Laser self-mixing interferometry for micro-vibration measurement based on inverse Hilbert transform.

A novel micro-vibration reconstruction method based on inverse Hilbert transform is presented. By inversing either side of the SMI signal after Hilbert transform, micro-vibration can be reconstructed quickly and conveniently. In the paper, the principle of inverse Hilbert transform algorithm is studied. And, the effectiveness of the method is verified through simulated signals, and several experiments are carried out, including the self-mixing signal affected by speckle effect. The experimental results show that the external cavity phase can be rapidly extracted by inverse Hilbert transform algorithm, and the relative error is no more than 7%. [ABSTRACT FROM AUTHOR]