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. 23, 2010
Filed:
Dec. 23, 2008
Hiroshi Yamamoto, Kawasaki, JP;
Tomoki Ito, Kawasaki, JP;
Satoshi Yamaguchi, Sagamihara, JP;
Atsushi Shibayama, Tokyo, JP;
Hiroshi Yamamoto, Kawasaki, JP;
Tomoki Ito, Kawasaki, JP;
Satoshi Yamaguchi, Sagamihara, JP;
Atsushi Shibayama, Tokyo, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A zoom optical system has a first lens group having a positive refracting power; a second lens group having a negative refracting power; a third lens group having a positive refracting power; a fourth lens group having a negative refracting power; and a fifth lens group having a positive refracting power, in the order from the object side. The fourth lens group is composed of a cemented lens of a negative lens and a positive lens in the order from the object side, and a condition of the following expression is satisfied: νp>30.0, where νp is an Abbe number of the positive lens.