Patent · US Expired

High output flat-panel display back light module

US6341879B1 · kind B1 · utility

30Cited by
18References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 28, 1999
Grant dateJan 29, 2002
Priority date
Expiry dateSep 28, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F2201/36
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The present invention features a system for uniformly distributing luminance and a high degree of collimation from a back light module for a flat-panel, liquid crystal display (LCD). A constant and uniform luminance output of the back light module is obtained through appropriate selection of lamps, geometry and optical components. An appropriate balance of lamps, lamp spacing, reflective light back plane, and diffuser and collimating optics are chosen to produce a high brightness back light module with very high intensity output over very large surfaces. Variations in intensity over the illuminated area are minimized using light recycling in conjunction with the collimating optics. Optimum geometries are determined for the purpose of maximizing light output at high efficiencies, while minimizing luminance gradients across the display. Finally, a precise collimator eliminates light beyond a defined angle, as required in a tiled, flat-panel LCD.

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