JPH08304829A - Liquid crystal display element and its production - Google Patents

Abstract

PURPOSE: To provide such a method that a rubbing treatment which causes dependence on the visual angle and defects in the product such as display defects or damages in the element can be omitted and by which the rising direction of liquid crystal molecules is determined when voltage is applied, and to provide a liquid crystal display element by using this method. CONSTITUTION: A memory film for polarization of light is formed on at least one transparent substrate. By this method, an orientation treatment in the substrate plane direction is intentionally performed by irradiating with polarized light, while plural perpendicular oriented areas are formed by irradiation of natural light or by heating with laser beams.

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 element and a method for manufacturing the same, and more particularly to a liquid crystal display element which does not require rubbing and can improve a viewing angle and a method for manufacturing the same.

[0002]

2. Description of the Related Art A liquid crystal display device (liquid crystal cell) used for a liquid crystal display or the like is an optical device in which a specific molecular arrangement of liquid crystal is changed to another different molecular arrangement by an external action such as an electric field. The changes in characteristics are used as visual changes for display. In general, in order to bring liquid crystal molecules into a specific alignment state, an alignment treatment is performed on the surface of a glass substrate sandwiching liquid crystal.

In a conventional twisted nematic (TN) type liquid crystal cell or the like, a so-called rubbing method in which a glass substrate sandwiching liquid crystal is unidirectionally rubbed with a glass cloth is used as an alignment treatment. The rubbing direction is such that the rubbing directions of the upper and lower substrates are orthogonal to each other.

When the liquid crystal cell is a negative display, parallel polarizing plates sandwiching the cell are arranged such that their polarization axes are parallel to one of the rubbing directions. In the case of positive display, orthogonally arranged polarizing plates are arranged so that their polarization axes are parallel to the rubbing direction of the adjacent substrate.

[0005]

When rubbing, static electricity due to friction is generated, dielectric breakdown occurs in the alignment film, and alignment failure in that portion may result in defective liquid crystal display. In a liquid crystal cell adopting an active driving method, driving elements and wiring may be destroyed due to static electricity due to rubbing.

Further, a large amount of fine dust is generated during rubbing, and the dust adheres to the substrate due to static electricity, which may cause display defects such as gap defects of liquid crystal cells and black and white dots.

When the alignment treatment is performed by such rubbing, the liquid crystal molecules are pretilted in the rubbing vector direction, that is, the alignment direction. What is pretilt?
For example, as shown in FIG. 8, this is a state in which the liquid crystal molecules have an angle θ with respect to the normal to the substrate surface, that is, a polar angle θ. It can also be said that it has a vertical component orientation. When a voltage is applied in the direction perpendicular to the substrate surface, the liquid crystal molecules that are pretilted rise in the direction of decreasing the polar angle θ shown in FIG.

Since the pretilt occurs only in one direction, which is the rubbing direction, the rising directions of the liquid crystal molecules are aligned when a voltage is applied, and the angle at which the observer can easily see the display is limited to a specific angle range. Therefore, the liquid crystal cell has a viewing angle dependency that it is easy to see from one direction and hard to see from another direction.

As described above, when a liquid crystal cell having a viewing angle dependency is used as a display device, the contrast is extremely lowered at a certain angle with respect to the display screen, and in extreme cases, the brightness of the display is reversed. I will end up.

[0010]

The liquid crystal display element of the present invention comprises a pair of transparent substrates having at least one transparent substrate having a positive alignment structure for aligning liquid crystal molecules parallel to the substrate surface and in a predetermined direction within the substrate surface. A substrate and a liquid crystal layer sandwiched between the pair of substrates are generated, and alignment of liquid crystal molecules having a component in a direction perpendicular to the substrate surface is generated on a part of the substrate surface that has been subjected to the positive alignment treatment. It has a plurality of vertical alignment regions.

Further, the method of manufacturing a liquid crystal display device according to the present invention comprises the steps of forming an alignment film having optical polarization memory characteristics on at least one of a pair of transparent substrates, and irradiating the alignment film with polarized light to form a substrate surface. Forming a vertical alignment region for generating alignment of liquid crystal molecules having a component perpendicular to the substrate surface on the alignment film, and bonding the pair of substrates to each other to form a liquid crystal cell. And a step of injecting a liquid crystal material into the cell.

[0012]

Since the rubbing is not performed, there is no destruction of the element due to the generation of static electricity and no attachment of dust or the like.

The liquid crystal molecules in the vertical alignment region have an alignment component in the vertical direction to the substrate surface even when no electric field is applied.
For example, when a vertically aligned liquid crystal molecule is formed, other liquid crystal molecules in the vicinity thereof are aligned under the influence of the vertically aligned liquid crystal molecule so as to have a tilt in a polar angle direction.

When a voltage is applied between the liquid crystal cells, first, the liquid crystal molecules having the inclination in the polar angle direction rise with one side of the liquid crystal molecules already lifted up. That is, the rising direction is determined by the polar angle of the liquid crystal molecules. Then, the liquid crystal molecules aligned only in the horizontal direction around the periphery also rise along the direction of the liquid crystal molecules that have risen earlier.

[0015]

EXAMPLES 1) Alignment Method Using Optical Polarization Memory Film As an alignment method for liquid crystal molecules that does not use the conventional rubbing method, an alignment method using an optical polarization memory film has been proposed.
For example, the following examples of optical polarization memory films have been published: (1) Using a diazoamine dye-doped silicon polyimide: Wayne M .; Gibbons
Others, NATURE Vol. 351 (1991) p. Four
9, (2) Using PVA (polyvinyl alcohol) doped with an azo dye: Yasufumi Iimura et al .: 18th Liquid Crystal Symposium-The 64th Annual Meeting of the Chemical Society of Japan-, p. 34, Published September 11, 1992, The Chemical Society of Japan. Or
Jpn. J. Appl. Phys. Vol. 32 (19
93) pp. L93-L96, (3) with photopolymerized photopolymers: Martin Schatt et al., J.
pn. J. Appl. Phys. Vol. 31 (199
2) pp. 2155-2164.

The applicant of the present invention also discloses that in the specification of Japanese Patent Application No. 5-326990 filed on Dec. 24, 1993, an optical polarization memory film is formed on a substrate surface, and a large number of pixels are formed in one pixel. Adopts a multi-domain structure that includes domains, performs a positive alignment process for each micro area of the multi-domain, and forms an orientation in a certain direction in each micro area, while realizing a random orientation for the entire multi-domain The method of doing is disclosed.

When the optical polarization memory film as described above is used, there is no one-way pretilt of liquid crystal molecules that occurs during rubbing. Therefore, when no voltage is applied, the liquid crystal is arranged horizontally along the substrate surface. Even when the multi-domain is subjected to the random alignment treatment, it only has the random alignment in the in-plane direction of the substrate.

When the pretilt does not exist in this way, when a voltage is applied between the substrates of the liquid crystal cell, the rising directions of the liquid crystal molecules are not fixed, but rise in different directions. In some cases, the rising direction may be uneven depending on the location, or the rising direction may not be stable.

Even if a random positive alignment treatment is performed in the in-plane direction of the substrate, if the rising direction when a voltage is applied is not controlled, the rising direction of the liquid crystal tends to be biased, and the randomness of the alignment direction can be guaranteed. It disappears, and the viewing angle dependence occurs.

2) Control of rising direction of liquid crystal molecules In the following, when the alignment treatment is performed using the optical polarization storage film, the viewing angle dependence is controlled by controlling the rising direction of the liquid crystal molecules when the liquid crystal cell voltage is applied. An embodiment of a method of manufacturing a liquid crystal display device that eliminates the above will be described.

In the method of manufacturing a liquid crystal display device, 1) a step of forming a transparent electrode, a driving element and the like on a transparent substrate, 2) a step of performing an alignment treatment on the transparent substrate, 3) a pair of glass substrates as spacers Step of forming a liquid crystal cell by sandwiching the same, 4)
A liquid crystal injection step, and 5) sealing step and the like are included. Here, the steps 2), 3), and 4) of the above manufacturing process will be mainly described.

In addition, generally used methods may be used for the step 1) of forming the transparent electrode and the driving element on the transparent substrate and the step 5) of sealing. As a driving method, any of a simple matrix type, a TFT (thin film transistor) type, an MIM and the like may be used.

Alignment treatment on transparent substrate-in-plane direction of substrate
The step of performing the positive alignment treatment in the in-plane direction of the substrate by using the optical polarization storage film on the transparent substrate will be described.

The light polarization memory film used is, for example, polyvinyl cinnamate. After applying this optical polarization memory film to one of the pair of transparent substrates, or both substrate surfaces,
Orients the optical polarization memory film.

For example, the orientation is formed so that the orientation is uniform in each micro domain (micro area), and the orientation is random for the macro domain. An example of the orientation to be formed is shown in FIG. The vertical lines, horizontal lines, and arrows shown in the figure indicate the orientation directions, respectively.

For example, as shown in FIG. 2 (A), four quadrangular minute regions 1a, 1 having different orientations of 90 degrees each.
b, 1c, and 1d are combined to form one unit, and a large number of unit regions are arranged on the entire surface of the optical polarization storage film without a gap. Also, FIG.
As shown in (B), the hexagonal minute region 1e may be formed on the optical polarization storage film without a gap. The shape of the minute region may be any shape such as a quadrangle, a hexagon, a triangle, and a diamond shape as long as it can be formed on the film surface without a gap.

The size of each micro area is set to include a large number of micro areas per pixel. For example, several to several tens of minute regions are included in an area of about 100 × 300 μm, which is a typical size of one pixel. Figure 2
In the case of forming a multi-domain by using four minute regions as a unit as shown in (A), it is desirable to form one or a plurality of unit regions in one pixel.

As a method for forming the orientation, for example, FIG.
An optical system as shown in is used. The laser output from the laser light source 2 is narrowed down by an optical system (including, for example, an aperture having a predetermined shape and a lens) 3 to obtain a predetermined beam spot diameter in which the polarization characteristic is eliminated.

Further, the laser beam is passed through a polarizing plate 4 having a polarization axis in a predetermined direction to obtain linearly polarized laser light 5. The linearly polarized laser light 5 is applied to a predetermined minute area on the optical polarization storage film formed on the transparent glass substrate 6. A micro domain having the size of the irradiation beam spot diameter can be formed. XY move the movable stage 7 while rotating the polarization direction.
By moving in the direction, an alignment direction corresponding to the polarization direction can be formed, and a predetermined multi-domain can be formed on the entire surface of the substrate.

It is to be noted that the laser beam is expanded and the orientation of a plurality of minute regions is set to 1 by passing through a polarizing plate having a different polarization direction for each micro domain such as a kind of photomask.
It is also possible to form them all at once by irradiation.

Alignment Treatment on Transparent Substrate-Vertical Alignment Area
When polyvinyl cinnamate is used as a light polarization memory film, when the light polarization memory film is heated to a temperature of 200 ° C. or higher by irradiation with light having a local heating effect such as laser light or other heating means, It has been confirmed by experiments by the applicants that the alignment state of the portion is released and the liquid crystal molecules arranged therein are vertically aligned.

It has also been confirmed by experiments that a vertical alignment region is similarly formed when natural light (random polarization) is vertically irradiated to the optical polarization storage film. In this case, the vertical alignment region may be formed by arranging the side chains in the polarization memory film in the vertical direction by natural light irradiation.

A vertical alignment region is formed in the optical polarization storage film by using any one of the above methods. For example, in the case of performing laser irradiation, the device shown in FIG. 3 used for the orientation processing of the optical polarization storage film can also be used. In this case, the polarizing plate 4 may be removed and used in a non-polarized state.

As will be mentioned later, one vertical alignment region affects the rising direction of the liquid crystal molecules in the radius of several tens to several hundreds of μm centering on this region, and therefore, the same spacing or the same interval as this. The vertical alignment regions may be formed at narrower intervals. It is preferable that the vertical alignment regions exist with equal probability, and it is preferable that the number of vertical alignment regions formed per pixel is made uniform.

The place to be formed may be basically any place. However, if there is a vertical alignment region, the polar angle direction of the liquid crystal molecules will change with that region as the center or boundary, so it is preferable to form the vertical region at the boundary of the minute regions aligned from the beginning. If not formed on the boundary, the boundary of the alignment newly created by forming the vertical region should equally divide the alignment region.

For example, four 9's as shown in FIG.
As an example of an alignment method in which a plurality of quadrangular minute regions each having a different orientation direction by 0 degree are combined and arranged as one unit, as shown by α in FIG. A vertical alignment region is formed at the intersection of the region boundaries. Alternatively, as shown by β in FIG. 1B, a linear vertical region is formed on the boundary of each of the four minute regions. Similarly, in the case of a micro domain other than a quadrangle, a minute vertical region can be formed at the intersection of the boundaries of a plurality of micro domains, or a vertical region can be formed on the boundary of the micro domains.

The size of the alignment region is not particularly limited, but it seems that one molecule or several molecules of liquid crystal may be vertically aligned in this region. Of course, when the vertical alignment region is formed on the boundary of the micro domain, it is sufficient that one molecule or several molecules of the liquid crystal be aligned in a row.

Liquid crystal cell formation and liquid crystal injection step After the alignment treatment step for the optical polarization storage film, two substrates to be paired are arranged to face each other with a gap material sandwiched between them, and an injection port is provided to bond them at the end. Form a liquid crystal cell.

As the liquid crystal material, a liquid crystal in which a nematic liquid crystal material is mixed with chiral molecules is used. For example, as the liquid crystal material, ZL1-2392 (manufactured by Merck), SR
-5003 (manufactured by Chisso Corporation), and as a chiral material, S-
811 (manufactured by Merck) is used.

When a TN-LCD (liquid crystal display element) in which liquid crystal molecules are twisted by 90 ° between opposing substrates is used, the chiral pitch of the chiral nematic liquid crystal is set to p.
And the thickness of the liquid crystal layer sandwiched between the glass substrates is d
Then, the chiral pitch d and the liquid crystal layer thickness d should be set so that d / p = 0.25 is satisfied.

The optical rotatory power is not limited to 90 degrees, and it is 0
The values of p and d may be selected so that ≤d / p≤0.75. As shown in FIG. 4, the injection port 17 is immersed in the liquid crystal material 9 contained in the container 14. For example, the substrate 11 has the common electrode 15 and the optical polarization storage film 16 formed thereon, and the other substrate 10 has the TFT element 12 and the pixel electrode 13 formed thereon.

The liquid crystal material 9 is injected between the substrates 10 and 11 by using a capillary phenomenon or the like. At the time of injecting the liquid crystal, the liquid crystal material 9 is heated from both sides by heating devices 18 and 19 such as heaters to a temperature equal to or higher than the phase transition temperature (NI point) between the nematic phase and the isotropic phase of the liquid crystal. For example, when the above liquid crystal material ZL-2392 is used, 105 ° C.
(N-I point) or more. The liquid crystal molecules 8 in the liquid crystal material 9 are in an isotropic state. It should be noted that if the liquid crystal cell is preliminarily heated in an empty state before liquid crystal injection using the heating devices 18 and 19, the isotropic state can be more surely ensured.

For the temperature control of the liquid crystal, a temperature control technique can be used in which a temperature detector is placed in the liquid crystal material 9 and the current amount of the heaters 18 and 19 is adjusted while monitoring the temperature. Temperature control can be manual or automatic.

After the liquid crystal material is injected, the amount of heat generated by the heating devices 18 and 19 is reduced, and the liquid crystal material 9 is gradually cooled. The temperature is controlled so that the cooling rate is in the range of 0.1 to 10 ° C./minute, for example, 0.5 ° C./minute. When cooled to the phase transition temperature (N-I point) at this speed, the liquid crystal material 9
Initially has an isotropic (I) state, but undergoes a phase transition to a nematic liquid crystal (N) state.

Since the alignment structure is formed on at least one of the substrates, the liquid crystal molecules are aligned in the alignment direction on the alignment surface and twisted in the thickness direction according to the chiral pitch. Although the example of forming the multi-domain type liquid crystal display element having the vertical region has been described above, the liquid crystal material need not always be heated at the time of injection as described above and may be injected in a nematic state at room temperature. Further, in the case where the alignment treatment is performed on both surfaces of the pair of substrates and the directions of the corresponding alignments are deviated by 90 °, the liquid crystal in the isotropic state as described above or the chiral pitch is injected. It is not necessary to adjust the mixing amount of the chiral agent so as to match the twist angle with.

However, in the case of injecting the liquid crystal in the nematic state into the one in which only one of the substrates has been subjected to the alignment treatment, the flow pattern due to the flow alignment at the time of injection remains as it is, and the display quality is remarkably deteriorated. is there. Therefore,
After the injection of the liquid crystal material, it is necessary to release the flow pattern by releasing the bonding state at the interface between the alignment film and the liquid crystal phase, applying energy to enable the free movement of the liquid crystal molecules.
For example, after injecting the liquid crystal material, if the liquid crystal cell is heated to a temperature higher than the NI point, and without changing the chemical properties of the optical polarization storage film and below a predetermined temperature that does not exceed the decomposition temperature of the liquid crystal material, the flow pattern disappears. be able to. Besides heating, energy can be applied by irradiation with a magnetic field, light irradiation, ultrasonic vibration, or the like.

3) Alignment state of liquid crystal molecules Alignment of liquid crystal molecules when no voltage is applied Alignment of liquid crystal molecules when no voltage is applied (when an electric field is not applied between liquid crystal cells) of the liquid crystal display device formed by the above method The state will be described. When the vertical alignment region is formed at the intersection of the boundaries of the four minute alignment regions as shown in FIG. 1A, the liquid crystal molecules are formed as shown in FIG.
It is considered that the orientation state shown in FIG.

FIGS. 5A and 6A are sectional views taken along the line indicated by the chain line aa 'in FIG. 1A. The “portion irradiated with natural light” shown in the figure corresponds to the portion subjected to the vertical alignment treatment. Both figures show the case where the positive alignment process and the vertical alignment region are formed using the optical polarization storage film on only one of the pair of substrates.

The liquid crystal molecules in the vertical alignment region are aligned in the direction perpendicular to the substrate surface, and the other liquid crystal molecules are originally aligned only in the horizontal direction (in-plane direction of the substrate). However, since the liquid crystal molecules have an elongated shape, they are easily affected by the arrangement of adjacent liquid crystal molecules and tend to be aligned in the same arrangement direction. For this reason, as shown in FIG. 5A, the liquid crystal molecules in the vicinity of the vertical alignment region are influenced by the vertically aligned liquid crystal molecules, and are aligned to a certain degree in the vertical direction. That is, it has a tilt in the polar angle direction.

As the distance from the vertically aligned liquid crystal molecules is reduced, the influence becomes weaker, and the liquid crystal molecules exhibit a nearly horizontal alignment state. Empirically, the liquid crystal molecules located at a position several μm away from the liquid crystal molecules aligned in the vertical direction are considered to be the alignments in the in-plane direction of the substrate without the vertical component.

The polar angle direction of the liquid crystal molecules in the vicinity of the vertical alignment treatment region is different between FIG. 5A and FIG. 6A, but this is different from the alignment direction in each microdomain formed in the plane of the substrate. It seems to be determined by the balance of.

5B to 5D and 6B to 6D are, in the thickness direction of the liquid crystal cell, in the vicinity of the substrate surface subjected to the multi-domain alignment treatment, in the cell center, and without the alignment treatment. It shows the liquid crystal directors of the liquid crystal molecules on the horizontal plane at three points near the substrate surface. In addition, the arrow shown in the drawing indicates the rising side of the liquid crystal molecule, that is, the tilt-up direction of the liquid crystal molecule, and this arrow direction is hereinafter referred to as a liquid crystal director. Further, the drawing shown here corresponds to the case of a TN type liquid crystal display element.

For example, as shown in FIG. 5D, the liquid crystal molecules on the alignment processing side on the optical polarization memory film are 90 in each minute region.
In the case of having different counterclockwise liquid crystal directors, the liquid crystal molecules in each of the four micro regions are directed toward the center where vertical alignment processing is performed, as shown in FIG. 5C. As shown in FIG. 5B, the liquid crystal molecules on the side of the substrate that has not been subjected to the alignment process are clockwise directors whose alignment directions are different from those of the liquid crystal molecules on the substrate on which the alignment process is performed by 90 degrees.

Alternatively, as shown in FIG. 6D, when the liquid crystal molecules in the vicinity of the alignment film have clockwise directors that are different by 90 ° in each region, the liquid crystal molecules in the center of the cell are shown in FIG. 6C. As shown in the figure, the liquid crystal molecules in each of the four minute regions show directors that go outward from the center where the vertical alignment processing is performed, and the liquid crystal molecules on the substrate where the alignment processing is not performed are shown in FIG. As shown in B), liquid crystal molecules show counterclockwise directors that differ by 90 ° in each region. Of course, it may be in any orientation.

As described above, the liquid crystal molecules are aligned in the horizontal azimuth direction and the polar angle direction on the substrate by the in-plane alignment treatment performed on the entire surface of the optical polarization memory film and the vertical alignment treatment partially performed. Have.

Alignment Direction of Liquid Crystal Molecules when Voltage is Applied FIG. 7 shows the alignment state of the liquid crystal molecules when a voltage is applied between the cells of the liquid crystal display device having the alignment state shown in FIG. Is.

Liquid crystal molecules adjacent to the vertical alignment region at the center of the cell and having a large degree of inclination in the polar angle direction (small polar angle) start rising at a low voltage. The rising direction depends on the polar angle direction and rises with one side of the liquid crystal molecule already lifted up. When the liquid crystal molecules adjacent to the vertical alignment region rise, the liquid crystal molecules around these liquid crystal molecules are also affected by the rise, and start to rise along the direction of the liquid crystal molecules that have already risen. continue,
Liquid crystal molecules in a region having a radius of several tens to several hundreds μm from the vertical alignment region rise in the same direction one after another.

The liquid crystal molecules having a vertical component alignment direction when no voltage is applied are present only in a region having a radius of several μm or less from the liquid crystal molecules aligned in the vertical direction, but the liquid crystal molecules in a wider region. The rising direction of the molecule is determined by the influence of the vertically aligned liquid crystal molecule.

By thus forming the vertical alignment region and applying a vertical alignment component to some of the liquid crystal molecules when no voltage is applied, the rising direction of the liquid crystal molecules on the entire substrate when voltage is applied is stabilized. Can be generated.

The vertical alignment regions are arranged evenly over the entire surface of the substrate so that the azimuth directions of the liquid crystal molecules having the alignment component in the vertical direction are present in the entire substrate without any deviation and at equal probability. If adjusted, it is possible to obtain a good display that does not depend on the viewing angle.

In the above-described embodiments, the example in which the vertical alignment region is formed only on one substrate surface has been mainly described, but the vertical alignment region may be formed on both substrate surfaces. However, if the influences of the vertical alignment regions formed on the respective substrates conflict with each other on the upper and lower substrates, the rising direction of the liquid crystal molecules in the center of the cell may become unstable. Rather, it is possible to define a stable rising direction by forming the vertical alignment region on only one surface, and the number of steps can be reduced.

Further, in the above-mentioned embodiment, the vertical alignment region is formed after the alignment treatment of the optical polarization memory film is performed.
The same effect can be expected by forming the vertical alignment region first and then performing the alignment treatment of the optical polarization storage film.

Even if the optical polarization storage film is not subjected to any alignment treatment, or even if it is aligned in only one direction, the vertical alignment regions are uniformly formed at appropriate intervals, and liquid crystal molecules are formed. It is possible to obtain the effect of defining the rising direction of the, and stabilizing the viewing angle characteristics.

The liquid crystal molecules in the vertical alignment region do not necessarily have complete vertical alignment (polar angle is 0 when no voltage is applied).
However, if it has a vertical alignment component, it similarly has the effect of defining the rising direction of liquid crystal molecules in the vicinity.

The present invention has been described above with reference to the embodiments.
The present invention is not limited to these. For example,
It will be apparent to those skilled in the art that various modifications, improvements, combinations, and the like can be made.

[0066]

As described above, according to the present invention,
Various problems due to dust and static electricity generated by rubbing treatment can be solved. Further, the rising direction of liquid crystal molecules is defined, and uniform and isotropic viewing angle characteristics can be provided over the entire cell surface.

[Brief description of drawings]

FIG. 1 is an enlarged view showing an alignment treatment state of liquid crystal molecules according to an example.

FIG. 2 is an enlarged view showing a state of alignment treatment on a light polarization memory film according to an example.

FIG. 3 is a perspective view of an apparatus for performing an alignment treatment on an optical polarization storage film according to an example.

FIG. 4 is a cross-sectional view of an apparatus for manufacturing a liquid crystal display element according to an example.

FIG. 5 is an enlarged view showing an alignment treatment state of liquid crystal molecules according to an example.

FIG. 6 is an enlarged view showing an alignment treatment state of liquid crystal molecules according to an example.

FIG. 7 is an enlarged view showing an alignment treatment state of liquid crystal molecules according to an example.

FIG. 8 is an enlarged view showing a liquid crystal molecule having a pretilt.

[Explanation of symbols]

 1a, 1b, 1c, 1d, 1e Micro area 2 Laser light source 3 Optical system 4 Polarizing plate 5 Linearly polarized laser light 6 Transparent glass substrate 7 Movable stage 8 Liquid crystal molecule 9 Liquid crystal material 10, 11 Glass substrate 12 Element 13 Pixel electrode 14 Container 15 transparent electrode 16 light polarization memory film 17 liquid crystal injection port 18, 19 heating device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuo Toko 1-3-1 Eda Nishi, Aoba-ku, Yokohama-shi, Kanagawa Stanley Electric Co., Ltd. (72) Inventor Takashi Sugiyama 1-Eda Nishi, Aoba-ku, Yokohama-shi, Kanagawa 3-1 In Stanley Electric Co., Ltd. (72) Inventor Toru Hashimoto 1-3-1 Eda Nishi, Aoba-ku, Yokohama-shi, Kanagawa Inside Stanley Electric Co., Ltd. (72) Inoue Susuke 3-13 Nishi-izumi, Nerima-ku, Tokyo 40 (72) Inventor Yasufumi Iimura 2-8-34 Miyato, Asaka City, Saitama Twin Howe Slime 201

Claims (20)

[Claims] 1. A pair of transparent substrates having at least one transparent substrate having a positive alignment structure for aligning liquid crystal molecules parallel to the substrate surface and in a predetermined direction in the substrate surface, and sandwiched between the pair of substrates. A liquid crystal display device having a liquid crystal layer, and having a plurality of vertical alignment regions for generating alignment of liquid crystal molecules having a component perpendicular to the substrate surface, in a part of the substrate surface having the positive alignment structure. 2. The liquid crystal display element according to claim 1, wherein the positive alignment structure is formed on a light polarization memory film. 3. The liquid crystal display device according to claim 1, wherein one or more vertical alignment regions are provided for each region having a radius of several tens to several hundreds of μm. 4. The liquid crystal display device includes a large number of pixels,
4. The liquid crystal display device according to claim 1, wherein the size of the vertical alignment region is sufficiently smaller than the size of one pixel, and each pixel has the same number of the vertical alignment regions. 5. The liquid crystal display device according to claim 1, wherein the positive alignment structure has a large number of minute regions having different alignment directions in the plane of the substrate. 6. The positive orientation structure according to claim 1, wherein a large number of minute regions are formed by the positive orientation structure, and the orientation directions in the plane of the substrate are present with equal probability in all directions as a whole. Liquid crystal display device. 7. The positive orientation structure has a large number of units, each of which has four adjacent minute regions whose orientation directions are deviated from each other by 90 °, 180 ° or 270 ° as one unit. 7. The liquid crystal display device according to any one of items 6 to 6. 8. The liquid crystal display element according to claim 1, wherein the vertical alignment region is present at a boundary between minute regions having different alignment directions in the plane of the substrate. 9. The liquid crystal display device according to claim 1, wherein the vertical alignment region exists at an intersection of boundaries of minute regions having different alignment directions. 10. The azimuth directions of liquid crystal molecules, in which the vertical alignment regions are arranged substantially evenly in the plane of the substrate and have a vertical alignment component, are evenly distributed in all directions in the entire substrate with equal probability. The liquid crystal display element according to claim 1. 11. The liquid crystal layer contains a chiral nematic liquid crystal, and when the chiral pitch of the chiral nematic liquid crystal is p and the thickness of the liquid crystal layer between the pair of transparent substrates is d, the value of d / p is The liquid crystal display element according to claim 1, wherein the liquid crystal display element has a thickness of 0 to 0.75. 12. The liquid crystal display device according to claim 1, wherein the other substrate facing the transparent substrate that has been subjected to the positive alignment treatment is not subjected to the alignment treatment. 13. The liquid crystal display device according to claim 1, wherein the other substrate facing the transparent substrate that has been subjected to the positive alignment treatment is also subjected to the positive alignment treatment. 14. The liquid crystal display device according to claim 1, wherein the vertical alignment region is provided only on one transparent substrate. 15. A step of forming an alignment film having optical polarization memory characteristics on at least one of a pair of transparent substrates, a step of irradiating the alignment film with polarized light to form an in-plane orientation of the substrate, A step of forming, on the alignment film, a vertical alignment region for generating alignment of liquid crystal molecules having a component in a direction perpendicular to the substrate surface; a step of bonding the pair of substrates to form a liquid crystal cell; And a step of injecting a liquid crystal material into the liquid crystal display element. 16. The step of forming the vertical alignment region comprises:
The method for manufacturing a liquid crystal display element according to claim 15, further comprising heating a predetermined region of the alignment film to 200 ° C. or higher. 17. The step of forming the vertical alignment region comprises:
The method for manufacturing a liquid crystal display device according to claim 15, further comprising irradiating a predetermined region of the alignment film with laser light. 18. The step of forming the vertical alignment region comprises:
The method for manufacturing a liquid crystal display element according to claim 15, comprising irradiating a predetermined region of the alignment film with natural light. 19. The step of injecting the liquid crystal material comprises N-
The method for manufacturing a liquid crystal display element according to claim 15, further comprising injecting a liquid crystal material heated to a temperature of point I or higher. 20. The step of injecting the liquid crystal material is an step of injecting liquid crystal in a nematic state, and after this step, the bonded state between the liquid crystal molecule and the surface of the substrate is released to allow free movement of the liquid crystal molecule. 20. The method for manufacturing a liquid crystal display element according to claim 15, further comprising the step of applying energy that enables the above.