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:
Feb. 12, 1980
Filed:
Apr. 21, 1978
Conrad H Biber, Needham, MA (US);
Bruce K Johnson, Andover, MA (US);
George D Whiteside, Lexington, MA (US);
Polaroid Corporation, Cambridge, MA (US);
Abstract
An image recording apparatus and method employing a diaphragm shutter having a time variable exposure aperture with flash firing, following actuation of the shutter, after a time interval dependent on subject range. The functional relationship between the time interval and subject range establishes a parametric relationship between the brightness of the subject due to its flash illumination and the scan time of the diaphragm shutter. The inverse of this parametric relationship constitutes the timewise variation in the exposure aperture area of the shutter. Consequently, whenever the subject is within a predetermined maximum distance from the camera, dependent upon the maximum aperture area attainable by the shutter, the instantaneous product of subject brightness and aperture area will be a constant with the result that proper exposure of the photographic film is achieved independent of the subject range.