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:
Oct. 21, 2025
Filed:
Aug. 24, 2020
Nikon Corporation, Tokyo, JP;
Mami Muratani, Tokyo, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A variable magnification optical system having a front lens group and a rear lens group arranged in order from the object side along an optical axis, the rear lens group comprising a first focusing lens group and a second focusing lens group. When the magnification is changed, the spacing between lens groups adjacent to each other changes, at the time of changing from focusing on an object at infinity to focusing on an object at a short distance, the position of the front lens group is fixed, the first and second focusing lens groups move to the image surface side along different trajectories, and the conditional expression 0.05<(−fF2)/ft<0.50 is satisfied, where fF2 is the focal length of the second focusing lens group, and ft is the focal length of the variable magnification optical system in a telephoto end state.