Photoacoustics: an acoustic method for trace gas measurements
نویسندگان
چکیده
The photoacoustic (PA) effect, the generation of sound by the absorption of pulsed or modulated light, has been known since the famous experiments of Alexander Graham Bell in 1880. Scientific and practical applications of the photoacoustic technique have been considerably promoted by the invention of laser, which is an ideal light source for photoacoustics. Recently, photoacoustic detectors play an increasing role in trace gas detection and analysis. The sensitivity of a small, simple and cheap photoacoustic detector is only slightly lower than that of a very sophisticated and expensive optical system equipped with a multipass optical absorption cell and a liquid nitrogen cooled infrared detector.
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تاریخ انتشار 2009