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. 25, 2014
Filed:
May. 23, 2012
Makoto Kanai, Tokyo, JP;
Makoto Kanai, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
A zoom lens comprises, in order from the object side: a first lens group that has a positive refractive power; a second lens group that has a negative refractive power; and a third lens group that has a positive refractive power. Zooming is performed by changing spaces between the first to third lens groups during zooming from a wide-angle end to a telephoto end. The third lens group includes, in order from the object side, a positive lens group, having a positive refractive power, and a negative lens group, disposed to be close to the image side thereof and having a negative refractive power, with an air gap, which is widest in the third lens group, interposed therebetween. The third lens group satisfies the condition −0.45<fGF/fGR<−0.10, where fGF is a focal length of the positive lens group, and fGR is a focal length of the negative lens group.