Wavelength-selective switch and integrated wavelength demultiplexer using stacked planar lightwave circuits

An optical network node, comprising:

• a first wavelength-selective switch, having at least one input port adapted to couple to at least one ingress fiber, the first wavelength-selective switch having a plurality of drop ports, and at least one output port;
• and
• a second wavelength-selective switch, having at least one input port coupled to the at least one output port of the first wavelength-selective switch, the second wavelength-selective switch having a plurality of add ports, and at least one output port;
• wherein the first wavelength-selective switch includes a stack of planar lightwave circuits having the plurality of add ports integrated therein, and the second wavelength-selective switch includes a stack of planar lightwave circuits having the plurality of drop ports integrated therein.

A method of producing a wavelength-selective switch, comprising:

• stacking a plurality of substantially identical first planar waveguide circuits, the first planar waveguide circuits having edge facets;
• stacking a second planar waveguide circuit, the second planar waveguide circuit different from the first planar waveguide circuits, with the plurality of first planar waveguide circuits, the second planar waveguide circuit having an edge facet;
• positioning a lens such that the first and second planar waveguide circuit edge facets are at a front focal plane of the lens, and the lens is operable to generate a spectrally resolved optical signal at a back focal plane of the lens;
• positioning a tilting micro-mirror array at the back focal plane of the lens, such that the tilting micro-mirror array is operable to reflect the spectral components;
• and
• coupling a fiber array to the second planar waveguide circuit.