A ranging system based on dual-comb femtosecond laser ranging technology

In response to the urgent need for high-precision long baseline measurement in tasks such as precision assembly measurement of large space institutions and precise formation flight, a dual-comb femtosecond laser ranging engineering prototype was built to verify the engineering environmental adaptability of this technology. The absolute distance measurement technology based on nonlinear optical down-sampling principle is adopted, which widens the echo signal width from femtosecond level to nanosecond level, effectively avoided the problem of insufficient response rate of photo-detectors, overcomes the disadvantage of low precision of traditional pulse ranging, and achieves high-precision absolute distance measurement of long baseline targets. The optical and mechanical structure of femtosecond laser ranging prototype is designed for environmental adaptability. We conducted distance measurement experiments on the relative positions of multiple positioning points on a clean interval vibration platform and a 52m long baseline target distance measurement experiment on a conventional laboratory testing platform for the product. The results show that under both operating conditions, the product's ranging accuracy reaches the level of 10um, the system operates stably and can quickly and continuously measure dynamic micro displacement. At this precision level, the impact of laboratory air disturbance and environmental vibration on this product can be ignored, which provides important reference value for the subsequent engineering application of the product.