Arrayed-wave guide grating multi/demultiplexer with loop-back optical paths

Abstract From the Canadian patent

An optical device is presented which is useful for optical signal transmission and switching systems by multiplexing and demultiplexing optical signals in looped optical paths consisting of a plurality of individual loop-back optical paths. The device is essentially a multi/demultiplexer having an arrayed waveguide grating disposed between a plurality of input sections and output sections which are joined by the plurality of individual loop-back optical paths. Because the modulated signals are looped back into the same optical paths using the same devices, problems of mismatching performance introduced by using different optical devices are avoided. The device processes individual optical …