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. 16, 2013
Filed:
Mar. 23, 2012
Tsuyoshi Wakazono, Utsunomiya, JP;
Fumiaki Usui, Utsunomiya, JP;
Tsuyoshi Wakazono, Utsunomiya, JP;
Fumiaki Usui, Utsunomiya, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
A zoom lens includes, in order from object side: a positive first lens unit which does not move for zooming; a zoom lens unit including at least two lens units which move for zooming; a stop; and a positive imaging lens unit which does not move for zooming, in which: the first lens unit includes, in order from object side, a positive first sub-lens unit, a negative second sub-lens unit, and a positive third sub-lens unit; the third sub-lens unit includes a movable positive sub-third sub-lens unit; the second sub-lens unit and sub-third sub-lens unit are driven to object side for focusing to a close object; and focal length f12 of the second sub-lens unit, focal length f13f of the sub-third sub-lens unit, drive amount δ×12 of the second sub-lens unit in focusing, and drive amount δ×13f of the sub-third sub-lens unit in focusing satisfy −2.5<f12/f13f<−0.4 and 0.05<δ×13f/δ×12<5.0.