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:
Sep. 01, 1992
Filed:
Oct. 25, 1990
Haruhiko Yamanouchi, Kanagawa, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens of the kind varying the focusing movement degree of a focusing-and-zooming lens according to the change of focal length caused by a power varying operation comprises a zooming cam member which rotates around an optical axis in response to zooming; a zoom cam formed in the zooming cam member; a first cam follower which engages the zoom cam; a zooming lens group which is movable in association with the movement of the first cam follower; a focusing cam member; a focus cam formed in the focusing cam member; a second cam follower which engages the focus cam; the focusing-and-zooming lens which is movable in association with the movement of the second cam follower; a focusing rotation member which rotates the second cam follower in response to a focusing action; and a moving mechanism which is arranged to vary the position of the focus cam by moving the focusing cam member in the optical axis direction in response to the rotation of the zooming cam member, in such a manner that a range of engagement of the second cam follower with the focus cam in the focusing action varies and the position of the second cam follower in the optical axis direction varies.