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. 26, 2006
Filed:
Mar. 05, 2001
Junsaku Nakajima, Kashihara, JP;
Hitoshi Takeuchi, Kitakatsuragi-gun, JP;
Masaru Nomura, Nabari, JP;
Kenji Ohta, Kitakatsuragi-gun, JP;
Junsaku Nakajima, Kashihara, JP;
Hitoshi Takeuchi, Kitakatsuragi-gun, JP;
Masaru Nomura, Nabari, JP;
Kenji Ohta, Kitakatsuragi-gun, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
On an optical disk, a string of a plurality of pits having two different depths is formed. Quantity of light reflected from the pit string is detected by a photoreceptor element, and based on the detected quantity of reflected light, a pit depth detecting unit detects depth of each pit. Based on the detected quantity of reflected light, a servo signal generating unit generates a tracking servo signal. An output control unit supplies the generated tracking servo signal when a pit of such depth that is to be reproduced is tracked, and holds and supplies an immediately preceding tracking servo signal when a pit of different depth is being tracked, based on the result of detection by the pit depth detecting unit.