Patent ID: 6795246
Filing Date: 2004-09-21
Classification: G02F

Abstract:
An optical film comprising:a first birefringent film having Re of from 200 to 350 nm and Nz of from 0.6 to 0.9; and a second birefringent film having Re of from 100 to 175 nm and Nz of from 0.3 to 0.7, and laminated on said first birefringent film so that optical axes of said first and second birefringent film intersect each other, in which Re and Nz are given by relations (nxâˆ’ny)d=Re and (nx=nz)/(nxâˆ’ny)=Nz, nz is a refractive index of corresponding one of said first and second birefringent films in a direction of a Z axis indicating a direction of a thickness of the birefringent film, nx is a refractive index of the birefringent film in a direction of an X axis indicating a direction of a highest refractive index in a plane perpendicular to the Z axis, ny is a refractive index of the birefringent film in a direction of a Y axis perpendicular both to the X axis and to the Z axis, and d is the thickness of the birefringent film.