Development of a portable optical frequency comb for open-path measurement based on NALM mode-locked fiber laser

Abstract We developed a portable optical frequency comb for open-path measurements using a polarization-maintaining nonlinear amplifying loop mirror-type fiber comb as a light source. The output had a power of 140 mW and a broadband near-infrared spectrum from 1100 to 2300 nm, allowing operation at distances up to 90 m. Furthermore, open-path measurements were performed at a propagation distance of 40 m. The average power and spectrum after open-path propagation were sufficient for spectroscopic measurements. Finally, we measured optical heterodyne signals under open-path propagation, demonstrating that the developed portable comb can be applied to dual-comb systems.