Remote mid-infrared sensing using chirped laser dispersion spectroscopy

摘要

A new spectroscopic technique for remote molecular detection is presented. Chirped Laser Dispersion Spectroscopy (CLaDS) uses a two-color dynamic interferometric heterodyne detection to measure optical dispersion caused by molecular transitions. The dispersion sensing is based on measurement of instantaneous frequency of an optical heterodyne beatnote which provides high immunity to optical power fluctuations. Thus CLaDS is well suited to long distance remote sensing and open-path monitoring. In this work we present CLaDS experimental setup for remote sensing of nitric oxide using 5.2 μm quantum cascade laser. System performance as well as advantages and limitations are discussed.