Han Senmiao, Yang Linghui, Song Youjian, Niu Qiong, Shi Yanqing, Yu Hongyi, Hu Xinyuan, Zhu Jigui
State Key Laboratory Precision Measurement Technology and Instruments, School of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China.
Key Laboratory of Opto-Electronic Information Science and Technology of Ministry of Education, School of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China.
Rev Sci Instrum. 2024 Apr 1;95(4). doi: 10.1063/5.0198468.
Absolute distance measurements based on femtosecond lasers have been extensively studied for precision metrology and advanced manufacturing, with the advantages of traceability, high speed, and nanometer precision. However, in previous studies, the dual femtosecond laser ranging system showed limitations such as system complexity, lower integration, dead zone problems in single optical path detection, and high requirements for laser coherence. It is challenging to achieve a high degree of integration and large-scale continuous measurements using femtosecond lasers, ineluctably limiting practical applications in engineering fields. Here, based on the free-running dual femtosecond lasers and the nonlinear asynchronous optical sampling method, we design a highly integrated absolute distance meter. In particular, the dead zone problem is solved by the polarization multiplexing technique, and the digital control system and signal processing system are completed by the Field Programmable Gate Array (FPGA). The absolute distance meter enables rapid, continuous, and accurate measurements over a considerable range without dead zones, which paves a promising way for the integration, instrumentation, and industrial applications of femtosecond laser ranging systems.
基于飞秒激光的绝对距离测量已在精密计量和先进制造领域得到广泛研究，具有可追溯性、高速和纳米精度等优点。然而，在以往的研究中，双飞秒激光测距系统存在一些局限性，如系统复杂、集成度较低、单光路检测中的死区问题以及对激光相干性要求较高。利用飞秒激光实现高度集成和大规模连续测量具有挑战性，这不可避免地限制了其在工程领域的实际应用。在此，基于自由运行的双飞秒激光和非线性异步光学采样方法，我们设计了一种高度集成的绝对距离测量仪。特别地，通过偏振复用技术解决了死区问题，并由现场可编程门阵列（FPGA）完成数字控制系统和信号处理系统。该绝对距离测量仪能够在相当大的范围内进行快速、连续且准确的无死区测量，为飞秒激光测距系统的集成、仪器化及工业应用铺平了一条充满希望的道路。
