Metallic triangular pillar grating arrays for high transmission polarizers for air:glass interfaces

A metallic one-dimensional moth eye structure that can be applied at the interface between glass and air to act as an optical polarizer with high transmission and high polarization extinction ratio (PER) is introduced. The metallic triangular grating array (MTGA) is designed by effective medium approach, with the expected performance confirmed by numerical simulations. A transmission of 99.12% and PER of 56.02 dB are predicted. Furthermore, the structure provides >99% transmission over a 450 nm spectral bandwidth for a 4 degree angled surface. In addition, the MTGA has been applied to a Fresnel zone plate (FZP), which enables both polarizing and focusing with 9.27% higher field intensity than the conventional FZP. The proposed metallic triangular array structure proposed here will provide highly-efficient polarization state selection. (C) 2019 The Japan Society of Applied Physics