INVESTIGATION OF THE FEASIBILITY OF THE USE OF LASER OPTOACOUSTIC DETECTION FOR THE DETECTION OF EXPLOSIVES FINAL REPORT - EQUIPMENT SYSTEMS IMPROVEMENT PROGRAM

• NCJ Number: 35583
• Author(s): ANON
• Date Published: 1976
• Length: 107 pages
• Contract Number(s): J-LEAA-025-73; 44343-V
• Sponsoring Agency: Aerospace Corporation; US Dept of Justice; US Dept of Justice NIJ Pub
• Corporate Author: Case Western Reserve University
• Sale Source: National Institute of Justice/
• Publication Type: Report (Study/Research)
• Language: English
• Country: United States of America

Annotation

REPORT ON A STUDY TO EXPLORE THE FEASIBILITY OF DETECTING VARIOUS EXPLOSIVE VAPORS IN THE PRESENCE OF KNOWN INTERFERENCES, USING THE TECHNIQUE OF LASER OPTOACOUSTICS.

Abstract

IN USING THIS TECHNIQUE, A LASER BEAM IS FOCUSED INTO A CELL CONTAINING A GAS SAMPLE OF INTEREST. IF CERTAIN GAS SAMPLE CONSTITUENTS ABSORB THIS RADIATION, THE GAS WILL HEAT UP, THEREBY PRODUCING AN INCREASE IN PRESSURE WHICH CAN BE DETECTED BY A SENSITIVE MICROPHONE. UTILIZING BOTH CARBON DIOXIDE AND CARBON MONOXIDE LASERS, THIRTY-NINE WAVELENGTHS IN THE 6, 9, AND 11 MICROMETER SPECTRAL REGIONS OF THE INFRARED WERE SCANNED. NINE EXPLOSIVES WERE INVESTIGATED AT A VARIETY OF AVAILABLE WAVELENGTHS. IN THE 6 MICROMETER REGION, STRONG INTERFERENCE BY WATER VAPOR MADE THE SENSITIVE DETECTION OF EXPLOSIVES VAPORS INFEASIBLE. IN THE 9 AND 11 MICROMETER REGIONS, INTERFERENCES WERE SUBSTANTIALLY REDUCED, AND CERTAIN EXPLOSIVE VAPORS COULD BE SENSITIVELY DETECTED. ADDITIONAL MEASUREMENTS ARE RECOMMENDED TO VERIFY THAT THE TECHNIQUE HAS A PARCTICAL FEASIBILITY. (AUTHOR ABSTRACT)