Surface light source device of side light type
US5810464A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Feb 1, 1996 |
| Grant date | Sep 22, 1998 |
| Priority date | — |
| Expiry date | Feb 1, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/0055
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A surface light source device of side light type controls the intensity of light rays emitted therefrom. The surface light source device of side light type comprises a light scattering guide 20 having a light incidence surface 22, a light emission surface 23 and an inclined surface 25. The device further includes a primary light source L arranged around one side of the light incidence surface 22, a silver foil R surrounding the primary light source L, a prism sheet 4 arranged along the light emission surface 23, and a silver foil S arranged along the inclined surface 25. The inclined surface 25 of the light scattering guide 20 composed of three sections I, II and III. The section I is a convex cylindrical surface section having a radius of curvature of 330 mm. The tangential direction at the end of the guide on the side of the light incidence surface 22 is parallel to the light emission surface 23. The tangential direction at the boundary between the sections I and II is inclined at an angle 4.degree. with respect to the light emission surface 23. The sections II and III are straight sections whose inclinations are 4.degree. and 3.6.degree. with respect to the light emission surfac…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.