An Investigation of Slider Vibrations in Near Contact Recording Using a Digital Laser Doppler Vibrometer

Abstract

At a flying height of 10 nanometers, contacts between slider and disk are likely to occur, and control of contact-induced slider vibrations is an important design consideration. In this study, slider vibrations during contact are investigated using a digital laser Doppler vibrometer (LDV). The noise level of the digital interferometer is compared with that of a conventional analog LDV. In addition, acoustic emission (AE) sensors are used to evaluate the contact behavior of the slider. A comparison of AE and LDV data is performed. The results show that the noise level of the digital LDV is lower than that of the analog LDV, and that suspension sway mode vibrations and torsion mode vibrations are excited during contact as a function of the skew angle.