DIFFUSIVE MEDIA CHARACTERIZATION WITH LASER SPECKLE

The statistical properties of laser speckle with partially coherent li ght are related to the scattering characteristics of an optically diff use material. A diffusion equation model is shown to yield a speckle c ontrast ratio that agrees well with measurements of opaque plastics of varying thicknesses. We show that partially coherent light can be use d to determine material parameters for highly scattering media. Measur ed data for stratified materials with differing scattering properties indicate that this technique may be useful in detecting inhomogeneitie s. (C) 1997 Optical Society of America.