Abstract

The diffusion equations whose derivatives in time have prompted controversy in recent papers are reexamined from a different point of view. The resulting equation is demonstrated to agree with the first-order differential equation with respect to the time that was given by Furutsu’s theory. It is also shown that the reduced light velocity of the diffuse pulse, predicted by Ishimaru’s theory, is a result carried beyond the range of the applicability of the diffusion approximation utilized and is not characteristic of the diffusion.

© 1984 Optical Society of America

Difference between Ishimaru’s and Furutsu’s theories on pulse propagation in discrete random media

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