JP2010002448A - 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 1 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 is bent in the form of the dogleg, and a part in which width of the slit-like opening is narrowed 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 both ends of the slit-shaped opening cannot form an electric field in a desired direction, if the slit-shaped openings having different extending directions are separated, the aperture ratio is lowered. 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

When two slit-like openings having different extending directions are formed, regions (domains) having different orientation directions of 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 is to provide a liquid crystal display panel in which ripple defects are reduced by reducing the number of domains having different alignment directions of liquid crystal molecules at the 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 narrow slit-like opening is formed in the corner part that is bent in a “<” shape.

According to the crystal display panel of the present invention, the width of the slit-like opening at the corner bent in a “<” shape is narrow, and the rubbing direction and the side of the slit-like opening are formed at this corner. Since the corner changes, domains in which the orientation directions of the liquid crystal molecules on both sides of the corner portion are difficult to go back and forth, and ripple defects can be reduced.

Further, in the liquid crystal display panel of the present invention, the narrowed 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 bending to the outer angle side.

According to the liquid crystal display panel of this aspect, the angle formed by the rubbing direction and the side of the slit-shaped opening is larger than the other portion on the inner corner side of the corner portion folded in a “<” shape, and the plan view Since the change in the direction of the electric field at this point becomes large, domains having different alignment directions of the liquid crystal molecules on both sides of the corners are difficult to go back and forth. In addition, since the angle formed between the rubbing direction and the direction of the electric field is reduced on the inner angle side of the corner portion, and a large rotational force is obtained with respect to the liquid crystal molecules, the surface of the liquid crystal display panel is temporarily pressed and the liquid crystal Even if a ripple occurs due to a change in the rotation angle of the molecule, it easily returns to the original state.

Further, in the liquid crystal display panel of the present invention, the portion where the width of the slit-shaped opening is narrowed is such that the outer corner side of the corner portion of the slit-shaped opening bent in a “<” shape is wedge-shaped. It is preferably formed by bending to the inner angle side.

According to the liquid crystal display panel of this aspect, the direction of the electric field can be changed also by bending the side on the outer angle side in a wedge shape toward the inner angle side, and the domain in which the alignment directions of the liquid crystal molecules are different as in the case of the above invention. It becomes difficult to go back and forth between each other.

Further, in the liquid crystal display panel of the present invention, the width of the slit-shaped opening that is bent in the “<” shape of the slit-shaped opening is continuous with the narrowed portion of the slit-shaped opening. It is preferable that the inner angle side and the outer angle side are both bent to the outer angle side so as to be smaller.

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 the shape of “<”, 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 on both the inner corner side and the outer corner side of the corner that is bent in a “<” shape, regions with different VT (voltage-transmittance) characteristics increase. Therefore, the color difference due to the viewing angle can be reduced.

Further, in the liquid crystal display panel of the present invention, the portion where the width of the slit-like opening is narrowed is formed in a state where a portion of the same width of the slit-like opening is once bent to the outside angle side, and further, the slit It is preferable to be formed by bending the inner corner side of the corner portion that is bent into the “<” shape of the shaped opening into a wedge shape to the outer corner 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 the shape of “<”, so that a large rotational force is given to the liquid crystal molecules. Will be able to. Therefore, when the liquid crystal display panel is temporarily pressed and the rotation angle of the liquid crystal molecules changes, it becomes easier to return to the original rotation angle. 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.

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 showing a rotation state of liquid crystal molecules in the first embodiment. FIG.
These are the enlarged views of the bending part of the modification of 1st Embodiment. FIG. 6 is a front view of one sub-pixel showing a slit-like opening of the liquid crystal display panel according to the second embodiment. 7 shows the VII-V in FIG.
It is sectional drawing along the II line. FIG. 8 is a sectional view taken along line VIII-VIII in FIG. FIG. 9 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. 10 is a diagram showing a rotation state of liquid crystal molecules in the third embodiment. FIG. 11 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.
These are figures which show the rotation state of the liquid crystal molecule in a 4th aspect.

[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 124a 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 122a of the TFT 124 in the facing region. The source electrode 124b is branched from the signal line 125. The signal line 125 extends in the Y-axis direction in 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 upper electrode 130 and the drain electrode 124c are electrically connected via the contact hole CH. It is connected. Therefore, in the liquid crystal display panel 1 of the first embodiment, the upper electrode 130 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. The slit-shaped opening 130a is formed by exposing and etching the upper electrode 130 by photolithography. Lower electrode 128 and upper electrode 1
The second interlayer insulating film 129 sandwiched between the lower electrode 128 and the upper electrode 130 forms a storage capacity between the lower electrode 128 and the upper electrode 130. Note that in an FFS mode liquid crystal display panel, the upper electrode 130 provided with a slit-like opening may be a pixel electrode or a counter electrode in order to improve luminance, contrast, and the like. It can also be applied to.

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 of the electric field on the long side is different from the direction. For this reason, a reverse twist domain is generated to lower the aperture ratio. Further, since an area for closing the slit-shaped opening 130a is required, the aperture ratio is reduced in the vicinity of both ends of the slit-shaped opening 130a. Since the sub-pixel is vertically long, if the slit-shaped opening 130a is extended in the horizontal direction, the number of both ends of the slit-shaped opening 130a increases and the aperture ratio decreases. Therefore, as shown in FIG. 1, in the liquid crystal display panel 1 of the first embodiment, the slit-shaped opening 1 is formed by extending the extending direction of the slit-shaped opening 130a vertically.
By reducing the number of end portions of 30a, the aperture ratio is prevented from being lowered.

The extending direction of the slit-shaped opening 130a with respect to the rubbing direction is set to a predetermined angle α (for example, about 5
Tilt to about 15 degrees. Thereby, the liquid crystal molecules can be rotated in the same direction. When all the slit-shaped openings 130a are clockwise or counterclockwise, the liquid crystal molecules are twisted in one direction, so that a phenomenon in which the color changes depending on the viewing angle direction appears. 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-shaped 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 according to the first embodiment, the number of domains having different alignment directions is two. However, the number of domains having different alignment directions may be increased.

When the slit-shaped openings 130a of the two slit-shaped openings 130a having different extending directions are separated, the end portions of the slit-shaped openings 130a are increased, so that the aperture ratio is decreased. Therefore, in the present invention, slit-like openings 130a having different extending directions are connected to make the slit-like openings 130a "
It shall be in the state bent in the shape of "<". As described above, the slit-shaped opening 130a having different extending directions.
As a result, 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, an isosceles triangle ABC whose apex is an inner angle θ <b> 1 of a corner portion where the slit-like opening 130 a is bent in a “U” shape in the rubbing direction. In the direction of the base BC. 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 and bent into a “<” shape, this “
In the corners bent in a “<” shape, domains having different orientation directions come and go to each other, resulting in a ripple failure.

Therefore, in the liquid crystal display panel 1 according to the first embodiment, as shown in FIG. 1, by bending the inner corner side of the corner portion folded in a “<” shape to the outer corner side in a wedge shape, The width of the slit-like opening at the corner is narrowed. 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 of the first embodiment, the angle θ2 of the corner portion bent in a wedge shape by bending the inner corner side to the outer corner side from the angle θ1. Also, the width of the slit-shaped opening 130a at the corner is narrowed. 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 inner 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 according to the first embodiment described above, the inner corner side of the corner portion bent in a “<” shape is bent in a wedge shape toward the outer corner side and bent in a “<” shape. Although the example in which the width of the slit-like opening at the corner portion is narrowed is shown, as shown in FIG. 5 which is a modified example, the outer corner side of the corner portion folded in a “<” shape is wedge-shaped toward the inner corner side. Even if it is bent, the width of the slit-like opening at the corner bent in a “<” shape can be reduced. 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 “<”-shaped slit-shaped opening 130 a formed in the upper electrode 130 is formed at a predetermined angle with respect to the vertical direction (Y-axis direction) of the sub-pixel,
(2) From the geometrical arrangement of the respective slit-shaped openings 130a, some of the slit-shaped openings 130a do not have corners bent in a “<” shape and are formed in a straight line. point,
(3) The rubbing direction is inclined at a predetermined angle with respect to the long side direction of the sub-pixel,
(4) The upper electrode 130 operates as a counter electrode and the lower electrode 128 operates as a pixel electrode.
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.

As shown in FIGS. 7 and 8, the liquid crystal display panel 2 according to the second embodiment includes a liquid crystal layer 11 as an array substrate 12 and a color filter substrate as in the case of the liquid crystal display panel 1 according to the first embodiment. 14 is sandwiched. The thickness of the liquid crystal layer 11 is held 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 for irradiating light is disposed on the back side of the array substrate 12.

Hereinafter, the configuration of the array substrate 12 in the liquid crystal display panel 2 of the second embodiment will be described. The array substrate 12 of the second embodiment is the same as the liquid crystal display panel 1 of the first embodiment.
As in the case of the array substrate 12, the TFT 124 constituted by the scanning line 122 having the gate electrode 122 a from the back side to the substrate body 121 side, the gate insulating film 123, the semiconductor layer 124 a, the source electrode 124 b and the drain electrode 124 c. It has. The source electrode 124b is branched from the signal line 125. The signal line 125 extends in the Y-axis direction in FIG. 6, 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, a resin layer 127 is formed. A lower electrode 128 is formed to cover the resin layer 127. 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. The contact hole CH
The lower electrode 128 and the drain electrode 124c are electrically connected via each other. for that reason,
In the liquid crystal display panel 2 of the second embodiment, the lower electrode 128 operates as a pixel electrode.

A second interlayer insulating film 129 made of silicon oxide, silicon nitride or the like generated at a low temperature is formed to cover the lower electrode 128. On the surface of the second interlayer insulating film 129 on the liquid crystal layer side, ITO, IZ
An upper electrode 130 made of a transparent conductive material such as O is formed. The upper electrode 130 operates as a counter electrode. The first alignment film 13 covers the upper electrode 130 and the second interlayer insulating film 129.
1 is formed. The upper electrode 130 has a plurality of slit-shaped openings 130 as shown in FIG.
A strip electrode 130b formed of a is provided. The second interlayer insulating film 129 sandwiched between the upper electrode 130 and the lower electrode 128 serves as a dielectric film, and a storage capacity is formed between the upper electrode 130 and the lower electrode 128. 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.

As in the case of the liquid crystal display panel 1 of the first embodiment, the color filter substrate 14 in the liquid crystal display panel 2 of the second embodiment has a CF layer 142, a light shielding material BM layer 143, and a resin layer on the substrate body 141. 144 and a second alignment film 145 are formed. The first alignment film 131 and the second alignment film 145 of the second embodiment are rubbed in opposite directions. The rubbing direction of the first embodiment is the vertical direction, but the rubbing direction of the second embodiment is as shown in FIG.
It is inclined at a predetermined angle (for example, 20 degrees) with respect to the long side direction of the sub-pixel.

Since the extending direction of the slit-shaped opening 130a of the upper electrode 130 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 direction. ing. As shown in FIG. 6, the liquid crystal display panel 2 of the second embodiment.
In the plurality of slit-shaped openings 130a, the one present in the central portion is bent into a "<" shape. However, in the upper part and the lower part of the slit-shaped opening 130a in the central portion that is bent in a "<" shape, from the geometrical arrangement of the slit-shaped opening 130a, "
It does not have corners bent in a "<" shape and is formed in a straight line. The upper slit-shaped opening 130a is tilted by -α (counterclockwise α) with respect to the rubbing direction, and the lower slit-shaped opening 130a is tilted + α (clockwise α) with respect to the rubbing 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-shaped opening 130a can be a pixel electrode or a counter electrode. In addition, the “<”-shaped slit-shaped opening 130 a formed in the upper electrode 130 in the liquid crystal display panel 2 of the second embodiment is formed at a predetermined angle with respect to the vertical direction (Y-axis direction) of the sub-pixel. The example which made it become vertically long by doing was shown. However, the “<”-shaped slit-shaped opening 130 a may be horizontally long by being inclined at a predetermined angle with respect to the horizontal direction (X-axis direction) of the sub-pixel.

[Third Embodiment]
A liquid crystal display panel 3 according to a third embodiment will be described with reference to FIGS. This third
The liquid crystal display panel 3 of this embodiment is different from the liquid crystal display panel 1 of the first embodiment in that the liquid crystal display panel 1 of the first embodiment starts bending to narrow the width of the slit-shaped opening. Whereas the point is provided at a corner bent in a “<” shape, the liquid crystal display panel 3 according to the third embodiment has a bending start point a little from the corner bent in a “<” shape. This is a point provided in the vicinity of the space. Further, in the liquid crystal display panel 3 of the third embodiment, the upper electrode 130 provided with the slit-shaped opening 130a operates as a counter electrode, as in the case of the liquid crystal display panel 2 of the second embodiment. 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.

As shown in FIG. 9, in the liquid crystal display panel 3 of the third embodiment, 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 that is bent into a two-step "<" shape by bending the corners bent in a "<" shape gradually toward the outer corner while the width of the slit-shaped opening gradually decreases. It has become. In the liquid crystal display panel 3 of the third embodiment, the angle θ5 formed by the side on the outer 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. Furthermore, the angle θ4 formed by the side on the inner angle side of the corner is smaller than θ5. FIG. 10 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 given to the liquid crystal molecules, even if the liquid crystal display panel 3 is temporarily pressed and the rotation angle of the liquid crystal molecules changes,
It becomes easy to return to the original state.

The length of the bent portion of the liquid crystal display panel 3 of the third embodiment (L3 in FIG. 10) is longer than the length of the bent portion of the liquid crystal display panel 1 of the first embodiment (L1 in FIGS. 4 to 5). Set long. 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]
The liquid crystal display panel 4 according to the fourth embodiment bends slit-like openings having different extending directions and the same width into a “<” shape, and the inner corner side of the corner portion folded into this “<” shape. The first side is that the width of the corner is reduced by bending the side of the
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. In the liquid crystal display panel 4 of the fourth embodiment, the upper electrode 130 provided with the slit-shaped opening operates as a counter electrode as in the case of the liquid crystal display panel 2 of the second embodiment. Moreover, in the liquid crystal display panel 4 of 4th Embodiment, the same referential mark is provided to the same component as the liquid crystal display panel 1 of 1st Embodiment, and the detailed description is abbreviate | omitted.

In the liquid crystal display panel 4 of the fourth embodiment, as shown in FIG. 11, 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 θ formed by the extending directions of both ends of the slit-shaped opening 130a.
The angle θ7 formed by the inner angle side of the corner is smaller than 1, and the angle θ6 formed by the bent portion of the inner angle side of the corner toward the outer angle is smaller than θ7.

In the liquid crystal display panel 4 of the fourth embodiment, the angle formed between the rubbing direction and the electric field direction at the corner portion folded in a “<” shape and in a weakly “<” shape near the corner portion. Is getting smaller. 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. 12).
) Is longer than the length (L1 in FIGS. 4 to 5) of the bent portion of the liquid crystal display panel 1 of the first embodiment. In the corner portion of the liquid crystal display panel 4 of the fourth embodiment which is bent in a “<” shape, the electric field direction is different from the other portions, so that the region having different VT characteristics increases, and the viewing angle is increased. The color difference due to 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 a 1st aspect. It is an enlarged view of the bending part of 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 sectional drawing along the VII-VII line of FIG. It is sectional drawing along the VIII-VIII line of FIG. 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 a 3rd aspect. 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 a 4th aspect.

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: signal line 126: first interlayer insulating film 127: resin layer (array substrate) 128
: 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) 14
2: 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 (5)

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 narrowed is formed in the corner portion bent in the “<” shape. A characteristic LCD panel. The portion where the width of the slit-like opening is narrowed is formed by bending the inner corner side of the corner portion of the slit-like opening bent in a “<” shape to the outer corner side like a wedge. The liquid crystal display panel according to claim 1, wherein: The portion where the width of the slit-like opening is narrowed is formed by bending the outer corner side of the corner portion of the slit-like opening bent in a “<” shape into a wedge shape to the inner corner side. The liquid crystal display panel according to claim 1, wherein: The width of the slit-shaped opening is narrowed so that the width of the slit-shaped opening at the corner of the slit-shaped opening is continuously reduced. The liquid crystal panel according to claim 1, wherein both sides of the liquid crystal panel are formed by bending them to the outer angle side. A portion where the width of the slit-like opening is narrowed is formed in a state where the same-width portion of the slit-like opening is once bent to the outer corner side, and is further bent into a “<” shape of the slit-like opening. The liquid crystal display panel according to claim 1, wherein the liquid crystal display panel is formed by bending the inner corner side of the corner portion to the outer corner side in a wedge shape.

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