Projection optical apparatus comprising automatic adjustment unit
US5537168A · kind A · utility
22Cited by
22References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 24, 1994 |
| Grant date | Jul 16, 1996 |
| Priority date | — |
| Expiry date | Oct 24, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/74
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a projection type display apparatus for illuminating a projection original image with light from a projection light source, and projecting light transmitted through the illuminated original image using a projection lens, light reflected by a projection surface is extracted from a position at an original image side of the projection lens or in the projection lens, and the extracted light is received by a focus detection unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.