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. 02, 1999
Filed:
May. 29, 1997
Fujitsu Limited, Kawasaki, JP;
Abstract
An index determining unit determines that a current position in a disk medium corresponds to a true index when reaching a true index pattern of servo information recorded in the disk medium. The determination is used for reading predetermined servo information so as to perform a servo control operation of a disk reading/writing head. The disk medium has the true index pattern in a first portion of the disk medium and also untrue index patterns of servo information in a predetermined number of second portions in proximity to the first portion along a track direction. The true index pattern and the untrue index patterns form a predetermined sequence. The index determining unit comprises a reading unit for reading the servo information recorded in the disk medium; a storing unit for storing the read servo information in series; and a determining unit for determining that a current position in the disk medium corresponds to the true index when the stored servo information includes a sequence which is different from the predetermined sequence by a predetermined error.