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:
Jul. 17, 2012
Filed:
Aug. 02, 2010
Tsuyoshi Wakazono, Utsunomiya, JP;
Masao Hori, Utsunomiya, JP;
Tsuyoshi Wakazono, Utsunomiya, JP;
Masao Hori, Utsunomiya, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
A zoom lens including in order from an object side to an image side: a positive first lens unit which does not move for zooming; a negative second lens unit for magnification, and a rear lens group including two or more lens units, in which: the first lens unit includes a first subunit not moving for focusing and a second subunit moving for focusing, and the first subunit includes two or more negative lenses and one or more positive lenses; and an average Abbe number and an average partial dispersion ratio of materials of the negative lenses included in the first subunit, average Abbe number and average partial dispersion ratio of materials of the one or more positive lenses included in the first lens unit, combined focal length of the negative lenses included in the first subunit, and focal length of the zoom lens at telephoto end are appropriately set.