On the Generalized Radiance Associated with Radiation from a Quasihomogeneous Planar Source

The properties of the (generalized) radiance associated with a quasihomogeneous planar source and with the optical field it generates are discussed. In the source plane the radiance is found to satisfy the usual postulates of conventional radiometry. An estimate is obtained for the distance along a straight line over which the radiance remains substantially unchanged. If the source is strictly homogeneous or if the field is treated in the paraxial approximation, the radiance is shown to obey the conventional propagation law exactly.