Scattering by random particles on optical surfaces

An analytical technique has been developed for calculating the angle-resolved light scattering by contaminant particles on smooth opaque surfaces. The analytical method was tested by a comparison of measured and calculated bidirectional reflectance distribution function (BRDF) values for contaminated surfaces. BRDF values were calculated from particle sizes, shapes, and areal densities obtained from scanning electron microscope images of the contaminated sui-faces by a Princeton gamma-tech image analyzer. Measured and calculated BRDF values agreed to within the uncertainty associated with the particle characterization process for most scattering angles. (C) 1996 Optical Society of America