Exposure control system
US4862206A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1988 |
| Grant date | Aug 29, 1989 |
| Priority date | — |
| Expiry date | Apr 26, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B7/28
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A contralight compensation exposure control system which determines as a contralight condition and fires a strobe when there is a difference between the output of a partial light measuring means for measuring the brightness of a portion of a scene to be photographed i.e. the brightness of the main object such as a person, and the output of an average light measuring means for measuring the brightness of comparatively large area of the scene i.e. the brightness of the subordinate object such as the background of the main object. The control circuit of the system inhibits the strobe firing and actuates an exposure compensation means to shift the controlled exposure to the overexposure side when a detecting means detect uncompletion of charging of the main capacitor for firing the strobe even if the contralight condition is detected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.