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. 08, 1991
Filed:
Sep. 18, 1989
Isao Hijikata, Yokohama, JP;
Victor Company of Japan, Ltd., Yokohama, JP;
Abstract
In a zoom lens apparatus with auto-focusing comprising a zoom lens; a focus lens; an imaging device; a signal generation circuit responsive to an output of the imaging device for generating a focus signal indicative of in-focus degree of an optical image on the imaging device; and a control circuit responsive to the focus signal and an external signal indicative of zooming the zoom lens for positioning the zoom and focus lens such that the focus lens position is controlled in accordance with a focus voltage when the external signal is not fed and moved in accordance with one of preset characteristic curves showing position relation between the zoom and focus lenses when the external signal is fed, the characteristic curve being selected according to the focus voltage, another characteristic curve is selected from plural characteristic curves in accordance with a difference between the focus voltages before and after moving the zoom lens or moving the focus lens by a given amount when the external signal indicates the zoom lens is to be moved form wide-angle to telephoto position and for sending the selected curve to the control circuit to prevent blurring on a reproduced image.