Monomer diffusion rates in photopolymer material. Part I. Low spatial frequency holographic gratings: Comment

We examine the statements in [J. Opt. Soc. Am. B 28, 658 (2011)] that a "confusingly wide range of values (of monomer diffusion rates) have been reported in the literature" and that the authors "provide unambiguous evidence that the monomer diffusion rate in a commonly used acrylamide polyvinyl alcohol-based material is of the order of 10^-10 cm ²/s". We discuss this result and briefly summarize the differences between two models which have been proposed to explain behavior of holographic photopolymers and consider their implications.