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:
Apr. 28, 2015
Filed:
Nov. 02, 2012
Nikon Corporation, Tokyo, JP;
Daisaku Arai, Tokyo, JP;
Nikon Corporation, Tokyo, JP;
Abstract
Provided is a zoom lens, including, in order from an object: a first lens group (G) having positive refractive power; a second lens group (G) having negative refractive power; a third lens group (G) having positive refractive power; and a fourth lens group (G) having positive refractive power. The first lens group (Gincludes only, in order from the object, a cemented lens of a negative lens (L) and a positive lens (L), and a positive meniscus lens (L) having a convex surface facing the object, an aperture stop (S) for determining brightness is disposed to the object side of the third lens group (G), and upon zooming, all of the four groups (Gto G) move and the aperture stop (S) moves together with the third lens group (G), and the conditional expression νdp1>85.0 is satisfied, where νdp1 denotes an Abbe number of the positive lens (L), which is disposed closest to the object in the first lens group (G), at the d-line as a standard.