JP2713210B2 - Liquid crystal display - Google Patents

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 area.

[0002]

2. Description of the Related Art A liquid crystal display (LCD) generally has a structure in which liquid crystal is inserted between a pair of opposed substrates. In a twisted nematic liquid crystal display device,
Two substrates each having an alignment film provided thereon are used, and a polarizing plate is disposed outside each of the substrates. The liquid crystal molecules are helically aligned so that the longitudinal direction is substantially parallel to the two substrates and twisted from one substrate to the other substrate. The orientation directions of the molecules are substantially 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 inclined from parallel to the substrate.
The alignment direction and pretilt direction of the liquid crystal molecules near each substrate surface 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 the liquid crystal molecules near each substrate surface can also be controlled by forming an alignment film by oblique evaporation. Here, the pretilt direction refers to the direction of the end rising from the substrate in the direction of both ends of the liquid crystal molecules.

In such a twisted nematic liquid crystal display device, when a voltage is applied to the liquid crystal layer, the liquid crystal molecules that have been twisted and aligned rise in the direction perpendicular to the substrate. Then, the transmittance of the incident light can be changed by the change of the alignment state. The angle at which the liquid crystal molecules rise varies depending on the magnitude of the applied voltage. By controlling the magnitude of this voltage, gradation display from a bright state to a dark state can be performed. In recent years, a liquid crystal display device of a type in which pixels are arranged in a matrix of length and width and each pixel is driven by an active element (a so-called active matrix type liquid crystal display device: AM-LCD) has been widely and widely used. In an active matrix type liquid crystal display device, active elements are provided near intersections of a plurality of gate bus lines and drain bus lines running vertically and horizontally, and transparent pixels provided in an area surrounded by these bus lines are provided. A desired voltage can be applied to the electrode to maintain the voltage. In an active matrix type liquid crystal display device, a storage capacitor is often connected in parallel with a pixel capacitor in order to more efficiently hold a 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 driving the pixel so as to project through the insulating layer. This is an effective means because the layer structure of the electrode can be simplified, the process can be simplified, and a storage capacitor can be provided without lowering the pixel aperture ratio.

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

[0005] Such a change in gradation characteristics due to visual perception is as follows.
This is due to the asymmetry of the alignment state of the liquid crystal molecules. The direction in which the liquid crystal molecules rise when a voltage is applied to the liquid crystal layer is determined by the direction of the pretilt 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 rise according to the pretilt direction, that is, the direction of the liquid crystal alignment processing. Further, since the rising angle of the liquid crystal molecules changes depending on the applied voltage, the above-described gradation display 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 surfaces of both substrates and large near the center between both substrates. Therefore, the rising angle of the liquid crystal molecules existing near the center between the substrates with respect to the substrates mainly contributes to the display brightness. In the state where the liquid crystal molecules near the center between the two substrates rise at an angle to the substrate surface, that is, in the halftone display state, when the liquid crystal display device is observed from the direction in which the liquid crystal molecules rise, the screen is displayed. Looks whitish and looks black when viewed from the opposite direction.

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

In the case where a plurality of minute regions having different rising directions of liquid crystal molecules are provided, an alignment defect called disclination occurs at a boundary between the regions having different rising directions of liquid crystal molecules, and contrast is increased. This causes problems such as a decrease in the temperature. In order to prevent the image quality from deteriorating 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 at which disclination occurs is accurately controlled. However, the rising direction of the liquid crystal molecules is affected by the regulating 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 gate bus line and the drain bus line, the pixel electrode and In addition, it is not easy to accurately control the direction in which the liquid crystal molecules rise, and hence the position at which disclination occurs, because of the influence of the lateral electric field between them. As the resolution of the liquid crystal display device becomes higher and the distance between the pixel electrode and the gate bus line and the drain bus line becomes smaller, the horizontal electric field generated between the pixel electrode and the gate bus line and the drain bus line also becomes larger and becomes stable. It is much more difficult to achieve a split orientation. In such a case, the disclination is shifted from the original boundary position of the alignment processing section or gradually moves to another position after the occurrence, so that the disclination is provided in alignment with the boundary position of the alignment processing section. Protruding from the light blocking part,
Image quality is degraded.

When the disclination occurs at a position deviating from the boundary position of the alignment processing section, a reverse tilt domain, that is, a domain in which liquid crystal molecules rise 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 deviate from a predetermined position, thereby deteriorating the image quality. Of the regions on the pixel electrode, those regions where such a reverse tilt domain is likely to occur are located in the vicinity of each side or each corner of the pixel electrode or on the pixel electrode for each minute region where the alignment state of liquid crystal molecules is different. In the direction different from the “substantial pre-tilt direction” on the surface of the substrate on which the pixel electrode, the gate bus line or the drain bus line is provided. It is a part located. This is because the “substantial pretilt direction” does not coincide with the direction of the lateral electric field in this portion. Here, the “substantial pretilt direction” on the surface of the substrate refers to the orientation direction of the liquid crystal molecules from the vicinity of the center between the two substrates to the surface of the substrate, from both ends of the liquid crystal molecules near the surface of the substrate. Of the liquid crystal molecules in the vicinity of the center between the two substrates when the voltage is applied, the direction corresponding to the end that rises away from the substrate when the voltage is applied. The “substantial pretilt direction” on the substrate surface generally matches the pretilt direction on the substrate surface, but may not match in the case of so-called splay-type liquid crystal alignment in which the pretilt directions do not match between the two substrates.

In order to obtain good alignment at the boundary between the alignment treatment sections, Japanese Patent Application Laid-Open No. 5-173142 discloses that the portion of the alignment film corresponding to the boundary between the alignment treatment sections 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 processing section are arranged so as to pretilt toward the gate bus line near the substrate provided with the gate bus line, and A configuration is disclosed in which each of the divided pixel electrodes is divided through a minute gap, and the boundary between the alignment processing sections matches the 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 is pretilted toward the gate bus line. In the configuration described above, the horizontal electric field around the gate bus line acts to assist the predetermined alignment. In the configuration characterized by the divided pixel electrodes, the horizontal electric field between the divided pixel electrodes is It works to help.

However, among the structures disclosed in Japanese Patent Application Laid-Open No. 5-173142, the structure characterized by the deformed shape of the two substrates has unevenness large enough to assist predetermined liquid crystal alignment. A new process must be added in order to form the film on the surface, which leads to an increase in cost, which is not preferable. It is possible to use an existing gate bus line or drain bus line to form the unevenness, but this method cannot be applied to, for example, the boundary of the alignment processing section set on the pixel electrode. In addition, in the case where the concave portion or the convex portion is provided, the rubbing process may not be performed well in a portion that becomes a shadow of the concave portion or the convex portion when the rubbing process is performed, and the orientation may be unstable.

In the configuration disclosed in Japanese Patent Application Laid-Open No. 5-173142, which is characterized by pretilt toward the gate bus line, for example, the boundary of the alignment processing section set on the pixel electrode is also considered. Cannot stabilize the liquid crystal alignment in the vicinity of. Further, when the definition of the liquid crystal display device is further improved and the liquid crystal molecules on the pixel electrode are more susceptible to the influence of the lateral electric field around the gate bus line, the alignment may be disturbed. This is because, just above the gate bus line, an electric field is applied in the horizontal direction in a direction that causes the liquid crystal molecules to rise toward the outside of the gate bus line, so that the liquid crystal alignment immediately above the gate bus line is disturbed. This is because the liquid crystal molecules on the pixel electrode may be affected.

In the configuration disclosed in Japanese Patent Application Laid-Open No. 5-173142, which is characterized by divided pixel electrodes, it is necessary to provide a driving means comprising an active element such as a thin film transistor in accordance with each of the divided pixel electrodes. This can cause not only a decrease in pixel aperture ratio but also a decrease in yield.

[0013]

As described above, in a liquid crystal display device in which the alignment process is performed in each of the minute regions for the purpose of enlarging the viewing angle, the liquid crystal alignment is stable in each of the divided regions. This causes disclination to be shifted from the boundary position of the original alignment processing section or to be gradually moved to another position after occurrence, resulting in a decrease in contrast ratio or uneven display over the entire surface. Or display burn-in or an afterimage.

An object of the present invention is to provide a liquid crystal display device in which the alignment state of the liquid crystal is different for each of the minute regions, whereby the liquid crystal alignment is stabilized in each of the divided regions, whereby the disclination is prevented from the boundary of the alignment processing section. It is an object of the present invention to provide a liquid crystal display device which is accurately fixed at a predetermined position without displacement, and can provide a uniform and excellent display over the entire surface. Needless to say, it is not preferable that other problems such as a complicated process, a decrease in the pixel aperture ratio, or a decrease in yield are accompanied in order to realize this.

[0015]

A liquid crystal display device according to the present invention comprises a first substrate and a second substrate provided opposite to 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 the corresponding pixel electrodes, and active elements provided on the first substrate Have a gate bus line and a drain bus line respectively connected thereto, 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 the first substrate and the second substrate is subjected to an alignment process in a manner corresponding to the minute region so that the alignment state differs for each minute region, the pixel substrate traverses the pixel electrode. In the position, at least one of the boundaries of the alignment processing section is set, and in the planar shape of the pixel electrode, has a cutout in alignment with the boundary of the alignment processing section across the pixel electrode;
Alternatively, the distance between 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 processing section crossing the pixel electrode, or both are characterized.

In the present invention, disclination can be concealed by providing a light-shielding portion in alignment with the boundary position of the alignment processing section crossing the pixel electrode. In the case where a cut portion is provided in the pixel electrode, a break prevention terminal can be provided in order to prevent the pixel electrode from being broken at that portion. These light-shielding portions or division prevention terminals may be formed of the same layer as the thin film layer forming the gate bus line or the drain bus line.

Further, in the present invention, the alignment process is performed so that the liquid crystal molecules rise in the direction away from the first substrate on both sides of the boundary of the alignment process section across the pixel electrode when a voltage is applied. It can be carried out. In this case, the shape of the cut portion of the pixel electrode is changed to a portion of the portion on the pixel electrode near a position where the boundary crosses the side of the pixel electrode and a portion of the liquid crystal molecules near the first substrate. If the portion located in the longitudinal direction is cut off, 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 across the pixel electrode, the end opposite to this boundary when applying a voltage,
Orientation treatment can be performed so that 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 in which an elongated hole is formed in the pixel electrode, or may have a shape in which the pixel electrode is cut from one side or both sides along the boundary. In the case where the pixel electrode is cut from one side or both sides, by chamfering the corner of the pixel electrode attached to the cut portion, the disclination can be fixed at an extremely accurate position.

Further, a boundary of the alignment processing section is set between the pixel electrodes, and the liquid crystal molecules are arranged on both sides of the boundary in such a direction that the end on the boundary side is separated from the first substrate when a voltage is applied. An orientation treatment can be performed so as to stand up. 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 the alignment processing section is set between the pixel electrode and the liquid crystal molecules on both sides of the boundary in such a direction that an end opposite to the boundary when the voltage is applied is separated from the first substrate. An orientation treatment can be performed so as to stand up. In this case, the boundary of the alignment processing section may be set on the gate bus line.

In the case where the distance between the side of the pixel electrode and the gate bus line or drain bus line along the side is different on both sides of the boundary of the alignment section across the pixel electrode, the surface of the first substrate In a portion of the liquid crystal molecules in the vicinity that is located in a direction opposite to the “substantial pretilt direction”, the distance between the side of the pixel electrode and the gate bus line or the drain bus line along the side is other than that. What is necessary is just to make it larger.

[0020]

In the liquid crystal display device according to the present invention, the notch is provided in the pixel electrode so as to match the boundary position of the alignment processing section crossing the pixel electrode, or the side of the pixel electrode and the gate bus along the side are provided. 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, the lateral electric field that can affect the direction in which the liquid crystal molecules rise on the pixel electrode when voltage is applied Or the lateral electric field is positively utilized, so that the position of the disclination can be accurately fixed at a predetermined position. Therefore, it is possible to obtain a uniform and excellent display over the entire surface without disclination protruding into the pixel opening and deteriorating the image quality. Further, according to the present invention, the above-described great effect can be obtained only by changing the shape of the pixel electrode without adding a new step to all the manufacturing steps.

[0021]

Next, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1 FIG. 1 is a plan view showing a configuration of a liquid crystal display device of Embodiment 1, and FIG. 2 is a cross-sectional view showing a configuration near a gate bus line in the liquid crystal display device of FIG. . This liquid crystal display device has a structure in which a first substrate 11 and a second substrate 12 are overlapped so as to keep a constant interval, and a liquid crystal 20 is injected between the two substrates 11 and 12. I have. Polarizing plates (not shown) are arranged outside the substrates 11 and 12 respectively. FIG. 1 illustrates that the first substrate 11 is disposed on the back side and the second substrate 12 is disposed 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 formed in a lattice. 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 formed of a transparent conductive thin film layer made of a material such as indium tin oxide (ITO). The conductive thin film layer forming the gate bus line 55 is insulated from the conductive thin film layer forming the drain bus line 56 and the transparent conductive thin film layer forming the pixel electrode 71 by the insulating layer 57. Each of the pixel electrodes 71 corresponds to one pixel. Further, an 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 (a-Si) or polycrystalline silicon (p-Si). TFT). The gate terminal of the active element 54 is the gate bus line 5
5 and the drain terminal is a 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 is connected to the gate bus line 55 to which the active element 54 for driving the adjacent pixel electrode 71 is connected.
It overlaps so as to protrude through the insulating layer 57 (see FIG. 2), thereby forming the storage capacitor portion 25. On the first substrate 11, an alignment film 31 is formed on the outermost surface on the side in contact with the liquid crystal 20.

On the other hand, the second substrate 12 has a common electrode 72
And the alignment film 32 are stacked in this order, and the alignment film 32
Is in contact with the liquid crystal 20. The common electrode 72 is formed of a transparent conductive thin film layer made of a material such as indium tin oxide (ITO). Further, a color filter (not shown) made of R, G, and B is provided on the second substrate 12 according to each pixel electrode 71. Therefore, the liquid crystal display device according to 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 pitch at which the pixel electrodes 71 are arranged in a matrix is 67 μm in the direction in which the gate bus line 55 extends, and 201 μm in the direction in which the drain bus line 56 extends. The first substrate 11 and the second substrate 12 are superimposed on 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 and 12 are oriented in different directions for each of the band-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 arrows 112a and 112b. The boundary 22 between the region A and the region B (indicated by a dashed line) is a straight line parallel to the direction in which the gate bus line 55 extends, and crosses a substantially central portion of each pixel electrode 71, and the position of each pixel electrode 71 and its pixel It is set at a position between the active element 54 for driving the electrode and the gate bus line 55 to which the active element 54 is connected.

In order to perform the orientation treatment in different directions for each minute area on the same substrate as described above, FIGS.
The steps shown in (e) may be performed sequentially. First, FIG.
As shown in (a), alignment films 31 and 32 made of an alignment agent such as polyimide are formed on the surfaces of 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 certain direction. The rubbing process is performed by rotating a rubbing roller 80 around which a puff cloth such as rayon is wound 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 so as to correspond to either the region A or the region B in FIG. Form. Then, as shown in FIG.
The rubbing process is performed in a direction opposite to the direction shown in FIG. Finally, as shown in FIG. 3E, the resist 40 is removed using an organic solvent. Thereby, the substrates 11, 1 which are oriented in different directions for each of the minute regions A, B
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, a normal positive resist was used as the resist, and acetone was used to remove the resist.

In the first embodiment, the liquid crystal 20 includes:
E. FIG. ZLI-4 from Merck, Darmetadt
792 was used. A small amount of a left-handed chiral agent is added to this liquid crystal material. In FIG. 1, the liquid crystal molecules extend from the surface of the second substrate 12 on the near side to the first substrate 11 on the far side in accordance with the effect of the chiral agent and the above-described alignment processing direction.
The surface is twisted counterclockwise at an almost right angle toward the surface. Further, the liquid crystal molecules near the surfaces of the substrates 11 and 12 are pretilted in the direction of the tip of the arrow indicating the alignment processing direction in FIG. 1 according to the alignment processing direction described above. That is, pretilt is performed in different directions for each of the regions A and B in FIG. Therefore, when voltage is applied, the rising direction of the liquid crystal molecules differs for each of the regions A and B.

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

The liquid crystal display device of the first embodiment has a cutout 74 in the planar shape of each pixel electrode 71. The notch 74 is formed at the boundary 22 of the alignment processing section.
Among them, they are provided in alignment with the positions of the boundaries of the alignment processing sections that cross the substantially central portion of the pixel electrode 71. Further, the shape of the cutout portion 74 is different in each of the regions A and B.
A portion where a reverse tilt domain is likely to occur among the portions on the pixel electrode is cut out. More specifically, a portion of the pixel electrode 71 near the surface of the first substrate 11 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 arrows 111 a and 111 b indicating the processing direction is a right angle 2 having a straight line substantially orthogonal to the arrows indicating the alignment processing direction as the hypotenuse.
This is a shape that is cut into an equilateral triangle. Notch 74
The length of the hypotenuse of the cut portion of the right-angled isosceles triangle is 3 μm of 6 μm, 12 μm and 18 μm.
Performed on seeds.

Next, the position at which disclination occurs in the liquid crystal display device of the first embodiment will be described with reference to FIGS.

First, the position at which disclination occurs at the boundary of the alignment processing section that crosses substantially the center 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 edge of the pixel electrode 71 and the boundary 22 of the alignment processing section. In addition, since a portion of the surface of the first substrate 11 that is 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 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 processing section set between
The position where disclination occurs will be described with reference to FIG. FIG. 2 is a cross-sectional view taken along a cross section orthogonal to the direction in which the gate bus line 55 extends, and shows 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 direction of the electric field 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 on both sides of this alignment processing section, the liquid crystal molecules 21 are connected to the gate end by the edge. Since the alignment processing is performed so that the liquid crystal layer rises 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 matches the pretilt direction, and the disclination 23 is positioned at 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 alignment processing sections are fixed at predetermined positions, respectively, so that the disclinations 23 are fixed at predetermined positions as a whole as shown in FIG. As a result, it was confirmed that uniform and good image quality was obtained over the entire surface of the liquid crystal display device without protruding into the pixel opening. This was confirmed in each of the three sizes of cuts described above.

Comparative Example 1 A liquid crystal display device having the same configuration as that of the first embodiment, except that the planar shape of each pixel electrode 71 is different from that of the first embodiment was manufactured. That is, the pixel electrode 71
Has no cutout in its planar shape, and the portion along the drain bus line 56 is linear. Otherwise, the configuration is the same as that of 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 between the alignment processing sections and the boundary 22 between the alignment processing sections.
It has been confirmed that the light may protrude from the light shielding portion 26 provided in conformity with the above. This greatly degrades the image quality. FIG. 4 also shows a 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 at a position near the surface of the pixel electrode 71 in the direction opposite to the pretilt direction of the liquid crystal molecules, that is, in the comparative example 1, the reverse tilt domain corresponds to the first substrate 11 in FIG. Arrow 11 indicating orientation direction
It occurs in a portion located behind 1a and 111b.

Embodiment 2 FIG. 5 shows a configuration of a liquid crystal display device of Embodiment 2. This liquid crystal display device has the same configuration as that shown in the first embodiment, except that a material having a high pretilt angle is used 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 the alignment film 32 of the second substrate 12 on which the electrode 72 is provided, and the second substrate 12 is subjected to an alignment process in a uniform direction. This is different from the first embodiment. As a result, only the first substrate 11 is subjected to the alignment processing in which the liquid crystal alignment processing direction is different for each minute region. After forming the alignment film 32 on the second substrate 12, a rubbing process is performed in a certain direction. Also in such a configuration, when a voltage is applied, the rising direction of the liquid crystal molecules differs for each of the regions A and B, and the same effect as in the first embodiment can be obtained. In some cases, the magnitude of the pretilt angle on the surface of the first substrate 11 differs depending on the minute regions A and B in which the alignment processing directions with respect to the first substrate 11 are different. In such a case, in the region where the pretilt angle is larger, the rubbing direction with respect to the second substrate 12 may be set so that the pretilt directions near the surfaces of both substrates do not coincide with each other, that is, so-called splay-type orientation. Thus, the divided liquid crystal alignment can be obtained more stably.

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 Minute area A and area B with different orientation directions
Is a straight line parallel to the direction in which the gate bus line 55 extends, and crosses a substantially central portion of each pixel electrode 71, as in the first embodiment. It is set at a position between the gate bus line 55 to which the active element 54 for driving the pixel electrode is connected.

The liquid crystal display device of the second embodiment is also the same as that of the first embodiment.
Similarly to the above, in order to prevent light leakage from the disclination part, the light shielding part 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, similarly to the first embodiment, in the planar shape of each pixel electrode 71,
A cutout 74 is provided in alignment with the position of the boundary of the alignment processing section that crosses substantially the center of the pixel electrode 71. The shape of the cutout portion 74 is a shape for cutting out a portion where a reverse tilt domain is likely to be generated on the pixel electrode, and is the same shape as that of the first embodiment. As with the first embodiment, the size of the cut portion 74 is 6 μm, 12 μm, and 1 μm.
The test was performed for three types of 8 μm.

In the configuration of the second embodiment, as in the first embodiment, the disclination occurring at the boundary between the liquid crystal alignment processing sections is fixed at a predetermined position. Therefore, it was confirmed that the disclination did not protrude into the pixel opening and uniform and good image quality was obtained over the entire surface of the liquid crystal display device. This was confirmed in each of the three sizes of cuts described above.

Comparative Example 2 A liquid crystal display device having the same configuration as that of the second embodiment, except that the planar shape of each pixel electrode 71 is different from that of the second embodiment was manufactured. That is, the pixel electrode 71
Has no cutout in its planar shape, and the portion along the drain bus line 56 is linear. Otherwise, the configuration is the same as that of the second embodiment.

In the liquid crystal display device of Comparative Example 2, as in Comparative Example 1, the disclination 23 is provided so as to be shifted from the boundary position 22 of the alignment processing section and aligned with the boundary 22 of the alignment processing section. It has been confirmed that the light may protrude from the light-shielding portion 26 that has been generated. This greatly degrades the image quality.

Embodiment 3 FIG. 6 shows the configuration of a liquid crystal display device of Embodiment 3. This liquid crystal display device has the same configuration as that shown in Embodiment 1, except that the first substrate 11 and the second substrate 12 have pretilt liquid crystal molecules in a uniform direction near the surface of each substrate. And that the orientation process is performed so 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. Are different. Here, in the region A, the pretilt angle near the surface of the second substrate 12 is larger than the pretilt angle near the surface of the first substrate 11, and in the region B, the pretilt angle near the surface of the first substrate 11 is large. The pre-tilt angle at each of the substrates is oriented so as to be larger than the pre-tilt angle near the surface of the second substrate 12. The alignment direction is set so that the liquid crystal 20 has a splay type alignment in each of the regions A and B. Also in such a configuration, when a voltage is applied, the rising direction of the liquid crystal molecules differs for each of the regions A and B, and the same effect as in the first embodiment can be obtained.

Further, for example, similarly to the third embodiment, the first substrate 11 is provided so that 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. Of the pretilt angle in the region A of the first substrate 11 and the size of the first substrate 11 Even when an alignment treatment in a uniform direction is performed using an alignment film material characterized by a pretilt angle that is about the middle of the pretilt angle in the region B, the regions A, The rising direction of the liquid crystal molecules differs for each B, and the same effect as in the first embodiment can be obtained. In this case, the pixel electrode may have the same shape as that of the third embodiment (described later).

In FIG. 6, the rubbing direction for the first substrate 11 is indicated by an arrow 111, and the rubbing direction for the second substrate 12 is indicated by an arrow 112. Further, the relative directions of the pretilt direction and the pretilt angle of the liquid crystal molecules in each of the minute regions A and B near the surface of each substrate are indicated by arrows 111H and 111H for the first substrate 11.
L, arrows 112H, 11 on the second substrate 12
Shown in 2L. Here, the pretilt angles indicated by arrows 111H and 112H are larger than the pretilt angles indicated by arrows 111L and 112L. Small areas A with different pretilt angles of liquid crystal molecules near each substrate surface
Similarly to the first embodiment, the boundary 22 between the pixel region 71 and the region B is a straight line parallel to the direction in which the gate bus line 55 extends, and crosses the substantially central portion of each pixel electrode 71 and the position of each pixel. The position is set 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 alignment process in different directions for each minute area on the same substrate, for example, as shown in FIG.
Steps (e) to (e) may be performed sequentially. First, as shown in FIG. 7A, a first alignment agent layer 35 made of an inorganic material and having 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 a two-layer structure including a second alignment agent layer 36 made of an organic material and having a high pretilt angle. Next, as shown in FIG. 7B, the alignment films 31 and 32 are formed.
A resist 40 is applied thereon, and a resist pattern is formed by photolithography so as to correspond to either the region A or the region B in FIG. Subsequently, FIG.
As shown in (c), according to the resist pattern, the second alignment agent layer 36 made of an organic material is partially removed to expose the first alignment agent layer 35 made of an inorganic material. Then, as shown in FIG.
Is removed. Finally, as shown in FIG. 7E, a rubbing process is performed in a certain direction. Thereby, the substrates 11 and 12 which have been subjected to the alignment treatment so that the magnitude of the pretilt angle near the surface differs for each of the minute regions A and B can be obtained.

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

In the liquid crystal display device according to the third embodiment, a portion where a reverse tilt domain is likely to be generated on the pixel electrode in the case of the alignment processing direction will be described below. In the liquid crystal display device according to the third embodiment, the rising direction of the liquid crystal molecules near the center of both substrates when a voltage is applied is small in the area A.
Corresponds to the direction opposite to the direction of pretilt 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 area of the liquid crystal display device of the third embodiment is opposite to the direction indicated by the arrow 121L in the area A. That is, in the region B, it can be said that the direction is indicated by the arrow 121H. Therefore,
Of the portions on the pixel electrode, the portion where the reverse tilt domain is likely to occur is indicated by an arrow 121L in each minute region.
And the part located behind the arrow 121H.

The liquid crystal display device of the third embodiment is also the same as that of the first embodiment.
Similarly to the above, in the planar shape of each pixel electrode 71, a cutout 74 is provided in alignment with the position of the boundary of the alignment processing section that crosses substantially the center of the pixel electrode 71. The shape of the cutout portion 74 is a shape that cuts out the above-described portion where the reverse tilt domain is likely to be generated on the pixel electrode, and is the same shape as that of the first embodiment. As with the first embodiment, the size of the notch 74 is 6 μm, 12 μm, and 1 μm.
The test was performed for three types of 8 μm.

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

Comparative Example 3 A liquid crystal display device having the same configuration as that of the third embodiment, except that the planar shape of each pixel electrode 71 is different from that of the third embodiment was manufactured. That is, the pixel electrode 71
Has no cutout in its planar shape, and the portion along the drain bus line 56 is linear. Otherwise, the configuration is the same as that of the third embodiment.

In the liquid crystal display device of Comparative Example 3, as in Comparative Example 1, the disclination 23 is provided so as to be shifted from the boundary position 22 of the alignment processing section and aligned with the boundary 22 of the alignment processing section. It has been confirmed that the light may protrude from the light-shielding portion 26 that has been generated. This greatly degrades the image quality.

Fourth Embodiment FIG. 8 shows the configuration of a liquid crystal display device according to a fourth embodiment. 9 and 10 both show the configuration of the liquid crystal display device of FIG.
FIG. 9 is a cross-sectional view taken along a cross section orthogonal to the direction in which the gate bus line 5 extends. FIG.
Shows the configuration in the cross section indicated by EE ′ in FIG.
FIG. 11 shows a configuration in a cross section indicated by FF 'in FIG. This liquid crystal display device has the same configuration as that shown in the first embodiment, but the minute regions A and B of both substrates 11 and 12 are arranged.
Of the rubbing process, the boundary position between the minute regions A and B, and the planar shape of the pixel electrode 71 are different from those shown in the first embodiment.

The first substrate 11 is indicated by an arrow 111 in FIG.
In the directions indicated by arrows a and 111b, the second substrate 12 is oriented in the directions indicated by arrows 112a and 112b in FIG. The boundary 22 between the region A and the region B (indicated by a dashed line) is a straight line parallel to the direction in which the gate bus line 55 extends, and a position crossing substantially the center 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 position is set so as to divide the width of the rectangle into approximately two equal parts. In a liquid crystal display device having no storage capacitor portion or a liquid crystal display device in which the storage capacitor terminal does not overlap the gate bus line,
The boundary 22 of the alignment processing section is a straight line parallel to the direction in which the gate bus line 55 extends, and passes through a position substantially crossing the center of each pixel electrode 71 and a center of the width of the gate bus line 55. The position may be used. Also in the fourth embodiment, by combining the alignment film materials having different pretilt angles as in the second embodiment, or by using the two-layer alignment film as in the third embodiment, Simplification is possible.

The liquid crystal display device of the fourth embodiment is also the same as that of the first embodiment.
In the same manner as described above, in order to prevent light leakage from the disclination, on the first substrate on which the pixel electrode 71 is provided, the first thin film layer formed of the same conductive thin film layer as the gate bus line 55 is formed. The light-shielding portion 26 is electrically insulated from the pixel electrode 71 by the insulating layer 57 (see FIGS. 10 and 11).

The shape of the pixel electrode 71 is such that it has a cutout 74 at a position matching the boundary of the alignment processing section that crosses substantially the center of the pixel electrode 71. The shape of the cutout portion 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 pixel electrode 71 is cut from both sides of the electrode 71. The position of the longitudinal center line of the cutout 74 coincides with the position of the boundary 22 of the alignment treatment section. Regarding the width of the cut portion in the direction orthogonal to the longitudinal direction, three types of 3 μm, 6 μm and 9 μm were used. The pixel electrode 71 is the same as the conductive thin film layer forming the drain bus line 56 at the constricted portion of the cutout 74 in order to prevent the pixel electrode 71 from being disconnected at the constricted portion of the cutout 74 and causing a defect. (See FIG. 11), which is composed of a thin film layer and is electrically connected to the pixel electrode 71.

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

First, a description will be given, with reference to FIG. 9, of a position at which disclination occurs in accordance with the boundary 22 of the alignment processing section set at a position passing on the gate bus line.
In this liquid crystal display device, when the shape of a portion where the drain bus line 56 or the storage capacitor terminal 58 does not overlap on the gate bus line 55 is roughly regarded as a rectangle, the width of the rectangle is almost equally divided into two. A boundary 22 of the alignment processing section is set at the position, and the liquid crystal molecules 21 on both sides of the alignment processing section are separated from the first substrate provided with the gate bus line 55 at the end opposite to the boundary side. Since the liquid crystal layer is aligned so as to rise in the direction away from the liquid crystal layer, the direction of the electric field applied to the liquid crystal layer matches the pretilt direction, and the disclination 23 is positioned at a predetermined position, that is, at the position of the boundary 22 of the liquid crystal alignment processing section. Fixed.

Next, a description will be given of the position where disclination occurs at the boundary of the alignment processing section that crosses substantially the center of the pixel electrode 71 with reference to FIG. In this liquid crystal display device, in the shape of the pixel electrode 71, the pixel electrode 71
A notch 74 is provided at a position matching the boundary of the alignment section crossing substantially the center of the pixel electrode 71. On both sides of the boundary of the alignment section, the liquid crystal molecules 21 have the edge on the boundary side thereof at the pixel electrode 71. Is oriented so that it rises in the direction away from the first substrate provided with, the direction of the electric field applied to the liquid crystal layer coincides with the pretilt direction, and the disclination 23 is placed at a predetermined position, that is, the liquid crystal. It is fixed at the position of the boundary 22 of the alignment section.

As described above, the disclination associated with the boundary 22 of the alignment processing section is fixed at a predetermined position, and therefore, as shown in FIG. 8, the disclination 23 is fixed at a predetermined position as a whole. As a result, it was confirmed that uniform and good image quality was obtained over the entire surface of the liquid crystal display device without protruding into the pixel opening. This was confirmed in each of the three types of cuts described above.

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

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

Embodiment 5 FIG. 13 shows the configuration of a liquid crystal display device of Embodiment 5. This liquid crystal display device has the same configuration as that shown in the fourth embodiment, but is a liquid crystal display device configured by a simplified process using a combination of different alignment film materials as shown in the second embodiment. That is, a material having a high pretilt angle is used for the alignment film 31 of the first substrate 11 on which the pixel electrode 71 is provided, and the alignment film 3 of the second substrate 12 on which the common electrode 72 is provided.
2 is made of a material having a low pretilt angle, and the second substrate 12 is subjected to an orientation treatment in a uniform direction.

In FIG. 13, the rubbing directions for the first substrate 11 are indicated by arrows 111a and 111b, and the rubbing directions for the second substrate 12 are indicated by arrows 11a and 11b.
Indicated by 2. The boundary 22 between the minute region A and the region B having different alignment processing directions (indicated by a dashed line) is similar to the fourth embodiment.
A straight line parallel to the direction in which the gate bus line 55 extends, a position crossing substantially the center of each pixel electrode 71 and a position passing over the gate bus line 55 are set.

In the liquid crystal display device according to the fifth embodiment, the planar shape of the pixel electrode 71 is also different from that of the fourth embodiment. That is, as shown in FIG.
The shape of the cutout 74 is such that 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 reverse tilt domains are likely to occur are chamfered. The corner where the reverse tilt domain is likely to occur is defined as the first substrate 1 in each of the minute regions A and B.
Arrows 111a, 111b indicating the orientation direction for 1
Is a corner located in a direction different from the tip direction. The shape of the chamfer was a diagonal straight line as shown in FIG. 13, and the size of the chamfer was measured for two types of diagonal sides of 3 μm and 6 μm.

In the liquid crystal display device according to the fifth embodiment, as shown in FIG.
Of the corners of the pixel electrode associated with No. 4, the boundary 22 of the alignment processing section crossing the pixel electrode in the liquid crystal display device according to the fourth embodiment.
Is chamfered at the corner where the disclination 23 is partially deviated from the boundary of the alignment processing section, so that the disc can be more accurately formed than in the liquid crystal display device of the fourth embodiment. The ligation 23 was fixed at the boundary between the alignment treatment sections. Therefore, it was confirmed that the disclination did not protrude into the pixel opening and 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 above-described three types of chamfers were applied. In addition,
The shape of the chamfer can be other shapes, such as an arc, for example.
Similar effects can be expected.

Embodiment 6 The configuration is the same as that of Embodiment 5, but the shape of the cutout 74 of each pixel electrode 71 is different from that of Embodiment 5.
A liquid crystal display device different from the above was manufactured. As shown in FIG. 14, the shape of the cutout 74 in the sixth embodiment is such that an elongated hole is formed so that its longitudinal direction is located along the boundary 22 of the alignment processing section set at a position crossing the pixel electrode 71. It has such a shape. Also, the notch 7
In accordance with the shape of No. 4, two anti-cut terminals 75 are provided for each pixel electrode. A part of the division preventing terminal 75 also serves as a light shielding part for disclination. Otherwise, the configuration is the same as that of the fifth embodiment.

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

Seventh Embodiment A liquid crystal display device having the same configuration as that of the second embodiment, except that the planar shape of each pixel electrode 71 is different from that of the second embodiment was manufactured. The planar shape of the pixel electrode in the seventh embodiment is, as shown in FIG.
In the side along one drain bus line 56, the shape is such that 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 a 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. Otherwise, the configuration is the same as that of the second embodiment. The distance between the side of the pixel electrode 71 and the drain bus line 56 was set to 8 μm at the above-described portion having a large interval, and was set to 5 μm at other portions.

In the structure according to the seventh 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 increased, the direction of the horizontal electric field generated at this portion is weakened. As a result, as shown in FIG. 16, the disclination generated at the boundary between the liquid crystal alignment processing sections was fixed at a predetermined position. Therefore, it was confirmed that the disclination did not protrude into the pixel opening, and uniform and good image quality was obtained over the entire surface of the liquid crystal display device.

Eighth Embodiment A liquid crystal display device having the same configuration as that of the second embodiment, except that the planar shape of each pixel electrode 71 is different from that of the second embodiment is manufactured. As shown in FIG. 16, the planar shape of the pixel electrode in the eighth embodiment has a cutout 74 similar to that in the second embodiment, and further, the side of the pixel electrode 71 along the drain bus line 56 has The deformed shape is such that 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 crossing 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. Otherwise, the configuration is the same as that of the second embodiment. The size of the cut portion is 8 as shown in FIG.
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 at the above-described portion having a large interval, and was set to 5 μm at other portions.

In the structure according to the eighth 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 increased, the direction of the horizontal electric field generated at this portion is weakened. As a result, as shown in FIG. 16, the disclination occurring at the boundary between the liquid crystal alignment processing sections 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 uniform and good image quality was obtained over the entire surface of the liquid crystal display device.

Ninth Embodiment A liquid crystal display device having the same configuration as that of the fifth embodiment, except that the planar shape of each pixel electrode 71 is different from that of the fifth embodiment was manufactured. The planar shape of the pixel electrode in the ninth embodiment is, as shown in FIG.
In the side along one drain bus line 56, the shape is such that 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 a 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. Otherwise, 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 at the above-described portion having a large interval, and was set to 5 μm at 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 increased, the direction of the horizontal electric field generated at this portion is weakened. As a result, as shown in FIG. 17, the disclination occurring at the boundary between the liquid crystal alignment processing sections was fixed at a predetermined position. Therefore, it was confirmed that the disclination did not protrude into the pixel opening, and uniform and good image quality was obtained over the entire surface of the liquid crystal display device.

<< Embodiment 10 >> The structure of a liquid crystal display device of Embodiment 10 is shown in FIG. This liquid crystal display device
Although the configuration is the same as that shown in the fifth embodiment, the arrangement of the active elements 40 corresponding to each pixel is different from that of the fifth embodiment.
In other words, among the minute regions where the alignment state of the liquid crystal 20 differs, the pretilt direction of the liquid crystal molecules near the surface of the first substrate 11 in the minute region (region B) where the active element is arranged, that is, the alignment process Arrow 111b indicating direction
The active element 40 is arranged at a position on the opposite side to the direction.

Hereinafter, effects of the configuration of the present embodiment will be described.

Also in the structure of the fifth embodiment, as shown in FIG. 19, a reverse tilt domain may be generated at a position near the surface of the first substrate 11 opposite to the pretilt direction. In the configuration of the tenth embodiment, FIG.
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 configuration 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 good image quality can be obtained over the entire surface of the liquid crystal display device.

<< Embodiment 11 >> FIG. 20 shows the configuration of a liquid crystal display device of Embodiment 11. This liquid crystal display device
The configuration is the same as that shown in the fifth embodiment, except that both substrates 1
The alignment processing directions for 1 and 12 and the twist 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 shown by 1b, the second substrate 12 is uniformly oriented in the direction shown by 112, and the liquid crystal 20 is added with a slight amount of a clockwise chiral agent. According to the effect of the chiral agent and the above-described alignment treatment direction, the liquid crystal molecules are substantially clockwise at right angles from the surface of the second substrate 12 on the near side to the surface of the first substrate 11 on the far side in FIG. It is twisted and oriented. Correspondingly, the cutout portion 74 of the pixel electrode 71 and the light shielding portion 26
Is also reversed left and right from the configuration shown in the fifth embodiment.

That is, also in the structure of the eleventh embodiment, as shown in FIG. 20, active elements are arranged at positions where a reverse tilt domain is likely to occur. Therefore,
Even when a reverse tilt domain is generated, 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, the uniformity is obtained over the entire surface of the liquid crystal display device. And good image quality can be obtained.

[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, a notch 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 the side thereof The distance between the gate bus line or the drain bus line along the line is different on both sides of the boundary of the alignment processing section that crosses the pixel electrode, which affects the direction in which liquid crystal molecules rise on the pixel electrode when voltage is applied. Weakening the lateral electric field that can be exerted, or actively utilizing the lateral electric field, the position of the disclination can be accurately fixed at a predetermined position, and thus a stable divided liquid crystal alignment can be obtained. it can. Therefore, it is possible to obtain a uniform and excellent display over the entire surface without disclination protruding into the pixel opening and deteriorating the image quality. In addition, if the disclination can be fixed accurately, the area of the light-shielding portion that conceals the disclination can be reduced, so that the decrease in the pixel aperture ratio due to the light-shielding portion can be minimized, and the overall brightness can be increased. Thus, a liquid crystal display device having excellent viewing angle characteristics can be provided. Further, according to the present invention, the above-described great effect can be obtained only by changing the shape of the pixel electrode without adding a new process to the entire manufacturing process, and the disclination or the cut portion of the pixel electrode can be obtained. Alternatively, even when a light-shielding portion for concealing both of them and a division prevention terminal for preventing division of a pixel electrode are formed, it is possible to form the same with an existing conductive thin film layer. And is preferable in terms of cost and yield.

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

[Brief description of the drawings]

FIG. 1 is a plan view illustrating a configuration of a liquid crystal display device according to a first embodiment.

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.

FIGS. 3 (a) to 3 (e) are views showing an alignment process for a substrate.

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

FIG. 5 is a plan view illustrating a configuration of a liquid crystal display device according to a second embodiment.

FIG. 6 is a plan view illustrating a configuration of a liquid crystal display device according to a third embodiment.

FIGS. 7A to 7E are diagrams each showing an alignment process for a substrate.

FIG. 8 is a plan view illustrating a configuration of a liquid crystal display device according to a fourth embodiment.

FIG. 9 is a cross-sectional view illustrating a configuration near a gate bus line of a liquid crystal display device according to a fourth embodiment.

FIG. 10 is a cross-sectional view illustrating a configuration of a central portion of a pixel electrode of a liquid crystal display device according to a fourth embodiment.

FIG. 11 is a cross-sectional view illustrating a configuration of a central portion of a pixel electrode of a liquid crystal display device according to a fourth embodiment.

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

FIG. 13 is a plan view illustrating a configuration of a liquid crystal display device according to a fifth embodiment.

FIG. 14 is a plan view illustrating a configuration of a liquid crystal display device according to a sixth embodiment.

FIG. 15 is a plan view illustrating a configuration of a liquid crystal display device according to a seventh embodiment.

FIG. 16 is a plan view illustrating a configuration of a liquid crystal display device according to an eighth embodiment.

FIG. 17 is a plan view illustrating a configuration of a liquid crystal display device according to a ninth embodiment.

FIG. 18 is a plan view illustrating a configuration of a liquid crystal display device according to a tenth embodiment.

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

FIG. 20 is a plan view illustrating a configuration of a liquid crystal display device according to an eleventh embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 1st board | substrate 12 2nd board | substrate 20 liquid crystal 21 liquid crystal molecule 22 boundary of the alignment process division 23 disclination 25 storage capacity part 26 light-shielding part 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 section 75 Split prevention terminal 80 Rubbing roller A, B area

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shigeyoshi Suzuki 5-7-1 Shiba, Minato-ku, Tokyo Inside NEC Corporation (72) Inventor Hideo Shibahara 5-7-1 Shiba, Minato-ku, Tokyo Japan Electric Co., Ltd. (72) Inventor Yoshihiko Hirai 5-7-1 Shiba, Minato-ku, Tokyo NEC Co., Ltd. (56) References JP-A-3-144420 (JP, A) JP-A-1-266512 ( JP, A) JP-A-6-43461 (JP, A) JP-A-8-129180 (JP, A)

Claims (23)

(57) [Claims] 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 and driving a corresponding pixel electrode; a gate bus line and a drain bus line provided on the first substrate and connected to each of the active elements; and the second substrate A common electrode provided thereon, and a liquid crystal sandwiched between the first substrate and the second substrate, such 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 alignment processing in accordance with the minute region, at least one of boundaries of the alignment processing section crosses the pixel electrode. positioned to, in alignment with at least one of the boundary of alignment processing sections positioned to cross the pixel electrode, the pixel electrode has at least one cut portion in its planar shape
The alignment processing section set at a position crossing the pixel electrode.
The first substrate aligned with at least one of the minute boundaries
Alternatively, on the second substrate or both substrates,
Disclination or the notch or
A liquid crystal display device comprising a light-shielding portion for concealing both of them . 2. The light-shielding portion is formed of the same layer as the conductive thin film layer forming the gate bus line, or is formed of the same layer as the conductive thin film layer forming the drain bus line. The liquid crystal display device according to claim 1 , wherein the liquid crystal display device is constituted by one or both of them. In the vicinity of at least one cut portion of the wherein the cut portion, wherein with split anti terminal electrically connected to the pixel electrode provided on said first substrate
3. The liquid crystal display device according to claim 1 or 2 . 4. The semiconductor device according to claim 1, wherein the division preventing terminal is formed of the same layer as a conductive thin film layer forming the gate bus line.
4. The liquid crystal display device according to claim 3 , wherein the liquid crystal display device is formed of the same layer as the conductive thin film layer forming the drain bus line, or is formed of both layers. 5. A liquid crystal display device of at least a part also serves as at least part of the light shielding portion according to claim 3 or claim 4, wherein said dividing prevention terminals. 6. A first substrate and a second substrate provided opposite to each other.
A substrate, provided in a matrix on the first substrate;
Pixel electrodes and at least one for each pixel electrode
Driving a corresponding pixel electrode provided on the first substrate;
Active elements provided on the first substrate and the active elements provided on the first substrate.
Gate bus lines and drains to which elements are connected respectively
Bus line and a common line provided on the second substrate.
A pole and a pinch between the first substrate and the second substrate
Liquid crystal, and the alignment state of the liquid crystal is different for each minute region,
At least one of the first substrate and the second substrate is
Orientation treatment is performed in accordance with the minute area.
In a liquid crystal display device, at least one of the boundaries of the alignment processing section connects the pixel electrode.
The alignment processing section positioned to traverse and to traverse the pixel electrode
The pixel electrode is aligned with at least one of the
Having at least one notch in the planar shape of
The alignment processing section positioned so as to cross the pixel electrode.
Each minute on both sides of at least one of the boundaries of
Liquid crystal molecules near the center between the two substrates
When pressure is applied, the side closer to the boundary among the two ends of the liquid crystal molecule
Of the first substrate rises in a direction away from the first substrate
As described above, the alignment treatment is performed , and at least one of the cut portions has an elongated shape such that a longitudinal direction of the cut portion is located along a boundary of the alignment processing section. Display device. 7. In at least one of the elongated cut portions, a position of a longitudinal center line of the cut portion substantially coincides with a boundary position of the alignment treatment section.
7. The liquid crystal display device according to 6 . Wherein said at least one shape of the cut portion is an elongated shape, the liquid crystal display device of an elongate holes shapes claim 6 or claim 7, wherein the pixel electrode. 9. At least one of the shape of the cut portion and the an elongated shape, claim 6 or claim from one or both sides of the pixel electrode along the boundary of the alignment process segment is shaped to cut a pixel electrode 8. The liquid crystal display device according to 7 . 10. At least one of the corners of the pixel electrode associated with the notch which has a shape that cuts the pixel electrode from both sides or one side of the pixel electrode along the boundary of the alignment processing section. The liquid crystal display device according to claim 9 , wherein chamfering is performed on the liquid crystal display device. 11. A method according to claim 1, wherein at least one of the minute regions is located in a direction different from a longitudinal direction of liquid crystal molecules on the surface of the first substrate among corners of the pixel electrode associated with the cutout. The liquid crystal display device according to claim 10, wherein the corners are chamfered. 12. At least one of the boundaries of the alignment processing section is set along the direction in which the gate bus line extends, and at least a part thereof 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 center between the two substrates, when a voltage is applied, the ends of the both ends of the liquid crystal molecules near the boundary are the first ends. so as to rise in a direction away from the substrate, the liquid crystal display device according to claim 1 to claim 11, wherein said alignment treatment is performed. 13. A storage capacitor terminal provided on the first substrate for each of the pixel electrodes and / or for each of the pixel electrodes and connected to the pixel electrode, and / or an active capacitor for driving the pixel electrode. For a gate bus line different from the gate bus line connected to the element, a storage capacitor portion is formed having an overlapping portion via an insulating layer, and at least along a direction in which the gate bus line extends and At least one of the boundaries of the alignment processing section, a part of 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 that drives the pixel electrode. 13. The liquid crystal display device according to claim 12 , provided between the liquid crystal display device and the gate bus line. 14. At least one of the boundaries of the alignment processing 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, the liquid crystal molecules near the center between the two substrates, when a voltage is applied, the ends of the two ends of the liquid crystal molecules farthest from the boundary move away from the first substrate. The said alignment process is performed so that it may stand up, The claim 1-Claim 1
2. The liquid crystal display device according to 1 . 15. A boundary of said alignment processing section, which is set so as to extend along a direction in which said gate bus line extends and at least a part thereof is located on said gate bus line, comprises a gate of said gate bus line. 15. The liquid crystal display device according to claim 14 , wherein the liquid crystal display device passes through a substantially central portion of a width in a direction orthogonal to a direction in which the bus line extends. 16. A storage capacitor terminal provided on the first substrate for each of the pixel electrodes and / or for each of the pixel electrodes and connected to the pixel electrode, and / or an active capacitor for driving the pixel electrode. For a gate bus line different from the gate bus line connected to the element, a storage capacitor portion is formed having an overlapping portion via an insulating layer, and at least along a direction in which the gate bus line extends and A part of the boundary of the alignment processing section, which is set so as to be located on the gate bus line, is a portion where other wirings or electrodes such as a drain bus line or a storage capacitor terminal do not overlap on the gate bus line. claims the shape is set to be substantially bisects that position the width of the rectangle when regarded as roughly rectangular 14
The liquid crystal display device as described in the above. 17. A first substrate and a second substrate provided opposite to each other.
A substrate, a pixel electrode provided in a matrix on the first substrate, and an active element provided on the first substrate for driving the corresponding pixel electrode at least one for each pixel electrode, A gate bus line and a drain bus line provided on the first substrate and connected to each of the active elements, a common electrode provided on the second substrate, the first substrate and the second And a liquid crystal sandwiched between substrates, such 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 alignment processing in accordance with the minute region, at least one of boundaries of the alignment processing section crosses the pixel electrode. At least one of the sides of the pixel electrode, at least one of the boundaries of the alignment processing section crosses and extends along the direction in which the gate bus line or the drain bus line extends. Is a deformed shape in which 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 processing section , and is set at a position crossing the pixel electrode. The alignment treatment section
The first substrate aligned with at least one of the minute boundaries
Alternatively, on the second substrate or both substrates,
There is a light blocking part to hide the disclination.
The liquid crystal display device, characterized in that that. 18. The light-shielding portion is formed of the same layer as the conductive thin film layer forming the gate bus line, or is formed of the same layer as the conductive thin film layer forming the drain bus line. 18. The liquid crystal display device according to claim 17 , comprising: or both. 19. At least one of the boundaries of the alignment processing section is set along the direction in which the gate bus line extends, and at least a part thereof 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 center between the two substrates, when a voltage is applied, the ends of the both ends of the liquid crystal molecules near the boundary are the first ends. so as to rise in a direction away from the substrate, the liquid crystal display device according to claim 17 to claim 18, wherein said alignment treatment is performed. 20. A storage capacitor terminal provided on the first substrate for each of the pixel electrodes and / or for each of the pixel electrodes and connected to the pixel electrode, and / or a storage capacitor terminal for driving the pixel electrode. For a gate bus line different from the gate bus line connected to the element, a storage capacitor portion is formed having an overlapping portion via an insulating layer, and at least along a direction in which the gate bus line extends and At least one of the boundaries of the alignment processing section, a part of 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 that drives the pixel electrode. 20. The liquid crystal display device according to claim 19, which is provided between the liquid crystal display device and a gate bus line. 21. At least one of the boundaries of the alignment processing section is set so as to be 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, the liquid crystal molecules near the center between the two substrates, when a voltage is applied, the ends of the two ends of the liquid crystal molecules farthest from the boundary move away from the first substrate. as rise, claims 17 to claim, wherein the alignment treatment is performed
19. The liquid crystal display device according to 18 . 22. A boundary of the alignment processing section, which is set so as to be along an extending direction of the gate bus line and at least a part thereof is located on the gate bus line, a gate of the gate bus line, 22. The liquid crystal display device according to claim 21 , wherein the liquid crystal display device passes through a substantially central portion of a width in a direction orthogonal to a direction in which the bus line extends. 23. A storage capacitor terminal provided on the first substrate for each of the pixel electrodes and / or for each of the pixel electrodes and connected to the pixel electrode, and / or an active capacitor for driving the pixel electrode. For a gate bus line different from the gate bus line connected to the element, a storage capacitor portion is formed having an overlapping portion via an insulating layer, and at least along a direction in which the gate bus line extends and A part of the boundary of the alignment processing section, which is set so as to be located on the gate bus line, is a portion where other wirings or electrodes such as a drain bus line or a storage capacitor terminal do not overlap on the gate bus line. 22. The position is set so as to substantially divide the width of the rectangle when the shape of the rectangle is roughly regarded as a rectangle.
The liquid crystal display device as described in the above.