Abstract: A compact scanning apparatus has an infrared laser adapted to emit light. The light is delivered as a beam by an optical system to illuminate an interrogation area on the surface of an object being scanned. Such illumination has sufficient intensity and duration to cause selective desorption of molecules of the contraband substance, which are present on the surface, without substantially damaging the surface. A collection system collects at least a portion of the desorbed molecules. At least a portion of the collected molecules is thermally decomposed to form NO2 and transferred to a reaction cell containing an aqueous, alkaline, luminol-containing solution. The NO2 reacts with the luminol to produce light by chemiluminescence. A light detector registers the presence of this light as indicative of the detection of the contraband substance, and activates a signaling device to provide an audible or visible alarm.

Abstract: A compact scanning apparatus has an infrared laser adapted to emit light. The light is delivered as a beam by an optical system to illuminate an interrogation area on the surface of an object being scanned. Such illumination has sufficient intensity and duration to cause selective desorption of molecules of the contraband substance, which are present on the surface, without substantially damaging the surface. A collection system collects at least a portion of the desorbed molecules. At least a portion of the collected molecules is thermally decomposed to form NO2 and transferred to a reaction cell containing an aqueous, alkaline, luminol-containing solution. The NO2 reacts with the luminol to produce light by chemiluminescence. A light detector registers the presence of this light as indicative of the detection of the contraband substance, and activates a signaling device to provide an audible or visible alarm.