Patent attributes
A liquid crystal display device reduces the color shift problem typically observed at wide viewing angles; the device includes a phase retardation compensation film, a biaxial compensation film, and a liquid crystal display panel between the two films. Refractive indexes of the phase retardation compensation film having a thickness d1 and the biaxial compensation film having a thickness d2 are nx1, ny1, nz1, nx2, ny2, and nz2 in a first, a second and a third directions perpendicular to each other. The third direction is parallel to the normal directions of the surfaces of the phase retardation compensation film and the biaxial compensation film. Optical compensation values of the phase retardation compensation film and the biaxial compensation film are Rth1 and Rth2 and derived from [(nx1+ny1)/2−nz1]×d1 and [(nx2+ny2)/2−nz2]×d2 respectively. Rth1 is not less than 50 nm, and the sum of Rth1 and Rth2 can be equal to 271 nm.