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Compact detector unit based on the butterfly assembly for trace gas analysis

The detection and identification of molecular gases are of high relevance in many applications within healthcare, production monitoring and safety as well as environmental monitoring. One of the major difficulties of trace gas analysis is due to the bulky and expensive systems, what excludes both mobile and handheld use. For this purpose we present our new system based on the Quartz Enhanced PhotoAcoustic Spectroscopy (QEPAS), which can provide the required properties for gas analysis. We have developed a compact detection unit where DFB laser, collimation optics and QTF are integrated in a 14-pin butterfly housing. Therefore an optimization of the DFB laser chips will be presented too. The results show, that the laser diodes not only provide excellent performance, but also allow a detection limit for the greenhouse gas methane and carbon dioxide in the ppm range.