Ray path in a stratified absorbing medium

The ray tracing technique in absorbing, isotropic or anisotropic stratified media, and particularly in plane-stratified media is discussed. There are two approaches. One is to construct the complex refractive index vector and use the principle of stationary phase. The other is to impose a spatial beam signal on the medium having, e.g., a Gaussian profile and to find the peak of a component of the field intensity at each stratified layer. In this paper, we deal with the second approach. The resulting analytical expression for ray tracing is found to be identical with that obtained via the first method.