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, 1985
Filed:
Oct. 12, 1982
Edward J Brooks, Rochester, NY (US);
Carl N Schauffele, Rochester, NY (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
Exposure control apparatus adapted for use with a computer having an inexpensive, uncalibrated clock includes a pair of covariant, internal reference signal sources, an integrator and a comparator that produces a time interval signal when an electrical parameter of the integrator reaches a threshold level established by the comparator. With the covariant reference signal sources connected to the integrator, the computer calculates an initial clock correction factor that is stored in the computer's memory. A standard light source of known intensity, which is used only once, is then coupled to the integrator through a photoresponsive device and the initial clock correction factor is used by the computer to provide compensation for the computer clock during an exposure operation. In the field, the computer, prior to each exposure operation, connects the covariant reference signal sources to the integrator and calculates an updated clock correction factor. When the apparatus is measuring luminance of unknown intensity, for example ambient light, the updated clock correction factor is used by the computer to control a desired exposure parameter.