Patent · US Expired

Nematic liquid crystal storage display device

US4601542A · kind A · utility

9Cited by
2References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 17, 1985
Grant dateJul 22, 1986
Priority date
Expiry dateOct 17, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F1/1391
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A bistable nematic liquid crystal display cell is electrically switched between topologically equivalent, asymmetric horizontal states. Switching is initiated by application of a symmetry breaking field such as a DC electric field of a predetermined polarity. An AC electric potential is then applied across the cell to complete the switching cycle and maintain the state. The cell includes upper and lower parallel substrates, upper and lower topographically textured tilt alignment surfaces on the corresponding substrates, and nematic liquid crystal material between the substrates. In an active region of the cell, the tilt alignment surfaces form an equal reverse tilt boundary condition. In an isolation region surrounding the active region of the cell, the tilt alignment surfaces are formed to have a parallel tilt boundary condition.

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