A thickness-varying sub-wavelength grating focusing lens for TE polarization light

Abstract

A focusing lens for TE polarization light based on silicon sub-wavelength gratings using two different thicknesses is proposed. The properties are numerically studied with Finite Element Method (FEM). Total transmissivity is 72% and the full-width-half-maximum (FWHM) at focal plane is 0.8μm at a wavelength of 1550nm.