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:
Apr. 05, 1977
Filed:
Aug. 14, 1975
Ryusho Hirose, Machida, JA;
Canon Kabushiki Kaisha, Tokyo, JA;
Abstract
A zoom lens system wherein the distance between the rearmost lens surface in the afocal zooming lens portion and the foremost lens surface in the image forming lens system is kept unchanged and an afocal magnification varying lens is inserted into the above described distance so as to enlarge the telefoto range, the magnification varying lens consisting of a front convergent lens group and a rear divergent lens group. The requirements for the magnification varying lens are so set that compensation for aberrations is kept in superior condition when zooming is effected by the lens system with the magnification varying lens being eliminated therefrom, while, when zooming is effected under the condition the magnification varying lens is added to the lens system, the aberrations are also well compensated for.