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:
Jul. 10, 2007
Filed:
Jul. 28, 2005
Shuhsuke Kurihara, Kanagawa, JP;
Kenji Ogasawara, Kanagawa, JP;
Yuhji Takagi, Kanagawa, JP;
Hiroshi Uchiike, Kanagawa, JP;
Shuhsuke Kurihara, Kanagawa, JP;
Kenji Ogasawara, Kanagawa, JP;
Yuhji Takagi, Kanagawa, JP;
Hiroshi Uchiike, Kanagawa, JP;
HItachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
Embodiments of the invention provide techniques to inspect the track pitch of a magnetic disk. In one embodiment, the track pitch is inspected using the servo information that was written onto the magnetic disk. A PES gain is set to be PGA head is moved to a position K near the position where control is to switch between MPES and SPES, and then MPES and SPES are calculated using reproduced burst signals and PGThe quantity of change in the inspection HSP which is a half-servo pitch of an inspection-related burst pattern, with respect to an ideal half-servo pitch, is detected by calculating PESΔ, the difference between the MPES and SPES at position K. The track pitch is thus judged whether it is abnormal.