Optical projection apparatus, transmission type screen, and projection type image display apparatus
US6573950B1 · kind B1 · utility
25Cited by
13References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 18, 2000 |
| Grant date | Jun 3, 2003 |
| Priority date | — |
| Expiry date | Jan 18, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/7441
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A single-panel liquid crystal rear side projection type image display apparatus, which is compact in size and can satisfy requirements of both brightness and color purity and can focus images very sharply with the contrast property improved significantly and with less screen distortion, and a projection lens unit comprising three lens groups of about F1.5, which is composed so as to cool the video generator with a cooling liquid and is provided with first to third dichroic mirrors DM1, DM2, and DM3 for separating a white light into the three primary colors in order of red, blue, and green.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.