Fuchs, F.F.FuchsHugger, StefanStefanHuggerJarvis, J.J.JarvisYang, QuankuiQuankuiYangOstendorf, RalfRalfOstendorfSchilling, ChristianChristianSchillingBronner, WolfgangWolfgangBronnerDriad, RachidRachidDriadAidam, RolfRolfAidamWagner, J.J.Wagner2022-03-132022-03-132016https://publica.fraunhofer.de/handle/publica/39385710.1117/12.2223581We perform active hyperspectral imaging using tunable mid-infrared (MIR) quantum cascade lasers for contactless identification of solid and liquid contaminations on surfaces. By collecting the backscattered laser radiation with a camera, a hyperspectral data cube, containing the spatially resolved spectral information of the scene is obtained. Data is analyzed using appropriate algorithms to find the target substances even on substrates with a priori unknown spectra. Eye-save standoff detection of residues of explosives and precursors over extended distances is demonstrated and the main purpose of our system. Using a MIR EC-QCL with a tuning range from 7.5 µm to 10 µm, detection of a large variety of explosives, e.g. TNT, PETN and RDX and precursor materials such as Ammonium Nitrate could be demonstrated. In a real world scenario stand-off detection over distances of up to 20 m could be successfully performed. This includes measurements in a post blast scenario demonstrating the potential of the technique for forensic investigations.enexternal cavity quantum cascade lasersactive hyperspectral imagingmid-infrared spectroscopystand-off detection of explosives667conference paper