Spherical object in radiation field from a point source

A general formula for calculating radiative fluxes from point sources of radiation incident on spherical objects was derived using some fundamental laws of classical radiometry. This formula was derived in the Cartesian coordinate system, 0xyz, where the coordinates, x, y, and z, determine the position of the spherical object with respect to the point source. The obtained solution was dependent on the radius of the object, and on the function describing the intensity of the radiation. A specific solution for calculating fluxes of isotropic radiations was presented and selected calculations were illustrated graphically. (C) 2004 Optical Society of America.