The assertion made by S. Kaushik in a recent paper [J. Opt. Soc. Am. A <b>14</b>, 596 (1997)] that the S-matrix propagation algorithm that he derived is new and represents an improvement over the earlier research is apparently incorrect. A review of the literature shows that every feature of the algorithm as presented in the above reference has been known for many years.
© 1998 Optical Society of America
Lifeng Li, "Vector Fresnel equations and Airy formula for one-dimensional multilayer and surface-relief gratings: comment," J. Opt. Soc. Am. A 15, 1006-1008 (1998)