Patent · US Expired

Wedge-shaped liquid crystal cell

US5841500A · kind A · utility

73Cited by
9References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 9, 1997
Grant dateNov 24, 1998
Priority date
Expiry dateJan 9, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04Q2011/0035
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A liquid-crystal cell having plates defining a gap between them which is filled with a liquid crystal, especially a twisted nematic. The plates are made non-parallel to a predetermined degree so that the liquid crystal assumes a wedge shape, producing different effective thicknesses of the liquid crystal depending on the lateral position within the cell. In use, a narrow beam irradiates a portion of the cell, and the cell is positioned along the wedge direction so as to optimize the cell performance. The invention is particularly useful with a liquid-crystal multi-wavelength switch, which requires extinction ratios between the two states of the cell.

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