Abstract: A wide viewing angle compensation polarizing plate of the invention comprises a laminate comprising an optical film (1) that is formed of an obliquely oriented material exhibiting optically-negative uniaxiality, an anisotropic light-scattering film (2) and a polarizer (3). The wide viewing angle compensation polarizing plate can widen viewing angle characteristics both in the lateral and vertical directions with respect to the direction of the normal to the screen when used in liquid crystal displays.

Abstract: The present invention provides a composite birefringent member including a first birefringent layer and a second birefringent layer. The second birefringent layer is formed on at least one surface of the first birefringent layer. In the wavelength range from 400 to 800 nm, a value of ?ndx/?nd550 and a value of Rthx/Rth550 of the composite birefringent member as a whole are different from each other. The composite birefringent member satisfies a requirement that the second birefringent layer is formed of a polymer such as polyamide and/or a requirement that ?nd and Rth of the composite birefringent member satisfy formulae (I) and (II) below. As a result, the composite birefringent member allows a liquid crystal display to achieve a wide viewing angle, compensates birefringence of a liquid crystal cell, and does not cause display coloring of the liquid crystal display. ?nd400/?nd550<1 ??(I) Rth400/Rth550>1 ??(II).

Abstract: The present invention provides a birefringent optical film that allows a liquid crystal display to achieve excellent contrast and a wide viewing angle and does not cause coloring of the liquid crystal display. The birefringent optical film includes at least one birefringent A-layer having a property satisfying nya?nza>nxa or nza>nya>nza and at least one birefringent B-layer having a property satisfying nxb?nyb>nzb.

Abstract: It is an object of the present invention to provide a method for manufacturing a birefringent film that can reduce the amount of a remaining solvent in the birefringent film without degrading appearance uniformity or an alignment in its thickness direction. The method of the present invention for manufacturing an optical film includes the steps of: coating a base with a polymer solution obtained by dissolving a polyimide-containing polymer in a solvent so as to form a coating film; and drying the coating film so as to form a birefringent film, in which the drying step includes at least two stages of drying processes. The drying step preferably include two stages of the drying processes, and a temperature in the former stage of the drying process is preferably lower than a temperature in the latter stage of the drying process. If adding a step of providing the birefringent film with an anisotropy of a refractive index in an in-plane direction, a birefringent film with an optical biaxiality can be manufactured.

Abstract: A wide viewing angle compensation polarizing plate of the invention comprises a laminate comprising an optical film (1) that is formed of an obliquely oriented material exhibiting optically-negative uniaxiality, an anisotropic light-scattering film (2) and a polarizer (3). The wide viewing angle compensation polarizing plate can widen viewing angle characteristics both in the lateral and vertical directions with respect to the direction of the normal to the screen when used in liquid crystal displays.

Abstract: A method of manufacturing a birefringent film is provided, by which a birefringent film including a liquid crystal compound birefringent layer and another birefringent layer can be manufactured so as to have a reduced thickness in a reduced number of process steps. In the manufacturing method, a non-liquid crystal polymer birefringent layer that has been subjected to an aligning treatment is used as an alignment layer for a liquid crystal compound. According to the manufacturing method, the process step of separately preparing an alignment layer and the need for the additional alignment layer can be eliminated, thereby allowing the total thickness of the birefringent film to be reduced.

Abstract: The present invention relates to an optical film that is excellent in optical properties and can be produced at low cost. In the optical film formed by laminating a transparent polymer film layer and a birefringent layer of a non-liquid crystalline polymer, the birefringent layer satisfies a condition represented by nx?ny>nz and the in-plane retardation of the transparent polymer film layer is 50 nm or less. In the above formula, nx, ny and nz are the refraction indices in the X-, Y- and Z-axes directions of the birefringent layer, respectively. The X-axis direction is the axial direction in which the refraction index shows a maximum value in the in-plane direction of the birefringent layer, the Y-axis direction is the axial direction perpendicular to the X-axis direction in the plane, and the Z-axis direction is the thickness direction perpendicular to the X- and Y-axes directions.

Abstract: An optical film, which includes a laminate of a base and a birefringent layer, and which is excellent in adhesiveness between the base and the birefringent layer, is provided. The birefringent layer is formed on the base by: coating a material of the birefringent layer on the base so as to form a coating film; stretching/shrinking the base so as to stretch/shrink the coating film; and solidifying the material of the coating film. The material is dispersed or dissolved previously in a solvent and coated in a form of solution, where the solvent used exhibits solubility with respect to the base, and in the coating step, the solvent is infiltrated into a part of the interior of the base, thereby obtaining an optical film with excellent adhesiveness between the base and the birefringent layer.

Abstract: A liquid crystal panel that has a high contrast ratio over a wide range and can suppress color shifting effectively is provided. In a liquid crystal panel including between two polarizing plates arranged in a crossed Nicols state a birefringent layer A with nx>ny?nz, a birefringent layer B with nx?ny>nz and a VA-mode liquid crystal cell C, it is set that a wavelength dispersion characteristic (?40(A)) of the birefringent layer A, the birefringent layer B (?40(B)) and (?40(C)) of the liquid crystal cell C satisfy conditions ?40(B)>?40(C)>?40(A) and 1>?40(A). The wavelength dispersion characteristic ?40 represents a ratio of a retardation Re measured with incident light at 430 nm to that measured with incident light at 550 nm, the incident light being inclined by 40° with respect to a normal direction (0°) of a surface of the birefringent layer or a surface of the liquid crystal cell.

Abstract: A liquid crystal panel that has a high contrast ratio over a wide range and can suppress color shifting effectively is provided. In a liquid crystal panel including between two polarizing plates arranged in a crossed Nicols state a birefringent layer A with nx>ny?nz, a birefringent layer B with nx?ny>nz and a VA-mode liquid crystal cell C, it is set that a wavelength dispersion characteristic (?40(A)) of the birefringent layer A, a wavelength dispersion characteristic (?40(B)) of the birefringent layer B and a wavelength dispersion characteristic (?40(C)) of the liquid crystal cell C satisfy conditions ?40(B)>?40(C)>?40(A) and 1>?40(A). The wavelength dispersion characteristic ?40 represents a ratio of a retardation Re measured with incident light at 430 nm to that measured with incident light at 550 nm, the incident light being inclined by 40° with respect to a normal direction (0°) of a surface of the birefringent layer or a surface of the liquid crystal cell.

Abstract: The present invention provides a birefringent optical film having a high orientation for easily obtaining a desired retardation value and also a small photoelastic coefficient. The birefringent optical film includes at least two kinds of polymer materials. A total of products of Cn and Wn satisfies a numerical formula (1): ?(Cn×Wn)?30×10?8 cm2/N??(1) where Cn and Wn denote respectively a photoelastic coefficient and a volume fraction of each polymer material, and at least one of the polymer materials of the film has a photoelastic coefficient value of at least 60×10?8 cm2/N.

Abstract: An optical device including a laminate of cholesteric liquid-crystal layers in which the wavelength ranges of selective reflection of circularly polarized light beams are out of visible light region and which are combined so that circularly polarized light beams transmitted through the cholesteric liquid-crystal layers to be left-handed and right-handed are inverted to each other. A liquid-crystal display apparatus including a vertically aligned liquid-crystal cell, polarizers disposed on opposite surfaces of the liquid-crystal cell, and one or two optical devices defined above and interposed between the liquid-crystal cell and either or each of the polarizers.

Abstract: An optical film including a transparent polymer film (b) and a birefringent layer (a) formed of a polymer and laminated above the transparent polymer film (b) is provided. The birefringent layer (a) and the transparent polymer film (b) satisfy the following formula (1), the birefringent layer (a) satisfies the following formulae (2) and (3), and the polymer forming the birefringent layer (a) has a weight-average molecular weight in the range between 10,000 and 400,000 inclusive. ?n(a)>?n(b)×10??(1) 1<(nx?nz)/(nx?ny)??(2) 0.0005??n(a)?0.5??(3) This optical film can prevent the occurrence of iridescence, the occurrence of cracks, and the occurrence of variation in retardation.

Abstract: An optical film, which includes a laminate of a base and a birefringent layer, and which is excellent in adhesiveness between the base and the birefringent layer, is provided. The birefringent layer is formed on the base by: coating a material of the birefringent layer on the base so as to form a coating film; stretching/shrinking the base so as to stretch/shrink the coating film; and solidifying the material of the coating film. The material is dispersed or dissolved previously in a solvent and coated in a form of solution, where the solvent used exhibits solubility with respect to the base, and in the coating step, the solvent is infiltrated into a part of the interior of the base, thereby obtaining an optical film with excellent adhesiveness between the base and the birefringent layer.

Abstract: The present invention provides a composite birefringent member including a first birefringent layer and a second birefringent layer. The second birefringent layer is formed on at least one surface of the first birefringent layer. In the wavelength range from 400 to 800 nm, a value of ?ndx/?nd550 and a value of Rthx/Rth550 of the composite birefringent member as a whole are different from each other. The composite birefringent member satisfies a requirement that the second birefringent layer is formed of a polymer such as polyamide and/or a requirement that ?nd and Rth of the composite birefringent member satisfy formulae (I) and (II) below. As a result, the composite birefringent member allows a liquid crystal display to achieve a wide viewing angle, compensates birefringence of a liquid crystal cell, and does not cause display coloring of the liquid crystal display.

Abstract: The present invention provides a birefringent optical film having a high orientation for easily obtaining a desired retardation value and also a small photoelastic coefficient. The birefringent optical film includes at least two kinds of polymer materials. A total of products of Cn and Wn satisfies a numerical formula (1): ?(Cn×Wn)?20×10?8 cm2/N??(1) where Cn and Wn denote respectively a photoelastic coefficient and a volume fraction of each polymer material, and at least one of the polymer materials of the film has a photoelastic coefficient value of at least 60×10?8 cm2/N, while at least one of the remaining polymer materials has a negative value of photoelastic coefficient.

Abstract: The present invention provides a transparent optical film that has excellent optical characteristics for realizing the uniform retardation distribution and restraining rainbow-colored irregularities. The optical film, which is obtained by laminating a birefringent layer (a) on a transparent film (b), satisfies all the following formulae (I), (II) and (III). ?n(a)>?n(b)×10??(I) 1<(nx?nz)/(nx?ny)??(II) 0.0005??n(a)?0.5??(III) In the above formulae (I), (II) and (III), ?n(a) and ?n(b) denote respectively birefringent indexes of the birefringent layer (a) and the transparent film (b). The signs of nx, ny and nz indicate refractive indexes in an X-axis direction, a Y-axis direction and a Z-axis direction in the birefringent layer (a), respectively.

Abstract: The present invention provides a birefringent optical film that allows a liquid crystal display to achieve excellent contrast and a wide viewing angle and does not cause coloring of the liquid crystal display. The birefringent optical film includes at least one birefringent A-layer having a property satisfying nya?nza>nxa or nza>nya>nza and at least one birefringent B-layer having a property satisfying nxb?nyb>nzb.

Abstract: The present invention relates to an optical film that is excellent in optical properties and can be produced at low cost. In the optical film formed by laminating a transparent polymer film layer and a birefringent layer of a non-liquid crystalline polymer, the birefringent layer satisfies a condition represented by nx?ny>nz and the in-plane retardation of the transparent polymer film layer is 50 nm or less. In the above formula, nx, ny and nz are the refraction indices in the X-, Y- and Z-axes directions of the birefringent layer, respectively. The X-axis direction is the axial direction in which the refraction index shows a maximum value in the in-plane direction of the birefringent layer, the Y-axis direction is the axial direction perpendicular to the X-axis direction in the plane, and the Z-axis direction is the thickness direction perpendicular to the X- and Y-axes directions.

Abstract: An optical film including a transparent polymer film (b) and a birefringent layer (a) formed of a polymer and laminated above the transparent polymer film (b) is provided. The birefringent layer (a) and the transparent polymer film (b) satisfy the following formula (1), the birefringent layer (a) satisfies the following formulae (2) and (3), and the polymer forming the birefringent layer (a) has a weight-average molecular weight in the range between 10,000 and 400,000 inclusive. ?n(a)>?n(b)×10??(1) 1<(nx?nz)/(nx?ny)??(2) 0.0005??n(a)?0.5??(3) This optical film can prevent the occurrence of iridescence, the occurrence of cracks, and the occurrence of variation in retardation.