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:
Dec. 12, 1995
Filed:
Mar. 16, 1995
Kazutoshi Shimizume, Kanagawa, JP;
Mamoru Akita, Kanagawa, JP;
Shigeru Inohana, Tokyo, JP;
Hidenobu Noda, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
In a recording and reproducing apparatus of CD or the like, it is adapted such that the time difference between an edge of a PLL clock synchronized with an EFM signal and a transition point of the EFM signal is measured in a time difference measuring circuit, a focus bias voltage to bring the time difference to a minimum is established in a bias voltage generator, the established focus bias voltage is added in an adder to a focus error signal generated in a focus error signal generator, and, thereby, the focus bias is automatically adjusted and focus servo is executed in accordance with the bias-adjusted focus error signal.