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:
Aug. 22, 1995
Filed:
Mar. 24, 1993
Takatoshi Okumura, Hamamatsu, JP;
Yamaha Corporation, , JP;
Abstract
In a method and a device for accessing an optical disc such as a Compact Disc, a CD-ROM, a CD-I and a MD, an optical disc in which data is recorded or to be recorded at a constant linear velocity is rotated at a substantially constant number of revolution per unit time and this optical disc is accessed on the basis of a clock signal which changes its frequency in accordance with an access position (i.e., a read position or write position). Since random accessing is made in a state in which the optical disc is rotated at a substantially constant number of revolution per unit time, it is not necessary to wait in accessing until a stable revolution number is attained but the waiting time is determined only by time required for moving of the read head. This enables the waiting time to be reduced and thereby realizes accessing to the optical disc at a higher speed.