The early editions of Optical Scattering were dominated by the exploration of the relationship between roughness and scatter from optically smooth surfaces by developing the relationship between the surface statistics and the measured surface scatter in BRDF units. The upper limit roughness for using scatter measurement to calculate surface roughness was well established. The basic concept of reciprocity, as it applies to scatter, could have been in the earlier editions and that mistake is corrected in this edition. The third edition added the use of scatter in the semiconductor...