Patent · US Expired

Holographically-formed polymer dispersed liquid crystals with multiple gratings

US6538775B1 · kind B1 · utility

25Cited by
6References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 16, 1999
Grant dateMar 25, 2003
Priority date
Expiry dateSep 16, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03H2260/33
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A multicolored reflection liquid crystal display device includes a pair of substrates having a reflective holographic polymer dispersed liquid crystal (H-PDLC) film disposed therebetween. The H-PDLC film contains at least two different reflection gratings capable of reflecting two different wavelengths of light. A multicolored reflection H-PDLC is obtained by simultaneously illuminating a plurality of regions of a film comprised of a mixture of a liquid crystal and a photo-polymerizable monomer with a plurality of holographic light patterns capable of providing liquid crystal layers of different spacings so as to obtain different reflection gratings in each of the regions. A mask is placed between each of the laser light beams and the film to form a pattern of light and dark regions on the film. Each mask is positioned such that at least one light region of a first beam pair coincides with at least one dark region of a second beam pair within the film. A multiple grating liquid crystal display device including an H-PDLC film having a first region comprising liquid crystal and matrix polymer layers forming a transmission grating and a second region comprising liquid crystal and matr…

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