A device employing at least one wavelength sieve/combiner that operates on
discrete wavelength units and is optically interposed between an array of
fibers and an array of micro mirrors which may be configured to act as in
a multiplexing mode, a demultiplexing mode, a broadcast mode, and
combinations of such modes. Each wavelength sieve/combiner can split a
wavelength division multiplexed (WDM) beam into various discrete
wavelength unit beams, combine various discrete wavelength unit beams
into a WDM beam, or cause multiple copies of part or all of the
wavelengths to be supplied as outputs. Typically, each fiber is
associated with one wavelength sieve/combiner. Preferably, the beams
between a wavelength sieve/combiner and the micro mirror array should be
converging to the plane of the micro mirror array.