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. 01, 2009
Filed:
Apr. 30, 2008
Atsujiro Ishii, Shibuya-ku, JP;
Atsujiro Ishii, Shibuya-ku, JP;
Olympus Imaging Corp., Tokyo, JP;
Abstract
The invention relates to a zoom lens that can achieve higher performance easily. In order from the object side of the zoom lens, it comprises a positive first lens group G, a negative second lens group G, a positive third lens group Gand a positive fourth lens group G, wherein zooming is implemented by a change in the space between the respective lens groups. Upon zooming from the wide-angle end to the telephoto end, while the space between the first lens group Gand the second lens group Ggrows wide, the space between the second lens group Gand the third lens group Gbecomes narrow and the space between the third lens group Gand the fourth lens group Gbecomes narrow, the first, the third, and the fourth lens group moves toward the object side only, and the second lens group Gmoves in a convex orbit toward the image plane side. The second lens group G, and the fourth lens group Ghas at least one aspheric surface, and the zoom lens satisfies the following conditions: 0.1<|f/f|<0.14 and 0.1<|f/f|<0.6 where fi is the focal length of an i-th lens group.