Retrieve the Material Related Parameters from a Self-Mixing Signal Using Wavelet Transform

This paper presents a method for retrieving material related parameters using a self-mixing interferometric (SMI) configuration. The material sample to be tested is used form the external cavity of a laser diode (LD). A SMI signal generated from the SMI system carries the information of the cavity movement. By applying wavelet transform onto the SMI signals, both fundamental resonant frequency and the magnitude decay of the vibration from the external cavity can be obtained, from which, we can calculate a few material related parameters such as Young's modulus and internal friction.