Multi-wavelength, bi-directional fiber optic transceivers based on wavelength selective photodiodes

摘要

An optical transmission system provides wavelength demultiplexing at two or more frequencies with two or more photodiodes. The photodiodes are arranged so that the optical signal is initially incident upon a first photodiode that selectively receives at a first wavelength through the use of dichroic coatings and selectively absorbing layers within the photodiode. In addition the first photodiode reflects a portion of the incoming signal onto a second photodiode which then selectively receives at a second wavelength through the use of dichroic coatings and selectively absorbing layers within the photodiode. Additional signals of differing frequencies can be received by adding an additional photodiode for each channel to be separated.