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:
Aug. 23, 2011
Filed:
Aug. 11, 2009
Miho Matsumoto, Tokyo, JP;
Akiko Miyakawa, Sagamihara, JP;
Toshihiko Kurata, Yamato, JP;
Nikon Vision Co., Ltd., Tokyo, JP;
Abstract
An achromatic lens system is provided with a cemented resin lens having positive refractive power constructed by a resin lens Lhaving positive refractive power cemented with a resin lens Lhaving negative refractive power, and a close-contact multi-layer type diffractive optical element LE, the diffractive optical element LE being disposed to an image side of the cemented resin lens, the diffractive optical element LE being constructed by cementing two diffractive element members DE, DEeach made of different optical materials with each other, and the cemented surface thereof being a diffractive optical surface Gf on which grooves of a diffraction grating are formed, there by being lightweight and easily manufactured, capable of excellently correcting chromatic aberration and spherical aberration at the same time.