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:
Sep. 25, 2012
Filed:
Dec. 20, 2011
Applicant:
Mitsuru Ito, Ibaraki, JP;
Inventor:
Mitsuru Ito, Ibaraki, JP;
Assignee:
Hitachi Maxell, Ltd., Ibaraki-Shi, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 7/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
An optical pickup lens for focusing a light beam from a laser light source on an optical information recording medium is a single lens. The optical pickup lens has two surfaces, and a surface Ropposite to a surface Rcloser to the laser light source has a continuous shape. When the surface Rhas radii h, hand h(h<h<h) from an optical axis to a lens periphery, and where sags in the radii h, hand hare sag, sagand sag, and differentials in the sags are Δsag, Δsagand Δsag, respectively, 0>Δsag>Δsagand Δsag<Δsagare satisfied.