Wave Beam Propagation in Layered Media

—Using rather general assumptions, wave beam propagation is considered in a medium,constituted of two half-spaces with smoothly changing properties, these latter changing stepwise at the half-spaces’ interface. Expressions for the beam-shape change in the course of propagation are obtained. General results are applied to a Gaussian beam propagating in a series chain, and to fields described by the Helmholtz equation.