The present invention relates to an optical device (101, 201, 305). The present invention may be implemented as optical artificial neurons. The optical device comprises an optically transmissive light-receiving device (102) which may be a photodiode, an optically transmissive light-emitting device (104, 304) such as a light-emitting diode, an optically transmissive processor (103) comprising a memory storage device (106). The light-emitting device and the light-receiving device are electrically connected to the processor which is configured to control the light-emitting device to emit an optical signal (307, 313) based on a first optical signal received by the light-receiving device. The optical device comprises an address which is transmitted with the optical signal. The address of may be recognized by the processor when processing a received optical signal and is used by the processor to determine to control the light-emitting device to emit an optical signal or not.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. An optical device comprising: an optically transmissive light-emitting device configured to allow at least portion of an optical signal to be transmitted through said optically transmissive light-emitting device; an optically transmissive light-receiving device, wherein said optical signal is received by said optically transmissive light-receiving device and at least a portion of said optical signal is transmitted through said optically transmissive light-receiving device; and an optically transmissive control unit electrically connected to said light-emitting device and to said light-receiving device, said optically transmissive control unit being configured to allow at least a portion of said optical signal to pass through the optically transmissive control unit; wherein the control unit is configured to control the light-emitting device to emit an optical signal based on at least said optical signal received by said light-receiving device. 2. The optical device according to claim 1, further comprising an optically transmissive storage device configured to store a unique address of said optical device. 3. The optical device according to claim 1, wherein said storage device is further configured to store a plurality of predefined unique addresses, each address corresponding to a respective optical device. 4. The optical device according to claim 1, wherein said control unit is configured to control said light-emitting device to emit an optical signal comprising information identifying said optical device. 5. The optical device according to claim 3, wherein if an address of a received optical signal corresponds to one of said plurality of predefined unique addresses, said control unit is configured to increment a property value by an amount based on a weight of said received optical signal. 6. The optical device according to claim 5, wherein if said property value exceeds a threshold value, said control unit is configured to control said light-emitting device to emit an optical signal. 7. The optical device according to claim 1, wherein said optical device is integrated in an optically transmissive medium such that optical signals may be received from all directions by said light-receiving device and such that optical signals may be emitted in all directions by said light-emitting device. 8. The optical device according to claim 1, wherein said optical device is integrated in a casing comprising an optically opaque portion arranged such that optical signals may be prevented from being received from at least one direction and such that optical signals may be prevented from being emitted in at least one direction. 9. A system comprising a plurality of optical devices according to claim 7, being arranged adjacent to each other in a housing. 10. A system comprising a plurality of optical devices according to claim 1, arranged such that an optical signal may propagate unguided from a first optical device to a second optical device. 11. The plurality of optical devices according to claim 10, arranged such that an optical signal may propagate unguided from said first optical device to a second optical device through a third optical device. 12. A method of controlling an optical device comprising: an optically transmissive light-emitting device configured to allow at least portion of an optical signal to be transmitted through said optically transmissive light-emitting device; an optically transmissive light-receiving device, wherein said optical signal is received by said optically transmissive light-receiving device and at least a portion of said optical signal is transmitted through said optically transmissive light-receiving device; an optically transmissive storage device; and an optically transmissive control unit electrically connected to and configured to control said light-emitting device, said light-receiving device and said storage device, said optically transmissive control unit and said optically transmissive storage device being configured to allow at least a portion of said optical signal to pass through the optically transmissive control unit and said optically transmissive storage device; said method comprising the steps of: receiving an optical signal comprising an address identifying a second optical device; determining if said address identifying a second optical device correspond to an address stored in said storage device; and if said address corresponds to said address stored in said storage device, incrementing a property value based on a weight of said received optical signal. 13. The method according to claim 12, wherein, if said property value exceeds a threshold value, controlling said light-emitting device to emit an optical signal.