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:
Dec. 16, 2008
Filed:
May. 30, 2007
Koji Hoshi, Yokohama, JP;
Koji Hoshi, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens includes: a first lens unit of positive refractive power; a second lens unit of negative refractive power; a third lens unit of positive refractive power; and a fourth lens unit of positive refractive power, being disposed in that order from an object side to an image side, in which the second and fourth lens units are moved in a direction parallel with an optical axis of the zoom lens during zooming, the first lens unit consists of one negative lens and three or fewer positive lenses, being disposed in that order from the object side to the image side, and the following condition is satisfied:25.1<1/2<4.1×where BD1 and BD2 are lengths of the first and second lens units along the optical axis, and Z is a zoom ratio.