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:
May. 01, 2012
Filed:
May. 26, 2010
Toyokatsu Fujisaki, Utsunomiya, JP;
Toyokatsu Fujisaki, Utsunomiya, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
A zoom lens comprises a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, a third lens unit having a positive refractive power, and a rear group including at least one lens unit, in order from an object side to an image side. Each of the lens units is configured to move so that a total lens length at a wide-angle end is longer than that at a telephoto end to perform a zoom operation. A movement amount Mof the first lens unit at the wide-angle end and the telephoto end with respect to an imaging surface, a focal length f1 of the first lens unit, and focal lengths fw and ft of a whole system at the wide-angle end and the telephoto end are appropriately set.