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:
Nov. 05, 1991
Filed:
Dec. 05, 1989
Norio Nishida, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
Apparatus for detecting the speed with which a light beam emitted by an optical head accesses a target record track on an optical disc in which record track traverse data indicating track number are recorded previously. The traverse data is read and traverse data signals indicative of the scanning position of the light beam are produced. Deviations in the traverse data signals obtained at predetermined time intervals are detected to form upper order data bits representing access speed. At the same time, tracking error data signals proportionate to the deviation of the light beam from a record track on the disc are produced and a deviation in the tracking error data signals is detected to form the lower data bits of the access speed.