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. 08, 2009
Filed:
Mar. 13, 2008
Kenichi Sato, Saitama, JP;
Kenichi Sato, Saitama, JP;
Fujinon Corporation, Saitama-shi, Saitama, JP;
Abstract
A zoom lens comprises first, second, third and fourth lens groups in order from an object side, so as to change magnification by changing a spacing between the lens groups. The first lens group has a positive refractive power as a whole and comprises, in order from the object side, a negative meniscus lens, a reflecting member that bends an optical path nearly 90 degrees and a positive lens of a resin material having at least one aspheric surface. The second lens group has a negative refractive power as a whole and comprises a negative lens of a resin material on an most object side of the second lens group. A conditional expression given below is satisfied provided that Pis a focal length of the positive lens of the resin material in the first lens group, and Pis a focal length of the negative lens of the resin material in the second lens group.1.0<|1/2|<3.0   (1).