The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 30, 1977
Filed:
Aug. 23, 1976
Seymour Ellin, Brookline, MA (US);
John R Sharp, Squantum, MA (US);
Polaroid Corporation, Cambridge, MA (US);
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.