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. 27, 2010
Filed:
Oct. 04, 2005
Motoyuki Ohtake, Saitama, JP;
Shinichi Arita, Tokyo, JP;
Motoyuki Ohtake, Saitama, JP;
Shinichi Arita, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
To provide a zoom lens capable of achieving stable optical quality by inhibiting an effect of assemble errors during manufacturing. A zoom lens includes a positive first lens group G, a negative second lens group G, a positive third lens group G, and a positive fourth lens group G, which are arranged from an object side in that order, and during variation in lens position from a wide angle end state to a telescopic end state, Gand Gare fixed, Gis moved toward an image side, Gmoves so as to compensate fluctuations in image-surface position due to the shift of G, and an aperture diaphragm S is fixed adjacent to the object side of G, etc. Gincludes a negative meniscus lens Lwith a concave surface opposing the image side and a cemented lens Lof a biconcave lens and a positive lens with a convex surface opposing the object side, which are arranged from the object side in that order, and the negative meniscus lens is a compound lens of a glass lens and a resin lens PL formed adjacent to the image side of the glass lens, the lens surface adjacent to the image side of the resin lens is aspheric, and the conditional equation (1) below is satisfied:n2>1.75,   (1)where n2 is the average refractive index of glass constituting G