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:
May. 25, 2010
Filed:
Sep. 25, 2007
Kenichi Sato, Saitama, JP;
Kenichi Sato, Saitama, JP;
Fujinon Corporation, Saitama-shi, JP;
Abstract
A configuration where a first group having a positive refractive power and a positive second group having a positive refractive power are placed sequentially from the object side is basically used. As the first group, a wide-angle first group and a telephoto first group are selectively switched over to be placed on the optical axis, thereby switching over the focal length between the wide-angle side and the telephoto side. Since the configuration in which the first group placed on the object side is switched is employed, adherence of dust or the like to the imaging surface due to the switching of the focal length can be prevented from occurring. Each group is configured by a minimum number of lenses. The whole system has a configuration which has a reduced number of lenses, and which is small and simple.