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, 2012
Filed:
Apr. 08, 2005
Kunihiro Shioura, Kanagawa, JP;
Shiro Morotomi, Kanagawa, JP;
Minoru Tobita, Tokyo, JP;
Toshiya Murakami, Kanagawa, JP;
Atsushi Umezawa, Kanagawa, JP;
Kunihiro Shioura, Kanagawa, JP;
Shiro Morotomi, Kanagawa, JP;
Minoru Tobita, Tokyo, JP;
Toshiya Murakami, Kanagawa, JP;
Atsushi Umezawa, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
A reproduction apparatus for an optical recording medium that has a convex pit recording layer, in which pits are formed in a convex shape viewed from a laser incidence side, and a concave pit recording layer, in which pits are formed in a concave shape viewed from the laser incidence side, as recording layers in which data is recorded by pit strings, the pits being formed with a depth that is set in a range of λ/4.5 to λ/6 with respect to a laser wavelength λ, including: an optical head section that irradiates laser beams on the recording layers and detects reflected light information to read out information recorded in the recording layers; a tracking error signal generating section that generates a tracking signal; a polarity switching section that switches a polarity of the tracking error signal; and a tracking servo section that performs a tracking servo operation.