Abstract Submission - Etienne Rochat - Omnisens
Resonnant photoacoustic spectroscopy: a versatile and selective method for the measurement of NO, NO2 and NH3
Resonant photoacoustic spectroscopy is a laser based measurement method where light absorption is converted in an acoustic wave, which magnitude is directly and linearly proportional to the gas concentration. The sensing device can accommodate different lasers ranging from telecommunication wavelength to IR wavelength with virtually no modification so that swapping lasers allows for the measurement of different gases.
Extensive field comparison studies on ambient ammonia measurement made over the years by research institutes in Switzerland, Germany and in Netherland have shown that laser based technologies, and in particular photoacoustic spectroscopy, thanks to its selectivity and short reaction time is much more reliable and accurate than currently used reference methods. Amongst optical methods, photoacoustic spectroscopy distinguished itself by the fact that the detection limit scales linearly with the laser power, thus becoming even lower as more powerful lasers are commercially available.
We report on the design of a Quantum Cascade Laser based gas analyser, allowing for selective measurement of NH3, NO and NO2.
