Patent ID: 7227602

Claim:
An in-plane switching liquid crystal display comprising: a first polarizer plate; a liquid crystal cell, which is horizontally aligned and filled with liquid crystal of positive dielectric anisotropy (Δ∈>0), an optical axis of the liquid crystal filled in the liquid crystal cell being aligned in-plane in parallel to polarizer plate; and a second polarizer plate, wherein an absorption axis of the first polarizer plate is perpendicular to an absorption axis of the second polarizer plate, and the optical axis of the liquid crystal filled in the liquid crystal cell is parallel to the absorption axis of the first polarizer plate, wherein at least one +A-plate (n x >n y =n z ) and at least one +C-plate (n x =n y <n z ) are interposed between one of the first and second polarizer plates and the liquid crystal cell in order to compensate for a viewing angle in a dark state, and an optical axis of the +A-plate is adjusted according to an alignment order of +A-plates and +C-plates, in which n x and n y represent an in-plane refractive index, n z represents a thickness refractive index, the A-plate has an in-plane retardation value of R in =d×(n x −n y ), and the +C-plate has a thickness retardation value of R in =d×(n z −n y ), wherein d is a thickness of a retardation film.