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. 14, 1989
Filed:
May. 05, 1988
Hitoshi Mukaiya, Saitama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens comprising, from front to rear, a first lens unit of positive power for focusing, a second lens unit of negative power as the variator, a third lens unit of negative power as the compensator, an afocal fourth lens of positive power, and a fifth lens unit for image formation, the fifth lens unit including, from front to rear, a bi-convex first lens whose front surface is of stronger curvature, a negative meniscus second lens of forward concavity, a positive third lens whose front surface is of stronger curvature, a negative meniscus fourth lens of forward convexity, a bi-convex fifth lens whose rear surface is of stronger curvature, and a positive sixth lens whose front surface is of stronger curvature, wherein the following conditions are satisfied: