Patent ID: 6797944
Filing Date: 2004-09-28
Classification: G01N,G01V

Abstract:
A method of detecting the presence of a preselected contraband substance on a surface of an object comprising the steps of:a. illuminating an interrogation area of said surface with a pulsed beam of light emitted from an infrared laser, said illumination having sufficient intensity and duration to cause selective ablation of molecules of said contraband substance present on said surface without substantially damaging said surface; b. collecting at least a portion of said desorbed molecules in a collection system; c. analyzing said portion in a chemical analysis system, the system being associated with said collection system and comprising a detector responsive to the presence in said chemical analysis system of said contraband substance; d. outputting an electrical signal representative of said presence of said contraband substance; and e. activating signal means operably connected to said chemical analysis system in response to the output of said electrical signal.