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. 18, 2001
Filed:
Mar. 05, 1999
Applicant:
Inventor:
Osamu Kasono, Saitama-ken, JP;
Assignee:
Pioneer Electronic Corporation, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G11B 7/12 ;
U.S. Cl.
CPC ...
G11B 7/12 ;
Abstract
An optical head apparatus includes an object lens, a solid immersion lens, drive unit, and control unit. The object lens converges light, which is radiated on a recording surface of a recording media. The solid immersion lens further converges the light having been converged by the object lens. The drive unit drives the object lens along an optical axis. The control unit controls the drive unit so that the distance between the object lens and the solid immersion lens along the optical axis is kept constant, according to reflected light from the solid immersion lens.