Low profile liquid crystal projector and method of using same
US5321450A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 11, 1993 |
| Grant date | Jun 14, 1994 |
| Priority date | — |
| Expiry date | May 11, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2340/0485
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An liquid crystal unit, and a novel method of us to project a liquid crystal image with substantially no keystoning effects. A low profile projector optics arrangement directs high intensity light within the housing along an irregularly shaped light path extending angularly through an angularly inclined liquid crystal display panel offset by an angle .lambda. relative to the normal axis plane of the display panel to help reduce image keystoning. An output mirror mounted above the housing is inclined angularly opposite to the liquid crystal display panel and cooperates with a lens set for projecting reflectively a liquid crystal image, formed by the display panel, onto a remote surface. The output mirror is mounted to reflect the liquid crystal image upwardly at an angle .theta. to the normal axis plane of the remote viewing surface, where the angle .lambda. and the angle .theta. are substantially equal to help reduce image keystoning. The inventive method of using the liquid crystal projector includes, passing light along an irregularly shaped light path extending angularly through the liquid crystal panel offset by an angle .lambda. relative to the normal axis plane of the display…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.