Patent · US Expired

Surface light source device of side light type and liquid crystal display

US6211929A · kind A · utility

2Cited by
9References
10Claims
0Family size

Assignees

Inventors

Key dates

Filing dateAug 24, 1999
Grant dateApr 3, 2001
Priority date
Expiry dateAug 24, 2019

Classification

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

Abstract

A liquid crystal display includes a LCD panel and a surface light source device of side light type to illuminate the panel. The surface light source device comprises a guide plate having an emission face, a back face and an incidence face, a primary light source to supply light through the incidence face, and a reflection member disposed along the back face. The reflection member has an inner reflection face including a plurality of fine regions to control angular extension of illumination output. The fine regions are provided with scattering property which is different from that of the rest region. In cases where emission promoting power (scattering power) of the emission face falls according to distance from the incidence face, the reflection face of the reflection member is provided with scattering power which varies so as to tend to compensate said falling of emission promoting power. Fine regions are arranged in corner portions located at both ends of the incidence face to avoid short of emission. Employment of a reflection member provided with fine regions controls angular extension of illumination output, thereby preventing bright-dark unevenness from appearing under ranging…

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