Simultaneous measurement of distance and speed via frequency-modulated continuous-wave LIDAR system based on H13C14N gas cell

Traditional frequency-modulated continuous-wave lidar is to measure the distance of the target through the spectrogram of the beat signal. In this paper, we propose a lidar system to obtain distance and speed at the same time. The distance and speed of the moving target are extracted by product of the delay time obtained by (HCN)-C-13-N-14 standard gas cell and the fitting frequency modulation rate obtained by Fabry Perot cavity, which can avoid spectral broadening. The experimental results show that the speed resolution of the system was 10 mu m/s, the mean error of the speed measurement from 0.1mm/s to 100mm/s was less than 162 mu m/s, and the mean standard deviation was less than 523 mu m/s. When the speed was less than 10mm/s and the distance was about 4.5m, the mean standard deviation of the distance was less than 163 mu m. With the advantages of light computation requirements, a simple optical path and measurement results with good repeatability and accuracy, this system has high practical value in precision industrial manufacturing.