Patent · US Expired

Cold cathode backlight for avionics applications with strobe expanded dimming range

US6494587B1 · kind B1 · utility

46Cited by
8References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 24, 2000
Grant dateDec 17, 2002
Priority date
Expiry dateNov 3, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2320/0633
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method of backlighting a flat panel display over an expanded dimming range includes providing a backlight including multiple cold cathode fluorescent lamps positionable directly behind a diffuser. Each of multiple drive circuits is adapted to independently adjust arc current of at least one of the multiple cold cathode fluorescent lamps in order to change the luminance output of the at least one of the cold cathode fluorescent lamps. Control signals are provided to each of the multiple drive circuits to separately control luminance output of different cold cathode fluorescent lamps such that at the same instant the different cold cathode fluorescent lamps are driven to substantially different luminance intensities, thereby allowing a reduction of an overall minimum luminance provided by the backlight and expanding the dimmable range of the backlight. A backlight implementing the methods of the invention is also disclosed.

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