Patent ID: 7212704

Claim:
An apparatus comprising: an input port for launching an input signal including a plurality of wavelength channels; an input dispersive element for demultiplexing the input signal into wavelength channels; at least one colourless output port, each colourless output port for outputting a respective multiplexed output signal containing a combination of all wavelength channels switched to that colourless output port; at least one output dispersive element, each outgoing dispersive element for multiplexing the wavelength channels switched to a respective colourless output port into a respective multiplexed output signal; a plurality of coloured output ports, each for outputting only a respective predetermined demultiplexed wavelength channel switched to that coloured output port; an optical element associated with the plurality of coloured output ports; a wavelength selective arrangement adapted to selectively switch each of the plurality of wavelength channels of the input signal to a respective one of: a) the at least one output dispersive element for multiplexing the selected wavelengths, and directing the multiplexed output signal to a selected colourless output port; b) the optical element, which then routes the demultiplexed wavelength to the coloured output port of the plurality of coloured output ports that outputs that wavelength.