TW201331682A - Fabricating method of optical film, optical film, mask and fabricating apparatus of optical film - Google Patents

Abstract

A fabricating method of an optical film has an aligning film, and a plurality of first aligning areas aligned in a first aligning direction and a plurality of second aligning areas aligned in a second aligning direction and crossed to the first aligning direction are arranged on the aligning film alternatively, and the method includes: a first aligning step for irradiating a first polarized light to the aligning film through a first mask area to form the plurality of first aligning areas, wherein a plurality of first light penetration areas for penetrating the first polarized light and a plurality of first light shielding areas for shielding the first polarized light are arranged on the first mask area along an arranging direction; and a second aligning step for irradiating a second polarized light having a polarized direction different from the first polarized light to the second aligning area and at least one portion of the first aligning area continued with the second aligning area in the arranging direction to form the plurality of second aligning areas.

Description

Method for producing optical film, optical film, mask, and optical film manufacturing device

The present invention relates to a method for producing an optical film, an optical film, a mask, and an apparatus for producing an optical film. The present invention relates to a liquid crystal alignment agent and a method of forming a liquid crystal alignment film.

A known method for producing an optical film has an alignment film formed with two alignment regions having mutually different alignment directions (for example, Patent Document 1). In the method for producing an optical film, polarized light having different polarization directions is irradiated to the alignment film in a transmissive region different from each other in the width direction of the film, thereby producing an optical film in which two kinds of alignment regions are formed.

Patent Document 1: US Patent Application Publication No. 2011/0217638

However, the film formed with the alignment film by the above-described production method generates ruthenium or the like during transportation. Therefore, when polarized light of different polarization directions is irradiated to the same region of the alignment film, a part of the alignment film is not irradiated with polarized light. This causes a problem that it is difficult to seamlessly align the alignment regions on the alignment film.

According to a first aspect of the present invention, there is provided a method of producing an optical film, wherein the optical film has an alignment film on which a plurality of first alignment regions aligned in a first alignment direction are alternately arranged and aligned with the first a plurality of second alignment regions in a second alignment direction intersecting the alignment direction, the manufacturing method comprising: a first alignment step of: irradiating the alignment film with the first polarization through the first mask region to form a plurality of first alignment regions, at the first In the mask region, a plurality of first transmission regions through which the first polarized light is transmitted and a plurality of first light blocking regions that block the first polarized light are alternately arranged in the arrangement direction; And a second alignment step of: illuminating at least a portion of the first alignment region and the first alignment region continuous with the second alignment region in the arrangement direction with a second polarization having a polarization direction different from the first polarization to form a plurality of Second alignment area.

According to a second aspect of the present invention, there is provided an optical film produced by the method for producing an optical film described above, wherein the first alignment region and all of the adjacent second alignment regions are in contact with each other.

A third aspect of the present invention provides a mask including: a first mask region in which a plurality of first transmission regions through which the first polarized light is transmitted and a plurality of first portions that block the first polarized light are alternately arranged in the arrangement direction a light shielding region; and a second mask region formed with a second transmission region that transmits a second polarization having a polarization direction different from a polarization direction of the first polarization; and the second transmission region is from the first transmission region in the arrangement direction A portion extends at least to a portion of the adjacent first transmission region, and is formed at a position that does not overlap the plurality of first transmission regions and the plurality of first light shielding regions in a direction perpendicular to the arrangement direction.

According to a fourth aspect of the present invention, there is provided an apparatus for manufacturing an optical film, comprising: the mask; and a conveying unit configured to convey an alignment film on a side of the mask in a direction intersecting the arrangement direction; the first polarization output unit And a second polarized light output portion for illuminating the alignment film with the second polarized light through the second transmission region.

Further, the summary of the above invention does not cite all the essential features of the present invention, and sub-combinations of the feature sets may also constitute the invention.

10‧‧‧Optical film manufacturing equipment

12‧‧‧ Roll

14‧‧‧Alignment film coating department

16‧‧‧Alignment film drying department

18‧‧‧Exposure Department

20‧‧‧Liquid film coating department

22‧‧‧Liquid Crystal Membrane Alignment Department

24‧‧‧Solid film hardening department

26‧‧‧Separation membrane supply department

28‧‧‧roll

32‧‧‧Upstream side driven roller

34‧‧‧Polar light source

38‧‧‧ mask

40‧‧‧ Mask Keeping Department

42‧‧‧ downstream side driven roller

44‧‧‧Upstream side tension roller

46‧‧‧ downstream tension roller

50‧‧‧First polarized light output

52‧‧‧Second polarized light output

56‧‧‧ mask substrate

58‧‧‧Lighting layer

62‧‧‧First transmission area

66‧‧‧second transmission area

82‧‧‧First mask area

84‧‧‧Second mask area

90‧‧‧ film

92‧‧‧Separation membrane

100‧‧‧Optical film

102‧‧‧Resin substrate

104‧‧‧First Polarization Modulation

106‧‧‧Second Polarization Modulation

110‧‧‧ arrow

112‧‧‧ arrow

114‧‧‧ arrow

116‧‧‧ arrow

120‧‧‧Alignment film

122‧‧‧Liquid film

124‧‧‧First alignment area

126‧‧‧Second alignment area

128‧‧‧First LCD area

130‧‧‧Second liquid crystal area

138‧‧‧ mask

150‧‧‧Three-dimensional image display device

152‧‧‧Light source

154‧‧‧Image Output Department

158‧‧‧Optical functional film

164‧‧‧Polar plate

166‧‧‧ Keep the substrate

168‧‧‧Image Generation Department

170‧‧‧Maintaining the substrate

174‧‧‧Polar plate

178‧‧‧Image generation unit for right eye

180‧‧‧Image generation unit for the left eye

182‧‧‧First mask area

184‧‧‧Second mask area

190‧‧‧ polarized glasses

192‧‧‧right eye lens

194‧‧‧Left eye lenses

238‧‧‧ mask

282‧‧‧First mask area

338‧‧‧ mask

366‧‧‧second transmission area

384‧‧‧second mask area

438‧‧‧ mask

482‧‧‧First mask area

484‧‧‧Second mask area

938‧‧‧ mask

962‧‧‧First transmission area

966‧‧‧second transmission area

982‧‧‧First mask area

984‧‧‧Second mask area

Fig. 1 is an overall plan view of an optical film 100 according to the present embodiment.

Fig. 2 is a longitudinal sectional view taken along line II-II of Fig. 1.

Fig. 3 is an exploded perspective view of the stereoscopic image display device.

Fig. 4 is a view showing the overall configuration of an optical film manufacturing apparatus 10 according to the present embodiment.

Fig. 5 is an overall perspective view of an exposure portion.

FIG. 6 is a plan view of the mask 38.

Fig. 7 is a longitudinal sectional view of the mask 38 taken along the line VII-VII of Fig. 6.

FIG. 8 is a plan view of another mask 138.

FIG. 9 is a plan view of another mask 238.

FIG. 10 is a plan view of another mask 338.

Figure 11 is a plan view of another mask 438.

Figure 12 is a plan view of a mask 938 for a comparative example.

Fig. 13 is a photograph of Comparative Example 1 in which the first and second unexposed regions are formed on the alignment film 120 except for the first alignment region 124 and the second alignment region 126.

Fig. 14 is a photograph of Comparative Example 2 in which almost no unexposed regions were formed on the alignment film 120.

Figure 15 is a photograph of the optical film 100 of Example 8.

Fig. 16 is a view showing the results of comprehensive determination of the alignment states of Examples 1 to 19.

The present invention is described below by the embodiments of the invention, but the following embodiments are not intended to limit the invention as claimed. Further, not all of the feature combinations described in the embodiments are essential features of the invention.

Fig. 1 is a plan view showing the entire optical film 100 of the present embodiment. The optical film 100 is manufactured according to the method of producing an optical film according to the present embodiment. The optical film 100 is provided on the image output side of the image generating unit of the stereoscopic image display device, and outputs an image for the right eye and an image for the left eye.

The optical film 100 is formed in a rectangular shape having a side of several centimeters to several meters. As shown in FIG. 1, the optical film 100 has a resin substrate 102, a first polarization modulation section 104, and a second polarization modulation section 106.

The resin substrate 102 is formed by cutting a resin-made elongated film to be described later into a predetermined length. The resin substrate 102 transmits light. An example of the thickness of the resin substrate 102 is 50 μm to 100 μm. The resin substrate 102 supports the first polarization modulation unit 104 and the second polarization modulation unit 106. The resin substrate 102 can be made of a cycloolefin-based film. As the cycloolefin film, a cycloolefin polymer (=COP) can be used, and a cycloolefin copolymer (=COC) which is a copolymer of a cycloolefin polymer is more preferable. As the COP film, a ZEONOR film ZF14 manufactured by Zeon Corporation of Japan can be exemplified. In addition, the resin substrate 102 may be made of a material containing cellulose triacetate (=TAC). The TAC film may, for example, be FUJITACT 80SZ and TD80UL manufactured by Fujifilm Corporation. Further, when a cycloolefin film is used, it is preferable to use a film having a high toughness from the viewpoint of the vulnerability.

The first polarization modulation unit 104 and the second polarization modulation unit 106 are formed in the same shape in plan view. The first polarization modulation unit 104 and the second polarization modulation unit 106 are rectangular shapes extending in the longitudinal direction of the resin substrate 102 . The longitudinal direction of the resin substrate 102 referred to herein is a horizontal direction when the optical film 100 is used for stereoscopic image display. Therefore, the short side direction of the resin substrate 102 is When the optical film 100 is used for stereoscopic image display, it becomes a vertical direction. The first polarization modulation unit 104 and the second polarization modulation unit 106 are alternately arranged in the vertical direction while being in contact with each other. Further, the first polarization modulation unit 104 and the second polarization modulation unit 106 may be alternately arranged in the horizontal direction.

The first polarization modulation unit 104 and the second polarization modulation unit 106 are configured to modulate the polarization state of the transmitted polarized light. The first polarization modulation unit 104 and the second polarization modulation unit 106 have a phase difference function of, for example, a quarter-wave plate. Further, the first polarization modulation unit 104 and the second polarization modulation unit 106 may have a phase difference function of a half wavelength plate. The first polarization modulation unit 104 has, for example, an optical axis parallel to the arrow 110 described at the right end of the first polarization modulation unit 104 in FIG. 1 . According to this, for example, when there is a linear polarization input having a polarization direction rotated by 45° from the arrow 110, the first polarization modulation unit 104 adjusts the polarization to a circularly polarized light having a right-handed polarization direction as indicated by the adjacent arrow 112. And output. The second polarization modulation unit 106 has, for example, an optical axis perpendicular to the optical axis of the first polarization modulation unit 104, and the optical axis is parallel to the arrow 114 at the right end of the second polarization modulation unit 106 shown in FIG. According to this, for example, when there is a linear polarization input having a polarization direction rotated by 45° from the arrow 110, the second polarization modulation unit 106 adjusts the polarization to a circularly polarized light having a left-handed polarization direction as indicated by the adjacent arrow 116. Make the output. Further, an example of the optical axis is a phase lead axis or a phase backward axis.

As a result, even if the linearly polarized light having the same polarization direction is input to the first polarization modulation unit 104 and the second polarization modulation unit 106, the polarization direction of the polarization outputted by the second polarization modulation unit 106 is modulated by the first polarization. The polarization directions of the polarized lights output by the portion 104 are also different. For example, the polarization direction of the polarized light output by the second polarization modulation unit 106 is circularly polarized light that rotates in the opposite direction to the polarization direction of the polarization outputted by the first polarization modulation unit 104.

Fig. 2 is a longitudinal sectional view taken along line II-II of Fig. 1. As shown in FIG. 2, each of the first polarization modulation section 104 and the second polarization modulation section 106 has an alignment film 120 and a liquid crystal film 122.

The alignment film 120 is formed on the surface of the resin substrate 102. The alignment film 120 can be applied to a known photo-alignment compound. The photo-alignment compound is a material in which the molecules are regularly aligned along the polarization direction of the linearly polarized light when irradiated with linearly polarized light such as ultraviolet rays. Further, the photo-alignment compound has a function of arranging molecules of the liquid crystal film 122 formed on itself along their own alignment. Examples of the photo-alignment compound include compounds such as a photodecomposition type, a photodimerization type, and an optically anisotropic type. The alignment film 120 has a plurality of first alignment regions 124 and a plurality of second alignment regions 126. The plurality of first alignment regions 124 and the plurality of second alignment regions 126 are arranged in the alignment direction Arrange for. The arrangement direction here is parallel to the vertical direction. The first alignment region 124 and the adjacent all second alignment regions 126 are in contact with each other. The first alignment area 124 constitutes a part of the first polarization modulation unit 104. The first alignment region 124 is aligned in a direction corresponding to the optical axis of the first polarization modulation portion 104. The second alignment region 126 constitutes a part of the second polarization modulation portion 106. The second alignment region 126 is aligned in a direction perpendicular to the alignment direction of the first alignment region 124, that is, in a direction corresponding to the optical axis of the second polarization modulation portion 106.

The liquid crystal film 122 is formed on the alignment film 120. The liquid crystal film 122 can be composed of a liquid crystal polymer which can be cured by ultraviolet rays or heating. The liquid crystal film 122 has a first liquid crystal region 128 and a second liquid crystal region 130. The first liquid crystal region 128 constitutes a part of the first polarization modulation unit 104. The first liquid crystal region 128 is formed on the first alignment region 124. The molecules of the first liquid crystal region 128 are aligned along the alignment of the first alignment regions 124. The second liquid crystal region 130 constitutes a part of the second polarization modulation unit 106. The second liquid crystal region 130 is formed on the second alignment region 126. The molecules of the second liquid crystal region 130 are aligned along the alignment of the second alignment region 126.

Fig. 3 is an exploded perspective view of the stereoscopic image display device. As shown by the arrow in Fig. 3, the direction in which the image is output is set to the front of the stereoscopic image display device as the direction in which the user is located. As shown in FIG. 3, the stereoscopic image display device 150 includes a light source 152, an image output portion 154, an optical film 100, and an optical functional film 158.

The light source 152 illuminates the white unpolarized light with a substantially uniform intensity in the plane. The light source 152 is disposed at the rear of the stereoscopic image display device 150 from the user's perspective. A light source composed of a diffuser plate and a cold cathode fluorescent lamp (CCFL) or a light source composed of a prism sheet and a light emitting diode (LED) may be applied to the light source 152, and the organic light source may be used. A surface light source such as EL (Electro-Luminescence).

The image output unit 154 is disposed in front of the light source 152. The image output unit 154 outputs an image based on light from the light source 152. The image output unit 154 includes a polarizing plate 164, a holding substrate 166, an image generating unit 168, a holding substrate 170, and a polarizing plate 174.

The polarizing plate 164 is disposed between the light source 152 and the holding substrate 166. An example of the material constituting the polarizing plate 164 is a resin containing polyvinyl alcohol (PVA: Polyvinyl alcohol). The polarizing plate 164 has a transmission axis that is inclined by 45° from the horizontal direction and an absorption axis that is perpendicular to the transmission axis. As a result, in the unpolarized light that is output from the light source 152 and incident on the polarizing plate 164, the component whose vibration direction is parallel to the transmission axis of the polarizing plate 164 is transmitted, and the component parallel to the absorption axis is absorbed and blocked. Therefore, the light output from the polarizing plate 164 is linearly polarized with the transmission axis of the polarizing plate 164 as the polarization direction.

The holding substrate 166 is disposed between the polarizing plate 164 and the image generating portion 168. The holding substrate 166 can be applied to a transparent glass plate. Further, in addition to the glass plate, the holding substrate 166 can also be applied to a transparent composite sheet using a transparent composite material containing a transparent resin and a glass cloth. According to this, it is possible to achieve weight reduction and flexibility of the stereoscopic image display device 150. The polarizing plate 164 is held by the adhesive behind the holding substrate 166.

The image generating portion 168 is disposed and held between the holding substrate 166 and the holding substrate 170. The image generation unit 168 has a plurality of pixels (=pixels) for generating an image. A plurality of pixels are two-dimensionally arranged at a certain pitch in the vertical direction and the horizontal direction. A pixel is a unit for performing image processing and is used to output color information of hue and gradation. Each pixel has three sub-pixels (=sub pixels). Each of the sub-pixels has a transparent electrode formed in front of and behind the liquid crystal portion and the liquid crystal portion. A transparent electrode is used to apply a voltage to the liquid crystal portion. The liquid crystal portion of the sub-pixel to which the voltage is applied rotates the polarization direction of the linearly polarized light by 90°. The three sub-pixels included in each pixel have a red color filter, a green color filter, and a blue color filter, respectively. By controlling the voltage applied to the transparent electrode of the sub-pixel, red, green, and blue light output from the sub-pixel can be enhanced or attenuated to form an image.

The image generating unit 168 includes a right-eye image generating unit 178 for generating a right-eye image and a left eye for generating a left-eye image, as indicated by “R” and “L” in FIG. The image generation unit 180 is used. The right-eye image generating unit 178 and the left-eye image generating unit 180 are formed in a rectangular shape extending in the horizontal direction. The right-eye image generating unit 178 and the left-eye image generating unit 180 are alternately arranged in the vertical direction.

The holding substrate 170 is disposed between the image generating portion 168 and the polarizing plate 174. The holding substrate 166 and the holding substrate 170 sandwich the image generating unit 168. The holding substrate 170 is made of the same material as the holding substrate 166. The polarizing plate 174 is held by an adhesive on the front side of the holding substrate 170.

The polarizing plate 174 is placed between the holding substrate 170 and the optical film 100. The polarizing plate 174 is bonded to the side opposite to the side on which the image forming portion 168 is held by the holding substrate 170 by an adhesive. The polarizing plate 174 is made of a resin containing PVA (polyvinyl alcohol). The thickness of the polarizing plate 174 is preferably thin. The thickness of the polarizing plate 174 is, for example, 100 μm to 200 μm. The polarizing plate 174 has a transmission axis and an absorption axis perpendicular to the transmission axis. The transmission axis of the polarizing plate 174 is perpendicular to the transmission axis of the polarizing plate 164 straight. As a result, the linearly polarized light that has been rotated by 90° in the polarization direction processed by the image generating unit 168 passes through the polarizing plate 174 to become image light, thereby forming an image. On the other hand, the linearly polarized light whose polarization direction is not processed by the image generation unit 168 is blocked by the polarizing plate 174. As a result, the image output unit 154 outputs image light composed of polarized light whose polarization direction is parallel to the transmission axis of the polarizing plate 174.

The optical film 100 is bonded to the front side of the polarizing plate 174 of the image output portion 154 by an adhesive. In order to suppress the dimensional change of the optical film 100, the thickness of the optical film 100 is preferably relatively thin. For example, the thickness of the optical film 100 is preferably from 50 μm to 200 μm.

The first polarization modulation portion 104 and the second polarization modulation portion 106 of the optical film 100 are disposed on the rear surface of the resin substrate 102. The first polarization modulation unit 104 has substantially the same shape as the right-eye image generation unit 178 of the image generation unit 168. The first polarization modulation unit 104 is provided in front of the right-eye image generation unit 178. As a result, the right-eye image light composed of the linearly polarized light that is output from the right-eye image generating unit 178 and transmitted through the polarizing plate 174 is incident on the first polarization modulation unit 104. The first polarization modulation unit 104 converts the incident right-eye image light into a right-handed circular polarization and outputs it. The second polarization modulation unit 106 has substantially the same shape as the left-eye image generation unit 180 of the image generation unit 168. The second polarization modulation unit 106 is provided in front of the left-eye image generation unit 180. As a result, the left-eye image light composed of the linearly polarized light that is output from the left-eye image generating unit 180 and transmitted through the polarizing plate 174 is incident on the second polarization adjusting unit 106. The second polarization modulation unit 106 adjusts the incident left-eye image light into a left-hand circular polarization and outputs it. Therefore, the first polarization modulation unit 104 and the second polarization modulation unit 106 convert the linear polarization of the same polarization direction constituting the right-eye image and the left-eye image into circularly polarized light having different polarization directions, and then output the same. .

The optical functional film 158 is disposed in front of the optical film 100. An example of the optical function film 158 is an anti-reflection film or an anti-reflection film for reducing or suppressing reflection of output light from external illumination or the like. According to this, the optical functional film 158 supplies an image in which less external light is mixed to the user. Another example of the optical functional film 158 is an anti-glare film for suppressing glare, a hard coat film for preventing surface damage, and the like. Alternatively, the optical functional film 158 may be omitted.

The polarized glasses 190 used by the user when viewing a stereoscopic image have a right-eye lens 192 and a left-eye lens 194. The right-eye lens 192 allows only right-handed circularly polarized light to pass through. The left-eye lens 194 allows only left-handed circularly polarized light to pass through. According to this, the right eye of the user can only recognize the image for the right eye output from the first polarization modulation unit 104, and the left eye of the user can recognize only the image for the left eye output from the second polarization modulation unit 106. . Thereby enabling the user to view the stereoscopic image.

Fig. 4 is a view showing the overall configuration of an optical film manufacturing apparatus 10 according to the present embodiment. The upper and lower directions indicated by the arrows in FIG. 4 are referred to as the vertical direction of the optical film manufacturing apparatus 10. In addition, the upstream and downstream are upstream and downstream in the conveying direction. Further, the conveying direction is the same direction as the longitudinal direction of the film 90, and is perpendicular to the arrangement direction and the width direction.

As shown in FIG. 4, the optical film manufacturing apparatus 10 includes a delivery roller 12, an alignment film application unit 14, an alignment film drying unit 16, an exposure unit 18, a liquid crystal film application unit 20, a liquid crystal film alignment unit 22, and a liquid crystal film curing unit 24. The separation membrane supply unit 26 and the take-up roller 28 are provided.

The delivery roller 12 is provided on the most upstream side of the transport path of the film 90. The film 90 for supply is wound around the outer circumference of the feed roller 12. The delivery roller 12 is rotatably supported. Thereby, the delivery roller 12 is kept capable of feeding the film 90. The delivery roller 12 may be configured to rotate by a drive mechanism such as a motor, or may be configured to follow the rotation of the take-up roller 28. Alternatively, a mechanism for driving the film 90 may be provided in the middle of the transport path.

The alignment film application portion 14 is provided on the upstream side of the exposure portion 18 and serves as the downstream side of the delivery roller 12. The alignment film application portion 14 is provided above the transport path of the film 90 to be transported. The alignment film application unit 14 is for supplying and applying a liquid alignment film 120 as an example of an exposure material to the upper surface of the film 90.

The alignment film drying unit 16 is provided on the downstream side of the alignment film application unit 14. The alignment film drying unit 16 dries the alignment film 120 coated on the inner film 90 by heating, light irradiation, or air blowing.

The exposure unit 18 is provided on the downstream side of the alignment film drying unit 16 . The exposure unit 18 includes an upstream side driven roller 32, a polarization light source 34, a mask 38, a mask holding unit 40, a downstream side driven roller 42, a pair of upstream tension rollers 44, and a downstream tension roller 46. The alignment film 18 applied to the film 90 via the mask 38 is irradiated with the polarized light output from the polarization light source 34. According to this, the exposure portion 18 aligns the alignment film 120 to form a pattern. An example of the polarized light output from the polarized light source 34 is ultraviolet light having a wavelength of 280 nm to 340 nm.

The liquid crystal film application unit 20 is provided on the downstream side of the exposure unit 18. The liquid crystal film application unit 20 is provided above the transport path of the film 90. The liquid crystal film application unit 20 is for supplying and coating the liquid crystal film 122 onto the alignment film 120 formed on the film 90.

The liquid crystal film alignment portion 22 is provided on the downstream side of the liquid crystal film application portion 20. The liquid crystal film alignment portion 22 is for drying the liquid crystal film 122 formed on the internal alignment film 120 by heating, light, or air blowing while being aligned in the alignment direction of the alignment film 120.

The liquid crystal film hardening portion 24 is provided on the downstream side of the liquid crystal film alignment portion 22. The liquid crystal film hardening portion 24 is for curing the liquid crystal film 122 by irradiating ultraviolet rays. Thereby, the alignment of the molecules of the liquid crystal film 122 aligned in the alignment direction of the alignment film 120 is fixed.

The separation membrane supply unit 26 is provided between the liquid crystal film curing unit 24 and the take-up roller 28 . The separation membrane supply unit 26 supplies the separation membrane 92 to the liquid crystal film 122 of the film 90 and bonds them. The separation membrane 92 allows easy separation between the wound membranes 90. Further, the separation membrane supply unit 26 may be omitted.

The take-up roller 28 is an example of a conveyance unit. The take-up roller 28 is provided on the most downstream side of the conveyance path as the downstream side of the liquid crystal film hardening portion 24. The take-up roller 28 is rotatably supported. The winding roller 28 winds up the film 90 on which the alignment film 120 and the liquid crystal film 122 are formed and patterned. Accordingly, the take-up roller 28 conveys the film 90 on which the alignment film 120 and the liquid crystal film 122 are formed in the transport direction.

FIG. 5 is an overall perspective view of the exposure unit 18. As shown in FIG. 5, the upstream side driven roller 32 is provided on the upstream side of the upstream side tension roller 44 as the downstream side of the alignment film drying section 16. The upstream side driven roller 32 is disposed above the conveying path of the film 90. The upstream side driven roller 32 rotates with the film 90 conveyed below. Further, the upstream side driven roller 32 presses the film 90 being conveyed downward.

The polarized light source 34 is disposed above the transport path of the film 90. The polarization light source 34 has a first polarization output unit 50 and a second polarization output unit 52. The first polarization output unit 50 and the second polarization output unit 52 are provided between the upstream tension roller 44 and the downstream tension roller 46. The second polarization output unit 52 is provided on the downstream side of the first polarization output unit 50. The first polarized light output unit 50 outputs the first polarized light downstream and downward. The first polarized light has a polarization direction corresponding to the alignment of the first alignment region 124. The first polarized light is inclined by 45° from the upper and lower sides toward the upstream side, and then incident on the film 90. The second polarized light output portion 52 outputs the second polarized light upstream and downward. The second polarized light has a polarization direction corresponding to the alignment of the second alignment region 126. The second polarized light is inclined to the downstream side by 45° from the upper and lower sides, and then incident on the film 90. According to this, even if the first polarized light and the second polarized light are reflected by the film 90 and the peripheral device or the like, the probability of returning to the alignment film 120 coated on the film 90 is still low. Thereby, it is possible to suppress the reflected first polarized light and the second polarized light from being irradiated onto an undesired place on the film 90. The illuminance of the first polarized light output by the first polarized light output unit 50 is equal to the illuminance of the second polarized light output by the second polarized light output unit 52. The illuminance referred to herein means the energy per unit area of the output polarized light per unit time, and the unit is mW/cm ² . When the output polarized light is ultraviolet light, the illuminance becomes UV illuminance. An example of the illuminance of the first polarized light and the second polarized light is 78 mW/cm ² .

The polarization direction of the second polarized light output by the second polarized light output portion 52 is converted by the first polarized light The polarization direction of the first polarized light output from the output portion 50 is perpendicular. Further, the polarization direction of the second polarization outputted by the second polarization output unit 52 and the polarization direction of the first polarization output by the first polarization output unit 50 may also intersect at an arbitrary angle. Preferably, a light shielding wall extending in the vertical direction to the mask 38 is provided between the first polarized light output portion 50 and the second polarized light output portion 52. Accordingly, the light shielding walls block the mutual polarization. At this time, the light shielding wall is preferably black for suppressing reflection of the first polarization and the second polarization.

The mask 38 transmits a part of the polarized light output from the polarized light source 34 to block the remaining portion. The film 90 is thereby exposed to a predetermined pattern. The mask 38 is disposed between the polarized light source 34 and the film 90. As an example, the mask 38 may be disposed over a few hundred μm of the film 90. The mask 38 has a mask substrate 56 and a light shielding layer 58. An opening functioning as the first transmission region 62 and an opening functioning as the second transmission region 66 are formed on the light shielding layer 58.

The mask holding portion 40 is held so as to be relatively movable in the width direction perpendicular to the conveying direction with respect to the film 90. The mask holding portion 40 is for holding the mask 38. Thereby, the mask 38 can be moved together with the mask holding portion 40 by a motor, an actuator, or the like.

The downstream side driven roller 42 is provided on the downstream side of the downstream side tension roller 46. The downstream side driven roller 42 is disposed above the conveying path of the film 90. The downstream side driven roller 42 rotates with the film 90 conveyed below. Further, the downstream side driven roller 42 presses the film 90 being conveyed downward.

The upstream side tension roller 44 is provided on the downstream side of the upstream side driven roller 32 as the upstream side of the polarization light source 34 and the mask 38. The downstream side tension roller 46 is provided on the upstream side of the downstream side driven roller 42 as the downstream side of the polarization light source 34 and the mask 38. The upstream side tension roller 44 and the downstream side tension roller 46 are rotatably supported. The upstream tension roller 44 and the downstream tension roller 46 may be configured to be rotatable by a drive motor or the like, or may be configured to be driven by a driving force of the take-up roller 28 or the like.

The upstream side tension roller 44 and the downstream side tension roller 46 are disposed below the transport path. As a result, the upstream tension roller 44 and the downstream tension roller 46 are brought into contact with and pressed against the lower surface of the surface of the alignment film 120 in which the film 90 is not formed on the surface of the film 90. As described above, the film 90 is pressed downward by the upstream side driven roller 32 and the downstream side driven roller 42. Therefore, the upstream side tension roller 44 and the downstream side tension roller 46 apply the tension in the conveyance direction to the film 90 pressed downward.

The upstream side tension roller 44 and the downstream side tension roller 46 are disposed to sandwich the mask 38 therebetween. The upstream side tension roller 44 is disposed closer to the upstream side than the upstream side end portion of the first transmission region 62, The downstream side tension roller 46 is disposed closer to the downstream side than the downstream side end portion of the second transmission region 66. Therefore, the first polarized light and the second polarized light output from the first polarized light output portion 50 and the second polarized light output portion 52 are reduced by the upstream side tension roller 44 and the downstream side tension roller 46 after being transmitted through the film 90, thereby causing the film 90 to be caused. exposure. The distance between the upstream side tension roller 44 and the downstream side tension roller 46 can be shorter than the length in the longitudinal direction of the optical film 100 of several cm or more provided on a general liquid crystal display device. Thereby, the film 90 between the upstream side tension roller 44 and the downstream side tension roller 46 can be given a sufficient tension in the conveying direction.

FIG. 6 is a plan view of the mask 38. Fig. 7 is a longitudinal sectional view taken along line VII-VII of the mask 38 shown in Fig. 6. The arrow displayed in the transmission region of FIG. 6 is an example of the polarization direction of the polarized light transmitted through the transmission region. In FIGS. 6 and 7, the conveying direction means the conveying direction of the film 90, and the width direction means the direction perpendicular to the conveying direction.

As shown in FIGS. 6 and 7, the mask base material 56 of the mask 38 is formed in a rectangular plate shape. The mask substrate 56 is made of a material such as quartz glass. An example of the length of the mask substrate 56 in the transport direction of the film 90 is about 300 mm. In addition, the length of the mask substrate 56 can be appropriately changed corresponding to the width of the film 90. The light shielding layer 58 is formed under the mask substrate 56. The light shielding layer 58 is made of a material that can block light such as chrome. As described above, an opening functioning as the plurality of first transmission regions 62 and second transmission regions 66 is formed on the light shielding layer 58. The region in which the plurality of first transmission regions 62 are formed is the first mask region 82. The region in which the second transmission region 66 is formed is the second mask region 84. The second mask region 84 is disposed closer to the downstream side in the transport direction than the first mask region 82.

The first transmission region 62 is disposed between the first polarized light output portion 50 and the film 90. The first transmission region 62 transmits at least the first polarized light. Thereby, the first polarized light output from the first polarized light output unit 50 is transmitted through the first transmission region 62, and then the alignment film 120 formed on the film 90 is exposed. The plurality of first transmission regions 62 are arranged in the width direction. An example of the length of the first transmission region 62 in the transport direction is 40 mm. An example of the length of the first transmission region 62 in the width direction is 0.2 mm. An example of the distance between the first transmission region 62 and the adjacent first transmission region 62 is 0.2 mm. Between the first transmission region 62 and the adjacent first transmission region 62 is an example of a plurality of first light-blocking regions that shield the first polarized light. That is, in the first mask region 82, the first transmission region 62 and the first light-shielding region are alternately arranged in the width direction in which the writing direction is an example.

The second transmission region 66 transmits at least the second polarized light. The second transmission region 66 is disposed between the second polarized light output portion 52 and the film 90. Thereby the second bias output from the second polarized light output portion 52 is made The light passes through the second transmission region 66 to illuminate the alignment film 120 formed on the film 90.

The second transmission region 66 is formed to extend in the width direction. One end of the second transmission region 66 reaches the first transmission region 62 of one of the plurality of first transmission regions 62 in the width direction. The other end of the second transmission region 66 extends to the outside of the first transmission region 62 at the other end of the plurality of first transmission regions 62, that is, extends to the vicinity of the side surface of the mask substrate 56 than the first transmission region 62 at the other end. . That is, the length of the second transmission region 66 in the width direction is longer than the length from the first transmission region 62 at one end to the first transmission region 62 at the other end. An example of the length of the second transmission region 66 in the width direction is 290 mm. Therefore, the second transmission region 66 is formed at a position overlapping the first transmission region 62 in the width direction. Therefore, the second polarized light transmitted through the second transmission region 66 exposes not only the region that is not exposed by the first polarized light transmitted through the first transmission region 62 but also the region that has been exposed by the first polarized light. As a result, the region that is not exposed by the first polarized light transmitted through the first transmission region 62 is seamlessly exposed by the second polarized light transmitted through the second transmission region 66.

An end portion on the upstream side of the second transmission region 66 is provided closer to the downstream side than an end portion on the downstream side of the first transmission region 62. That is, the second transmission region 66 is formed at a position that does not coincide with the first transmission region 62 and the first light shielding region in the transport direction. The length of the second transmission region 66 in the conveying direction is shorter than the length of the first transmission region 62 in the conveying direction. The length of the second transmission region 66 in the conveying direction is, for example, 13 mm to 43 mm. According to this, even if the illuminance of the first polarized light is equal to the illuminance of the second polarized light, the exposure amount per unit area of the second polarized light irradiated to the alignment film 120 is smaller than the exposure amount per unit area of the first polarized light. Therefore, the second polarized light is less disturbed by the alignment direction of the previously aligned first alignment region 124, so that the first alignment region 124 and the second alignment region 126 conform to the design can be obtained. The exposure amount referred to herein means the integrated value of the illuminance in each unit area region during the irradiation time, and the unit is mJ/cm ² . In addition, the expression of the exposure amount is as follows.

Exposure amount [mJ/cm ² ] = illuminance [mW/cm ² ] × irradiation time [sec]

Further, the first transmission region 62 may be constituted by a polarizing plate that can transmit only the first polarized light. Further, the second transmission region 66 may be composed of a polarizing plate that can transmit only the second polarized light. Accordingly, the second transmission region 66 can suppress the transmission of the second polarized light by the first transmission region 62 while suppressing the transmission of the first polarized light. At this time, the polarized light source 34 can also output non-polarized light.

Hereinafter, a method of manufacturing the optical film 100 will be described. First prepare the roll on the delivery roll 12 strips of film 90. Here, an example of the entire length of the film 90 is about 1000 m. An example of the width of the film 90 is about 1 m. Then, one end of the film 90 is fixed to the take-up roll 28. In this state, the film 90 is disposed to pass through the upper surfaces of the upstream side tension roller 44 and the downstream side tension roller 46.

Then, the take-up roller 28 starts to perform rotational driving. As a result, it is a conveying step of conveying the film 90 from the delivery roller 12 to transport the film 90 in the conveying direction. An example of the conveying speed of the film 90 is 2 m/min to 10 m/min.

The film 90 that has been sent out passes under the alignment film application portion 14. Thereby, the alignment film coating portion 14 applies the alignment film 120 over substantially the entire width direction of the upper surface of the film 90. The application of the alignment film 120 is continuously performed in the conveyance of the film 90. Thus, in addition to a part of both ends, the alignment film 120 is continuously applied over the entire length of the film 90 in the transport direction.

The film 90 coated with the alignment film 120 is transported and passed through the inside of the alignment film drying unit 16. The alignment film 120 coated on the film 90 is thus dried. Thereafter, the film 90 passes through the lower side of the upstream side driven roller 32 and the upper surface of the upstream side tension roller 44.

The region on which the alignment film 120 is coated on the film 90 passes through the lower side of the first transmission region 62 to be the first alignment step. In the first alignment step, the first polarized light illuminates the alignment film 120 through the first mask region 82 in a state where the transport step is continued, thereby forming a plurality of first alignment regions 124. Specifically, the alignment film 120 formed on the region of the film 90 that passes under the first transmission region 62 is exposed by the first polarization emitted from the first polarization output portion 50 and transmitted through the first transmission region 62 of the mask 38. Here, the film 90 is exposed while continuously being conveyed by the take-up roll 28 continuously at a constant speed. Therefore, the first polarized light output from the first polarized light output portion 50 is continuously exposed in the transport direction by the alignment film 120 under the first transmission region 62. Accordingly, the alignment film 120 passing through the region below the first transmission region 62 is exposed to a strip shape having the same width as the first transmission region 62 and extending in the transport direction. According to this, the film 90 is made longer than the length of the irradiation region of the polarized light source 34 of the exposure portion 18 in the transport direction and is exposed without seams. Further, since the alignment film 120 of this region is exposed by the first polarized light output from the first polarized light output portion 50, the alignment film 120 of the region is aligned corresponding to the exposed first polarized light.

Thereafter, the film 90 coated with the region of the alignment film 120 is transported to pass under the second transmission region 66, thereby becoming the second alignment step. In the second alignment step, in a state where the transporting step is continuously performed, the second polarized light is irradiated to the alignment film 120 through the second mask region 84, thereby forming a plurality of second alignment regions 126. Specifically, the second polarized light output unit 52 outputs and transmits the mask. The second polarized light of the second transmission region 66 of the mold 38 illuminates the alignment film 120 of the film 90 formed on the region below the second transmission region 66. Since the film 90 is continuously conveyed, the alignment film 120 of this region is also irradiated with the second polarized light into a strip shape having the same width as the second transmission region 66 and extending in the transport direction.

Here, the second transmission region 66 extends from the outer side of the side of the first transmission region 62 at one end in the width direction on the left side of the paper surface to the side of the right side of the paper surface in the width direction. According to this, the second polarized light illuminates the alignment film 120 from the outer side in the width direction of the first transmission region 62 at one end to the entire width of the first transmission region 62 at the other end. Therefore, the second polarized light not only irradiates the region that is not exposed by the first polarized light, but also irradiates the region that has been exposed by the first polarized light. Accordingly, between the first alignment region 124 aligned by the first polarization and the adjacent first alignment region 124, there is no region that is not irradiated with the second polarized light.

The length of the second transmission region 66 in the conveying direction is shorter than the length of the first transmission region 62 in the conveying direction. Therefore, the exposure amount of the second polarized light irradiated per unit area of the film 90 is smaller than the exposure amount of the first polarized light irradiated per unit area. According to this, it is difficult for the molecules aligned by the first polarized light to change the alignment direction by the second polarized light. Therefore, the alignment film 120 in the region irradiated with the second polarized light without irradiating the first polarized light is aligned corresponding to the second polarized light to be irradiated. Here, the polarization direction of the second polarized light output from the second polarization output unit 52 is perpendicular to the polarization direction of the first polarized light output from the first polarized light output unit 50. Accordingly, the alignment direction of the region aligned by the first polarized light and the alignment direction of the region aligned by the second polarized light are perpendicular to each other. As a result, two patterns including the regions corresponding to the different alignments of the first polarization modulation portion 104 and the second polarization modulation portion 106 are alternately arranged on the alignment film 120.

Here, the film 90 is pressed downward by the upstream side driven roller 32 and the downstream side driven roller 42. According to this, the tension in the conveying direction is imparted to the film 90 between the upstream side tension roller 44 and the downstream side tension roller 46. In addition, since the upstream side tension roller 44 is formed in a cylindrical shape, the movement of the film 90 in the width direction is made small.

Thereafter, the film 90 after the alignment film 120 is exposed is sent to the lower side of the liquid crystal film application portion 20 through the lower side of the downstream side driven roller 42. Accordingly, the liquid crystal film 122 is applied on the upper surface of the alignment film 120. Since the liquid crystal film 122 is continuously applied to the upper surface of the alignment film 120 of the film 90 being conveyed, the liquid crystal film 122 is applied over the entire length of the film 90 in the transport direction. Thereafter, the film 90 coated with the liquid crystal film 122 is transported to pass through the liquid crystal film alignment portion 22. Then, by liquid The crystal film alignment portion 22 heats the liquid crystal film 122 to align the molecules of the liquid crystal film 122 along the alignment of the alignment film 120 formed on the lower surface, and simultaneously performs drying.

Then, the film 90 after the applied liquid crystal film 122 is aligned passes through the liquid crystal film curing portion 24. Then, the liquid crystal film 122 is irradiated with ultraviolet rays to cure the liquid crystal film 122 in a state after being aligned. As a result, the molecules of the liquid crystal film 122 are respectively aligned corresponding to the alignment film 120 passing through the region below the first transmission region 62 and the alignment film 120 passing through the region below the second transmission region 66. As shown in FIGS. 1 and 2, the first polarization modulation portion 104 and the second polarization modulation portion 106 formed by the alignment film 120 and the liquid crystal film 122 are alternately formed in the width direction of the film 90. Then, the separation membrane 92 is supplied onto the upper surface of the liquid crystal film 122 and bonded. Then, the film 90 on which the separation film 92 is attached is taken up by the take-up roll 28.

Thereafter, the film 90 is continuously exposed while the film 90 is being conveyed by the take-up roll 28 until the supply of the film 90 wound on the feed roller 12 is finished. Then, when the film 90 wound on the delivery roller 12 is completely supplied, the manufacturing process of the optical film 100 is completed. Further, the front end of the next new film 90 may be joined to the rear end of the finished film 90 to continuously expose the film 90. Finally, the film 90 is cut into a predetermined length and finally completed after the optical film 100 shown in Figs. 1 and 2 is obtained.

As described above, in the present embodiment, the second transmission region 66 is formed to overlap the first transmission regions 62 in the width direction. According to this, even in the case where, for example, the film 90 on which the alignment film 120 is formed is crotched or curled, the second alignment region 126 can be seamlessly formed between the first alignment regions 124, thereby making the first alignment region 124 And the second alignment region 126 is aligned with the alignment film 120.

In the present embodiment, the length of the second transmission region 66 in the transport direction is shorter than the length of the first transmission region 62 in the transport direction. According to this, even if the illuminance of the first polarized light output by the first polarized light output unit 50 is the same as the illuminance of the second polarized light output by the second polarized light output unit 52, the exposure per unit area of the second polarized light that is irradiated to the alignment film 120 is performed. The amount will also be less than the amount of exposure per unit area of the first polarized light. Therefore, it is possible to suppress the alignment of the first alignment region 124 aligned by the first polarization from being disturbed by the second polarization.

In the present embodiment, the film 90 coated with the alignment film 120 is exposed while being exposed by the first polarized light and the second polarized light. Therefore, the length of the mask 38 in the transport direction can be shortened compared to the lengths of the first polarization modulation portion 104 and the second polarization modulation portion 106 of the optical film 100.

In the present embodiment, the second transmission region 66 is disposed to be larger than the first transmission region 62 Closer to the downstream side. According to this, since the first alignment region 124 can be formed on the alignment film 120 that is not aligned, the energy of the first polarization can be reduced.

In the present embodiment, the width of the first transmission region 62 is shorter than the width of the first alignment region 124. According to this, even if the first polarized light transmitted through the first transmission region 62 is widened, the alignment of the first polarized light with the region other than the first alignment region 124 can be suppressed.

FIG. 8 is a plan view of another mask 138. The first mask region 182 and the second mask region 184 are respectively formed by the mask 138 shown in FIG. According to this, even if one of the first mask region 182 or the second mask region 184 is damaged, it is only necessary to replace or repair the damaged region, so that the maintenance cost of the mask 138 can be reduced. In addition, when the pattern of the first alignment region 124 and the second alignment region 126 is to be changed, the pattern of the first alignment region 124 and the second alignment region 126 can be changed only by replacing the first mask region 182.

FIG. 9 is a plan view of another mask 238. The mask 238 shown in FIG. 9 has only the first mask region 282 and the second mask region is omitted. Therefore, the second polarized light directly illuminates the film 90 without passing through the mask 238. At this time, the illuminance of the second polarized light is set to be smaller than the illuminance of the first polarized light. An example of the illuminance of the second polarized light is such that the alignment of the aligned first alignment regions 124 is not disturbed.

FIG. 10 is a plan view of another mask 338. The second transmission region 366 of the second mask region 384 is divided into a plurality by a mask 338 shown in FIG. In the width direction, each of the second transmission regions 366 extends from a portion of the end of the first transmission region 62 to a portion of the end portion of the adjacent first transmission region 62. In other words, in the width direction, each of the second transmission regions 366 extends from the center of the light shielding layer 58 between the first transmission regions 62 to a portion of the end portion of the first transmission region 62 adjacent to the light shielding layer 58. Further, in the width direction, each of the second transmission regions 366 spans one side of the first transmission region 62 and also spans one side of the adjacent first transmission region 62. Accordingly, both end portions of the respective second transmission regions 366 overlap with the ends of the adjacent first transmission regions 62 in the width direction. Therefore, the second polarized light not only irradiates the region in which the second alignment region 126 is formed, but also irradiates a portion of the first alignment region 124 that is continuous with the second alignment region 126. In other words, the second polarized light traverses the boundary between the first alignment region 124 and the second alignment region 126, and illuminates the continuous region formed by the second alignment region 126 and a portion of the end portions of the first alignment regions 124 on both sides. As a result, even if the film 90 is ejected during transport, the region that is not exposed by the first polarized light can be seamlessly exposed by the second polarized light transmitted through the second transmissive region 366.

FIG. 11 is a plan view of another mask 438. The second mask region 484 is disposed on the upstream side of the first mask region 482 in the transport direction by the mask 438 shown in FIG. According to this, since the first polarized light is irradiated after the second polarized light, the alignment state of the first alignment region 124 can be improved by enhancing the illuminance of the first polarized light to such an extent that the alignment by the second polarized light can be changed. .

The shape, numerical value, number, and the like of the structures described in the above embodiments may be appropriately changed. In addition, a plurality of embodiments may be combined. For example, the illuminance and the exposure amount of the first polarized light and the second polarized light can be appropriately changed. Further, the alignment direction of the first alignment region 124 and the alignment direction of the second alignment region 126 may not be perpendicular, and may also intersect. Further, the shape, the area, the arrangement, and the number of the first and second transmission regions 62 and 366 may be appropriately changed. For example, in the manner of the first transmission region 62 of FIG. 6, the second transmission region 66 may be formed to extend at least from the right side of the inner side of the first transmission region 62 located at the left end of the paper in the arrangement direction to the right side. The first transmission region 62 at the right end of the paper surface is the left side of the inner side. According to this, the second polarized light spans at least the entire width from the right side of the side of the first transmission area 62 which is the left end of the paper surface in the arrangement direction to the left side of the side of the inner side of the first transmission area 62 which is the right end of the paper surface. The alignment film 120 is irradiated upward.

Although the conveyance of the film 90 is performed simultaneously with the exposure of the first polarized light and the second polarized light in the above embodiment, intermittent exposure for performing transport and exposure, respectively, is also possible. For example, the film 90 may be alternately transported and stopped multiple times in a shorter distance than the length of the first transmission region 62 and the second transmission regions 66, 366 of the mask in the transport direction. The polarizing film and the second polarized light are intermittently exposed to the alignment film 120 through the mask. Further, although the optical film 100 is manufactured using the elongated film 90 in the above embodiment, the optical film 100 may be manufactured one by one using a film having the same length as the optical film 100.

In addition to the embodiment shown in FIG. 9, although the illuminances of the first polarized light and the second polarized light are the same, the illuminance of the first polarized light and the second polarized light may be different. At this time, the exposure amount of the first polarized light irradiated onto the alignment film 120 and the exposure of the second polarized light may be adjusted according to the areas of the first transmission region 62 and the second transmission regions 66 and 366 and the illuminance of the first polarized light and the second polarized light. the amount. Alternatively, the opening lengths of the first transmission region 62 and the second transmission regions 66 and 366 may be made equal, and the exposure amount of the first polarized light irradiated onto the alignment film 120 and the second amount may be adjusted according to the illuminance of the first polarized light and the second polarized light. The amount of exposure of the polarized light.

In the above embodiment, the distance between the first transmission region 62 in the width direction and the first transmission region 62 and the adjacent first transmission region 62 is the same, but may be different. For example, in consideration of the fact that the first polarized light transmitted through the first transmission region 62 is widened, it is preferable that the length of the first transmission region 62 in the arrangement direction is shorter than the length of the first alignment region 124 in the arrangement direction. At this time, the length of the first transmission region 62 in the width direction is shorter than the distance between the first transmission region 62 and the adjacent first transmission region 62.

Although the first transmission region and the second transmission region are disposed at different positions along the transport direction in the above embodiment, they may be formed at the same position. In other words, the first transmission region and the second transmission region may also be continuous in the transport direction. At this time, the first polarized light and the second polarized light are irradiated separately.

An experiment for demonstrating the effects of the above embodiment will be described below. First, a mask for a comparative example for producing an optical film of a comparative example which is compared with the embodiment in this experiment will be described. Figure 12 is a plan view of a mask 938 for a comparative example. As shown in FIG. 12, the mask 938 has a first mask region 982 in which a first transmission region 962 is formed and a second mask region 984 in which a second transmission region 966 is formed. The first mask region 982 is the same as the first mask region 82 of the embodiment. The second mask region 984 has a plurality of second transmission regions 966. The second transmission region 966 has the same shape as the first transmission region 962. In the width direction, the second transmission region 966 is disposed between the first transmission region 962 and the adjacent first transmission region 962. That is, one side of the second transmission region 966 extending in the conveying direction is provided on an extension line of one side of the first transmission region 962 extending in the conveying direction. Two optical films of Comparative Example 1 and Comparative Example 2 were produced using the mask 938 for the comparative example. The optical film 100 of the embodiment is made using the mask 38 shown in FIGS. 6 and 7.

In Comparative Examples 1, 2, and the examples, the alignment film 120 was formed of a photo-alignment resin, and the thickness after drying was 10 nm to 50 nm. In Comparative Examples 1, 2, and the examples, the liquid crystal film 122 was formed of an ultraviolet curable nematic liquid crystal, and the thickness after drying was 1.0 μm to 1.2 μm. In Comparative Examples 1, 2 and the examples, the illuminances of the first polarized light and the second polarized light were both 78 mW/cm ² . The first exposure amount per unit area irradiated in the examples was 27.8 mJ/cm ² , and the second exposure amount per unit area was 9.3 mJ/cm ² . The second exposure amount of the embodiment was adjusted by setting the length of the opening as the second transmission region 66 in the transport direction length to 13.8 mm. The first exposure amount is an integrated value of the illuminance of the first polarized light irradiated to the alignment film 120 during the irradiation time. The second exposure amount is an integrated value of the illuminance of the second polarized light irradiated to the alignment film 120 during the irradiation time.

Photographs were taken in these comparative examples and examples. The photograph was obtained by photographing a specimen in which a comparative example and an example were sandwiched between a linear polarizing plate and a circularly polarizing plate at an magnification of 100 times with an optical microscope.

FIG. 13 is a photograph of Comparative Example 1 in which the first and second unexposed regions are formed on the alignment film 120 in addition to the first alignment region 124 and the second alignment region 126. The reason why the unexposed area is formed is, for example, that the rotation of the mask 938 around the vertical direction perpendicular to the face of the mask 938 causes the first transmission area 962 and the second transmission area 966 to be inclined from the conveying direction, and the film 90 is A sputum occurred during the transportation. FIG. 14 is a photograph of Comparative Example 2 in which almost no unexposed regions were formed on the alignment film 120. Fig. 15 is a photograph of the optical film 100 of Example 8 to be described later.

As can be seen from the photograph shown in Fig. 13, it is possible to form an unexposed area when exposure is performed by the mask 938 for comparison. Further, as shown in FIG. 14, the possibility that the unexposed areas are not formed by the mask 938 for comparison is about 95% or less. On the other hand, as can be seen from the photograph and the manufacturing method shown in FIG. 15, in the present embodiment, the unexposed regions are not formed with almost 100% probability, so that the first alignment regions 124 and the second alignment regions are seamlessly formed. 126. Further, comparing FIG. 14 with FIG. 15, it can be seen that the boundary between the first alignment area and the second alignment area in Comparative Example 2 is rough, and in the embodiment, the first alignment area 124 and the second. The boundary of the alignment area 126 is a substantially straight line.

Then, the liquid crystal alignment degrees of the comparative examples and the examples were examined. Table 1 is a table showing the calculation results of the alignment degrees of the comparative examples and the examples. The degree of alignment of the liquid crystal is a value obtained by calculating the standard deviation of the alignment angle distribution based on the alignment angle data of the first polarization modulation unit 104 and the second polarization modulation unit 106 of a certain area. The smaller the value indicating the degree of alignment, the better the alignment of the liquid crystal, that is, the alignment of the liquid crystal molecules in the alignment direction. In particular, if the degree of alignment is 1 or less, a stereoscopic image can be viewed, and if the degree of alignment is 0.5 or less, there is almost no crosstalk, and a clear stereoscopic image can be viewed. The following measurement was performed using a KOBRA-CCD manufactured by Oji Scientific Instruments Co., Ltd. for the alignment angle of the first polarization modulation unit 104 and the second polarization modulation unit 106 in a predetermined area. First, the optical films of the examples and the comparative examples were cut into a square shape of about 40 mm × about 40 mm as a sample. The sample is then placed on the specimen table of the KOBRA-CCD. The measurement range is set on the range setting screen so that only the area of one of the first polarization modulation unit 104 and the second polarization adjustment unit 106 is measured. Then, the alignment angle of the set measurement range was measured using the measurement wavelength of 590 nm. The standard deviation of the alignment angle distribution was calculated from the alignment angle data of the measurement range obtained after the measurement. Will The standard deviation of the alignment angle distribution is used as the alignment of the liquid crystal. Further, regarding Comparative Example 1, the degree of alignment of the unexposed regions shown in Fig. 13 was also described. In Table 1, the first and second exposure amounts in the steps of manufacturing the respective examples were combined and described.

As shown in Table 1, it can be seen that in Comparative Example 1, the alignment degrees of the first and second unexposed regions were extremely poor. From this, it can be seen that crosstalk between the image for the right eye and the image for the left eye is caused in Comparative Example 1. On the other hand, in any of Examples 1 to 19, the unexposed regions of Comparative Example 1 were not formed. In the alignment degrees of any of Examples 1 to 19, an excellent value which is better than the degree of alignment of the first unexposed region of Comparative Example 1 was exhibited. Also, you can see that in implementation In Examples 1 to 19, except for Examples 5, 11, and 14, the degree of alignment was 1 or less, which was sufficient to allow a stereoscopic image to be seen. Further, in Examples 2 to 4, Examples 7 to 10, Example 13, and Examples 16 to 19, the degree of alignment was 0.5 or less. From this, it can be seen that in the examples 2 to 4, the examples 7 to 10, the example 13 and the examples 16 to 19, a clear stereoscopic image can be seen. Further, in Examples 2 to 4, Examples 7 to 10, Example 13, and Examples 16 to 19, any of the first alignment region 124 and the second alignment region 126 showed a value superior to that of Comparative Example 2. .

Fig. 16 is a graph showing the results of determination of the degree of alignment of Examples 1 to 19. The determination of the degree of alignment is determined based on a large numerical value among the degrees of alignment of the first polarization modulation unit 104 and the second polarization modulation unit 106. "○" depicted in Fig. 16 indicates an embodiment in which the degree of alignment is 0.5 or less. "△" indicates an example in which the degree of alignment is 0.5 or more and 1 or less. "X" indicates an embodiment in which the degree of alignment is greater than 1°.

As shown in FIG. 16, when the optical film 100 is judged based on the degree of alignment, it is preferable to use the regions surrounded by the first embodiment, the fourth embodiment, the eighth embodiment, and the sixth embodiment. This region satisfies the following conditions when X is the first exposure amount [mJ/cm ² ] and Y is the second exposure amount [mJ/cm ² ].

0.281X+1.48≦Y≦1.10X-6.84 27.8≦X≦69.4

Further, when the optical film 100 is determined according to the degree of alignment, it is more preferably a region enclosed in the second embodiment, the fourth embodiment, the eighth embodiment, and the seventh embodiment. This region satisfies the following conditions when X is the first exposure amount [mJ/cm ² ] and Y is the second exposure amount [mJ/cm ² ].

0.281X+1.48≦Y≦0.885X-8.09 27.8≦X≦69.4

Although the embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various changes and modifications can be added to the above embodiments. It is apparent from the description of the scope of the patent application that such modified and improved embodiments are also included in the technical scope of the present invention.

It should be noted that the order of execution of the processes, the procedures, the steps, the stages, and the like in the devices, systems, programs, and methods shown in the claims, the description, and the drawings are as long as "early", " Earlier than "etc., or as long as the previously processed output is not used in later processing, it can be implemented in any order. Regarding the action flow in the scope of application for patent application, the specification and the drawings, the use of "first", "then", etc. for convenience, but It does not mean that it must be implemented in this order.

38‧‧‧ mask

56‧‧‧ mask substrate

58‧‧‧Lighting layer

62‧‧‧First transmission area

66‧‧‧second transmission area

82‧‧‧First mask area

84‧‧‧Second mask area

Claims (10)

A method of producing an optical film, the optical film having an alignment film on which a plurality of first alignment regions aligned in a first alignment direction and a first alignment direction intersecting the first alignment direction are alternately arranged a plurality of second alignment regions in the two alignment directions, the manufacturing method comprising: a first alignment step of: irradiating the alignment film with the first polarized light through the first mask region to form the plurality of first alignment regions, In the first mask region, a plurality of first transmission regions through which the first polarized light is transmitted and a plurality of first light blocking regions that block the first polarized light are alternately arranged in the arrangement direction; and a second alignment step: At least a portion of the plurality of second alignment regions and the first alignment region continuous with the second alignment region in the alignment direction illuminate a second polarization having a polarization direction different from the first polarization to form the plurality of Second alignment area. The method for producing an optical film according to the first aspect of the invention, wherein in the second alignment step, the inner side to the other end of the first transmission region from one end in the arrangement direction At least the second polarized light is irradiated over the entire width of the inner side of the first transmission region. The method for producing an optical film according to claim 1 or 2, further comprising: a transporting step of transporting the alignment film; and performing the first alignment step while performing the transporting step And the second alignment step. The method for producing an optical film according to claim 3, wherein in the second alignment step, the second polarized light is irradiated through the second mask region in which the second transmission region is formed; the second transmission a region extending at least from an inner side of the first transmission region at one end to an inner side of the first transmission region at the other end in the arrangement direction, and is disposed in the transport direction not in the plurality of first a region where the transmission region and the plurality of first light-shielding regions overlap. The method for producing an optical film according to the first aspect of the invention, wherein the exposure amount per unit area of the second polarized light irradiated onto the alignment film is smaller than each of the first polarized light irradiated onto the alignment film Exposure per unit area. The method for producing an optical film according to the first aspect of the invention, wherein the relationship between the exposure amount X per unit area of the first polarized light and the exposure amount Y per unit area of the second polarized light is 0.281×+1.48≦ Y≦1.10X-6.84 27.8≦X≦69.4. The method for producing an optical film according to the first aspect of the invention, wherein the relationship between the exposure amount X per unit area of the first polarized light and the exposure amount Y per unit area of the second polarized light is 0.281×+1.48≦ Y≦0.885X-8.09 27.8≦X≦69.4. The method for producing an optical film according to claim 1, wherein the second polarized light has a smaller illuminance than the first polarized light. A mask comprising: a first mask region in which a plurality of first transmission regions for transmitting a first polarized light and a plurality of first light shielding regions for blocking the first polarized light are alternately arranged in an arrangement direction; and a second mask a mode region formed with a second transmission region that transmits a second polarized light having a polarization direction different from a polarization direction of the first polarization; the second transmission region is from the first transmission region in the arrangement direction a portion extending at least to a portion of the adjacent first transmission region, and formed in a direction perpendicular to the alignment direction not overlapping the plurality of first transmission regions and the plurality of first light shielding regions s position. An apparatus for manufacturing an optical film, comprising: the mask described in claim 9; and a conveying unit configured to convey an alignment film on a side of the mask in a direction intersecting the arrangement direction; a first polarized light output portion for irradiating the first polarized light to the alignment film via the first transmission region; and a second polarized light output portion for irradiating the alignment film through the second transmission region Said second polarized light.