Patent ID: 7589802

Claim:
A liquid crystal display device comprising: a liquid crystal display panel in which a liquid crystal layer is held between a pair of mutually opposed substrates; polarizer plates which are disposed on outer surfaces of the pair of substrates; and an area light source unit which is opposed to one of the polarizer plates, wherein the area light source unit includes: a light source; a light guide having a light incidence surface which is opposed to the light source, a light emission surface which emits light that is incident on the light incidence surface, and an opposed surface which is opposed to the light emission surface; and a prismatic sheet which is disposed between said one of the polarizer plates and the light guide, the light guide has prisms on at least one of the light emission surface and the opposed surface, the prismatic sheet has prisms which extend in a direction that is displaced counterclockwise by a first predetermined angle from a direction that is perpendicular to a direction of extension of the prisms of the light guide, and an angle between a polarization axis of said one of the polarizer plates and a polarization axis of the prismatic sheet is set between 0° and 20°.