Patent ID: 7388636
Filing Date: 2008-06-17
Classification: G02B,G02F

Abstract:
1. An optical film for a liquid crystal display obtained by laminating a polarizing plate and a retardation film so that an absorption axis of the polarizing plate and a slow axis of the retardation film are perpendicular or parallel to each other, wherein the optical film is applied to an IPS mode liquid crystal display comprising a liquid crystal cell driven in IPS mode, wherein the polarizing plate comprises a transparent protective film on both surfaces of a polarizer and if a direction on the transparent protective film in which an in-plane refractive index is maximized is X axis, a direction perpendicular to X axis is Y axis, a direction of the film thickness is Z axis; and refractive indexes at 550 nm in the respective axes directions are nx an in-plane retardation Re a thickness direction retardation Rth={(nx wherein if a direction on the retardation film in which an in-plane refractive index is maximized is X axis, a direction perpendicular to X axis is Y axis, a direction perpendicular to X axis is Y axis, a direction of the film thickness is Z axis; and refractive indexes at 550 nm in the respective axes directions are nx an Nz value represented by Nz=(nx an in-plane retardation Re