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:
Mar. 11, 2014
Filed:
Mar. 27, 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 an object side: a first lens unit having positive refractive power which does not move for varying magnification; a magnification-varying lens unit including at least two lens units which move for varying magnification; an aperture stop; and an imaging lens unit having positive refractive power which does not move for varying magnification, in which: the first lens unit includes, in order from the object side, a first sub-lens unit having positive refractive power, a second sub-lens unit having negative refractive power, and a third sub-lens unit having positive refractive power; the second sub-lens unit is driven to the object side so as to perform focus adjustment to an object at a short distance; and the following expression is satisfied: 0.07<f/f<0.35, where frepresents a focal length of the first lens unit, and frepresents a focal length of the first sub-lens unit.