Patent ID: 10809426

Abstract:
Disclosed is a new class of wideband reflectors that are relatively insensitive to deviations from the design parameters. The reflectors are materially sparse while providing high reflectance across wide spectral bands. In some embodiments, a device comprises a substrate and a grating layer disposed on the substrate, wherein the grating layer comprises a periodic grating structure and a sublayer beneath the grating structure and adjacent to the substrate, the grating layer and the sublayer having the same index of refraction. These compact, low-loss elements complement conventional thin-film reflectors while possessing properties not available in thin-film multilayer stacks. The reflectors are based on a fundamental resonance effect, the guided-mode resonance effect, that occurs in periodic structures. Disclosed herein are both one-dimensional and two-dimensional reflectors m zero-contrast embodiments. The disclosed reflectors can be used in various electromagnetic spectral regions for various useful applications.