Abstract: An airplane fuel level optical sensor using one side-emitting plastic optical fiber (SPOF) and two fluorescent plastic optical fibers (FPOFs) to detect the airplane fuel level without using any electrically conductive component or element placed inside the fuel tank. This dual-FPOF sensor is capable of achieving high resolution and high accuracy with a one-time calibration in the actual airplane's fuel tank environment. One embodiment of the dual-FPOF sensor uses one SPOF and two FPOFs to detect fuel level change based on the optical signal output from the two FPOFs. The sensor design uses large-diameter (core and cladding), lightweight, low-cost and high-durability plastic optical fiber, which is very desirable for airplane installation.

Abstract: Systems and methods that use a differential spectral liquid level sensor to measure the level of liquid in a reservoir (e.g., a fuel tank or other storage container). The use of a differential spectral liquid level sensor solves the problem of common-mode intensity variations (i.e., intensity variations not due to the level of the liquid) by having two different wavelengths propagate through the same optical path but have different spectral attenuations in the liquid. By determining the ratio of the received optical powers, common-mode intensity variations can be neutralized, thereby enhancing the accuracy of the received power reading and the resulting liquid level indication.

Abstract: A controller area network (CAN) comprising a plurality of CAN nodes that communicate via a CAN bus that comprises a fiber optical network. The fiber optical network uses a single fiber and a single wavelength for transmit and receive, and comprises a passive reflective optical star. The reflective optical star comprises an optical mixing rod having a mirror at one end. The other end of the reflective optical star is optically coupled to the transmitters and receivers of a plurality of optical-electrical media converters by way of respective high-isolation optical Y-couplers. Each CAN node produces electrical signals (in accordance with the CAN message-based protocol) which are converted into optical pulses that are broadcast to the fiber optical network. Those optical pulses are then reflected back to all CAN nodes by the reflective optical star.

Abstract: Systems and methods that use a passive differential optical sensor to measure the level of liquid in a reservoir (e.g., a fuel tank or other storage container). More specifically, the passive differential optical liquid level sensor solves the problem of common-mode intensity variations by employing three optical fibers that will be disposed vertically in the reservoir. The system comprises a side-emitting optical fiber having one end optically coupled to an optical source, a side-receiving optical fiber optically coupled to a first optical detector, and a total internal reflection optical fiber having one end optically coupled to the other end of the side-emitting optical fiber and another end optically coupled to a second optical detector. A computer or processor is configured to perform differential processing of the detected light and then determine the liquid level based on the differential processing results.

Abstract: A method, system, and apparatus are disclosed for a ruggedized photonic crystal (PC) sensor packaging. In particular, the present disclosure teaches a ruggedized packaging for a photonic crystal sensor that includes of a hermetic-seal high-temperature jacket and a ferrule that eliminate the exposure of the optical fiber as well as the critical part of the photonic crystal sensor to harsh environments. The disclosed packaging methods enable photonic crystal based sensors to operate in challenging environments where adverse environmental conditions, such as electromagnetic interference (EMI), corrosive fluids, large temperature variations, and strong mechanical vibrations, currently exclude the use of traditional sensor technologies.

Abstract: A method, system, and apparatus are disclosed for a ruggedized photonic crystal (PC) sensor packaging. In particular, the present disclosure teaches a ruggedized packaging for a photonic crystal sensor that includes of a hermetic-seal high-temperature jacket and a ferrule that eliminate the exposure of the optical fiber as well as the critical part of the photonic crystal sensor to harsh environments. The disclosed packaging methods enable photonic crystal based sensors to operate in challenging environments where adverse environmental conditions, such as electromagnetic interference (EMI), corrosive fluids, large temperature variations, and strong mechanical vibrations, currently exclude the use of traditional sensor technologies.

Abstract: An airplane fuel level optical sensor using one side-emitting plastic optical fiber (SPOF) and two fluorescent plastic optical fibers (FPOFs) to detect the airplane fuel level without using any electrically conductive component or element placed inside the fuel tank. This dual-FPOF sensor is capable of achieving high resolution and high accuracy with a one-time calibration in the actual airplane's fuel tank environment. One embodiment of the dual-FPOF sensor uses one SPOF and two FPOFs to detect fuel level change based on the optical signal output from the two FPOFs. The sensor design uses large-diameter (core and cladding), lightweight, low-cost and high-durability plastic optical fiber, which is very desirable for airplane installation.

Abstract: An optical network having at least one star coupler comprising transmit and receive optical mixers which are respectively optically coupled to transmitters and receivers of a plurality of optical-electrical media converters. Each optical-electrical media converter comprises a respective receiver optically coupled to the receive optical mixer by way of plastic optical fibers and a respective transmitter optically coupled to the transmit optical mixer by way of plastic optical fibers. The output plastic optical fibers attached to an output face of the receive optical mixer have a diameter less than the diameter of the input plastic optical fibers attached to an input face of the receive optical mixer.

Abstract: A process for polishing the end face of a plastic optical fiber (POF) to produce a mirror smooth surface without any defect. Smooth POF end faces reduce the optical coupling loss when two plastic optical fibers are connected. The polishing process can be used to produce POF end faces which are recessed relative to the adjacent end face of a ferrule surrounding the fiber. When the ends of two ferrules are inserted in a connector designed to align the end faces of the ferrules while allowing those end faces to abut each other, the confronting recessed POF end faces will be separated by an air gap.

Abstract: An optical network having at least one star coupler comprising transmit and receive optical mixers which are respectively optically coupled to transmitters and receivers of a plurality of optical-electrical media converters. Each optical-electrical media converter comprises a respective receiver optically coupled to the receive optical mixer by way of plastic optical fibers and a respective transmitter optically coupled to the transmit optical mixer by way of plastic optical fibers. The output plastic optical fibers attached to an output face of the receive optical mixer have a diameter less than the diameter of the input plastic optical fibers attached to an input face of the receive optical mixer.

Abstract: Systems, methods, and apparatus for an optical sub-assembly (OSA) are disclosed. In one or more embodiments, the disclosed apparatus involves a package body, and a lock nut, where a first end of the lock nut inserted into a first cavity of the package body. The apparatus further involves a transistor outline (TO) can, where a first end of the TO can is inserted into a second cavity of the package body. Also, the apparatus involves an optical fiber, where a portion of the jacket from an end of the optical fiber is stripped off, thereby exposing bare optical fiber at the end of the optical fiber. The end of the optical fiber is inserted into a second end of the lock nut such that the bare optical fiber passes into the package body and at least a portion of the bare optical fiber is inserted into the TO can cavity.

Abstract: A process for polishing the end face of a plastic optical fiber (POF) to produce a mirror smooth surface without any defect. Smooth POF end faces reduce the optical coupling loss when two plastic optical fibers are connected. The polishing process can be used to produce POF end faces which are recessed relative to the adjacent end face of a ferrule surrounding the fiber. When the ends of two ferrules are inserted in a connector designed to align the end faces of the ferrules while allowing those end faces to abut each other, the confronting recessed POF end faces will be separated by an air gap.

Abstract: Systems, methods, and apparatus for a data bus-in-a-box (BiB) are disclosed. The system involves an electrical box, and at least one optical connector located on the box. The system further involves at least one mother board housed inside of the box, and comprising a transmit side comprising at least one transmit optical media converter (OMC) tile, and a receive side comprising at least one receive OMC tile. Also, the system involves first receive optical fibers that are each connected from at least one receive OMC tile to a receive coupler; and a second receive optical fiber connected from the receive coupler to one of the optical connectors. Further, the system involves first transmit optical fibers that are each connected from at least one transmit OMC tile to a transmit coupler; and a second transmit optical fiber connected from the transmit coupler to at least one of the optical connectors.

Abstract: An optical network having at least one star coupler comprising transmit and receive optical mixers which are respectively optically coupled to transmitters and receivers of a plurality of optical-electrical media converters. Each optical-electrical media converter comprises a respective receiver optically coupled to the receive optical mixer by way of plastic optical fibers and a respective transmitter optically coupled to the transmit optical mixer by way of plastic optical fibers. The output plastic optical fibers attached to an output face of the receive optical mixer have a diameter less than the diameter of the input plastic optical fibers attached to an input face of the receive optical mixer.

Abstract: Systems and methods that use an optical impedance sensor that eliminates electricity for measuring fuel quantity in fuel tanks. The optical impedance sensor comprises two optical fibers spaced apart inside a meniscus tube, one to transmit light along its length and the other to receive light along its length. The meniscus tube minimizes the sloshing of fuel level. The fuel level in the tank modulates the optical impedance between the two optical fibers, resulting in changes in the total light received by an optical detector. Depending on fuel tank height, the optical impedance sensor may comprise different embodiments in which the detection apparatus shapes the light to be unidirectional (emitted and collected only on one side of the fiber) or omnidirectional (all directions).

Abstract: A method, system, and apparatus are disclosed for a ruggedized photonic crystal (PC) sensor packaging. In particular, the present disclosure teaches a ruggedized packaging for a photonic crystal sensor that includes of a hermetic-seal high-temperature jacket and a ferrule that eliminate the exposure of the optical fiber as well as the critical part of the photonic crystal sensor to harsh environments. The disclosed packaging methods enable photonic crystal based sensors to operate in challenging environments where adverse environmental conditions, such as electromagnetic interference (EMI), corrosive fluids, large temperature variations, and strong mechanical vibrations, currently exclude the use of traditional sensor technologies.

Abstract: A method, system, and apparatus are disclosed for a ruggedized photonic crystal (PC) sensor packaging. In particular, the present disclosure teaches a ruggedized packaging for a photonic crystal sensor that includes of a hermetic-seal high-temperature jacket and a ferrule that eliminate the exposure of the optical fiber as well as the critical part of the photonic crystal sensor to harsh environments. The disclosed packaging methods enable photonic crystal based sensors to operate in challenging environments where adverse environmental conditions, such as electromagnetic interference (EMI), corrosive fluids, large temperature variations, and strong mechanical vibrations, currently exclude the use of traditional sensor technologies.

Abstract: An optical connector comprising a connecting structure, an optical receiver located within the connecting structure, an optical transmitter located within the connecting structure, and a heat sink located within the connecting structure. The heat sink is configured to conduct heat away from the optical receiver and the optical transmitter. The optical receiver and the optical transmitter are thermally connected to the heat sink.

Abstract: Systems, methods, and apparatus for an optical sub-assembly (OSA) are disclosed. In one or more embodiments, the disclosed apparatus involves a package body, and a lock nut, where a first end of the lock nut inserted into a first cavity of the package body. The apparatus further involves a transistor outline (TO) can, where a first end of the TO can is inserted into a second cavity of the package body. Also, the apparatus involves an optical fiber, where a portion of the jacket from an end of the optical fiber is stripped off, thereby exposing bare optical fiber at the end of the optical fiber. The end of the optical fiber is inserted into a second end of the lock nut such that the bare optical fiber passes into the package body and at least a portion of the bare optical fiber is inserted into the TO can cavity.

Abstract: Systems and methods that use an optical impedance sensor that eliminates electricity for measuring fuel quantity in fuel tanks. The optical impedance sensor comprises two optical fibers spaced apart inside a meniscus tube, one to transmit light along its length and the other to receive light along its length. The meniscus tube minimizes the sloshing of fuel level. The fuel level in the tank modulates the optical impedance between the two optical fibers, resulting in changes in the total light received by an optical detector. Depending on fuel tank height, the optical impedance sensor may comprise different embodiments in which the detection apparatus shapes the light to be unidirectional (emitted and collected only on one side of the fiber) or omnidirectional (all directions).