METHOD FOR WRITING SERVO WRITE TRACK ON DISK, AND DISK DRIVE

PROBLEM TO BE SOLVED: To reduce accumulation of track shape errors by repetition of propagative writing in self-servo write, in which servo data is written to a disk by use of a head, while the head is servo-controlled. SOLUTION: In self-servo write, the accumulated servo write track shape errors are reduced by adding a correction signal to a servo system. The SSW uses a sine wave as a correction signal for servo control. The SSW measures a phase of the sine wave component in the track shape error, and according to the measurement result, determines the phase of the correction sine wave signal to reduce the accumulated track shape error. Thereby, the accumulation of the track shape errors can be suppressed with a simple configuration. COPYRIGHT: (C)2011,JPO&INPIT