Patent ID: 6330108
Filing Date: 2001-12-11
Classification: G02B

Abstract:
A composite retarder plate comprising:(A) at least one retarder layer made of a high-molecular film satisfying a relation nx>ny>nz;(B) at least one retarder layer satisfying a relation nx.gtoreq.ny>nz and having an optical axis inclined relative to a direction of a normal line with respect to a plane of the layer (B); and(C) at least one retarder layer satisfying a relation of one of nx>nz.gtoreq.ny and nx>ny>nz,wherein nx and ny are in-plane refractive indices and nz is a refractive index in a direction of thickness of each of said layers (A) to (C), andwherein .DELTA.Nxy and Rth given by Nx.gtoreq.Ny, (Nx-Ny).multidot.D=.DELTA.Nxy and {(Nx+Ny)/2-Nz}.multidot.D=Rth and based on monochromatic light with a wavelength of 590 nm are in a range of from 25 to 100 nm and in a range of from 100 to 300 nm respectively when Nx and Ny are in-plane refractive indices in said composite retarder plate, Nz is a refractive index in a direction of thickness of said composite retarder plate and D is the thickness of said composite retarder plate.