We present the application of a compact setup for real-time in situ trace-gas detection based on photothermal beam deflection (mirage-effect) spectroscopy to environmental monitoring and chemical analysis. The setup provides many advantages for local (nonremote) detection applications, such as rapid response and high sensitivity under true in situ conditions. The detection limit of C2H4 in open air is estimated to be 0.25 parts in 109, based on concentration calibration with the dominant noise that is due to atmospheric turbulence on a time scale of 1 s. Detection limits are extrapolated for other species, and applications are explored by real-time measurements of gas emissions from a variety of solid and semisolid samples.
© 1997 Optical Society of America
Bob L. Zimering and A. Claude Boccara, "Applications of a compact photothermal-deflection-based setup for trace-gas detection in real-time in situ environmental monitoring and chemical analysis," Appl. Opt. 36, 3188-3194 (1997)