Patent · US Expired

Waveform sequencing method and apparatus for a bistable cholesteric liquid crystal display

US6911965B2 · kind B2 · utility

3Cited by
7References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 28, 2003
Grant dateJun 28, 2005
Priority date
Expiry dateJan 9, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2320/0233
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Reflective chiral nematic liquid crystal material is disposed between a first set of electrodes and a second set of electrodes arranged on opposed sides of the material to define a collection of pixels. Fast updating dynamic drive scheme is implemented by selectively applying an electric field via the electrodes through the pixels in four phases of energization: preparation, selection, evolution, and non-select. Each phase is made up of a series of voltages having varying amplitudes. The voltage waveform is for each phase controlled based on the selection phase to achieve image uniformity. For example, the evolution voltages that are established across adjacent pixels having the same final state have initial amplitudes that are equal for both pixels to increase image uniformity.

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