Light detection system including a chiral optical element and optical elements with sub-wavelength gratings having posts with varying cross-sectional dimensions

摘要

Light-detection systems that do not destroy the light to be detected or change the propagation direction of the light are described. In one aspect, a light-detection system includes an optical element composed of a substrate with a planar surface and a polarization insensitive, high contrast, sub-wavelength grating composed of posts that extend from the planar surface. The posts and/or lattice arrangement of the posts are non-periodically varied to impart orbital angular momentum and at least one helical wavefront on the light transmitted through the optical element.