| Abstract: | A cluster of point sources can generate optical radiation in a manner substantially different from what characterizes the emission of a single point source. Such differences are mainly caused by the cooperation of the sources and are even more remarkable under particular electromagnetic boundary conditions. Furthermore, the geometry of the problem cannot be ignored as it makes an important contribution to the contrast between single source and collective behaviour. This paper tries to explore the subject in view of its applications to coherent scattering that is typical of non‐linear Raman processes. To this end, the classical theories of electromagnetic radiation from a point source (treated as a randomly oriented Hertzian dipole) and of partial coherence are joined into a unified formalism to evaluate light emission from a volume seen as a collection of point sources embedded in a layered medium. In certain reasonable circumstances and beyond the undeniable complexity of the problem, the formalism leads to the relevant advantage of analytical results for the power radiated outside the medium. In other more general cases, fast Fourier transforms can be used in principle. The possibility and convenience of using the theory to model micro‐CARS imaging are illustrated and discussed. Copyright © 2010 John Wiley & Sons, Ltd. |
