Surface light source device with polarization function
US5982540A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 13, 1995 |
| Grant date | Nov 9, 1999 |
| Priority date | — |
| Expiry date | Mar 13, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S385/901
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Light is supplied into a light incident surface 2 from a fluorescent lamp L enclosed by a silver foil sheet R, and parallelized illuminating light flux is taken out from a light exit surface 3. On a back surface 4 side of a light flux parallelizer 1, across or without a thin air layer 5, a polarization converter .EPSILON. is disposed. The polarization converter .EPSILON. reinforces the polarization function of the surface light source device through polarization conversion action accompanying reflection in the prism. At a position confronting the light exit surface 3 across an air layer 7, a polarization separating plate 8 is disposed. At a further outside, across an air layer 9, an exit light direction modifier 10 is disposed. A bright polarized illuminating light flux is emitted from a light exit surface 11. When applied to a backlight of a liquid crystal display, a liquid crystal display panel is disposed at a further outside of the exit light direction modifier 10.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.