US Patent 9584246 Wavelength division multiplexing optical receiver

The present invention relates to a wavelength division multiplexing optical receiver and eliminates excess loss of one polarization component while eliminating the need for a polarization-independent operation of a light receiver. An input waveguide, made of a silicon wire waveguide, is connected to a loop waveguide equipped with a polarization rotator over a polarization beam splitter. A ring waveguide equipped with an output waveguide configuring an add-drop ring resonator array is optically connected to the loop waveguide. The output light from ports at both sides of the output waveguide is incident onto first and second light-receiving surfaces of a light receiver such that the optical distances are equal to each other.