Rayleigh wave interference

Using a ray-tracing technique, one may understand this mechanism understood as follows. The period of this variation results from interference between the two components. Figure 6 shows one component which is spectrally reflected at normal incidence, while the second one undergoes a lateral shift on incidence and reradiates at the critical phase-matching angle for the surface acoustic wave (also referred to as leaky Rayleigh waves ). 

The diffraction of light waves in such a film can be treated in the same way used by Rayleigh, that is, applying (macroscopic) Maxwell equations with the appropriate boundary conditions at both surfaces. Afterward it was found that the same answers are obtained when the interference of the reflected, refracted, and diffracted waves are treated in an elementary fashion by adding the diffraction of the single surfaces with appropriate phase factors. 

Lichtenbelt et al. (19) made a detailed comparison of extinction cross sections for real doublets and for hypothetical doublets coalesced into spheres. Using the Rayleigh-Debye theory for a up to three, Lichtenbelt et al. determined that the coalescence assumption leads to 10% larger values of the scattering cross section than would be found for real doublets created in coagulation. This is because a real doublet is less compact than a coalesced doublet of the same volume therefore, the interference between light waves, scattered by different parts of the real... 

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