Antireflective properties of pyramidally textured surfaces at normal light incidence are studied by the finite-difference time-domain (FDTD) method. Optimal parameters for the period of the texture and the pyramid height are found. The asymptotic behavior of the reflection coefficient with an increasing height-to-base size ratio for the pyramids is also estimated for two limiting approximations: the effective medium theory (EMT) and geometric optics. For calculations in the geometric optics limit the ray tracing method was applied. The FDTD results for these limits are in agreement with the EMT and with the ray tracing calculations. It was found that the key factor influencing the optimal scatterer size is the character of the substrate tiling by the pyramid bases.
© 2010 Optical Society of America
Original Manuscript: September 17, 2009
Revised Manuscript: November 27, 2009
Manuscript Accepted: November 29, 2009
Published: January 11, 2010
Alexei Deinega, Ilya Valuev, Boris Potapkin, and Yurii Lozovik, "Antireflective properties of pyramidally textured surfaces," Opt. Lett. 35, 106-108 (2010)