JP3068376B2 - Manufacturing method of liquid crystal display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to tilt angle control in a method for manufacturing a liquid crystal display. In particular, the present invention is a technique capable of manufacturing a liquid crystal display device having an arbitrary viewing angle characteristic with good controllability, and by forming alignment states having different tilt angles in the same liquid crystal cell,
The present invention relates to a novel alignment control method that enables regions having different viewing angle characteristics to be formed at arbitrary positions.

[0002]

2. Description of the Related Art A liquid crystal display (LCD) is a display device that changes the orientation of liquid crystal molecules in a liquid crystal cell between a pair of substrates and uses the resulting change in the optical refractive index in the liquid crystal cell. . Therefore, it is important that the liquid crystal molecules in the liquid crystal cell are initially arranged as regularly as possible. In order to arrange the liquid crystal molecules regularly in this manner, the surface state of the substrate sandwiching the liquid crystal cell regulates the interaction of the liquid crystal molecules.

The most widely used method for initially aligning liquid crystal molecules in a certain direction is to apply a liquid crystal alignment film material to opposing surfaces of a pair of substrates, and dry and cure the applied material. After the formation of the film, the surface of the alignment film is rubbed.

There are two types of alignment films for regulating the alignment of the liquid crystal: an inorganic alignment film and an organic alignment film. Examples of the material of the inorganic alignment film include an oxide, an inorganic silane, a metal, and a metal complex. Examples of the material for the organic alignment film include polyimide. A typical example of a liquid crystal alignment film material currently used is a polyimide resin. Polyimide resin is formed by applying a polyamic acid which is a precursor of a wholly aromatic polyimide (a wholly aromatic PI) to a substrate, and then causing a polyimide reaction by heating, thereby converting the polyamic acid into a polyimide resin. You. The reason why polyimide resin is widely used as a liquid crystal alignment film material is that it has good solubility in the state of polyamic acid, so that concentration and mucous membrane can be easily prepared, coating properties are good, and film thickness control. Is easy. The produced polyimide resin is more energetically stable than polyamic acid, and does not cause a reversible reaction even when washed with water.

By subjecting the polyimide film thus formed on the substrate to a rubbing treatment with a polishing cloth or the like, the liquid crystal molecules can be oriented along the rubbing direction.
Since the rubbing process is performed in a uniform direction on the substrate, all the tilt angles, ie, pretilt angles, of the liquid crystal molecules in contact with the alignment film in the liquid crystal cell become uniform. Therefore, the pretilt angles are substantially the same in each picture element constituting the unit dot of the matrix display pattern.

An active matrix type liquid crystal display device (TFT) using a thin film transistor as a switching element connected to each picture element electrode serving as one picture element of a display pattern
-LCD) adopts a configuration of a twisted nematic (TN) type liquid crystal cell (TN mode liquid crystal display device). According to the configuration of the liquid crystal cell, the liquid crystal molecules move between the pair of substrates along the direction perpendicular to the substrate surface.
It is oriented to be twisted by 0 °. In the viewing angle characteristics of the liquid crystal display device, an optimum viewing angle azimuth and a viewing angle range are determined according to the orientation (alignment direction and tilt angle) of liquid crystal molecules in the liquid crystal layer.

[0007]

In a twisted nematic type liquid crystal display device, since a liquid crystal molecule has anisotropic refractive index (birefringence), a human (observer) liquid crystal display device is viewed. The phenomenon that the contrast changes depending on the angle occurs. Generally, in a normally white mode liquid crystal display device in which light is transmitted when a voltage is not applied and a white display is performed, a voltage is applied between driving electrodes formed on both substrates of a liquid crystal cell, and a voltage is applied to a substrate surface. When the liquid crystal display device is viewed from a vertical direction, as shown by a solid line L1 in FIG. 12, the light transmittance decreases as the applied voltage value increases. When the value is saturated, the transmittance becomes almost zero,
Even if the applied voltage is further increased, the transmittance remains almost zero. However, the applied voltage-transmittance characteristic indicated by the solid line L1 in FIG. 12 changes due to a change in the viewing angle direction for observing the liquid crystal display screen. This will be described with reference to FIGS.

FIGS. 13 and 14 are a perspective view and a cross-sectional view of a liquid crystal cell sandwiched between a pair of substrates 31 and 32, respectively. In these figures, one substrate 31 has a glass substrate 31a, a transparent electrode 31b, and an alignment film 31c, and the other substrate 32 has a glass substrate 32a, a transparent electrode 32b, and an alignment film 32c. . The liquid crystal molecules 35 in the liquid crystal cell are twisted 90 ° between the substrates 31 and 32. 13 and 14, the symbol δ indicates the pretilt angle, and the number 36 indicates the normal viewing angle direction 36.
When a voltage is applied to the liquid crystal cell and the viewing angle is inclined in the normal viewing direction 36 from a direction perpendicular to the substrate surface, the applied voltage-transmittance characteristic changes as shown by a solid line L2 in FIG. I do. That is, a phenomenon occurs in which the transmittance decreases to some extent as the applied voltage increases, then increases again when the voltage exceeds a specific voltage value, and then gradually decreases again. Therefore, when the viewing angle is inclined in the normal viewing direction 36, a phenomenon occurs in which the black and white (negative or positive) of the image is inverted at a specific angle (this phenomenon is called an inversion phenomenon). This is a phenomenon that occurs because the liquid crystal molecules in the liquid crystal layer are inclined with a tilt angle, and the refractive index changes depending on the viewing angle. This phenomenon is a major obstacle for the viewer of the image. This will be described with reference to FIG. 15. As shown in FIG. 15A, when the applied voltage is zero or a relatively low voltage, the observer 3 positioned in the normal viewing angle direction
In FIG. 7, the central molecule 35 in the liquid crystal layer looks elliptical, but when the applied voltage is gradually increased, the central molecule 35 is arranged so that its major axis is aligned with the direction of the electric field, that is, the direction perpendicular to the substrate surface. Move. Therefore, as shown in FIG. 15B, the observer 37 has a moment when the central molecule 35 looks like a perfect circle. When the voltage is further increased, the central molecule 35 becomes substantially parallel to the direction of the electric field, and as shown in FIG.

In a similar phenomenon, even in a viewing angle direction other than the normal viewing angle direction 36, even if the reversal phenomenon does not occur due to the difference in transmittance-voltage characteristics, the black-and-white contrast ratio is increased by increasing the viewing angle. It has a viewing angle characteristic of being lowered.

In a TN mode liquid crystal display device, the reversal phenomenon observed in the normal viewing angle direction is a great obstacle for a viewer, and results in deteriorating the display characteristics of the liquid crystal display device itself.

As a technique for improving a phenomenon peculiar to the TN mode liquid crystal display device, there is a technique disclosed in Japanese Patent Laid-Open No. 2-12. This technology divides the display electrodes that make up one pixel in an active matrix liquid crystal display device, and changes the electric field conditions applied to the liquid crystal molecules corresponding to the inner electrode and the liquid crystal molecules corresponding to the outer electrode. This is to improve the viewing angle characteristics.

However, this technique has a drawback that the manufacturing process becomes complicated and the driving method becomes complicated because it is necessary to change the electrode pattern itself.

It is hard to say that the effect of improving the viewing angle characteristics is also sufficient.

Also, JAPAN DISPLAY '92
For p591 to p594 and p886, after rubbing the surface of the alignment film in one direction, a part of the surface is covered with a resist, and rubbing is performed in a direction opposite to the rubbing direction previously performed.
Then, the resist is removed, and if the pretilt angle is different by giving the alignment film an alignment characteristic based on the difference in the rubbing direction between the surface of the alignment film coated with the resist and the surface of the alignment film not coated with the resist. A method of forming a plurality of pre-tilt angles corresponding to each material on the surface of the alignment film by rubbing with juxtaposing polyimide alignment films of different materials is disclosed.

However, when a resist is coated on the surface of the alignment film, the alignment regulating force on the surface of the alignment film is significantly deteriorated, and in the case of forming a polyimide alignment film of a different material, the patterning of the alignment film is complicated. These methods are not practical because they are steps.

It is an object of the present invention to effectively control the viewing angle characteristics of a liquid crystal display device which causes such a serious problem.
An object of the present invention is to provide a wide-viewing-angle liquid crystal display device with improved display quality at low cost by providing a method of manufacturing a liquid crystal display device that can be improved.

[0017]

According to a method of manufacturing a liquid crystal display device of the present invention, a liquid crystal display device in which a liquid crystal layer is sandwiched between a pair of substrates and picture elements are arranged in a matrix is provided. Forming a film that serves as an alignment film for controlling the alignment of the liquid crystal layer on at least one of the substrates, and irradiating the film with light to control the pretilt angle of liquid crystal molecules, and includes a step of imparting orientation properties,
A region having a different pretilt angle is formed in the substrate, and a pair of
A region with a large pretilt angle and a region with a small pretilt angle
By combining them, the alignment state can be changed
A method for manufacturing a liquid crystal display device , wherein the liquid crystal display device is formed in a direction, whereby the above object is achieved.

In one embodiment, the film is irradiated with the light by selectively defining an area with respect to a desired area of the film, and the pre-tilt angle of the light-irradiated area is different from that of the non-light-irradiated area. And rubbing to impart orientation characteristics.

In one embodiment, the light-irradiated area or the non-light-irradiated area is formed in units of the picture elements.

In one embodiment, the light irradiation region is formed by irradiating light with different light intensities between picture elements.

In one embodiment, light is irradiated such that a light irradiation portion and a non-light irradiation portion are mixed in one picture element.

In one embodiment, the light irradiating unit is irradiated with light so that the light irradiating unit in one picture element has a different light intensity.

In one embodiment, the method includes a step of forming a film to be an alignment film on both of the pair of substrates, and a step of irradiating at least one of the films with light to control a pretilt angle of the film. I do.

In one embodiment, when selectively irradiating the film with the light, a mask or a means for condensing the light is used.

In one embodiment, the film comprises an organic polymer.

In one embodiment, a material mainly composed of polyimide, polyamide, polystyrene, polyamide imide, epoxy acrylate, spirane acrylate, or polyurethane is used as the organic polymer film.

In one embodiment, an inorganic oxide film, an inorganic nitride film, an inorganic fluoride film, or a metal film is formed as the film.

In one embodiment, the light is one of ultraviolet light, visible light, or infrared light, or laser light having a wavelength corresponding to these lights.

In one embodiment, the light is either ultraviolet light or laser light of this wavelength.

According to a method of manufacturing a liquid crystal display device of the present invention, in a method of manufacturing a liquid crystal display device in which a liquid crystal layer is sandwiched between a pair of substrates and picture elements are arranged in a matrix, at least one of the pair of substrates is provided. Forming a film that becomes an alignment film for controlling the alignment of the liquid crystal layer, performing a first surface treatment on the film to give an alignment direction of the liquid crystal layer, and forming the liquid crystal layer on a part of the film. To give the unevenness that determines the pretilt angle of the second
Includes a step of performing a surface treatment, pretilt in the substrate
To form pre-tilt between a pair of substrates.
Combining large and small areas
That is, a method for manufacturing a liquid crystal display device in which an alignment state is formed in an arbitrary region in an arbitrary direction, thereby achieving the above object.

In one embodiment, the second surface treatment includes:
Selectively apply one picture element as a unit. In one embodiment, the second surface treatment is performed so that the size of the unevenness differs between picture elements.

In one embodiment, the second surface treatment is selectively applied to a plurality of portions in one picture element. In one embodiment, the second surface treatment is performed so that the size of the unevenness is different in a plurality of portions in the picture element.

In one embodiment, the second surface treatment comprises:
This is performed by bringing a solution containing either an acid or an alkali as a main component into contact with the surface of the film.

In one embodiment, the second surface treatment is performed by contacting one of a reactive gas and a gas in a plasma state with the surface of the film.

According to a method of manufacturing a liquid crystal display device of the present invention, in a method of manufacturing a liquid crystal display device in which a liquid crystal layer is sandwiched between a pair of substrates and picture elements are arranged in a matrix, at least one of the pair of substrates is provided. Forming a base film, forming an uneven shape on the base film, forming a film that covers the base film and serving as an alignment film for controlling alignment of the liquid crystal layer, and forming the uneven shape on the film. a step of transmitting to encompass the step of applying the alignment direction of the liquid crystal layer to the membrane, the uneven shape on the lower ground layer
The process of forming is selectively applied to a plurality of parts in one picture element
Thus, regions having different pretilt angles are formed,
Between large and small pretilt angles between substrates
By combining them, the alignment state can be set in any area
Forming a liquid crystal display device in the direction of ,
Thereby, the above object is achieved.

In one embodiment, the step of forming the irregularities on the base film includes the step of forming the first irregularities on the base film and the step of forming the first irregularities on the base film. Selectively forming a resist pattern, and forming a second uneven shape on the surface of the area of the base film where the first uneven shape is formed, which is not covered with the resist pattern. And removing the resist pattern on the base film.

In one embodiment, the step of forming the irregularities on the base film includes the step of forming the first irregularities on the base film and the area of the base film where the first irregularities are formed. And forming a second uneven shape by selectively forming an insulating film.

In one embodiment, the step of forming the unevenness on the base film includes the step of forming the base film on the substrate with a different material for each predetermined surface area, and the step of forming the different unevenness on each material. Performing the steps.

In one embodiment, the step of forming an uneven shape on the base film is selectively performed for each picture element.

In one embodiment, the size of the concavo-convex shape is made different for each picture element.

In one embodiment, the step of forming irregularities on the underlayer is selectively performed on a plurality of portions in one picture element.

In one embodiment, the size of the concavo-convex shape is made different at a plurality of portions within one picture element. In one embodiment, the film comprises an organic polymer.

In one embodiment, a material mainly composed of polyimide, polyamide, polystyrene, polyamide imide, epoxy acrylate, spirane acrylate, or polyurethane is used as the organic polymer film. Ah
In one embodiment, an alkyl group is used as the organic polymer film.
A material containing polyimide as a main component is used. A certain fruit
In an embodiment, the organic polymer film has an alkyl group.

[0044]

According to the method of manufacturing a liquid crystal display device of the present invention, the alignment characteristics of the alignment film can be varied for each fine region by various methods as described below.

First, a method for imparting alignment characteristics to a film that becomes an alignment film by light irradiation (hereinafter referred to as an alignment film material) will be described. The principle is as follows.

When high energy is applied to the alignment film material by light irradiation, a change occurs in the structure of the polymer forming the alignment film material. As a result, for example, a component that has developed a large pretilt angle changes and the pretilt angle decreases, or conversely, a chemical reaction occurs to increase the pretilt angle. When regions having different pretilt angles are formed in the same substrate and a region having a large pretilt angle and a region having a small pretilt angle are combined between a pair of substrates, the alignment state is regulated on the side having a large pretilt angle. By utilizing this phenomenon, it is possible to form an orientation in an arbitrary direction in an arbitrary region.

Here, the selective light irradiation for each location on the alignment film material can be performed by inserting a mask (for example, a patterning substrate) between the light source and the substrate. In addition, a resist can be applied and patterned to distinguish a light-irradiated region from a non-irradiated region. By irradiating light to the alignment film material through these masks, light is irradiated only to a predetermined portion of the alignment film material according to the pattern of the mask. The alignment film to which the alignment characteristics are imparted varies from region to region depending on the presence or absence of light irradiation.

Also, by condensing the light to a size smaller than the desired area, it is possible to irradiate the light only to the desired area without using a means for blocking the light. A lens may be used to collect the light, or a laser beam may be used. According to this method as well, different alignment states can be formed for each range having a small area, similarly to the above method. Irradiation can be performed through a mask using a laser beam having a large area irradiation ability, so that the processing ability can be improved.

The region where the light irradiation is performed may be formed for each picture element, or may be formed for each of a plurality of divided areas within one picture element. The strength may be changed. More precise images can be obtained by light irradiation of various patterns. As the light to be irradiated, ultraviolet light, visible light, infrared light, or the like can be used as long as the alignment film can be given energy of a certain level or more. In addition, since the alignment film material only needs to have a component that changes with energy in its structure, resins such as polyamide, polyamide, polystyrene, polyamideimide, epoxy acrylate, and polyurethane can be used in addition to polyimide resin.

According to another alignment control method of the present invention, a film to be an alignment film is subjected to a first surface treatment for defining an alignment direction, and a second surface treatment is performed on the alignment film having been subjected to the first surface treatment. The above-mentioned operations for determining the pretilt angle (such as imparting a chemical change on the surface of the alignment film by light irradiation, forming irregularities on the surface of the alignment film by light irradiation, etc.) are performed.

Here, as a method for forming irregularities on the surface of the alignment film in order to control the pretilt angle, there is the following method other than light irradiation. That is, before forming a film to be an alignment film, a method of forming unevenness on a transparent conductive film serving as a base thereof, transmitting the unevenness to an upper alignment film, and indirectly forming unevenness on the surface of the alignment film. It is.

To locally change the shape and degree of the irregularities on the transparent conductive film, an insulating film or a resist is provided on a part of the transparent conductive film, and the surface of the transparent conductive film in this state is irradiated with light. Irregularities are formed on the surface of the transparent conductive film that has been irradiated with light by the same principle as described above. Since the portion where the resist and the insulating film are formed has not been irradiated with light, the surface thereof has a smaller degree of unevenness than the irradiated portion. Therefore, the surface state differs between the portion where the resist or the insulating film is applied and the portion where the resist or the insulating film is not applied.

Even before the light irradiation is performed, the insulating film is covered with the alignment film while the insulating film is left on the transparent conductive film originally having a rough surface, and the insulating film forming portion and the portion where the insulating film is not formed are formed. The difference in the surface state is considered in consideration of the height difference between the two.

According to this method, it is also possible to form an alignment state in which the pretilt angle differs for each minute area.

As described above, by changing the alignment state of the liquid crystal in the same liquid crystal cell into at least two kinds, the change in the refractive index in the normal viewing angle direction is reduced, and not only the viewing angle is widened, but also the opposite viewing angle characteristic is improved. Is done.

The alignment control method of the present invention can also be used for a scattering mode liquid crystal display device. Light incident on a liquid crystal display device in which a plurality of minute discontinuous alignment regions are formed in the same liquid crystal cell by the method of the present invention is scattered by a large number of minute regions having different alignment characteristics from each other (in the liquid crystal cell). When no voltage is applied). However, when a predetermined voltage is applied between opposing substrates (in a liquid crystal cell), liquid crystal molecules can be uniformly aligned. In this manner, light can be switched by scattering / non-scattering of light according to a change in alignment uniformity due to non-application / non-application of voltage to the liquid crystal cell.

[0057]

Embodiments of the present invention will be described below.

Embodiment 1 FIG. 1 schematically shows a light irradiation step in a method for manufacturing a liquid crystal display device according to the present invention. Pixel portions 12, 13, and 14 are formed on a substrate 16, and the alignment film 10 covers the pixel portions 12, 13, and 14.
Are formed. At a position facing the surface of the substrate 16, a mask 11 for a light irradiation step described later is arranged.
As a specific structure of the substrate 16 on which the picture elements 12, 13, and 14 are formed, a segment structure, a dot matrix structure, or the like can be applied. Further, the present invention is applicable to all substrate structures conventionally used in liquid crystal display devices.

According to the first embodiment, first, the picture element portions 12, 13, and 14 are formed on the substrate 16 by a known method. Next, the substrate 1 is covered with the picture element portions 12, 13 and 14.
6 An alignment film 10 is formed on the entire surface. In the first embodiment, a polyimide (PI) film, which is one of organic polymer films, is used as the alignment film 10. Since the polyimide-based polymer has a polymer chain and the long chain direction of the polymer chain on the surface of the polyimide film is oriented in the rubbing direction by a rubbing process performed later, the liquid crystal contacting the alignment film 10 made of the polyimide film Is considered to be oriented in the rubbing direction.

After forming the alignment film 10, the alignment film 10 is irradiated with light 15. The irradiation step of the light 15 may be performed at any time after the formation of the alignment film 10. More specifically, it may be at any time after the application of the alignment film 10, after the preliminary baking, after the rubbing, and after the cleaning of the substrate 16 after the rubbing. After the opposing substrate (not shown) is bonded to the substrate 16, the light may be irradiated through the opposing substrate. Must be used.

The pretilt angle of the liquid crystal layer in contact with the alignment film 10 due to light irradiation changes according to the following principle.

By irradiating the alignment film 10 with light 15 and applying energy, the chemical structure of the alignment film 10 changes. More specifically, when the polyimide alignment film 10 is irradiated with UV light, O ₃ (ozone) is generated, and the O ₃ oxidizes the alkyl group of the polyimide to a carbonyl group. It is considered that this changes the polarity of the surface of the alignment film 10, and thus changes the pretilt angle of the liquid crystal molecules, which are polar molecules. The alignment film 10 is irradiated with light.
It is also considered that the pretilt angle changes when the surface tension of the surface changes.

The relationship between the light irradiation on the alignment film and the change in the pretilt angle has been experimentally confirmed. FIG. 2 is a graph showing the light irradiation dependence of the pretilt angle of the liquid crystal molecules on the surface of the alignment film when a certain polyimide film is used as the alignment film and light is irradiated. As can be seen from the figure, the longer the light irradiation time, that is, the larger the light irradiation amount, the smaller the pretilt angle.

Further, as another mechanism, it has been experimentally confirmed that the degree of unevenness on the surface of the alignment film changes by irradiating the alignment film with light and applying energy. It has been experimentally confirmed that the pretilt angle changes when the degree of the unevenness of the alignment film surface changes. This is shown below.

As one method for indicating the state of unevenness on the surface of the film,
The average roughness shown in FIG. 3 is defined. The solid line curve in the figure indicates the actual surface of the alignment film, and the dashed line indicates the center plane of the irregularities on the actual surface. The center plane is defined as a plane parallel to a plane that satisfies the following equation and minimizes the square of the difference from the real surface, where An is the area of each convex portion of the real surface (n is a natural number) and Bn is the concave portion. You.

(A1 + A2 +... + An) = (B1 + B2 +... + Bn) The average roughness of the film surface is defined by the arithmetic average of the absolute value of the difference between the central plane and the real plane. FIG. 4 is a graph in which the average roughness is plotted on the horizontal axis and the pretilt angle is plotted on the vertical axis. In Example 1, a polyimide film was used as the material of the alignment film. However, as can be understood from the drawing, it can be seen that the pretilt angle decreases linearly as the average roughness of the surface of the alignment film increases. . By controlling the amount of light irradiation in this way,
Therefore, the pretilt angle of the liquid crystal can be arbitrarily controlled in the range of 0 ° to about 15 ° by controlling the unevenness of the alignment film surface. That is, various liquid crystal display devices having different pretilt angles can be manufactured. In this case, as described below, light irradiation can be selectively performed in place.

When light is irradiated using the mask 11 as shown in FIG. 1, a portion 11a indicated by oblique lines is a light-shielding portion that does not substantially transmit the light 15. Portions 11 b of the mask 11 that are not shaded are transmission portions that substantially transmit the light 15. As the mask 11, for example, a mask similar to a photomask usually used in photolithography technology can be used. A mask pattern may be directly formed on the alignment film 10 using the photolithography technique, and the mask may be peeled off after irradiation with light. However, when resist patterning is used, the degree of contamination of the alignment film 10 is large.

It is not necessary for the light shielding portion to completely block the light 15. It suffices if there is a difference in the degree of blocking between the light shielding part and the non-light shielding part. For example, a material having two or more types of regions having different light transmittances on the substrate 16 may be provided as the mask 11. In this case, two or more types of regions having different orientations can be formed in the same liquid crystal cell.

FIG. 5 shows that the pretilt angle of the liquid crystal in the region irradiated with light is different from the pretilt angle of the liquid crystal in the region not irradiated with light. The pretilt angle of the liquid crystal becomes α ゜ in the picture element portions 12 and 14 to which the light has not been irradiated, and the pretilt angle becomes β ゜ different from α ゜ in the picture element portion 13 to which the light has been irradiated. FIG. 6 shows a pair of substrates 1 to which the alignment control method of the first embodiment is applied.
9 schematically illustrates a cross section of a main part of a liquid crystal display device including 7 and 18. As shown in FIG. 6, the pretilt angles of the liquid crystal are different in regions A, A ′, B, and B ′ in the same liquid crystal cell.

As a method of selectively irradiating light at a location, a predetermined area may be selectively irradiated with light using condensed light. Although any of ultraviolet light, visible light, infrared light, or a combination thereof may be used as light for irradiating the alignment film 10 made of a polyimide film, high energy for changing the alignment state can be easily obtained. As the light source, ultraviolet light having a wavelength of 400 nm or less is preferable. Irradiation of light of such a wavelength is easily performed by using, for example, a high-pressure mercury lamp. When irradiating with ultraviolet light (UV light), 1000 (mJ / cm ² ) to 10,000 (mJ /
Irradiation is preferably performed under the condition of cm ² ).

In addition to ultraviolet light, laser light having a wavelength of visible light, infrared light, or a combination thereof may be used. In this case, the efficiency is high because the energy of the laser is added in addition to the energy of the wavelength of light.

Instead of light irradiation, it is also possible to locally change the alignment characteristics of the alignment film 10 by irradiation with another energy beam. For example, the chemical structure of the alignment film 10 can be locally changed by irradiation with an electron beam, an ion beam, X-rays, or the like.

Since fine processing using a mask or condensed light can be performed up to several microns, fine regions having different alignment characteristics are formed in the alignment film 10 in an arbitrary plane shape using such a method. be able to. For example, in the first embodiment, light is selectively radiated for each unit pixel by the mask 11, but a region to which the light 15 is not radiated and a region to be radiated may be formed in the unit pixel. Further, instead of making a difference only between light irradiation and non-irradiation, the light intensity between irradiation parts may be made different. In addition, all areas are irradiated with light,
The intensity of the irradiated light may be changed for each predetermined area (for example, for each of the above-described unit picture elements). With various light irradiation patterns, the orientation characteristics can be changed more minutely and locally.

Although a polyimide film is used as the alignment film 10 in this embodiment, an alignment film 10 made of another material may be used. An appropriate wavelength of light to be irradiated is selected according to the type of the material.

In addition, an inorganic alignment film containing silicon nitride, silicon oxide, fukkamagnesium or gold as a main component may be used. In this case, a high energy light such as an ultraviolet laser or an electron beam is used. Irradiation is required.

(Embodiment 2) In Embodiment 2, a method is employed in which the pretilt angle is controlled by forming irregularities on the surface of the alignment film in the same manner as the above-described light irradiation. The substrate structure is the same as in the first embodiment. In Example 2, polyimide was used as a material for the alignment film, and the alignment film was formed by spin coating or printing. As a material for the alignment film, an organic film such as polyamide, polystyrene, polyamideimide, epoxy acrylate, spirane acrylate, or polyurethane can be used. After firing the alignment film, rubbing was performed with a polishing cloth.

Thereafter, the surface of the alignment film was brought into contact with an alkaline solution, and irregularities of an arbitrary size were formed on the surface of the alignment film by utilizing the non-uniformity of the dissolving action of the solution on the alignment film. 0.5% NaOH aqueous solution or 2.
A 38% TMAH aqueous solution or the like can be used.

As a fluid to be brought into contact with the alignment film in order to form irregularities on the surface, hydrofluoric acid, nitric acid or an acid solution containing both as main components may be used. Ozone or ammonia gas, which is a reactive gas, may be used. A gas in a plasma state containing oxygen, argon, krypton, or the like as a main component may be used.

As in the case of the light irradiation in the first embodiment, the degree of the unevenness may be changed for each picture element, or may be changed for each of a plurality of divided areas in one picture element. With a simple pattern, a more precise image can be obtained.

(Embodiment 3) In Embodiment 3, another embodiment in which unevenness is formed on the surface of an alignment film will be described. In the third embodiment, arbitrary irregularities are formed on the surface of the transparent conductive film for applying a voltage to the liquid crystal, and the irregularities of the transparent conductive film are transmitted to the alignment film formed on the transparent conductive film. The method of forming unevenness is adopted. In this case, as a method of controlling the unevenness formed on the transparent conductive film, a method of contacting the transparent conductive film with an acid or alkali solution or a method of contacting a reactive gas or a gas in a plasma state or a method of energy after depositing the transparent conductive film. Control by changing the chemical structure of the surface of the transparent conductive film by irradiating high-wavelength light or laser and changing the chemical structure of the surface of the transparent conductive film by light energy (hereinafter referred to as surface treatment), and controlling by adjusting the film forming conditions of the transparent conductive film. (Hereinafter referred to as film formation condition control). In the latter film forming condition control method, for example, when a transparent conductive film is deposited by a sputtering method, the surface of the deposited transparent conductive film becomes flatter as the density of the sputter target increases and the deposition rate decreases. , Resulting in a film with less irregularities. These film forming condition control method and the former surface treatment method are used alone,
Or they can be used in combination. In the case of a surface treatment method in which unevenness is controlled by high-energy short-wavelength light or light energy from a laser or the like, unevenness can be selectively controlled by condensing light by a light condensing means in addition to a mask.

Next, a specific example of a method for forming irregularities on the surface of the alignment film will be described. FIG. 7 schematically shows a cross section of the substrate 50 on which the transparent conductive films 42 having different surface states are formed. The first transparent conductive film 42a is formed on the entire surface of the substrate 50.
Are laminated, and a second transparent conductive film 42b is formed on a part of the first transparent conductive film 42a. Such a substrate 50 is formed as follows.

First, a first transparent conductive film 42a having a flat surface is formed on a substrate 50 by a sputtering method or an evaporation method.
(Glass substrate). Thereafter, the second transparent conductive film 42b is formed only on a predetermined region of the first transparent conductive film 42a. First transparent conductive film 42a and second transparent conductive film 42
As b, an ITO (indium oxide) film is widely used. Although the ITO film is used in the third embodiment, a transparent conductive film made of another material may be used.

The second transparent conductive film 42b is replaced with the first transparent conductive film 4
There are a plurality of methods for forming only in the predetermined region 2a. For example, in a sputtering apparatus (or an evaporation apparatus), a metal mask 41 is interposed between a target (an evaporation source) and a substrate 50, and a film serving as a second transparent conductive film 42b is formed as a first transparent conductive film 42b.
There is a method of depositing on the transparent conductive film 42a. According to this method, the opening of the mask 41 corresponds to the predetermined area, whereby the second transparent conductive film 4 is formed only on the predetermined area.
2b will grow. At this time, for example, by increasing the deposition rate of the second transparent conductive film 42b as compared with the deposition rate of the first transparent conductive film 42a by the above-described film formation control method, the surface of the second transparent conductive film 42b is The degree of the unevenness can be made larger than the degree of the unevenness of the first transparent conductive film 42a.

The following lift-off method can be used. This will be described with reference to FIG. In the lift-off method, first, a resist pattern film (not shown) having an opening for exposing a predetermined region of the first transparent conductive film 42a is formed on the first transparent conductive film 42a. Such a resist pattern film is formed by a known photolithography technique using a photomask having a pattern corresponding to the pattern of the mask 41.

Next, a film to be the second transparent conductive film 42b is deposited on the entire surface of the resist pattern film and the first transparent conductive film 42a. Thereafter, by removing the resist pattern film, a portion existing on the resist pattern is removed, thereby forming the second transparent conductive film 42b only on a predetermined region of the first transparent conductive film 42a.

Next, these transparent conductive films 42a, 42b
And an alignment film (not shown) so as to cover a base film such as an insulating film.
Is formed, followed by a rubbing treatment. After the formation of the alignment film, the same steps as in the related art are employed.

According to the orientation control method of the third embodiment, the orientation of the liquid crystal can be changed for each of the picture element portions 43, 44 and 45 as schematically shown in FIG. This is because the surface of the base film (transparent conductive film) of the alignment film is flat (the part where the first transparent conductive film 42a is exposed), and
This is because there is a difference in the alignment characteristics of the liquid crystal between a portion having irregularities (a portion where the second transparent conductive film 42b exists). In the third embodiment, the base film (the transparent conductive film 42a,
Utilizing the fact that the pretilt angle of the liquid crystal can be changed according to the difference in the surface morphology 2b). The pretilt angle remains at α ゜ in the picture element portions 43 and 45 having a flat underlayer surface, and the pretilt angle changes to β 絵 in the picture element portion 44 having an uneven surface of the underlayer film. In the method of controlling the alignment characteristics of the alignment film using the base film as in the third embodiment, the base film may have any shape as long as the degree of unevenness on the surface of the base film can be locally changed. Can be done with a membrane. Alternatively, the surface of the lower layer of the transparent conductive film may be subjected to surface treatment, and consequently the unevenness of the alignment film may be controlled.

Also in this case, the degree of the unevenness is changed for each picture element and for each of a plurality of regions within one picture element as in the previous embodiment, so that the unevenness can be formed in various patterns. is there.

As described above, the pretilt angle of the liquid crystal can be easily locally changed in the same liquid crystal cell by the alignment control method of the third embodiment. By using this method, the viewing angle characteristics in the TN mode and the STN mode can be improved.

According to the method employed in the third embodiment, the resist pattern film is formed on the transparent conductive film 42a but not on the alignment film. Therefore, there is no concern that the alignment film is contaminated by the photolithography process for forming the resist pattern film.

Example 4 In Example 4, asperities are formed on a transparent conductive film which is a base film of an alignment film, and the unevenness is transmitted to an upper alignment film to form an unevenness on the surface of the alignment film. As a method of selectively forming unevenness on the transparent conductive film, a resist using conventional photolithography is patterned on a part of the transparent conductive film, and in this state, light is irradiated, and a location is determined depending on whether or not the light is irradiated. A method of forming a typical uneven change is adopted. FIG. 9 schematically shows a process of orientation control according to the fourth embodiment.

First, as shown in FIG.
A transparent conductive film 43 is formed thereon. Next, as shown in FIG. 9B, a resist 47 is formed on a part of the transparent conductive film 43.
To form In this state, as shown in FIG. 9C, light 15 is irradiated perpendicularly to the substrate 50 from the side where the transparent conductive film 43 is formed. Since the portion of the transparent conductive film 43 covered with the resist 47 is not irradiated with light, the surface state does not change from that at the time of forming the transparent conductive film 43 as shown in FIG. On the other hand, in the part that has been irradiated with light, the chemical structure of the surface changes, and irregularities occur.

After the light irradiation, the resist 47 is removed as shown in FIG.

Finally, as shown in FIG. 9E, the alignment film 10 is formed on the surface of the substrate 50 after removing the resist 47 so as to cover the transparent conductive film 43. The surface state of the transparent conductive film 43 is also reflected in the surface state of the alignment film 10 formed thereover between the portion where the transparent conductive film 43 has been irradiated with light and the portion where the light irradiation has not been performed. A portion that has been formed and a portion that has not been formed are formed.

In the fourth embodiment, an insulating film may be used instead of the resist. FIG. 10 shows a schematic process in the case where an insulating film is used. It is the same as the case where the above-mentioned resist is used except that the removing step in the case of the resist is eliminated. The alignment film is formed by covering the insulating film while leaving it on the transparent conductive film. In the region where the insulating film is formed, not only the difference between the surface states of the insulating film and the transparent conductive film, but also the surface of the insulating film. And the height difference between the transparent conductive film surface and the surface of the transparent conductive film are also taken into account in the unevenness element transmitted to the alignment film.

In the portion where the insulating film is formed, the uneven shape becomes gentle.

In the case where an insulating film is used, the removal step in the case where a resist is used is eliminated, so that the process is simplified. In addition, the manufacturing process is simplified in the sense that both the insulating treatment and the alignment control are performed, and a liquid crystal display device having low cost and highly reliable viewing angle characteristics can be provided.

Further, in order to form irregularities in the transparent conductive film region other than the resist or the insulating film formation region, a method of contacting the transparent conductive film with an acid or alkali solution or a method of contacting a reactive gas or a gas in a plasma state. May be used.

The formation area of the resist and the insulating film can be determined for each picture element as in the previous embodiment, or for each of a plurality of areas within one picture element, and irregularities can be formed in various patterns. It is.

(Example 5) In Example 5, as in Examples 3 and 4, irregularities were formed on the base film of the alignment film, and the irregularities were transmitted to the upper alignment film to form a surface on the alignment film. The method of forming unevenness is adopted, but the unevenness forms an insulating film on the transparent conductive film, and due to the difference in the material of the transparent conductive film and the insulating film,
The different irregular shapes on each surface are transmitted to the alignment film.

The alignment control process according to the fifth embodiment is shown in FIG.
Is shown schematically in FIG.

First, as shown in FIG.
Then, a transparent conductive film 43 is formed on “0”. Next, FIG.
As shown in (b), an insulating film 46 is formed on a part of the surface of the transparent conductive film 43. As the insulating film 46, silicon nitride, silicon oxide, or the like can be used.

Finally, as shown in FIG. 11C, the alignment film 10 is formed on the surface of the substrate 50 so as to cover the transparent conductive film 43 and the insulating film 46.

In the region where the insulating film is formed, not only the difference between the surface states of the insulating film and the transparent conductive film but also the height difference between the insulating film surface and the transparent conductive film surface is transmitted to the alignment film. It is added. In the portion where the insulating film is formed, the uneven shape becomes gentle.

In the fifth embodiment, before forming the insulating film,
A liquid crystal display device having a very simple manufacturing process, low cost and highly reliable viewing angle characteristics, because it performs both insulation treatment and alignment control without performing light irradiation or other operations for forming unevenness. Can be provided.

Also in the fifth embodiment, the formation region of the insulating film is determined for each picture element as in the previous embodiment, for each of a plurality of areas within one picture element, or in various patterns. Irregularities can be formed.

(Embodiment 6) In Embodiment 6, a base film is formed of a different material for each predetermined region. In this method, the unevenness of the underlying film is obtained by utilizing the unevenness of the surface treatment due to the difference in the material of the underlying film of the alignment film, so that the combination of films of arbitrary materials is used as in the previous embodiment. It is possible to form unevenness in various patterns, such as a change in each element or a change in each of a plurality of regions within one picture element.

By using such various alignment control methods of the present embodiment, it is easy to form regions having different alignment states in the same liquid crystal cell and thus different viewing angle characteristics in an arbitrary pattern. . By forming these different viewing angle characteristics, the viewing angle in the TN mode or the STN mode can be improved. For example, in the case where a TN mode liquid crystal display device is arranged between a pair of polarizing plates, in order to improve the viewing angle characteristic of a liquid crystal display reversal phenomenon, the vertical direction of the liquid crystal molecules (perpendicular to the observer). Is considered to be constant regardless of the viewing angle. That is, when viewed from the normal viewing angle direction, the anisotropy (Δn) of the refractive index in the vertical direction becomes “large” as the viewing angle increases from right above the liquid crystal display device (in the direction perpendicular to the substrate surface). → "0" →
What is necessary is just to suppress the change to “large (reverse direction)”. According to the present invention, the anisotropy of the refractive index of the liquid crystal molecules is suppressed.
The change in n can be reduced.

A liquid crystal display device employing an alignment film for aligning liquid crystal molecules in a certain direction has a problem in viewing angle characteristics.
By using the method for manufacturing a liquid crystal display device according to the present invention, liquid crystal molecules can form different alignment states for each minute range, thereby improving viewing angle characteristics. Further, according to the present invention, the phenomenon of reversal in the normal viewing angle direction, which has been particularly concerned in the past, is also improved.

The manufacturing method according to the present invention can also be applied to a scattering mode liquid crystal display device. According to the method of manufacturing a liquid crystal display device according to the present invention, since several different alignment states are provided in the same liquid crystal cell for each minute range, when no voltage is applied to the liquid crystal layer, light passing through the liquid crystal layer is scattered. . This is because the orientation angle of the liquid crystal molecules differs for each minute range. However, when a voltage is gradually applied to the liquid crystal layer, the liquid crystal molecules rise, so that light passes through the liquid crystal layer. That is, the optical switching operation can be performed according to the application / non-application of the voltage to the liquid crystal.

[0111]

As described above, according to the method of manufacturing a liquid crystal display device according to the present invention, the pretilt angle of liquid crystal molecules can be easily controlled. Since different alignment states can be formed by changing the pretilt angle for each minute range, the viewing angle of a TN mode or STN mode liquid crystal display device can be improved without increasing the cost. According to this method, a change in the refractive index of the liquid crystal in the thickness direction of the liquid crystal cell in the conventional liquid crystal display element can be reduced. As a result, the reversal phenomenon of the normal viewing angle direction (the phenomenon that the black and white (negative / positive) of the image is reversed at a specific viewing angle) can be improved.

The liquid crystal display device according to the present invention, which is manufactured under such an orientation control by the tilt angle control, is a display device capable of providing a high-contrast, high-quality display.

The present invention can be applied to the optical switching mode and can be performed by a simple process.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing an alignment control method according to the present invention.

FIG. 2 is a view showing the light irradiation dependency of a pretilt angle.

FIG. 3 is a diagram showing a definition of average roughness.

FIG. 4 is a diagram showing the average roughness dependency of a pretilt angle.

FIG. 5 is a cross-sectional view showing a state in which the pretilt angle changes for each picture element portion by the light irradiation shown in FIG.

FIG. 6 is a cross-sectional view schematically showing a liquid crystal layer between substrates whose orientation is controlled by the method of the present invention.

FIG. 7 is a cross-sectional view schematically showing another alignment control method according to the present invention.

FIG. 8 is a cross-sectional view showing a state in which the pretilt angle changes for each picture element portion by the method of FIG.

FIG. 9 is a diagram showing a fourth embodiment according to the present invention.

FIG. 10 is a diagram showing a fifth embodiment according to the present invention.

FIG. 11 is a diagram showing a fifth embodiment according to the present invention.

FIG. 12 is a graph showing an applied voltage-transmittance characteristic in a liquid crystal display device.

FIG. 13 is a perspective view for explaining viewing angle characteristics in a liquid crystal display device.

FIG. 14 is a cross-sectional view for explaining viewing angle characteristics in a liquid crystal display device.

FIGS. 15 (a), (b) and (c) are diagrams for explaining an inversion phenomenon in a liquid crystal display device.

[Explanation of symbols]

 10, 31c, 32c Alignment film 11, 41 Mask 11a Shielding part 11b Transmission part 12, 13, 14 Picture element part 15 Light 16, 17, 18, 50 Substrate 31, 32 Opposite substrate 33, 34 Rubbing direction 31a of liquid crystal display element , 32a Glass substrate 31b, 32b Transparent electrode 35 Central molecule 36 Viewing direction 37 Observer 42, 43 Transparent conductive film 46 Insulating film 47 Resist

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Noriko Watanabe 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (56) References JP-A-2-55330 (JP, A) JP-A-1- 277819 (JP, A) JP-A-1-238619 (JP, A) JP-A-3-168721 (JP, A) JP-A-59-87428 (JP, A) JP-A-3-123318 (JP, A) JP-A-1-120531 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02F 1/1337

Claims (32)

(57) [Claims] 1. A method for manufacturing a liquid crystal display device in which a liquid crystal layer is sandwiched between a pair of substrates and picture elements are arranged in a matrix, wherein the orientation of the liquid crystal layer is controlled by at least one of the pair of substrates. forming a film to be the alignment film which controls the pretilt angle of the liquid crystal molecules by irradiating light to the membrane, and includes a step of imparting orientation properties to the membrane, in the substrate Forming regions with different pretilt angles, a pair of
A region with a large pretilt angle and a region with a small pretilt angle
By combining them, the alignment state can be changed
A method for manufacturing a liquid crystal display device formed in a direction . 2. The film is irradiated with the light by selectively defining a region with respect to a desired region of the film, and a pre-tilt angle between a light irradiation region and a non-light irradiation region is set to be different. The method for manufacturing a liquid crystal display device according to claim 1, wherein the alignment characteristics are imparted by rubbing. 3. The method according to claim 2, wherein the light irradiation area or the non-light irradiation area is formed using the picture element as a unit. 4. The light irradiation area is formed by irradiating light with different light intensities between picture elements.
3. The method for manufacturing a liquid crystal display device according to item 1. 5. The method for manufacturing a liquid crystal display device according to claim 1, wherein the light is irradiated such that the light irradiation part and the non-light irradiation part are mixed in one picture element. 6. The method of manufacturing a liquid crystal display device according to claim 1, wherein the light irradiating section is irradiated with light so that the light irradiating section in one picture element has a different light intensity. 7. The method according to claim 1, further comprising: forming a film to be an alignment film on both of the pair of substrates; and irradiating at least one of the films with light to control a pretilt angle of the film. 7. The method for manufacturing a liquid crystal display device according to any one of 2 to 6. 8. A method for manufacturing a liquid crystal display device according to claim 2, wherein a mask or a means for condensing light is used when selectively irradiating said film with said light. . 9. The method according to claim 1, wherein said film is made of an organic polymer. 10. The organic polymer film, wherein the organic polymer film is polyimide,
The method for manufacturing a liquid crystal display device according to claim 9, wherein a material containing polyamide, polystyrene, polyamideimide, epoxy acrylate, spirane acrylate, or polyurethane as a main component is used. 11. The method for manufacturing a liquid crystal display device according to claim 1, wherein said film is formed of one of an inorganic oxide film, an inorganic nitride film, an inorganic fluoride film and a metal film. . 12. The liquid crystal according to claim 1, wherein the light is selected from ultraviolet light, visible light, infrared light, and laser light having a wavelength corresponding to the light. A method for manufacturing a display device. 13. The method according to claim 10, wherein the light is one of ultraviolet light and laser light of this wavelength. 14. A method of manufacturing a liquid crystal display device in which a liquid crystal layer is sandwiched between a pair of substrates and picture elements are arranged in a matrix, wherein at least one of the pair of substrates controls alignment of the liquid crystal layer. Forming a film to be a film, performing a first surface treatment on the film to give an orientation direction of the liquid crystal layer, and providing unevenness for determining a pretilt angle of the liquid crystal layer on a part of the film. Performing a second surface treatment to form regions having different pretilt angles in the substrate;
A region with a large pretilt angle and a region with a small pretilt angle
By combining them, the alignment state can be changed
A method for manufacturing a liquid crystal display device formed in a direction . 15. The method according to claim 14, wherein the second surface treatment is selectively performed in units of one picture element. 16. The method for manufacturing a liquid crystal display device according to claim 14, wherein the second surface treatment is performed so that the size of the unevenness differs between picture elements. 17. The method according to claim 14, wherein the second surface treatment is selectively performed on a plurality of portions in one picture element. 18. The method according to claim 14, wherein the second surface treatment is performed such that the size of the unevenness is different in a plurality of portions in the picture element.
3. The method for manufacturing a liquid crystal display device according to item 1. 19. The liquid crystal display device according to claim 14, wherein the second surface treatment is performed by bringing a solution containing either an acid or an alkali as a main component into contact with the surface of the film. Manufacturing method. 20. The method of manufacturing a liquid crystal display device according to claim 14, wherein the second surface treatment is performed by bringing one of a reactive gas and a gas in a plasma state into contact with the surface of the film. Method. 21. A method for manufacturing a liquid crystal display device in which a liquid crystal layer is sandwiched between a pair of substrates and picture elements are arranged in a matrix, comprising: forming a base film on at least one of the pair of substrates; A step of forming an uneven shape on the base film; forming a film that covers the base film as an alignment film for controlling the alignment of the liquid crystal layer; transmitting the uneven shape to the film to pretilt the liquid crystal layer; a step of imparting the unevenness to determine the corners membrane, include the step of applying the alignment direction of the liquid crystal layer to the membrane, the step of forming an uneven shape on the lower ground layer, a plurality of in one picture element
The pre-tilt angle differs by selectively applying
A large pretilt angle between the pair of substrates.
By combining the area and the small area,
A method for manufacturing a liquid crystal display device, wherein a state is formed in an arbitrary direction in an arbitrary region . 22. A step of forming a concave-convex shape on the base film, the step of forming a first concave-convex shape on the base film; Forming a resist pattern on the surface of the base film, and forming a second resist pattern on a surface of the base film not covered with the resist pattern in the region where the first unevenness is formed.
22. The method for manufacturing a liquid crystal display device according to claim 21, comprising the steps of: forming a concave-convex shape; and removing the resist pattern on the base film. 23. The step of forming a concave-convex shape on the base film, the step of forming a first concave-convex shape on the base film, and the step of forming a first concave-convex shape on the base film in the region where the first concave-convex shape is formed. 22. The method for manufacturing a liquid crystal display device according to claim 21, further comprising a step of selectively forming an insulating film and causing a second uneven shape on the insulating film. 24. The step of forming the irregularities on the underlayer film comprises the steps of: forming the underlayer film on the substrate with a different material for each predetermined surface area; and forming a different irregularities for each material. 22. The method for manufacturing a liquid crystal display device according to claim 21, comprising: 25. The method for manufacturing a liquid crystal display device according to claim 21, wherein the step of forming the irregularities on the base film is selectively performed for each picture element. 26. The method of manufacturing a liquid crystal display device according to claim 21, wherein the size of the uneven shape is made different for each picture element. 27. The method for manufacturing a liquid crystal display device according to claim 21, wherein the step of forming the uneven shape on the base film is selectively performed at a plurality of portions within one picture element. 28. The method for manufacturing a liquid crystal display device according to claim 21, wherein the size of the uneven shape is made different at a plurality of portions within one picture element. 29. The film according to claim 21, wherein said film is made of an organic polymer.
29. The method for manufacturing a liquid crystal display device according to any one of items 28 to 28. 30. The organic polymer film, comprising polyimide,
30. The method for manufacturing a liquid crystal display device according to claim 29, wherein a material mainly containing polyamide, polystyrene, polyamideimide, epoxy acrylate, spirane acrylate, or polyurethane is used. 31. An alkyl group as the organic polymer film.
10. A material having a polyimide as a main component.
3. The method for manufacturing a liquid crystal display device according to item 1. 32. The organic polymer film has an alkyl group.
A method for manufacturing a liquid crystal display device according to claim 10.