Light valve for use in a color display unit with a diffraction grating assembly included in the valve
US4751509A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 3, 1986 |
| Grant date | Jun 14, 1988 |
| Priority date | — |
| Expiry date | Jun 3, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2201/305
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a display unit for use in projecting projection light onto a screen to display a picture, a light valve comprises a diffraction grating assembly for selecting one of chrominance components included in an incident light given through one surface of the light valve. The diffraction grating assembly is divided into a plurality of grating elements arranged to give different colors corresponding to the chrominance components. In addition, a control beam, such as a laser, is incident onto the other surface of the light valve to selectively scan the grating elements and to heat selected ones of the grating elements through an energy converting film. Thus, the incident light is subjected to modulation on the grating elements in accordance with heat energy and emitted through a liquid crystal as controlled light from the light valve. The controlled light is sent as the projection light to the screen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.