Experimental study on standoff detection of explosives traces using Laser Raman spectroscopy: challenges and possible solution

The detection and identification of explosive materials is required to defend the military forces and civilians. In this study we propose an integrated optoelectronics system composed of Raman Spectroscopy System and visible/near infrared hyperspectral camera for standoff real time in situ detection and identification of explosive traces on different background materials. Both systems are combined to overcome the limitations when using each system separately. For the preliminary investigation of the system efficiency, the detection of the most common explosive material, the trinitrotoluene (TNT), is tested. The proposed HSI system is tested for explosive detection at distance range from 1 to 30 m. The HSI successfully achieved detection of the traces of TNT at 30 m distance and detection limit of 1 µg/cm2. On the other hand, the Raman system could successfully detect a sample of 20 µg/cm2 of TNT at 1 m. Limitations of both systems are discussed. The obtained results show the ability of the recommended integrated system to overcome the limitations of each system separately and hence to accurately detect and identify the explosive materials.