| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for evaluating characteristics of a perpendicular magnetic recording medium that is suitable for obtaining a perpendicular magnetic recording medium that is adaptable to increased recording density.SOLUTION: The method for evaluating the perpendicular magnetic recording medium includes: a step for recording a first signal of a specific frequency at an arbitrary first position on the perpendicular magnetic recording medium; a step for measuring a reproduction output of the first signal, and measuring the signal-to-noise ratio (initial value) of the first signal at a peak position at which the reproduction output becomes largest; a step for recording a signal of a specific frequency at a second position separated from the first position by a predetermined distance in the radial direction of the perpendicular magnetic recording medium; a step for measuring again the signal-to-noise ratio of the first signal at the peak position; a step for repeating a step of recording a signal of a specific frequency at a position closer to the first position from the second position by a predetermined distance, and measuring again the signal-to-noise ratio of the first signal at the peak position, while sequentially approaching in the direction of the first position from the second position; and a step of determining whether the value of the signal-to-noise ratio has decreased by a predetermined range or more compared with the initial value. |
