Patent ID: 7948592
Filing Date: 2011-05-24
Classification: G02F

Abstract:
1. A display device, comprising: a display panel comprising a first substrate, a second substrate, and a liquid crystal layer disposed between the first substrate and the second substrate, the liquid crystal layer being vertically aligned; a first optical unit comprising a C-plate and a first polarization plate having a first absorption axis; and a second optical unit comprising a positive A-plate, a negative A-plate disposed over the positive A-plate in a proceeding direction of light, and a second polarization plate having a second absorption axis substantially perpendicular to the first absorption axis, wherein the negative A-plate is a phase retardation film having a thickness-direction phase retardation value (Rth) that satisfies a numerical condition of Rth≦0 and nx≠ny, the positive A-plate is a phase retardation film having the thickness-direction phase retardation value (Rth) that satisfies a numerical condition of Rth≧0 and nx≠ny, and the C-plate is a negative C-plate satisfying a numerical condition of “nx=ny>nz,”; wherein Rth={(nx+ny)/2−nz}×d, and “d” is a thickness of the phase retardation film; “nx” represents a refractive index in an x-axis direction, and “ny” represents a refractive index in a y-axis direction substantially perpendicular to the x-axis; and “nz” represents a refractive index in a z-axis direction substantially perpendicular to the x-axis direction and the y-axis direction.