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:
Sep. 21, 2010
Filed:
May. 04, 2009
Isamu Izuhara, Osaka, JP;
Hiromichi Nose, Tokyo, JP;
Isamu Izuhara, Osaka, JP;
Hiromichi Nose, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
A zoom lens includes a first lens group having negative refractive power and a second lens group having positive refractive power, each including at least one plastic aspherical lens. The zoom lens satisfies the following Conditional Expressions (1) and (2), (1) 0.40<fw/bkw<0.60; (2) 0.01<|(X1−X0)/h0|<0.022, where fw: focal length of the entire zoom lens in focus at infinity in a wide-angle end state; bkw: back focus when the entire zoom lens is in focus at infinity in the wide-angle end state; X1: thickness at an image-side effective diameter position of the plastic aspherical lens of the first lens group; X0: thickness at the center of the plastic aspherical lens of the first lens group; and h0: image-side effective radius of the plastic aspherical lens of the first lens group.