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. 08, 2009
Filed:
Dec. 20, 2007
Kazunori Ohno, Saitama, JP;
Kazunori Ohno, Saitama, JP;
Fujinon Corporation, Saitama-shi, JP;
Abstract
To provide a lens system advantageous for downsizing a moving group and suitable for large aperture ratio formation and ultra telescopic formation while maintaining an excellent optical function from a long distance to a close range. 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, and a fourth lens group having a negative refracting power are provided in order from an object side. The first lens group includes a first sub group and a second sub group. The second sub group is provided with a refracting power stronger than that of the first sub group and a following condition equation is satisfied.1.5<11<2.2  (1)