Standoff Interaction Assessment Using High-Energy Laser-Induced Oxidation Spectroscopy

In light of the widespread use of high-energy lasers (HELs) for a variety of purposes, for example, standoff (> 100 m) applications, will require the ability to monitor in real time the interaction with processed materials. While multiple sensing methods have been successfully developed for industrial HEL systems operating at close range, they are not compatible with the unique requirements of long-distance applications. Here, high-energy laser-induced oxidation spectroscopy (HELIOS) is demonstrated on carbon steel coupons as an efficient standoff assessment method compatible with long distance HEL applications. Acute monitoring of spectral features from thermally excited iron atoms and oxides, corroborated with real-time temperature measurements, reveals the interaction mechanisms at play.