Wavelength routing optical switch
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 apparatus, comprising:
a free-space wavelength switch having a switch input and a switch output;
a fiber-coupled demultiplexer coupled to the switch input to separate one or more wavelengths corresponding to non-working ports of the free-space wavelength switch; and
an optical switch coupled to the demultiplexer to route the one or more wavelengths corresponding to non-working ports of the free-space wavelength switch from the demultiplexer to a free-space wavelength switch output without conversion of the wavelengths from optical signals into electrical signals.
2. The apparatus of claim 1 , wherein the free-space wavelength switch comprises a single one dimensional array of mirrors.
3. The apparatus of claim 1 , wherein the free-space wavelength switch and the optical switch are the same switch.
4. The apparatus of claim 1 , wherein the free-space wavelength switch comprises:
a cross-connect switch;
a wavelength dispersive element coupled to receive a beam having a plurality of wavelengths from the cross-connect switch, the wavelength dispersive element to separate the plurality of wavelengths of the beam into a plurality of free-space beams each having a separate wavelength; and
a mirror array coupled to the wavelength dispersive element to receive the plurality of wavelengths of the beam, the mirror array comprising a plurality of mirrors, each mirror rotatable in two axes.
5. The apparatus of claim 1 , wherein the free-space wavelength switch comprises:
an input fiber to propagate a plurality of wavelengths;
an input lens coupled to the input fiber to form an input collimated beam having the plurality of wavelengths;
an input array of add-port fibers to propagate the plurality of wavelengths;
an input array of lenses coupled to the add-port fibers to form a plurality of collimated add-port beams having the plurality of wavelengths;
an input array of drop-port fibers;
a free-space demultiplexer to spatially separate the plurality of wavelengths;
an array of mirrors coupled to the free-space demultiplexer, each mirror switching at least one of an input beam having one of the plurality of wavelengths to an output fiber, the input beam to a drop-port fiber and an add-port beam to an output fiber;
an output free-space multiplexer coupled to the array of mirrors to spatially combine two or more of the plurality of wavelengths; and
an output lens coupled to the output free-space multiplexer to focus the beam into the output fiber, wherein the output fiber propagates more than one wavelength;
an output array of lenses to focus the beam into the drop-port fiber.
6. The apparatus of claim 5 , wherein the array of mirrors is configured to independently change a selected drop port connection without disturbing a selected add-port connection and change the add-port connection without disturbing the drop-port connection.
7. An apparatus, comprising:
at least one input port;
a plurality of add-ports;
a plurality of drop-ports;
at least one output port; and
means for independently selecting a drop port of the plurality of drop ports to receive an input wavelength and an add port of the plurality of add ports to receive an output wavelength using a single one-dimensional array of mirrors and free-space optical beams.
8. The apparatus of claim 7 , further comprising:
means for independently changing a selected drop port connection without disturbing a selected add-port connection and changing the add-port connection without disturbing the drop-port connection.
9. An apparatus, comprising:
a free-space wavelength switch having a switch input and a switch output;
an optical switch having one or more inputs and one or more outputs; and
a fiber-coupled multiplexer coupled to the one or more optical switch outputs to add these outputs in place of wavelengths corresponding to non-working ports of the free-space wavelength switch.
10. The apparatus of claim 9 , wherein the free-space wavelength switch and the optical switch are the same switch.
11. The apparatus of claim 9 , wherein the free-space wavelength switch comprises a single one dimensional array of mirrors.
12. The apparatus of claim 9 , wherein the free-space wavelength switch comprises:
a cross-connect switch;
a wavelength dispersive element coupled to receive a beam having a plurality of wavelengths from the cross-connect switch, the wavelength dispersive element to separate the plurality of wavelengths of the beam into a plurality of free-space beams each having a separate wavelength; and
a mirror array coupled to the wavelength dispersive element to receive the plurality of wavelengths of the beam, the mirror array comprising a plurality of mirrors, each mirror rotatable in two axes.