Liquid crystal projector
US4770525A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 1987 |
| Grant date | Sep 13, 1988 |
| Priority date | — |
| Expiry date | Mar 12, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B21/006
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a liquid crystal projector wherein a light source is arranged behind a transmission liquid crystal display panel having a rectangular display portion, an image displayed on the liquid crystal display panel is enlarged by a projection lens, and an enlarged image is projected on the screen located in front of the liquid crystal display panel, a linear Fresnel lens is arranged between the light source and the liquid crystal display panel to narrow illumination light beam from the light source along only the widthwise direction of the rectangular display portion. When the illumination light beam from the light source is narrowed along only the widthwise direction of panel, the amount of unused light beam emitted outside the long sides of the display portion can be reduced, and the light beam from the light source can be effectively utilized for image projection.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.