ZHAO Yan,ZHANG Ai-ling,ZHANG Hai-wei.Simultaneous displacement measurement method of multiple targets based on laser self-mixing interference[J].Optoelectronics Letters,2021,17(3):165-169 Simultaneous displacement measurement method of multiple targets based on laser self-mixing interference Author Name Affiliation ZHAO Yan  School of Electrical and Electronic Engineering, Tianjin University of Technology, Tianjin 300384, China Tianjin Key Laboratory for Control Theory and Applications in Complicated Systems, Tianjin 300384, China  ZHANG Ai-ling  School of Electrical and Electronic Engineering, Tianjin University of Technology, Tianjin 300384, China  ZHANG Hai-wei  School of Electrical and Electronic Engineering, Tianjin University of Technology, Tianjin 300384, China  Abstract:       In order to simultaneously measure the displacements of multiple targets, the laser self-mixing interference (SMI) measurement method based on variational mode decomposition (VMD) is proposed. The SMI signal containing the motion information of the external targets is detected by a photodiode. The VMD can non-recursively decompose the mixed SMI signal into SMI signals corresponding to different external targets. The displacement signals can be reconstructed by fringe counting method and interpolation method. The experimental results show that the displacement signals of different external targets can be reconstructed with half wavelength accuracy, which verifies the correctness and feasibility of this method. This method can improve the measurement efficiency, which offers an effective method for the multi-channel displacement measurement. Hits: 805 Download times: 2 View Full Text    Download reader