Patent ID: 7843658

Claim:
A method of measuring a magnetic write width, comprising the steps of: forming a data track on a discrete track medium by performing a write operation at a first frequency, using a write pole of a magnetic head; performing, using said write pole, write operations at a second frequency that is different from said first frequency, at both side positions along the formed data track, said both side positions being separated from the center of the formed data track by a predetermined distance; obtaining a track profile by scanning said data track in a track-width direction, using a magnetic field detection element; calculating an integrated profile of the obtained track profile; obtaining profile integrals by setting a distance from said data track to a position of the write operations at the second frequency to various values and by calculating the profile integrals for the respective values of the distance; and calculating a magnetic write width of said magnetic head and a magnetic write width of said discrete track medium from a relationship between said distance and said profile integrals.