Metrology tool and components therefor

Abstract

An optical coupler for a photonic integrated circuit comprising a first channel waveguide configured to guide electromagnetic radiation comprising a first wavelength. The optical coupler comprises a second channel waveguide configured to guide electromagnetic radiation comprising a second wavelength that is different to the first wavelength. The optical coupler comprises a slab waveguide optically coupled to the first and second channel waveguides and configured to guide electromagnetic radiation comprising both the first and second wavelengths. The optical coupler comprises a computer generated waveguide hologram optically coupled to the slab waveguide. The optical coupler comprises a metasurface optically coupled to the computer generated waveguide hologram.

Images