Ciena Corporation
Managing stray light in integrated photonics devices

Abstract:

A first photodiode is integrated within at least a first layer of one or more semiconductor layers, the first photodiode comprising an active area optically coupled to a guided mode of a first waveguide to couple the first photodiode to an optical distribution network. One or more associated photodiodes are associated with the first photodiode integrated within at least the first layer in proximity to the first photodiode. An active area of a single associated photodiode or a sum of active areas of multiple associated photodiodes is substantially equal to the active area of the first photodiode. None of the associated photodiodes is coupled to the optical distribution network. Electrical circuitry is configured to generate a signal that represents a difference between (1) a signal derived from the first photodiode and (2) a signal derived from a single associated photodiode or a sum of signals derived from multiple associated photodiodes.