Patent · US Expired

Liquid crystal cell using the electrically controlled birefringence effect and a uniaxial medium of negative optical anisotropy usable therein

US4889412A · kind A · utility

251Cited by
2References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 17, 1987
Grant dateDec 26, 1989
Priority date
Expiry dateFeb 17, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F1/133742
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

Liquid crystal cell using the electrically controlled birefringence effect and processes for the production of the cell and a uniaxial medium or material of negative optical anistropy usable therein. The cell can comprise two crossed rectilinear polarizers, two glass plates provided with transparent electrodes and placed between said polarizers, a liquid crystal layer between the plates and, between a plate and a polarizer, a layer of a negative uniaxial thermoplastic polymer having its extraordinary axis perpendicular to the plates. This layer can be obtained by heating the polymer up to the isotropic state, under a uniform presure on the polarizers, cooling and eliminating the pressure. Application to the production of data display devices.

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