JP2001100219A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device which is manufactured at a lower manufacturing cost by the production process simpler than heretofore. SOLUTION: This liquid crystal display device has a first substrate, a second substrate and a liquid crystal layer held between the first substrate and the second substrate. The first substrate has plural wall-like structures on the surface on a liquid crystal side. The plural wall-like structures have the plural first wall-like structures extending in a first direction an the plural second wall-like structures extending in a second direction intersecting with the first direction. The plural second wall-like structures are formed on the plural first walllike structures in intersection regions intersecting with the plural first wall- like structures and the thickness of the liquid crystal layer is regulated in the intersection regions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a liquid crystal display device. In particular, it relates to a liquid crystal display device having a wide viewing angle characteristic.

[0002]

2. Description of the Related Art Conventionally, as a display device using an electro-optic effect, a TN (twisted nematic) or STN (super twisted nematic) type liquid crystal display device using a nematic liquid crystal has been used.

As a technique for widening the viewing angle of these liquid crystal display devices, for example, Japanese Patent Application Laid-Open Nos. Hei 6-301015 and Hei 7-120728 disclose an axially symmetric liquid crystal region divided by polymer walls. A liquid crystal display device having aligned liquid crystal molecules, so-called ASM (Axially)
Symmetrically aligned Mi
A liquid crystal display device of a (crocell) mode is disclosed. A liquid crystal region substantially surrounded by polymer walls is typically formed for each pixel. Since the liquid crystal molecules of the ASM mode have liquid crystal molecules that are axially symmetrically aligned, the change in contrast is small even when the observer views the liquid crystal display from any direction, that is, has a wide viewing angle characteristic.

[0004] The ASM mode liquid crystal display device disclosed in the above publication is manufactured by subjecting a mixture of a polymerizable material and a liquid crystal material to polymerization induced phase separation.

A method of manufacturing a conventional ASM mode liquid crystal display device will be described with reference to FIG.

First, as shown in FIG. 7A, a substrate having a color filter and electrodes formed on one surface of a glass substrate 908 is prepared (step (a)).

Next, as shown in FIG. 7B, a polymer wall 91 for axially symmetrically aligning liquid crystal molecules is formed on the surface of the glass substrate 908 on which the electrodes and the color filters are formed.
7 are formed, for example, in a lattice shape (step (b)). Specifically, after a photosensitive resin material is spin-coated on a glass substrate 908 on which a color filter and an electrode are formed, the photosensitive resin material is exposed through a photomask having a predetermined pattern, and developed, whereby a grid-like high-profile is formed. Form a molecular wall. Here, the photosensitive resin material may be either a negative type or a positive type. As another method, a step of separately forming a resist film is increased, but the resist film may be formed using a non-photosensitive resin material.

Next, as shown in FIG. 7C, by exposing and developing a photosensitive resin material, columnar projections 920 are discretely formed on the top of a part of the polymer wall 917 by patterning (FIG. 7C). Step (c)).

Next, as shown in FIG. 7D, the surface of the glass substrate on which the polymer walls 917 and the columnar projections 920 are formed is covered with a vertical alignment agent 921 such as polyimide (step (d)).

On the other hand, an electrode (not shown) shown in FIG.
FIG. 7F shows the surface of the opposing glass substrate 902 on which
As shown in (1), the substrate is covered with a vertical alignment film 921 (step (e) and step (f)).

Next, as shown in FIG. 7 (g), the two substrates are bonded together with the surface on which the electrodes are formed facing inward to form a liquid crystal cell (step (g)). Here, the distance between the two substrates is determined by the sum of the heights of the polymer wall 917 and the columnar projections 920, so that a desired liquid crystal layer thickness (cell gap) can be obtained.

Next, as shown in FIG. 7 (h), a liquid crystal material is injected into the gap between the liquid crystal cells by a vacuum injection method or the like (step (h)).

Finally, as shown in FIG. 7 (i), for example, by applying a voltage between a pair of electrodes disposed opposite to each other, the alignment of the liquid crystal molecules in the liquid crystal region 915 is controlled to be axially symmetric. (Step (i)), the liquid crystal molecules in the liquid crystal region divided by the polymer wall 917 are oriented axially symmetrically about an axis 918 indicated by a broken line perpendicular to both substrates.

FIG. 8 shows a sectional structure of a conventional color filter. This color filter includes a black matrix (BM) for shielding a gap between colored patterns on a glass substrate, and red, green, and blue (R, G, and G) corresponding to each picture element.
The colored resin layer of B) is formed. On these, an overcoat (OC) layer made of an acrylic resin or an epoxy resin and having a thickness of about 0.5 to 2.0 μm is formed to improve smoothness and the like. A transparent electrode made of an object (ITO) film is formed.
Here, the black matrix film generally has a thickness of about 1
The colored resin layer is made of a metal chromium film having a thickness of 00 to 150 nm, and a resin material colored with a dye or a pigment is used, and its film thickness is generally about 1 to 3 μm.

As a method of forming the color filter,
A method of patterning a photosensitive colored resin layer formed on a substrate by using a photolithography technique is used.
For example, by using a photosensitive resin material of each color of red (R), green (G), and blue (B), forming, exposing, and developing each photosensitive colored resin, respectively, the R, G, B A color filter can be formed. The method of forming the photosensitive colored resin layer includes a method of applying a liquid photosensitive colored resin material diluted with a solvent to a substrate by spin coating or the like, and a method of transferring a photosensitive colored resin material formed into a dry film. and so on. By manufacturing the above-described ASM mode liquid crystal display device using the color filters thus formed, a color liquid crystal display device having a wide viewing angle characteristic can be obtained.

[0016]

However, the present inventor has found that the conventional ASM mode liquid crystal display device has the following problems.

In the above-described conventional ASM mode liquid crystal display device, a polymer wall for orienting liquid crystal molecules in an axially symmetric manner and a thickness of a liquid crystal layer (cell gap) are different from those of a normal liquid crystal display device. Therefore, it is necessary to newly provide a columnar projection for defining the above. Since the number of new steps for forming the polymer wall and the columnar protrusion increases, the yield decreases and the manufacturing cost increases.

On the other hand, if the cell gap is defined by using spacer beads which are generally used conventionally instead of defining the cell gap by using columnar projections, the display quality easily fluctuates depending on the distribution density of the spacer beads. .
Specifically, when a large number of spacer beads are scattered and a large number of spacer beads are present in the liquid crystal region substantially surrounded by the polymer wall, the axially symmetric alignment of the liquid crystal molecules is disturbed, and the viewing angle characteristics of the liquid crystal display device are reduced. descend. Conversely, when the scattering density of the spacer beads is reduced, the strength required to maintain the cell gap cannot be obtained, and the predetermined cell gap cannot be maintained, resulting in a marked decrease in display quality. Also, if there is a variation in the scattering density of the spacer beads in the liquid crystal cell (in the display area), a variation occurs in the cell gap, and the brightness and the display color become uneven. Therefore, in order to prevent such a problem from occurring and to manufacture a stable liquid crystal display device, it is necessary to precisely control the density of the spacer beads to be dispersed, which causes an increase in manufacturing cost.

Since the above-mentioned columnar projections are formed by using a photolithography process, it is possible to avoid the problem relating to the distribution density when using spacer beads. However, since the columnar projections are finer than the polymer wall and need to be formed on the polymer wall, the step of forming the columnar projections requires high alignment accuracy, which increases the manufacturing cost and This is likely to be a factor in lowering the yield.

Also, in a liquid crystal display device in a display mode other than the ASM mode, a predetermined position (outside the picture element area)
It is desired to develop a technique for forming spacers at a predetermined density. The present invention has been made to solve the above-described problems, and has as its object to provide a liquid crystal display device manufactured at a lower manufacturing cost by a simpler manufacturing process than before.

[0021]

A liquid crystal display device according to the present invention comprises a first substrate, a second substrate, the first substrate and the second substrate.
A liquid crystal layer sandwiched between the substrate and the substrate, wherein the first substrate has a plurality of wall-shaped structures on a surface on the liquid crystal side,
The plurality of wall-shaped structures include a plurality of first structures extending in a first direction.
It has a wall-like structure and a plurality of second wall-like structures extending in a second direction intersecting the first direction, wherein the plurality of second wall-like structures are the plurality of first wall-like structures. The liquid crystal layer is formed on the plurality of first wall-shaped structures in an intersecting region that intersects with the first wall-like structure, and the thickness of the liquid crystal layer is defined in the intersecting region.

The liquid crystal layer is divided into a plurality of liquid crystal regions by the plurality of first wall structures and the plurality of second wall structures. It is preferable that the substrate is oriented symmetrically about an axis perpendicular to the surface of one substrate.

It is preferable that the plurality of first wall-like structures have a light shielding function.

It is preferable that the plurality of second wall-shaped structures have a light-transmitting function.

It is preferable that the plurality of first wall-like structures and the plurality of second wall-like structures have the same height.

Hereinafter, the operation of the present invention will be described.

The liquid crystal display device of the present invention has a plurality of wall-like structures on the liquid crystal layer side of one substrate. The wall-like structure includes a first wall-like structure extending in a first direction, and a second wall-like structure extending in a second direction different from the first direction.
The first and second wall-like structures intersect (typically, orthogonally) with each other to form an intersection area. The plurality of first wall-shaped structures and the plurality of second wall-shaped structures are formed in stripes parallel to each other. The first wall-like structure and the second
In the intersection region with the wall-like structure, the second wall-like structure is formed on the first wall-like structure, and the thickness (cell gap) of the liquid crystal layer of the liquid crystal display device is defined in the intersection region. Is done. Therefore, it is not necessary to form a structure other than the first wall-like structure and the second wall-like structure in order to define the cell gap of the liquid crystal display device. In other words, there is no need to form columnar projections provided for defining the cell gap in the related art. Since the first and second wall-shaped structures can be formed in substantially the same process as the conventional polymer wall, the high alignment accuracy required for forming the conventional columnar projection is not required. As a result, the liquid crystal display device of the present invention can be manufactured by a simpler process than before, and the manufacturing cost can be reduced.

Further, the first wall-like structure and the second wall-like structure divide the liquid crystal layer into a plurality of liquid crystal regions, and divide the liquid crystal molecules in the liquid crystal regions around an axis perpendicular to the surface of the first substrate. Can be made to have an axially symmetric orientation. That is, it can function as a polymer wall of the above-described conventional ASM mode liquid crystal display device. Accordingly, a liquid crystal display device having a wide viewing angle characteristic, which is manufactured at a lower manufacturing cost than before, is provided. Typically, the cross-sectional shape of each of the first and second wall-shaped structures in a direction perpendicular to the direction of extension is trapezoidal, and the first and second wall-shaped structures have a top surface and a tapered side surface. On the other hand, for example, the liquid crystal molecules are controlled to be vertically aligned using a vertical alignment film.

As described above, by making the first and second wall-like structures also function as conventional ASM mode polymer walls, the effect of the present invention is great. However, the present invention provides a liquid crystal of another display mode. It can be applied to a display device. The first mentioned above
By using the structure having the second wall-shaped structure, the spacer can be formed outside the picture element region with a sufficient density by a relatively simple process. Therefore, the display quality can be improved and the manufacturing cost can be reduced.

By employing the first wall-like structure having a light-shielding function, the first wall-like structure can also serve as a black matrix. Therefore, it is not necessary to separately form a black matrix. Further, in the conventional ASM mode liquid crystal display device, in the step of forming the black matrix, the first wall-like structure that can function as a part of the wall-like structure for forming the liquid crystal molecules to be axially symmetrically formed is formed. be able to. Therefore, the manufacturing process can be further simplified (the number of manufacturing steps can be reduced), and the manufacturing cost of the liquid crystal display device can be further reduced. For example,
The first wall-shaped structure formed using the black resin functions as a black matrix, blocks transmitted light from the periphery of the plurality of liquid crystal regions, prevents unnecessary interference, and improves display quality. When configuring a color liquid crystal display device, stripe-shaped R, G, and B colored layers are formed in parallel with the stripe-shaped first wall-shaped structure, and each colored layer has an end in the width direction. Preferably, it is formed so as to be located on the top surface of the first wall-shaped structure. By forming in this way,
The alignment accuracy required in the step of forming the colored layer can be reduced. In other words, the yield of the colored layer forming step can be improved.

By employing the second wall-like structure having a light-transmitting function, the liquid crystal layer located on the second wall-like structure contributes to display. That is, the aperture ratio of the liquid crystal display device can be improved.

By making the heights of the first wall-like structure and the second wall-like structure equal, the influence of the wall-like structure on liquid crystal molecules in a region substantially surrounded by the wall-like structure is uniform. become. For example, in an ASM mode liquid crystal display device, since each of the liquid crystal regions is substantially surrounded by a wall-shaped structure having the same height, the axially symmetric alignment of the liquid crystal molecules in each liquid crystal region is stabilized. Therefore, a liquid crystal display device capable of high-quality display can be provided.

[0033]

Embodiments of the present invention will be described below with reference to the drawings. The embodiment of the present invention will be described with an example of an ASM mode liquid crystal display device, but as described above, the present invention can be applied to a liquid crystal display device of a display mode other than the ASM mode.

FIG. 1 schematically shows a sectional structure of an ASM mode liquid crystal display device 100 according to an embodiment of the present invention.
FIG. 2 is a schematic perspective view of the liquid crystal display device 100 on the first substrate 101 side. FIG. 3 is a top view (viewed from a direction perpendicular to the substrate) of the first substrate 101 of the liquid crystal display device 100 according to the embodiment of the present invention, and FIG.
This corresponds to a cross-sectional view along line -X '. In the present embodiment, a configuration using a liquid crystal material having negative dielectric anisotropy and a vertical alignment film is illustrated, but the present embodiment is not limited thereto.

As shown in FIG. 1, the liquid crystal display device 100 includes a first substrate 101, a second substrate 102, and a liquid crystal comprising liquid crystal molecules (not shown) having a negative dielectric anisotropy sandwiched between the first and second substrates. And a layer 150.

The first substrate 101 is configured as follows. On a first transparent substrate 111 such as a glass substrate, a plurality of stripe-shaped first wall-like structures 121 each extending in a direction perpendicular to the paper surface are formed. Here, an example in which the first wall-like structure 121 has a light blocking function and also functions as a black matrix will be described; however, a black matrix may be separately formed. On the first substrate 101, stripe-shaped red, green, and black stripes extending in parallel with the stripe-shaped first wall-shaped structure (black matrix) 121.
Blue colored resin layers 131, 132, and 133 are formed. The ends of the colored layers 131, 132 and 133 in the width direction are the first wall-shaped structures 1 having a trapezoidal cross-sectional shape.
21 is formed on the top surface. The first transparent electrode 1 is formed on the colored layers 131, 132 and 133.
41 are formed. Further, the plurality of first wall-like structures 12
A plurality of stripe-shaped second wall-shaped structures 122 are formed so as to cross 1 (see FIG. 2). The second wall-like structure 122 is provided at the intersection region 125 with the first wall-like structure 12.
1. Further, the liquid crystal layer 15 is formed on the surface of the first substrate 101 on which the liquid crystal layer 150 is formed.
A vertical alignment film (not shown) for aligning the liquid crystal molecules (not shown) of at least one of the first transparent electrode 141 and the second
It is provided so as to cover the wall-like structure 122.

The second substrate 102 is configured as follows. Liquid crystal layer 15 of second transparent substrate 112 such as a glass substrate
The second transparent electrode 142 is formed on the zero-side surface. Further, a vertical alignment film (not shown) is formed so as to cover the second transparent electrode 142.

As shown in FIGS. 1 and 2, in the liquid crystal display device 100, the thickness (cell gap) of the liquid crystal layer 150 is defined in the intersection region 125. In the illustrated example, the thickness of the liquid crystal layer 150 is the first wall-like structure 1.
21 and the sum of the heights of the second wall-like structures 122.
When the coloring layers 131, 132, and 133 are not located on the top surface of the first wall-shaped structure, the substantial thickness of the liquid crystal layer 150 is reduced by the thickness of the coloring layer. In the intersection area 125, the second substrate 102 and the second wall-like structure 12
2 and between the first wall-like structure 121 and the second wall-like structure, if necessary, other structures may be formed.

Thus, the first wall-like structure 121 and the second
By forming the wall-like structures 122 so as to intersect with each other and forming the second wall-like structures 122 on the first wall-like structures in the intersection area, the cell gap conventionally required is defined. Therefore, it is not necessary to form a columnar projection for performing the process. First wall-like structure 121 and second wall-like structure 1
22 can be formed in substantially the same process as the conventional polymer wall, and therefore does not require the high alignment accuracy required for forming the conventional columnar projection. When the first wall-like structure 121 is used as a black matrix, the manufacturing process can be further simplified. Therefore, the yield does not decrease due to the step of forming the structure for defining the cell gap, the manufacturing process is simplified, and the material cost and the manufacturing cost for maintaining the manufacturing apparatus are reduced.

Further, the first wall-like structure 121 and the second
The wall-like structure 122 includes a liquid crystal layer 150 formed of a plurality of liquid crystal regions 1.
The liquid crystal is divided into 51, and has an effect of axially symmetrically aligning the liquid crystal molecules 153 in the liquid crystal region 151. That is, as shown in FIG. 3, when viewed from a direction perpendicular to the substrate (display surface), the liquid crystal region 151 is defined by the first wall-shaped structure 121 and the second wall-shaped structure 122, and The structure 121 and the second wall-like structure 122 substantially surround the liquid crystal region 151, respectively. The first wall-like structure 121 and the second wall-like structure 122 are formed, for example, via a vertical alignment film formed so as to cover them, and the top surface of the first and second wall-like structures and the tapered shape. The alignment of the liquid crystal molecules is regulated so that the liquid crystal molecules are aligned perpendicular to the side surface. as a result,
The liquid crystal molecules in the liquid crystal region substantially surrounded by the first wall-like structure 121 and the second wall-like structure 122 are oriented axially symmetric about an axis perpendicular to the substrate.

Further, when each of the liquid crystal regions 151 is structured so as to be substantially surrounded by the wall structures having the same height, the liquid crystal molecules in the liquid crystal regions have an alignment regulating force from the wall structures. Since the influence is uniform, the axially symmetric alignment of the liquid crystal molecules in each liquid crystal region is stabilized. As a result, high-quality display can be performed. Therefore, it is preferable that the first wall-shaped structure and the second wall-shaped structure have the same height.

Further, from the viewpoint of the injection speed of the liquid crystal material, the plurality of second wall-shaped structures are formed in a stripe shape extending in a direction perpendicular to the first wall-shaped structures (each second wall-shaped structure is a strip shape). ) Is preferable. For example, as shown in FIG. 4 (comparative example), a structure 127 in which the top surface of the first wall-shaped structure 121 is entirely covered with the second wall-shaped structure 122.
In this case, the liquid crystal material can move only in a direction parallel to the direction in which the first wall-shaped structure 121 extends when the liquid crystal is injected, and the resistance for injecting the liquid crystal material is large. Therefore, the time required for injecting the liquid crystal material becomes very long, and the manufacturing throughput of the liquid crystal display device is reduced. Therefore, it is preferable to form the strip-shaped second wall-shaped structure in a stripe shape so as to be orthogonal to the first wall-shaped structure.

The widthwise ends of the colored layers 131, 132 and 133 are formed so as to be located on the top surface of the first wall-like structure 121 having a trapezoidal cross section. Further, on the first wall-like structure 121, the colored resin layer 13
A gap 134 is formed between each of 1, 132 and 133. By forming in this manner, the positioning accuracy required in the step of forming the colored layer can be reduced. Since the gap 134 is formed on the first wall-like structure 121 functioning as a black matrix, the display quality does not deteriorate. In addition,
The position of the gap 134 is preferably on the top surface of the first wall-shaped structure in order to stabilize the axially symmetric alignment of the liquid crystal molecules in the liquid crystal region 151 and enhance the viewing angle characteristics. When the gap 134 is not on the top surface of the first wall-like structure, the liquid crystal molecules
A difference occurs in the alignment regulating force received from the wall-shaped structure and the second wall-shaped structure.

By forming the second wall-like structure 122 using a material having a light transmitting function, the second wall-like structure 1 is formed.
22 can contribute to the display,
The aperture ratio of the liquid crystal display device can be increased. Accordingly, a liquid crystal display device which can display bright images and is manufactured at low manufacturing cost can be provided, which is preferable.

As the configuration and the driving method of the first transparent electrode 141 and the second transparent electrode 142 for driving the liquid crystal layer 150, a known electrode configuration and a driving method can be used. For example, an active matrix type or a simple matrix type can be applied. Further, a plasma address type can be applied. In this case, a plasma discharge channel is provided instead of one of the first electrode 141 and the second electrode 142. Note that the first substrate and the second substrate may be switched depending on the electrode configuration and the driving method to be applied. That is, the second substrate may have the second wall-shaped structure 122.

The method for manufacturing the liquid crystal display device 100 of the present embodiment will be specifically described below.

First, the first substrate 101 is manufactured, for example, as follows. A photosensitive black resin (for example, V259 manufactured by Nippon Steel Chemical Co., Ltd.) is formed on a first transparent substrate 111 such as a glass substrate.
BKIS) is applied by a spin coating method. Using a mask having a predetermined stripe pattern, a black matrix (BM) 121 is patterned by photolithography. For example, the height of the fired black matrix 121 is 3.0 μm, the width is 40 μm, and the distance between adjacent black matrices is 162 μm.

After forming the black matrix 121,
Striped colored resin layers 131, 132, and 13
3 is formed in a conventional manner. For example, the thickness of each of the colored resin layers 131, 132, and 133 after firing is 1.2 μm.
m and the width are set to 190 μm. Thereby, the colored resin layers 131, 132, and 133 are formed so as to overlap the black matrix 121. The width of a portion where each of the colored resin layers 131, 132, and 133 overlaps the black matrix 121 is 14 μm on one side.

Thereafter, an ITO film, for example, is formed to a thickness of 150 nm on the entire surface of the obtained first transparent substrate 111 by a sputtering method, and is patterned to form a first transparent electrode 141. For example, the height of the second wall-like structure 122 is 3.0 μm.
m and the width are 30 μm. A vertical alignment film (not shown) is formed by spin-coating an alignment film material (for example, JALS-204, a polyimide resin manufactured by Nippon Synthetic Rubber Co., Ltd.) on the entire surface of the obtained substrate to obtain a first substrate 101. .

On the other hand, the second substrate 102 is manufactured, for example, as follows. Second transparent substrate 11 such as a glass substrate
2, an ITO film is formed and patterned to form a second transparent electrode 142 having a thickness of, for example, 150 nm. Further, a vertical alignment film (not shown) is formed thereon by spin-coating an alignment film material (for example, JALS-204, a polyimide resin manufactured by Japan Synthetic Rubber Co., Ltd.).

The first substrate 101 thus manufactured
And the second substrate 102 are joined. The cell gap is the first
It is defined in the intersection region 125 between the wall-like structure 121 and the second wall-like structure 122, and in the present embodiment, the intersection region 1
The height of 25 is the sum of the height of 3.0 μm of the first wall-like structure 121 and the height of 3.0 μm of the second wall-like structure, that is, 6.
0 μm. First substrate 101 and second substrate 1 joined together
02, an n-type liquid crystal material (Δε = −4.0, Δn
= 0.08, a cell gap of 6.0 µm and a chiral agent added so as to give a 90 degree twist), and the liquid crystal layer 1
Form 50. The injection of the liquid crystal material can be performed in a sufficiently short time.

In order to stabilize the central axis of the axially symmetric alignment of the liquid crystal molecules in the liquid crystal region of the liquid crystal layer 150, the liquid crystal layer 15
A voltage of 4.0 V is applied to 0. Immediately after the application of the voltage, a plurality of central axes are formed. However, when the voltage is continuously applied, one central axis is provided for each liquid crystal region 151, and one axially symmetric alignment region (monodomain) is formed. A polarizing plate is arranged on the first substrate and the second substrate on the side opposite to the liquid crystal layer 150 so as to be in a crossed Nicols state, and the liquid crystal display device 100 is completed.

The thus obtained liquid crystal display device 10
No. 0 has a wide viewing angle characteristic, does not vary the cell gap, and can perform high-quality display.

The liquid crystal display device 100 of the present embodiment is not limited to the above example. The height of each of the first wall-like structure 121 and the second wall-like structure 122 is preferably about 0.5 to
It is 4 μm, and more preferably about 2-3 μm. A cell gap of about 4 to 6 μm is most preferable from the viewpoint of the response speed, viewing angle characteristics, and injection speed of the current liquid crystal material. Typically, the height of the first wall-like structure 121 and the second wall-like structure 122 Since the sum defines the cell gap,
Most preferably, the height of each of the wall structures is about 2-3 μm. The width of the first wall-like structure 121 and the second wall-like structure 122 depends on the size of the display panel, but is preferably about 5 to 80 μm, respectively. Generally, it is preferable that the width of the wall-shaped structure is narrow, but from the viewpoint of processing accuracy, it is practically 5 μm or more. Further, in consideration of the fact that the side surface of the wall-shaped structure is formed in a tapered shape, the thickness is more preferably about 15 to 60 μm. When the first wall-like structure 121 functions as a black matrix, it is preferable to use the above-described black resin. However, a black matrix is separately formed using chromium or the like, and the first wall is formed using a transparent resin. The structure 121 may be formed. Examples of the material of the second wall-like structure 122 include an acrylic resin, an epoxy resin, and a polyimide resin. In particular, an acrylic resin is preferable from the viewpoints of translucency and ease of processing.

The operation of the liquid crystal display device 100 according to the present embodiment will be described with reference to FIGS. In a state where no voltage is applied to the liquid crystal region 151, FIG.
As shown in (a), the liquid crystal molecules 153 are
And 102, the liquid crystal layer is vertically aligned with the substrate surface by the alignment control force of the vertical alignment film (not shown) formed on the liquid crystal layer side.
When this state is observed with a crossed Nicol state polarizing microscope, a dark field is obtained as shown in FIG. 5B (normally black state). When a voltage for halftone display is applied to the liquid crystal region 151, the liquid crystal molecules 153 having negative dielectric anisotropy
Since a force acts to orient the long axis of the molecule perpendicular to the direction of the electric field, the molecule tilts from the direction perpendicular to the substrate surface as shown in FIG. 5C (halftone display state). At this time, a plurality of first
By the action of the wall-shaped structure and the plurality of second wall-shaped structures, the liquid crystal molecules 153 in the liquid crystal region 151 are axially symmetrically arranged around a central axis 155 indicated by a broken line in the drawing. When this state is observed with a polarizing microscope in a crossed Nicols state, FIG.
As shown in (d), an extinction pattern is observed in the direction along the polarization axis.

In the present specification, the term “axially symmetric orientation” includes concentric (tangential) and radial shapes. Furthermore, for example, the spiral orientation shown in FIG. 6 is also included. This spiral alignment can be obtained by adding a chiral agent to the liquid crystal material to give a twist alignment force. Liquid crystal area 15
1B in the upper part 151T and the lower part 151B of FIG.
As shown in (1), the liquid crystal layer is spirally oriented, concentrically oriented at 151M near the center, and twisted with respect to the thickness direction of the liquid crystal layer. The central axis of the axisymmetric orientation generally coincides substantially with the normal direction of the substrate.

When the liquid crystal molecules are axially symmetrically aligned,
The viewing angle characteristics can be improved. When the liquid crystal molecules are axially symmetrically aligned, the refractive index anisotropy of the liquid crystal molecules is averaged in all azimuthal directions, so that the viewing angle characteristic seen in the halftone display state of the conventional TN mode liquid crystal display device is azimuthal. There is no problem that the angle differs greatly depending on the angular direction. Also,
If a horizontal alignment film and a liquid crystal material having a positive dielectric anisotropy are used, an axially symmetric alignment can be obtained even when no voltage is applied. At least a wide viewing angle characteristic can be obtained if the structure is configured to be axially symmetrical with a voltage applied.

[0058]

The liquid crystal display device according to the present invention has a first wall-shaped structure and a second wall-shaped structure formed on the liquid crystal layer side of one of the substrates. , The second wall-shaped structure is formed on the first wall-shaped structure, and the thickness (cell gap) of the liquid crystal layer of the liquid crystal display device
Is defined in the intersection area. Therefore, it is not necessary to form a structure other than the first wall-shaped structure and the second wall-shaped structure in order to define the cell gap of the liquid crystal display device. The spacer can be formed by a simple and convenient process. Therefore, according to the present invention, a liquid crystal display device with high display quality can be manufactured by a simpler process than before, and the manufacturing cost of the liquid crystal display device can be reduced.

Further, by making the first wall-like structure function as a black matrix, the manufacturing process of the liquid crystal display device can be further simplified. Further, by making the first and second wall-like structures also function as conventional ASM mode polymer walls, an ASM mode liquid crystal display device can be manufactured by a simpler process than before.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a schematic perspective view of a first substrate side of the liquid crystal display device of the present embodiment.

FIG. 3 is a schematic top view on the first substrate side of the liquid crystal display device of the present embodiment.

FIG. 4 is a diagram schematically showing a wall-like structure of a comparative example for explaining the operation of the present invention.

FIG. 5 is a schematic diagram illustrating the operation of the ASM mode liquid crystal display device. (A) and (b), when no voltage is applied, (c)
And (d) show the time of voltage application.

FIG. 6 is a schematic diagram illustrating an axially symmetric alignment state of liquid crystal molecules in a liquid crystal region.

FIG. 7 is a diagram showing a method for manufacturing a conventional ASM mode liquid crystal display device.

FIG. 8 is a sectional view of a conventional color filter substrate.

[Explanation of symbols]

 Reference Signs List 100 liquid crystal display device 101 first substrate 102 second substrate 111 first transparent substrate 112 second transparent substrate 121 first wall-like structure (black matrix) 122 second wall-like structure 131, 132, 133 colored resin layer 141 1 transparent electrode 142 second transparent electrode 150 liquid crystal layer 151 liquid crystal region 153 liquid crystal molecule 155 symmetry axis (center axis)

Claims (5)

[Claims] 1. A liquid crystal device comprising: a first substrate; a second substrate; and a liquid crystal layer sandwiched between the first substrate and the second substrate. A plurality of wall-like structures, wherein the plurality of wall-like structures extend in a first direction.
It has a wall-like structure and a plurality of second wall-like structures extending in a second direction intersecting with the first direction, wherein the plurality of second wall-like structures are the plurality of first wall-like structures. A liquid crystal display device formed on the plurality of first wall-shaped structures in an intersecting region intersecting with the first wall-shaped structure, wherein the thickness of the liquid crystal layer is defined in the intersecting region. 2. The liquid crystal layer is divided into a plurality of liquid crystal regions by the plurality of first wall structures and the plurality of second wall structures, and liquid crystal molecules in the plurality of liquid crystal regions are: The liquid crystal display device according to claim 1, wherein the liquid crystal display device is oriented axially symmetric about an axis perpendicular to the surface of the first substrate. 3. The liquid crystal display device according to claim 1, wherein the plurality of first wall structures have a light blocking function. 4. The liquid crystal display device according to claim 1, wherein said plurality of second wall-shaped structures have a light transmitting function. 5. The liquid crystal display device according to claim 1, wherein the plurality of first wall-like structures and the plurality of second wall-like structures have the same height.