Patent ID: 6710830
Filing Date: 2004-03-23
Classification: G02F

Abstract:
An optical sheet comprising:a retardation film; and a transparent layer provided on one of opposite surfaces of said retardation film; wherein said retardation film exhibits Nz=(nxâˆ’nz)/(nxâˆ’ny) in a range of from 0.1 to 0.4 and (nxâˆ’ny)d in a range of from 200 to 350 nm in which d is a thickness of said retardation film, nz is a refractive index in a direction of a Z axis expressing a direction of the thickness d of said retardation film, nx is a refractive index in a direction of an X axis expressing a direction of said retardation film in a plane perpendicular to said Z axis while said X axis also expresses a direction of the highest in-plane refractive index, and ny is a refractive index in a direction of a Y axis expressing a direction of said retardation film perpendicular both to said Z axis and to said X axis; and wherein said transparent layer has a thickness not larger than 10 &mgr;m and exhibits refractive index anisotropy of nx&ap;ny>nz.