Patent ID: 7768737

Claim:
A servo information writing method for writing servo information in a magnetic disk, comprising the steps of positioning a magnetic head in each of a plurality of servo information write positions by moving the magnetic head to an aimed track by a coarse movement stage and to a plurality of servo information write positions in the aimed track by a fine movement stage, writing a plurality of servo information in each of the servo information write positions and similarly a plurality of servo information for a predetermined number of tracks from the aimed track in the respective servo information write positions of a magnetic disk, moving the magnetic head to a next aimed track for every predetermined number of tracks by the coarse movement stage and writing a plurality of servo information in each of a number of tracks of the magnetic disk, wherein a predetermined information is written in an area which is on a circumference of the magnetic disk corresponding to one of a plurality of servo information write positions in a last track or a track, which is one or two in front of the last track, of a predetermined number of tracks and in which servo information is not written, the predetermined information is detected by moving the magnetic head in a radial direction of the magnetic disk by the fine movement stage after the magnetic head is moved to a next aimed track by the coarse movement stage, and the servo information is written for the next aimed track using the radial position of the magnetic head, in which the predetermined information is detected, as a reference.