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:
Jan. 29, 2013
Filed:
Aug. 25, 2011
Tatsuyuki Onozaki, Tokyo, JP;
Tatsuyuki Onozaki, Tokyo, JP;
Pentax Ricoh Imaging Company, Ltd., Tokyo, JP;
Abstract
A macro lens system includes a positive first lens group, a negative second lens group, a positive third lens group, and a negative fourth lens group, in that order from the object. Upon focusing from an infinite photographic distance to a life-sized photographic distance, the first lens group remains stationary with respect to the imaging plane, and the second and third lens groups move along the optical axis direction. The macro lens system satisfies the following condition: −4.6<f2/fi<−3.0 wherein f2 designates the focal length of the second lens group; and fi the focal length of the entire the macro lens system when an object at infinity is in an in-focus state.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile