Patent · US Expired

Ferroelectric liquid crystal device

US5227904A · kind A · utility

14Cited by
4References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 12, 1991
Grant dateJul 13, 1993
Priority date
Expiry dateJul 12, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F1/133734
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A ferroelectric liquid crystal device includes a pair of substrates which has electrodes formed in an opposing spatial relation to each other. At least one of the electrodes is optically transparent. A parallel aligned, obliquely evaporated film is formed on each electrode. The paired substrates are sealed to provide a cell. A ferroelectric liquid crystal composition to which an ionic substance having a great mobility is added is placed in the cell to obtain the liquid crystal device. The addition of the ionic substance results in a low switching threshold voltage, a high response speed and good memory reproducibility. When the device is applied with an AC electric field prior to driving, display contrast is significantly improved.

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