Modification of color component video signals to compensate for decreasing white sensitivity of photographic element
US4694356A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 16, 1985 |
| Grant date | Sep 15, 1987 |
| Priority date | — |
| Expiry date | Sep 16, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/84
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A color video printer for producing a color photographic copy from a color video signal. A self-processing color photographic element is exposed to a sequence of six color field images constituting a full frame of a color video image. The printer includes a monochrome cathode-ray-tube (CRT) and a rotatable color filter have red (R), green (G) and blue (B) filters which are sequentially moved into an optical path between the CRT and the photographic element positioned at an exposure station. A video signal circuit provides a color video signal including concurrent R,G,B component signals which are modified with additional gain in the near white region to compensate for the drop off in white sensitivity of the photographic element in this region. A gate is selectively actuated to apply one of the white compensated color component signals to the CRT to effect exposure of the photographic element. Adjustable controls are provided to adjust the relative amount of red, green and blue signal contributing to the photographic exposure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.