Spectroscopic material determination via LIBS and CRDS

Abstract

Laser Induced Spectroscopy (LIBS) and Cavity Ring Down Spectroscopy (CRDS) are promising chemical sensor technologies for small mobile robotic platforms. LIBS leverages the natural surface adsorption from the atmosphere to interior and exterior surfaces for signal enhancement. In this work, a material or class-specific adsorption surface is combined with a miniature version of a CRDS ring cavity to achieve a similar signal enhancement for CRDS. The combination of LIBS and CRDS allow the analysis of both classes of materials - those with long adsorption times to permanent surfaces such as walls and those that require real time sampling of ambient concentrations. This paper emphasizes issues related to package miniaturization, power budget limitations and ruggedness as well as basic performance modeling of the instruments. Comprehensive sensing issues for material specific micro-detectors will be addressed. Computer simulations and some data are presented. Applications considered include the determination of need for remediation and the determination of the effectiveness of remediation techniques as well as the detection of hazards and intelligence gathering.