Application Of Variational Mode Decomposition Method In Fourier Transform Profilometry

For the spectrum overlapping problem caused by the fundamental frequency component and the zero-frequency component in the Fourier Transform Profilometry (FTP), a new method based on Two-Dimensional Variational Mode Decomposition (2DVMD) is proposed to extract the fundamental frequency components, and it can adaptively decompose the fringe pattern into background part and fringe part. Comparing 2DVMD method and Bidmensional Empirical Mode Decomposition (BEMD) method in zero-frequency components removing, it is found that 2DVMD method can perfectly separate the fundamental frequency component from the zero-frequency component and can extract the fundamental frequency information completely, thus avoiding the loss of the fundamental frequency information caused by filtering. Then the inverse Fourier transform and the phase unwrapping algorithm are performed to the extracted fundamental frequency component, it can effectively recover the abrupt change information of the measured object. Numerical simulations and experimental results show that the FTP based on 2DVMD method can reconstruct the details of the measured object more effectively than the FTP based on filtering method.