Patent · US Expired

Surface light source device of side light type

US5788356A · kind A · utility

31Cited by
6References
24Claims
0Family size

Assignees

Inventors

Key dates

Filing dateMar 27, 1996
Grant dateAug 4, 1998
Priority date
Expiry dateMar 27, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B6/0053
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In a surface light source device of side light type, occurrence of irregularities in luminance is prevented in the vicinity of an incidence surface 10 of a light guide plate 1. A light source element 2 is disposed on a lateral side of the light guide plate 1 and the light introduced into the light guide plate 1 through the incidence surface 10 is emitted through an emission surface 11. The light comes outside after undergoing the action of an additional element 3 (such as a priority traveling direction correcting action) and is applied to, for example, back lighting in a liquid crystal display. A reflection sheet such as a silver foil is disposed along a rear surface 12. The rear surface 12 is treated in various manners in order to reflect the light toward the emission surface 11. Another reflection sheet 20 is disposed as a reflector surrounding the light source element 2 from the back side. A case 4 partially projects inward along the incidence surface 10 to form light shielding walls 8, 9. The shielding walls 8, 9 are adapted to prevent light emitted from the light source element 2 from intruding through gaps G1 to G4 between the elements, or through an end surface of an end edg…

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