Low-loss 10-GHz-spaced tandem multi/demultiplexer with more than 1000 channels using a 1/spl times/5 interference multi/demultiplexer as a primary filter

A very large channel-count low-loss optical multi/demultiplexer with more than 1000 channels is described. It was achieved by cascading a 1/spl times/5 flat-top interference multi/demultiplexer as a primary filter and five 10 GHz-spaced 1/spl times/288 arrayed-waveguide gratings as secondary filters in a tandem configuration.