Two-Dimensional Flying-Height Modulation Mapping At Hdd Drive Level

A measurement system for flying-height modulation of magnetic heads is proposed, and two-dimensional flying-height modulation mapping is demonstrated at the Hdd drive level. To write the code for flying-height modulation measurement at the same wavelength, the write frequency should be changed according to the track position, and measured voltage contains an error from the frequency response of the measurement system. The frequency response of the measurement system was calibrated, and measurement accuracy was improved.