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:
Jan. 12, 2010
Filed:
Aug. 23, 2007
Kohji Takasaki, Kanagawa, JP;
Fuminori Sai, Kanagawa, JP;
Kei Yasuna, Kanagawa, JP;
Tomoyuki Oyama, Kanagawa, JP;
Satoshi Yamamoto, San Jose, CA (US);
Kohji Takasaki, Kanagawa, JP;
Fuminori Sai, Kanagawa, JP;
Kei Yasuna, Kanagawa, JP;
Tomoyuki Oyama, Kanagawa, JP;
Satoshi Yamamoto, San Jose, CA (US);
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
Embodiments of the present invention efficiently perform servo correction for prevention of propagation of a position error in a radial direction in self servo write (SSW). According to one embodiment, in SSW, a target position of a reference track TO in writing a servo write track TN is corrected. The target position is represented as a target value of a position signal calculated from a signal read by a read element. A signal indicating a deviation (a position error) from the target position (the target value) is referred to as PES. The SSW in this example performs correction of target positions in respective tracks using an impulse response of a servo system. Consequently, it is possible to efficiently and effectively prevent the propagation of position error in the SSW.