Patent ID: 7489463

Claim:
A method of writing patterns onto a rotary recording disk mounted on a data storage device by using an internal head employing a read element and a write element having different positions a radial direction of the rotary recording disk, the method comprising: (a) forming pattern arrays, which each comprise a plurality of patterns located on a plurality of adjacent tracks at on-track sector positions aligned in a circumferential direction of the rotary recording disk and are separated from each other in the circumferential direction; (b) measuring time intervals between patterns located at on-track sector positions of two adjacent sectors for every two adjacent sectors on a particular one of the tracks for each of the tracks; (c) determining write timings on the basis of the measured timing intervals; and (d) writing a first servo pattern onto a first servo track different from the tracks with the determined write timing following detection of a pattern written in the first sector of the two adjacent sectors on the particular track.