Patent ID: 8593750
Filing Date: 2013-11-26
Classification: G11B

Abstract:
1. An information storage device, comprising: a magnetic storage medium comprising a magnetic recording layer comprising two preamble areas and a re-sync mark area, a plurality of magnetic bodies being in the preamble areas with a plurality of arrangements, the re-sync mark area being at a head of the preamble areas and indicating a start of the preamble areas; a magnetic head configured to read data from to the magnetic storage medium and to write data to the magnetic storage medium; a phase difference detector configured to receive signals from the preamble areas read by the magnetic head, and to detect a phase difference from the readout signals of the preamble areas; a displacement calculator configured to calculate a displacement of the magnetic head with respect to a track center based on the detected phase difference of the readout signals ; and a positioning module configured to control a position of the magnetic head in order to position the magnetic head at the track center based on the displacement of the magnetic head with respect to the track center.