“…There are a number of spectroscopy techniques being developed for standoff detection of liquid and solid materials on surfaces. These techniques include laser-induced breakdown spectroscopy (LIBS) 1,2 , Raman spectroscopy 3,4,5 , infrared absorption/reflectance spectroscopy 6,7,8 , and photothermal spectroscopy 9 . LIBS systems have demonstrated favorable signal-to-noise from standoff distances up to 30 meters, but can only determine elemental composition (i.e.…”