Low-reflective Wire-grid Polarizers with an Absorptive Layer Formed by Glancing Angle Deposition

Abstract

We have developed wire-grid polarizers with low reflectivity in the visible region. The polarizers consist of a bilayered structure of an absorptive layer and a (transparent) gap layer on sub-wavelength pitch gratings made of aluminum. The bilayered structure functions as a highly effective antireflection coating for wire-grid with high reflectance. In order to realize these multilayered wire-grid, the glancing angle deposition technique was used to deposit the absorptive layer just above the Al wire-grid covered with the SiO₂ gap layer. Both low reflectance and high transmittance in the desired wavelength range were achieved by optimizing the thickness of each layer.