Patent ID: 7787201

Claim:
A method for controlling proximity of a read element of a perpendicular-magnetic-recording head to a perpendicular-magnetic-recording disk, said method comprising: a) writing recorded data with a write element of said perpendicular-magnetic-recording head to said perpendicular-magnetic-recording disk; b) providing a proximity-control setting to a proximity-control element; c) positioning said read element of said perpendicular-magnetic-recording head with said proximity-control element as determined by said proximity-control setting in communication with said perpendicular-magnetic-recording disk for reading said recorded data back from said perpendicular-magnetic-recording disk; d) measuring a resolution of a read-back signal of said recorded data on said perpendicular-magnetic-recording disk associated with said proximity-control setting; e) determining if said resolution measured for said read-back signal of said recorded data on said perpendicular-magnetic-recording disk satisfies a criterion for said resolution of said read-back signal of said recorded data, wherein said resolution is measured by T 50 obtained from said read-back signal of said recorded data written with a low-frequency, square-wave waveform; and f) changing said proximity-control setting, and repeating b), c), d) and e), unless said resolution satisfies said criterion, wherein proximity of said read element is controlled by said resolution of said read-back signal of said recorded data.