Three-dimensional displacement measurement system based on FMCW self-mixing interferometry and FPGA technology

We introduce a system for three-dimensional (3D) displacement measurement based on frequency-modulated continuous-wave (FMCW) self-mixing interferometry (SMI) and field-programmable gate array (FPGA) technology. Through the integration of frequency division multiplexing and FPGA-based parallel processing, this system achieves real-time 3D displacement measurement with only a single laser source. The experimental results indicate that the system’s relative error in real-time 3D displacement measurement is less than 0.93%. This method provides a solution to the challenging problem of balancing accuracy, real-time performance, and portability in 3D precision displacement measurement systems and has broad application prospects in the fields of precision machining and manufacturing.