Wavelength dependent optical switch

A wavelength-selective switch, comprising:

• a plurality of input fibers, each propagating multiple optical wavelengths;
• a plurality of input collimating lenses, each of the plurality of input collimating lenses coupled to a corresponding one of the plurality of input fibers;
• a plurality of demultiplexers, each coupled to a corresponding one of the plurality of input collimating lenses, wherein each of the plurality of demultiplexers comprises a plurality of optical interference filters having a stack of layers with different dielectric constants to produce multiple free-space optical beams at different optical wavelengths;
• a free space optical switch coupled to the plurality of demultiplexers, the free space optical switch having free-space optical beam inputs and free-space optical beam outputs and an input array of mirrors that rotate in two axes;
• an output array of mirrors that rotate in two axes;
• and
• a plurality of multiplexers coupled to the free space optical switch, wherein each of the plurality of multiplexers comprises a plurality of optical interference filters having a stack of layers with different dielectric constants coupled to receive at least one of the multiple free-space optical beams from the free space optical beam outputs of the free space optical switch.