Patent ID: 9052447
Filing Date: 2015-06-09
Classification: G02B

Abstract:
1. A de-multiplexer, comprising: an input port configured to couple to an optical waveguide to receive an optical signal; a sub-wavelength grating, optically coupled to the input port, configured to magnify the optical signal, wherein, along a direction perpendicular to a propagation direction of the optical signal, an effective index of refraction of the sub-wavelength grating is larger at a center of the sub-wavelength grating than at an edge of the sub-wavelength grating, and wherein a sign of the magnification depends on a direction of propagation of the optical signal; an optical device, optically coupled to the sub-wavelength grating, configured to image and diffract the optical signal using a reflective geometry so that different diffraction orders of the optical device propagate through the sub-wavelength grating, wherein the optical device includes a diffraction grating on a curved surface; and output ports, optically coupled to the sub-wavelength grating, configured to couple the different diffraction orders of the optical device to additional optical waveguides.