Patent ID: 7167650

Claim:
An optical demultiplexer for demultiplexing an optical signal having a plurality of wavelength channels, wherein a centre wavelength of each of said channels is separated by a predetermined channel spacing, comprising: (a) wavelength demultiplexing means for receiving the optical signal and for dividing the optical signal into a plurality of demultiplexed wavelength streams having a wavelength separation therebetween larger than the predetermined channel spacing and, wherein at least one of the demultiplexed wavelength streams has more than one wavelength channel for carrying data; (b) time domain demultiplexing means for receiving one of the plurality of demultiplexed wavelength streams and for dividing the one of the plurality of wavelength streams into a plurality of time domain demultiplexed signals each comprising the plurality of wavelength streams; and (c) optical filtering means for wavelength demultiplexing the time domain demultiplexed signals into separate wavelength channels.