Patent ID: 7180561
Filing Date: 2007-02-20
Classification: G02F

Abstract:
1. A liquid crystal display device including: (a) a liquid crystal cell comprised of a pair of substrates each having at least one electrode formed thereon, and a liquid crystal layer sandwiched between said substrates; (b) a first polarizer arranged to face said liquid crystal cell; (c) a second polarizer arranged to face said liquid crystal cell at the opposite side of said first polarizer; (d) a first retardation plate arranged between said first polarizer and said liquid crystal cell; (e) a second retardation plate arranged between said second polarizer and said liquid crystal cell; and (f) an optical layer having negative uniaxial retardation and arranged at least one of between said first retardation plate and said liquid crystal cell, between said second retardation plate and said liquid crystal cell, between said first retardation plate and said first polarizer, and between said second retardation plate and said second polarizer, wherein each of said first and second retardation plates has a lagging axis in a plane disposed in parallel with said substrates, and has retardation of almost λ/4, lagging axes of said first and second retardation plates being perpendicular with each other, said first polarizer has an absorption axis inclining by about 45 degrees relative to said lagging axis of said first retardation plate, and inclining by about 90 degrees relative to an absorption axis of said second polarizer, said liquid crystal layer is composed of liquid crystal which has negative dielectric anisotropy and which is aligned vertically when no voltage is applied thereto, and aligned in four directions when a voltage is applied thereto, and said absorption axes of said first and second polarizers are angularly deviated such that characteristic of a viewing angle in said liquid crystal display device is rendered symmetric, relative to a symmetry axis about which said liquid crystal in said liquid crystal layer is aligned in different directions.