Patterned phase difference plate manufacturing method and patterned phase difference plate

Abstract

To provide a patterned phase difference plate manufacturing method with which it is possible, using a relatively simple technique, to manufacture a patterned phase difference plate having excellent long-range dimensional stability in a phase difference area despite its large area.SOLUTION: A patterned phase difference plate 10 is manufactured according to a method including the steps of applying a liquid crystal alignment agent to form a coating, exposing the coating with light through a photo mask to form an optical alignment film 12, and applying polymerizable liquid crystal onto the optical alignment film 12 for curing to form a liquid crystal layer 13. The liquid crystal alignment agent contains a polymer having a cinnamate structure, an azobenzene structure, or a main chain decomposition type structure. A glass substrate 11 has, on a substrate surface to which the liquid crystal alignment agent is applied, an alignment marker part 19 that is an index for alignment relative to the glass substrate 11. In scan exposure, a relative position of the photo mask to the alignment marker part 19 is detected, and on the basis of a result of the detection, the coating is irradiated with radiation while the relative position of the photo mask to the glass substrate 11 is corrected.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for producing a patterned retardation plate and a patterned retardation plate. [Background technology]

[0002] Liquid crystal displays (LCDs) are widely used in televisions and various monitors. There are various known LCD display modes, such as TN (Twisted Nematic), IPS (In Plane Switching), FFS (Fringe Field Switching), VA (Vertically Aligned), and PSA (Polymer Sustained Alignment). Currently, LCDs using these liquid crystal display mode technologies are being produced.

[0003] Various optical materials are used in liquid crystal displays. One of these materials, a retardation plate (including a retardation film), is used in the manufacture of liquid crystal displays to eliminate coloration of the display and to eliminate viewing angle dependency, which is the change in display color and contrast ratio depending on the viewing angle. Retardation plates are generally manufactured by stretching plastic films. In addition, in order to obtain retardation plates with more complex optical properties, a method of manufacturing a retardation plate by curing a polymerizable liquid crystal has been proposed (see, for example, Patent Document 1).

[0004] In a method for manufacturing a retardation plate by curing a polymerizable liquid crystal, a liquid crystal alignment film is generally provided on the substrate surface in order to align the liquid crystal molecules in a predetermined direction relative to the substrate surface. The liquid crystal alignment film provided on the retardation plate is formed by a photo-alignment method in which a photosensitive thin film such as polyvinyl cinnamate is irradiated with polarized or unpolarized radiation (see, for example, Patent Documents 2 and 3). The photo-alignment method not only achieves uniform liquid crystal alignment, but also has the advantage of being able to arbitrarily form multiple regions with different alignment directions of liquid crystal molecules on a single substrate by using a photomask during radiation irradiation.

[0005] In recent years, various technologies for displaying three-dimensional (3D) images have been investigated. Furthermore, the popularity of 3D games has led to an increasing demand for displays capable of displaying 3D images at home. Furthermore, demand for displays capable of displaying 3D images is also increasing in signage, amusement facilities offering immersive experiences, and other such facilities. One proposed method for displaying such 3D images involves placing a patterned retardation plate having multiple retardation regions in which liquid crystal molecules have different orientations on the front surface of the display, displaying a right-eye image and a left-eye image on the display screen, and viewing the images through polarized glasses with different polarization states for the right and left eyes (see, for example, Patent Document 4). The advantages of this display method include reduced flickering of the stereoscopic images, the need for a single display device, and the ease of use in homes and a wide range of facilities. Furthermore, the stereoscopic images can be easily viewed by the viewer wearing lightweight, inexpensive polarized glasses. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-234146 [Patent Document 2] Japanese Patent Application Laid-Open No. 2004-163646 [Patent Document 3] Japanese Patent Application Laid-Open No. 2002-250924 [Patent Document 4] Patent No. 3461680 Summary of the Invention [Problem to be solved by the invention]

[0007] To enable viewers to perceive high-definition 3D images using polarization technology, it is necessary to precisely pattern the patterned retarder placed in front of the display at the pixel level in order to precisely control the polarization state of the light entering each of the viewer's left and right eyes through polarized glasses. However, it is difficult to achieve high-precision patterning when manufacturing patterned retarder using the photo-alignment method, and this can result in a phenomenon known as "crosstalk," in which the images for the right and left eyes blend together when a viewer wears polarized glasses and watches 3D images, degrading display quality.

[0008] In recent years, for example, liquid crystal displays have grown in size to over 100 inches, and ultra-high-definition video technologies such as 8K resolution are beginning to become widespread. In order to combine such large, high-definition liquid crystal displays with patterned retardation films to produce large, high-definition 3D display devices, it was necessary to pattern a large substrate with an extremely small width, in a linear pattern, while suppressing variations in width, which had been a technical barrier.

[0009] To manufacture a high-definition patterned retarder compatible with high-definition 3D liquid crystal displays, it is conceivable to use a large glass substrate (e.g., a mother substrate) with the same size and surface smoothness as those used in liquid crystal display manufacturing, rather than a film, as the base material, and to obtain a patterned retarder by patterning the large glass substrate. Patterning in a retarder is generally performed by exposing a photosensitive film through a photomask.

[0010] However, when using a large glass substrate with a width exceeding 2 m as the substrate, it is not practical to precisely control the positional relationship between the photomask and the substrate during the photo-alignment process and to uniformly irradiate a large area of ​​photosensitive thin film with radiation in a single exposure process due to limitations on radiation intensity and equipment size. Furthermore, increasing the size of the photomask leads to increased manufacturing costs.

[0011] Furthermore, in order to avoid the limitations of the exposure apparatus, it is conceivable to prepare photomasks of sizes suitable for each size of liquid crystal display for different uses, and perform exposure using an exposure apparatus equipped with a photomask of a size corresponding to the size of the liquid crystal display to manufacture a patterned retardation plate. However, there is a wide range of sizes of liquid crystal displays, and preparing exposure apparatuses equipped with photomasks corresponding to each size would result in high costs and would be impractical.

[0012] In view of this situation, there is a demand for a technology that can manufacture, at a realistic cost, a patterned retardation plate that is large-area, highly accurate, capable of displaying high-definition images, and that has excellent dimensional stability in the length direction of the retardation region (hereinafter also referred to as "long-distance dimensional stability"), assuming application to large liquid crystal displays.

[0013] The present invention has been made in view of the above-mentioned problems, and a main object of the present invention is to provide a method for manufacturing a patterned retardation plate that can manufacture a patterned retardation plate that has a large area but excellent long-distance dimensional stability of the retardation region by a relatively simple method. [Means for solving the problem]

[0014] In order to solve the above problems, the present invention provides the following method for manufacturing a patterned retardation plate and the patterned retardation plate.

[0015] [1] A method for manufacturing a patterned retarder, comprising: a film-forming step of applying a liquid crystal alignment agent onto a glass substrate to form a coating film; an exposure step of using a plurality of exposure units each having a light source and a photomask to irradiate the coating film with radiation from the light source through the photomask to form a photo-alignment film; and a liquid crystal layer-forming step of applying a polymerizable liquid crystal onto the photo-alignment film and curing it to form a liquid crystal layer, wherein the liquid crystal alignment agent contains a polymer having a cinnamate structure, an azobenzene structure, or a main-chain decomposition type structure, and the glass substrate has, on its surface on which the liquid crystal alignment agent is applied, alignment marker portions as indicators for alignment with the glass substrate, and in the exposure step, scanning exposure is performed in which the glass substrate on which the coating film has been formed is moved relatively to the plurality of exposure units in a predetermined movement direction, and radiation is irradiated onto the coating film in regions corresponding to each of the plurality of exposure units, and in the scanning exposure, the relative position of the photomask with respect to the alignment marker portions is detected, and the radiation is irradiated onto the coating film while correcting the relative position of the photomask with respect to the glass substrate based on the detection result.

[0016] [2] In the exposure step, the scanning exposure is performed multiple times by changing the radiation irradiation area of ​​the coating film, thereby obtaining the photo-alignment film having multiple areas in which the alignment orientations of liquid crystal molecules are different from each other. [1] The method for producing a patterned retardation film according to the above [1]. [3] The method for producing a patterned retardation plate according to [2] above, wherein the alignment marker portion is formed of a black matrix material. [4] The method for manufacturing a patterned retardation plate according to [2] or [3] above, wherein the alignment marker portion is arranged at a position overlapping with a boundary portion of each of the plurality of regions when viewed from a direction perpendicular to the substrate surface. [5] The method for producing a patterned retardation plate according to any one of the above [1] to [4], wherein in the exposure step, the radiation is irradiated onto the substrate surface from an oblique direction. [6] A patterned retardation plate comprising: a glass substrate; a photo-alignment film disposed on the glass substrate; a liquid crystal layer disposed on the photo-alignment film and formed by curing a polymerizable liquid crystal; and a black matrix layer, wherein the photo-alignment film contains a polymer having a cinnamate structure, an azobenzene structure, or a main-chain decomposition structure, and has a plurality of regions in which the alignment orientations of the liquid crystal molecules are different from each other; and the black matrix layer is in contact with the substrate surface of the glass substrate and is disposed at a position overlapping with the boundaries of each of the plurality of regions when viewed from a direction perpendicular to the substrate surface. [Effects of the Invention]

[0017] According to the present invention, by performing scanning exposure using multiple exposure units each equipped with a photomask and a light source, it is possible to reduce the size of the photomask and exposure device even when the exposure target area of ​​the photosensitive coating film formed on a large glass substrate is large. Furthermore, according to the present invention, an alignment marker for alignment with the glass substrate is provided on the substrate surface on which the liquid crystal alignment agent is applied. During scanning exposure, the relative position of the photomask with respect to the alignment marker is detected, and based on the detection result, the relative position of the photomask with respect to the glass substrate is corrected while irradiating radiation onto the coating film formed by the liquid crystal alignment agent. This makes it possible to obtain a patterned retardation plate that is large in area but has excellent long-distance dimensional stability of the retardation region. That is, according to the present invention, a high-resolution patterned retardation plate can be obtained by a relatively simple method. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a cross-sectional view illustrating a schematic configuration of a patterned retardation plate according to a first embodiment. [Figure 2] FIG. 1 is a schematic plan view of a patterned retardation plate according to a first embodiment. [Figure 3] 3A to 3C are diagrams illustrating a method for manufacturing the patterned retardation plate according to the first embodiment. [Figure 4] 1 is a schematic diagram of an exposure device and scanning exposure. [Figure 5]FIG. 2 is a schematic diagram of scanning exposure according to the first embodiment. [Figure 6] 5A to 5C are diagrams showing a method of alignment during scanning exposure according to the first embodiment. [Figure 7] 1 shows an example of the exposure mode in the first scan and the second scan, where (a) shows the first scan and (b) shows the second scan. [Figure 8] FIG. 4 is an explanatory diagram of a position correction process according to the first embodiment. [Figure 9] 5A to 5C are diagrams illustrating details of the position correction process according to the first embodiment. [Figure 10] FIG. 10 is a diagram showing another example of the alignment marker portion 19. [Figure 11] FIG. 10 is a cross-sectional view showing a schematic configuration of a patterned retardation plate according to a second embodiment. [Figure 12] FIG. 10 is a schematic plan view of a patterned retardation plate according to a second embodiment. [Figure 13] FIG. 10 is an explanatory diagram of a position correction process according to the second embodiment. [Figure 14] 10A to 10C are diagrams illustrating details of a position correction process according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, embodiments will be described with reference to the drawings. The manufacturing method of the present disclosure relates to a method for manufacturing a patterned retarder. The patterned retarder obtained by the manufacturing method of the present disclosure can convert linearly polarized light emitted from a liquid crystal display into left- and right-handed circularly polarized light. When placed in front of a liquid crystal display, such a patterned retarder can separate right-eye and left-eye images and deliver them to the viewer, making it suitable as an optical component for a three-dimensional (3D) liquid crystal display. Note that in the following embodiments, identical or equivalent parts are designated by the same reference numerals in the drawings, and the explanations of the parts with the same reference numerals are incorporated herein by reference.

[0020] First Embodiment <Configuration of patterned retardation plate> First, the configuration of a patterned retardation plate manufactured by the manufacturing method of the present disclosure will be described below. As shown in Fig. 1, a patterned retardation plate 10 includes a glass substrate 11, a photo-alignment film 12, and a liquid crystal layer 13, which are laminated in this order. In the following description, the longitudinal direction of the patterned retardation plate 10 is referred to as the X direction, and the direction perpendicular to the longitudinal direction of the patterned retardation plate 10 is referred to as the Y direction. The Y direction is the width direction of the patterned retardation plate 10.

[0021] The glass substrate 11 is formed of, for example, alkali-free glass, quartz glass, float glass, soda glass, Pyrex (registered trademark) glass, or pyrol glass. The thickness of the glass substrate 11 is, for example, 1 to 10 μm. The photo-alignment film 12 is a vertical or horizontal alignment type liquid crystal alignment film, and is provided on one substrate surface of the glass substrate 11. The photo-alignment film 12 is preferably a horizontal alignment film. The photo-alignment film 12 is formed using a liquid crystal alignment agent containing a polymer having a cinnamate structure, an azobenzene structure, or a main-chain decomposition type structure (hereinafter also referred to as a "photo-alignable polymer").

[0022] Photoalignable polymers impart optical anisotropy to coating films formed using liquid crystal alignment agents by causing dimerization, photoisomerization, or photodecomposition of the photoalignable groups (cinnamate structure, azobenzene structure, or main chain decomposition type structure) upon irradiation with radiation. Examples of main chain decomposition type structures include cyclobutane ring structures.

[0023] The main skeleton of the photoalignable polymer is not particularly limited, and examples thereof include polyamic acid, polyamic acid ester, polyimide, addition polymer, polyorganosiloxane, etc. Examples of addition polymers include (meth)acrylic polymers, styrene polymers, maleimide polymers, (meth)acrylic-styrene copolymers, (meth)acrylic-maleimide copolymers, (meth)acrylic-styrene-maleimide copolymers, and styrene-maleimide copolymers. The photoalignable polymer may have a photoalignable group in the main chain of the polymer, in the side chain, or in both the main chain and the side chain of the polymer.

[0024] In this specification, the term "radiation" includes electron beams (visible light, ultraviolet light, far ultraviolet light, extreme ultraviolet light (EUV), etc.) and electromagnetic waves (X-rays, gamma rays, etc.). "(Meth)acrylic" includes "acrylic" and "methacrylic".

[0025] A liquid crystal aligning agent is typically a liquid composition in which a polymer component is dissolved or dispersed in one or more solvents. The liquid crystal aligning agent may contain a photoalignable polymer alone as the polymer component, or may contain a polymer without a photoalignable group (hereinafter also referred to as "other polymer") together with the photoalignable polymer. The main skeleton of the other polymer is not particularly limited, and examples thereof include polyamic acid, polyamic acid ester, polyimide, addition polymer, polyorganosiloxane, etc. Among these, at least one other polymer selected from the group consisting of polyamic acid and polyimide is preferred, since it can provide a photoalignment film with excellent liquid crystal alignment properties, heat resistance, and reliability. In addition to the polymer component and solvent, the liquid crystal aligning agent may further contain one or more additives such as a crosslinking agent, an adhesion aid, an ultraviolet absorber, and a photosensitizer.

[0026] The liquid crystal layer 13 is a layer that has the function of rotating the electric field of incident light as it propagates, converting linearly polarized light into circularly polarized light, and is provided adjacent to the photo-alignment film 12 on the opposite side of the photo-alignment film 12 from the glass substrate 11. The liquid crystal layer 13 is formed by applying and curing a polymerizable liquid crystal onto the photo-alignment film 12. The orientation direction of the liquid crystal molecules of the polymerizable liquid crystal applied onto the photo-alignment film 12 is regulated by the photo-alignment film 12.

[0027] The liquid crystal layer 13 has a plurality of retardation regions in which the rotation directions of the electric fields seen from the light propagation direction are different from each other. Specifically, the liquid crystal layer 13 has first retardation regions 14 that generate clockwise circularly polarized light and second retardation regions 15 that generate counterclockwise circularly polarized light (see FIG. 2). The first retardation regions 14 and the second retardation regions 15 each have a stripe shape extending in the X direction, and these retardation regions 14, 15 are arranged alternately at a constant pitch in the Y direction.

[0028] When the patterned retarder 10 is placed in front of a liquid crystal display, linearly polarized image light from, for example, odd-numbered columns of pixels arranged in a matrix on the liquid crystal display is incident on the first retardation region 14, and linearly polarized image light from even-numbered columns is incident on the second retardation region 15. The linearly polarized light incident on each of the first retardation region 14 and the second retardation region 15 is converted into right-handed circularly polarized light and emitted from the first retardation region 14, and converted into left-handed circularly polarized light and emitted from the second retardation region 15. When a viewer wears circularly polarized glasses with polarized light whose polarization directions are different, the right eye perceives only the image of one pixel column, and the left eye perceives only the image of the other pixel column. This allows the viewer to view a 3D image.

[0029] The liquid crystal layer 13 only needs to have a function of making the light beams passing through the first retardation region 14 and the second retardation region 15 have a phase difference of λ / 2 wavelength, and the light emitted from the liquid crystal layer 13 is not limited to circularly polarized light, but may also be linearly polarized light. In this specification, circularly polarized light is not limited to perfectly circularly polarized light, but may also be elliptically polarized light.

[0030] A black matrix layer 16 is disposed at the boundary between the first retardation region 14 and the second retardation region 15. The black matrix layer 16 is formed by, for example, a lithography method using a coloring composition containing a black colorant (carbon black or the like).

[0031] The black matrix layer 16 has a linear shape extending from one end to the other end in the X direction of the glass substrate 11, and is provided at the boundary between the first retardation region 14 and the second retardation region 15, straddling the first retardation region 14 and the second retardation region 15. Note that, although black matrix layers 16 are provided at all boundaries between the retardation regions 14 and 15 in the patterned retardation plate 10, they are not shown in Fig. 2. The black matrix layers 16 are arranged in stripes at a constant pitch, and are therefore also called black stripes.

[0032] The black matrix layer 16 covers a portion of each of the first retardation region 14 and the second retardation region 15. The width of the black matrix layer 16 (i.e., the length in the Y direction) is preferably 50% or less of the width of each of the retardation regions 14, 15. When viewed from a direction perpendicular to the substrate surface of the glass substrate 11, the center line of the black matrix layer 16 extending in the X direction preferably overlaps the boundary line between the first retardation region 14 and the second retardation region 15. The provision of such a black matrix layer 16 in the patterned retardation plate 10 can suppress the occurrence of crosstalk, in which images for the right eye and left eye are mixed together, when a viewer uses polarized glasses to view a liquid crystal display in front of which the patterned retardation plate 10 is arranged.

[0033] 1 and 2, the glass substrate 11 has a display-corresponding region 17 and a non-display-corresponding region 18 on the substrate surface to which the liquid crystal alignment agent is applied. The display-corresponding region 17 is a region that faces the display region of the liquid crystal display when the patterned retarder 10 is placed in front of the liquid crystal display. The display-corresponding region 17 is also an alignment film formation region where a liquid crystal alignment agent is applied and exposed to light to form a photo-alignment film 12.

[0034] The non-display corresponding regions 18 are regions of the entire substrate surface to which the liquid crystal alignment agent is applied, excluding the display corresponding regions 17. The non-display corresponding regions 18 are provided at both ends in the Y direction (the width direction of the glass substrate 11) of the entire substrate surface to which the liquid crystal alignment agent is applied. Each of the two non-display corresponding regions 18 is provided with an alignment marker portion 19. The alignment marker portions 19 are indicators for aligning a member separate from the glass substrate 11 with the glass substrate 11.

[0035] 1 and 2, the alignment marker portion 19 is a narrow layer disposed on the substrate surface of the glass substrate 11, and extends in the X direction a predetermined length inward from the outer edge of the glass substrate 11 in the Y direction. The width (length in the Y direction) of the alignment marker portion 19 is, for example, 1 to 5 μm, and the height is, for example, 50 to 500 nm. The constituent material of the alignment marker portion 19 is not particularly limited, and examples thereof include resin, transparent electrode material, inorganic film material, and metal. In this embodiment, the alignment marker portion 19 is formed from a black matrix material (i.e., a light-shielding material). In this case, when providing the alignment marker portion 19, the device and material for forming the black matrix layer 16 can be used, and new functions can be easily imparted.

[0036] The alignment marker portions 19 are not limited to structures that extend continuously from one end to the other end of the glass substrate 11 in the X direction, as shown in FIG. 2 . The alignment marker portions 19 may be, for example, recesses formed on the substrate surface using a laser. The alignment marker portions 19 may also be structures that are arranged discontinuously from one end to the other end of the glass substrate 11 in the X direction. Furthermore, the alignment marker portions 19 may be formed by arranging a pattern of a predetermined shape (for example, a circular, rectangular, cross-shaped, or other mark) continuously or discontinuously from one end to the other end of the glass substrate 11 in the X direction.

[0037] The patterned retardation film 10 may further include a different configuration in addition to the glass substrate 11, the photo-alignment film 12, the liquid crystal layer 13, and the black matrix layer 16. For example, the patterned retardation film 10 may include an anti-reflection film on the surface of the glass substrate 11 opposite to the photo-alignment film 12 across the glass substrate 11.

[0038] <Method of manufacturing a patterned retardation plate> Next, we will explain the method for manufacturing the patterned retardation plate 10. The patterned retardation plate 10 is manufactured by a method including the following film formation step, exposure step, and liquid crystal layer formation step. Film formation process: A process of applying a liquid crystal alignment agent onto a glass substrate 11 to form a coating film 12A. Exposure step: A step of irradiating the coating film 12A formed by the liquid crystal alignment agent with radiation to form the photo-alignment film 12. Liquid crystal layer forming step: A step of forming the liquid crystal layer 13 by applying a polymerizable liquid crystal onto the photo-alignment film 12 and curing it. Each step will be described in detail below with reference to FIG. 3 as needed.

[0039] (film formation process) In the film formation step, a liquid crystal alignment agent is applied onto a glass substrate 11 to form a coating film 12A. As shown in FIG. 3(a), a substrate is used as the glass substrate 11, on which alignment marker portions 19 are previously provided in non-display corresponding regions 18 at both ends of the glass substrate 11 in the Y direction. The method for forming the alignment marker portions 19 is not particularly limited. For example, the alignment marker portions 19 are formed on the surface of the glass substrate 11 by a known photolithography technique. A specific example of a method for forming the alignment marker portions 19 by a photolithography technique is a method in which a black matrix material (for example, a coloring composition containing a black colorant, a binder resin, and a solvent) is applied to the non-display corresponding regions 18 of the glass substrate 11, radiation is applied through a photomask, and then a development process is performed.

[0040] The liquid crystal alignment agent is applied to the entire surface of the display corresponding area 17, which is the portion of the surface of the glass substrate 11 excluding the non-display corresponding area 18. The method for applying the liquid crystal alignment agent is not particularly limited, and can be performed by a known application method such as a roll coater method, a spinner method, an offset printing method, a flexographic printing method, or an inkjet method.

[0041] After the liquid crystal aligning agent is applied, preliminary heating (pre-baking) is preferably carried out for the purpose of preventing dripping of the applied liquid crystal aligning agent. The pre-baking temperature is preferably 30 to 120°C, and the pre-baking time is preferably 0.1 to 10 minutes. Thereafter, a baking treatment (post-baking) is carried out for the purpose of removing the solvent in the applied liquid crystal aligning agent. The baking temperature (post-baking temperature) at this time is preferably 80 to 300°C, more preferably 100 to 250°C. The post-baking time is preferably 1 to 200 minutes, more preferably 5 to 100 minutes. The thickness of the coating film after post-baking is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm.

[0042] When applying the liquid crystal alignment agent to the glass substrate 11, a functional silane compound, titanate, etc. may be applied to the glass substrate 11 in advance to further improve the adhesion between the substrate surface and the coating film 12A.

[0043] (Exposure process) In the subsequent exposure step, the coating film 12A formed in the display-corresponding region 17 of the glass substrate 11 is subjected to a photo-alignment treatment (see FIG. 3(b)), thereby imparting liquid crystal alignment ability to the coating film 12A, thereby obtaining a photo-alignment film 12. In the photo-alignment treatment, polarized ultraviolet light and visible light having a wavelength of 150 to 800 nm can be used as the radiation irradiated onto the coating film 12A. The radiation irradiated onto the coating film 12A is preferably polarized ultraviolet light having a wavelength of 200 to 400 nm. For example, when a liquid crystal alignment agent containing a polymer having a cinnamate structure as the photo-alignable polymer is used to form the photo-alignment film 12, polarized ultraviolet light having a wavelength of 313 nm can be used. Furthermore, when a liquid crystal alignment agent containing a polymer having an azobenzene structure is used, polarized ultraviolet light having a wavelength of 365 nm can be used, and when a liquid crystal alignment agent containing a polymer having a cyclobutane ring structure is used, polarized ultraviolet light having a wavelength of 254 nm can be used. In terms of high sensitivity, the photoalignable polymer is preferably a polymer having a cinnamate structure or an azobenzene structure.

[0044] The radiation irradiated onto the coating film 12A may be linearly polarized or partially polarized. When the radiation used is linearly polarized or partially polarized, the radiation may be irradiated from a direction perpendicular to the substrate surface, from an oblique direction, or a combination of these. In order to reduce the height of the exposure device including the light source and to suppress the "stray light phenomenon" in which polarized light reflected from the substrate is reflected again by a photomask or the like and irradiated onto unintended locations on the substrate, the exposure of the coating film 12A is preferably performed from an oblique direction. When irradiating the coating film 12A with radiation from an oblique direction, the irradiation angle is, for example, 10 to 60 degrees.

[0045] Examples of light sources that can be used include low-pressure mercury lamps, high-pressure mercury lamps, deuterium lamps, metal halide lamps, argon resonance lamps, xenon lamps, excimer lasers, and mercury-xenon lamps (Hg—Xe lamps).

[0046] The radiation dose to the coating film 12A is 1 to 10,000 J / m 2It is preferable to set the value to 10 to 3,000 J / m 2 When a liquid crystal aligning agent containing a polymer having a cinnamate structure or a polymer having an azobenzene structure is used as the photo-alignment polymer, the radiation dose to the coating film 12A is preferably 10 to 1,000 J / m 2 By applying such a relatively small irradiation dose, the processing speed of the exposure apparatus 20 can be improved, and large substrates can be processed practically. After the light irradiation for imparting alignment ability, the substrate surface may be washed with, for example, water, an organic solvent (e.g., methanol, isopropyl alcohol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, etc.) or a mixture thereof, or the substrate may be heated.

[0047] In this exposure step, radiation is irradiated to each of the retardation regions 14, 15 to obtain a retardation plate having a plurality of retardation regions 14, 15 with different polarization orientations. Specifically, the photo-alignment treatment is performed by scanning exposure in which radiation with different polarization orientations is irradiated to different regions of the coating film 12A via a photomask 21 arranged between the glass substrate 11 and the light source 22 while the glass substrate 11 on which the coating film 12A is formed is moved relatively in a predetermined moving direction (hereinafter also referred to as "scanning direction W") with respect to the light source 22. Details of the scanning exposure will be described later.

[0048] (Liquid crystal layer formation process) In the liquid crystal layer formation process, a polymerizable liquid crystal is applied to the photo-alignment film 12 and cured to form a liquid crystal layer 13 (see FIG. 3(c)). The polymerizable liquid crystal can be applied by a known application method, such as a roll coater method, a spinner method, an offset printing method, a flexographic printing method, or an inkjet method, similar to the method used to apply the liquid crystal alignment agent. The solvent contained in the polymerizable liquid crystal is then removed by a heating treatment, an irradiation treatment with unpolarized radiation, or a combination thereof, and the polymerizable liquid crystal is cured to form the liquid crystal layer 13. The curing treatment of the polymerizable liquid crystal can be performed under conditions appropriately selected depending on the polymerizable group and initiator of the polymerizable liquid crystal used. For example, the curing treatment of the polymerizable liquid crystal may be performed in the air or in an inert gas atmosphere such as nitrogen.

[0049] The polymerizable liquid crystal is not particularly limited as long as it has liquid crystallinity and can be polymerized by heating or irradiation. The polymerizable liquid crystal may be, for example, a nematic liquid crystal compound such as those described in "UV Curable Liquid Crystals and Their Applications" (Liquid Crystals, Vol. 3, No. 1, 1999, pp. 34-42), used alone, or a mixture of multiple compounds. These polymerizable liquid crystal compounds and mixtures thereof can be dissolved in an appropriate solvent for use. Furthermore, by adding an additive such as a chiral agent to the polymerizable liquid crystal compound or mixtures thereof, liquid crystals that exhibit twisted nematic alignment in a direction perpendicular to the substrate surface, cholesteric liquid crystals, or discotic liquid crystals may be used as the polymerizable liquid crystal.

[0050] The thickness of the liquid crystal layer 13 is appropriately selected to obtain the desired optical characteristics. For example, when manufacturing a half-wave plate for visible light with a wavelength of 540 nm, a thickness is selected so that the retardation of the patterned retarder 10 is 240 to 300 nm. Similarly, when manufacturing a quarter-wave plate for visible light with a wavelength of 540 nm, a thickness is selected so that the retardation of the patterned retarder 10 is 120 to 150 nm. The thickness that obtains the desired retardation varies depending on the optical characteristics of the polymerizable liquid crystal used. For example, when using Merck's polymerizable liquid crystal "RMS03-013C," the thickness for manufacturing a quarter-wave plate is selected to be in the range of 0.6 to 1.5 μm.

[0051] When the polymerizable liquid crystal is cured by heating, the heating temperature may be appropriately set to a temperature at which good anisotropy is exhibited. For example, when using Merck's polymerizable liquid crystal "RMS03-013C," the curing treatment may be carried out at a temperature range of 40 to 80°C. When the polymerizable liquid crystal is cured by irradiating it with non-polarized radiation, the radiation dose may be 1,000 to 100,000 J / m. 2 is preferred, and 10,000 to 50,000 J / m 2 is more preferred.

[0052] Thereafter, a striped black matrix layer 16 is formed so as to cover the boundary between the first retardation region 14 and the second retardation region 15 (FIG. 3(d)). The black matrix layer 16 is formed on the surface of the liquid crystal layer 13 by, for example, a known photolithography technique. In this way, the patterned retardation plate 10 shown in FIG. 1 is obtained.

[0053] (scan exposure) Next, the scanning exposure performed in the exposure step will be described in detail. In the exposure step for obtaining the patterned retardation plate 10, it is preferable to perform multiple exposures on the coating film 12A formed from a liquid crystal alignment agent while changing the radiation irradiation region, thereby obtaining a photo-alignment film 12 having multiple regions with different alignment orientations of liquid crystal molecules (hereinafter also referred to as "alignment regions"). When obtaining a patterned retardation plate for a 3D liquid crystal display, it is preferable to perform multiple exposures on the coating film 12A while changing the radiation irradiation region, so that stripe-shaped first alignment regions R1 corresponding to the first retardation region 14 and stripe-shaped second alignment regions R2 corresponding to the second retardation region 15 are alternately formed at a constant pitch in the Y direction.

[0054] An example of the exposure device 20 and scanning exposure used in this embodiment will be described with reference to Fig. 4. In Fig. 4, the arrow with the symbol W indicates the movement direction (scanning direction) of the glass substrate 11 relative to the light source 22, and the arrow with the symbol M indicates the transmission axis direction of the polarizer 23. The scanning direction W corresponds to the "predetermined movement direction."

[0055] The exposure device 20 includes a plurality of exposure units 26 and a scanning unit 24. Each of the plurality of exposure units 26 includes a light source 22 and a photomask 21. In the exposure unit 26, the photomask 21 is disposed above the glass substrate 11 at a predetermined distance (proximity gap), and the light source 22 is disposed above the photomask 21. The photomask 21 has a plurality of slits 25. For convenience, only one slit 25 of the photomask 21 is shown in FIG. 4. The scanning unit 24 has a mechanism for moving the glass substrate 11, on which the coating film 12A has been formed, relative to the exposure unit 26.

[0056] In the exposure device 20, the glass substrate 11 is moved in a scanning direction W relative to the exposure unit 26 by the scanning unit 24, while the light source 22 irradiates the coating film 12A with radiation (specifically, linearly polarized light), thereby scanning and exposing the coating film 12A through the photomask 21. The irradiated light U from the light source 22 passes through the polarizer 23, and the transmitted light oscillating in the direction of the transmission axis passes through the slits 25 in the photomask 21 and is obliquely irradiated onto the coating film 12A formed on the glass substrate 11. By exposing the coating film 12A, the exposed region of the coating film 12A is irradiated with linearly polarized light having a polarization direction corresponding to the transmission axis of the polarizer 23, and the polarization imparts a predetermined orientation. In FIG. 4, the arrows shown on the coating film 12A indicate the polarization direction of the linearly polarized light projected onto the glass substrate 11 (the same applies to FIG. 7). Note that instead of a configuration in which the scanning unit 24 moves the glass substrate 11 relative to the exposure unit 26, a configuration in which the exposure unit 26 moves relative to the glass substrate 11 may be employed.

[0057] Here, in the manufacturing process of the patterned retarder 10, exposure may be performed on the coating film 12A formed on a large (e.g., G8 size or G10 size) mother substrate in order to produce a patterned retarder that can be mounted on a large-screen LCD display or to increase productivity of the patterned retarder by cutting out multiple smaller retarders from a large retarder. It is not realistic to expose such a large glass substrate in a single exposure using a large exposure device or a large photomask large enough to cover the entire area of ​​the coating film 12A in terms of equipment and cost. Even if it were possible to expose the entire area of ​​the coating film 12A in a single exposure, there is a concern that the increased size of the photomask and light source may cause variations in the exposure amount in the width direction of the coating film 12A. Furthermore, there is also concern that misalignment of the photomask relative to the glass substrate 11 (particularly in the width direction) during scanning exposure may cause a decrease in the longitudinal dimensional stability (i.e., long-distance dimensional stability) of each retarder region 14, 15 in the resulting patterned retarder 10.

[0058] Therefore, in this embodiment, a plurality of small exposure units (photomasks and light sources) are used relative to the size of the substrate surface of the glass substrate 11, and radiation is irradiated onto the coating film 12A through the plurality of photomasks per scan for imparting liquid crystal alignment ability to the coating film 12A. This makes it possible to minimize the size of one photomask and the radiation exposure area exposed through one photomask, thereby suppressing an increase in the size of the device and variations in exposure.

[0059] The exposure unit 26 provided in the exposure tool 20 will be described in detail. The exposure tool 20 includes a plurality of light sources 22 and a plurality of photomasks 21. Each light source (first light source 22a, second light source 22b, third light source 22c) is integrated with a corresponding photomask (first photomask 21a, second photomask 21b, third photomask 21c). This results in a plurality of (here, three) exposure units 26 being configured in the exposure tool 20. More specifically, the first photomask 21a is integrated with the first light source 22a to configure a first exposure unit 26a. Similarly, the second photomask 21b is integrated with the second light source 22b to configure a second exposure unit 26b, and the third photomask 21c is integrated with the third light source 22c to configure a third exposure unit 26c. During scanning exposure, the first to third exposure units 26a, 26b, and 26c are moved together as an exposure unit group EG relative to the glass substrate 11 in the scanning direction W (see FIG. 6). The exposure units 26 may be configured to be movable in a direction perpendicular to the scanning direction W (i.e., the width direction), thereby allowing fine adjustment of the position in the width direction relative to the glass substrate 11.

[0060] The arrangement of the multiple photomasks provided in the exposure tool 20 will be described with reference to FIGS. 3, 5, and 6 as appropriate. The photomasks 21 are arranged in a direction perpendicular to the scanning direction W (i.e., the Y direction). In detail, the photomasks 21 include a first photomask 21a and a third photomask 21c arranged on the same line extending in the Y direction, and a second photomask 21b arranged in front of the first photomask 21a and the third photomask 21c as viewed in the scanning direction W and between the first photomask 21a and the third photomask 21c as viewed in the direction perpendicular to the scanning direction W (see FIGS. 3(b) and 5). The ends of the first photomask 21a and the second photomask 21b, and the ends of the third photomask 21c and the second photomask 21b, are arranged to overlap as viewed in the scanning direction W (see FIG. 5).

[0061] During exposure, the glass substrate 11 is moved linearly in the scanning direction W relative to the exposure unit 26, and a single relative movement of the glass substrate 11 relative to the exposure unit 26 exposes the coating film 12A from one end of the glass substrate 11 to the other in the scanning direction W (i.e., the X direction). Therefore, even in cases where the display-corresponding area 17 on the glass substrate 11 is wide and exposure using a single photomask is difficult, such as in the case of a large mother substrate with a side length of more than 2 m, scanning exposure can be performed while avoiding equipment and cost constraints. Furthermore, because the substrate on which the coating film 12A to be exposed is provided is the glass substrate 11, there are advantages such as high surface flatness and dimensional stability, and ease of transport during scanning exposure.

[0062] As the glass substrate 11 is moved in the scanning direction W relative to the exposure unit 26, the coating film 12A on the glass substrate 11 has a non-overlapping region V1, which is exposed once via the first photomask 21a, the second photomask 21b, or the third photomask 21c, and an overlapping region V2, which is exposed twice via the first photomask 21a and the second photomask 21b, or the third photomask 21c and the second photomask 21b, as shown in FIG. 5. The overlapping region V2 is irradiated with radiation through the joint between the first photomask 21a and the second photomask 21b, or the joint between the third photomask 21c and the second photomask 21b. The opening area of ​​the slits 25b in the first photomask 21a, the second photomask 21b, and the third photomask 21c is smaller than the opening area of ​​the slits 25a in the non-overlapping region V1. For example, as shown in FIG. 6, the opening area of ​​the slits 25b arranged in the overlap region V2 becomes smaller toward the end of the photomask 21.

[0063] 6 (1, 2, 3, 4, etc.) represent the column numbers of the pixels constituting the liquid crystal display. For example, odd-numbered columns indicate the first retardation regions 14, and even-numbered columns indicate the second retardation regions 15.

[0064] In order to obtain a patterned retarder 10 having two retardation regions 14, 15 in which the orientation orientation of liquid crystal molecules is different and the electric field rotation direction as viewed from the light propagation direction is different, multiple exposures are performed in the exposure process. Specifically, first, the slits 25 of the photomask 21 are aligned with the regions of the coating film 12A corresponding to the retardation regions 14, 15. Next, while moving the glass substrate 11 in the X direction, polarized ultraviolet light is irradiated obliquely onto the substrate surface through the photomask 21 (first scan). This first scan imparts liquid crystal alignment ability to the region corresponding to one of the two retardation regions 14, 15. At this time, the overlap region V2 is exposed to light through the first photomask 21a and the second photomask 21b, or through the second photomask 21b and the third photomask 21c, in a superimposed manner. The total amount of exposure to the overlap region V2 may be equal to the amount of exposure to the non-overlap region V1, or may be less than the amount of exposure to the non-overlap region V1.

[0065] Next, the unexposed regions of the coating film 12A after the first scan are aligned with the slits 25 of the photomask 21. Then, as in the first scan, the glass substrate 11 is moved in the X direction, and polarized ultraviolet light is irradiated obliquely onto the substrate surface through the photomask 21 (second scan). In the second scan, radiation is irradiated onto the coating film 12A so that the polarization direction of the radiation irradiated onto the coating film 12A differs from that in the first scan. FIG. 7 shows an example of the exposure mode in the first and second scans. FIG. 7 illustrates a case where scan exposure is performed such that the polarization direction of the linearly polarized light irradiated onto the coating film 12A differs by 90 degrees within the substrate plane in the first scan (FIG. 7(a)) and the second scan (FIG. 7(b)). In this way, a photo-alignment film 12 is formed on the glass substrate 11, in which stripe-shaped first alignment regions R1 and second alignment regions R2 extending in the X direction are alternately arranged in the Y direction.

[0066] When the exposure device 20 is relatively small compared to the substrate surface of the glass substrate 11, the first scan and the second scan are each performed multiple times, thereby performing the photo-alignment treatment on the entire coating film 12A by the exposure device 20. For example, in Fig. 5, the coating film 12A is divided into two regions in the X direction, and the first scan and the second scan are performed on one region S1, and then the first scan and the second scan are performed on the other region S2.

[0067] Although the case where the same exposure unit is used for the first scan and the second scan has been described, scanning exposure may also be performed by providing an exposure unit group for the first scan (first exposure unit group) and an exposure unit group for the second scan (second exposure unit group) in the exposure device.

[0068] (Operation of exposure device) Next, the operation of the exposure apparatus 20 configured as described above will be described with reference to FIGS. 5 to 9. The exposure apparatus 20 includes a control unit 40 that carries out a process of transporting the glass substrate 11 and a process of correcting the positional relationship between the glass substrate 11 and the photomask 21. In the scanning exposure for obtaining the patterned retardation plate 10, the control unit 40 detects the relative position Ra of the photomask 21 with respect to the alignment marker portions 19 (S11 in FIG. 8), and performs a process of irradiating the coating film 12A with radiation while correcting the relative position of the photomask 21 with respect to the glass substrate 11 based on the detection result (position correction process). Specifically, the control unit 40 calculates a movement amount ΔR by which the photomask 21 is moved in the width direction based on the relative position Ra detected in S11 (S12 in FIG. 8), and corrects the position of the photomask 21 in the width direction based on the calculated movement amount ΔR (S13 in FIG. 8). During scanning exposure, the above-described position correction process is performed at predetermined time intervals, thereby constantly aligning the glass substrate 11 with the photomask 21 while the glass substrate 11 is being transported.

[0069] There is no particular limitation on the method for detecting the relative position Ra of the photomask 21 with respect to the alignment marker portion 19. As an example, as shown in FIG. 6, the exposure tool 20 is provided with a sensor unit 41 that detects position information of the photomask 21. The control unit 40 inputs detection data from the sensor unit 41 and detects the position of the outer edge of the first photomask 21a with respect to the alignment marker portion 19 as the relative position Ra. Then, the photomask 21 is moved with respect to the glass substrate 11 according to the magnitude of the detected relative position Ra (i.e., the amount of misalignment). The sensor unit 41 is, for example, a camera (imaging means).

[0070] For example, as shown in FIG. 9(a), when it is detected that the outer edge Ta of the first photomask 21a is shifted inward by θ1 in the width direction relative to the alignment marker portion 19, the photomask 21 (and thus the exposure unit 26) is moved outward by θ1 in the width direction based on detection data (e.g., image data) input from the sensor unit 41 (see FIG. 9(b)). This aligns the glass substrate 11 with the photomask 21, and the positional relationship (particularly the positional relationship in the width direction) between the region to be exposed of the coating film 12A and the photomask 21 is highly controlled at all times during scan exposure. As a result, in the liquid crystal layer 13 formed by applying the polymerizable liquid crystal, the linearity of the boundaries of each retardation region 14, 15 and the dimensional stability of the width of each region are ensured from one end to the other end of the coating film 12A in the X direction.

[0071] When detecting the relative position Ra of the photomask 21 with respect to the alignment marker portion 19, instead of a configuration that detects the amount of widthwise deviation at the outer edge portion Ta of the first photomask 21a with respect to the alignment marker portion 19, for example, as shown in Figure 10, an alignment mark 43 (e.g., a linear or cross-shaped mark) may be attached to the edge of the first photomask 21a, and the amount of widthwise deviation between the alignment marker portion 19 and the alignment mark 43 may be detected.

[0072] When correcting the widthwise position of the photomask 21 relative to the glass substrate 11 based on the movement amount ΔR, the glass substrate 11 may be moved in the widthwise direction instead of moving the exposure unit 26 in the widthwise direction.

[0073] According to the first embodiment described above in detail, the scanning exposure for obtaining the patterned retardation plate 10 is configured to use the glass substrate 11 on which the alignment marker portions 19 are formed, detect the relative position Ra of the photomask 21 with respect to the alignment marker portions 19, and perform a process of irradiating the coating film 12A with radiation while correcting the relative position of the photomask 21 with respect to the glass substrate 11 based on the detection result. By forming the liquid crystal layer 13 on the photo-alignment film 12 obtained in this manner, it is possible to manufacture the patterned retardation plate 10 having excellent long-distance dimensional stability of the retardation regions 14, 15 by a relatively simple method, even when a large substrate is used.

[0074] Furthermore, since the alignment marker portion 19 is provided in the non-display corresponding region 18 of the glass substrate 11, it is possible to obtain a large-area patterned retardation plate 10 having excellent long-distance dimensional stability of each of the retardation regions 14 and 15 while adopting a conventional configuration for the black matrix layer 16 and the like.

[0075] Second Embodiment Next, a second embodiment will be described. The second embodiment differs from the first embodiment in that a black matrix layer for suppressing crosstalk is formed on the glass substrate 11 before the coating film 12A is formed, and the black matrix layer functions as an alignment marker portion 19. In the following explanation, the same configuration as the first embodiment will be omitted, and the differences from the first embodiment will be mainly described.

[0076] <Configuration of patterned retardation plate> As shown in FIG. 11 , the patterned retardation plate 100 includes a glass substrate 11, a photo-alignment film 12, a liquid crystal layer 13, and a black matrix layer 116. The black matrix layer 116 is disposed on the surface 11A of the glass substrate 11 where the photo-alignment film 12 is formed, at a position overlapping with the boundary between the two retardation regions 14 and 15 when viewed from a direction perpendicular to the formation surface 11A (see FIGS. 11 and 12 ). Note that the patterned retardation plate 100 also has a black matrix layer 116 at all the boundary between the retardation regions 14 and 15, but this is omitted in FIG. 12 . The glass substrate 11 may or may not have a non-display corresponding region 18 together with a display corresponding region 17 on the substrate surface (i.e., the formation surface 11A) where the liquid crystal alignment agent is applied. When the black matrix layer 116 is used as the alignment marker portion 19, it is not necessary to provide the non-display corresponding area 18 on the glass substrate 11, and the display corresponding area 17 can be secured as wide as possible.

[0077] <Method of manufacturing a patterned retardation plate> Next, the operation of the exposure apparatus 20 will be described with reference to Fig. 13. In this embodiment, in the scanning exposure for obtaining the patterned retardation plate 100, the glass substrate 11 on which the black matrix layer 116 and the coating film 12A are formed is used as the exposure target. The control unit 40 detects the relative position Rb of the photomask 21 with respect to the black matrix layer 116 serving as the alignment marker portion 19 using the sensor unit 41, and performs a process (position correction process) of irradiating the coating film 12A with radiation while correcting the relative position of the photomask 21 with respect to the glass substrate 11 based on the detection result.

[0078] 13, the exposure device 20 is provided with a sensor unit 41, which is capable of detecting the position of the photomask 21 relative to the black matrix layer 116 provided on the glass substrate 11 in a direction perpendicular to the substrate surface (i.e., from above). During scan exposure, the control unit 40 inputs detection data from the sensor unit 41 and detects the position Rb of the photomask 21 (for example, the position of the slit at the outer edge of the first photomask 21a) relative to the black matrix layer 16. Then, the control unit 40 calculates a movement amount ΔR according to the magnitude of the detected relative position Rb, and moves the photomask 21 by the movement amount ΔR.

[0079] For example, as shown in FIG. 14(a), if it is detected that the slit position Tb at the outer edge of the first photomask 21a is shifted inward by θ2 in the width direction relative to the black matrix layer 116 (specifically, the central axis extending in the scanning direction W), the photomask 21 (and thus the exposure unit 26) is moved outward by θ2 in the width direction based on this detection result (see FIG. 14(b)). This aligns the glass substrate 11 with the photomask 21, and the positional relationship (particularly the positional relationship in the width direction) between the region to be exposed of the coating film 12A and the photomask 21 is highly controlled at all times during scanning exposure. As a result, in the liquid crystal layer 13 formed by applying the polymerizable liquid crystal, the linearity of the boundaries of each retardation region 14, 15 and the dimensional stability of the width of each region are ensured from one end to the other end of the coating film 12A in the X direction.

[0080] In the second embodiment, when correcting the widthwise position of the photomask 21 relative to the glass substrate 11 based on the movement amount ΔR, the glass substrate 11 may be moved in the widthwise direction instead of moving the exposure unit 26 in the widthwise direction.

[0081] According to the second embodiment described above in detail, the scanning exposure for obtaining the patterned retardation plate 100 is configured to use the glass substrate 11 on which the black matrix layer 116 is formed, detect the relative position Rb of the photomask 21 with respect to the black matrix layer 116, and perform a process of irradiating the coating film 12A with radiation while correcting the relative position of the photomask 21 with respect to the glass substrate 11 based on the detection result. By forming the liquid crystal layer 13 on the photo-alignment film 12 obtained in this manner, it is possible to manufacture a patterned retardation plate 10 having excellent long-distance dimensional stability of each of the retardation regions 14, 15 by a relatively simple method, even when a large substrate is used.

[0082] Furthermore, since the black matrix layer 116 is formed on the glass substrate 11 and functions as the alignment marker portion 19, there is no need to provide a separate alignment marker portion 19. This makes it possible to suppress an increase in the number of manufacturing steps that would accompany the addition of a new function. Furthermore, since the black matrix layer 116 is formed over the entire substrate surface, by performing scanning exposure using this as a positioning index, the boundary between the first retardation region 14 and the second retardation region 15 can be accurately positioned at a position corresponding to the black matrix layer 116.

[0083] The patterned retardation plate obtained by the manufacturing method of the present invention described above has a large area and excellent long-range dimensional stability of multiple retardation regions in which the alignment orientations of liquid crystal molecules are different from each other. Such a patterned retardation plate is suitable as an optical component to be mounted on a large 3D display. Furthermore, when multiple patterned retardation plates are manufactured by cutting from a single large patterned retardation plate, variation in display quality among the multiple patterned retardation plates can be suppressed, thereby suppressing a decrease in yield.

[0084] The present invention is not limited to the above-described embodiments, and encompasses various modifications and equivalent modifications within the scope of the spirit of the present invention. Therefore, in light of the above teachings, various combinations and forms, as well as other combinations and forms including only one element, more than one element, or less than one element, are to be understood as falling within the scope and spirit of the present invention. [Explanation of symbols]

[0085] 10,100...Patterned retardation plate, 12...Photo-alignment film, 13...Liquid crystal layer, 16,116...Black matrix layer, 19...Alignment marker portion, W...Scanning direction

Claims

1. a film forming step of applying a liquid crystal alignment agent onto a glass substrate to form a coating film; an exposure step of irradiating the coating film with radiation from the light source through the photomask using a plurality of exposure units each including a light source and a photomask to form a photo-alignment film; a liquid crystal layer forming step of forming a liquid crystal layer by applying a polymerizable liquid crystal on the photo-alignment film and curing the liquid crystal; Including, the liquid crystal aligning agent contains a polymer having a cinnamate structure, an azobenzene structure, or a main chain decomposition structure, the glass substrate has an alignment marker portion, which is an index for alignment with the glass substrate, on a substrate surface to which the liquid crystal alignment agent is applied; In the exposure step, scanning exposure is performed in which radiation is irradiated onto the coating film in areas corresponding to the plurality of exposure units while the glass substrate on which the coating film has been formed is moved relatively to the plurality of exposure units in a predetermined movement direction; In the scanning exposure, the relative position of the photomask with respect to the alignment marker portion is detected, and based on the detection result, the coating film is irradiated with radiation while correcting the relative position of the photomask with respect to the glass substrate.

2. 2. The method for producing a patterned retardation film according to claim 1, wherein in the exposure step, the scanning exposure is performed a plurality of times by changing the radiation irradiation area of ​​the coating film, thereby obtaining the photo-alignment film having a plurality of areas in which the alignment orientations of the liquid crystal molecules are different from each other.

3. The method for producing a patterned retardation plate according to claim 2 , wherein the alignment marker portions are formed of a black matrix material.

4. The method for manufacturing a patterned retardation plate according to claim 3 , wherein the alignment marker portions are arranged at positions that overlap boundaries between the plurality of regions when viewed from a direction perpendicular to the substrate surface.

5. 5. The method for producing a patterned retardation plate according to claim 1, wherein in the exposure step, the radiation is irradiated onto the substrate surface from an oblique direction.

6. A glass substrate; a photo-alignment film disposed on the glass substrate; a liquid crystal layer disposed on the photo-alignment film and formed by curing a polymerizable liquid crystal; a black matrix layer; Equipped with the photo-alignment film includes a polymer having a cinnamate structure, an azobenzene structure, or a main chain decomposition structure, and has a plurality of regions in which the alignment directions of liquid crystal molecules are different from each other; The patterned retardation plate is configured such that the black matrix layer is in contact with the glass substrate and overlaps with the boundaries of the plurality of regions when viewed from a direction perpendicular to the substrate surface.

Images