Minimally invasive dual-fiber coupled laser hygrometer for fast in-situ gas analysis with absorption path length in the millimeter range

摘要

Direct tunable diode laser absorption spectroscopy (dTDLAS) offers the possibility for highly selective, fast, calibration-free and sensitive in-situ measurements of individual gas components. Minimally invasive fiber-coupled sensors are especially interesting for numerous applications e.g. process or combustion analysis, where compact optical sensors for applications with limited optical access are required. Especially the sensor development for the gas analysis in internal combustion engines is challenging as harsh environmental conditions, very high time resolution and very confined space have to be considered.