Test pattern projector for a color television camera
US4682214A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 1986 |
| Grant date | Jul 21, 1987 |
| Priority date | — |
| Expiry date | Jun 12, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N17/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A test pattern projector built into a color television camera, for adjusting the camera to desired conditions in order to attain a favorable quality of image immediately before use. A test pattern chart is illuminated with an illuminating light of an adjusted color temperature, forming an image of the test pattern chart on an image pickup apparatus. The color temperature adjustment of illuminating light emitted from a light source is effected by using a color temperature conversion filter and a color compensating filter both disposed in front of the light source. An interference filter or an absorbing filter with a wedge shape in cross section can be employed as the color compensating filter. The color correction depends, in the former, on the inclination thereof relative to the optical axis and, in the latter, on the thickness thereof intersecting the optical path.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.