- Franco Gori: Istituto Nazionale per la Fisica della Materia and Dipartimento di Fisica, Università Roma Tre, Via della Vasca Navale 84, 1-00146 Rome, Italy.
It is shown that any partially polarized, partially coherent source can be expressed in terms of a suitable superposition of transverse coherent modes with orthogonal polarization states. Such modes are determined through the solution of a system of two coupled integral equations. An example, for which the modal decomposition is obtained in closed form in terms of fully linearly polarized Hermite Gaussian modes, is given.