Patent · US Expired

Optically compensating film, optical compensator, and liquid crystal display incorporating the same

US5343317A · kind A · utility

10Cited by
2References
10Claims
0Family size

Assignees

Inventors

Key dates

Filing dateApr 14, 1993
Grant dateAug 30, 1994
Priority date
Expiry dateApr 14, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F2413/08
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A polymer film from a composition comprising a polymer (A) giving a film with a refractive index of n.sub.D .gtoreq.1.60, an Abbe number of .nu..sub.D .ltoreq.30.0 and a glass transition temperature of Tg=60.degree. to 160.degree. C. and a polymer (B) giving a film with a refractive index of n.sub.D <1.60 is oriented at least in one direction to provide an oriented film. It is arranged that this oriented film has a retardation value of R-60-1000 nm and a wavelength dispersion value of .nu..sub.RF .gtoreq.1.10. An optically compensating film comprising this oriented film or an optical compensator comprising the oriented film and an optically isotropic film laminated at least on one side thereof is used for color compensation in a liquid crystal display panel. In this manner, a liquid crystal display device solving the long-standing problems of coloration and low contrast ratio is obtained.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.