  We present a detailed study of the gaussian laser propagation through a
dielectric system composed by two right angle prisms. We investigate the
transition between the spatial coherence limit, which exhibits wave-like
properties and for which the resonance phenomenon can be seen, and the
decoherence limit, which exhibits particle-like properties and for which the
multiple diffusion occurs. We also analyze the tunneling at critical angles. In
our numerical analysis, we shall use BK7 and Fused Silica prisms and a gaussian
He-Ne laser with a wavelength of 632.8 nm and beam waists of 2 mm and 200
micron.
