Patent · US Expired

Backlighting device

US5442523A · kind A · utility

73Cited by
11References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 21, 1992
Grant dateAug 15, 1995
Priority date
Expiry dateAug 21, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B6/0071
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In a backlighting device for use with display panels that comprises a light conducting plate made of a light-transmissive material, one of the major faces of said light conducting plate being provided with a light diffusing capability and covered with a specular or light diffusing/reflecting plate, and a linear light source provided in proximity to the end portion of at least one side of said light conducting plate, the improvement wherein at least one sheet that is made of a light-transmissive material and that has a multiple of raised structures having straight ridgelines at minute intervals on the same side in such a manner that the ridgelines are substantially parallel to one another or at least one sheet that is made of a light-transmissive material and that has a multiple of pyramidal or conical projecting structures at minute intervals on the same side, said projecting structures having portions of such a shape that the vertical angles are substantially the same, is provided on the exit face of the light conducting plate in such a way that either type of structures face outward.

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