Optical arrayed waveguide grating devices

摘要

It is found that the use of a multimode interference (MMI) section to flatten the pass-bands of an arrayed waveguide grating (AWG) multiplexer/demultiplexer or comb filter device introduces undesirable wavelength dispersion into those pass-bands if that MMI section mixes modes of more than two different orders, and if the grating of that device is a "uniform' grating whose waveguides are equally (minimally) attenuating, and in which the optical path length difference between each adjacent pair of waveguides 40 of the array is the same. This dispersion can be substantially compensated by appropriate "tailoring' of the grating to remove such uniformity