On the existence of a Brewster angle for solid side incidence on periodically rough surfaces

Recently the authors have described the diffraction of horizontally polarized sound on periodically rough solid-liquid interfaces [Nico F. Declercq et al., IEEEUFFC 49(11), 1516-1521]. This has lead to the simulation of generated Love waves. This in combination with the theory of the diffraction of vertically polarized sound, where the generation of Scholte-Stoneley waves can be simulated, has resulted in the possibility to simulate what happens to elliptically polarized incident sound. It is shown that the rough surface can act as a polarization filter for normal incident sound. The model also describes the existence of a Brewster angle, where reflected sound becomes pure shear polarized. Hence a device is possible that basically consists of an isotropic solid being periodically corrugated and being able to filter out longitudinal waves when pure shear waves are necessary for example for NDT.