Patent · US Expired

Light modulator

US6646710B2 · kind B2 · utility

12Cited by
9References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 26, 2001
Grant dateNov 11, 2003
Priority date
Expiry dateApr 27, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F1/1414
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A bright, and contrasty reflective display can be performed without using polarizer films, and display switching can be performed fast. A ferroelectric liquid crystal is sandwiched between substrates, and electrodes are formed face to face with each other in a direction parallel to the substrates. The ferroelectric liquid crystal, when no electric field is applied to it, goes into a planer state in which a helical axis becomes perpendicular to or almost perpendicular to the substrates, selectively reflecting light of specific wavelengths in a visible region. A driving circuit applies an electric field between the electrodes in a direction perpendicular to or almost perpendicular to the helical axis of the ferroelectric liquid crystal in the planer state. When an electric field equal to or greater than a threshold value is applied, the ferroelectric liquid crystal changes from a planer state due to a low electric field to a homeotropic state in which a helical structure disappears, going into a transparent state, wherein, in the homeotropic state, a cyclic change of refractive index disappears and liquid crystal molecules are arranged in the direction of the electric field. The chan…

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