JPH09211476A - Sprit electrode type liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display which achieves a high contrast and high reliability, relating to a split electrode type liquid crystal display device having a circular opening on a picture element electrode. SOLUTION: A picture element electrode is provided a circular opening designed so that the area of the circular opening 303 is made large (306) in an instability-prone area of liquid crystal orientation in a picture element 302, while the area of the circular opening 303 is made small (307) in a relatively stable area of the orientation. By designing the circular opening 303 considering the difference in the stability of the liquid crystal orientation in the picture element, a stability of a liquid crystal domain and an improvement in contrast are made compatible, and a high contrast and high reliable panel is realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode split type liquid crystal display device having excellent viewing angle characteristics.

[0002]

2. Description of the Related Art A liquid crystal display is a display characterized by being thin, lightweight and low power consumption, and is widely used as a display screen of a word processor or a television.

Among the liquid crystal display devices, an active matrix type liquid crystal display device in which a large number of switching elements are arranged on an array substrate displays a twisted nematic mode (hereinafter, TN mode) in which the orientation of liquid crystal is twisted by substantially 90 °. It is being used as a display and is being developed as a display capable of high-speed response and high definition.

However, the TN mode liquid crystal display device has a major drawback in that the color tone and the contrast are different depending on the viewing angle of the panel because the liquid crystal display device uses the optical rotatory power of the liquid crystal.

For this reason, the viewing angle range in which a good display is obtained is considerably narrower than that of a cathode ray tube (CRT), and a display performance equal to or higher than that of a CRT has not been realized yet.

Normally, an active matrix type liquid crystal display device uses a normally white mode (hereinafter, NW mode) in which white display is performed in the state where no voltage is applied.

In the NW mode, since the polarizing plates are arranged orthogonally on both sides of the panel, black display can be easily obtained and the contrast can be increased. Also, even if the panel gap is slightly different, the display hue does not change significantly, which is excellent in construction method. However, the viewing angle range is considerably narrower than that of a CRT.

The electrode division method is known as a method for widening the viewing angle of such an NW mode active matrix type liquid crystal display device.

Electrode division method (for example, A. Lien, et al, Socie
ty of information display 93 dijest P.269) has a rectangular hole in a part of the counter electrode of the pixel, and distorts the electric field distribution in the panel to create multiple regions in the pixel, and Azimuth is averaged to achieve a wide viewing angle.

[0010]

Such an electrode division method is an effective method for enlarging the viewing angle of a liquid crystal panel, but since the liquid crystal in the holes provided in the electrodes does not respond to the driving, black display on the panel is performed. However, there is a problem that whitening occurs and the contrast is lowered.

In this case, if a light shielding portion is provided in the hole portion, the contrast is improved, but the problem that the panel brightness is lowered occurs.

Therefore, in the electrode division method, it is necessary to further improve the contrast while maintaining the panel brightness.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems of the conventional electrode division method and to realize an electrode division type liquid crystal display device of high contrast and high brightness.

[0014]

According to the present invention, there is provided a liquid crystal including, as a component, a liquid crystal panel including a substrate including a pixel electrode having holes in at least a part of a region, a substrate including a transparent electrode, and a liquid crystal. In the display device, the shape of the holes formed in the pixel electrode has different portions in the pixel electrode, which is an electrode division type liquid crystal display device.

The present invention provides a liquid crystal display including as its components a liquid crystal panel including a substrate including a pixel electrode having a substantially slit-shaped hole in at least a part of a region, a substrate including a transparent electrode, and a liquid crystal. In the device, when the hole width near the pixel end of the pixel electrode is L1 and the hole width near the center of the pixel electrode is L2, the relationship of L1> L2 is established. It is a split type liquid crystal display device.

According to the present invention, there is provided an electrode division including a liquid crystal panel having a substrate including a pixel electrode having substantially slit-shaped holes in at least a part of a region, a substrate including a transparent electrode, and a liquid crystal as a component. A liquid crystal display device of the electrode type, wherein the holes have a shape having at least one protrusion on the long side of the slit.

According to the present invention, an electrode division including a liquid crystal panel having a substrate including a pixel electrode having substantially slit-shaped holes in at least a part of a region, a substrate including a transparent electrode, and a liquid crystal as constituent elements. In a liquid crystal display device, the hole has a shape having a protrusion on the long side of the slit,
Further, the area of the protrusion near the pixel end of the pixel electrode is S1,
The electrode split type liquid crystal display device is characterized in that a relationship of S1> S2 is established, where S2 is an area of the protrusion near the center of the pixel electrode.

The present invention is directed to an electrode split type liquid crystal display including a liquid crystal panel including a substrate including a pixel electrode having a plurality of holes in at least a part of a region, a substrate including a transparent electrode, and a liquid crystal as constituent elements. In the device, the shape of the holes is substantially circular or polygonal, and the area of the circular or polygonal holes is different in the area of the pixel electrode. Is.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

In the electrode split type panel, a region where liquid crystal orientation is different is created by utilizing distortion of an electric field inside the panel generated by forming a hole in a counter electrode or a part of a pixel electrode, and a wide viewing angle is obtained. Is a method of realizing. The operation principle of the electrode split type panel will be briefly described below.

FIG. 1 is a sectional view of one pixel of the electrode division type liquid crystal panel. FIG. 1 is an exploded view showing a black display state in which a voltage is applied by disposing a splay twist alignment TFT (Thin film transistors) type liquid crystal panel between polarizing plates 100 and 101 set to crossed nicols. There is. There is a hole 103 in the center of the pixel electrode 104.

When a voltage is applied between the pixel electrode 104 and the counter electrode 102, the electric lines of force A 106 and the lines of electric force due to the lateral electric field from the source line 105 are representative of the lines of electric force in the panel. D109, and lines of electric force B107 and lines of electric force C108 due to the vertical electric field between the substrates.
At this time, the orientation of the liquid crystal in the domain A110 is determined by the directions of the electric fields of the electric force lines A106 and B107, and similarly, the orientation of the other domain B111 is determined by the electric force lines C108 and D109. Domain A
Regarding the orientations of 110 and the domain B111, the viewing angle directions of the liquid crystal are different from each other by 180 °. Therefore, the viewing angle characteristics of the panel are averaged in the display pixels, gradation inversion on the main viewing angle side is substantially eliminated, and at the same time, the contrast on the anti-main viewing angle side is improved and the viewing angle is expanded. Therefore, the following two points are extremely important items in order to create the electrode split type panel.

(1) Immediately after applying a voltage, domains of liquid crystal having different alignment states are generated in a pixel.

(2) The generated domain is allowed to exist stably in the pixel.

As shown in FIG. 1, the domains A110 and B111 which are in different orientations exist stably only when the boundaries of the domains exist in the region of the holes 103. This is because the liquid crystal in the area of the hole 103 is
This is because it does not respond to the electric field and acts as a kind of buffer band for the two domains. In this way, if the holes fill the role of a buffer zone, the force exerted by one domain on the other domain is mitigated by the holes, and the domain crosses the holes and progresses to the other domain region. There is no.

From the above, in order to make the domains stably exist in the pixel in the electrode split type panel, the holes 103 are required.
It turns out that the design of is important. At this time, the larger the holes, the effect of generating domains due to the distortion of the electric field,
The effect of allowing the generated domains to exist stably is increased, and an electrode split type panel with stable orientation and high reliability is produced.

On the other hand, in order to improve the contrast while maintaining the volatility of the electrode split type panel, it is important to suppress the whitening in the black display. Whitening is caused by light leakage due to a disclination line generated when a voltage is applied. In this case, the shape and size of the light leakage area of the electrode split type panel are substantially equal to the shape and size of the holes of the counter electrode. Therefore, in order to improve the contrast, the smaller the void, the better.

From the above, in order to produce an electrode split type panel having high contrast, stable orientation and high reliability, it is necessary to optimize the design of the hole shape formed in the electrode. In this case, it is necessary to make the area of the pores as small as possible and the shape of the pores in which the domains of the liquid crystal having different alignment states can exist stably so that the contrast becomes sufficiently high.

In order for the reverse tilt tilt line generated at the domain boundary to exist stably in the hole of the electrode, it is necessary to reduce the force that acts when the reverse tilt tilt line moves in the hole. There is. In general, such a force acting on the reverse tilt rolling line differs depending on the shape of the rolling line. The reverse tilt tilt line deforms the shape such that the energy of the tilt line is minimized. Therefore, for example, the tilt line that is bent at an acute angle in the middle is usually transformed into a straight line or an arc having a small curvature.

In other words, this means that when the boundaries of different domains are straight and when they form an acute angle, the minimum tilt necessary for stabilizing the reverse tilt tilt line by trapping it in the holes. It means that the size of is different.

In this case, the width of the hole in the portion where the reverse tilt tilt line forms an acute angle is L1, and the width of the hole in the portion where the reverse tilt tilt line forms the straight line is L2.
Then, the relationship of L1> L2 holds for the minimum hole width required to stabilize the tilt line.

The shape of the reverse tilt tilt line generated in the pixel of the electrode division type panel is an acute angle near the edge of the pixel and a straight line at the center of the pixel. Therefore, when the hole width near the edge of the pixel is L1 and the hole width at the center of the pixel is L2,
If the relationship of L1> L2 is satisfied, it is not necessary to unnecessarily widen the voids, and an electrode split type panel with stable orientation can be produced while maintaining high contrast.

The effect of catching and stabilizing the reverse tilt roll line on the holes depends on not only the hole width, that is, the area of the holes, but also the fine shape of the holes. In this case, if the holes have fine irregularities, the effect of stabilizing the tilt line is greater. This is because an attractive force acts between the fine irregularities and the tilt line. Therefore, by providing the protrusions on the side surfaces of the slit-shaped holes, the tilt line can be effectively stabilized.

By combining the area of the holes and the effect of the fine protrusions, the holes having a shape having protrusions on the side surfaces of the long side of the slit are used, and the area of the protrusions near the edge of the pixel is S1. When the area of the protrusion near the center of the pixel is S2, if the relationship of S1> S2 is satisfied, the tilt line can be further stabilized.

In addition, by the same action, a structure in which a plurality of circular holes are arranged on the electrodes in the pixel and the reverse tilt tilt line is stabilized even if the area of the circular holes is changed in the pixel region. Can be made.

Further, similarly, a structure in which a plurality of polygonal holes are arranged on the electrodes in the pixel stabilizes the reverse tilt tilt line even if the area of the polygonal holes is changed in the pixel region. be able to.

Next, the present invention will be described more specifically.

(Embodiment 1) FIG. 2 shows a sectional view of one pixel of an electrode split type liquid crystal panel used in the first electrode split type liquid crystal display device of the present invention. A pixel electrode 201, a source line 202, a passivation film 203, and the like are formed on the array substrate 200 by using a method of vacuum vapor deposition and etching,
The active matrix substrate was used. At this time, in order to form holes in the pixel electrode 201, a positive resist was applied in the shape of holes using a photomask. OFPR5000 (manufactured by Tokyo Applied Chemistry) was used as a resist. After that, the pixel electrode 201 was etched using a hydrogen iodide solution to form a hole 209 in the electrode. Hole 20
No. 9 was formed in a shape in which the line width is different in the pixel from the center of the source line 202 in parallel with the gate line. further,
The alignment film 204 was printed on the substrate using a printing method. After printing the alignment film 206 on the counter substrate, the alignment film was cured in an oven.

Next, the array substrate 200 and the counter substrate 208
Was rubbed with a nylon cloth. At this time, rubbing was performed so that the liquid crystal orientation after liquid crystal injection was 90 ° splay twist orientation between the substrates. The array substrate 200 and the counter substrate 208 were attached to each other at intervals of 5 μm using a glass spacer.

Finally, ZLI-47 which is a fluorine-based liquid crystal
92 (manufactured by Merck & Co., Inc.) was injected into the panel using a vacuum injection method to prepare an electrode split type panel.

FIG. 3 is a schematic view of one pixel of the prepared electrode division type panel. The pixel electrode 302 is surrounded by the source line 300 and the gate line 301. At this time, the size of the pixel electrode 302 is 100 μm along the source line 300 and 75 μm along the gate line 301.
m. The rubbing direction of the substrate is the rubbing direction A304 on the array substrate side and the rubbing direction B on the counter substrate side.
305. Voids 303 formed in the pixel electrode 302
Is the gate line 30 from the center of the source line 300.
1 has a slit shape having a different line width in parallel with 1. At this time, the hole 303 is 10 μm from the edge of the pixel electrode 302.
Within, the line width A306 is 10 μm.
The line width B307 is 6 μm.

A polarizing plate was laminated on the electrode split type panel having the above-mentioned structure with its absorption axis parallel to the rubbing direction. Then, the panel was driven in a normally white mode, and the formation of liquid crystal domains was observed using an optical microscope. In addition, a backlight is attached to the panel, and a wavelength of 54
The panel contrast was measured using a 0 nm filter. As the contrast, a value obtained by dividing the brightness of the white level of the panel by the brightness of the black level was used.

FIG. 4 is a schematic view of a pixel domain observed with the optical microscope. FIG. 4 shows the black level in the normally white mode. At this time, the reverse tilt rolling line 404 occurred at the domain boundary. At this time, the reverse tilt rolling line 404 was generated in the same shape as the hole 403, and the two domains adjacent to each other across the rolling line were extremely stable. Further, since the holes 303 are small, the degree of light leakage due to the holes 303 was small. The contrast of the panel measured by the above method was as high as 115, and the image was good.

As described above, with the above structure, the orientation of the electrode-divided liquid crystal panel is stabilized, the reliability is improved, and the holes 3 are formed.
Since the size of 03 was small, light leakage through the slit was reduced, and a high-contrast display was obtained.

Not limited to the above example, the same effect can be obtained if the line width of the hole 303 is larger than 8 μm and the length is larger than 5 μm.

In the above example, the holes 303 are connected to the source line 3
Although it was created from the central part of 00, it may be created parallel to the gate line 301 from other than the central part of the source line 300 by designing the viewing angle characteristics.

Further, although the panel is driven in the normally white mode in the above example, it may be in the normally black mode.

In the above example, the light shielding layer does not exist in the holes, but this may be provided by using metallic chromium or the like.

The orientation of the liquid crystal may be 90 ° twist nematic alignment other than the above 90 ° splay twist orientation.

Example 2 An electrode split type liquid crystal panel having the same structure as in Example 1 was prepared. FIG. 5 shows a schematic diagram of one pixel.

The holes 503 formed in the pixel electrode 502 are
The pixel electrode 502 has slit shapes with different line widths in the diagonal direction. At this time, the holes 503 become the pixel electrodes 50.
The line width A506 is 6 μm within 15 μm from the end of 2, and the line width B507 is 4 μm in other portions. The shape of the domain at the black level was observed using an optical microscope. Further, the contrast of the panel was measured by the same method as in Example 1.

FIG. 6 is a schematic view of a pixel domain observed with the optical microscope. FIG. 6 shows the black level in the normally white mode. At this time, the reverse tilt rolling line 604 occurred at the domain boundary. At this time, the reverse tilt rolling line is generated in the same shape as the hole 603,
Two domains adjacent to each other across the tilt line were extremely stable. In addition, since the holes 603 are small, the holes 603 are
The degree of light leakage due to was also small. The contrast of the panel measured by the above method was as high as 110, and the image was good.

As described above, with the above structure, the orientation of the electrode-divided liquid crystal panel is stable, and further, since the size of the hole 603 is small, the light leakage of the slit is reduced, and a high contrast display is obtained. .

In the above example, the portion having a large line width of the hole 603 was formed with a length of 15 μm and a line width of 6 μm. However, these numerical values are not limited to the above example, the line width is 6 μm or more and the length is 5 μm.
Similar effects can be obtained if the thickness is at least μm. Also, the line width of the hole 603 in the central portion of the pixel is not limited to 4 μm as described above, and
It should be at least μm.

Although the panel is driven in the normally white mode in the above example, it may be in the normally black mode.

In the above example, the light shielding layer does not exist in the holes, but this may be provided by using metallic chrome or the like.

Example 3 An electrode split type liquid crystal panel having the same structure as in Example 1 was prepared. FIG. 7 shows a schematic diagram of one pixel.

The holes 703 formed in the pixel electrode 702 are
The source line 700 has a rectangular shape parallel to the gate line 701 from the central portion thereof, and further has a triangular protrusion 706 of the same size on the side surface. At this time, holes 7
No. 03 is a regular triangle having a line width of 4 μm and one side of 4 μm, and the triangle is formed at an equal interval of 8 μm. The shape of the domain at the black level was observed using an optical microscope. Further, the contrast of the panel was measured by the same method as in Example 1.

With the above structure, the orientation of the electrode split type liquid crystal panel was extremely stable. Further, since the size of the hole 703 is small, the light leakage of the slit is reduced and the contrast is 1
It was as high as 05. As described above, with the above-described configuration, it was possible to obtain a highly reliable, high-contrast and good display.

The size of the line width of the holes 703 and the size of the triangle are not limited to the above values. Further, in the above example, the pitches of the triangles are all equally spaced, but this may be different depending on the location.

In the above example, the holes 703 are formed parallel to the gate lines, but they may be formed in the diagonal direction of the pixel electrodes 702.

In the above example, the protrusion 706 has a triangular shape, but the shape of the protrusion 706 may be semicircular or polygonal.

Example 4 An electrode split type liquid crystal panel having the same structure as in Example 1 was prepared. FIG. 8 shows a schematic diagram of one pixel.

The holes 803 formed in the pixel electrode 802 are
It has a slit shape in which triangular protrusions 806 having different sizes are provided in parallel with the gate line 801 from the center of the source line 800. At this time, the hole 803 has a line width of 4 μm, triangles within 20 μm from the edge of the pixel are regular triangles with a side of 4 μm, and in other regions, regular triangles with a side of 2 μm are created at regular intervals of 8 μm. did. The shape of the domain at the black level was observed using an optical microscope. Further, the contrast of the panel was measured by the same method as in Example 1.

With the above structure, the orientation of the electrode division type liquid crystal panel was extremely stable. Further, since the size of the hole 803 is small, the light leakage of the slit is reduced, and the contrast is 1
It was as high as 02. As described above, with the above-described configuration, it was possible to obtain a highly reliable, high-contrast and good display.

The size of the line width of the holes 803 and the size of the triangle are not limited to the above values, and may be values larger than those in the above example.
Further, in the above example, the pitches of the triangles are all equally spaced, but this may be different depending on the location.

In the above example, the hole 803 is formed in the gate line 8
However, it may be formed in the diagonal direction of the pixel electrode 802.

In the above example, the projection 806 is triangular, but the shape of the projection 806 may be semicircular or polygonal.

Example 5 An electrode split type liquid crystal panel having the same structure as in Example 1 was prepared. FIG. 9 shows a schematic diagram of one pixel.

A large number of circular holes 903 are formed in the pixel electrode 902.
Was formed linearly. The diameter of the hole 903 was 8 μm within 20 μm from the edge of the pixel, and otherwise the diameter was 4 μm. The pitch of holes is 1 within 20 μm from the edge of the pixel.
The thickness was 0 μm, and the others were 6 μm, and they were formed at equal intervals. The shape of the domain at the black level was observed using an optical microscope. Further, the contrast of the panel was measured by the same method as in Example 1.

With the above structure, the orientation of the electrode split type liquid crystal panel was stabilized. Further, since the total area of the holes 903 is small, the contrast was as high as 110. As described above, with the above-described configuration, it was possible to obtain a highly reliable, high-contrast and good display.

The diameter of the hole 903 is not limited to the above value, but may be any value larger than the above example. Also, the pitch of the holes 903 is not limited to the above value.

In the above example, the circular hole 903 is formed linearly in parallel with the gate line 901, but it may be formed in the diagonal direction of the pixel electrode 902. Further, instead of changing the diameter of the holes 903, circular holes 903 having the same size may be arranged by changing the density created depending on the location in the pixel 902. In this case, a large number of holes 903 are arranged near the edge of the pixel 902, and the holes 903 are integrated.
Area needs to be increased.

Although the holes 903 are circular in the above example, the same effect can be obtained by using generally polygonal holes.

(Comparative Example 1) An electrode split type liquid crystal panel having the same structure as in Example 1 was prepared. At this time, the holes formed in the pixel electrode were formed in a rectangular slit shape having a line width of 11 μm. FIG. 10 shows a schematic diagram of one pixel at the black level in the normally white mode. The reverse tilt roll line 926 occurred at the domain boundary. At this time, the reverse tilt rolling line 926 is generated in the same shape as the hole 923, and the adjacent two
The orientation of the two domains was very good. However, since the area occupied by the holes 923 in the pixel 922 is large, the degree of light leakage due to the holes 923 was large.

The contrast of the panel measured by the same method as in Example 1 was very low as 60, and good image display was not obtained. (Comparative Example 2) Electrode split type liquid crystal with the same configuration as in Example 1 Created a panel. At this time, the holes formed in the pixel electrodes were formed into rectangular slits having a line width of 4 μm. FIG.
A schematic diagram of one pixel at the black level in the normally white mode is shown in FIG. Reverse tilt tilt line 9 at the domain boundary
56 occurred. At this time, the reverse tilt roll line 956 is
A part of the line was generated in the same shape as the hole 953, but the line was off the hole 953 near the edge of the pixel 952. For this reason, the orientation of two adjacent domains was unstable, and sufficient reliability could not be obtained for the panel.

[0077]

As is apparent from the above description,
In the electrode-divided liquid crystal display device of the present invention, in the electrode-divided liquid crystal display device, the shape of the holes formed in the pixel electrode is changed in the pixel electrode to enhance the alignment stability of the liquid crystal and improve the reliability. At the same time, high contrast image display is realized.

The area of the liquid crystal in which the orientation of the liquid crystal is likely to be unstable increases the stability by increasing the area of the pores, and the area where the orientation is relatively stable reduces the area of the pores to increase the contrast. By designing the holes so that an even better image display can be obtained.

The method of improving the contrast of the panel by changing the shape of the holes in the pixel does not require a new mask, and can be formed with the same procedure and cost as the conventional electrode split type panel. High cost merit.

When the electrode split type panel is used in the normally white mode, the improvement of the contrast of the panel is one of the biggest problems, but the present invention improves the image display performance of the electrode split type panel. Is extremely large.

[Brief description of drawings]

FIG. 1 is a sectional view of an electrode split type panel.

FIG. 2 is a sectional view of an electrode split type liquid crystal display device according to a first embodiment of the present invention.

FIG. 3 is a schematic diagram of a pixel of the electrode division type liquid crystal display device of Example 1 of the present invention.

FIG. 4 is a plan view of a pixel when driving the panel of the electrode division type liquid crystal display device according to the first embodiment of the present invention.

FIG. 5 is a schematic diagram of a pixel of an electrode division type liquid crystal display device according to a second embodiment of the present invention.

FIG. 6 is a plan view of a pixel when driving a panel of an electrode division type liquid crystal display device according to a second embodiment of the present invention.

FIG. 7 is a schematic diagram of a pixel of an electrode division type liquid crystal display device according to a third embodiment of the present invention.

FIG. 8 is a schematic diagram of a pixel of an electrode division type liquid crystal display device according to a fourth embodiment of the present invention.

FIG. 9 is a schematic diagram of a pixel of an electrode split type liquid crystal display device according to a fifth embodiment of the present invention.

FIG. 10 is a plan view of a pixel when driving the panel of the electrode division type liquid crystal display device of Comparative Example 1.

FIG. 11 is a plan view of a pixel when driving the panel of the electrode division type liquid crystal display device of Comparative Example 2.

[Explanation of symbols]

300, 400, 500, 600, 700, 800, 9
00 source lines 301, 401, 501, 601, 701, 801, 9
01 Gate line 302, 402, 502, 602, 702, 802, 9
02 Pixel electrodes 303, 403, 503, 603, 703, 803, 9
03 holes 304, 504, 704, 804, 904 rubbing direction A 305, 505, 705, 805, 905 rubbing direction B 404, 604 reverse tilt tilt line 306 line width A 307 line width B

Claims (10)

[Claims] 1. A liquid crystal display device comprising as its components a liquid crystal panel including a substrate including a pixel electrode having a hole in at least a part of a region, a substrate including a transparent electrode, and a liquid crystal panel as a component. The electrode split type liquid crystal display device, wherein the shape of the formed hole has different portions within the pixel electrode. 2. A region of the pixel electrode in which the orientation of the liquid crystal is likely to be unstable has a large area of pores to improve stability, and a region in which the orientation of the liquid crystal is relatively stable has a small area of pores. 2. The electrode split type liquid crystal display device according to claim 1, wherein the shape of the holes is configured so as to increase the contrast. 3. A liquid crystal display device comprising as components a liquid crystal panel including a substrate including a pixel electrode having substantially slit-shaped holes in at least a part of a region, a substrate including a transparent electrode, and a liquid crystal. , L1> L2, where L1 is the hole width near the pixel end of the pixel electrode and L2 is the hole width near the center of the pixel electrode. Liquid crystal display device. 4. The electrode split type liquid crystal display device according to claim 3, wherein the holes are present in a direction substantially along at least one of the diagonal lines of the pixel electrodes. 5. The electrode division type liquid crystal display device according to claim 3, wherein the holes are present in a direction substantially parallel to one of the pixel sides of the pixel electrode. 6. The electrode split type liquid crystal display device according to claim 5, wherein the hole is present substantially in the center of the pixel side of the pixel electrode. 7. An electrode-splitting type liquid crystal including, as constituent elements, a liquid crystal panel including a substrate including a pixel electrode having a substantially slit-shaped hole in at least a part of a region, a substrate including a transparent electrode, and a liquid crystal. In the display device, the electrode split type liquid crystal display device, wherein the hole has a shape having at least one protrusion on a long side of the slit. 8. An electrode-splitting type liquid crystal including, as constituent elements, a liquid crystal panel including a substrate including a pixel electrode having substantially slit-shaped holes in at least a part of a region, a substrate including a transparent electrode, and a liquid crystal. In the display device, the hole has a shape having a protrusion on the long side of the slit, the area of the protrusion near the pixel end of the pixel electrode is S1, and the area of the protrusion near the center of the pixel electrode is S1. When S2, S
An electrode division type liquid crystal display device, characterized in that a relation of 1> S2 is established. 9. The electrode split type liquid crystal display device according to claim 7, wherein the shape of the protrusion is a polygon or a circle. 10. An electrode division type liquid crystal display device comprising as its components a liquid crystal panel including a substrate including a pixel electrode having a plurality of holes in at least a part of a region, a substrate including a transparent electrode, and liquid crystal. The electrode split type liquid crystal display device, wherein the shape of the holes is substantially circular or polygonal, and the areas of the circular or polygonal holes are different in the area of the pixel electrode.