Patent ID: 9645444
Date: 2017-05-09
CPC Classifications: B32B,F21V,G02B,G02F,H01L

Claim:
1. A retardation film comprising: a first optical anisotropic layer comprising a polymer material; and a second optical anisotropic layer including a liquid crystal material, wherein the first optical anisotropic layer has refractive indices which satisfy the following inequation: nz1≧nx1>ny1, wherein nx1 denotes a refractive index of the first optical anisotropic layer in a direction of a slow axis thereof, ny1 denotes a refractive index of the first optical anisotropic layer in a direction of a fast axis thereof, and nz1 is a refractive index of the first optical anisotropic layer in a thickness direction, which is substantially vertical to the slow axis direction and the fast axis direction of the first optical anisotropic layer, the second optical anisotropic layer has refractive indices which satisfy the following inequation: nx2>ny2≧nz2, wherein nx2 denotes a refractive index of the second optical anisotropic layer in a direction of a slow axis, ny2 denotes a refractive index of the second optical anisotropic layer in a direction of a fast axis thereof, and nz2 is a refractive index of the second optical anisotropic layer in a thickness direction, which is substantially vertical to the slow axis direction and the fast axis direction of the second optical anisotropic layer, refractive indices of the retardation film satisfy the following inequation: 0<(nx0−nz0)/(nx0−ny0)<1, wherein nx0 denotes refractive index of the retardation film in a slow axis thereof, ny0 denotes a refractive index of the retardation film in a fast axis thereof, and nz0 denotes a refractive index of the retardation film in a thickness direction thereof, the fast axis of the first optical anisotropic layer being an elongation direction of the first optical anisotropic layer and the slow axis of the second optical anisotropic layer being an alignment direction of the second optical anisotropic layer, and an angle between the elongation direction of the first optical anisotropic layer and the alignment direction of the second optical anisotropic layer is in a range of about 1° to about 41°, and in-plane retardation values of the retardation film respectively at a wavelength of about 450 nanometers, 550 nanometers and 650 nanometers satisfy the following inequation: Re0 (450 nm)<Re0 (550 nm)<Re0 (650 nm), wherein Re0 (450 nm) denotes an in-plane retardation value of the retardation film at the wavelength of about 450 nanometers, Re0 (550 nm) denotes an in-plane retardation value of the retardation film at the wavelength of about 550 nanometers, and Re0 (650 nm) denotes an in-plane retardation value of the retardation film at the wavelength of about 650 nanometers.