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:
Jul. 17, 2007
Filed:
Mar. 29, 2006
Hideyuki Matsushita, Tochigi, JP;
Keiji Komiya, Tochigi, JP;
Hideyuki Matsushita, Tochigi, JP;
Keiji Komiya, Tochigi, JP;
Fujinon Sano Corporation, Sano-shi, JP;
Abstract
A collimator lens located in a light path from a laser light source to an optical information recording medium. The collimator lens is constituted by a cemented lens which is composed of a biconvex lens and a meniscus lens, and an aspheric plastic lens in the form of a transparent thin synthetic resin film which is laminated on a lens surface of the biconvex lens on the side of or facing toward an optical recording medium. When calculated on the basis of a composite focal length f=10 mm, the collimator lens has an epaxial chromatic aberration correction rate (a) and a numerical aperture NA in the ranges of (1) (a) <2.2 μm/nm and (2) 0.4>NA≧0.12, respectively.