Projection display device
US5123729A · kind A · utility
25Cited by
7References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 19, 1991 |
| Grant date | Jun 23, 1992 |
| Priority date | — |
| Expiry date | Apr 19, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/7441
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a projection display device having an illumination optical system which converts the light emitted from a point light source into a substantially parallel luminous flux, a light valve which modulates the light flux, and an optical projection system which projects images on the light valve onto a screen, the illumination optical system converts the light into a substantially parallel luminous flux having a cross section of substantially the same size and shape, e.g., rectangular shape, as the shape of the frame of the light valve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.