[OPTICAL REVIEW Vol. 7, No. 2 (2000) 112-114]

## Free-Space Propagation of the Generalized Radiance Defined in Terms of the Coherent-Mode Representation of Cross-Spectral Density Function

Andrey S. OSTROVSKY and Mario V. RODRIGUEZ-SOLIS

Facultad de Ciencias Fisico-Matematicas, Universidad Autonoma de Puebla, 72570 Puebla, Pue., Mexico

(Received September 30, 1999; Accepted January 7, 2000)

The equation for free-space propagation of the generalized radiance defined formerly by the authors in terms of the coherent-mode representation of the cross-spectral density function is derived within the accuracy of the paraxial approximation. It is shown that, in the short-wavelength limit, this generalized radiance obeys in a good approximation the fundamental radiative transfer law of classical radiometry.

Key words : generalized radiance, cross-spectral density function, coherent-mode representation, free-space propagation equation, radiative transfer law mass fractal, surface fractal, combined fractal, self-similarity, power law, fractal dimension