JPH0588177A - Liquid crystal display element - Google Patents

Abstract

PURPOSE:To decrease the contamination of substrates, the electrostatic breakdown of the respective elements, etc., formed on the substrates, the defects of liquid crystal images, etc., and to uniformize the orientation to liquid crystal molecules. CONSTITUTION:A pair of the substrate parts 1, 2 having substrates 11, 21 and oriented films 13, 23 coating these substrates are disposed apart a specified distance by disposing the oriented film 13, 23 side on the opposite surfaces. A liquid crystal 3 is sealed between these two substrate parts. Periodic or non- periodic rugged patterns which are respectively asymmetrical in the sectional shape of the ruggedness are formed by a chemical treatment on the surfaces of the substrates 11, 21 and/or the opposite surfaces of the oriented films 13, 23 respectively in the substrate parts 1, 2. The opposite surfaces of the respective substrate parts in contact with the liquid crystal have the periodic or non- periodic rugged patterns which are respectively asymmetrical in the sectional shape of the ruggedness along the rugged patterns on the surfaces of the substrates 11, 21 and/or the opposite surfaces of the oriented films 13, 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device.

[0002]

2. Description of the Related Art In general, a liquid crystal display device includes a pair of substrates arranged to face each other with a constant distance, an alignment film covering surfaces of the substrates facing each other, and an alignment film between the substrates. It is composed of a liquid crystal enclosed via an alignment film. In such a liquid crystal display element, a transparent electrode is laminated on the substrate in the pixel portion, and an alignment film is further formed on the transparent electrode, and a voltage is applied to the liquid crystal by the transparent electrode. In particular, in recent years, as a liquid crystal display element used in an active matrix type display system, a liquid crystal display element in which a driving element such as a thin film transistor (TFT, Thin Film Transistor) is mounted on one substrate in the pixel portion has been developed. It has been put to practical use.

Among the constituent members of the liquid crystal display device as described above, the alignment film is subjected to various alignment treatments on the surface of the insulating film for the purpose of aligning liquid crystal molecules in a certain direction on the surface in contact with the liquid crystal. It is a thing. As such an alignment treatment, a treatment called a rubbing method has hitherto been widely performed.

In this rubbing method, the surface of an insulating polymer film or the like formed on a substrate which is in contact with liquid crystal is
In this method, a fibrous substance such as cloth is rubbed in a certain direction (rubbing) to give the film surface an alignment ability with respect to liquid crystals. Regarding the orientation ability, the theory that the tilt angle of the liquid crystal molecules (the angle at which the liquid crystal molecules are inclined and oriented with respect to the substrate) is controlled by the minute irregularities formed on the surface of the polymer film by rubbing (shape effect theory) Further, there is a theory (interaction effect theory) that the polymer that is stretched when the surface of the film is rubbed to form an alignment of the polymer, and the orientation and uniformity of the alignment of liquid crystal molecules are controlled according to this alignment. Proposed. It is considered that the rubbing direction determines the final visual direction of the liquid crystal display image. The alignment treatment by this rubbing method can use a simple and very simple manufacturing apparatus, can form a large amount of alignment films in a short time, and has an alignment regulating force for the liquid crystal molecules of the processed alignment films. It is most frequently used in the manufacture of current liquid crystal display devices because it is extremely strong.

However, according to the rubbing method, a uniform rubbing treatment is possible in a liquid crystal display device having a small display area (small area of the alignment film), but on the other hand, a large display area (large area of the alignment film). In
It becomes difficult to uniformly set the contact pressure of the fibrous substance on the film surface on the substrate. This contact pressure is not easy to control, and also changes partially and over time due to the durability of the fibrous material used. From the above, the performance of the alignment film formed becomes non-uniform throughout the film, reproducibility is difficult to show even in mass production, and the alignment uniformity of the liquid crystal substance in the display image of the liquid crystal display element becomes insufficient. Become.

Further, in the rubbing method, the substrate and its peripheral portion are contaminated by the constituent components (filament waste, etc.) of the fibrous material used. Furthermore, a step of rubbing a dielectric material such as a polymer film with a cloth is included, and a large amount of static electricity is generated on the alignment film. For this reason, the substrate surface is charged, dust is adsorbed, and the gap between the substrates expands beyond a predetermined interval,
A defect occurs in the formed liquid crystal display element. Further, in the step of rubbing the surface of the thin film on the substrate with a cloth, unnecessary scratches are generated on the substrate surface, which also causes a defect in the liquid crystal display image.

The drawbacks of the alignment treatment by the rubbing method as described above become more serious problems especially in the liquid crystal display element used in the active matrix type display system. In such a liquid crystal display element, the drive element provided on the substrate is destroyed by static electricity generated during rubbing, which further increases the defect rate of the liquid crystal display element. Further, in the liquid crystal display element, the surface of the thin film (orientation film) covering the surface of the substrate on which the driving element in the pixel portion is mounted has unevenness due to the presence of the active element, and flattening is impaired. In addition, it is impossible to rub the entire surface of the thin film uniformly.
As a result, uneven treatment occurs during rubbing, and the distribution of the alignment ability of the formed alignment film with respect to the liquid crystal becomes uneven,
Image loss occurs on the liquid crystal display. Further, the rubbing process direction is likely to be restricted, which restricts the visual direction of the liquid crystal display image, narrows the application range of the formed liquid crystal display element, and lowers its practical value.

As described above, the current rubbing method has many problems in the quality of the liquid crystal display device. Therefore, there is a strong demand for an alignment treatment method (alignment film forming method) that replaces the rubbing method, and several studies have been reported to meet this demand.

The alignment film forming method currently being studied is based on the following facts. That is, when liquid crystal molecules are placed on a substrate (alignment film) having linear concave and convex grooves arranged at equal intervals, the liquid crystal molecules are aligned in the direction along the grooves. Regarding this fact, Physical Review A24 (5) 2713 (1981) by HV Kennel et al., A. Sugiyama
Jpn.J.Appl.Phys.20 (7) 1343 (1981) and the like. For example, Japanese Patent Application Laid-Open No. 60-60624 by Kazuo Yokoyama et al. Discloses a method of forming grating-shaped irregularities by irradiating the surface of a substrate with two-beam interference fringes of laser light. Further, Japanese Patent Application Laid-Open No. 61-11725 by Tanaka et al. Discloses a method of forming an alignment film by transferring and exposing a mask pattern on a negative photosensitive PVA film. However, these methods have not reached the industrial level of implementation. For example, the above-mentioned JP-A-61-117
The No. 25 alignment film does not have sufficient heat resistance for use in a liquid crystal display device.

Further, in the liquid crystal display device having the above-mentioned alignment film, the alignment uniformity of the liquid crystal molecules cannot be sufficiently achieved. It is presumed that this is because the cross-sectional shape of each unevenness of the alignment film is a symmetrical shape such as a rectangle. That is, it is considered that it is difficult to arbitrarily control the orientation angle of the liquid crystal molecules with respect to the groove direction forming the irregularities when the sectional shapes of the irregularities are symmetrical.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its object is to reduce contamination of the substrate, electrostatic breakdown of each element formed on the substrate, and the like. Accordingly, it is an object of the present invention to provide a high-performance liquid crystal display device which has very few defects in a liquid crystal image and can achieve alignment uniformity with respect to liquid crystal molecules.

[0012]

A liquid crystal display device of the present invention has a substrate and an alignment film formed of a polymer material that covers the surface of the substrate, and the alignment film side is a facing surface with a constant distance. A pair of substrate portions arranged apart from each other and a liquid crystal enclosed between the pair of substrate portions are provided, and in each of the substrate portions, the substrate surface and / or the facing surface of the alignment film is chemically treated. A periodic or non-periodic concave-convex pattern in which the cross-sectional shape of each concave-convex is asymmetric is formed, and the facing surface in contact with the liquid crystal of each substrate portion,
It is characterized in that it has a periodic or aperiodic uneven pattern in which the cross-sectional shape of each uneven is asymmetrical along the uneven pattern of the substrate surface and / or the facing surface of the alignment film. Hereinafter, details of the present invention will be described.

In the liquid crystal display device of the present invention, the shape of the facing surface in contact with the liquid crystal of the substrate portion is a concavo-convex shape in which the cross-sectional shape of each concavo-convex is asymmetrical, and this concavo-convex shape controls the alignment of liquid crystal molecules. It is estimated that In general, the surface of the substrate portion facing the liquid crystal corresponds to the surface of the alignment film in contact with the liquid crystal. Therefore, the uneven shape of the surface of the alignment film in contact with the liquid crystal directly controls the alignment of the liquid crystal molecules. Become.

In the present invention, the fact that the cross-sectional shape of each concavo-convex pattern on the opposing surface of the substrate is asymmetric means that it is along the direction perpendicular to the direction of the valley line (recess) or ridge line (convex part) of the concavo-convex pattern. It means that the unevenness is an asymmetrical figure in the cross section.

In the liquid crystal display element of the present invention, the concavo-convex pattern on the facing surface of each substrate portion may be based on the shape of at least one of the substrate or the alignment film forming the substrate portion. That is, at least one surface of the substrate and the alignment film has a periodic or aperiodic uneven pattern in which the cross-sectional shape of each unevenness formed by chemical treatment is asymmetric, and such an uneven pattern is formed. It suffices that it finally appears on the opposite surface of the substrate portion that comes into contact with the liquid crystal.

The substrate constituting the substrate portion is usually made of a material such as glass, and may further have a thin film layer of copper or the like on the surface. By excavating this surface by a chemical treatment such as ion beam etching, a periodic or aperiodic uneven pattern in which the cross-sectional shape of each uneven is asymmetric can be provided.

On the other hand, the alignment film forming the substrate portion is
A thin film formed of a photosensitive polymer such as photosensitive (photocurable) polyimide is used. By subjecting this surface to a chemical treatment such as photolithography, the cross-sectional shape of each unevenness is asymmetrical or periodic. An aperiodic uneven pattern can be applied. When the surface of the substrate is treated to have an uneven pattern as described above, photo-curable polyimide, thermosetting polyimide, epoxy resin or the like can be used as the alignment film that covers the substrate. These resins are formed on a substrate having an uneven pattern and further cured to transfer the uneven pattern on the substrate.

As described above, in the liquid crystal display device of the present invention,
In both the substrate and the alignment film, a periodic or aperiodic uneven pattern in which the cross-sectional shape of each uneven is asymmetric is formed without using a conventional rubbing method.

Next, a specific example of the cross-sectional structure in the pixel portion of the liquid crystal display element of the present invention as described above will be described with reference to FIGS. 1 and 2. In the liquid crystal display element shown in FIG. 1, the alignment film surface in the substrate portion has a periodic or aperiodic uneven pattern in which the cross-sectional shape of each uneven portion is asymmetric, and this uneven pattern is the liquid crystal in the substrate portion. It appears on the surface in contact with.

In FIG. 1, 1 and 2 are substrate parts. The substrate unit 1 includes a substrate 11 and ITO (Indium Tin Oxid).
e) A laminate of a transparent conductive film 12 (transparent electrode) such as a film and an alignment film 13. The substrate portion 2 has a similar structure and is a laminated body of the substrate 21, the transparent conductive film 22 and the alignment film 23.
The substrate parts 1 and 2 are opposed to each other with a constant space such that the respective alignment films 13 and 23 are opposed to each other,
The liquid crystal 3 is enclosed in the facing surface.

In the substrate parts 1 and 2, the alignment film 13,
On each surface of 23, a periodic uneven pattern in which the cross-sectional shape of each unevenness is asymmetric is formed as shown in the figure,
This concavo-convex pattern appears on the surface of the substrate portion that is in contact with the liquid crystal. The uneven pattern may be aperiodic.

FIG. 2 is a perspective view showing the structure of the alignment film 23 in FIG. 1 in detail. As shown in FIG.
The cross-sectional shape of each unevenness 3 is an asymmetrical triangular figure, and these unevennesses are linearly arranged. In the liquid crystal display element of the present invention, since the unevenness of the cross-sectional shape formed on the surface of the alignment film or the surface of the substrate (unevenness of the surface of the substrate portion) regulates the orientation direction of the liquid crystal molecules, It is preferably a polygon having a plurality of corners. However, the corners of the protrusions are 1 to 2 points in consideration of the actual processing technique, and further, the corners existing at the same position in each of the protrusions and recesses are in principle linear. In particular, like the alignment film 23 shown in FIG.
That is, it is preferable that the cross-sectional shape of the irregularities is an asymmetric triangle, and it is particularly preferable that the following expressions (1) to (4) are satisfied in the shape. a <b (1) a + b = d (2) d <1.67 × 10 ⁻⁶ (3) h / d> tan 13 ° (4) (In the formula, a and b are inclined surfaces of each unevenness. Horizontal distance, d is one cycle of the unevenness, and h is the height of the unevenness (see FIG. 2).

In a liquid crystal display device in which the cross-sectional shape of the concavities and convexities on the opposing surface of the substrate is an asymmetric triangular shape, if the above formulas (1) to (4) are not satisfied, the alignment uniformity of the liquid crystal molecules, that is, the alignment. Degradation of order may occur. However, in the present invention, by considering the interaction between the alignment film and the liquid crystal material, it is sufficient to improve the alignment order of the liquid crystal molecules even in the liquid crystal display device that does not satisfy the above formulas (1) to (4). Is possible.

The liquid crystal display device of the present invention is applicable regardless of the type and molecular weight of liquid crystal molecules to be enclosed, and is applicable to general liquid crystal display systems, that is, simple matrix system and active matrix system. It is possible to

[0025]

In the liquid crystal display device of the present invention, the alignment state of the liquid crystal molecules is controlled by the concavo-convex pattern on the facing surface of the substrate portion. The concavo-convex pattern is formed by chemically treating the substrate that constitutes the substrate portion or the alignment film that covers the substrate. That is, in the liquid crystal display device of the present invention, the ability to align liquid crystal molecules is imparted without using the conventional rubbing method, and problems such as contamination of the substrate and electrical breakdown of the device are avoided, and the substrate Alignment treatment can be performed uniformly over the entire liquid crystal display image of a part.

Further, in the liquid crystal display element of the present invention, in the concavo-convex pattern on the opposing surface of the substrate portion, the cross-sectional shape of each concavo-convex pattern is asymmetric, and in particular, the vicinity of the opposing surface of the substrate portion in contact with the liquid crystal. Thus, it becomes possible to favorably control the orientation direction of the liquid crystal molecules. Further, by controlling this uneven shape, for example, one cycle of unevenness (d = a + b) in the alignment film shown in FIG. 2, height (h) of the convex portion, asymmetry (a: b) inclination angle (θ ) And the like, the orientation direction of the liquid crystal molecules, that is, the angle of the liquid crystal molecule major axis direction with respect to the valley line (recess) or the ridge line (projection) in the concave and convex grooves on the substrate surface, and the tilt angle, that is, It is possible to freely control the tilt angle of the liquid crystal molecules with respect to the surface of the substrate. In this way, alignment uniformity of liquid crystal molecules in the liquid crystal display device can be achieved.

[0027]

EXAMPLES Examples of the present invention will be described below. It should be noted that these examples are described for the purpose of facilitating the understanding of the present invention, and do not limit the present invention. Examples 1-5

A photosensitive polyimide film having a thickness of 700 to 2000 A (angstrom) was formed on each surface of the transparent substrate to form an alignment film layer. Then, the alignment film layer surface through an exposure mask having a periodic pattern of slits,
Exposure was performed using a parallel exposure machine (PLA-105, manufactured by Nikon Corporation). At this time, the line and space intervals in the exposure mask were set within the range of 1.67 to 0.9 μm. Subsequently, development and rinsing treatment were performed to remove unnecessary polyimide, and annealing was further performed at a temperature of 230 ° C. to form a periodic uneven pattern of rectangular cross section on the substrate.
The period of the concavo-convex portion in this pattern is determined by the distance between the lines and spaces of the exposure mask.

Next, in a large vacuum chamber, an ion beam etching process is performed on the alignment film layer having the concavo-convex pattern having a rectangular cross section so that the corners of the rectangular concavo-convex are cut off and the cross-sectional shape of each concavo-convex is asymmetric. To form a concavo-convex pattern. That is, an alignment film having an uneven pattern having a triangular cross section as shown in FIG. 2 was formed on a transparent substrate.

Using a pair of substrate parts having the concavo-convex pattern obtained as described above, liquid crystal was filled in according to a conventional method, and five types of liquid crystal display elements having different periods of the concavo-convex pattern on the surface of the substrate part (Example 1) ~ 5) were produced.

In each of the liquid crystal display elements of Examples 1 to 5, the alignment direction, tilt angle, and alignment order of the liquid crystal molecules were measured, and the relationship between these and the cycle of the concave-convex pattern on the substrate surface of the liquid crystal display element was measured. (Period dependence) was evaluated. The results are shown in Table 1 below. The inclination angle of each example in Table 1 corresponds to the angle θ in the unevenness of the shape shown in FIG.

The relationship between the alignment direction of liquid crystal molecules and the period of the concavo-convex pattern is shown in the diagram of FIG. In the figure, the vertical axis represents the alignment direction of the liquid crystal molecules, that is, the angle in the long axis direction of the liquid crystal molecules with respect to the valley line (recess) or ridge line (projection) in the uneven groove on the surface of the substrate, and the horizontal axis represents the uneven pattern. The respective cycles are shown. Examples 6-9

According to the same method as in Examples 1 to 5 except for the condition of the ion beam etching treatment, a transparent substrate was provided with a concavo-convex pattern in which the cross-sectional shape of each concavo-convex was an asymmetric triangle, as shown in FIG. An alignment film was formed, and a liquid crystal display device was produced by using the alignment film. Specifically, the angle between the ion beam irradiation direction and the substrate normal line during the ion beam etching process is a finite angle exceeding 0 ° ~ 76.4
Four types of liquid crystal display devices (Examples 6 to 9) having different inclination angles of unevenness on the surface of the substrate portion in contact with the liquid crystal were manufactured by changing the angle within the range of °.

In each of the liquid crystal display elements of Examples 6 to 9, the alignment direction, tilt angle, and alignment order of the liquid crystal molecules were measured, and the tilt angle of the concavo-convex pattern on the substrate surface of the liquid crystal display element was measured. The relationship (inclination angle dependence) was evaluated. The results are also shown in Table 1 below. Examples 10-14

A photoresist thin film having a thickness of 1 μm was formed on a glass substrate or a substrate corresponding thereto. next,
The photoresist thin film was exposed through a slit mask or using a laser holographic technique. Here, as the slit-shaped mask, Example 1 was used.
A mask similar to the exposure mask used in ~ 5 was used. Further, the laser holographic technology is to perform exposure on a photoresist thin film by using an interference pattern obtained by projecting a phase-controlled laser light (manufacturing technology for Echelette diffraction grating, Japanese patent). No. 1046763), an alignment film which requires a finer pattern, or a material which is difficult to be exposed by the exposure mask. Then, the photoresist thin film after exposure was developed and rinsed to form a resist thin film layer having a periodic slit pattern on the substrate. The period of the uneven portion in this pattern is
Spacing of the slit-shaped mask lines and spaces,
Alternatively, it is determined by the interference pattern in the laser holographic technology.

Next, in a large vacuum chamber, an ion beam etching process is performed using the resist thin film layer having the slit pattern as an etching resistant mask, and a glass substrate or a substrate corresponding thereto is excavated to form a cross-sectional shape of each unevenness. An uneven pattern having asymmetric triangles was formed.

Next, a thermosetting epoxy resin having a thickness of 2000 to 7000 is formed on the surface of the substrate having the uneven pattern as described above.
A film is formed by A, heated and baked to be hardened, and a similar uneven pattern, that is, an uneven pattern having a triangular cross section as shown in FIG. Then, an alignment film was formed.

Using a pair of substrate parts having the concavo-convex pattern obtained as described above, liquid crystal was sealed in a conventional manner, and five types of liquid crystal display elements having different periods of the concavo-convex pattern on the surface of the substrate part (Example 10). ~ 14) were produced.

In each of the liquid crystal display elements of Examples 10 to 14, the alignment direction of liquid crystal molecules, tilt angle,
And the orientation order was measured, and the relation (period dependence) between these and the period of the concavo-convex pattern on the substrate surface of the liquid crystal display device was evaluated. The results are shown in Table 1 below. Examples 15-18

In the same manner as in Examples 10 to 14 except for the condition of the ion beam etching treatment, a concavo-convex pattern having a triangular shape in which the cross-sectional shape of each concavo-convex is asymmetric was formed on the transparent substrate. A liquid crystal display element whose shape appeared on the surface of the substrate was prepared. For details, see Ion Beam
During the etching process, the angle between the ion beam irradiation direction and the substrate normal is changed within the range of a finite angle exceeding 0 ° to 76.4 °, and the inclination angle of the unevenness is different on the surface of the substrate that contacts the liquid crystal. Four types of liquid crystal display elements (Example 15 to
18) was produced.

In each of the liquid crystal display devices of Examples 15 to 18, the alignment direction of liquid crystal molecules, tilt angle,
The alignment order was measured, and the relationship between these and the inclination angle of the concavo-convex pattern on the substrate surface of the liquid crystal display element (inclination angle dependence) was evaluated. The results are also shown in Table 1 below.

[0042]

[Table 1]

From the results shown in Table 1, in the liquid crystal display device of the present invention, it is possible to freely control the alignment direction of the liquid crystal molecules, the tilt angle, etc. by changing the period of the concavo-convex pattern and the tilt angle. is there. In any case, the alignment order of the liquid crystal molecules is good, and the alignment uniformity of the liquid crystal molecules is sufficiently achieved. In addition, the light transmission characteristics of the liquid crystal display device of the present invention were evaluated as follows.

First, in accordance with the same method as in Examples 1 to 5, a substrate portion having a concavo-convex pattern in which the cross-sectional shape of each concavo-convex was asymmetric and the period of concavo-convex was 0.8 μm was formed. The pair of substrate parts are arranged so that
A liquid crystal cell corresponding to the liquid crystal display element of the present invention was formed by facing each other at 90 ° and enclosing a liquid crystal between the substrate sails. The liquid crystal cell was sandwiched between parallel Nicols, and the light transmittance (light source 570 nm) when rotated was measured.

At the same time, a liquid crystal cell having a substrate portion processed by a conventional rubbing method was formed. Further, a liquid crystal cell having a substrate portion having a concavo-convex pattern in which the cross-sectional shape of each concavo-convex pattern was symmetrical was formed on the surface. With respect to these liquid crystal cells, the light transmission characteristics were evaluated in the same manner as above. FIG. 4 shows the relationship between the cell rotation angle and the light transmittance in each liquid crystal cell. In the figure, the horizontal axis represents the cell rotation angle (deg) and the vertical axis represents the light transmittance (au).

From the results shown in FIG. 4, it is suggested that the liquid crystal display element (cell) of the present invention shows the same characteristics as the element processed by the rubbing method with respect to the light transmittance. It can also be seen that the occurrence of defects, defects in displayed images, etc. is reduced.

Further, in a liquid crystal display device having a concavo-convex pattern in which the cross-sectional shapes of the concavities and convexities of the substrate are symmetrical, the phase shift and the contrast of light and dark are low, and the alignment control for the liquid crystal molecules cannot be performed well. I understand.

[0048]

As described above in detail, according to the present invention, the contamination of the substrate, the electrostatic breakdown of each element formed on the substrate, and the like are reduced, the number of defects in the liquid crystal image is very small, and the liquid crystal molecules are small. This is a significant effect in providing a liquid crystal display device in which the alignment uniformity with respect to can be easily achieved.

Further, the liquid crystal display device of the present invention is expected to have a significantly reduced product accident rate in the manufacturing process, and is expected to exhibit excellent performance in various characteristics such as VT characteristics and moving image display state. Its industrial value is great.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of a structure of a pixel portion in a liquid crystal display element of the present invention.

FIG. 2 is a perspective view showing an example of a structure of an alignment film in the liquid crystal display element of the present invention.

FIG. 3 is a diagram showing the relationship between the alignment direction of liquid crystal molecules and the period of the concavo-convex pattern in an example of the liquid crystal display device of the present invention.

FIG. 4 is a diagram showing the relationship between cell rotation angle and light transmittance in cells corresponding to the liquid crystal display elements of the present invention and comparative examples.

[Explanation of symbols]

1, 2 ... Substrate part, 3 ... Liquid crystal, 11, 21 ... Substrate, 12,
22 ... Transparent conductive film, 13, 23 ... Alignment film, a, b ... Horizontal distance of sloping surface of unevenness, d ... One cycle of unevenness, h ... Height of unevenness.

Claims (1)

[Claims] 1. A pair of substrate parts, each of which has a substrate and an alignment film formed of a polymer material that covers the surface of the substrate, and is arranged at a constant distance with the alignment film side as an opposing surface.
A liquid crystal display device comprising a liquid crystal sealed between the pair of substrate portions, wherein each of the substrate portions has a cross section of each unevenness formed by a chemical treatment on the substrate surface and / or the facing surface of the alignment film. That a periodic or aperiodic uneven pattern having an asymmetrical shape is formed, and that the facing surface of each of the substrate portions in contact with the liquid crystal is along the uneven pattern of the substrate surface and / or the facing surface of the alignment film. A liquid crystal display device having a periodic or aperiodic uneven pattern in which the cross-sectional shape of each uneven is asymmetric.