Chinese Optics Letters, Vol. 17, Issue 9, 091202 (2019)
Large-scale absolute distance measurement with dual free-running all-polarization-maintaining femtosecond fiber lasers
Yuepeng Li1, Yawen Cai2,*, Runmin Li1, Haosen Shi1, Haochen Tian1, Mingzhao He3, Youjian Song1, and Minglie Hu1
- 1Ultrafast Laser Laboratory, 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
- 2Institute of Spacecraft System Engineering, China Academy of Space Technology, Beijing 100094, China
- 3National Institute of Metrology, Beijing 100029, China
We demonstrate a robust femtosecond LIDAR setup by using two free-running environmentally stable all-polarization-maintaining nonlinear amplified loop mirror mode-locked fiber lasers. Based on the asynchronous optical sampling method, a ranging accuracy of ±2?μm within 65?m has been achieved, as tested in an 80-m-long underground optical tunnel. Through the Kalman filter in real-time data processing, the measurement accuracy can be maintained at a 200?Hz update rate. This setup provides a practical tool for various large-scale industrial and astronomical ranging applications.