Surface light source device of side light type
US6155692A · kind A · utility
Assignees
Inventor
Key dates
| Filing date | Oct 8, 1998 |
| Grant date | Dec 5, 2000 |
| Priority date | — |
| Expiry date | Oct 8, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S385/901
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A surface light source device of side light type is provided with guide plate, a primary light source, a reflection sheet and a prism sheet. The back surface of the guide plate provides a light control surface (arrows D to F). This light control surface has a great number of projections running generally at right angles to an incidence end surface. Each projection includes a pair of slopes. Inclination angles of the slopes of the pair with respect to a normal to a general plane of the guide plate are equal to each other on a generally central portion of an emission surface, while inclination angles of respective inner slopes become larger gradually than those of respective outer slopes toward areas near both side portions, as viewed from an incidence end surface. Length between two side edges of the guide plate may be larger than length thereof along the running direction of the projections, as viewed from the incidence end surface. An emission surface of the guide plate may provide a light control surface, in which a pair of slopes of each projection thereof may be provided with different inclination angles in a similar fashion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.