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. 17, 2018
Filed:
Jul. 31, 2015
Canon Kabushiki Kaisha, Tokyo, JP;
Toyokatsu Fujisaki, Utsunomiya, JP;
Hiroshi Saruwatari, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens includes, in order from an object side to an image side, a first lens unit having positive refractive power, a second lens unit having negative refractive power, a third lens unit having positive refractive power, and a rear lens group including a lens unit having negative refractive power arranged along an optical axis thereof. A focal length fw of the zoom lens at a wide-angle end, a focal length ft of the zoom lens at a telephoto end, an amount of movement Mof the first lens unit on the optical axis in zooming from the wide-angle end to the telephoto end, and a focal length frn of a lens unit Lrn that is a lens unit having a shortest focal length among lens units having negative refractive power included in the rear lens group are appropriately set based on predetermined mathematical conditions.