Light diffuser for a liquid crystal display
US5390085A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 1993 |
| Grant date | Feb 14, 1995 |
| Priority date | — |
| Expiry date | Nov 19, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S362/802
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A light diffuser (100) for illuminating a display (304) comprises a rectangular light distributor (108) which is coupled to a light director (208) located along an edge normal to a major axis (110) of the light distributor (108). The light director (208) directs light received from a lamp (14) into the light distributor (108). The light distributor (108) has a polished, planar top surface (210) and a bottom surface (112) comprising a predetermined serration pattern oriented normal to the major axis (110) of the rectangular light distributor (108). The predetermined serration pattern comprises a plurality of grooves (116, 118, 120) having a predetermined pitch gradient corresponding thereto. The plurality of grooves (116, 118, 120) further have roughened surfaces for diffusing light impinging thereon toward the polished, planar top surface (210) of the light distributor (108). The light impinging on the polished, planar top surface (210) at less than a critical angle is coupled through the polished, planar top surface (210 ) to uniformly illuminate the display (304).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.