| 摘要 |
PROBLEM TO BE SOLVED: To provide an evaluation method which can perform evaluation of heat fluctuation characteristics in a comparatively short time, without being accompanied by complicated adjustment work in an evaluation test of heat fluctuation accompanied by acceleration; and to provide an evaluation device for the evaluation method.SOLUTION: The evaluation device monitors reproduction output of a track, while giving a magnetic field to the track, performs operation of finding critical time when average amplitude of reproduction output waveform becomes equal to or lower than a prescribed value with respect to the average amplitude immediately after recording on a magnetic field of a plurality of strengths, computes the critical time when not giving the magnetic field by applying extrapolation to a logarithmic value of the critical time for each magnetic field of the plurality of strengths, and evaluates the heat fluctuation characteristics of the magnetic disk medium by length of the computed critical time. |
