Patent · US Expired

Surface light source device

US5572411A · kind A · utility

53Cited by
3References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 5, 1995
Grant dateNov 5, 1996
Priority date
Expiry dateJan 5, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F1/133607
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The present invention has its purpose to obtain a bright luminescent in a surface light source device using a light conducting member. In the surface light source device according to the present invention, a light source is disposed in the vicinity of a light incident edge surface of the light conducting member, a light diffusing plate is arranged on the light emitting side of the light conducting member, and a prism sheet having a multiplicity of convex portions is provided on a side of the light diffusing member, which is opposite to the side where the light conducting member is arranged: and further each of the convex portion of the prism sheet is arranged such that the inclined angle on the light source side is smaller than the inclined angle on the opposite side thereof. Therefore, the luminescent light is directed to the portion to be illuminated of the liquid crystal display apparatus and thus a bright luminescent can be obtained.

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