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:
Oct. 25, 1988
Filed:
May. 29, 1987
Thomas C Nutting, Fairport, NY (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
The control computer of a still video camera provides discrete video gain adjustments to the signal processing section during preview operation of an electronic viewfinder. Because exposure time is fixed for preview, and depth of field can be dramatically larger than for still recording, focusing discrepancies can arise between the viewfinder display and the subsequent still recording. This is true especially as light levels are increasing. Discretely varying the video gain has the effect of discretely varying the effective exposure value at the plane of the image sensor. Thus, by lowering video gain during preview for high light levels and concomitantly reducing the exposure value, the viewfinder aperture is driven further open to a value more closely matching the still aperture. As a large aperture means reduced depth of field, focusing errors are reduced.