Light unit using point light source, and liquid crystal display using the same light unit
US6644824B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 21, 2001 |
| Grant date | Nov 11, 2003 |
| Priority date | — |
| Expiry date | Dec 21, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/0038
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a light unit that converts a false linear light into which a light from a point light source has been converted by a columnar light guide, into a planar light by a plate-shaped light guide, the point light source is arranged only at an end of the columnar light guide at which an angle between a longitudinal direction of the columnar light guide and ridge lines of recesses and projections forming a prism surface is obtuse. Thus, a positional relationship between the point light source and the ridge lines is set so that a main irradiation direction of band-shaped light emitted from the columnar light guide and which has been obtained by converting the light from the point light source to a false linear light is not substantially orthogonal to the ridge lines of the recesses and projections forming the prism surface of the plate-shaped light guide. Consequently, light obtained by totally reflecting this band-shaped light is unlikely to be viewed. Therefore, there is provided a liquid-crystal display having a light unit that eliminates a non-uniformity of luminance even if the angle between the direction in which pixels are arranged on a liquid-crystal panel in a matrix and the ridg…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.