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:
Jun. 29, 2004
Filed:
Mar. 09, 2001
Eiji Kumagai, Shinagawa-Ku, JP;
Kenji Nagashima, Shinagawa-Ku, JP;
Toshio Morizumi, Shinagawa-Ku, JP;
Sony Corporation, Tokyo, JP;
Abstract
An optical recording/reproducing apparatus having drive means for rotating a recording medium, an optical head for applying light to the recording medium being rotated by the drive means, thereby to record data signals on the recording medium or reproducing data from the recording medium, and a signal-processing circuit for processing a signal detected by the optical head. The optical head comprises a light source for emitting light, an objective lens, and signal detecting means. The objective lens has a numerical aperture NA, where 0.5<NA≦0.6. The apparatus can reliably record data on and reproduce data from high-density optical recording media that have different track pitches.