JP2000314889A - Liquid crystal display element and surface treatment method and apparatus for alignment film - Google Patents

Abstract

(57) [Problem] To provide a liquid crystal display element capable of realizing a wide viewing angle and a surface treatment method and apparatus of an alignment film. SOLUTION: A pair of substrates 110 and 120 having a closed space into which a liquid crystal is injected, and substrates facing each other in the closed space.
Electrodes 130 and 140 formed on inner surfaces of the electrodes 110 and 120, a first alignment film 150 formed on one inner surface on which the electrodes 130 and 140 are formed to align liquid crystal in at least one direction, , 140, a second alignment film 160 formed on the inner surface of the other side to align the liquid crystal in an arbitrary direction, and a liquid crystal layer 170 filled in the closed space. The liquid crystal molecules are substantially vertically aligned in the first alignment film, and the liquid crystal molecules are substantially horizontally aligned in the second alignment film. At this time, the liquid crystal layer is filled with a liquid crystal having a positive or negative dielectric anisotropy. When the liquid crystal layer is filled with a liquid crystal having a positive dielectric anisotropy, biaxial compensation for compensating a viewing angle is provided on the front surface of the substrate. the film
It is desirable to further comprise 250.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a liquid crystal display element capable of realizing a wide viewing angle and a method and an apparatus for surface treatment of an alignment film.

[0002]

2. Description of the Related Art In general, a liquid crystal display device has a twisted nematic (TN) type liquid crystal display device and a super twisted nematic (STN) type depending on the degree of twisting of a liquid crystal filled between two transparent substrates. They are roughly divided into liquid crystal display elements.

Referring to FIG. 9, a conventional TN type liquid crystal display device has a liquid crystal cell 1 for displaying an image by applying an electric field, and a polarizing plate 11 and an analyzing plate provided on the back and front of the liquid crystal cell 1, respectively. 12 are included.

The liquid crystal cell 1 is interconnected to form a back plate 2 and a front plate 3 forming a closed space filled with liquid crystal;
The common electrode 4 and the pixel electrode 5 having a predetermined pattern formed on the opposing surfaces of the back plate 2 and the front plate 3, respectively, and the liquid crystal molecules near the surface on the common electrode 4 and the pixel electrode 5 in a certain direction. Includes an alignment film 6 formed for alignment and a TN type liquid crystal 7 filled therebetween.

In the conventional TN type liquid crystal display device having the above-mentioned structure, when no voltage is applied, the T
The N-type liquid crystal 7 has a liquid crystal molecular arrangement twisted by about 90 °, and the molecular arrangement is changed by applying an electric field. Therefore, an image is displayed using the change in the brightness of the light passing through the analyzer 12 due to the change in the polarization state of the light passing through the TN type liquid crystal layer 7 due to the application of the electric field.

However, in such a TN-type liquid crystal display device, the TN-type liquid crystal 7 is aligned in a predetermined direction on the alignment film 6, and the liquid crystal molecule alignment is about 90 ° when the voltage is turned off.
Since the liquid crystal molecules are twisted and the liquid crystal molecules are arranged in parallel when the voltage is turned on, there is a problem that the brightness of the screen is significantly changed according to the direction in which the screen is viewed, and the viewing angle, particularly the vertical viewing angle, is narrow.

Further, the TN type liquid crystal display element has a problem that the contrast is remarkably changed depending on the viewing direction of the screen.

[0008]

SUMMARY OF THE INVENTION The present invention has been devised to solve the above-mentioned problems, and realizes a wide viewing angle by changing the orientation of liquid crystal molecules, thereby improving the angle dependence of contrast. To provide an improved liquid crystal display element.
There is a purpose.

A second object of the present invention is to provide a surface treatment method and apparatus for an alignment film for radially aligning liquid crystal molecules so as to achieve a wide viewing angle and improve the angle dependence of contrast. is there.

[0010]

In order to achieve the first object, a liquid crystal display according to the present invention comprises: a pair of substrates having a closed space into which liquid crystal is injected; An electrode formed on the inner surface of the first electrode, a first alignment film formed on one inner surface on which the electrode is formed to align the liquid crystal in at least one direction, and formed on the other inner surface on which the electrode is formed. It comprises a second alignment film for aligning liquid crystal in an arbitrary direction, and a liquid crystal layer filled in the closed space.

In the present invention, the liquid crystal molecules in the first alignment film are preferably aligned substantially vertically, and the liquid crystal molecules in the second alignment film are preferably aligned substantially horizontally, and the liquid crystal layer has a dielectric anisotropy. It can be composed of a liquid crystal that is negative or a liquid crystal that has a positive dielectric anisotropy.

Here, as described above, when the liquid crystal layer is made of liquid crystal having a positive dielectric anisotropy, it is preferable to further include a biaxial compensation film for compensating a viewing angle on the front surface of the substrate. .

According to a second aspect of the present invention, there is provided a method for treating the surface of an alignment film according to the present invention, comprising the steps of: preparing a substrate on which an alignment film made of a photo-alignable polymer is formed; Positioning a mask having a light transmitting region pattern, and irradiating the alignment film with light that is radially polarized in units of the light transmitting region from the light adjusting unit through the mask. .

According to a feature of the present invention, the light adjusting means corresponds to a rotating member having a light transmitting slit formed in a radial direction thereof, a light source unit for irradiating the rotating member with light, and a light transmitting slit. And a polarizer disposed between the light source unit and the alignment film so that light emitted from the light source unit and polarized by the polarizer is applied to the alignment film by rotation of the rotating member. It is provided so that it is radiated radially in units of light transmission areas.

Preferably, the polarizer is provided integrally with the rotating member.

It is preferable that the mask has a light transmitting region of substantially the size of a pixel so that light is radiated to the alignment film in a pixel unit.

According to the present invention, there is provided a surface treatment apparatus for an alignment film according to the present invention, comprising: a light source; a rotating member having a slit formed in a radial direction thereof for passing light emitted from the light source; A polarizer disposed between the light source and an alignment film made of a photo-alignable polymer to correspond to the light transmission slit; and a plurality of light transmission regions disposed between the rotating member and the alignment film. A mask having: a light source that is irradiated from the light source by the rotation of the rotating member, and light that is polarized by the polarizer is radially irradiated on the alignment film in a unit corresponding to the light transmission region through the mask. It is characterized by the following.

[0018]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

Referring to FIG. 1, a liquid crystal display according to a first embodiment of the present invention includes first and second substrates 110 and 120 having a closed space into which liquid crystal is injected, and the closed space. Electrodes 130 and 140 formed on the inner surfaces of the substrates 110 and 120 to be opposed to each other, first and second alignment films 150 and 160 for aligning liquid crystal, and the first and second substrates 110 and 120, respectively. 1
The liquid crystal cell 100 includes a liquid crystal layer 170 filled in 20 closed spaces.

The substrates 110 and 120 are interconnected to form a closed space. The first and second electrodes 130 and 140 are formed on a first electrode 130 formed on an inner surface of the first substrate 110.
A second electrode 140 is formed on the inner surface of the second electrode 120 so as to face the first electrode 130.

The first alignment film 150 is formed on one inner surface of the first substrate 110 on which the first electrode 130 is formed, and is subjected to an alignment process so that the liquid crystal is aligned in at least one direction. Further, as shown in FIG. 2A, the first alignment film 150
Pretilt angle of liquid crystal molecules near the alignment film 150 (pretilt angle)
Is 70 ° to 90 ° and / or -90 ° to -70 °
An alignment process is performed so that the substrate is substantially vertically aligned.

The second alignment film 160 is formed on the other inner surface of the second substrate 120 on which the second electrode 140 is formed, so that the liquid crystal can be randomly aligned in the vicinity of the film as a whole. It is desirable to be provided. Specifically, the second alignment film 160 is provided so that, when viewed in pixel units, the liquid crystal is randomly aligned or radially aligned in each pixel as shown in FIG. 2B.

Here, the random alignment in pixel units is performed by the non-polishing alignment of the liquid crystal by the second alignment film 160. In addition, the radial alignment of each pixel is performed using light, in particular, ultraviolet (UV) light, by a method and apparatus for treating the second alignment film 160, which will be described later.

In this case, it is preferable that the second alignment film 160 is provided near the second alignment film 160 so that the liquid crystal molecules can be substantially horizontally aligned at a tilt angle of about −25 ° to 25 °.

The liquid crystal layer 170 is made of liquid crystal having a negative dielectric anisotropy. In this case, any liquid crystal having a dielectric anisotropy of -60 to -1 can be used as the liquid crystal.

On the other hand, a surface light source device (not shown) is provided on the back surface of the liquid crystal cell 100, and light incident on the liquid crystal cell 100 from the surface light source device is provided between the surface light source device and the liquid crystal cell 100. A polarizing plate 180 for polarizing the liquid crystal, the liquid crystal cell 1
On the front surface of 00, an analyzer plate 190 for controlling the amount of light transmitted through the mixed liquid crystal cell 100 is provided. The liquid crystal cell 100 further includes a color filter (not shown) for displaying a color image. Although detailed illustration and description are omitted here, it is preferable that one of the first and second electrodes 130 and 140 be a common electrode, and the other be provided as a TFT array and a pixel electrode. In addition,
In the first embodiment, the polarizing plate 180 is provided on the upper surface of the first substrate 110, and the analyzer 190 is provided on the second substrate 120.
However, the present invention is not limited to this.

As described above, in the liquid crystal display device according to the first embodiment of the present invention, the first and second electrodes
When no driving voltage is applied to 130 and 140, that is, when the driving voltage is turned off, the liquid crystal molecules of the liquid crystal layer 170 are arranged as shown in FIG. When a driving voltage is applied to the first and second electrodes 130 and 140, the arrangement of the liquid crystal molecules is changed by the applied voltage. When the driving voltage is turned on, the liquid crystal molecules are arranged as shown in FIG. .

When the alignment of the liquid crystal molecules is changed by the application of the driving voltage, the liquid crystal molecules are emitted from the surface light source device due to the dielectric anisotropy, that is, the refractive index anisotropy, of the liquid crystal molecules. The light that has been substantially polarized by the above changes its polarization state while passing through the liquid crystal layer 170, so that the amount of light passing through the analyzer 190 changes. Therefore, the liquid crystal layer 17 according to the magnitude of the applied voltage
The change in the polarization of light at 0 indicates the luminance of the screen.

At this time, in the second alignment film 160 of the first embodiment according to the present invention, the liquid crystal molecules are oriented in an arbitrary direction, so that the liquid crystal molecules pass through the liquid crystal layer 170 when the above-described voltage is applied. The average phase delay value of the incident light is the viewing angle (viewing g
angle) regardless of the angle, the brightness of the screen according to the viewing direction of the screen hardly changes. Therefore,
The viewing angle, especially the vertical viewing angle, is widened, and the wide viewing angle (wid
e viewing angle) can be realized. Further, the angle dependency of the contrast according to the viewing angle of the screen is improved.

FIGS. 5 and 6 are cross-sectional views schematically showing a liquid crystal display device according to a second embodiment of the present invention. The same reference numerals as those in FIG. 1 denote the same parts. 1 shows a member that functions. Here, FIG. 5 is a cross-sectional view schematically showing a case where a voltage is not applied to the liquid crystal display element, and FIG. 6 is a cross-sectional view schematically showing a case where a voltage is applied to the liquid crystal display element. 5 and 6
Referring to, the liquid crystal display device includes a liquid crystal cell 200 and a compensation film 250 for compensating a viewing angle.

The liquid crystal cell 200 is provided in the same manner as the liquid crystal cell 100 of FIG. 1 except that the liquid crystal layer 270 is filled with positive liquid crystal having dielectric anisotropy. At this time, any liquid crystal having a dielectric anisotropy of 1 to 60 can be used as the liquid crystal.

As described above, when the dielectric anisotropy of the liquid crystal is positive, the phase difference of the light passing through the liquid crystal layer 270 changes according to the direction in which the screen is viewed, and the viewing angle can be narrowed.
In order to solve this, at least one compensation film 250 is provided on the front and / or back of the liquid crystal cell 200. The compensation film 250 is preferably provided on the front surface of the liquid crystal cell 200 so that the viewing angle characteristics can be further improved. At this time, the compensation film 250
Is preferably provided with a biaxial film so that not only the left and right viewing angles but also the up and down viewing angles are improved, and the two optical axes of the biaxial film are provided so as to be appropriately positioned.

In the liquid crystal display device according to the second embodiment of the present invention as described above, the arrangement of the liquid crystal molecules is determined when no driving voltage is applied to the first and second electrodes 130 and 140, that is, when the voltage is off. They are arranged as shown in FIG. When the driving voltage is applied, the arrangement of the liquid crystal molecules changes according to the magnitude of the applied voltage, and a larger driving voltage is applied. When the voltage is turned on, the liquid crystal molecules are arranged as shown in FIG.
When the arrangement of the liquid crystal molecules is changed by the voltage application, the light emitted from the surface light source device and polarized by the polarizing plate 180 changes its polarization state while passing through the liquid crystal layer 270. At this time, the amount of polarization change of the light passing through the liquid crystal layer 270 changes according to the magnitude of the applied voltage, and the amount of light passing through the analyzer 190 changes, indicating a change in screen brightness.

At this time, the liquid crystal molecules are entirely randomly aligned in the second alignment film 160 according to the second embodiment of the present invention.
The average phase delay value of light passing through 270 is the compensation film 2
Since it is compensated by 50 and becomes substantially constant irrespective of the viewing angle, the brightness of the screen according to the viewing direction of the screen hardly changes. Therefore, as in the first embodiment, the viewing angle, particularly, the vertical viewing angle is widened, and a wide viewing angle can be realized. In addition, the angle dependence of the contrast depending on the viewing angle of the screen is improved.

FIG. 7 is a perspective view schematically showing a liquid crystal display device according to a third embodiment of the present invention. Here, FIG.
The members having the same reference numerals have the same functions. Referring to FIG. 7, a liquid crystal display device according to a third embodiment of the present invention includes first and second substrates 110 and 120 having closed spaces into which liquid crystal is injected, and first and second substrates 110 and 120 forming the closed spaces. First and second electrodes 130 and 140 formed on the inner surfaces of the second substrates 110 and 120 to face each other, first and second alignment films 150 and 160 for aligning liquid crystal, and the first and second electrodes A liquid crystal layer 370 filled in a closed space between the two substrates 110 and 120;
The liquid crystal cell 300 includes a reflector 350 formed on the inner surface of the second substrate 120.

A polarizing plate 3 is provided on the front surface of the liquid crystal cell 300.
80 is provided to polarize the light incident on the liquid crystal cell 300, adjust the brightness of the light that is polarized and changed by the liquid crystal layer 370, reflected by the reflector 350 and emitted. The liquid crystal cell 300 further includes a color filter (not shown) for displaying a color image.

The liquid crystal layer 370 can be filled as a liquid crystal having a positive or negative dielectric anisotropy.
When the liquid crystal is filled as a liquid crystal having a positive dielectric anisotropy, the compensation film (25 in FIGS. 5 and 6) according to the second embodiment of the present invention is provided on the front and / or back of the liquid crystal cell 300.
(0) is desirable.

The reflection plate 350 reflects the light transmitted through the liquid crystal layer 370 and enters the liquid crystal layer 370 and returns the reflected light to the liquid crystal layer 370. Accordingly, as described above, the incident light may be polarized using one polarizing plate 380, and the brightness of the light emitted from the liquid crystal layer 370 may be adjusted. In addition, as described above, in the case of the reflection type liquid crystal display device having the reflection plate 350, the surface light source device is unnecessary.

In the liquid crystal display device according to the third embodiment of the present invention as described above, the light was passed through the polarizing plate 380,
The light incident on the liquid crystal cell 300 changes its polarization state while passing through the liquid crystal layer 370, and is reflected by the reflection plate 350, and then changes its polarization state while passing through the liquid crystal layer 370 again. The amount of light that varies depends on the molecular arrangement of the liquid crystal.

At this time, in the liquid crystal display device according to the third embodiment of the present invention, the arrangement of the liquid crystal molecules by the applied voltage is such that the liquid crystal layer 370 is filled with a negative liquid crystal having a dielectric anisotropy. 3 and 4 are the same as those in FIGS. 3 and 4, and when the liquid crystal layer 370 is filled with a positive liquid crystal having dielectric anisotropy, the description is the same as that in FIGS. I do.

On the other hand, in the first, second, and third embodiments of the present invention, the liquid crystal molecules are substantially vertically aligned in at least one direction with respect to the first alignment film 150, and the second alignment film 160 On the other hand, since the liquid crystal molecules are substantially horizontally aligned in an arbitrary direction, the reaction time is about 10 ms faster than the existing TN type liquid crystal cell (1 in FIG. 9). The light transmittance was approximately 70% at a viewing angle of ± 60 ° in the vertical and horizontal directions, and the angle dependency of the contrast was improved by approximately 85% or more at ± 60 °.

Hereinafter, a method and apparatus for treating the surface of an alignment film for radially aligning liquid crystals will be described.

According to the present invention, an alignment film made of a photo-alignable polymer is formed on a substrate, and a mask having a plurality of light transmitting regions is positioned on the alignment film. The surface of the alignment film is treated by radially irradiating the alignment film through the process. When the liquid crystal is aligned on the alignment film having been subjected to the surface treatment, the liquid crystal is radially aligned in the light transmission region unit. Therefore, if the light transmission region has a size of substantially a single pixel, the liquid crystal can be radially aligned in pixel units.

FIG. 8 shows an alignment film surface treatment apparatus according to an embodiment of the present invention for irradiating the alignment film with the polarized light as described above.

Referring to the drawing, the light emitted from the light source unit 410 passes through the rotating member 430 and the mask 450 and the substrate 40
Irradiation is performed on the alignment film 405 made of a photo-alignable polymer.
Here, the member number 403 is a transparent electrode (130, 140 in FIG. 1) formed in a predetermined pattern on the substrate 400.

The mask 450 has a plurality of light transmitting regions 451 arranged two-dimensionally. It is preferable that the light transmitting region 451 has a substantially pixel size so that the alignment film 405 is radially irradiated with light in pixel units. In addition, the size of the light transmitting region 451 varies depending on the radial alignment unit of the liquid crystal.

The light source unit 410 is a light source (not shown) for generating light in a predetermined wavelength range, preferably, ultraviolet light.
And at least one optical device (not shown) for converting the light emitted from the light source into parallel light to make the intensity distribution uniform. For example, the light source unit 410 includes a lamp and a reflector (not shown) that surrounds one side of the lamp and reflects divergent light incident from the lamp side to convert it into parallel light. Here, since the light source unit 410 is well known in the field of an apparatus for treating an alignment film, its illustration and detailed description are omitted.

The light source unit 410 is attached to the rotating member 430.
At least one slit 431 for passing the light emitted from is formed in the radial direction. The light transmission slit 431 may be formed in a cross shape or the like crossing the rotation axis 430a of the rotation member 430. Meanwhile, the rotating member 430
Is integrally provided with a polarizer 435 for transmitting light of one polarization. The polarizer 435 is provided on the side of the rotating member 430 toward the light source unit 410 or the side toward the mask 450, and its polarization direction is arranged in the longitudinal direction of the light transmission slit 431 or with respect to the longitudinal direction. It is arranged at a predetermined angle.

Accordingly, when the rotation member 430 is rotated by the driving of a driving source (not shown), the light transmitting position is rotated, that is, the light is polarized on the alignment film 405 in a pixel-by-pixel manner in the form of a spoke wheel rotation. Light is emitted. Therefore, each pixel is irradiated with polarized light in a radial manner.

Hereinafter, the process of surface-treating the alignment film to radially align the liquid crystal will be described.

First, an alignment film 405 made of a photo-alignable polymer
Is prepared. The substrate 400 is placed so that the surface on which the alignment film 405 is formed faces the alignment film surface treatment apparatus according to the present invention.
Position.

Then, the light source unit 410 is operated,
When the rotating member 430 integrated with the polarizer 435 is rotated, the light passing through the light source unit 410 is changed by the rotation of the light transmission slit 431, and the transmitted light is oriented through the mask 450. The film 405 is irradiated in the form of substantially rotating spoke wheels in pixel units.

Accordingly, the irradiated polarized light causes a radial anisotropic photoreaction on the alignment film 405 on a pixel basis, so that the liquid crystal is radially aligned on a pixel basis.

On the other hand, the liquid crystal radially aligned in pixel units by the surface treatment method and apparatus for an alignment film according to the present invention as described above has a random alignment when viewed as a whole screen.

[0055]

In the liquid crystal display device according to the present invention as described above, the liquid crystal molecules are substantially vertically aligned in at least one direction in the first alignment film, and the liquid crystal molecules are randomly and substantially horizontally aligned in the second alignment film. Therefore, a wide viewing angle can be realized, and the angle dependence of the contrast is greatly improved.

At this time, the random alignment of the liquid crystal molecules in the second alignment film, particularly the radial alignment in pixel units, is performed by the surface treatment method and apparatus of the alignment film according to the present invention.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a liquid crystal display device according to a first embodiment of the present invention.

FIGS. 2A and 2B are partial perspective views in which portions A and B are enlarged in the liquid crystal display device of FIG.

FIG. 3 is a cross-sectional view schematically showing a case where no voltage is applied to the liquid crystal display device of FIG.

4 is a cross-sectional view schematically showing a case where a voltage is applied to the liquid crystal display device of FIG.

FIG. 5 is a sectional view schematically showing a liquid crystal display device according to a second embodiment of the present invention.

FIG. 6 is a sectional view schematically showing a liquid crystal display device according to a second embodiment of the present invention.

FIG. 7 is a perspective view schematically showing a liquid crystal display device according to a third embodiment of the present invention.

FIG. 8 is a drawing schematically showing a configuration of a surface treatment apparatus for an alignment film according to an embodiment of the present invention.

FIG. 9 is a view schematically showing a conventional TN type liquid crystal display device.

[Explanation of symbols]

 100, 200, 300 Liquid crystal cells 110, 120 First and second substrates 130, 140 Electrodes 150, 160 First and second alignment films 170, 270, 370 Liquid crystal layer 180, 380 Polarizer 190 Analyzer 250 Compensation film 350 Reflection Plate 400 Substrate 403 Transparent electrode 405 Alignment film 410 Light source unit 430 Rotating member 430a Rotating axis 431 Slit 435 Polarizer 450 Mask 451 Light transmission area

Claims (17)

[Claims] 1. A pair of substrates having a closed space into which liquid crystal is injected, electrodes formed on inner surfaces of the substrates facing each other in the closed space, and an inner surface formed on one side on which the electrodes are formed. A first alignment film for orienting the liquid crystal in at least one direction, a second alignment film formed on the other inner surface on which the electrode is formed to orient the liquid crystal in an arbitrary direction, and the liquid crystal filled in the closed space A liquid crystal display device comprising: a layer; 2. The liquid crystal display device according to claim 1, wherein the liquid crystal is radially aligned in each pixel in the second alignment film. 3. The liquid crystal display device according to claim 1, wherein the liquid crystal molecules in the first alignment film are aligned substantially vertically, and the liquid crystal molecules in the second alignment film are aligned substantially horizontally. 4. The tilt angle of the liquid crystal molecules in the first alignment film is 70 ° to 90 ° and / or -90 ° to -7.
4. The liquid crystal display device according to claim 3, wherein the angle is 0 [deg.]. 5. The liquid crystal display device according to claim 3, wherein the tilt angle of the liquid crystal molecules in the second alignment film is approximately −25 ° to 25 °. 6. The liquid crystal display device according to claim 1, wherein the liquid crystal layer is made of liquid crystal having a negative dielectric anisotropy. 7. The liquid crystal display device according to claim 1, wherein the liquid crystal layer is made of liquid crystal having a positive dielectric anisotropy. 8. The liquid crystal display device according to claim 7, further comprising a compensation film for compensating a viewing angle on a front surface of one of the substrates. 9. The liquid crystal display device according to claim 8, wherein the compensation film is a biaxial film. 10. The liquid crystal display device according to claim 1, further comprising a reflector between the substrate and the liquid crystal layer. 11. A step of preparing a substrate on which an alignment film made of a photo-alignment polymer is formed; a step of positioning a mask having a plurality of light transmission region patterns on the alignment film; Irradiating the alignment film with light that is radially polarized in units of the light transmitting regions through a mask. 12. The light adjusting means comprises: a rotating member having a light transmitting slit formed in a radial direction thereof; a light source unit for irradiating the rotating member with light; and the light source corresponding to the light transmitting slit. And a polarizer disposed between the unit and the alignment film. The light emitted from the light source unit and polarized by the polarizer is radially transmitted to the alignment film by the rotation of the rotating member in units of the light transmission area. The surface treatment method for an alignment film according to claim 11, wherein the surface of the alignment film is irradiated. 13. The method according to claim 12, wherein the polarizer is provided integrally with the rotating member. 14. The alignment film according to claim 11, wherein the light transmission region of the mask has substantially the size of a pixel so that light is radially irradiated to the alignment film in pixel units. Surface treatment method. 15. A light source, a rotating member having a slit for passing light emitted from the light source formed in a radial direction thereof, and a light source and a photo-alignable polymer corresponding to the light transmitting slit. A polarizer disposed between the alignment films, comprising: a mask having a plurality of light transmitting regions disposed between the rotating member and the alignment film, and is irradiated from the light source by rotation of the rotating member, The surface treatment of the alignment film, wherein the light polarized by the polarizer is radially applied to the alignment film through the mask in units corresponding to the light transmitting regions. 16. The surface treatment treatment of an alignment film according to claim 15, wherein the polarizer is provided integrally with the rotating member. 17. The alignment film according to claim 15, wherein a light transmission region of the mask has a size of substantially a pixel so that light is radially irradiated to the alignment film in pixel units. Surface treatment treatment.