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:
Mar. 17, 2009
Filed:
Aug. 09, 2007
Katsuhisa Tsutsumi, Saitama, JP;
Nobuaki Toyama, Saitama, JP;
Katsuhisa Tsutsumi, Saitama, JP;
Nobuaki Toyama, Saitama, JP;
Fujinon Corporation, Saitama-Shi, JP;
Abstract
A focusing group Gis disposed on an object side relative to a variator group G. The focusing group Gincludes, in order from the object side, a first group Ghaving a positive refractive power, a second group Ghaving a positive refractive power, and a third group Ghaving a positive refractive power. The first group Ghas, in order from the object side, at least one concave lens (L) and at least one convex lens. When focusing from an infinitely distant object to a close object, the second group Gand the third group Gare moved so that with respect to a change in an object distance, an amount of movement of the second group Gbecomes large in a region near infinity, while an amount of movement of the third group Gbecomes large in a close range.