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. 11, 2012
Filed:
Mar. 02, 2011
Masaru Eguchi, Saitama, JP;
Masaru Eguchi, Saitama, JP;
Hoya Corporation, Tokyo, JP;
Abstract
A high zoom-ratio zoom lens system includes a positive first lens group, a negative second lens group, a positive third lens group, and a positive fourth lens group, in that order from the object side. Upon zooming from the short to long focal length extremities, at least the first through third lens groups are moved along the optical axis direction, wherein an amount of movement of the first lens group is greater than that of the third lens group. The following conditions (1), (2) and (3) are satisfied:0.9<1<2  (1),3<1/<7  (2), and−8<1/2<−5  (3),wherein FT and FW designate the entire focal length of the zoom lens system at the long and short focal length extremities, respectively; and F1 and F2 designate the focal length of the first and second lens groups, respectively.