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:
Feb. 26, 2008
Filed:
Jul. 09, 2004
Francis K. King, San Jose, CA (US);
Jeffrey Liu, San Jose, CA (US);
Francis K. King, San Jose, CA (US);
Jeffrey Liu, San Jose, CA (US);
Dcard, Inc., Milpitas, CA (US);
Abstract
The invention pertains to an improvement for a tracking and focusing servo and defect management circuit that controls the tracking and focusing of an optical head on an optical media in an apparatus for reproducing a data, sound or image recorded on the optical media. The invention characterizes by the provision of a circuit for managing modulation of an RF signal from the optical pickup head caused when the optical pickup head encounters a non-continuous track in segment arrangement or a very long extended defect such as a extended flaw in the disc resulted discontinuous track segment thereon, and an adjusting circuit which manages the loop gain of the tracking servo circuit per the track arrangement of defect detection and a tracking profile, whereby the responsiveness of the optical pickup head is improved and track skipping prevented or recovered.