An investigation of the take-off behavior of proximity recording sliders using acoustic emission and phase demodulated interferometry

The ''take-off'' behavior of proximity recording sliders is investigated using acoustic emission and phase demodulated laser interferometry. A biquadratic surface fit of the air bearing surface is used to determine the position of the slider with respect to the disk. Acoustic emission data is examined in both the time and frequency domain to analyze the location of slider/disk contacts. Two distinct frequencies are observed in the frequency spectrum of the acoustic emission signal, corresponding to torsional mode and bending mode vibrations of the rigid slider. As the velocity increases, the magnitude of the torsional mode decreases relative to that of the bending mode, indicating that slider/disk contacts change from side rails contacts to trailing edge contacts.