| 摘要 |
PROBLEM TO BE SOLVED: To obtain a track eccentricity detecting method by which eccentricity quantity and an eccentricity direction of a track of especially a high order are detected in DTM without referring to a servo pattern. SOLUTION: The track eccentricity detecting method includes: a step in which the prescribed data is written in the prescribed region while a head is moved to DTM stepwise in the radius direction; a step in which the data written in the prescribed region while moving the magnetic head in an eccentricity orbit by a plurality of amplitude and phases is read out and a plurality of envelope data are obtained, and smoothness of the obtained plurality of envelope data waveforms is discriminated and a first order eccentricity following orbit in which eccentricity can be detected in the next stage is searched; and a step in which, in a state where the magnetic head follows the first eccentricity based on the first order eccentricity following orbit, data is read out from the prescribed region moving a magnetic head position stepwise in the radius direction to obtain multi-phase envelope data, and a track decimal values of respective sectors are calculated from the obtained multi-phase envelope data, and they are connected successively for each sector to reconstitute an eccentricity form. COPYRIGHT: (C)2009,JPO&INPIT
|
