Quarter wave plate comprising two optically anisotropic layers
AssigneeFuji Photo Film Co., Ltd.
InventorsKohei Arakawa, Ken Kawata, Mitsuyoshi Ichihashi
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Abstract
A circularly polarizing plate comprises a linearly polarizing membrane and a quarter wave plate. The quarter wave plate comprises an optically anisotropic layer A and an optically anisotropic layer B. The quarter wave plate has such an optical characteristic that a retardation value essentially is a quarter of a wavelength when the retardation value is measured at the wavelength of 450 nm, 550 nm and 650 nm. One of the optically anisotropic layers A and B is a layer made from liquid crystal molecules, and the other is a polymer film or a layer made from liquid crystal molecules.
Claims11
A quarter wave plate comprising an optically anisotropic layer A and an optically anisotropic layer B, said quarter wave plate having such an optical characteristic that a retardation value essentially is a quarter of a wavelength when the retardation value is measured at the wavelength of 450 nm, 550 nm and 650 nm, wherein one of the optically anisotropic layers A and B is a layer made from discotic liquid crystal molecules, and the other is a polymer film or a layer made from liquid crystal molecules, and wherein the discotic liquid crystal molecules are aligned at an average inclined angle in the range of 50° to 90°, said inclined angle being an angle between a plane of a discotic core of the discotic liquid crystal molecules and a surface plane of the optically anisotropic layer.
A quarter wave plate comprising an optically anisotropic layer A and an optically anisotropic layer B, said quarter wave plate having such an optical characteristic that a retardation value essentially is a quarter of a wavelength when the retardation value is measured at the wavelength of 450 nm, 550 nm and 650 nm, wherein one of the optically anisotropic layers A and B is a layer made from liquid crystal molecules, and the other is a polymer film or a layer made from liquid crystal molecules, wherein each of the optically anisotropic layers A and B has a slow axis in plane, and wherein an angle between the slow axis of the optically anisotropic layer A and the slow axis of the optically anisotropic layer B is in the range of 75° to 105°, wherein the quarter wave plate further comprises a transparent support having a lengthwise direction, and wherein an angle between the lengthwise direction and the slow axis of the optically anisotropic layer A is in the range of 40° to 50°, and an angle between the lengthwise direction and the slow axis of the optically anisotropic layer B is in the range of 40° to 50°.
A quarter wave plate comprising an optically anisotropic layer A and an optically anisotropic layer B, said quarter wave plate having such an optical characteristic that a retardation value essentially is a quarter of a wavelength when the retardation value is measured at the wavelength of 450 nm, 550 nm and 650 nm, wherein each of the optically anisotropic layers A and B has a slow axis in plane, and wherein an angle between the slow axis of the optically anisotropic layer A and the slow axis of the optically anisotropic layer B is in the range of 50° to 70°, wherein the quarter wave plate further comprises a transparent support having a lengthwise direction, and wherein an angle between the lengthwise direction and the slow axis of one of the optically anisotropic layers A and B is in the range of 60° to 80°, and an angle between the lengthwise direction and the slow axis of the other is in the range of 10° to 30°.
Dependencies are inferred from the claim text.