Frequency modulation spectroscopy for chemical sensing of the environment

摘要

Abstract: Frequency modulations spectroscopy (FMS) with infrared lasers is an attractive technique for a number of environmental chemical sensing problems. The technique combines high detection sensitivity with high detection speed and, when implemented with tunable infrared laser sources, is capable of detecting numerous chemical species in the atmosphere. To date, the technique has been demonstrated with semiconductor diode lasers and carbon dioxide lasers, and absorptions at the 10$+$MIN@7$/ level have been detected. We will review the principles and status of FMS for chemical sensing and discuss applications in atmospheric and environmental monitoring.!