Laser-Induced Breakdown Spectroscopy: A Review of Applied Explosive Detection.

摘要

The complex chemical nature of the current military environment complicates the ability of the Warfighter to detect an explosive threat prior to detonation. The challenge is further complicated when standoff or proximal detection is needed. In this report, results from a survey of current literature and available industry data are used to provide an assessment of laser-induced breakdown spectroscopy (LIBS) phenomenology for explosives detection, as well as recognize potential gaps in knowledge. Examination of the literature reveals that there are many strengths and challenges associated with the LIBS techniques and its variants. These challenges, such as varied signal intensities due to matrix effects, are being addressed by examining the role of pulse duration, wavelength, and fluence in LIBS and by developing parallel techniques (e.g., dual-pulse LIBS) to reduce or nearly eliminate interferents. Despite advances in the LIBS research to mitigate these matrix effects, sample analysis remains arduous due to the complex emission spectra obtained. Therefore, the use of chemometrics to aid in the discrimination of hazardous material has recently been examined with some limited success. Based on the information gathered from this report, a list of recommendations for future research and/or development to increase the utility of the technique for trace standoff explosive detection is provided.