore,
Even if the reverse tilt domain occurs, it is hidden by the light-shielding film provided on the second substrate corresponding to the position of the active element, so that the image quality is not affected, and as a result, it is uniform over the entire liquid crystal display device. Good image quality.

[0081]

As described above, according to the present invention,
In a liquid crystal display device in which the alignment state of the liquid crystal is different for each minute region, the cutout portion is provided in the pixel electrode in alignment with the boundary position of the alignment processing section that crosses the pixel electrode, or the side of the pixel electrode and its side. Since the gap between the gate bus line and the drain bus line along the pixel electrode is different on both sides of the boundary of the alignment processing section that crosses the pixel electrode, it affects the rising direction of liquid crystal molecules on the pixel electrode when a voltage is applied. The lateral electric field that can be exerted is weakened, or the lateral electric field is positively used to accurately fix the position of the disclination at a predetermined position, and thus a stable divided liquid crystal alignment can be obtained. it can. Therefore, the disclination does not extend into the pixel opening and deteriorates the image quality, and a uniform and good display can be obtained on the entire surface. Further, if the disclination can be fixed accurately, the area of the light-shielding portion that conceals the disclination can be reduced, so that the reduction of the pixel aperture ratio due to the light-shielding portion can be minimized, and the overall brightness is high. A liquid crystal display device having excellent viewing angle characteristics can be provided. Further, according to the present invention, the large effect as described above can be obtained only by changing the shape of the pixel electrode without adding a new process to the whole manufacturing process, and the disclination or the cut portion of the pixel electrode can be obtained. Alternatively, even in the case of forming a light-shielding portion that hides both of them and a division prevention terminal that prevents division of the pixel electrode, it is possible to form the existing conductive thin film layer, and thus it is necessary to add a new step. It is preferable in terms of cost and yield.

As described above, the effect of the present invention is extremely large.

[Brief description of drawings]

FIG. 1 is a plan view showing a configuration of a liquid crystal display device of Example 1.

FIG. 2 is a cross-sectional view illustrating a configuration near a gate bus line of the liquid crystal display device according to the first embodiment.

3 (a) to 3 (e) are diagrams each showing an alignment treatment on a substrate.

FIG. 4 is a plan view showing a configuration of a liquid crystal display device of Comparative Example 1.

FIG. 5 is a plan view showing a configuration of a liquid crystal display device of Example 2.

FIG. 6 is a plan view showing a configuration of a liquid crystal display device of Example 3.

7 (a) to 7 (e) are diagrams each showing an alignment treatment on a substrate.

FIG. 8 is a plan view showing a configuration of a liquid crystal display device of Example 4.

FIG. 9 is a cross-sectional view showing a configuration near a gate bus line of the liquid crystal display device of Example 4.

FIG. 10 is a cross-sectional view showing a configuration of a central portion of a pixel electrode of the liquid crystal display device of Example 4.

FIG. 11 is a cross-sectional view showing a configuration of a central portion of a pixel electrode of the liquid crystal display device of Example 4.

12 is a plan view showing a configuration of a liquid crystal display device of Comparative Example 4. FIG.

FIG. 13 is a plan view showing a configuration of a liquid crystal display device of Example 5.

FIG. 14 is a plan view showing a configuration of a liquid crystal display device of Example 6.

FIG. 15 is a plan view showing a configuration of a liquid crystal display device of Example 7.

16 is a plan view showing the configuration of the liquid crystal display device of Example 8. FIG.

FIG. 17 is a plan view showing the configuration of the liquid crystal display device of Example 9.

18 is a plan view showing the configuration of the liquid crystal display device of Example 10. FIG.

FIG. 19 is a plan view showing an example in which a reverse tilt domain is generated in the configuration of the fifth embodiment.

20 is a plan view showing the configuration of the liquid crystal display device of Example 11. FIG.

[Explanation of symbols]

 11 First Substrate 12 Second Substrate 20 Liquid Crystal 21 Liquid Crystal Molecule 22 Boundary of Alignment Treatment Section 23 Disclination 25 Storage Capacitance Section 26 Light-Shielding Section 31, 32 Alignment Film 35 First Alignment Agent Layer 36 Second Alignment Agent Layer 40 Resist 54 Active element 55 Gate bus line 56 Drain bus line 57 Insulating layer 58 Storage capacitor terminal 71 Pixel electrode 72 Common electrode 74 Cut part 75 Break prevention terminal 80 Rubbing roller A, B area

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeyoshi Suzuki, 5-7-1, Shiba, Minato-ku, Tokyo Inside NEC Corporation (72) Inventor, Eikoo Shibahara 5-7-1, Shiba, Minato-ku, Tokyo Inside NEC Corporation (72) Inventor Yoshihiko Hirai 5-7-1 Shiba, Minato-ku, Tokyo Inside NEC Corporation

Claims (36)

[Claims] 1. A first substrate and a second substrate provided to face each other, pixel electrodes provided in a matrix on the first substrate, and at least one pixel electrode for each pixel electrode. An active element provided on one substrate for driving a corresponding pixel electrode; a gate bus line and a drain bus line provided on the first substrate to which the active elements are respectively connected; and the second substrate A common electrode provided above, and a liquid crystal sandwiched between the first substrate and the second substrate, wherein the alignment state of the liquid crystal is different for each minute region,
In a liquid crystal display device in which at least one of the first substrate and the second substrate is subjected to an alignment treatment in a division corresponding to the minute region, at least one boundary of alignment treatment sections crosses the pixel electrode. The pixel electrode has at least one notch in its planar shape, aligned with at least one of the boundaries of the alignment processing section positioned so as to cross the pixel electrode. Liquid crystal display device. 2. The liquid crystal display device according to claim 1, wherein the liquid crystal sandwiched between the two substrates is in a twisted nematic alignment state in at least one of the minute regions having different alignment states of the liquid crystal. 3. A disk on the first substrate, the second substrate, or both substrates aligned with at least one of the boundaries of the alignment processing section set at a position across the pixel electrode. The liquid crystal display device according to claim 1 or 2, further comprising a light-shielding portion that hides the liner, the cutout portion, or both. 4. The light shielding portion is formed of the same layer as a conductive thin film layer forming the gate bus line or formed of the same layer as a conductive thin film layer forming the drain bus line. 4. The liquid crystal display device according to claim 3, wherein the liquid crystal display device is composed of either or both. 5. A disconnection prevention terminal, which is provided on the first substrate and electrically connected to the pixel electrode, is provided in the vicinity of at least one of the cutouts. The described liquid crystal display device. 6. The disconnection prevention terminal is formed of the same layer as a conductive thin film layer forming the gate bus line,
6. The liquid crystal display device according to claim 5, wherein the liquid crystal display device is formed of the same layer as the conductive thin film layer forming the drain bus line, or both. 7. The liquid crystal display device according to claim 5, wherein at least a part of the division preventing terminal also serves as at least a part of the light shielding part. 8. A liquid crystal molecule in the vicinity of the central portion between both substrates in each of the minute regions on both sides of at least one of the boundaries of the alignment processing section positioned so as to cross the pixel electrode, when a voltage is applied. 8. The liquid crystal display device according to claim 1, wherein the alignment treatment is performed so that one of both ends of the liquid crystal molecule, which is farther from the boundary, rises in a direction away from the first substrate. . 9. The shape of at least one of the cutouts is such that, in at least one region of the minute region, a boundary of the alignment treatment section of a portion of the pixel electrode crosses a side of the pixel electrode. 9. The liquid crystal display device according to claim 8, which has a shape in which a portion in the vicinity of the position where the liquid crystal molecules are located and in the vicinity of the surface of the first substrate is located in the longitudinal direction. 10. A liquid crystal molecule in the vicinity of the central portion between both substrates in each of the minute regions on both sides of at least one of the boundaries of the alignment processing section positioned so as to cross the pixel electrode, when a voltage is applied. 8. The liquid crystal display device according to claim 1, wherein the alignment treatment is performed so that one of both ends of the liquid crystal molecule, which is closer to the boundary, rises in a direction away from the first substrate. . 11. The shape of at least one of the notches is an elongated shape such that the longitudinal direction of the notch is located along the boundary of the orientation-treated section.
The described liquid crystal display device. 12. The liquid crystal display device according to claim 11, wherein in at least one of the elongated notches, the position of the center line in the longitudinal direction of the notches substantially coincides with the boundary position of the alignment processing section. 13. The liquid crystal display device according to claim 11, wherein at least one shape of the elongated cutouts is a shape in which an elongated hole is formed in the pixel electrode. 14. The shape of at least one of the elongated notches is a shape of notching the pixel electrode along both sides of the pixel electrode along the boundary of the alignment processing section. 12. The liquid crystal display device according to item 12. 15. At least one of the corners of the pixel electrode attached to the notch having a shape that cuts the pixel electrode from both sides or one side of the pixel electrode along the boundary of the alignment treatment section, among the notches. 15. The liquid crystal display device according to claim 14, wherein the liquid crystal display device is chamfered. 16. In at least one of the minute regions, a corner portion of a pixel electrode attached to the cut portion is located in a direction different from a longitudinal direction of liquid crystal molecules on the surface of the first substrate. The liquid crystal display device according to claim 15, wherein the corner portion is chamfered. 17. At least one of the boundaries of the alignment processing section is set along the extending direction of the gate bus line and at least a part of the boundary is located between the gate bus line and the pixel electrode. In each of the minute regions on both sides of the boundary, the liquid crystal molecules near the central portion between the substrates have the first end of the both ends of the liquid crystal molecule near the boundary when a voltage is applied. 17. The liquid crystal display device according to claim 1, wherein the alignment treatment is performed so as to stand in a direction away from the substrate. 18. The pixel electrode, or for each of the pixel electrodes, a storage capacitor terminal connected to the pixel electrode provided on the first substrate, and / or both of them are active to drive the pixel electrode. A gate bus line different from the gate bus line connected to the element forms an accumulating portion having an overlapping portion via an insulating layer, and at least along the extending direction of the gate bus line and At least one of the boundaries of the alignment processing section, which is set to be located between the gate bus line and the pixel electrode, is connected to the pixel electrode and an active element driving the pixel electrode. The liquid crystal display device according to claim 17, wherein the liquid crystal display device is provided between the gate bus line and the gate bus line. 19. At least one of the boundaries of the alignment processing section is set so as to be along the extending direction of the gate bus line and at least a part of the boundary is located on the gate bus line. In each of the minute regions on both sides, liquid crystal molecules in the vicinity of the central portion between the two substrates are arranged such that, when a voltage is applied, one of both end portions of the liquid crystal molecule, which is farther from the boundary, is separated from the first substrate. The alignment treatment is performed so as to stand up.
6. The liquid crystal display device according to item 6. 20. A boundary of the alignment processing section, which is set along the extending direction of the gate bus line and at least a part of which is located on the gate bus line, is a gate of the gate bus line. 20. The liquid crystal display device according to claim 19, wherein the liquid crystal display device has a width in a direction orthogonal to the extending direction of the bus line and passes through substantially the central portion. 21. An active element for driving the pixel electrode, wherein the pixel electrode, or each of the pixel electrodes is provided on the first substrate and a storage capacitor terminal connected to the pixel electrode, or both of them. A gate bus line different from the gate bus line connected to the element forms an accumulating portion having an overlapping portion via an insulating layer, and at least along the extending direction of the gate bus line and A part of the boundary of the alignment treatment section, which is set so as to be partly located on the gate bus line, on the gate bus line where another wiring or electrode such as a drain bus line or a storage capacitor terminal does not overlap 20. The position is set so as to roughly divide the width of the rectangle when the shape is roughly regarded as a rectangle.
The described liquid crystal display device. 22. Of each side of the pixel electrode, at least one of the sides of the alignment processing section crosses and at least one side of the sides along the extending direction of the gate bus line or the drain bus line. 3. The shape of claim 1 is a modified shape such that the distance between the side and the gate bus line or the drain bus line along the side is different on both sides of the boundary of the alignment treatment section. 21. The liquid crystal display device according to item 21. 23. In each of the minute regions, among the both ends of the liquid crystal molecules near the surface of the first substrate, the alignment of the liquid crystal molecules is performed from near the central portion between the two substrates toward the surface of the first substrate. When the direction is traced, the direction of the end of the liquid crystal molecules near the center between both substrates, which corresponds to the end that rises away from the first substrate when a voltage is applied, is located near the surface of the first substrate. Defined as a substantial pretilt direction in the above, at least one shape of the deformed sides is a substantial pretilt direction in the vicinity of the surface of the first substrate among the side portions having the deformed shape. 23. The liquid crystal display according to claim 22, which has a shape in which a distance between the side and a gate bus line or a drain bus line along the side is larger in a portion located in a direction opposite to that in the other portion than in other portions. Dress Place. 24. A first substrate and a second substrate which are provided to face each other.
A substrate, pixel electrodes provided in a matrix on the first substrate, and at least one active element provided on the first substrate for driving the corresponding pixel electrode for each pixel electrode, A gate bus line and a drain bus line provided on the first substrate and connected to the respective active elements, a common electrode provided on the second substrate, the first substrate and the second substrate A liquid crystal sandwiched between the substrates of, so that the alignment state of the liquid crystal is different for each minute region,
In a liquid crystal display device in which at least one of the first substrate and the second substrate is subjected to an alignment treatment in a division corresponding to the minute region, at least one boundary of alignment treatment sections crosses the pixel electrode. At least one of the sides of the pixel electrode that crosses at least one of the boundaries of the alignment processing section and is along the direction in which the gate bus line or the drain bus line extends. 2. The liquid crystal display device according to claim 1, wherein the shape is a modified shape such that the distance between the side and the gate bus line or the drain bus line along the side is different on both sides of the boundary of the alignment treatment section. 25. The liquid crystal display device according to claim 24, wherein the liquid crystal sandwiched between the substrates is in a twisted nematic type alignment state in at least one of the minute regions having different alignment states of the liquid crystal. 26. In each of the minute regions, among the both ends of the liquid crystal molecule in the vicinity of the surface of the first substrate, the alignment of the liquid crystal molecule from the vicinity of the central portion between the substrates toward the surface of the first substrate. When the direction is traced, the direction of the end of the both ends of the liquid crystal molecule near the center between both substrates, which corresponds to the end that rises away from the first substrate when voltage is applied, is near the surface of the first substrate. Defined as a substantial pretilt direction in the above, at least one shape of the deformed sides is a substantial pretilt direction in the vicinity of the surface of the first substrate among the side portions having the deformed shape. 25. The shape in which the distance between the side and the gate bus line or the drain bus line along the side is larger in the portion located in the direction opposite to that in the other portion than in the other portions. 5. The liquid crystal display device according to item 5. 27. Aligning with at least one of the boundaries of the alignment processing section set at a position across the pixel electrode,
27. The liquid crystal display device according to claim 24 or 26, wherein a light-shielding portion for concealing disclination is provided on the first substrate, the second substrate, or both substrates. 28. The light shielding portion is formed of the same layer as a conductive thin film layer forming the gate bus line or formed of the same layer as a conductive thin film layer forming the drain bus line. 28. The liquid crystal display device according to claim 27, wherein the liquid crystal display device comprises one or both. 29. At least one of the boundaries of the alignment processing section positioned so as to cross the pixel electrode is in each minute region on both sides of the boundary, liquid crystal molecules in the vicinity of the central portion between both substrates are applied with a voltage. 29. The liquid crystal display device according to claim 24, wherein the alignment treatment is performed so that one of both ends of the liquid crystal molecule, which is farther from the boundary, rises in a direction away from the first substrate. . 30. In each of the minute regions on both sides of at least one of the boundaries of the alignment processing section positioned so as to cross the pixel electrode, liquid crystal molecules near the central portion between both substrates are subjected to voltage application. 29. The liquid crystal display device according to claim 24, wherein the alignment treatment is performed such that one of both ends of the liquid crystal molecule, which is closer to the boundary, rises in a direction away from the first substrate. . 31. At least one of the boundaries of the alignment processing section is set along the extending direction of the gate bus line and at least a part of the boundary is located between the gate bus line and the pixel electrode. In each of the minute regions on both sides of the boundary, the liquid crystal molecules near the central portion between the substrates have the first end of the both ends of the liquid crystal molecule near the boundary when a voltage is applied. 31. The liquid crystal display device according to claim 24, wherein the alignment treatment is performed so as to rise in a direction away from the substrate. 32. The pixel electrode, or for each of the pixel electrodes, a storage capacitor terminal connected to the pixel electrode provided on the first substrate and / or both of them are active to drive the pixel electrode. A gate bus line different from the gate bus line connected to the element forms an accumulating portion having an overlapping portion via an insulating layer, and at least along the extending direction of the gate bus line and At least one of the boundaries of the alignment processing section, which is set to be located between the gate bus line and the pixel electrode, is connected to the pixel electrode and an active element driving the pixel electrode. 32. The liquid crystal display device according to claim 31, wherein the liquid crystal display device is provided between the gate bus line and the gate bus line. 33. At least one of the boundaries of the alignment treatment section is set so as to extend along the direction in which the gate bus line extends and at least a part thereof is located on the gate bus line. In each of the minute regions on both sides, liquid crystal molecules in the vicinity of the central portion between the two substrates are arranged such that, when a voltage is applied, one of both ends of the liquid crystal molecule, which is farther from the boundary, is separated from the first substrate. 31. The liquid crystal display device according to claim 24, wherein the alignment treatment is performed so as to stand up. 34. A boundary of the alignment processing section, which is set along the extending direction of the gate bus line and at least a part of which is located on the gate bus line, is a gate of the gate bus line. 34. The liquid crystal display device according to claim 33, wherein the liquid crystal display device has a width in a direction orthogonal to the extending direction of the bus line and passes through a substantially central portion. 35. The pixel electrode, or for each of the pixel electrodes, a storage capacitor terminal connected to the pixel electrode and provided on the first substrate, or both of them, are active to drive the pixel electrode. A gate bus line different from the gate bus line connected to the element forms an accumulating portion having an overlapping portion via an insulating layer, and at least along the extending direction of the gate bus line and A part of the boundary of the alignment treatment section, which is set so as to be partly located on the gate bus line, on the gate bus line where another wiring or electrode such as a drain bus line or a storage capacitor terminal does not overlap. 33. The position is set so as to roughly divide the width of the rectangle when the shape of the rectangle is roughly regarded as a rectangle.
The described liquid crystal display device. 36. In each of the minute regions, of the both ends of the liquid crystal molecules near the surface of the first substrate, the alignment of the liquid crystal molecules from the vicinity of the central portion between the substrates toward the surface of the first substrate. When the direction is traced, the direction of the end of the both ends of the liquid crystal molecule near the center between both substrates, which corresponds to the end that rises away from the first substrate when voltage is applied, is near the surface of the first substrate. In the substantial pretilt direction in, the at least one of the minute regions in which the active element is arranged has a side opposite to the direction of the substantial pretilt in the minute regions. 36. The liquid crystal display device according to claim 1, wherein the active element is arranged at the position.