Extended range exposure control system
US4045806A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 23, 1976 |
| Grant date | Aug 30, 1977 |
| Priority date | — |
| Expiry date | Aug 23, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B7/083
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An extended range exposure control system for photographic cameras having an aperture plate slidably movable from a first position in which it stops down the maximum relative aperture of the camera lens to second and third positions in which a photographic circuit is altered while the maximum relative lens aperture is maintained. A shutter mechanism controlled by a light sensitive circuit includes a switch actuated by movement of the aperture plate to the third position to shift the light level sensitivity range of the circuit thereby accommodating shutter speeds necessary to effect exposure of relatively fast film at maximum relative lens aperture. The aperture plate is slidably supported within a housing for the shutter and the respective positions thereof made clearly visible as a result of indicia on the exterior of the housing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.