Ray tracing vs. electromagnetic methods in the analysis of antireflective textured surfaces: a first approach

摘要

We investigate the validity of the ray optics approach for the analysis of antireflecting structures used in photovoltaic solar cells. The antireflecting structure is simulated by a periodic grating with triangular profile and the reflected fields are calculated using two methods: one based on the ray optics approach and the other based on rigorous electromagnetic theory. As a first approach to the real problem, we consider a perfect conductive media. The parameter used for the characterisation of the problem is the wavelength to period ratio lambda/d. The theoretical analysis presented here shows important discrepancies between the results obtained using the ray tracing approximation and those obtained using a rigorous electromagnetic method, even for small values of lambda/d (of the order of 0.1) for which the geometrical optics approach is usually expected to hold. [References: 9]