Surface light source device
US8920017B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 2013 |
| Grant date | Dec 30, 2014 |
| Priority date | — |
| Expiry date | Mar 1, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/002
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A variation in luminance is reduced near a light source without decreasing intensity of a light exit pattern. A light source is disposed and a light exit pattern is formed. The light exit pattern reflects light guided in a light guide plate and outputs the light. In inclined angles of tangents of the light exit patterns in a section passing through a center axis of the light exit pattern, a largest inclined angle of the tangent is defined as a maximum inclined angle of the light exit pattern. At this time, in the light exit pattern provided in the light guide plate, the maximum inclined angle is decreased with increasing distance from a light incident surface in a region near the light incident surface, and the maximum inclined angle is decreased or kept constant with increasing distance from the light incident surface in a region distant from the region near the light incident surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.