Abstract: A MUX, DEMUX or integrated combination MUX/DEMUX utilizing a discrete dispersion device (herein referred to as “D3” device), which includes at least one input port, at least one output port and an optical planar waveguide comprising a synergetic photonic bandgap quasi-crystal (“PBQC”) for guiding and supporting optical signals in a work bandwidth. The D3 device achieves a flat-top response for each channel, high channel isolation and background noise suppression.

Abstract: The present invention provides a photonic multi-bandgap structure, herein also referred to as photonic bandgap quasi-crystal (“PBQC”), that can direct light, having wavelength components within a selected passband (&Dgr;&lgr;), from an input port, to a predefined output port, while providing an integrating element for Planar Lightwave Circuts. A photonic bandgap quasi-crystal of the invention combines in a planar waveguide spectrally selective properties of gratings, focusing properties of elliptical mirrors, superposition properties of thick holograms, photonic bandgaps of periodic structures, and flexibility of binary lithography. A photonic structure of the invention can be utilized, for example, as an integrating spectrally sensitive element in a variety of optical devices that can include, but are not limited to, optical switches, optical multiplexer/demultiplexers, multi-wavelength lasers, and channel monitors in Wavelength Division Multiplexing (WDM) telecommunications system.