# US 7,466,881 B1 · Optical switch > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,466,881 B1 - Document ID: US7466881B1 - Status: Granted - Kind: B1 - Application number: 11/827,766 - Filed: 2007-07-13 - Granted: 2008-12-16 - Earliest claimed: 2007-07-13 - Assignees: Hewlett-Packard Development Company, L.P. - Inventors: David A. Fattal; Jong-Souk Yoo - Web page: https://patentgrep.com/patent/US7466881B1 ## CPC - G02B 6/1225: {comprising photonic band-gap structures or photonic lattices} - B82Y 20/00: Nanooptics, e.g. quantum optics or photonic crystals - G02B 6/12007: {forming wavelength selective elements, e.g. multiplexer, demultiplexer} - G02B 6/125: Bends, branchings or intersections - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES ## Abstract An optical switch includes an optical source; a plurality of tunable optical resonators or tunable waveguides in optical communication with the optical source; and a tuning device configured to selectively route an optical beam from the optical source to at least one optical destination by tuning at least one of the optical resonators or tunable waveguides, in optical communication with at least one optical destination, to a wavelength characteristic of the optical beam. ## Claims ### Claim 1 An optical switch, comprising: an optical source; at least three interconnected tunable optical resonators or tunable waveguides, wherein a first tunable optical resonator or tunable waveguide is optically coupled to said optical source and each remaining tunable optical resonator or tunable waveguide is optically coupled to one of a plurality of respective optical destinations; and a tuning device configured to selectively route an optical beam from said optical source to at least one of said optical destinations by tuning at least said first tunable optical resonator or tunable waveguide and at least one of said remaining tunable optical resonators or tunable waveguides to a wavelength characteristic of said optical beam. ### Claim 2 (depends on 1) The optical switch of claim 1, wherein said tunable optical resonators are selected from the group consisting of: photonic crystal resonant cavities, ring resonators, Fabry-Perot cavities, mirror resonators, and combinations thereof. ### Claim 3 (depends on 1) The optical switch of claim 1, wherein said tunable waveguides each comprise an associated ring resonator. ### Claim 4 (depends on 1) The optical switch of claim 1, wherein said optical source is in optical communication with said first tunable optical resonator through at least one optical waveguide. ### Claim 5 (depends on 1) The optical switch of claim 1, wherein said tuning device is configured to selectively inject and deplete charge locally from at least a portion of each of said tunable optical resonators or tunable waveguides. ### Claim 6 (depends on 5) The optical switch of claim 5, wherein said tuning device comprises an electrical source. ### Claim 7 (depends on 5) The optical switch of claim 5, wherein said tuning device comprises at least one additional optical source configured to selectively direct optical beams to at least a portion of said tunable optical resonators or tunable waveguides to control an electrical charge at those resonators or tunable waveguides. ### Claim 8 An optical switch, comprising: a photonic crystal body having a first optical resonant cavity in communication with an optical source and a plurality of additional optical resonant cavities in communication with a respective plurality of optical destinations; and a tuning device configured to selectively route an optical beam from said optical source to at least one of said optical destinations by tuning said first optical resonant cavity and at least one of said additional optical resonant cavities to a characteristic wavelength of said optical beam. ### Claim 9 (depends on 8) The optical switch of claim 8, wherein said photonic crystal body comprises a substantially periodic variation between at least two materials having different indices of refraction. ### Claim 10 (depends on 9) The optical switch of claim 9, wherein each of said optical resonant cavities comprises at least one point defect in said substantially periodic variation. ### Claim 11 (depends on 8) The optical switch of claim 8, wherein said tuning device comprises at least one electrical source in electrical communication with said point defects, wherein said at least one electrical source is configured to selectively inject and deplete charge in said optical resonant cavities. ### Claim 12 (depends on 8) The optical switch of claim 8, wherein said tuning device comprises a plurality of optical sources configured to selectively inject and deplete charge optically in said optical resonant cavities. ### Claim 13 (depends on 8) The optical switch of claim 8, wherein said tuning device is configured to tune said optical resonant cavities by selectively altering temperature in said cavities. ### Claim 14 (depends on 8) The optical switch of claim 8, wherein said tuning device is configured to selectively tune said optical resonant cavities at a rate of at least 1 THz. ### Claim 15 A method of selectively routing an optical beam, comprising: providing at least three interconnected tunable optical resonators or tunable waveguides; providing an optical source in optical communication with at least one of said tunable optical resonators or tunable waveguides; providing a plurality of optical destinations, each said optical destination being in optical communication with a respective remaining tunable optical resonator or tunable waveguide; tuning a said tunable optical resonator or tunable waveguide that is in communication with said optical source to a characteristic wavelength of said optical source; and tuning a said tunable optical resonator or waveguide that is in optical communication with an intended destination to said characteristic wavelength. ### Claim 16 (depends on 15) The method of claim 15, wherein said tunable optical resonators are tuned by selectively injecting and depleting charge from said resonators. ### Claim 17 (depends on 16) The method of claim 16, wherein said charge is selectively injected and depleted using optical sources configured to selectively shine optical energy on said optical resonators. ### Claim 18 (depends on 15) The method of claim 15, wherein said tunable optical resonators are tuned by selectively altering a temperature of said resonators. ### Claim 19 (depends on 15) The method of claim 15, further comprising the step of tuning optical resonators in said plurality that are not in communication with said intended destination to a second wavelength separate and distinct from said characteristic wavelength of said optical source. ### Claim 20 (depends on 15) The method of claim 15, wherein tuning each said tunable waveguide comprises controlling a ring resonator associated with that tunable waveguide.