JP2006113205A - Liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inject a liquid crystal material in an empty cell in a short period of time even though projecting patterns are utilized for domain division. <P>SOLUTION: In the liquid crystal display device 1, a plurality of projecting patterns 36 are provided in positions corresponding to a plurality of pixel electrodes 23 on at least one of opposed surfaces of an array substrate and a counter substrate. Each projecting pattern 36 has a structure wherein a ridge-shaped projecting part BP3 extending in a third direction D3 crossing a first direction D1 and a second direction D2 and a ridge-shaped projecting part BP4 extending in a fourth direction D4 crossing the first or the third direction D1 or D3 are arranged in the second direction D2 and each projecting pattern 36 has a shape and an azimuth equal to those of a pattern obtained by rotating a projecting pattern 36 adjacent thereto in the second direction D2 around an axis orthogonal to the first direction D1 and the second direction D2 by 180°. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a liquid crystal display device.

  According to a VA (Vertically Aligned) mode liquid crystal display device using a liquid crystal material having a negative dielectric anisotropy and a vertical alignment film, a faster response speed than a TN (Twisted Nematic) mode liquid crystal display device. Can be realized. In addition, the VA mode liquid crystal display device does not require a rubbing process that causes defects such as electrostatic breakdown. Among them, a VA mode (hereinafter referred to as MVA mode) liquid crystal display device adopting a multi-domain method is particularly attracting attention because a wide viewing angle is relatively easy.

  In the MVA mode, each pixel region in the liquid crystal layer is divided into a plurality of domains having different tilt directions of liquid crystal molecules by forming an electric field gradient in the liquid crystal layer and / or providing protrusions on the substrate surface. To do. For example, a slit is provided in at least one of the pixel electrode and the counter electrode, and the direction of the electric field is made different for each domain. Alternatively, a convex pattern composed of hook-shaped convex portions is provided on at least one of the opposing surfaces of the array substrate and the counter substrate. Alternatively, a slit and a convex pattern are combined.

  By the way, these convex patterns prevent the liquid crystal material from being injected into the empty cells. Therefore, when a convex pattern is used for domain division, it takes a long time to inject a liquid crystal material into an empty cell, and it is difficult to realize high productivity.

  Further, the time required for injecting the liquid crystal material into the empty cell and the injection time are affected by variations in the shape and composition of each component and variations in the injection conditions such as temperature. When the injection time is long, the injection time varies greatly due to these variations. Therefore, when a convex pattern is used for domain division, an injection failure is likely to occur.

  An object of the present invention is to enable a liquid crystal material to be injected into an empty cell in a short time while using a convex pattern for domain division.

  According to a first aspect of the present invention, an array substrate including a first substrate and a plurality of pixel electrodes arranged in first and second directions intersecting each other on one main surface thereof, and the plurality of pixel electrodes face each other. A counter substrate including a second substrate and a counter electrode provided on a surface facing the array substrate; and interposed between the array substrate and the counter substrate and surrounding the plurality of pixel electrodes. An adhesive layer, and the adhesive layer includes an empty cell that forms an injection port that communicates an internal space surrounded by the array substrate, the counter substrate, and the adhesive layer with an external space, and the internal space. A liquid crystal material having a negative dielectric anisotropy, and a sealing body that closes the injection port; and a surface of the array substrate facing the counter substrate and a surface of the counter substrate facing the array substrate At least one of the surfaces has the plurality of pixel electrodes. A plurality of convex patterns are respectively provided at positions corresponding to, and each of the plurality of convex patterns includes a hook-shaped convex portion extending in a third direction intersecting with the first and second directions, and the first to first And having a structure in which hook-shaped protrusions extending in a fourth direction intersecting with three directions are arranged in the second direction, and each of the plurality of convex patterns includes the convex pattern adjacent to the second direction. A liquid crystal display device having the same shape and orientation as a pattern obtained by rotating 180 ° around an axis orthogonal to the first and second directions is provided.

  According to a second aspect of the present invention, an array substrate including a first substrate and a plurality of pixel electrodes arranged in first and second directions intersecting each other on one main surface thereof, and the plurality of pixel electrodes face each other. A counter substrate including a second substrate and a counter electrode provided on a surface facing the array substrate; and interposed between the array substrate and the counter substrate and surrounding the plurality of pixel electrodes. An adhesive layer, and the adhesive layer includes an empty cell that forms an injection port that communicates an internal space surrounded by the array substrate, the counter substrate, and the adhesive layer with an external space, and the internal space. A liquid crystal material having a negative dielectric anisotropy, and a sealing body that closes the injection port, and each of the plurality of pixel electrodes is provided with a plurality of slit patterns, Each of the first and first A slit extending in a third direction intersecting the direction and a slit extending in a fourth direction intersecting the first to third directions are arranged in the second direction, and the slit patterns Each has the same shape and orientation as the pattern obtained by rotating the slit pattern adjacent to the second direction by 180 ° around an axis orthogonal to the first and second directions, and A plurality of convex patterns are provided on the surface facing the array substrate at positions corresponding to the plurality of pixel electrodes, and each of the plurality of convex patterns includes a hook-shaped convex portion extending in the third direction; A plurality of convex patterns extending in the fourth direction are arranged in the second direction, and each of the plurality of convex patterns has the convex pattern adjacent to the second direction around the axis. so There is provided a liquid crystal display device characterized by having the same shape and orientation as the pattern obtained by rotating 180 °.

  According to the present invention, it is possible to inject a liquid crystal material into an empty cell in a short time while using a convex pattern for domain division.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same referential mark is attached | subjected to the component which exhibits the same or similar function, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a plan view schematically showing a liquid crystal display device according to one embodiment of the present invention. FIG. 2 is an enlarged plan view showing the liquid crystal display device of FIG. FIG. 3 is a plan view showing the liquid crystal display device of FIG. 1 further enlarged. 4 is a cross-sectional view taken along line IV-IV of the liquid crystal display device of FIG. FIG. 5 is a simplified cross-sectional view of the liquid crystal display device of FIG. 6 is a plan view showing an array substrate of the liquid crystal display device of FIG. FIG. 7 is a plan view showing a counter substrate of the liquid crystal display device of FIG.

  1 to 3 show a liquid crystal display device viewed from the counter substrate side. 6 illustrates the array substrate viewed from the counter substrate side, and FIG. 7 illustrates the counter substrate viewed from the array substrate side.

  In these drawings, some components are omitted for simplification. For example, in FIG. 2, the pixel electrode and the dielectric layer for forming the ridge-shaped convex portion are drawn, and other components are omitted. In FIG. 3, the pixel electrode, the ridge-shaped protrusions, and the liquid crystal molecules are drawn, and other components are omitted. In FIG. 4, the previous dielectric layer and slits provided in the common electrode are omitted, and in FIG. 5, switching elements, color filters, spacers, polarizing plates, and the like are omitted. In FIG. 6, the alignment film, the spacer, the color filter, the switching element, and the like are omitted, and in FIG. 7, the alignment film is omitted.

  The liquid crystal display device 1 is an MVA type liquid crystal display device. As shown in FIGS. 1 and 4, the liquid crystal display device 1 includes an array substrate 2 and a counter substrate 3. The array substrate 2 and the counter substrate 3 face each other with a slight gap. The structures of the array substrate 2 and the counter substrate 3 will be described in detail later.

  As shown in FIG. 4, spacers 8 are interposed between the array substrate 2 and the counter substrate 3. Here, as an example, columnar spacers are used as the spacers 8 and these columnar spacers 8 are formed on the array substrate 2. These spacers 8 serve to keep the distance between the array substrate 2 and the counter substrate 3 constant.

  As shown in FIG. 4, an adhesive layer 4 is further interposed between the array substrate 2 and the counter substrate 3. The adhesive layer 4 is formed using an adhesive such as a thermosetting resin, for example. This adhesive layer 4 has a frame shape as shown in FIG. The adhesive layer 4 bonds the array substrate 2 and the counter substrate 3 to each other, and forms an empty cell together with the array substrate 2 and the counter substrate 3.

  As shown in FIG. 1, the frame formed by the adhesive layer 4 is open on one end face side of the empty cell. This opening is used as an injection port that communicates the internal space surrounded by the array substrate 2, the counter substrate 3, and the adhesive layer 4 with the external space.

  A transfer electrode (not shown) is interposed between the array substrate 2 and the counter substrate 3 and outside the frame formed by the adhesive layer 4. The array substrate 2 and the counter substrate 3 are electrically connected by this transfer electrode.

  The internal space of the empty cell is filled with the liquid crystal material 5 as shown in FIG. The liquid crystal material 5 forms a liquid crystal layer. In the liquid crystal display device 1, a liquid crystal material having a negative dielectric anisotropy, particularly a nematic liquid crystal having a negative dielectric anisotropy, is used as the liquid crystal material 5. The liquid crystal material is injected into the empty cell by using an injection method such as a dip type or a dispenser type, for example.

  As shown in FIG. 1, the empty cell inlet is closed by a sealing body 6. The sealing body 6 is formed, for example, by dispensing an adhesive such as an ultraviolet curable resin at the injection port and curing it.

  A polarizing plate 7 is attached to the outer surface of the array substrate 2. A polarizing plate 7 is also attached to the outer surface of the counter substrate 3.

  The liquid crystal display device 1 usually further includes a backlight that illuminates the outer surface of the array substrate 2.

Next, the structure of the array substrate 2 and the counter substrate 3 will be described.
As shown in FIG. 4, the array substrate 2 includes an insulating substrate 20 having optical transparency such as a glass substrate as a first substrate. On one main surface of the insulating substrate 20, wiring, an interlayer insulating film, a switching element 21 and the like are formed. On them, a color filter 22, a pixel electrode 23, a columnar spacer 8, and an alignment film 24 are sequentially formed. A peripheral light shielding layer (or frame) 25 is formed around the color filter 22.

  Wirings formed on the insulating substrate 20 are gate lines, signal lines, auxiliary capacitance lines, and the like made of aluminum, molybdenum, copper, or the like. The switching element 21 is, for example, a TFT having amorphous silicon or polysilicon as a semiconductor layer and aluminum, molybdenum, chromium, copper, tantalum, or the like as a metal layer, and includes wiring such as gate lines and signal lines, and pixel electrodes. 23. With such a configuration, the array substrate 2 can selectively apply a voltage to a desired pixel electrode 23.

  The color filter 22 includes blue, green, and red colored layers 22B, 22G, and 22R. The color filter 22 is provided with a contact hole, and the pixel electrode 23 is connected to the switching element 21 through the contact hole. The colored layers 22B, 22G, and 22R can be formed using a photosensitive resin containing a colored dye or a colored pigment.

  As the material of the pixel electrode 23, for example, a transparent conductive material such as ITO (Indium Tin Oxide) can be used. The pixel electrode 23 can be formed by, for example, forming a thin film by a sputtering method or the like and then patterning the thin film using a photolithography technique and an etching technique.

  The pixel electrodes 23 are arranged in first and second directions that are substantially parallel to the main surface of the insulating substrate 20 and intersect each other. In this example, the pixel electrodes 23 are arranged in a first direction D1 substantially parallel to an end face provided with an empty cell injection port and a second direction D2 substantially perpendicular to the end face. The pixel electrodes 23 adjacent to each other in the first direction D1 form a slit SLT2 whose longitudinal direction is substantially parallel to the second direction D2. Further, the pixel electrodes 23 adjacent to each other in the second direction D2 form a slit SLT1 between which the longitudinal direction is substantially parallel to the first direction D1.

  As shown in FIGS. 2, 3, and 6, each pixel electrode 23 is provided with slits SLT1, SLT3, and SLT4 in a rectangle having a side parallel to the first direction D1 and a side parallel to the second direction D2. It has a different shape. The slits SLT1, SLT3, and SLT4 provided in each pixel electrode 23 form a slit pattern.

  The longitudinal direction of the slit SLT3 is parallel to a third direction D3 that intersects the first direction D1 and the second direction D2. In this example, the third direction D3 forms an angle of about 45 ° with respect to the first direction D1. The longitudinal direction of the slit SLT4 is parallel to a fourth direction D4 that intersects the first direction D1, the second direction D2, and the third direction D3. In this example, the fourth direction D4 is substantially orthogonal to the third direction D3.

  As shown in FIGS. 2, 3 and 6, the pixel electrodes 23 adjacent in the first direction D1 have the same shape and orientation. Further, as shown in FIG. 2, one of the pixel electrodes 23 adjacent in the second direction D2 is obtained by rotating the other by 180 ° around an axis orthogonal to the first direction D1 and the second direction D2. The shape and orientation are the same.

  The alignment film 24 formed on the pixel electrode 23 is composed of a thin film made of a transparent resin such as polyimide. The alignment film 24 is given a vertical alignment without being rubbed.

  The peripheral light shielding layer 25 surrounds the color filter 22. The peripheral light shielding layer 25 can be formed using a photosensitive resin containing a coloring dye or a coloring pigment.

  As shown in FIGS. 4 and 5, the counter substrate 3 includes a light-transmissive insulating substrate 30 such as a glass substrate as a second substrate. As shown in FIG. 5, a common electrode 33, a patterned dielectric layer 36, and an alignment film 34 are sequentially formed on one main surface of the insulating substrate 30.

  The common electrode 33 is formed as a continuous film facing all the pixel electrodes 23. As a material of the pixel electrode 23, for example, a transparent conductive material such as ITO can be used.

  The alignment film 34 is composed of a thin film made of a transparent resin such as polyimide. The alignment film 34 is given a vertical alignment without being rubbed.

  In this example, the dielectric layer 36 is patterned into the shape shown in FIGS. The patterned dielectric layer 36 generates convex patterns including the ridge-shaped convex portions PRT1 to PRT4 shown in FIGS. 3 and 4 at each position corresponding to the pixel electrode 23 on the surface of the alignment film 34. .

  Each portion of the dielectric layer 36 corresponding to the pixel electrode 23 includes strip portions BP1 to BP4 shown in FIG. The longitudinal directions of the strips BP1 to BP4 are substantially parallel to the first direction D1 to the fourth direction D4, respectively. The saddle-like convex portions PRT1 to PRT4 are convex portions formed by the strip-like portions BP1 to BP4 on the surface of the alignment film 34, respectively.

  As shown in FIG. 3, the hook-shaped protrusion PRT1 has a longitudinal direction parallel to the longitudinal direction of the slit SL1. As shown in FIG. 3, when the liquid crystal display device 1 is observed from a direction perpendicular to the main surface, the hook-shaped protrusion PRT1 overlaps with a portion of the outline of the pixel electrode 23 where the slit SLT1 is formed. Yes.

  As shown in FIG. 3, the hook-shaped protrusion PRT2 has a longitudinal direction parallel to the longitudinal direction of the slit SL2. As shown in FIG. 3, when the liquid crystal display device 1 is observed from a direction perpendicular to the main surface, the hook-shaped protrusion PRT2 overlaps with a portion of the outline of the pixel electrode 23 where the slit SLT2 is formed. Yes.

  As shown in FIG. 3, the hook-shaped convex part PRT3 has a longitudinal direction parallel to the longitudinal direction of the slit SL3. As shown in FIGS. 3 and 5, the hook-shaped convex part PRT3 faces a region between the slits SLT3 adjacent to the direction intersecting the third direction D3, for example, the fourth direction D4.

  As shown in FIG. 3, the hook-shaped convex part PRT4 has a longitudinal direction parallel to the longitudinal direction of the slit SL4. As shown in FIG. 3, the hook-shaped protrusion PRT4 faces a region intersecting the fourth direction D4, for example, the region between the slits SLT4 adjacent to the third direction D3.

  As shown in FIG. 3, in each convex pattern, the ridge-shaped protrusion PRT3 and the ridge-shaped protrusion PRT4 are arranged in the second direction D2. In other words, in the liquid crystal display device 1, each pixel is divided into two parts arranged in the second direction D2, and the hook-like convex part PRT3 is arranged on one side, and the hook-like convex part PRT4 is arranged on the other side. ing.

  Further, as can be seen from the dielectric layer 36 shown in FIG. 3, each convex pattern has a convex pattern adjacent to it in the second direction D2 180 around the axis orthogonal to the first direction D1 and the second direction D2. The pattern and shape and orientation obtained by rotating are the same. Further, the convex patterns adjacent in the first direction D1 have the same shape and orientation.

  The slits SLT <b> 1 to SLT <b> 4 and the ridge-shaped convex part PRT <b> 4 control the alignment of the liquid crystal molecules LC included in the liquid crystal material 5 as follows.

  When a first voltage having a small absolute value is applied between the pixel electrode 23 and the common electrode 33, an electric field is formed in the liquid crystal material 5. Since the liquid crystal material 5 has a negative dielectric anisotropy, a force is applied to the liquid crystal molecules LC to align them perpendicularly to the lines of electric force.

  In the upper part of the slits SLT1 to SLT4, the lines of electric force are tilted without being perpendicular to the main surfaces of the pixel electrode 23 and the common electrode 33. For example, in the upper part of the slit SLT3, the electric lines of force are inclined as shown by the broken lines in FIG. Therefore, in the upper part of the slits SLT1 to SLT4, a force for aligning the liquid crystal molecules LC perpendicularly to the oblique lines of electric force is applied. That is, for example, a force for tilting the liquid crystal molecules LC as shown in FIG. 5 is applied to the liquid crystal molecules LC.

  On the other hand, since the alignment films 24 and 34 are vertical alignment films, the alignment films 24 and 34 attempt to align the liquid crystal molecules LC perpendicularly to their film surfaces. For this reason, the alignment film 34 tends to tilt the liquid crystal molecules LC as shown in FIG.

  As a result, each pixel region corresponding to the pixel electrode 23 in the liquid crystal layer has different tilt directions of the liquid crystal molecules LC with the slits SLT1 to SLT4 and the ridge-shaped protrusions PRT1 to PRT4 as boundaries, as shown in FIG. Divided into multiple domains. In this example, in each pixel region, a total of four types of domains having different tilt directions of the liquid crystal molecules LC are formed.

  When the voltage applied between the pixel electrode 23 and the common electrode 33 is a second voltage having a larger absolute value compared to the first voltage, the liquid crystal molecules LC maintain their tilt directions while maintaining their molecular axes. And the angle formed by the main surfaces of the pixel electrode 23 and the common electrode 33 are reduced. In the liquid crystal display device 1, display is performed by using the change in the refractive index of the liquid crystal layer generated thereby.

  Now, in this embodiment, the above structure is adopted for the liquid crystal display device 1. Such a liquid crystal display device 1 is easier to inject liquid crystal than the liquid crystal display device of FIG.

  FIG. 8 is a plan view schematically showing the liquid crystal display device 1 according to the comparative example. This liquid crystal display device 1 is the same as the liquid crystal shown in FIGS. 1 to 5 except that the shape and orientation of the pixel electrodes 23 adjacent in the second direction are the same and the shape and orientation of the convex pattern adjacent in the second direction are the same. The display device 1 has the same structure.

  As explained above, the convex pattern prevents the injection of the liquid crystal material 5 into the empty cell. Therefore, when a convex pattern is used for domain division, it takes a long time to inject the liquid crystal material 5 into the empty cell, and it is difficult to realize high productivity.

  At the time of injection, the flow path in which the liquid crystal material 5 flows plays a role in the band-like part BP3 adjacent in the first direction and the band-like part BP4 adjacent in the first direction. The shape of this flow path has a great influence on the injection time. Specifically, when the flow path includes more bent portions, a longer time is required for injecting the liquid crystal material 5 into the empty cell.

  In the liquid crystal display device 1 of FIG. 8, the strip portion BP3 and the strip portion BP4 of the dielectric layer 36 are adjacent to each other with each boundary between pixels adjacent in the second direction D2. On the other hand, in the liquid crystal display device 1 according to this aspect, as shown in FIG. 2, the strips BP3 of the dielectric layer 36 are adjacent to each other across the boundary between adjacent pixels in the second direction D2. The strips BP4 are adjacent to each other.

  That is, the liquid crystal display device 1 according to this aspect has fewer bent portions of the previous flow path than the liquid crystal display device 1 of FIG. Therefore, according to this aspect, the liquid crystal material 5 can be injected into the empty cell in a shorter time as compared with the case where the structure of FIG. 8 is adopted in the liquid crystal display device 1. That is, according to this aspect, the dispersion of the injection time hardly occurs, and the injection failure caused by this can be suppressed.

  In this embodiment, the slits SLT1 to SLT4 are provided in the pixel electrode 23 and the ridge-shaped protrusions PRT1 to PRT4 are formed on the surface of the counter substrate 2 facing the array substrate 3, but the slits SLT1 to SLT4 are formed in the common electrode 33. In addition to the provision, the ridge-shaped protrusions PRT1 to PRT4 may be formed on the surface of the array substrate 3 facing the counter substrate 2. Alternatively, as part of the liquid crystal display device 1, the slits SLT 1 to SLT 4 are provided in the pixel electrode 23, and the ridge-shaped protrusions PRT 1 to PRT 4 are formed on the surface of the counter substrate 2 facing the array substrate 3. In another part, the slits SLT1 to SLT4 may be provided in the common electrode 33, and the ridge-shaped protrusions PRT1 to PRT4 may be formed on the surface of the array substrate 3 facing the counter substrate 2.

  In this embodiment, the color filter 22 is disposed between the insulating substrate 20 and the pixel electrode 23, but the color filter 22 may be disposed between the insulating substrate 30 and the common electrode 33. In this embodiment, a columnar spacer is used as the spacer 8, but a granular spacer may be used as the spacer 8.

Examples of the present invention will be described below.
(Example)
In this example, the liquid crystal display device 1 shown in FIGS. 1 to 5 was manufactured by the method described below.

  First, film formation and patterning were repeated in the same manner as a normal array substrate formation process, and various wirings, TFTs 21 and the like were formed on the glass substrate 20. Next, a color filter 22 was formed by a conventional method on the surface of the glass substrate 20 on which the TFTs 21 and the like were formed.

  Next, ITO was sputtered on the color filter 22 to a thickness of about 0.1 μm through a mask having a predetermined pattern. Thereafter, a resist pattern was formed on the ITO film, and the exposed portion of the ITO film was etched using the resist pattern as a mask. As described above, the pixel electrode 23 shown in FIGS. 2 to 6 was formed. Here, the distance between the pixel electrodes 23 adjacent in the first direction is 6 μm. The widths of the slits SLT1, SLT3, and SLT4 provided in the pixel electrode 23 were 10 μm.

  Next, the photosensitive resin containing a black pigment was apply | coated to the surface in which the pixel electrode 23 of the glass substrate 20 was formed using the spinner. After drying this coating film, pattern exposure using ultraviolet rays, development using an aqueous alkaline solution, and baking were sequentially performed. Thereby, the spacer 8 and the peripheral light shielding layer 25 were obtained.

  Thereafter, a thermosetting resin was applied to the entire surface of the glass substrate 20 on which the pixel electrode 23 was formed, and this coating film was baked to form an alignment film 24 having a thickness of 70 nm showing vertical alignment. The array substrate 2 was produced as described above.

  Next, an ITO film was formed as a common electrode 33 on one main surface of a separately prepared glass substrate 30 by a sputtering method. Next, a photosensitive resin was applied onto the common electrode 33 using a spinner. After drying this coating film, pattern exposure using ultraviolet rays, development using an aqueous alkaline solution, and baking were sequentially performed. Thereby, the dielectric layer 36 was obtained. Here, the width of the strips BP1 to BP4 is 8 μm.

  Subsequently, an alignment film 34 was formed on the surface of the glass substrate 30 on which the dielectric layer 36 was formed by the same method as described for the array substrate 2. The counter substrate 3 was produced as described above.

  Next, the active matrix substrate 2 and the peripheral portion of the counter surface of the counter substrate 3 were bonded together using an epoxy thermosetting resin 4 to form an empty cell. A liquid crystal material 5 was injected into this empty cell by a dip method. This injection took about 42 hours.

  Thereafter, the injection port was closed with an ultraviolet curable resin 6, and the polarizing plate 7 was attached to the outer surfaces of the array substrate 2 and the counter substrate 3. As described above, the liquid crystal display device 1 shown in FIGS. 1 to 5 was completed.

  Next, the characteristics of the liquid crystal display device 1 were evaluated. As a result, regarding the viewing angle characteristics, a contrast of 10: 1 or more was obtained in a horizontal angle range of 170 °. In other words, very good viewing angle characteristics could be realized. This is considered to be due to the improved domain objectivity by making the slit pattern provided on the pixel electrode 23 and the convex pattern formed by the dielectric layer 36 into the shape shown in FIG. Further, it was confirmed that the liquid crystal display device 1 was sufficiently excellent with respect to other characteristics.

(Comparative example)
In this example, the liquid crystal display device 1 was manufactured by the same method as described in the above example except that the pixel electrode 23 and the dielectric layer 36 were formed in the shape shown in FIG. In this example, it took about 50 hours to inject the liquid crystal material 5 into the empty cell.

  The liquid crystal display device 1 was also evaluated for characteristics similar to those performed in the above examples. As a result, regarding the viewing angle characteristics, a contrast of 10: 1 or more was obtained in a horizontal angle range of 160 °. That is, this liquid crystal display device 1 was inferior in viewing angle characteristics as compared with the liquid crystal display device 1 according to the above example.

1 is a plan view schematically showing a liquid crystal display device according to one embodiment of the present invention. FIG. 2 is an enlarged plan view showing the liquid crystal display device of FIG. 1. FIG. 2 is an enlarged plan view showing the liquid crystal display device of FIG. 1. FIG. 4 is a cross-sectional view taken along line IV-IV of the liquid crystal display device of FIG. 1. FIG. 2 is a cross-sectional view illustrating the liquid crystal display device of FIG. 1 in a simplified manner. FIG. 2 is a plan view showing an array substrate of the liquid crystal display device of FIG. 1. FIG. 2 is a plan view showing a counter substrate of the liquid crystal display device of FIG. 1. The top view which shows schematically the liquid crystal display device 1 which concerns on a comparative example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display device, 2 ... Array substrate, 3 ... Counter substrate, 4 ... Adhesive layer, 5 ... Liquid crystal material, 6 ... Sealing body, 7 ... Polarizing plate, 8 ... Spacer, 20 ... 1st board | substrate, 21 ... Switching element, 22 ... color filter, 22B ... colored layer, 22G ... colored layer, 22R ... colored layer, 23 ... pixel electrode, 24 ... alignment film, 25 ... peripheral light shielding layer, 30 ... second substrate, 33 ... common electrode, 34 ... Alignment film, 36 ... Dielectric layer, BP1 ... Band-shaped portion, BP2 ... Band-shaped portion, BP3 ... Band-shaped portion, BP4 ... Band-shaped portion, D1 ... First direction, D2 ... Second direction, D3 ... Third direction, D4 ... 4th direction, LC ... liquid crystal molecule, PRT1 ... bowl-like convex part, PRT2 ... bowl-like convex part, PRT3 ... bowl-like convex part, PRT4 ... bowl-like convex part, SLT1 ... slit, SLT2 ... slit, SLT3 ... slit, SLT4 ... Slit.

Claims (5)

An array substrate including a first substrate and a plurality of pixel electrodes arranged in first and second directions intersecting each other on one main surface thereof, a second substrate facing the plurality of pixel electrodes, and the array substrate A counter substrate including a counter electrode provided on the counter surface, and an adhesive layer interposed between the array substrate and the counter substrate and surrounding the plurality of pixel electrodes. The agent layer is an empty cell that forms an injection port that communicates an internal space surrounded by the array substrate, the counter substrate, and the adhesive layer with an external space;
A liquid crystal material having a negative dielectric anisotropy filling the internal space;
Comprising a sealing body closing the injection port,
A plurality of convex patterns are respectively provided at positions corresponding to the plurality of pixel electrodes on at least one of a surface of the array substrate facing the counter substrate and a surface of the counter substrate facing the array substrate,
Each of the plurality of convex patterns includes a hook-shaped protrusion extending in a third direction intersecting the first and second directions, and a hook-shaped protrusion extending in a fourth direction intersecting the first to third directions. And a portion arranged in the second direction,
Each of the plurality of convex patterns has the same shape and orientation as the pattern obtained by rotating the convex pattern adjacent thereto in the second direction by 180 ° around an axis orthogonal to the first and second directions. A liquid crystal display device characterized by the above.   The liquid crystal display device according to claim 1, wherein the plurality of convex patterns adjacent to each other in the first direction have the same shape and orientation.   The liquid crystal display device according to claim 1, wherein the empty cell has an end face substantially orthogonal to the second direction, and the injection port is provided on the end face.   The first and second directions are substantially orthogonal to each other, the third and fourth directions are substantially orthogonal to each other, and the third direction forms an angle of approximately 45 ° with respect to the first direction. The liquid crystal display device according to claim 1. An array substrate including a first substrate and a plurality of pixel electrodes arranged in first and second directions intersecting each other on one main surface thereof, a second substrate facing the plurality of pixel electrodes, and the array substrate A counter substrate including a counter electrode provided on the counter surface, and an adhesive layer interposed between the array substrate and the counter substrate and surrounding the plurality of pixel electrodes. The agent layer is an empty cell that forms an injection port that communicates an internal space surrounded by the array substrate, the counter substrate, and the adhesive layer with an external space;
A liquid crystal material having a negative dielectric anisotropy filling the internal space;
Comprising a sealing body closing the injection port,
Each of the plurality of pixel electrodes is provided with a plurality of slit patterns,
Each of the plurality of slit patterns includes a slit extending in a third direction intersecting the first and second directions and a slit extending in a fourth direction intersecting the first to third directions. It has a structure arranged in the direction,
Each of the plurality of slit patterns has the same shape and orientation as the pattern obtained by rotating the slit pattern adjacent to the second direction by 180 ° around an axis orthogonal to the first and second directions. ,
A plurality of convex patterns are respectively provided at positions corresponding to the plurality of pixel electrodes on the surface of the counter substrate facing the array substrate.
Each of the plurality of convex patterns has a structure in which hook-shaped protrusions extending in the third direction and hook-shaped protrusions extending in the fourth direction are arranged in the second direction,
Each of the plurality of convex patterns has the same shape and orientation as a pattern obtained by rotating the convex pattern adjacent thereto in the second direction by 180 ° around the axis.

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