II Enhanced Backscattering in Optics

Publisher Summary This chapter describes enhanced backscattering in optics. The chapter considers backscatter enhancement in light scattered from a body embedded in a random medium. A similar phenomenon occurs in multiple scattering of light in a randomly inhomogeneous medium where there are no clear-cut scatterers that stand out against a background. The effects of backscatter enhancement and weak localization are phenomena, in which coherent paths of the Watson-Ruffine type are essential. The chapter describes multiple new manifestations of coherent effects in backscattering. These include the effects of long-distance correlations, the partial reversal of the phase front in a random medium, the magic cap effect, antispecular scattering by very rough random surfaces, and backscattering involving surface waves. The chapter also discusses the opposite case of a small number of scatterers, in which summation cannot be replaced with integration.