JP2010002449A - Liquid crystal display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce ripple defect by lessening going and coming of domains different in an orientation direction of liquid crystal molecules in connection parts in a lateral electric field type liquid crystal display panel connecting slit-like openings extending in different directions while bending the slit-like openings in the form of a dogleg. <P>SOLUTION: The liquid crystal display panel includes: an upper electrode 130 having a pair of substrates arranged facing each other by sandwiching a liquid crystal layer and having a plurality of the slit-like openings 130a on one of the pair of the substrates; a lower electrode 128 formed on the side of the substrates via the upper electrode 130 and the insulation layer; and an alignment layer formed on the side of the liquid crystal layer. The slit-like opening 130a is bent in the form of the dogleg, and a part in which width of the slit-like opening 130a is widened is formed on a corner part bent in the form of the dogleg. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a horizontal electric field type liquid crystal display panel. More specifically, the present invention relates to a horizontal electric field type liquid crystal display panel having a slit-like opening bent in a “<” shape on one electrode.

Liquid crystal display panels are characterized by their light weight, thinness, and low power consumption compared to CRTs (cathode ray tubes), and are therefore used in many electronic devices for display purposes. The liquid crystal display panel displays an image by changing the direction of liquid crystal molecules aligned in a predetermined direction by an electric field by rubbing the alignment film, thereby changing the amount of light transmitted or reflected.

As a method of applying an electric field to a liquid crystal layer of a liquid crystal display panel, there are a vertical electric field type and a horizontal electric field type. A vertical electric field type liquid crystal display panel applies a substantially vertical electric field to liquid crystal molecules by a pair of electrodes arranged with a liquid crystal layer interposed therebetween. Known examples of the vertical electric field type liquid crystal display panel include a TN (Twisted Nematic) mode, a VA (Vertical Alignment) mode, and an MVA (Multi-domain Vertical Alignment) mode. A horizontal electric field type liquid crystal display panel is provided with a pair of electrodes insulated from each other on one inner surface side of a pair of substrates disposed with a liquid crystal layer interposed therebetween, and a substantially horizontal electric field is applied to liquid crystal molecules. To be applied. This horizontal electric field type liquid crystal display panel has an IP in which a pair of electrodes do not overlap in a plan view.
An S (In-Plane Switching) system and an overlapping FFS (Fringe Field Switching) system are known.

Among these, in the FFS mode liquid crystal display panel, a pair of electrodes composed of an upper electrode and a lower electrode are arranged in different layers through an insulating film, and a slit-like opening is provided in the upper electrode. A substantially horizontal electric field passing therethrough is applied to the liquid crystal layer. The FFS mode liquid crystal display panel is widely used in recent years because it can obtain a wide viewing angle and improve image contrast.

By the way, in a liquid crystal display panel for color display, usually R (red) and G (green)
Three B (blue) sub-pixels are formed side by side, and one pixel (one pixel) is set by combining these three sub-pixels. Since one pixel is generally square, one subpixel is a vertically long rectangle. Therefore, in the FFS mode liquid crystal display panel, an electric field in a desired direction cannot be formed at both ends of the slit-shaped opening formed in the upper electrode. Therefore, as shown in Patent Documents 1 and 2, The extension direction of the slit-shaped opening is set to the vertical direction to reduce the decrease in the aperture ratio.

Further, in the FFS mode liquid crystal display panel, the slit-shaped opening extends so as to be slightly inclined with respect to the rubbing direction so that liquid crystal molecules can rotate in the same direction. In a liquid crystal display panel for color display, the change in color due to the viewing angle can be reduced by multi-domaining in which the inclination angle of the slit-shaped opening is divided into two areas, positive and negative. However, since the electric field in the desired direction cannot be formed at both ends of the slit-shaped opening, if the slit-shaped openings having different extending directions are separated, the number of ends of the slit-shaped opening increases, resulting in a low aperture ratio. Become. Therefore, in the liquid crystal display panel disclosed in Patent Document 1 below, a multi-domain structure having a wide aperture ratio is achieved by making the slit-shaped openings zigzag and connecting the slit-shaped openings extending in different directions. .
JP 2002-014374 A

However, due to the limitations of the resolution of the exposure apparatus, the resolution of the photoresist, and the like, the outer corner side of the portion connecting the slit-like openings extending in different directions is not sharp but rounded. Therefore, on the outer angle side of the portion where slit-like openings extending in different directions are connected, the direction of the electric field is close to perpendicular to the rubbing direction, and a region (domain) where reverse twist is generated easily occurs. On the other hand, when two slit-like openings having different extending directions are formed, domains having different alignment directions of the liquid crystal molecules are formed on the respective slit-like openings, so that there is an advantage that wide viewing angle characteristics can be obtained. However, when two slit-like openings having different extending directions are connected, domains having different orientation directions go back and forth, which causes a problem that a ripple defect occurs.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a horizontal electric field type liquid crystal display panel in which slit-like openings extending in different directions are bent and connected in a "<" shape. The present invention provides a liquid crystal display panel in which a reverse twist domain is less likely to occur and a ripple defect is reduced by reducing the number of domains having different alignment directions of liquid crystal molecules at a connecting portion.

In order to achieve the above object, a liquid crystal display panel according to the present invention has a pair of substrates disposed to face each other with a liquid crystal layer interposed therebetween, and an upper electrode having a plurality of slit-like openings on one of the pair of substrates. And the lower electrode formed on the substrate side through the upper electrode and the insulating layer, and the alignment film formed on the liquid crystal layer side, the slit-like opening is In addition to being bent in a letter shape, a corner having a wider slit-like opening is formed in the corner part bent in the above-mentioned "<" shape.

According to the crystal display panel of the present invention, since the width of the slit-shaped opening of the corner portion folded in the “<” shape is wide, the liquid crystal is formed in the corner portion folded in the “<” shape. Since it is difficult for voltage to be applied to the molecules, the rotation of the liquid crystal molecules is reduced and the reverse twist domain is less likely to occur. Also, as the width of the slit-shaped opening becomes wider, the angle formed by the rubbing direction and the side of the slit-shaped opening changes, so the orientation direction of the liquid crystal molecules on both sides of the corner that is bent in this "<" shape is changed. It becomes difficult for different domains to move back and forth, and ripple defects can be reduced.

Further, the widened portion of the slit-shaped opening is formed by projecting the outer corner side of the corner portion of the previous slit-shaped opening bent in a “<” shape into a wedge shape to the outer angle side. It is preferred that

According to the liquid crystal display panel of this aspect, when the side on the outer corner side of the corner portion bent in a “<” shape is projected in a wedge shape, the edge is not sharp but is rounded as in the conventional example. Since problems can be avoided, the occurrence of reverse twist domains can be reduced. In addition, since the change in the direction of the electric field in a plan view is large on the outer corner side of the corner portion, domains having different orientation directions do not easily go back and forth at the corner portion. In addition, on the outer corner side of the corner portion, the angle formed by the rubbing direction and the electric field direction becomes small and a large rotational force is obtained against the liquid crystal molecules, so that the surface of the liquid crystal display panel is temporarily pressed. Even if a ripple occurs due to a change in the rotation angle of the liquid crystal molecules, it easily returns to the original state.

Further, in the liquid crystal display panel of the present invention, the widened portion of the slit-shaped opening has a wedge-shaped side on the inner corner side of the corner portion of the slit-shaped opening that is bent in a “<” shape. It is preferably formed by protruding toward the inner corner.

According to the liquid crystal display panel of this aspect, the corner portion can also be protruded toward the inner corner side like a wedge by projecting the inner corner side of the corner portion folded in a “<” shape into a wedge shape. Since it is difficult to apply a voltage to the liquid crystal molecules on the inner angle side, the rotation of the liquid crystal molecules becomes small and a reverse twist domain hardly occurs. In addition, since the change in the direction of the electric field in a plan view becomes large on the inner corner side of this corner portion, domains having different orientation directions of liquid crystal molecules on both sides of this corner portion are difficult to go back and forth, thereby reducing ripple defects. can do.

Further, in the liquid crystal display panel of the present invention, the width of the slit-shaped opening is continuously the same as the width of the slit-shaped opening at the corner portion of the slit-shaped opening that is bent in a “<” shape. It is preferable that the inner angle side and the outer angle side are both protruded to the outer angle side so as to be larger.

According to the liquid crystal display panel of this aspect, the angle formed by the rubbing direction and the electric field direction is small on both sides of the corner portion folded in a “<” shape, so that a large rotational force is given to the liquid crystal molecules. When the liquid crystal display panel is temporarily pressed to change the rotation angle of the liquid crystal molecules, the original rotation angle is more easily returned. In addition, since the angle with respect to the rubbing direction is different for both the inner angle side and the outer angle side of this corner, the area with different VT (voltage-transmittance) characteristics increases, so that the color difference due to the viewing angle is reduced. Can be reduced.

In the liquid crystal display panel of the present invention, the widened portion of the slit-shaped opening is formed in a state where the same-width portion of the slit-shaped opening is once bent to the outer angle side, and further, the slit It is preferable that the outer side of the corner portion of the opening that is bent in a “<” shape is protruded in a wedge shape toward the outer side.

According to the liquid crystal display panel of this aspect, the angle formed by the rubbing direction and the electric field direction is small on both sides of the corner portion folded in a “<” shape, so that a large rotational force is given to the liquid crystal molecules. When the liquid crystal display panel is temporarily pressed to change the rotation angle of the liquid crystal molecules, the original rotation angle can be easily returned. In addition, the part where the angle with respect to the side of the slit-shaped opening and the rubbing direction is different is not only the side on the inner corner side and the side on the outer corner side of the corner portion folded in a “<” shape but also the same width of the slit. Since this also occurs in a portion where the portion is bent once, the region having different VT characteristics increases, and the color difference due to the viewing angle can be further reduced.

In the liquid crystal display panel of the present invention, it is preferable that a portion where the width of the slit-shaped opening is wide is communicated with an adjacent slit-shaped opening in the same pixel region.

According to the liquid crystal display panel of this aspect, since the portion where the width of the slit-shaped opening is wide is communicated with the adjacent slit-shaped opening in the same pixel region, it is difficult to apply a voltage to the liquid crystal molecules. , The rotation of the liquid crystal molecules becomes small, and the reverse twist domain hardly occurs.

Hereinafter, the best embodiment of the present invention will be described with reference to the drawings. However, the embodiment described below exemplifies a liquid crystal display panel for embodying the technical idea of the present invention, and is not intended to specify the present invention for this liquid crystal display panel. Other embodiments within the scope of the claims are equally applicable. Furthermore, in each drawing used for the description in this specification, each layer and each member are displayed with different scales so that each layer and each member can be recognized on the drawing. However, it is not necessarily displayed in proportion to the actual dimensions.

FIG. 1 is a front view of one sub-pixel showing a slit-like opening of the liquid crystal display panel according to the first embodiment. FIG. 2 is a sectional view taken along line II-II in FIG. FIG. 3 is a sectional view taken along line III-III in FIG. FIG. 4 is a diagram illustrating a rotation state of liquid crystal molecules in the first embodiment.
FIG. 5 is a diagram showing a rotation state of liquid crystal molecules in a modification of the first embodiment. FIG. 6 shows the second
It is a front view for 1 sub pixel which shows the slit-shaped opening of the liquid crystal display panel which concerns on this embodiment.
FIG. 7 is a front view of one sub-pixel showing a slit-like opening of the liquid crystal display panel according to the third embodiment. FIG. 8 is a diagram showing a rotation state of liquid crystal molecules in the third embodiment. FIG. 9 is a front view of one sub-pixel showing a slit-like opening of the liquid crystal display panel according to the fourth embodiment. FIG. 10 is a diagram illustrating a rotation state of liquid crystal molecules in the fourth embodiment.

[First Embodiment]
The liquid crystal display panel 1 according to the first embodiment will be described with reference to FIGS. As shown in FIGS. 2 and 3, the liquid crystal display panel 1 has a liquid crystal layer 11 sandwiched between an array substrate 12 and a color filter substrate 14. The thickness of the liquid crystal layer 11 is made uniform by the spacer 111. A first polarizing plate 15 is formed on the back surface of the array substrate 12, and a second polarizing plate 16 is formed on the front surface of the color filter substrate 14. Further, a backlight 17 that irradiates light on the back side of the array substrate 12 is disposed.

First, the configuration of the array substrate 12 will be described. The array substrate 12 has a substrate body 121 made of glass, quartz, plastic or the like as a base. A scanning line 122 is formed on the substrate body 121 of the array substrate 12 on the liquid crystal layer 11 side, and a gate insulating film 123 is formed to cover the scanning line 122. A semiconductor layer 124a made of, for example, amorphous silicon is formed on the gate insulating film 123, and a source electrode 124b and a drain electrode 125c are formed so as to partially run over the semiconductor layer 124a. These semiconductor layer 124a, source electrode 124b, and drain electrode 124c constitute a TFT 124. The semiconductor layer 124 a is disposed to face the scanning line 122 with the gate insulating film 123 interposed therebetween, and the scanning line 122 forms the gate electrode 122 a of the TFT 124 in the facing region. The source electrode 124b branches from the data line 125, and the data line 125
1 extends in the Y-axis direction of FIG. 1, and the scanning line 122 extends in the X-axis direction.

A first interlayer insulating film 126 made of silicon oxide or silicon nitride is formed to cover the semiconductor layer 124a, the source electrode 124b, and the drain electrode 124c, and the first interlayer insulating film 12 is formed.
6 is formed, and a resin layer 127 is formed. Covering the resin layer 127, ITO (Indium Tin O
A lower electrode 128 made of a transparent conductive material such as xide) or IZO (Indium Zinc Oxide) is formed. A second interlayer insulating film 129 made of silicon oxide or silicon nitride generated at a low temperature is formed so as to cover the lower electrode 128, and the surface of the second interlayer insulating film 129 on the liquid crystal layer side is made of ITO, IZO or the like. An upper electrode 130 made of a transparent conductive material is formed. A first alignment film 131 made of polyimide is formed so as to cover the upper electrode 130 and the second interlayer insulating film 129. The first alignment film 131 is rubbed in a predetermined direction.

A contact hole CH that reaches the drain electrode 124c through the first interlayer insulating film 126 and the second interlayer insulating film 129 is formed, and the lower electrode 128 and the drain electrode 124c are electrically connected to each other through the contact hole CH. It is connected. Therefore, in the liquid crystal display panel 1 of the first embodiment, the lower electrode 128 operates as a pixel electrode. The upper electrode 130 includes a strip-like electrode 130b formed by a plurality of slit-like openings 130a extending in the approximate Y-axis direction in FIG. These slit-shaped openings 130a are formed by exposing and etching the upper electrode 130 by photolithography. Here, the upper electrode 130 operates as a counter electrode. The second interlayer insulating film 129 sandwiched between the lower electrode 128 and the upper electrode 130 serves as a dielectric film, and a storage capacity is formed in this portion. In addition,
In an FFS mode liquid crystal display panel, the upper electrode 130 provided with a slit-like opening may be used as a pixel electrode or a counter electrode in order to improve luminance, contrast, etc. Can be applied.

Next, the color filter substrate 14 will be described. The color filter substrate 14 has a substrate body 141 made of glass, quartz, plastic, or the like as a base, and the substrate body 141 includes
A CF (color filter) layer 142 that transmits different color light (for example, R, G, B, colorless, etc.) and a light-shielding material BM (black matrix) layer 143 are formed. A protective resin layer 144 is formed so as to cover the CF layer 142 and the BM layer 143, and the protective resin layer 144 is formed.
A second alignment film 145 made of polyimide is formed so as to cover the surface. Second alignment film 1
45 is rubbed in the opposite direction to the first alignment film 131.

The transmission axis of the polarizing plate 15 on the array substrate 12 side and the transmission axis of the polarizing plate 16 on the color filter substrate 14 side are arranged to be orthogonal to each other, and the transmission axis of the polarizing plate 16 is the Y axis in FIG. Are arranged in parallel. Further, the rubbing direction of the first alignment film 131 is parallel to the transmission axis of the polarizing plate 16. The rubbing direction of the first alignment film 131 is a direction that intersects with the main direction of the electric field generated between the upper electrode 130 and the lower electrode 128. In the initial state, the liquid crystal molecules aligned in parallel along the rubbing direction are rotated and aligned toward the main direction side of the electric field by applying a voltage between the upper electrode 130 and the lower electrode 128. Based on the difference between the initial alignment state and the alignment state at the time of voltage application, the light and dark display of each sub-pixel is performed. In this way, driving display of each sub-pixel is performed. Although not shown, the liquid crystal layer 11 is sealed in a sealing area formed by a sealing material provided between the array substrate 12 and the color filter substrate 14.

Next, the slit-shaped opening 130a of the upper electrode 130 will be described in detail. The electric field is the upper electrode 130.
And the potential difference between the lower electrode 128 positioned in the slit-shaped opening 130a. The electric field is generated substantially parallel to the surface of the array substrate 12, and the direction of the electric field in plan view is the normal direction of the side of the slit-shaped opening 130a. The electric field direction at both ends of the slit-shaped opening 130a is the slit-shaped opening 130a.
The direction is different from the direction of the electric field on the long side. For this reason, reverse twist domains occur at both ends of the slit-shaped opening 130a, resulting in a decrease in the aperture ratio. Since the sub-pixel is vertically long, when the slit-shaped opening 130a extends in the horizontal direction, the slit-shaped opening 130a.
Since the number of both ends of a will increase, an aperture ratio will fall more. Therefore, as shown in FIG. 1, in the liquid crystal display panel 1 according to the first embodiment, by extending the extending direction of the slit-like opening 130a, the number of ends of the slit-like opening 130a is reduced, and the opening is opened. The rate is kept low.

In the liquid crystal display panel 1 of the present embodiment, the slit-shaped opening 13 with respect to the rubbing process direction.
The extending direction of 0a is inclined by a predetermined angle α (for example, about 5 degrees to about 15 degrees). Thereby, the liquid crystal molecules can be rotated in the same direction. If the extending direction of all the slit-shaped openings 130a is inclined in the clockwise direction or the counterclockwise direction, the phenomenon that the color changes depending on the viewing angle direction because the liquid crystal molecules are twisted in one direction. This is because the apparent retardation changes depending on the direction of viewing the liquid crystal molecules. In order to reduce this, in the liquid crystal display panel 1 of the first embodiment, a domain in which the extending direction of the slit-like opening 130a is inclined by + α with respect to the clockwise direction and a domain by which −α is inclined are provided. That is, it is multi-domain. In the liquid crystal display panel 1 of the first embodiment, the number of domains having different alignment directions of the liquid crystal molecules is two, but the number of domains having different alignment directions may be increased.

When the two slit-shaped openings 130a having different extending directions are separated, the slit-shaped openings 13
Since the number of 0a ends increases, the aperture ratio decreases. Therefore, in the present invention, the slit-shaped openings 130a having different extending directions are connected to each other so that the slit-shaped openings 130a are bent into a "<" shape. When the slit-shaped openings 130a having different extending directions are connected in this way, the aperture ratio can be increased as compared with the case where the slit-shaped openings 130a having different extending directions are separated. In the liquid crystal display panel 1 according to the first embodiment, as shown in FIG. 1, the rubbing direction is set to the direction of the base BC of the isosceles triangle ABC having the V-shaped inner angle θ1 as a vertex. Therefore, if one of the inclination angles of the slit-shaped opening 130a with respect to the rubbing direction is + α (the clockwise direction is +), the other is −α, and the absolute value thereof is the same. By the way, when the slit-shaped openings 130a having different extending directions are connected to be folded into a "<" shape, the domains having different orientation directions at the corners folded into the "<" shape. Ripple failure occurs due to the fact that they move back and forth between each other.

Therefore, in the liquid crystal display panel 1 according to the first embodiment, as shown in FIG. 1, the outer corner side of the corner portion folded in a “<” shape is protruded to the outer corner side in a wedge shape. The width of the slit opening at the corner is widened. Domains with different orientation directions are changed because the angle between the rubbing direction and the normal line of the slit-shaped opening 130a is changed by changing the width of the corner portion of the slit-shaped opening 130a that is bent into a "<" shape. Become difficult to go back and forth
Ripple defects can be reduced.

As shown in FIG. 1, in the liquid crystal display panel 1 according to the first embodiment, the side on the outer angle side protrudes in a wedge shape toward the outer angle side, and the angle θ2 of the protruding portion is made smaller than θ1, thereby The width of the slit opening is widened. As shown in FIG. 4, in the corner portion bent in a “<” shape in the liquid crystal display panel 1 of the first embodiment, there is a change in the direction of the electric field in a plan view, and thus the domains having different orientation directions. It becomes difficult to go back and forth between each other. In addition, since the angle formed by the rubbing direction and the electric field direction is small on the outer corner side of the corner portion folded in a “<” shape, a large rotational force is applied to the liquid crystal molecules, and the liquid crystal display panel 1 is temporarily turned on. When the rotation angle of the liquid crystal molecules is changed by being pressed, the original state is easily returned.

In the liquid crystal display panel 1 of the above-described embodiment, the outer corner side of the corner portion folded in a “<” shape is protruded to the outer corner side in a wedge shape, and the corner portion folded in the “<” shape is formed. Although the slit-shaped opening is widened, as shown in FIG. 5, which is a modified example, even if the inner corner side of the corner portion folded in a “<” shape is protruded in a wedge shape, the slit at this corner portion The width of the aperture can be increased. Even in this case, since the direction of the electric field at the corner bent in a “<” shape is changed, it is difficult for domains having different alignment directions of liquid crystal molecules to come and go.

[Second Embodiment]
A liquid crystal display panel 2 according to a second embodiment will be described with reference to FIGS. The liquid crystal display panel 2 of the second embodiment is different in configuration from the liquid crystal display panel 1 of the first embodiment, as shown in FIG.
(1) A slit-like opening 130a formed in the upper electrode 130 and bent in a “<” shape is inclined at a predetermined angle with respect to the vertical direction of the sub-pixel,
(2) The bent part of some slit-like openings 130a communicates with the adjacent slit-like openings;
(3) From the geometrical arrangement of each slit-shaped opening 130a, a part of the slit-shaped openings 130a are formed in a straight line,
(4) The rubbing direction is inclined at a predetermined angle with respect to the long side direction of the sub-pixel,
It is. In the following description, in the liquid crystal display panel 2 of the second embodiment, the same components as those of the liquid crystal display panel 1 of the first embodiment are denoted by the same reference numerals.

In the liquid crystal display panel 2 of the second embodiment, the slit-shaped opening 130 of the upper electrode 130.
Since the extending direction of a is inclined by α with respect to the rubbing direction as in the first embodiment, the slit-shaped opening 130a of the upper electrode 130 is also inclined in accordance with the rubbing. As shown in FIG. 6, the plurality of slit-shaped openings 130a in the liquid crystal display panel 2 of the second embodiment are
What exists in the central part is bent in a "<" shape. However, at the upper and lower portions of the slit-shaped opening 130a in the central portion that is bent in a "<" shape, the corners that are bent in the "<" shape are formed from the geometrical arrangement of the slit-shaped opening 130a. It does not have and is formed in a straight line. The upper slit-shaped opening 130a is inclined by -α (α in the counterclockwise direction) with respect to the rubbing direction, and the lower slit-shaped opening 130a is + with respect to the rubbing direction.
It is tilted α (α in the clockwise direction).

By tilting the rubbing direction in this way, for example, it is possible to reduce a decrease in luminance with respect to an observer using polarized sunglasses, and to cope with a change in the orientation of the liquid crystal display panel used as a display unit for portable devices. You will be able to In the liquid crystal display panel 2 of the second embodiment, the upper electrode 130 provided with the slit-like opening can be a pixel electrode or a counter electrode.

Further, in the liquid crystal display panel 2 of the second embodiment, as shown in FIG. 6, the upper and lower edge lines on the outer corner side of the corner portion folded in a “<” shape are projected to the outer corner side. By making the angle θ3 formed by the upper and lower edge lines of the portion smaller than θ1, the width of the slit-like opening at the corner portion is widened. In the liquid crystal display panel 2 of the second embodiment, a slit-shaped opening 130a adjacent to a part of the opening protruding outward from the corner portion folded in the “<” shape.
Communicated with. In this way, if a part of the opening protruding outward from the corner portion folded in the shape of “<” is communicated with the adjacent slit-like opening 130 a, it becomes difficult to apply a voltage to the liquid crystal molecules. The rotation becomes smaller and reverse twist is less likely to occur.
In this example, the rubbing direction is inclined at a predetermined angle with respect to the long side direction of the sub-pixel. It becomes possible to reduce a decrease in luminance with respect to the observer used, and to cope with a change in the orientation of a liquid crystal display panel used as a display unit for a portable device.

[Third Embodiment]
A liquid crystal display panel 3 according to a third embodiment will be described with reference to FIGS. The difference between the liquid crystal display panel 3 of the third embodiment and the liquid crystal display panel 1 of the first embodiment is that (1) the bending start point for widening the slit width is the liquid crystal display of the first embodiment. The panel 1 is provided at a corner bent in a “<” shape, whereas the liquid crystal display panel 3 of the third embodiment is located in a vicinity slightly away from the corner bent in a “<” shape. The provided points,
(2) In the liquid crystal display panel 1 of the first embodiment, only the outer corner side of the corner portion bent in a “<” shape is projected outward, whereas the liquid crystal display panel of the third embodiment 3 is a point where both the inner corner side and the outer corner side of the corner portion folded in a “<” shape are projected to the outer corner side,
It is. In the liquid crystal display panel 3 of the third embodiment, the same components as those of the liquid crystal display panel 1 of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

In the liquid crystal display panel 3 of the third embodiment, as shown in FIG. 7, the rubbing direction is the vertical (Y-axis) direction as in the case of the liquid crystal display panel 1 of the first embodiment. The slit-shaped opening 130a is a slit-shaped opening that is bent into a two-step "<" shape by projecting to the outer corner side while the width of the slit-shaped opening gradually increases in width. It has become. In the liquid crystal display panel 3 of the third embodiment, the angle θ5 formed by the inner angle side of the corner portion folded in a “<” shape is larger than the angle θ1 formed by the extending directions of both ends of the slit-shaped opening 130a. Further, the angle θ4 formed by the outer angle side of the corner is smaller than θ5. FIG. 8 shows the rotation state of the liquid crystal molecules at the corners folded in a “<” shape in this case. In the liquid crystal display panel 3 of the third embodiment, the angle formed by the rubbing direction and the electric field direction is small at the corner portion folded in a “<” shape. Therefore, since a large rotational force is applied to the liquid crystal molecules, even if the liquid crystal display panel 3 is temporarily pressed to change the rotation angle of the liquid crystal molecules, it easily returns to the original state.

The length of the bent portion (L3 in FIG. 8) of the liquid crystal display panel 3 of the third embodiment is set longer than the length of the bent portion (L1 in FIG. 4) of the liquid crystal display panel 1 of the first embodiment. The In such a configuration, since the corner portion bent in a “<” shape has a different electric field direction from the other portions, the number of regions having different VT characteristics increases. Can be reduced.

[Fourth Embodiment]
A liquid crystal display panel 4 according to a fourth embodiment will be described with reference to FIGS. In the liquid crystal display panel 4 of the fourth embodiment, slit-like openings having different extending directions and the same width are connected by being folded into a “<” shape, and the corner portion folded into this “<” shape. The first is that the width of the corner portion is widened by bending the outer corner side of the lens to the outer corner side like a wedge.
This is the same as the case of the liquid crystal display panel 1 of the embodiment. However, in the liquid crystal display panel 4 of the fourth embodiment, the slit-shaped opening having the same width is weakened even in the vicinity of the corner portion folded in a “<” shape and is folded in a “<” shape in two steps. The configuration is different from the liquid crystal display panel 1 of the first embodiment in that it has a “<”-shaped bent portion. Note that, in the liquid crystal display panel 4 of the fourth embodiment, the same components as those of the liquid crystal display panel 1 of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

In the liquid crystal display panel 4 of the fourth embodiment, as shown in FIG. 9, the rubbing direction is the vertical (Y-axis) direction as in the case of the liquid crystal display panel 1 of the first embodiment. In the liquid crystal display panel 4 of the fourth embodiment, the angle θ1 formed by the extending directions of both ends of the slit-shaped opening 130a.
Than the angle formed by the inner angle side of the corner (the same as the angle formed by the outer angle side) θ7,
The angle θ6 formed by the portion of the corner portion on the outer angle side protruding toward the outer angle side is smaller than θ7.

In the liquid crystal display panel 4 of the fourth embodiment, as shown in FIG. 10, the rubbing is performed at the corner portion folded in the “<” shape and the weak “<” shape in the vicinity thereof. The angle between the direction of and the direction of the electric field is small. For this reason, a large rotational force is applied to the liquid crystal molecules, and even when the liquid crystal display panel 4 is temporarily pressed to change the rotation angle of the liquid crystal molecules, it easily returns to the original state.

The total length of the bent portion and the bent portion of the liquid crystal display panel 4 of the fourth embodiment (L4 in FIG. 10).
) Is longer than the length of the bent portion (L1 in FIG. 4) of the liquid crystal display panel 1 of the first embodiment. In the corner portion and the bent portion of the liquid crystal display panel 4 according to the fourth embodiment which are bent in a “<” shape, the electric field direction is different from the other portions, so that regions having different VT characteristics are increased. The color difference due to the viewing angle can be reduced.

In the liquid crystal display panel of each of the above-described embodiments, the direction of the slit-shaped opening is the vertical direction or the oblique direction. However, the present invention is not limited to this, and the slit-shaped opening is in the case of being oriented horizontally. Are equally applicable. Moreover, although the bending part of the slit-shaped opening of each embodiment described above has a single “<” shape, it can be applied to a zigzag slit shape having a plurality of bending parts. Further, in the liquid crystal display panel of each of the above-described embodiments, the portion bent from the corner portion bent in a “<” shape to the inner corner side or the outer corner side is linear, but if the direction of the electric field changes, Since it is good, it may be curved.

It is a front view for 1 sub pixel which shows the slit-shaped opening of the liquid crystal display panel which concerns on 1st Embodiment. It is sectional drawing along the II-II line of FIG. It is sectional drawing along the III-III line of FIG. It is a figure which shows the rotation state of the liquid crystal molecule in 1st Embodiment. It is a figure which shows the rotation state of the liquid crystal molecule in the modification of 1st Embodiment. It is a front view for 1 sub pixel which shows the slit-shaped opening of the liquid crystal display panel which concerns on 2nd Embodiment. It is a front view for 1 sub pixel which shows the slit-shaped opening of the liquid crystal display panel which concerns on 3rd Embodiment. It is a figure which shows the rotation state of the liquid crystal molecule in 3rd Embodiment. It is a front view for 1 sub pixel which shows the slit-shaped opening of the liquid crystal display panel which concerns on 4th Embodiment. It is a figure which shows the rotation state of the liquid crystal molecule in 4th Embodiment.

Explanation of symbols

1-4: Display panel 11: Liquid crystal layer 111: Spacer 12: Array substrate 121: Substrate body (array substrate) 122: Scanning line 122a: Gate electrode 123: Gate insulating film 124: TFT 124a: Semiconductor layer 124b: Source electrode 124c : Drain electrode 125: data line 126: first interlayer insulating film 127: resin layer (array substrate) 12
8: Lower electrode 129: Second interlayer insulating film 130: Upper electrode 130a: Slit 131:
First alignment film 14: Color filter substrate 141: Substrate body (color filter substrate) 1
42: CF layer 143: BM layer 144: Resin layer (color filter substrate) 145: Second
Alignment film 15: First polarizing plate 16: Second polarizing plate 17: Backlight CH: Contact hole

Claims (6)

A pair of substrates disposed opposite to each other with a liquid crystal layer interposed therebetween, an upper electrode having a plurality of slit-like openings on one of the pair of substrates, and formed on the substrate side through the upper electrode and an insulating layer In the liquid crystal display panel comprising the lower electrode formed and an alignment film formed on the liquid crystal layer side,
The slit-shaped opening is bent in a “<” shape, and a corner where the width of the slit-shaped opening is wide is formed in the corner portion bent in the “<” shape. A characteristic LCD panel. The part where the width of the slit-shaped opening is wide is formed by protruding the outer corner side of the corner portion of the slit-shaped opening bent in a “<” shape to the outer angle side like a wedge. The liquid crystal display panel according to claim 1, wherein the liquid crystal display panel is a liquid crystal display panel. The part where the width of the slit-shaped opening is wide is formed by projecting the inner corner side of the corner portion of the slit-shaped opening bent in a “<” shape into a wedge shape toward the inner corner side. The liquid crystal display panel according to claim 1, wherein: The width of the slit-shaped opening is widened so that the width of the slit-shaped opening at the corner portion of the slit-shaped opening is continuously increased. 2. The liquid crystal panel according to claim 1, wherein both sides of the liquid crystal panel are formed by projecting both sides to the outer angle side. The portion where the width of the slit-shaped opening is wide is formed in a state where the portion of the same width of the slit-shaped opening is once bent to the outer corner side, and is further bent into a “<” shape of the slit-shaped opening. The liquid crystal display panel according to claim 1, wherein the liquid crystal display panel is formed by projecting the outer corner side of the corner portion to the outer corner side in a wedge shape. The liquid crystal display panel according to claim 1, wherein a portion where the width of the slit-shaped opening is wide is communicated with an adjacent slit-shaped opening in the same pixel region.

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