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. 16, 1993
Filed:
Oct. 17, 1990
Koji Iwamoto, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
Lens control apparatus for use in a video camera in which an object is imaged through an adjustable lens onto an image pick-up element from which a video signal is derived. The lens is driven for focus or zoom adjustments by servo control at a rate determined by the synchronizing signal included in the video signal. The aperture of the video camera also is controlled by detecting the amount of light which impinges on the image pickup element and then determining the ratio between the detected light level and a reference level representing the brightness of the object. The aperture is driven (i.e. it is enlarged or reduced) as a function of the product of the aforementioned ration and a coefficient which changes with the aperture opening. When the aforementioned ratio is less than unity, the coefficient increases as the aperture opening decreases and, conversely, decreases as the opening increases. When the ratio is greater than unity, the coefficient increases as the aperture opening increases and, conversely, decreases as the opening decreases.