Estimating hemispherical scatter from incident plane measurements of isotropic samples scattering from both bulk and surface irregularities

In the mid-1970's it became apparent that incident plane scatter data could be represented by simple two or three parameter expressions. This realization made possible the generation of stray light estimation codes which are used on everything from military weapons, to telescopes, to car headlights to flat panel display systems. Almost all of these applications estimate hemispherical scatter from incident plane measurements. The authors' 2012 review of this process was limited to samples scattering just from surface roughness. In this paper hemispherical measurements are compared to calculations made from incident plane measurements using isotropic samples that scatter from bulk irregularities as well as surface scatter. The issue of non-isotropic samples is briefly introduced. The data is also analyzed to investigate reciprocity.