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:
Nov. 10, 2009
Filed:
Oct. 22, 2008
Tomonori Kimura, Utsunomiya, JP;
Tomonori Kimura, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens achieves a high zoom ratio and high optical performance in an entire zoom range. The zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a rear unit which includes at least one lens unit. At least the second lens unit is moved during zooming such that a distance between the first and second lens units is larger at a telephoto end than at a wide-angle end. The first lens unit includes at least a first lens element made of a material which satisfies Nd>2.3−0.01·νdand 1.65<Nd<2.70. The first and second lens units satisfy 2.5<|f/f|<12.0.