Patent ID: 7342735
Filing Date: 2008-03-11
Classification: G11B

Abstract:
1. A method of writing a plurality of aligned patterns onto a rotary recording disk of a data storage device at on-track positions aligned in the circumferential direction of the recording disk by using an internal head having read and write elements provided at positions separated from each other in the radial direction of the recording disk, the method comprising: writing first reference patterns onto a first track; writing second reference patterns onto a second track different from the first track; measuring time intervals between the first reference patterns and the second reference patterns; writing each of first aligned patterns onto another track with the read element positioned on the first track to detect the first reference patterns after the lapse of a first write time period since detection of a corresponding one of the first reference patterns; and writing each of second aligned patterns onto a further track at an on-track position aligned to an on-track position of the corresponding first aligned pattern in the circumferential direction with the read element positioned on the second track to detect the second reference patterns after the lapse of a second write time period since detection of a corresponding one of the second reference patterns; wherein a difference between the first write time period and the second write time period is determined on the basis of the measured time intervals between the first reference patterns and the second reference patterns.