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:
Oct. 27, 1998
Filed:
May. 19, 1997
Yasuo Nagai, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
A multi-head disk recording and reproducing apparatus, wherein sector synchronization signals obtained from a first optical pick-up and a second optical pick-up are input to a phase comparator where phases are compared, and a preceding sector synchronization signal is output to an overall control unit. In the overall control unit, the processing is carried out with respect to a first optical pick-up and second optical pick-up by a procedure using this input preceding sector synchronization signal as a reference. First, during a term where addresses are determined in the pick-ups, a sled servo and a spindle servo operation are carried out with respect to each pick-up. When the maximum time t of phase deviation has elapsed and addresses are determined, a tracking servo, focus servo, laser control, and other operations are instructed to the control units based on the addresses.