JP2016173514A - Liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display element with high display quality.SOLUTION: A liquid crystal display element includes: a first substrate including a first electrode and a first vertical alignment film not subjected to the alignment process; a second substrate including a second electrode and a second vertical alignment film not subjected to the alignment process; a liquid crystal layer disposed between the first and second substrates; and spherical spacers for keeping the first and second substrates apart from each other with a certain distance and horizontally aligning liquid crystal molecules of the liquid crystal layer on a surface. The first and second electrodes include an opening. When the first and second substrates are viewed in a normal line direction, at least one of the opening of the first electrode and the opening of the second electrode includes a plurality of zigzag shaped openings extending in a first direction as a whole. The distance between the edges of the two zigzag shaped openings adjacent in a second direction orthogonal to the first direction is 30 μm or less. The spherical spacers have a diameter of 2.5 μm to 6.0 μm and are disposed between the first substrate and the second substrate at a density of 56 pieces/mmφ to 191 pieces/mmφ. The liquid crystal display element is a four-domain element.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a liquid crystal display element.

  In a vertical alignment type liquid crystal display element in which a liquid crystal layer in which liquid crystal molecules are aligned substantially perpendicular to the substrate surface is disposed between transparent substrates, the retardation in the liquid crystal layer is almost zero. For this reason, the transmittance | permeability equivalent to the case where two polarizing plates are piled up on cross Nicol can be acquired by arrange | positioning a polarizing plate in a cross Nicol on the opposite side to the liquid crystal layer of both board | substrates. That is, a high contrast normally black display can be realized easily.

  In a vertical alignment type liquid crystal display element, a liquid crystal layer is formed using a liquid crystal material having a negative dielectric anisotropy, and a vertical alignment film is disposed on a substrate surface close to the liquid crystal layer. When a voltage higher than the threshold voltage of the liquid crystal material is applied between the electrodes arranged on both substrates sandwiching the liquid crystal layer, for example, the liquid crystal molecules located at the center in the thickness direction of the liquid crystal layer are inclined with respect to the substrate surface. To do. However, when the liquid crystal molecules are aligned completely perpendicular to the substrate when no voltage is applied, a uniform alignment state cannot be obtained within the surface of the liquid crystal display element, resulting in non-uniform display.

  For example, an invention of a liquid crystal display element that realizes display uniformity by providing slit-like openings in electrodes for such non-uniform display has been disclosed (for example, see Patent Documents 1 to 4).

  In recent color TFT liquid crystal display elements, resin-made columnar spacers that hold both substrates at regular intervals are regularly and periodically arranged on the color filter substrate side facing the TFT array substrate. The columnar spacer is formed at the same time as the color filter, for example, in the step of forming the color filter on the substrate. In the case of a monochrome display type liquid crystal display element that does not use a color filter, spherical or columnar spacers are uniformly distributed in the substrate surface so that the number per unit area is appropriate.

  The spacer is an epoxy resin, phenol resin, melamine resin, unsaturated polyester resin, divinylbenzene copolymer, divinylbenzene-styrene copolymer, divinylbenzene-acrylic ester copolymer, diallyl phthalate, allyl isocyanurate polymer, and And a crosslinkable synthetic resin such as a benzoguanamine polymer (see, for example, Patent Document 5).

  In a horizontal alignment type liquid crystal display element, it is known that light leakage occurs around the spacer when no voltage is applied. This light leakage phenomenon can be reduced by modifying the spacer surface to the vertical alignment (see, for example, Patent Document 6). The vertical alignment can be modified by, for example, forming a coating layer on the spacer surface with polyimide or an organic silane compound (see, for example, Patent Document 7).

  However, the formation of the coating layer causes an increase in lead time and cost.

  On the other hand, in the vertical alignment type liquid crystal display element having an electrode in which slit-like openings are formed, the inventor of the present application tends to partially agglomerate spacers scattered in the substrate surface when the substrate interval is 3 μm or less. In response to the problem that the agglomerated part causes display unevenness when a voltage is applied, a liquid crystal material with a specific chiral agent added is used, and further, it is operated under specific multiplex driving conditions, thereby suppressing display unevenness in appearance observation. (See, for example, Patent Document 8).

  However, the addition of the chiral agent deteriorates the steepness in the electro-optical characteristics of the liquid crystal layer, so that the light display transmittance and contrast of the liquid crystal display element are lowered. In addition, since the multiplex drive is performed under conditions deviating from the optimum bias drive for obtaining the best contrast, the display quality of the liquid crystal display element is further deteriorated.

Japanese Patent No. 4107978 Japanese Patent No. 4884176 JP 2012-63711 A Chinese Patent No. 10147280 JP-A-5-333348 Japanese Patent Laid-Open No. 5-232478 JP-A-6-11719 JP 2011-22486 A

  The inventor of the present application is a vertical alignment type liquid crystal display element in which a slit-like opening is formed on at least one of the electrode surfaces of the substrate (an oblique electric field generated around the opening when a voltage is applied, and the liquid crystal molecules in the liquid crystal layer are In a multi-domain vertical alignment type liquid crystal display device that controls alignment, display irregularities (such as roughness) appear when applying voltage (bright display), and this display irregularity appears in a band-shaped dark region near the spacer. I discovered that it was caused. This display non-uniformity does not occur, for example, when a spacer whose surface is modified to a vertical alignment is used, but occurs in a liquid crystal display element using a spacer that has not been modified.

FIG. 1 shows a band-like dark region according to the discovery of the present inventor. In the configuration in which the vertical alignment type liquid crystal display element is disposed between the crossed Nicols polarizing plates, when a voltage is applied, a dark region reflecting the shape of the spacer is used at the spacer arrangement position, for example, a circular spacer is used. (punctate granular) dark region D ₁ of the can is formed. This is because light is not transmitted at the spacer arrangement position.

Separately inventors to this, the surrounding of the dark region D _1, i.e. at least partly around the spacer, the dark region D ₂ and found that occurring in the strip. The belt-like dark region D ₂ is not formed around all the dark regions D ₁ (spacers), but is formed around some dark regions D ₁ (spacers).

Relates occurrence reason for strip dark region D _2, the present inventors have considered as follows. The inventor's consideration will be described with reference to FIGS. 2A to 2D.

  FIG. 2A is a schematic cross-sectional view showing the alignment of liquid crystal molecules in the course of injecting a liquid crystal material between the front and back substrates in the manufacturing process of the vertical alignment type liquid crystal display element.

  Each of the back and front substrates includes, for example, (i) a glass substrate, (ii) a transparent electrode having a slit-like opening formed on the glass substrate, and (iii) a vertical alignment film formed so as to cover the transparent electrode. Have. In this figure, only the front substrate 50 having a glass substrate 51, a transparent electrode 52 formed on the glass substrate 51 and having a slit-shaped opening 52 a, and a vertical alignment film 53 formed so as to cover the transparent electrode 52. The back side substrate was omitted.

  Spacers 54 are arranged between the back and front substrates, and the back and front substrates are held at a constant interval, for example. As an example, the liquid crystal material is injected between the front and back substrates on which the spacers 54 are disposed by using a vacuum injection method. A liquid crystal layer 55 is formed between the front and back substrates by the injected liquid crystal material.

  For example, a liquid crystal material is injected into the space 56 in a vacuum state. In this figure, the liquid crystal injection direction is indicated by an arrow.

  At the time of liquid crystal injection, the alignment state of the liquid crystal molecules is determined by the vertical alignment film disposed on the front and back substrate surfaces. Therefore, the alignment state in the liquid crystal layer 55 is uniform (perpendicular to the substrate surface). Conceivable.

  FIG. 2B is a schematic cross-sectional view showing liquid crystal molecule alignment immediately after the liquid crystal material injection between the front and back substrates is completed. The liquid crystal molecules are aligned horizontally (so as to be parallel to the surface) on the surface of the spacer 54. An alignment state between the alignment uniform region A of the liquid crystal molecules (region where the liquid crystal molecules align perpendicular to the substrate surface when no voltage is applied) and the region B aligned along the surface of the spacer 54 is in an intermediate state. Region C is formed.

  FIG. 2C shows a liquid crystal molecule alignment state in the liquid crystal layer 55 when a voltage is applied. When a voltage is applied, an oblique electric field (shown by an arrow) is generated in the vicinity of the slit-shaped opening 52a, and the liquid crystal molecules are inclined so as to be orthogonal to the electric field direction.

For example, as shown in this figure, in the liquid crystal layer 55 around the spacer 54 at a position where the distance from the slit-shaped opening 52a is relatively short, the influence of the oblique electric field extends to the vicinity of the surface of the spacer 54. orientation uniform regions a ₂ when a voltage is applied is formed to the vicinity of the surface of the spacer 54. As a result, regions aligned along the spacer 54 surface B, and the region C is reduced as the alignment state between regions A ₂ and the region B (the effect of alignment control of liquid crystal molecules by the spacer 54 decreases). For this reason, display unevenness is not recognized in appearance observation.

However, as shown in FIG. 2D, in the liquid crystal layer 55 around the spacer 54 at a position where the distance from the slit-shaped opening 52a is relatively long, the influence of the oblique electric field (shown by an arrow) is It does not reach the vicinity of the surface. For this reason, the nonuniform alignment region C is formed in the vicinity of the surface of the spacer 54, and the region D in which the liquid crystal molecules are not inclined is formed around the region C (on the side opposite to the spacer 54) despite the application of voltage. The The region D is caused, at least partly around the spacer 54, the dark region D ₂ is generated, causing display unevenness in appearance observed.

Thus, band-like dark region D ₂ is, for example considered a distance between the slit opening 52a is formed around the spacer 54 in a relatively long position.

  An object of the present invention is to provide a liquid crystal display element with high display quality.

  According to an aspect of the present invention, a first substrate including a first electrode and a first vertical alignment film that is formed so as to cover the first electrode and that is not subjected to alignment treatment; A second substrate provided with a second electrode and a second vertical alignment film that is formed so as to cover the second electrode and that is not subjected to alignment treatment, and is disposed to face the first substrate substantially in parallel. And a liquid crystal layer disposed between the first substrate and the second substrate, and a constant distance between the first substrate and the second substrate, the surface of the liquid crystal layer being A spherical spacer for horizontally aligning liquid crystal molecules, wherein the first electrode and the second electrode have openings, and when viewed from the normal direction of the first and second substrates, the first electrode A jig extending in the first direction as a whole at least one of the opening of the electrode and the opening of the second electrode A plurality of zigzag openings are formed, the distance between the edges of two zigzag openings adjacent in the second direction orthogonal to the first direction is 30 μm or less, and the spherical spacer has a diameter of 2 There is provided a four-domain liquid crystal display element disposed between the first substrate and the second substrate at a density of 0.5 μm to 6.0 μm and a density of 56 / mmφ to 191 / mmφ. (See, for example, FIG. 3B and FIGS. 4A-4C).

  In this four-domain liquid crystal display element, when viewed from the normal direction of the first and second substrates, the opening of the first electrode and the opening of the second electrode are both as a whole. A zigzag-shaped opening extending in the first direction, including a liquid crystal display element in which zigzag-shaped bent portions are aligned in the second direction and are alternately arranged along the second direction is included. (See, for example, FIG. 4A) Further, when viewed from the normal direction of the first and second substrates, the opening of the first electrode and the opening of the second electrode are further zigzag shaped. A branch-like opening extending in parallel with the second direction is provided from each bent part in the convex direction of the bent part, and the branch-like opening is a zigzag-shaped opening adjacent to the second direction. A liquid crystal display element overlapping the bent portion is included (see, for example, FIG. 3B).

  In the four-domain liquid crystal display element, when viewed from the normal direction of the first and second substrates, the opening of the first electrode and the opening of the second electrode are both A V-shaped opening in which the second direction is a convex direction is an opening arranged so that the center of gravity is in a checkered pattern, and the V-shaped opening of the first electrode and the second electrode The V-shaped opening includes a liquid crystal display element in which zigzag-shaped openings extending in the first direction as a whole are formed so as to overlap with each other in the first direction and overlap at the end. (See, for example, FIG. 4B).

  Further, in the above four-domain liquid crystal display element, the opening of the first electrode and the opening of the second electrode both have a first branch opening extending in the third direction, A second branch opening extending in the fourth direction is used, and the first and second branch openings are on the first and second electrodes along the first direction. When viewed, the rows in which only the first branch openings are arranged and the rows in which only the second branch openings are alternately appear, and when viewed along the second direction, A line in which only the first branch opening is disposed and a line in which only the second branch opening is disposed are alternately formed, and the normal lines of the first and second substrates are formed. When viewed from the direction, the first branch opening of the first electrode and the second branch opening of the second electrode alternately overlap at the end, A zigzag-shaped first opening extending in the first direction is formed, and the first opening and the zigzag-shaped second opening adjacent to the second direction are A liquid crystal display element in which the second branch opening of one electrode and the first branch opening of the second electrode are alternately overlapped at the end (for example, FIG. 4C). reference).

  According to another aspect of the present invention, a first substrate including a first electrode and a first vertical alignment film formed so as to cover the first electrode and not subjected to alignment treatment And a second electrode and a second vertical alignment film that is formed so as to cover the second electrode and that has not been subjected to an alignment treatment. Two substrates, a liquid crystal layer disposed between the first substrate and the second substrate, and a constant distance between the first substrate and the second substrate, A spherical spacer for horizontally aligning liquid crystal molecules of the liquid crystal layer, the first electrode having a first opening that is long in the first direction, and a second direction orthogonal to the first direction. The first openings are arranged such that long second openings are alternately arranged in both the first direction and the second direction. Are formed at a constant pitch in the second direction and extend in the first direction through the center in the width direction of the first opening when viewed from the normal direction of the first and second substrates. An imaginary straight line and a virtual straight line extending in the second direction through the center in the width direction of the second opening, each having two sides in the first direction and the second direction. And a plurality of rectangular regions arranged adjacent to each other in the first direction and the second direction are defined, and the second electrode has a central portion of each of the plurality of rectangular regions. An opening is formed so as to be disposed, and the first electrode is disposed at an edge of the opening of the first electrode and constitutes a part of the four sides of the rectangular region, and the first portion is disposed at the center of the rectangular region. The distance between the edge of the opening of the two electrodes is 20 μm or less, and the spherical spacer has a diameter of 2.5 μm. A liquid crystal display element disposed between the first substrate and the second substrate at a density of ˜4.0 μm and a density of 56 pcs / mmφ to 191 pcs / mmφ is provided (for example, FIG. 4D reference).

  Furthermore, according to another aspect of the present invention, a first substrate including a first electrode and a first vertical alignment film formed so as to cover the first electrode and not subjected to alignment treatment And a second electrode and a second vertical alignment film that is formed so as to cover the second electrode and that has not been subjected to an alignment treatment. Two substrates, a liquid crystal layer disposed between the first substrate and the second substrate, and a constant distance between the first substrate and the second substrate, A spherical spacer for horizontally aligning the liquid crystal molecules of the liquid crystal layer, and the first electrode includes a first branch opening that is long in the first direction and a second perpendicular to the first direction. A second branch opening that is long in the direction is formed at the center of one edge in the length direction of the first branch opening and the length of the second branch opening. Two T-shaped openings formed by joining end portions in the direction have a constant pitch in each of the first direction and the second direction and are adjacent to the first direction. When viewed from the opening row, it is formed so as to be shifted by a half pitch in the second direction, and when viewed from the normal direction of the first and second substrates, the center in the width direction of the first branch-shaped opening. An imaginary straight line extending in the first direction through the imaginary straight line and a imaginary straight line extending in the second direction through the center in the width direction of the second branch opening. A plurality of rectangular regions having two sides in each of the direction and the second direction and arranged adjacent to the first direction and the second direction are defined, and the second electrode includes An opening is formed so as to be arranged at the center of each of the rectangular regions, and a part of the four sides of the rectangular region The distance between the edge of the T-shaped opening of the first electrode to be configured and the edge of the opening of the second electrode arranged at the center of the rectangular region is 35 μm or less, The spherical spacer has a diameter of 3.0 μm to 4.0 μm and a density of 56 / mmφ to 105 / mmφ and is disposed between the first substrate and the second substrate. An element is provided (see FIG. 4E).

  According to another aspect of the present invention, a first substrate including a first electrode and a first vertical alignment film formed so as to cover the first electrode and not subjected to alignment treatment And a second electrode and a second vertical alignment film that is formed so as to cover the second electrode and that has not been subjected to an alignment treatment. Two substrates, a liquid crystal layer disposed between the first substrate and the second substrate, and a constant distance between the first substrate and the second substrate, A spherical spacer for horizontally aligning the liquid crystal molecules of the liquid crystal layer, and the first electrode includes a first branch opening that is long in the first direction and a second perpendicular to the first direction. A second branch opening that is long in the direction is formed at the center of one edge in the length direction of the first branch opening and the length of the second branch opening. Two T-shaped openings formed by joining end portions in the direction have a constant pitch in each of the first direction and the second direction and are adjacent to the first direction. When viewing the opening row, the first row portion and the second portion are formed so as to be shifted in a predetermined pitch in the second direction after being arranged in the opposite directions along the second direction in units of rows. When viewed from the normal direction of the substrate, an imaginary straight line extending in the first direction through the center in the width direction of the first branch opening, and in the width direction of the second branch opening. An imaginary straight line extending through the center in the second direction, each having two sides in the first direction and the second direction, adjacent to the first direction and the second direction A plurality of rectangular regions are defined, and the second electrode includes a central portion of each of the rectangular regions. An opening is formed so as to be arranged, and is arranged at the edge of the T-shaped opening of the first electrode constituting a part of the four sides of the rectangular region and at the center of the rectangular region. The distance from the edge of the opening of the second electrode is 35 μm or less, the spherical spacer has a diameter of 2.5 μm to 6.0 μm, and a density of 56 / mmφ to 191 / mmφ. Thus, a liquid crystal display element disposed between the first substrate and the second substrate is provided (see, for example, FIG. 4F).

  Furthermore, according to another aspect of the present invention, a first substrate including a first electrode and a first vertical alignment film formed so as to cover the first electrode and not subjected to alignment treatment And a second electrode and a second vertical alignment film that is formed so as to cover the second electrode and that has not been subjected to an alignment treatment. Two substrates, a liquid crystal layer disposed between the first substrate and the second substrate, and a constant distance between the first substrate and the second substrate, A spherical spacer for horizontally aligning liquid crystal molecules of the liquid crystal layer, and the first electrode includes a first branch opening extending in the first direction and a second perpendicular to the first direction. An L-shaped opening composed of a second branch-shaped opening extending in the direction has the first direction and the second direction. Each of the first and second substrates is formed in a lattice shape at a constant pitch, and when viewed from the normal direction of the first and second substrates, passes through the center in the width direction of the first branch opening in the first direction. An imaginary straight line that extends and a imaginary straight line that extends in the second direction through the center in the width direction of the second branch-shaped opening, respectively, in the first direction and the second direction, respectively. A plurality of rectangular regions that have two sides and are arranged adjacent to each other in the first direction and the second direction are defined, and the distance between the edges of the openings that constitute the opposite sides of the rectangular region is The spherical spacer has a diameter of 3.0 μm to 4.0 μm and a density of 56 / mmφ to 105 / mmφ between the first substrate and the second substrate. Arranged liquid crystal display elements are provided (see, eg, FIG. 4G).

  According to the present invention, a liquid crystal display element with high display quality can be provided.

FIG. 1 is a schematic plan view showing a belt-like dark region according to the discovery of the present inventor. Figure 2A~ Figure 2D is a schematic cross-sectional view illustrating a discussion of the present inventors on the occurrence reason for the band-like dark region D _2. 3A is a schematic cross-sectional view showing a liquid crystal display device according to an embodiment, FIG. 3B is a schematic plan view showing a front-side transparent electrode 12 and a back-side transparent electrode 22, and FIG. 3C is according to the embodiment. It is a microscope observation image (alignment structure image) at the time of the voltage application of a liquid crystal display element. 4A to 4C are schematic plan views showing examples of electrode patterns (opening pattern) of the manufactured liquid crystal display element. 4D to 4F are schematic plan views showing examples of electrode patterns (opening pattern) of the manufactured liquid crystal display element. 4G and 4H are schematic plan views showing examples of electrode patterns (opening pattern) of the manufactured liquid crystal display element. FIG. 5 is a table showing the appearance observation results for the display of the vertical alignment type liquid crystal display element having the electrode structure shown in FIGS. 4A to 4H. FIG. 6 is a table showing the appearance observation results for the display of the vertical alignment type liquid crystal display device having the electrode structure shown in FIGS. 3B and 4D to 4H. FIG. 7 is a microscopic observation image (alignment structure image) when a voltage is applied to the vertical alignment type liquid crystal display element having the electrode structure of FIGS. 3B, 4D, 4G, and 4H.

  FIG. 3A is a schematic cross-sectional view illustrating a liquid crystal display device according to an embodiment. The liquid crystal display device according to the embodiment is a vertical alignment type liquid crystal display device in which slit-like openings are formed on the electrode surface of the substrate (liquid crystal molecules in the liquid crystal layer using an oblique electric field generated around the openings when a voltage is applied). A multi-domain vertical alignment type liquid crystal display element for controlling the alignment of the liquid crystal.

  The liquid crystal display element shown in FIG. 3A includes a front substrate 10, a rear substrate 20, a spherical spacer 31 that holds the substrates 10, 20 at a fixed interval, and both substrates 10, 20. The liquid crystal layer 30 is disposed between them.

  The front side substrate 10 includes a front side transparent substrate 11, a front side transparent electrode 12 formed on the front side transparent substrate 11, and a front side vertical alignment film 13 formed so as to cover the front side transparent electrode 12. Similarly, the back side substrate 20 includes a back side transparent substrate 21, a back side transparent electrode 22 formed on the back side transparent substrate 21, and a back side vertical alignment film 23 formed so as to cover the back side transparent electrode 22. The transparent substrates 11 and 21 are made of glass, for example. The transparent electrodes 12 and 22 are made of a transparent conductive material such as ITO, for example. The transparent electrodes 12 and 22 are patterned so as to have slit-shaped openings 12a and 22a, respectively. An insulating film may be formed on the transparent electrodes 12 and 22.

  In the display area defined within the surfaces 10 and 20 of the liquid crystal display element, for example, desired symbols and numbers are displayed. The slit-shaped openings 12a and 22a are formed only on the transparent electrodes 12 and 22 in the display area.

  The front side vertical alignment film 13 and the back side vertical alignment film 23 are not subjected to an alignment process such as a rubbing process. Therefore, when no voltage is applied, the liquid crystal molecules in contact with the substrates 10 and 20 (vertical alignment films 13 and 23) are completely vertically aligned.

  The liquid crystal layer 30 is configured using a nematic liquid crystal material having a negative dielectric anisotropy and having no added chiral agent.

  The spacers 31 arranged between the front substrate 10 and the back substrate 20 are spherical fine particles formed of, for example, a synthetic resin. The spacer 31 is not subjected to a surface modification process for vertical alignment. That is, on the surface of the spacer 31, the liquid crystal molecules are aligned horizontally (so as to be parallel to the surface of the spacer 31). In the embodiment, a spacer having a particle diameter of 4 μm manufactured by ibonding was used as the spacer 31. The spacers 31 are arranged in the planes of the substrates 10 and 20 with a uniform density. In the example, the dispersion density of the spacers 31 was 56 / mmφ.

  A front-side polarizing plate 41 and a back-side polarizing plate 42 are arranged in crossed Nicols on the surface opposite to the liquid crystal layer 30 of the front-side substrate 10 and the back-side substrate 20.

  A drive circuit 43 for switching the liquid crystal molecular arrangement of the liquid crystal layer 30 is connected between the two substrates 10 and 20 (both electrodes 12 and 22). The drive circuit 43 applies an electric signal between the electrodes 12 and 22 and multiplex-drives the liquid crystal display element by, for example, optimum bias drive that can obtain the best contrast.

  FIG. 3B is a schematic plan view showing the front transparent electrode 12 and the back transparent electrode 22. A plurality of slit-shaped openings 12a and 22a are formed in the electrodes 12 and 22, respectively. The slit-shaped openings 12a and 22a have the same shape. In the in-plane direction of the substrates 10 and 20, the X-axis direction (0 ° -180 ° direction, row direction), the Y-axis direction (90 ° -270 ° direction, column direction), and the normal direction of the substrates 10, 20 Z When defining the axial direction, each slit-shaped opening 12a, 22a extends in the X-axis direction as a whole. In addition, in this specification, the slit-shaped opening part 12a of the front side transparent electrode 12 is shown as a continuous line, and the slit-like opening part 22a of the back side transparent electrode 22 is shown with a broken line.

Each of the slit-shaped openings 12a and 22a is composed of branch portions (rectangular openings) br _{1 to} br _{3 having} a width of 10 μm that are regularly arranged. The branch part br ₁ is an opening having a length of about 150 μm extending in the direction of 135 ° to 315 °. The branch part br ₂ is an opening having a length of about 150 μm extending in the 45 ° -225 ° direction. Branches br ₁ and branch br ₂ is coupled alternately to each other in the end. Further, at the coupling position of the branch part br ₁ and the branch part br ₂ (bent part of the slit-like opening parts 12a and 22a), an opening part having a length of about 42 μm extending in the Y-axis direction in the convex direction of the bent part ( A branch br ₃ ) is arranged. The branch portions br _{1 to} br ₃ extend from the respective bent portions of the slit-shaped openings 12 a and 22 a in the direction of 120 ° with respect to each other.

In the front transparent electrode 12, a plurality of slit-shaped openings 12a are regularly arranged at regular intervals so that the positions of the bent portions are aligned along the Y-axis direction. Specifically, when viewed along the Y-axis direction, they are arranged at regular intervals with a distance of about 100 μm between the branch parts br ₁ (between the branch parts br ₂ ).

  The formation mode of the slit-like opening 22 a in the back side transparent electrode 22 is equal to the formation mode of the slit-like opening 12 a in the front side transparent electrode 12.

When viewed from the Z-axis direction (substrate 10, 20 normal direction), the slit-shaped openings 12a and the slit-shaped openings 22a are alternately arranged along the Y-axis direction. Further, the bent portion of the slit-shaped opening 12a and the bent portion of the slit-shaped opening 22a are aligned along the Y-axis direction. Further, the distance between the bent portion of the slit-shaped opening 12a adjacent to the Y-axis direction and the bent portion of the slit-shaped opening 22a is constant (about 42 μm in the Y-axis direction). That is, the slit-shaped opening 12a and the slit-shaped opening 22a are arranged so as to be shifted by a half pitch in the Y-axis direction. The distance (distance between slit edges) between the slit-like opening 12a (branch part br ₁ , branch part br ₂ ) and the slit-like opening part 22a (branch part br ₁ , branch part br ₂ ) adjacent to each other is 30 μm (45 (° -225 ° direction or 135 ° -315 ° direction). Branches of the slit opening 12a and the slit opening 22a br _3, a slit-shaped opening 22a of the respective opposing electrodes 22 and 12 overlap the bent portion of 12a.

When a voltage is applied between the electrodes 12 and 22, regions R _{1 to} R _{4 in} which the orientation directions of the liquid crystal molecules are different from each other are formed by an oblique electric field generated around the slit-shaped openings 12a and 22a. The regions R _{1 to} R ₄ are regions that are regularly arranged, for example, having the same area.

  In the liquid crystal display device according to the example, the absorption axis direction of the front side polarizing plate 41 is 0 ° -180 ° direction, and the absorption axis direction of the back side polarizing plate 42 is 90 ° -270 ° direction.

  The liquid crystal display element according to the embodiment is, for example, a monochrome display type normally black multi-domain (4-domain) liquid crystal display element that performs bright display when a voltage is applied.

  The liquid crystal display element according to the embodiment is manufactured as follows, for example.

A blue plate glass substrate (outer dimension: 300 mm × 200 mm × 0.7 t) is prepared by applying polishing processing and SiO ₂ undercoat on one surface and forming an ITO film with a thickness of about 400 mm by sputtering or the like. After wet cleaning with an alkaline chemical solution or the like and dry cleaning with a low pressure UV lamp, a photoresist PMER manufactured by Tokyo Ohka Kogyo Co., Ltd. is applied to the entire surface of the ITO film with a roll coater and pre-baked at 110 ° C. for about 10 minutes. Using a photomask designed to display a desired pattern or character, the pattern is transferred onto the photoresist by exposing it to high-pressure mercury lamp light, and then the photoresist is developed with a 0.7 wt% KOH aqueous solution. . Etching of the ITO film with a mixed chemical solution of ferric chloride and hydrochloric acid with a weight ratio of 2: 1 and stripping of the photoresist with an aqueous solution of 2.9 wt% NaOH, which are patterned to form slit-like openings 12a and 22a The glass substrates 11 and 21 with the electrodes 12 and 22 are obtained.

  The glass substrates 11 and 21 with the ITO electrodes 12 and 22 are wet cleaned with an alkaline chemical solution or the like. After the substrates 11 and 21 are dried, they are dry-cleaned by an atmospheric pressure plasma cleaning device, and a vertical alignment film SE4811 manufactured by Nissan Chemical is applied only at a position according to the flexographic plate pattern using a flexographic printing machine. After preliminary baking at 90 ° C. for 15 minutes in a clean oven, main baking is performed at 180 ° C. for 30 minutes to obtain the vertical alignment films 13 and 23. The vertical alignment films 13 and 23 are not subjected to an alignment process such as a rubbing process. Thus, the front side and back side substrates 10 and 20 are manufactured.

If necessary, an insulating film may be formed on one or both of the electrodes 12 and 22 before applying the alignment film material. The insulating film can be obtained by, for example, forming a SiO ₂ film by sputtering or applying an organosilane insulating film by flexographic printing, and then irradiating with high-pressure mercury lamp light and baking at 270 ° C. for 30 minutes.

  After the spacers 31 are uniformly distributed on the surfaces of one of the substrates 10 and 20, and the sealing material mixed with the spacer is printed on the other substrates 20 and 10, the surfaces of the electrodes 12 and 22 of both the substrates 10 and 20 face each other. Paste together. At this time, alignment is performed so that the positions of the slit-like openings 12a and 22a on both the electrodes 12 and 22 are appropriate.

  Specifically, a heat firing curable sealing material HC1920 manufactured by Mitsui Chemicals Co., Ltd., in which about 2 wt% of a lot glass fiber spacer made by Nippon Electric Glass is added on one of the substrates 10 and 20, is placed at a desired position by a dispenser device. Apply and pre-fire at 90 ° C. for 5 minutes in a clean oven. In manufacturing the liquid crystal display element according to the example, the size of one liquid crystal cell was set to 35 mm × 25 mm (including an external extraction terminal portion), and 56 planes were taken in a 300 mm × 200 mm plane.

  For example, Japanese Patent Application Laid-Open No. 2002-148635 shows a spacer (a spacer having a particle diameter of 4 μm manufactured by ibonding) formed of synthetic resin fine particles on the other substrates 20 and 10 and not subjected to any surface treatment by surface coating or the like. The substrate 20 and the surface of the substrate 10 are uniformly distributed by a dry fine particle spraying method, and the substrate is baked at 120 ° C. for 10 minutes in a clean oven.

  The electrodes 12 and 22 of the one substrate 10 and the other substrate 20 are opposed to each other, the two substrates 10 and 20 are aligned so as to obtain a desired display pattern, and then both the substrates 10 and 20 are pressed with a uniform pressure. . The sealing material is cured by baking at 150 ° C. for 1 hour or longer with the gap between the substrates 10 and 20 close to the spacer diameter.

  After splitting the multi-faced empty cell in a scribing and breaking process, no chiral material is added, dielectric anisotropy is negative, refractive index anisotropy (birefringence index) Δn is about 0.08 A nematic liquid crystal material manufactured by Merck Co., Ltd. is injected by a vacuum injection method. An ultraviolet curable resin manufactured by ThreeBond Co., Ltd. is applied to the inlet, and the resin is infiltrated slightly inward from the inlet, and then cured and sealed with high-pressure mercury lamp light. The sealed cell is annealed in a clean oven at 120 ° C. for 60 minutes, and after chamfering and polishing the external extraction terminal of the liquid crystal cell, it is washed with a neutral detergent or the like. After drying, the polarizing plates 41 and 42 are bonded to both surfaces of the liquid crystal cell so as to be crossed Nicols, thereby completing the liquid crystal display element. A clip pin or the like is attached to the external lead-out terminal and connected to an external drive device (drive circuit 43) so that the light / dark state of a desired area can be switched.

  FIG. 3C is a microscope observation image (alignment texture image) when a voltage is applied to the liquid crystal display element according to the example.

As is apparent from the figure, in the liquid crystal display device according to an embodiment, the strip dark region D ₂ shown in FIG. 1 are not permitted.

The liquid crystal display device according to the embodiment, the liquid crystal molecules (so as to be parallel to the surface) is horizontally despite using the spacer oriented, for example generation of a dark region D ₂ is suppressed, display uniformity It can be seen that this is a liquid crystal display element with high. The liquid crystal display element according to the embodiment is a liquid crystal display element having high display quality that can be manufactured at low cost and a short tact time, and is multiplex driven by an optimum bias drive that can obtain the best contrast, for example.

The inventor of the present application manufactured many liquid crystal display elements in addition to the liquid crystal display elements according to the examples, and conducted earnest research on suppression of the dark region D _{2 and the} like and improvement of display quality.

  4A to 4H are schematic plan views showing examples of electrode patterns (opening pattern) of the manufactured liquid crystal display element.

Shown in FIG. 4A is an example of electrodes 12 and 22 with a slit opening 12a, 22a of the zigzag excluding the branch br ₃ from the opening pattern in the embodiment.

  That is, in the example shown in FIG. 4A, the slit-shaped openings 12a and 22a have the same shape, and each slit-shaped opening 12a and 22a extends in the X-axis direction as a whole.

The slit-shaped openings 12a and 22a are configured by branch parts (rectangular openings) br ₁ and br _{2 having} a width of 10 μm that are regularly arranged. The branch part br ₁ extends in the direction of 135 ° to 315 ° and has a length of about 150 μm. The branch part br ₂ extends in the direction of 45 ° to 225 ° and has a length of about 150 μm. Branches br ₁ and branch br ₂ is coupled alternately to each other in the end.

In the front transparent electrode 12, a plurality of slit-shaped openings 12a are regularly arranged at regular intervals so that the positions of the bent portions are aligned along the Y-axis direction. Specifically, when viewed along the Y-axis direction, they are arranged at a constant period with a distance of about 100 μm between the branch parts br ₁ or between the branch parts br ₂ .

  The slit-shaped opening 22 a is arranged on the back side transparent electrode 22 in the same manner as the slit-shaped opening 12 a in the front-side transparent electrode 12.

When viewed from the Z-axis direction, the slit-shaped openings 12a and the slit-shaped openings 22a are alternately arranged along the Y-axis direction so as to be shifted by a half pitch in the Y-axis direction. The bent portion of the slit-like opening 12a and the bent portion of the slit-like opening 22a are aligned along the Y-axis direction. The distance between the bent portion of the slit-shaped opening 12a adjacent to the Y-axis direction and the bent portion of the slit-shaped opening 22a is constant (about 42 μm). The distance (distance between slit edges) between the slit-like opening 12a (branch part br ₁ , branch part br ₂ ) and the slit-like opening part 22a (branch part br ₁ , branch part br ₂ ) adjacent to each other is 30 μm. .

When a voltage is applied between the electrodes 12 and 22, regions R _{1 to} R _{4 in} which the orientation directions of the liquid crystal molecules are different from each other are formed by an oblique electric field generated around the slit-shaped openings 12a and 22a. The regions R _{1 to} R ₄ are regions that are regularly arranged, for example, having the same area.

Refer to FIG. 4B. FIG. 4A shows slit-like openings 12a and 22a in which the branch part br ₁ and the branch part br ₂ are alternately joined at the ends thereof, but FIG. 4B shows a single branch part br ₁ and V-shaped slit opening 12a in which one branch br ₂ are attached with each other end is 22a.

The branch part br ₁ is a rectangular opening having a length of about 150 μm and a width of 10 μm extending in the direction of 135 ° to 315 °. The branch part br ₂ is a rectangular opening having a length of about 150 μm and a width of 10 μm extending in the 45 ° -225 ° direction. The branch portions br ₁ and br ₂ are arranged such that the 90 ° direction is a V-shaped convex direction.

  In the front transparent electrode 12, slit-shaped openings 12a are regularly and periodically arranged at a constant pitch in the X-axis direction and the Y-axis direction. When viewed along the X-axis direction, the slit-shaped openings 12a are arranged at regular intervals with a distance slightly shorter (for example, several μm) than the length of the slit-shaped openings 12a along the X-axis direction. Further, when viewed along the Y-axis direction, the slit-shaped openings 12a are arranged at regular intervals with a distance of about 100 μm. When viewing two rows of the opening portions 12a adjacent in the X-axis direction, the slit-shaped opening portions 12a are arranged so as to be shifted from each other by a half pitch in the Y-axis direction. That is, on the front transparent electrode 12, the center of gravity of each slit-shaped opening 12a is arranged in a checkered pattern.

  The slit-like opening 22 a of the back side transparent electrode 22 has the same shape as the slit-like opening 12 a of the front side transparent electrode 12. The slit-shaped opening 22 a is arranged on the back side transparent electrode 22 in the same manner as the slit-shaped opening 12 a in the front-side transparent electrode 12.

When viewed from the Z-axis direction, the slit-shaped opening 12a and the slit-shaped opening 22a are arranged so as to be shifted by a half pitch in either the X-axis direction or the Y-axis direction. Therefore, when viewed along the X-axis direction, the slit-shaped openings 12a (branches br ₁ , branches br ₂ ) and the slit-shaped openings 22a (branches br ₂ , branches br ₁ ) are alternately arranged. Placed and overlaps at the end. When viewed along the Y-axis direction, the adjacent slit-like opening 12a (branch part br ₁ , branch part br ₂ ) and slit-like opening part 22a (branch part br ₁ , branch part br ₂ ) are approximately 42 μm. Are arranged at a distance of. That is, the distance between the slit edges of the slit-like opening 12a (branch part br ₁ , branch part br ₂ ) and the slit-like opening part 22a (branch part br ₁ , branch part br ₂ ) adjacent in the Y-axis direction is 30 μm. Become. The zigzag shape extending in the X-axis direction as a whole is arranged at a constant period with a distance of about 42 μm in the Y-axis direction by the slit-shaped opening 12a and the slit-shaped opening 22a.

When a voltage is applied between the electrodes 12 and 22, regions R _{1 to} R _{4 in} which the orientation directions of the liquid crystal molecules are different from each other are formed by an oblique electric field generated around the slit-shaped openings 12a and 22a. The regions R _{1 to} R ₄ are regions that are regularly arranged, for example, having the same area.

Reference is made to FIG. 4C. 4A and 4B show the slit-like openings 12a and 22a where the branch part br ₁ and the branch part br ₂ are joined to each other, but FIG. 4C shows a branch shape (rectangular shape). In this example, the opening br ₁ and the branch (rectangular) opening br ₂ are arranged without being coupled by the electrodes 12 and 22.

The slit-shaped opening 12a is composed of two types of branch-shaped openings br ₁ and br ₂ . The branch opening br ₁ is an opening having a length of about 150 μm and a width of 10 μm extending in a 135 ° -315 ° direction, and the branch opening br ₂ is a length of about 150 μm extending in a 45 ° -225 ° direction, The opening has a width of 10 μm.

In the front transparent electrode 12, both the branch openings br ₁ and br ₂ are regularly and periodically in the X-axis direction and the Y-axis direction, specifically, in the X-axis direction and the Y-axis direction, respectively. Each is arranged at a constant pitch. The arrangement pitch of the branch openings br ₁ and br ₂ is the same.

When viewed along the X-axis direction, a row in which only the branch opening br ₁ is arranged and a row in which only the branch opening br ₂ is arranged alternately appear. Further, when viewed along the Y-axis direction, rows in which only the branch opening br ₁ is arranged and rows in which only the branch opening br ₂ is arranged alternately appear. That is, the centers of gravity of the branch openings br ₁ and br ₂ are arranged in a checkered pattern.

When viewed along the X-axis direction, the branch openings br ₁ and br ₂ are constant over a distance slightly shorter (for example, several μm) than the length of the branch openings br ₁ and br ₂ along the X-axis direction. Arranged in a cycle. Further, when viewed along the Y-axis direction, the branch openings br ₁ and br ₂ are arranged at a constant period with a distance of about 100 μm.

The slit opening 22a of the back side transparent electrode 22 (branch openings _br 1, br _2), the slit opening 12a (branch openings _br 1, br ₂₎ of the front transparent electrode 12 and the same shape. The slit-shaped openings 22a (branch-shaped openings br ₁ , br ₂ ) are arranged on the back side transparent electrode 22 in the same manner as the slit-shaped openings 12a (branched openings br ₁ , br ₂ ) in the front-side transparent electrode 12. Is done.

When viewed from the Z-axis direction, the slit opening 12a of the front transparent electrode 12 (branch openings _br 1, br ₂₎ a slit-shaped opening 22a of the back side transparent electrode 22 (branch openings _br 1, _br 2) Are arranged so as to be shifted by a half pitch in the Y-axis direction. Therefore, the slit-shaped openings 12a (branched openings br ₁ and branch-shaped openings br ₂ ) and the slit-shaped openings 22a (branched openings br ₂ and branch-shaped openings) that are adjacent to each other along the X-axis direction. The portion br ₁ ) overlaps at the end. Also, slit-like openings 12a (branch openings br ₁ , branch-like openings br ₂ ) and slit-like openings 22a (branch openings br ₁ , branch-like openings) adjacent to each other along the Y-axis direction. The distance between the slit edges of br ₂ ) is 30 μm. A zigzag shape extending in the X-axis direction as a whole by the slit-shaped opening 12a and the slit-shaped opening 22a is arranged at a constant period with a distance of about 42 μm in the Y-axis direction.

In the example shown in FIG. 4C, the line and the branch opening br ₁ of branch openings br ₂ and the electrode 22 of the electrode 12 is coupled at the end alternately branch opening of the electrode 12 br ₁ and the branch opening portions br _{2 of the} electrodes 22 alternately appear at the end portions alternately appear in the Y-axis direction. Further, the columns and the branch opening br ₁ of branch openings br ₁ and the electrode 22 of the electrode 12 are alternately arranged, the branch opening br ₂ of branch openings br ₂ and the electrode 22 of the electrode 12 Are alternately arranged in the X-axis direction.

When a voltage is applied between the electrodes 12 and 22, regions R _{1 to} R _{4 in} which the orientation directions of the liquid crystal molecules are different from each other are formed by an oblique electric field generated around the slit-shaped openings 12a and 22a. The regions R _{1 to} R ₄ are regions that are regularly arranged, for example, having the same area.

  3B and FIGS. 4A to 4C show the slit-shaped opening 12a when the slit-shaped openings 12a and 22a of the electrodes 12 and 22 of the substrates 10 and 20 are viewed from the normal direction of the substrate 10 and 20. 22a, a multi-domain (4-domain) liquid crystal display element that forms a zigzag slit-like opening extending in the X-axis direction as a whole. The zigzag slit-shaped openings formed as a whole are arranged at equal intervals along the Y-axis direction, specifically, so that the distance between slit edges (domain width) is 30 μm.

  Reference is made to FIGS. 4D to 4F. 4D to 4F show an example in which the display region is divided into a plurality of small regions (subpixels) in which liquid crystal molecules are radially aligned. In each figure, one of the small areas is indicated by hatching. The small region has, for example, a square shape having two sides in the X-axis direction and the Y-axis direction. In each example, the plurality of small regions have the same shape and are disposed adjacent to each other in the X-axis direction and the Y-axis direction.

  The example shown in FIG. 4D will be described. In the example shown in FIG. 4D, the small region has a square shape of 60 μm × 60 μm when viewed from the normal direction of the substrates 10 and 20.

  The opening 12a of the front transparent electrode 12 is a circular opening of 10 μmφ. In the X-axis direction and the Y-axis direction, they are arranged in a lattice pattern at a constant pitch (distance between centroids is 60 μm).

The slit-shaped opening 22a of the back side transparent electrode 22 is composed of two types of branch-shaped openings br ₁ and br ₂ . The branch opening br ₁ is a rectangular opening having a length of 70 μm and a width of 10 μm extending in the X-axis direction, and the branch opening br ₂ is a rectangular opening having a length of 70 μm and a width of 10 μm extending in the Y-axis direction. Part.

The branch openings br ₁ are regularly and periodically arranged in the X-axis direction and the Y-axis direction at a constant pitch (the distance between the centers of gravity is 120 μm for both). When viewing two rows adjacent in the X-axis direction, the branch openings br ₁ are arranged so as to be shifted from each other by a half pitch in the Y-axis direction. That on the back side transparent electrode 22, the center of gravity of each branch openings br ₁ is arranged in a checkerboard pattern.

The branch openings br ₂ are also arranged regularly and periodically in the X-axis direction and the Y-axis direction at a constant pitch (the distance between the centers of gravity is 120 μm for both). When viewing two columns adjacent in the X-axis direction, the branch openings br ₂ are arranged so as to be shifted from each other by a half pitch in the Y-axis direction. That on the back side transparent electrode 22, the center of gravity of each branch openings br ₂ are also arranged in a checkerboard pattern.

Branch opening br _1, br ₂ is the center of gravity of the branch opening br ₂ is to the center of gravity of the branch opening br _1, X-axis direction, arranged to be shifted by half a pitch in one of the Y-axis direction Is done. Therefore, the slit-shaped openings 22a are arranged in a lattice pattern at a constant pitch (the distance between the centers of gravity is 60 μm, that is, the same pitch as the circular openings 12a) in each of the X-axis direction and the Y-axis direction, and the X-axis For both the direction and the Y-axis direction, the branch openings br ₁ and the branch openings br ₂ are alternately arranged.

  When viewed from the normal direction of the substrates 10 and 20, the circular opening 12a and the slit-shaped opening 22a are arranged so as to be shifted by a half pitch in both the X-axis direction and the Y-axis direction.

Each of the 60 μm × 60 μm square small regions described above, when viewed from the normal direction of the substrates 10 and 20, is an imaginary straight line extending in the X-axis direction through the center in the width direction of the branch opening br ₁ ; It is defined by a virtual straight line extending in the Y-axis direction through the center in the width direction of the branch opening br ₂ . In each square-shaped small region, a contour (four sides) is formed by a part of four branch openings br ₁ and br ₂ adjacent to each other in the X-axis direction and the Y-axis direction and the electrode 22 part on the extension line. Is done. For example, in the small area hatched in FIG. 4D, when viewed in the counterclockwise direction, first, the openings br ₁ and br ₂ appear, and then the electrode 22 appears.

  In each small region, the adjacent small region and the electrode 22 are connected on one side across the corner (vertex portion) of the square. The opposite side includes the electrode 22 portion only in one diagonal direction.

A circular opening 12a is arranged at the center of each small region. Since the diameter of the circular opening 12a is 10 μm, it is between the edge of the circular opening 12a and the edges (slit edges) of the branch-shaped openings br ₁ and br ₂ arranged on the four sides of the small square region. The distance is 20 μm.

  When a voltage is applied between the electrodes 12 and 22, in each of the small regions, liquid crystal molecules are radiated (360 ° in all directions) around the opening 12a by an oblique electric field generated around the openings 12a and 22a. An oriented multi-domain alignment state is realized.

  Reference is made to FIG. 4E. In the example shown in FIG. 4E, the small region has a square shape of 90 μm × 90 μm when viewed from the normal direction of the substrates 10 and 20.

  The opening 12a of the front transparent electrode 12 is a circular opening of 10 μmφ. In the X-axis direction and the Y-axis direction, they are arranged in a grid pattern at a constant pitch (distance between centroids is 90 μm).

The opening 22a of the back side transparent electrode 22 is T-shaped. X-axis extending length 150 [mu] m, and branch (rectangular) opening br ₁ of width 10 [mu] m, Y axis direction extending length 160 .mu.m, width 10 [mu] m like branches (like a rectangle) is constituted by an opening br ₂ The The center of one edge in the length direction of the opening portion br ₁ and the end portion in the length direction of the opening portion br ₂ are combined.

  The T-shaped openings 22a are arranged regularly and periodically in the X-axis direction and the Y-axis direction at a constant pitch (both distances between the centers of gravity are 180 μm). When viewing the two rows of the opening portions 22a adjacent to each other in the X-axis direction, the opening portions 22a are arranged so as to be shifted from each other by a half pitch in the Y-axis direction. That is, on the back side transparent electrode 22, the center of gravity of each opening 22a is arranged in a checkered pattern.

Each of the 90 μm × 90 μm square small regions described above, when viewed from the normal direction of the substrates 10 and 20, is an imaginary straight line extending in the X-axis direction through the center in the width direction of the branch opening br ₁ . It is defined by a virtual straight line extending in the Y-axis direction through the center in the width direction of the branch opening br ₂ . In each square-shaped small region, a contour (four sides) is formed by a part of the T-shaped opening 22a (branch opening br ₁ , br ₂ ) and the electrode 22 portion on the extension line.

In the small square region, for example, the branch-shaped opening portions br ₁ and br ₂ coupling portions of the T-shaped opening portion 22a (first T-shaped opening portion) are set as one corner portion (vertex portion). There is no electrode 22 portion on one side (first side) formed by the branch opening br ₂ extending from the corner. That is, a side is constituted by only a part of the branch opening br ₂ . The other side (second side) sandwiching the corner portion is configured to include a part of the branch opening br ₁ and the electrode 22 part on the extension line.

The opposite side (third side) of the first side is one of the branch-shaped openings br ₂ of the T-shaped openings 22a (second T-shaped openings) of the adjacent rows on the X-axis negative direction side. Part and the electrode 22 part on the extension line. Also, the opposite side (fourth side) of the second side is the T-shaped opening 22a (third T-shaped opening) adjacent to the second T-shaped opening 22a on the Y-axis negative direction side. some of the branch opening br ₁ of), and configured to include an electrode 22 portion of its extension.

  In the example shown in FIG. 4E, the adjacent small region and the electrode 22 are connected to each other at one side of the three corners of the square small region. In the remaining corner (the corner formed by sandwiching the first side and the second side), the electrode 22 is divided by the adjacent small region electrode 22 and the opening 22a.

A circular opening 12a is arranged at the center of each small region. Since the diameter of the circular opening 12a is 10 μm, it is between the edge of the circular opening 12a and the edges (slit edges) of the branch-shaped openings br ₁ and br ₂ arranged on the four sides of the small square region. The distance is 35 μm.

  When a voltage is applied between the electrodes 12 and 22, in each of the small regions, liquid crystal molecules are radiated (360 ° in all directions) around the opening 12a by an oblique electric field generated around the openings 12a and 22a. An oriented multi-domain alignment state is realized.

Reference is made to FIG. 4F. In the example shown in FIG. 4F, the small region has a square shape of 90 μm × 90 μm when viewed from the normal direction of the substrates 10 and 20. When viewed from the normal direction of the substrates 10 and 20, the square-shaped small region in FIG. 4D is such that all of the four sides are part of the opening 22a (branched openings br ₁ and br ₂ ) and its extension line. Electrode 22 part. The square small region in FIG. 4E is configured so that three sides include a part of the branch-shaped openings br ₁ and br ₂ and the electrode 22 part on the extension line, and one side has the branch-shaped opening br _2. It consists of only a part of. In the example of FIG. 4F, two sides are configured to include a part of the branch opening br ₁ and the electrode 22 part on the extension line, and two sides are only a part of the branch opening br _2. A square-shaped small region constituted by a part of the opening 22a (branch-shaped openings br ₁ , br ₂ ) on all four sides and an electrode 22 portion on the extension line is formed. appear.

  The opening 12a of the front transparent electrode 12 in FIG. 4F is a 10 μmφ circular opening. In the X-axis direction and the Y-axis direction, they are arranged in a grid pattern at a constant pitch (distance between centroids is 90 μm).

  Each opening 22a of the back side transparent electrode 22 shown to FIG. 4F is the same T shape as the opening 22a of FIG. 4E. It is the same in that the openings 22a are regularly and periodically arranged in the X-axis direction and the Y-axis direction at a constant pitch (the distance between the centers of gravity is 180 μm). In the example shown in FIG. 4E, the T-shaped openings 22a are arranged so as to be shifted by a half pitch from each other in the Y-axis direction when the two openings 22a adjacent to each other in the X-axis direction are viewed. On the other hand, in the example shown in FIG. 4F, when viewing the two openings 22a adjacent to each other in the X-axis direction, the T-shaped openings 22a are opposite to each other in units of rows (mutually along the Y-axis. In the Y-axis direction so as to be shifted by a predetermined pitch.

Each of the 90 μm × 90 μm square small regions described above, when viewed from the normal direction of the substrates 10 and 20, is an imaginary straight line extending in the X-axis direction through the center in the width direction of the branch opening br ₁ . It is defined by a virtual straight line extending in the Y-axis direction through the center in the width direction of the branch opening br ₂ .

For example, with respect to a small area with diagonal lines, when viewed from the normal direction of the substrates 10 and 20, two T-shaped openings 22a (branch openings br ₁ and br ₂ ) adjacent in the X-axis direction, A contour (four sides) is formed by the electrode 22 portion on the extension line.

The hatched square-shaped small area has one corner portion (first corner portion) of the branch-like opening portions br ₁ and br ₂ of the T-shape opening portion 22a (first T-shape opening portion). And There is no electrode 22 portion on one side (first side) formed by the branch-shaped opening br ₂ extending from the first corner. That is, a side is constituted by only a part of the branch opening br ₂ . Another side (second side) sandwiching the first corner is configured to include a part of the branch opening br ₁ and the electrode 22 part on the extension line.

Further, the hatched square-shaped small area is a branch-shaped opening br _{1 of} the T-shaped opening 22a (second T-shaped opening) adjacent to the first T-shaped opening in the X-axis direction. , Br ₂ coupling portion is defined as one corner (second corner). The first corner and the second corner are opposite corners. There is no electrode 22 portion on one side (third side) formed by the branch opening br ₂ extending from the second corner. That is, it is a side constituted by only a part of the branch opening br ₂ . Another side (fourth side) sandwiching the second corner is configured to include a part of the branch opening br ₁ and the electrode 22 part on the extension line.

The hatched square small region and the square small region adjacent in the Y-axis direction have different structures, and are adjacent in the X-axis direction and the Y-axis direction when viewed from the normal direction of the substrates 10 and 20. A contour (four sides) is formed by a part of the four T-shaped openings 22a (branch openings br ₁ , br ₂ ) and the electrode 22 on the extension line. All four sides are square-shaped small regions formed by a part of the opening 22a (branch opening br ₁ , br ₂ ) and the electrode 22 part on the extension line.

  Therefore, in the example shown in FIG. 4F, in two opposing corners (first corner and second corner) of the square small region, the electrode 22 is connected to the adjacent small region electrode 22 and the opening. 22a. In the other two opposing corners, a square small region (small region with hatching) in which the adjacent small region and the electrode 22 are connected to each other on one side across the corner. A square-shaped small structure having a structure in which the adjacent small region and the electrode 22 are connected to each other on the side where the corners of the square are sandwiched and the electrode 22 is connected to the opposite side and the electrode 22 portion is provided only in one diagonal direction. Rows in which only the regions (the hatched small region and the square small region adjacent in the Y-axis direction) appear alternately appear in the Y-axis direction.

A circular opening 12a is arranged at the center of each small region. Since the diameter of the circular opening 12a is 10 μm, it is between the edge of the circular opening 12a and the edges (slit edges) of the branch-shaped openings br ₁ and br ₂ arranged on the four sides of the small square region. The distance is 35 μm.

  When a voltage is applied between the electrodes 12 and 22, in each of the small regions, liquid crystal molecules are radiated (360 ° in all directions) around the opening 12a by an oblique electric field generated around the openings 12a and 22a. An oriented multi-domain alignment state is realized.

  Reference is made to FIG. 4G. FIG. 4G shows an example in which the front transparent electrode 12 does not have an opening. Also in the example shown in FIG. 4G, the display area is divided into a plurality of small areas (sub-pixels). The small region has, for example, a square shape having two sides in the X-axis direction and the Y-axis direction. Each small region has the same shape as each other, and is arranged adjacent to the X-axis direction and the Y-axis direction. Also in this figure, one of the small areas is indicated by hatching. The small region in FIG. 4G has a square shape of 60 μm × 60 μm when viewed from the normal direction of the substrates 10 and 20.

In the transparent electrode 22 on the back side of FIG. 4G, openings 22a are formed in a lattice shape in the X-axis direction and the Y-axis direction at a constant pitch (the distance between the centers of gravity is 60 μm). The opening 22a is an L-shaped opening having a length of 50 μm in the X-axis direction and the Y-axis direction. The width of the L-shaped opening 22a is 10 μm. Of the L-shaped opening 22a, a portion extending in the X-axis direction (length 50 μm) is a branch-like (rectangular) opening br ₁ , and a portion extending in the Y-axis direction (length 40 μm) is branch-like (rectangular) and opening br _2.

Each of the 60 μm × 60 μm square small regions described above, when viewed from the normal direction of the substrates 10 and 20, is an imaginary straight line extending in the X-axis direction through the center in the width direction of the branch opening br ₁ ; It is defined by a virtual straight line extending in the Y-axis direction through the center in the width direction of the branch opening br ₂ . In each square small region, an L-shaped opening 22a (branch opening br ₁ , branch opening br ₂ ) and an electrode 22 portion on the extension line form a contour (four sides). The corners of the four (2 rows and 2 columns) L-shaped openings 22a adjacent to each other in the X-axis direction and the Y-axis direction become the four corners of the small square region.

  In the example shown in FIG. 4G, the adjacent small region and the electrode 22 are connected at three corners of the square small region, and the electrode 22 is connected to the adjacent small region electrode 22 and the opening at one corner. It is divided by 22a.

  When viewing the openings 22a constituting each side of the square-shaped small region, the distance between the slit edges of the opening 22a constituting the opposite side is 50 μm.

  When a voltage is applied between the electrodes 12 and 22, the liquid crystal is directed toward the inside of the slit-shaped openings arranged on the four sides in each small square region due to an oblique electric field generated around the openings 12a and 22a. A multi-domain alignment state in which molecules are aligned in a 360 ° azimuth is realized.

  Refer to FIG. 4H. In the example shown in FIG. 4H, the slit-shaped opening 12a formed in the front transparent electrode 12 has a rectangular shape (length 100 μm, width 10 μm) that is long in the Y-axis direction. The slit-shaped openings 12a are regularly and periodically in each of the X-axis direction and the Y-axis direction, specifically, at a constant pitch in the X-axis direction and the Y-axis direction (90 μm in the X-axis direction). They are arranged in a grid pattern on the front transparent electrode 12 (with a distance of 7 μm in the Y-axis direction).

  The slit-like opening 22 a of the back side transparent electrode 22 has the same shape as the slit-like opening 12 a of the front side transparent electrode 12. The slit-shaped opening 22 a is arranged on the back side transparent electrode 22 in the same manner as the slit-shaped opening 12 a in the front-side transparent electrode 12.

  When viewed from the Z-axis direction, the slit-shaped openings 12a of the front transparent electrode 12 and the slit-shaped openings 22a of the back transparent electrode 22 are alternately arranged so as to be shifted by a half pitch in the X-axis direction. For this reason, the distance between the slit edges of the slit-shaped opening 12a and the slit-shaped opening 22a adjacent to each other along the X-axis direction is 40 μm.

When a voltage is applied between the electrodes 12 and 22, regions R ₁ and R _{2 in} which the orientation directions of the liquid crystal molecules are different from each other by 180 ° are formed by an oblique electric field generated around the slit-shaped openings 12a and 22a. The regions R ₁ and R ₂ are regions that are regularly arranged, for example, having the same area. A multi-domain (two-domain) liquid crystal display element is realized by the structure of the electrodes 12 and 22 having the slit-shaped openings 12a and 22a shown in FIG. 4H.

  FIG. 5 is a table showing the appearance observation results for the display of the vertical alignment type liquid crystal display element having the electrode structure shown in FIGS. 4A to 4H. For the liquid crystal display element, a spherical spacer (3DS manufactured by Hayakawa Rubber Co., Ltd.) formed of synthetic resin fine particles and not subjected to surface treatment by surface coating or the like was used, and the display was evaluated for each diameter of the spherical spacer. In this table, a circle indicates a good display with almost no band-like dark area, etc., a triangle indicates a display with slight display unevenness due to the band-like dark area, etc., and a cross indicates a display unevenness due to the band-like dark area. Indicates that this is clearly recognized.

  In addition, the liquid crystal display element used for external appearance observation is the liquid crystal according to the embodiment except that 3DS manufactured by Hayakawa Rubber Co., Ltd. having a diameter of 2.5 μm to 6.0 μm is used as a spherical spacer and patterning of the electrodes 12 and 22. It was manufactured by the same method as the display element. The spherical spacers were sprayed at a uniform spray density of about 100 pieces / mmφ within the display surface. On the 3DS surface manufactured by Hayakawa Rubber Co., Ltd., the liquid crystal molecules are aligned horizontally (so as to be parallel to the spacer surface).

  A drive device (drive circuit 43) that outputs a drive waveform under the optimum bias drive condition of 1/4 duty and 1/3 bias is connected to the external extraction terminal of the liquid crystal display element so that the drive voltage at the time of bright display is appropriate. The appearance when the display area of the liquid crystal display element was all brightly displayed was observed. On the liquid crystal display element, specific figures and characters including 7-segment display are displayed (segment display).

  Reference is made to the columns of FIGS. In the electrode structure of FIGS. 4A to 4C in which a zigzag-shaped opening extends in the X-axis direction as a whole to realize four-domain alignment, good display is obtained at all spacer diameters of 2.5 μm to 6.0 μm. Is obtained. Due to the commonality of the observation results, an equivalent result will be obtained even if the electrode structure shown in FIG. 3B (Example) is used.

  Reference is made to the columns of FIGS. 4D-4G. In the electrode structures of FIGS. 4D to 4G in which the display region is divided into a plurality of small regions (subpixels) and liquid crystal molecules are oriented in a 360 ° azimuth in each small region when a voltage is applied, the observation results are the same. Do not mean.

  In the structure shown in FIG. 4D, good display was obtained with a spacer diameter of 2.5 μm to 4.0 μm, but when a spacer with a diameter of 6.0 μm was used, clear display unevenness was observed. .

  In the structure shown in FIG. 4E and FIG. 4G, good display was obtained at a spacer diameter of 3.0 μm to 4.0 μm. However, when a spacer having a diameter of 2.5 μm was used, the diameter was slightly 6. Obviously, display unevenness was observed when a 0 μm spacer was used.

  In the electrode structure of FIG. 4F, good display was obtained at all spacer diameters of 2.5 μm to 6.0 μm.

  Refer to the column in FIG. 4H. In the electrode structure of FIG. 4H in which the two-domain orientation is realized when a voltage is applied, a good display was obtained only with a spacer diameter of 3.0 μm, but clearly when spacers with other diameters were used. Display unevenness was observed.

  Thus, the display quality depends on the electrode structure and the spacer diameter (cell thickness).

  Next, the dependency of display quality on spacer scattering density will be described.

  FIG. 6 is a table showing the appearance observation results for the display of the vertical alignment type liquid crystal display device having the electrode structure shown in FIGS. 3B and 4D to 4H. For the liquid crystal display element, the spherical spacers used in the examples (a spacer having a particle diameter of 4 μm manufactured by ibonding) were used, and the display was evaluated for each scattering density (pieces / mmφ) of the spacers. Circle marks, triangle marks, and cross marks in this table indicate evaluations equivalent to those in the table of FIG.

  FIG. 7 shows a microscopic observation image (alignment structure image) when a voltage is applied to the vertical alignment type liquid crystal display element having the electrode structure of FIGS. 3B, 4D, 4G, and 4H.

  Here, the liquid crystal display element used for the appearance observation has the patterning of the electrodes 12 and 22 and the dispersion density of the spherical spacers of 56 / mmφ to 315 / mmφ (56 / mmφ in the embodiment). Except for this point, it was fabricated in the same manner as the liquid crystal display device according to the example. The spherical spacers were dispersed with a uniform distribution density in the display surface. The spray density is a measured value under a microscope. As described above, on the surface of a spacer having a particle diameter of 4 μm manufactured by ibonding, liquid crystal molecules are aligned horizontally (so as to be parallel to the spacer surface).

  As in the case of the evaluation shown in FIG. 5, a driving device (driving circuit 43) that outputs a driving waveform under the optimum bias driving conditions of 1/4 duty and 1/3 bias is connected to the external extraction terminal of the liquid crystal display element. The appearance when the display area of the liquid crystal display element was all brightly displayed with a driving voltage of 5 V was observed.

  Furthermore, for reference, in this table, EX004AC2 manufactured by Sekisui Chemical Co., Ltd. (spherical spacer with a particle size of about 4 μm) is used at a spraying density of 214 / mmφ, and 3DS-XD manufactured by Hayakawa Rubber Co., Ltd. The evaluation of the display quality when a spherical spacer having a particle diameter of 4 μm is used at a spraying density of 76 / mmφ is also given. These two types of spherical spacers are spacers in which surface treatment (formation of a coating layer) for vertical alignment is performed on the surface of a synthetic resin. That is, the liquid crystal molecules are aligned perpendicular to the spacer surface.

When manufacturing these liquid crystal display elements, after spraying spacers and firing the substrate at 120 ° C., before pressing the substrate, a 0.6 kgf / cm ² N ₂ blow was separated from the substrate surface by about 15 cm. When applied from the position, a large difference was observed in the number of spacers (spreading density) per unit area before and after N ₂ blow for spacers having a particle diameter of 4 μm manufactured by ibonding. On the other hand, the difference was slight between EX004AC2 manufactured by Sekisui Chemical Co., Ltd. and 3DS-XD manufactured by Hayakawa Rubber Co., Ltd. For this reason, when EX004AC2 manufactured by Sekisui Chemical Co., Ltd. and 3DS-XD manufactured by Hayakawa Rubber Co., Ltd. are used, the coating layer on the spacer surface (modified layer for vertical alignment) is obtained by firing the substrate. It is considered that a part of the spacer was dissolved and the spacer was fixed to the substrate surface. On the other hand, it can be seen that the spacer having a particle diameter of 4 μm manufactured by ibonding Co., Ltd. does not have a coating layer on the surface, and is not easily fixed to the substrate surface.

  Referring to FIG. 6, when the spacer described as a reference (spacer subjected to surface treatment for vertical alignment) is used, good display can be obtained with all the electrode structures of FIGS. 3B and 4D to 4H. . However, in a liquid crystal display element using a spacer (ibonding particle diameter 4 μm spacer) in which liquid crystal molecules are aligned horizontally (so as to be parallel to the surface) on the surface, depending on the electrode structure and the in-plane scattering density of the spacer, It can be seen that the display quality is greatly affected.

  Reference is made to the column of FIG. 3B in FIG. In the liquid crystal display element having the electrode structure shown in FIG. 3B, good display was obtained when the spraying density was 56 / mmφ to 191 / mmφ, but there was slight display unevenness when it was 315 / mmφ. Observed.

  Referring to the column of FIG. 3B in FIG. 7, when the spray density is 56 / mmφ to 191 / mmφ, for example, a band-like dark region is not observed or almost not observed, but when it is 315 / mmφ, In addition, it can be seen that many strip-shaped dark regions are observed.

  4A to 4C having the same structure as that shown in FIG. 3B (the electrode structure that realizes a four-domain alignment by extending a zigzag opening as a whole in the X-axis direction). Will be obtained.

  3B and 4A to 4C have a wide spacer diameter (2.5 μm to 6.0 μm) range (see FIG. 5) and a wide spray density (56 / mmφ to 191 / mmφ). ) (See FIG. 6), it can be seen that good display can be obtained. That is, it can be said that the electrode structure has little dependency on the spacer diameter and the dependency on the amount of dispersed spacer.

  Reference is made to the column of FIG. 4D of FIG. In the liquid crystal display element having the electrode structure shown in FIG. 4D, good display was obtained when the spraying density was 56 / mmφ to 191 / mmφ, but there was slight display unevenness when it was 315 / mmφ. Observed.

  Referring to the column of FIG. 4D in FIG. 7, when the spraying density is 315 / mmφ, the point where the cross-shaped dark region intersects is shifted from the center of the small region within each small region (subpixel). However, many are observed. When the number is 56 / mmφ to 191 / mmφ, the deviation of the intersection of the cross-shaped dark region is slight or not observed, and the display is good. Here, the cross-shaped dark region indicates that the liquid crystal molecular orientation orientation in the small region is formed in an orientation parallel or perpendicular to both polarizing plate absorption axes, and the liquid crystal orientation orientation in the small region is continuously changing. Is.

  Reference is made to the column of FIG. 4E in FIG. In the liquid crystal display element having the electrode structure shown in FIG. 4E, good display was obtained when the spraying density was 56 / mmφ to 105 / mmφ, but when the density was 191 / mmφ to 315 / mmφ, Obvious display irregularities were observed.

  Reference is made to the column of FIG. 4F in FIG. In the liquid crystal display element having the electrode structure shown in FIG. 4F, good display was obtained when the spraying density was 56 / mmφ to 191 / mmφ, but when 315 / mmφ, clear display unevenness was obtained. Observed.

  The electrode structure in FIG. 4F also has a wide spacer diameter (2.5 μm to 6.0 μm) range (see FIG. 5) and a wide spray density (56 / mmφ to 191 / mmφ) (see FIG. 6). Thus, it can be said that the electrode structure has a small dependency on the spacer diameter and the dependency on the amount of dispersed spacer, which can provide a good display.

  Reference is made to the column of FIG. 4G in FIG. In the liquid crystal display element having the electrode structure shown in FIG. 4G, good display was obtained when the spraying density was 56 / mmφ to 105 / mmφ, but when 191 / mmφ to 315 / mmφ, A slight display unevenness was observed.

  Referring to the column of FIG. 4G in FIG. 7, when the spray density is 315 / mmφ, a large number of small regions (subpixels) in which the intersections of the cross-shaped dark regions are shifted from the center are observed. It was found that display uniformity during appearance observation can be ensured by reducing this shift.

  Refer to FIG. 4H in FIG. In the liquid crystal display element having the electrode structure shown in FIG. 4H, clear display unevenness was observed at all the spraying densities of 56 / mmφ to 315 / mmφ.

  Reference is made to the column of FIG. 4H in FIG. A band-like dark region was observed around a part of the spacer disposed between the openings 12a and 22a on the surfaces of both electrodes 12 and 22, and it was found that this dark region was recognized as display unevenness in appearance. . The band-like dark region is observed at all the spraying densities (56 / mmφ to 315 / mmφ) of spacers having a particle diameter of 4 μm manufactured by ibonding.

  For example, when compared with the structures shown in FIGS. 3B and 4A to 4C, the structure of FIG. 4H has a relatively wide distance between the slit edges of 40 μm when viewed from the normal direction of the substrates 10 and 20. (The structure shown in FIGS. 3B and 4A to 4C is 30 μm). Therefore, the inventor of the present application separately manufactured and observed an element in which the distance between the slit edges in FIG. 4H was narrowed. However, unlike the electrode structure shown in FIG. 3B and the like, display uniformity was not realized with all the spraying densities of 56 / mmφ to 315 / mmφ.

  For example, the following will be understood from the observation results shown in FIGS. 5 and 6 and the microscope observation image shown in FIG.

  The electrode structure that realizes the two-domain alignment state shown in FIG. 4H has a large dependency on display spacer diameter and spacer scattering amount, and the conditions for obtaining display uniformity are extremely narrow. When a spacer that aligns liquid crystal molecules so as to be parallel to the surface is used, it is considered difficult to realize a good display state under a wide range of conditions.

  3B and FIGS. 4A to 4C, the electrode structure that realizes the four-domain orientation (the electrode structure in which the zigzag-shaped opening extends in the X-axis direction as a whole) has a spacer diameter dependency and a spacer There is little dependence on the spread rate, and there are a wide range of conditions for obtaining display uniformity during bright display. For this reason, even when a spacer that aligns liquid crystal molecules so as to be parallel to the surface is used, a good display state can be realized under a relatively wide range of conditions. Therefore, it can be said that the electrode structure can reduce the cost of the liquid crystal display element and shorten the tact time.

  The display structure shown in FIGS. 4D to 4G is divided into a plurality of small areas (subpixels), and an electrode structure for aligning liquid crystal molecules in each small area in a 360 ° azimuth direction when applying voltage is more than the structure of FIG. 4H. Although a good display state can be realized in a wide range, the range in which a better display state can be realized than the structures of FIGS. 3B and 4A to 4C except for the structure of FIG. 4F is narrow. However, the electrode structures of FIGS. 4D to 4G can also realize a good display state even when a spacer is used in which the liquid crystal molecules are aligned parallel to the surface. It is an electrode structure that can shorten the time.

  Further, when spacers that align liquid crystal molecules so as to be parallel to the surface are dispersed at a dispersion density of 315 pieces / mmφ or more, good display can be obtained with any of the electrode structures of FIGS. 3B and 4A to 4H. I understand that there is no.

  As mentioned above, although this invention was demonstrated along the Example etc., this invention is not restrict | limited to these.

For example, in the example, when viewed from the normal direction of the substrates 10 and 20, the distance between the slit-shaped opening 12a and the slit-shaped opening 22a adjacent to each other (distance between the slit edges) was 30 μm. invention, as is noted problem "to be solved, strip dark region D ₂ is considered the distance between the slit-shaped opening is formed around the spacer in a relatively long position. Therefore, if the distance between the slit edges is 30 μm or less, at least the same effects (suppression of the band-like dark region and high display quality) can be obtained.

  Similarly, in the case of the electrode structures shown in FIGS. 4A to 4C, high display quality can be obtained if the distance between the slit edges is 30 μm or less.

4D, 4E, and 4F, the distance between the edge of the circular opening 12a and the edges (slit edges) of the branch-like openings br ₁ and br ₂ arranged on the four sides of the small region However, high display quality can be obtained if they are 20 μm or less, 35 μm or less, or 35 μm or less, respectively.

  Also in the structure of FIG. 4G, when viewing the openings 22a constituting each side of the small region, high display quality can be obtained if the distance between the slit edges of the openings 22a constituting the opposite side is 50 μm or less.

  In the example shown in FIGS. 4D to 4G, the shape of the small region is a square shape, but can be a wide rectangular shape.

  Furthermore, in the examples shown in FIGS. 4D to 4F, the circular opening 12a is used. However, the opening is not limited to a circular shape as long as it is an opening that radially aligns liquid crystal molecules in a small region. can do.

  The liquid crystal display element according to the embodiment or the like is a liquid crystal display element that realizes high display quality by suppressing, for example, a dark region generated in at least a part around the spacer.

  It will be apparent to those skilled in the art that other various modifications, improvements, combinations, and the like can be made.

  The present invention can be used for vertical alignment liquid crystal display elements and vertical alignment liquid crystal display devices in general. It can be suitably used for in-vehicle displays, display devices, instruments, industrial equipment displays, instruments, and transportation equipment displays, instruments, for example, railway vehicle displays, instruments, and the like.

10, 20 Substrate 11, 21 Transparent substrate 12, 22 Transparent electrode 12a, 22a Opening 13, 23 Vertical alignment film 30 Liquid crystal layer 31 Spacer 41, 42 Polarizer 43 Drive circuit 50 Front side substrate 51 Glass substrate 52 Transparent electrode 52a Slit shape Opening 53 Vertical alignment film 54 Spacer 55 Liquid crystal layer 56 Space A, A ₁ , A ₂ , B, C, D, R _{1 to} R ₄ region D ₁ , D ₂ Dark region br _{1 to} br ₃ branches

Claims (9)

A first substrate comprising a first electrode and a first vertical alignment film formed so as to cover the first electrode and not subjected to alignment treatment;
A second electrode that is disposed opposite and substantially parallel to the first substrate, includes a second electrode, and a second vertical alignment film that is formed so as to cover the second electrode and that has not been subjected to an alignment treatment; A substrate,
A liquid crystal layer disposed between the first substrate and the second substrate;
A spherical spacer that maintains a constant distance between the first substrate and the second substrate and horizontally aligns the liquid crystal molecules of the liquid crystal layer on the surface;
The first electrode and the second electrode include an opening,
When viewed from the normal direction of the first and second substrates, at least one of the opening of the first electrode and the opening of the second electrode, the zigzag shape extends in the first direction as a whole. A plurality of openings are formed, and the distance between the edges of two zigzag openings adjacent to each other in a second direction orthogonal to the first direction is 30 μm or less,
The spherical spacer has a diameter of 2.5 [mu] m to 6.0 [mu] m, and has a density of 56 / mm [phi] to 191 / mm [phi] and is arranged between the first substrate and the second substrate. Liquid crystal display element.   When viewed from the normal direction of the first and second substrates, the opening of the first electrode and the opening of the second electrode both have a zigzag shape that extends in the first direction as a whole. The liquid crystal display element according to claim 1, wherein zigzag bent portions are aligned in the second direction and are alternately arranged along the second direction.   When viewed from the normal direction of the first and second substrates, the opening portion of the first electrode and the opening portion of the second electrode are further protruded from the respective bent portions having a zigzag shape. The branch-shaped opening that extends in parallel with the second direction is provided in the direction, and the branch-shaped opening overlaps a bent portion of a zigzag-shaped opening adjacent to the second direction. Liquid crystal display element. When viewed from the normal direction of the first and second substrates, both the opening of the first electrode and the opening of the second electrode are V-shaped openings in which the second direction is a convex direction. Is an opening that is arranged so that the center of gravity is in a checkered pattern,
The V-shaped opening of the first electrode and the V-shaped opening of the second electrode are alternately arranged in the first direction so as to overlap each other at the end, and the first electrode as a whole is arranged. The liquid crystal display element according to claim 1, wherein a zigzag-shaped opening extending in the direction is formed. The opening of the first electrode and the opening of the second electrode are both a first branch opening extending in the third direction and a second branch opening extending in the fourth direction. Configured with
The first and second branch openings, when viewed along the first direction on the first and second electrodes, and a row in which only the first branch openings are disposed. The columns in which only the second branch openings are disposed alternately appear, and when viewed along the second direction, the rows in which only the first branch openings are disposed, and the second Are formed so that rows in which only the branch openings are arranged alternately appear,
When viewed from the normal direction of the first and second substrates, the first branch opening of the first electrode and the second branch opening of the second electrode alternately end. A zigzag-shaped first opening extending in the first direction as a whole is formed,
The first opening and the zigzag-shaped second opening adjacent in the second direction are the second branch opening of the first electrode and the second opening of the second electrode. The liquid crystal display element according to claim 1, wherein one branch-like opening is alternately overlapped at an end. A first substrate comprising a first electrode and a first vertical alignment film formed so as to cover the first electrode and not subjected to alignment treatment;
A second electrode that is disposed opposite and substantially parallel to the first substrate, includes a second electrode, and a second vertical alignment film that is formed so as to cover the second electrode and that has not been subjected to an alignment treatment; A substrate,
A liquid crystal layer disposed between the first substrate and the second substrate;
A spherical spacer that maintains a constant distance between the first substrate and the second substrate and horizontally aligns the liquid crystal molecules of the liquid crystal layer on the surface;
The first electrode includes a first opening that is long in a first direction and a second opening that is long in a second direction orthogonal to the first direction. The two directions are formed at a constant pitch in the first and second directions so as to be alternately arranged in both directions,
When viewed from the normal direction of the first and second substrates, an imaginary straight line extending in the first direction through the center in the width direction of the first opening, and the second opening An imaginary straight line extending in the second direction through the center in the width direction, each having two sides in the first direction and the second direction, the first direction and the second direction A plurality of rectangular regions arranged adjacent to each other are defined;
In the second electrode, an opening is formed so as to be arranged at the center of each of the plurality of rectangular regions,
Between the edge of the opening of the first electrode, which constitutes a part of the four sides of the rectangular region, and the edge of the opening of the second electrode arranged at the center of the rectangular region The distance is 20 μm or less,
The spherical spacer has a diameter of 2.5 μm to 4.0 μm and a density of 56 / mmφ to 191 / mmφ and is disposed between the first substrate and the second substrate. element. A first substrate comprising a first electrode and a first vertical alignment film formed so as to cover the first electrode and not subjected to alignment treatment;
A second electrode that is disposed opposite and substantially parallel to the first substrate, includes a second electrode, and a second vertical alignment film that is formed so as to cover the second electrode and that has not been subjected to an alignment treatment; A substrate,
A liquid crystal layer disposed between the first substrate and the second substrate;
A spherical spacer that maintains a constant distance between the first substrate and the second substrate and horizontally aligns the liquid crystal molecules of the liquid crystal layer on the surface;
The first electrode includes a first branch opening that is long in a first direction and a second branch opening that is long in a second direction orthogonal to the first direction. A T-shaped opening formed by combining the center of one edge in the length direction of the branch-shaped opening and the end of the second branch-shaped opening in the length direction is the first direction, And, when viewed with respect to two opening rows adjacent to the first direction at a constant pitch in each of the second directions, formed so as to be shifted by a half pitch in the second direction,
When viewed from the normal direction of the first and second substrates, an imaginary straight line extending in the first direction through the center in the width direction of the first branch opening, and the second branch An imaginary straight line extending in the second direction through the center in the width direction of the opening, and each having two sides in the first direction and the second direction, and the first direction A plurality of rectangular regions disposed adjacent to the second direction are defined;
In the second electrode, an opening is formed so as to be disposed at the center of each of the rectangular regions,
The edge of the T-shaped opening of the first electrode constituting a part of the four sides of the rectangular region, and the edge of the opening of the second electrode disposed in the center of the rectangular region; The distance between is 35 μm or less,
The spherical spacer has a diameter of 3.0 μm to 4.0 μm and a density of 56 / mmφ to 105 / mmφ and is disposed between the first substrate and the second substrate. element. A first substrate comprising a first electrode and a first vertical alignment film formed so as to cover the first electrode and not subjected to alignment treatment;
A second electrode that is disposed opposite and substantially parallel to the first substrate, includes a second electrode, and a second vertical alignment film that is formed so as to cover the second electrode and that has not been subjected to an alignment treatment; A substrate,
A liquid crystal layer disposed between the first substrate and the second substrate;
A spherical spacer that maintains a constant distance between the first substrate and the second substrate and horizontally aligns the liquid crystal molecules of the liquid crystal layer on the surface;
The first electrode includes a first branch opening that is long in a first direction and a second branch opening that is long in a second direction orthogonal to the first direction. A T-shaped opening formed by combining the center of one edge in the length direction of the branch-shaped opening and the end of the second branch-shaped opening in the length direction is the first direction, And when looking at two opening rows adjacent to the first direction at a constant pitch in each of the second directions, they are arranged opposite to each other along the second direction in units of rows. And formed so as to be shifted by a predetermined pitch in the second direction,
When viewed from the normal direction of the first and second substrates, an imaginary straight line extending in the first direction through the center in the width direction of the first branch opening, and the second branch An imaginary straight line extending in the second direction through the center in the width direction of the opening, and each having two sides in the first direction and the second direction, and the first direction A plurality of rectangular regions disposed adjacent to the second direction are defined;
In the second electrode, an opening is formed so as to be disposed at the center of each of the rectangular regions,
The edge of the T-shaped opening of the first electrode constituting a part of the four sides of the rectangular region, and the edge of the opening of the second electrode disposed in the center of the rectangular region; The distance between is 35 μm or less,
The spherical spacer has a diameter of 2.5 μm to 6.0 μm, and a liquid crystal display disposed between the first substrate and the second substrate at a density of 56 / mmφ to 191 / mmφ. element. A first substrate comprising a first electrode and a first vertical alignment film formed so as to cover the first electrode and not subjected to alignment treatment;
A second electrode that is disposed opposite and substantially parallel to the first substrate, includes a second electrode, and a second vertical alignment film that is formed so as to cover the second electrode and that has not been subjected to an alignment treatment; A substrate,
A liquid crystal layer disposed between the first substrate and the second substrate;
A spherical spacer that maintains a constant distance between the first substrate and the second substrate and horizontally aligns the liquid crystal molecules of the liquid crystal layer on the surface;
The first electrode includes an L that includes a first branch opening that extends in a first direction and a second branch opening that extends in a second direction orthogonal to the first direction. Character-shaped openings are formed in a lattice pattern at a constant pitch in each of the first direction and the second direction;
When viewed from the normal direction of the first and second substrates, an imaginary straight line extending in the first direction through the center in the width direction of the first branch opening, and the second branch An imaginary straight line extending in the second direction through the center in the width direction of the opening, and each having two sides in the first direction and the second direction, and the first direction A plurality of rectangular regions disposed adjacent to the second direction are defined;
The distance between the edges of the openings that constitute the opposing sides of the rectangular region is 50 μm or less,
The spherical spacer has a diameter of 3.0 μm to 4.0 μm and a density of 56 / mmφ to 105 / mmφ and is disposed between the first substrate and the second substrate. element.