Phase retarder

摘要

A phase retarder comprises a layered inorganic compound sheet or film in which the refractive index in the plane thereof differs from the refractive index in the thickness direction. Preferably the inorganic compound is a clay mineral having a mean particle size of 5,000 nm or less, and the sheet or film contains an optically transparent resin, eg vinylalcohol polymer, in an inorganic compound/resin ratio of 0.1 10.0. The phase retarder can be used for improving the display properties of various liquid crystal display devices.