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:
Feb. 07, 2017
Filed:
Jan. 24, 2015
Nikon Corporation, Chiyoda-ku, Tokyo, JP;
Saburo Masugi, Kawasaki, JP;
Nikon Corporation, Tokyo, JP;
Abstract
The present invention has, in order along the optical axis from the object side: a first lens group (G) that has positive refractive power; a second lens group (G) that has negative refractive power; a third lens group (G) that has positive refractive power; a fourth lens group (G) that has positive refractive power; and a fifth lens group (G). The fourth lens group (G) is constituted by a single positive lens (L), and the fifth lens group (G) is constituted by a single lens (L), which is fixed with respect to an image plane while power is being varied. The following conditional expression (1) is satisfied. 0.9<β2t·β3w/(β2w·β3t)<1.7 . . . (1), where β2w denotes a magnification of the second lens group (G) in the wide-angle end state, β3w denotes a magnification of the third lens group (G) in the wide-angle end state, β2t denotes a magnification of the second lens group (G) in the telephoto end state, and β3t denotes a magnification of the third lens group (G) in the telephoto end state.