Laboratory target reflectance measurements for coherent laser radar applications

Signature characteristics of several materials under CO2 laser illumination are measured using a laboratory reflectometer. The reflectometer is a monostatic direct-detection system. Measured quantities include sample correlation, statistical signal distribution and its mean and standard deviations, and reflectivity of diffuse materials. Measured density distribution and number of speckle cells are compared with theoretical predictions. The measurements show that the flame-sprayed aluminum is well suited as a high-reflectivity diffuse standard, while sandpapers in general exhibit specular characteristics at near-normal incidence to the sample surface.