Spectrogram analysis of random laser texture pattern media

The application of spectrogram analysis for characterizing random laser texture pattern on magnetic media is explored in this study. Spectrogram analysis of acoustic emission (AE) signals, consisting of identifying multiple AE signal spectra in the time domain, was carried out. The assignment of the signals in the AE spectra of a measured sample facilitated the identification of slider resonances and other excitations in the head–disk interface. The spoke-like lines in the spectrogram are a result of excitation frequencies induced by laser texture patterns. Further AE spectral analysis has facilitated accurate information of slider excitations by varying the randomness of laser texture patterns. Spectrogram analysis was also applied to study various slider air bearing designs. This scheme of analysis has been demonstrated to be useful to study laser texture patterns and slider designs.