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:
Mar. 05, 1991
Filed:
Sep. 29, 1989
Judith N Coltman, Reading, MA (US);
John P Gaewsky, Reading, MA (US);
Jeffrey T Gray, Boston, MA (US);
Polaroid Corporation, Cambridge, MA (US);
Abstract
An automatic exposure system for an electronic flash camera incorporates an arrangement for measuring the reflectivity of a scene illuminated by the electronic flash prior to exposure in order to determine certain photographic scene characteristics for use in controlling a subsequent photographic exposure, an arrangement that substantially reduces the complexity and energy consumption of the electronic flash system while improving the ability of the exposure control system to accurately determine these characteristics. The arrangement includes the pre-exposure firing of the electronic flash to illuminate a scene with a pulse of light for a short, fixed period of time. A reflection of this light pulse is integrated for a portion of this fixed period of time. The final integrated value of the reflected light is a measure of subject reflectivity. This integrated value is then employed to derive the desired photographic scene characteristics.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile