Current lidar system used for bioaerosol detection utilize either elastic backscatter to detect the presence of any aerosol cloud, or use UV induced fluorescence to detect a potential bioaerosol. We are examining the possibility of using a broad bandwidth (hyperspectral) lidar system to estimate size distributions of aerosol clouds that may possess respirable biological particles. An optical parametric oscillator has been specially designed and fabricated for broad bandwidth operation in the 1.4 to 1.8 micrometer spectral region when pumped with a frequency doubled Nd:YAG laser. We have determined the spectral bandwidth, output, and pumping power characteristics of this device, and we have modeled the feasibility of using this as a source for an aerosol sizing lidar. A novel inverse Monte Carlo (IMC) technique was developed to analyze backscattering data that would result from a lidar system based on this device. Lidar simulation results show that good estimates of size distributions can be extracted for aerosols which have a 1 to 10 micrometer size range even when the signal to noise ratio is only 3:1.

Date Published: 13 March 2001
PDF: 8 pages
Proc. SPIE 4206, Photonic Detection and Intervention Technologies for Safe Food, (13 March 2001); doi: 10.1117/12.418718

Published in SPIE Proceedings Vol. 4206:
Photonic Detection and Intervention Technologies for Safe Food
Yud-Ren Chen; Shu-I Tu, Editor(s)