Perspectives of laser-photoacoustic spectroscopy in trace gas sensing

Abstract
Laser-based sensing techniques are attracting great interest in various fields of application, notably in trace gas monitoring and analysis. Among various detection schemes, photoacoustic monitoring offers some unique features. The performance of a laser-photoacoustic system crucially depends on the availability of appropriate laser sources, modulation schemes and the design of the photoacoustic gas cell. Here we discuss various point-monitoring laser-photoacoustic sensor systems employing different lasers and acoustic cell configurations. Examples include laboratory gas analyses as well as in situ measurements.