PNNL

Abstract

In order to detect either aerosol or gaseous effluents at standoff distances, modern spectroscopic methods can use infrared light reflected from remote surfaces to detect the intervening species. The probing light can be either broadband or (nearly) monochromatic such as from a laser. How much light is returned to the sensor, either in a specular or diffuse fashion, depends not only on the output power of the source but also on the spectral properties of the reflective surface. In this paper, we report details on measurement of Surfaces of Opportunity (SOOs) used as part of the PICARD (Pursuing Intelligent Complex Aerosols for Rapid Detection) aerosol research program. The materials included surfaces of both high- and low-reflectivity, including e.g. aluminum plates, car body panels, marble, painted brick, etc. Both the total (diffuse + specular) and diffuse-only reflectance spectra from 7500 – 600 cm-1 (1.33 – 16.67 µm) were measured in the laboratory to investigate the possibility of their use as SOOs for standoff detection.