Modeling light scattering by spherical pores for calculating the transmittance of transparent ceramics – All you need to know.

• Transmittance predictions based on pore scattering in transparent ceramics. • Mie theory and approximations (Rayleigh, Fraunhofer, van de Hulst, Rayleigh-Gans). • Different transparent ceramics (magnesium aluminum spinel, magnesia, YAG, yttria). • The Rayleigh-Gans approximation provides best predictions for small pore sizes. • Van de Hulst's approximation is useful for all pore sizes, including large pores. In this paper transmittance predictions based on residual pore scattering in transparent ceramics with cubic crystallites via Mie theory and its approximations (Rayleigh, Fraunhofer, van de Hulst and Rayleigh-Gans, including the small- and large-size limits) are recalled and systematically compared. Due to the high phase contrast, the difference between different types of ceramics is of secondary importance, so that the essential conclusions are of general validity for all types of transparent ceramics. It is shown that the Rayleigh-Gans approximation and its large-size limit provide surprisingly good transmittance predictions, although it has not often been used in the ceramic literature. The main conclusion of this paper is that, of all the approximations presented here and used in ceramic science so far, the van de Hulst approximation is the one that most closely approaches the exact Mie results, although it has been largely ignored in the literature on transparent ceramics so far. [ABSTRACT FROM AUTHOR]