Wavelength routing optical switch
View Patent ↗An optical switch for routing arbitrary wavelengths between optical fibers in optical networks. The optical switch may include a highly wavelength dispersive element together with a spatially dispersive element to separate the wavelengths. Broadband switch inputs and outputs may be provided for adding and dropping arbitrary wavelengths at each node of the network. Fiber demultiplexers and multiplexers may also be used to reduce the impact of mirror array yield on switch functionality.
1. An optical wavelength switch, comprising:
an input port to receive a first beam having a plurality of wavelengths including a first wavelength;
an add port to receive a second beam having the first wavelength;
a cross-connect switch to receive the first beam from the input port and to receive the second beam from the add port;
a wavelength dispersive element coupled to the cross-connect switch to receive the first beam from the cross-connect switch, the wavelength dispersive element to separate the plurality of wavelengths of the first beam into a plurality of free-space beams each having a separate wavelength, the free-space beams including a first free-space beam corresponding to the first wavelength and a second free-space beam corresponding to a second wavelength;
a mirror array coupled to the wavelength dispersive element to receive the plurality of wavelengths of the first beam, the mirror array comprising a plurality of mirrors, each mirror rotatable in two axes;
an output port to receive the second beam and the second free-space beam from the cross-connect switch; and
a drop port to receive the first free-space beam from the cross-connect switch, wherein the input port, the add port, the output port and the drop port being arranged in a two-dimensional manner.
2. The optical wavelength switch of claim 1 , wherein the mirror array comprises a one dimensional array of mirrors and wherein the cross-connect switch comprises two dimensional arrays of mirrors.
3. The optical wavelength switch of claim 2 , further comprising a beam expander disposed between the cross-connect switch and the wavelength dispersive element.
4. The optical wavelength switch of claim 1 , wherein the wavelength dispersive element comprises a grating.
5. The optical wavelength switch of claim 1 , further comprising a lens coupled between the wavelength dispersive element and the mirror array to focus each of the plurality of wavelengths to a different mirror of the mirror array.
6. The optical wavelength switch of claim 5 , wherein each mirror is configured to direct a particular wavelength of the plurality of wavelengths through the lens and wavelength dispersive element to at least one of an output fiber associated with the output port and a drop-port fiber.
7. The optical wavelength switch of claim 6 , further comprising:
an input fiber associated with the input port to propagate the first beam having the plurality of wavelengths; and
a first input lens coupled to the input fiber to receive the first beam and form an input collimated beam, the first input lens coupled propagate the input collimated beam to the cross-connect switch.
8. The optical wavelength switch of claim 6 , further comprising
an add fiber;
a second input lens coupled to the add fiber;
a drop fiber; and
a third input lens coupled to the drop fiber.
9. The optical wavelength switch of claim 8 , wherein the cross-connect switch is configured to switch at least one wavelength of the first beam from the input fiber to one of the output fiber and the drop fiber.
10. The optical wavelength switch of claim 1 , wherein the cross-connect switch comprises:
a first plurality of mirrors, each rotatable in two axes;
a second plurality of mirrors.
11. The optical wavelength switch of claim 10 , further comprising a lens array coupled between the first and second plurality of mirrors.
12. The optical wavelength switch of claim 1 , wherein the cross-connect switch comprises:
a plurality of mirrors having input mirrors and output mirrors; and
a fixed mirror coupled to the plurality of mirrors.
13. The optical wavelength switch of claim 12 , wherein the fixed mirror is curved.
14. The optical wavelength switch of claim 1 , wherein the cross-connect switch comprises a plurality of mirrors adjustable to accommodate beam angle and position changes over temperature.
15. The optical wavelength switch of claim 1 , further comprising a wavelength interleaver coupled to the wavelength dispersive element, the wavelength interleaver to interleave a group of the separate wavelengths of the plurality of free-space beams.