Reflecting optical system for projection television
US4234894A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 1978 |
| Grant date | Nov 18, 1980 |
| Priority date | — |
| Expiry date | Oct 26, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/31
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A projection television system having a light emitting target and a screen for realizing a projected video image is provided with an improved reflecting optical system which provides enhanced resolution and uniform correction of aberrations across a projected image. The optical system includes a concave mirror, positioned adjacent the light emitting target, for reflecting the video image towards the display screen. An optical compensating plate having at least one aspherical surface is located on the optical path. A meniscus lens is also located in the optical path. Both the optical compensating member and the meniscus lens can be positioned outside the vacuum envelope of the target and the electron gun to simplify alignment and construction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.