Patent ID: 7106395

Claim:
A liquid crystal display device, comprising: a liquid crystal display panel that includes: a first substrate and a second substrate disposed so as to oppose each other; a liquid crystal layer sandwiched between the two substrates; and a first polarizer and a second polarizer respectively disposed on opposite sides of the liquid crystal layer; and an illumination device disposed to one side of the liquid crystal display panel, the illumination device including a prism sheet which has a prism surface having a plurality of ribs, each having an approximately triangular cross-section, close to the liquid crystal display panel, and which is arranged such that the prism surface faces in the opposite direction to the liquid crystal display panel, and the second polarizer having a light diffusing layer and a reflective polarizer disposed in that order on an outer surface of the second polarizer, the reflective polarizer having a transmissive polarization axis, each rib having two inclined surfaces, light from the liquid crystal display panel reflecting from a first inclined surface of a first rib, falling incident on the first inclined surface of a second rib, which is adjacent to the first rib, reflecting off a second inclined surface of the second rib, and passing through a surface of the prism sheet that faces the liquid crystal display panel.