# US 7,412,123 B1 · Hybrid free space fiber backplane > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,412,123 B1 - Document ID: US7412123B1 - Status: Granted - Kind: B1 - Application number: 11/751,910 - Filed: 2007-05-22 - Granted: 2008-08-12 - Earliest claimed: 2007-05-22 - Assignees: Intel Corporation - Inventors: Tom Mader; Christine Krause; Hengju Cheng; Jamyuen Ko - Web page: https://patentgrep.com/patent/US7412123B1 ## CPC - G02B 6/43: Arrangements comprising a plurality of opto-electronic elements and associated optical interconnections - H05K 1/14: Structural association of two or more printed circuits (providing electric connection to or between printed circuits H05K1/11, H01R12/00) - H05K 1/0274: {Optical details, e.g. printed circuits comprising integral optical means (H05K1/0269 takes precedence; coupling light guides with opto-electronic components G02B6/42)} - H05K 2201/044: Details of backplane or midplane for mounting orthogonal PCBs - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract Briefly, in accordance with one or more embodiments, a backplane includes one or more optical links and is capable of receiving one or more circuit cards. Optical signals sent via the optical links may at least partially travel in a free space region between optical elements of the circuit cards and the optical links. Optical signals may also traverse the free space between optical links in the absence of a circuit card wherein the optical signal may travel to one or more other circuit cards on the backplane. As a result, in one or more embodiments a network between one or more of the circuit cards on the backplane may be automatically configured even in the absence of one or more circuit cards from the backplane. ## Claims ### Claim 1 A backplane system, comprising: a backplane capable of receiving one or more circuit cards to connect to the backplane; and one or more optical links disposed on the backplane, the optical links having one or more lenses disposed to couple light between an optical element of a circuit card coupled to the backplane wherein the light at least partially travels in free space between the optical element and a lens of an optical link; wherein one or more of the circuit cards are capable of being coupled in a ring type network, a token-ring type network, star type network, or a mesh type network, or combinations thereof, via one or more of the optical links. ### Claim 2 (depends on 1) A backplane system as claimed in claim 1, wherein the light is capable of traveling in free space between a first optical link and a second optical link in a location where a circuit card may be disposed on the backplane in the absence of the circuit card. ### Claim 3 (depends on 1) A backplane system as claimed in claim 1, further comprising a return optical link disposed on the backplane to couple one or more of the circuit cards in a ring type topology. ### Claim 4 (depends on 1) A backplane system as claimed in claim 1, wherein one or more of the optical links comprises single mode fiber or multimode fiber, or combinations thereof. ### Claim 5 (depends on 1) A backplane system as claimed in claim 1, wherein one or more optical elements of one or more of the circuit cards comprises a VCSEL, a PIN diode, or a photonic integrated circuit, or combinations thereof. ### Claim 6 (depends on 1) A backplane system as claimed in claim 1, wherein the optical links are capable of providing one or more redundant optical paths. ### Claim 7 (depends on 1) A backplane system as claimed in claim 1, wherein one or more of the circuit cards comprises a management module for the backplane system. ### Claim 8 (depends on 1) A backplane system as claimed in claim 1, wherein one or more of the circuit cards comprises a photonic integrated circuit capable of implementing wavelength division multiplexing, dense wavelength division multiplexing, or optical time division multiplexing, or combinations thereof. ### Claim 9 (depends on 1) A backplane system as claimed in claim 1, wherein one or more of the circuit cards are capable of implementing a pass through function, an optical switching function, or a routing function, or combinations thereof, of optical signals traveling via the one or more optical links. ### Claim 10 (depends on 1) A backplane system as claimed in claim 1, wherein one or more of the circuit cards comprises a server blade, a switch, a router, a storage card, a network access card, a RAID card, a Fibre Channel card, or a radio network card, or combinations thereof. ### Claim 11 A circuit card, comprising: a circuit disposed thereon; and one or more optical elements disposed thereon, the one or more optical elements being capable of communicating with the circuit and one or more other circuit cards via an optical link disposed in proximity to the circuit card, wherein at least a portion of the optical signal comprises light capable of traveling in a free space region between the optical link and the one or more optical elements without requiring a physical connection between the optical link and the one or more optical elements; wherein one or more of the optical elements are disposed on a photonic integrated circuit of the circuit card, the photonic integrated circuit being capable of implementing wavelength division multiplexing dense wavelength division multiplexing or optical time division multiplexing or combinations thereof. ### Claim 12 (depends on 11) A circuit card as claimed in claim 11, wherein one or more of the optical elements are disposed on a photonic integrated circuit. ### Claim 13 (depends on 10) A circuit card as claimed in claim 10, wherein one or more of the optical elements are disposed on a photonic integrated circuit, the photonic integrated circuit being capable of implementing a bandwidth aggregation function, a pass through function, a switching function, or a routing function, or combinations thereof, of one or more optical signals communicated between one or more of the optical elements and one or more optical links.