Patent ID: 7023648
Filing Date: 2006-04-04
Classification: G11B

Abstract:
1. A disk drive comprising: a head which records or reproduces data including one or both of a basic servo pattern and a new servo pattern with respect to a disk medium having a disk surface on which the basic servo pattern is recorded in advance, the head including a read head element which reproduces the data and a write head element which records the data; a positioning control unit which positions the head at a target position on the disk medium in accordance with one of the basic servo pattern and the new servo pattern reproduced by the head; an obtaining unit which obtains an offset value according to track position information of the basic servo pattern reproduced by the head at the target position, the offset value being a positional error between a reference position from a rotation center of the disk medium and an actual position from a rotation center of tracks formed based on the basic servo pattern; and a servo write unit which writes the new servo pattern on the disk medium with the head by using the track position information and the offset value.