On the information content of the light backscattering and transmittance curves in aerosols

Propagation of laser light in droplet aerosol media was studied numerically and experimentally. In optically tenous aerosols the backscattering signal intensity is much weaker than the transmittance, but exhibits a specific substructure and is very sensitive to optical properties of aerosols and their size. Measurements show an excellent agreement of the experimental and theoretical curves for single scattering conditions. In optically dense aerrosol media with optical depths of the order of unity and above, the backscattered light-flux intensity becomes comparable with the transmitted light-flux intensity. Experimental data indicate that this intensity enhancement is dominated by multiple sccattering and can provide important information regarding the backscatter-to-extinction signal ratio in various aerosol media.