Pyramid-Shape Light Coupler for Multi-Quantum-Well Photodetectors

Wavelength-independent light couplers in the form of planar arrays of pyramids have been proposed for use on multiple-quantum-well infrared photodetectors. Wavelength-independent light couplers are needed for focal-plane arrays of QWIPs designed to operate in multiple and/or broad wavelength bands. In the proposed pyramid light couplers, wavelength independence would be achieved by sizing and shaping the pyramids to exploit reflections and refractions that, to a first approximation, depend on geometry only.