Abstract: A method for modifying a low-cost small form factor pluggable optical-electrical bidirectional transceiver (hereinafter “SFP transceiver”) by converting the SFP transceiver into a dual-in-line package. Such conversion enables the SFP transceiver to be soldered directly on a printed circuit board of a line replaceable unit of an avionics system, thereby eliminating the concern that the SFP transceiver may become detached due to vibration during aircraft operation. The method also includes a sealing process to protect the contact pads on the SFP transceiver, thereby eliminating any concern that the contact pads could corrode due to long-term moisture and humidity exposure. The product of the method is a ruggedized SFP transceiver capable of withstanding the rigors of operating in a harsh avionics environment onboard an aircraft.

Abstract: A fuel sensing system utilizes a fiber optic sensor comprising a membrane made of a direct band gap semiconductor material (such as gallium arsenide) that forms an optical cavity with an optical fiber inside a hermetically sealed sensor package located at the bottom of a fuel tank. The optical fiber inside the fuel tank is not exposed to the fuel. The optical cavity formed by the bottom surface of the membrane and the surface of the distal end of the internal optical fiber is capable of behaving as a Fabry-Pérot interferometer. Multiple light sources operating at different wavelengths and multiple spectrometers can be coupled to the confronting surface of the membrane via the optical fiber inside the fuel tank, a hermetically sealed fiber optic connector that passes through the wall of the fuel tank, and a fiber optic coupler located outside the fuel tank.

Abstract: A free-space laser communication system for bidirectional transmission of telemetry data in Gigabit Ethernet (GBE) protocol using a dual atmospheric effect mitigation approach. This free-space bidirectional GBE laser communication system utilizes an Optical Combining Receiver Array and a Framer/Forward Error Correction/Interleaver (FFI) device to mitigate the combined effects of atmospheric turbulence and channel fading. Since the FFI device is designed for Synchronous Optical Network (SONET) protocol, an intelligent (or smart) media converter is used to convert GBE telemetry data to SONET frames, which enables the FFI device to perform an error correction algorithm and provide a seamless error-free GBE laser communication link for distance over a kilometer. This bidirectional laser communication system can be implemented with low-cost commercially available components.

Abstract: A fuel sensing system utilizes a fiber optic sensor comprising a membrane made of a direct band gap semiconductor material (such as gallium arsenide) that forms an optical cavity with an optical fiber inside a hermetically sealed sensor package located at the bottom of a fuel tank. The optical fiber inside the fuel tank is not exposed to the fuel. The optical cavity formed by the bottom surface of the membrane and the surface of the distal end of the internal optical fiber is capable of behaving as a Fabry-Pérot interferometer. Multiple light sources operating at different wavelengths and multiple spectrometers can be coupled to the confronting surface of the membrane via the optical fiber inside the fuel tank, a hermetically sealed fiber optic connector that passes through the wall of the fuel tank, and a fiber optic coupler located outside the fuel tank.

Abstract: An apparatus comprises a substrate having a type of conductivity, an intrinsic region above the substrate, and a metal layer on a portion of the surface of the intrinsic region. The intrinsic region has a surface. The metal layer may have a thickness that is configured to allow a plurality of photons to pass through the metal layer into the intrinsic region and form a rectifying contact with the intrinsic region.

Abstract: An apparatus comprises an optical transmitter; an optical detector configured to receive optical signals from an optical fiber; an optical splitter having a first port, a second port coupled to the optical detector by the optical fiber, and a third port coupled to the optical transmitter; and a two stage amplifier system connected to an output of the optical detector. An input surface of the optical detector may have a diameter that is substantially equal to a diameter of a core in the optical fiber. The diameter of the input surface of the optical detector reduces capacitance and reduces signal distortion. The optical splitter may be configured to receive a first optical signal at the first port. The optical splitter may be configured to send the first optical signal to the second port and send a second optical signal received at the third port to the first port.

Abstract: Systems, methods, and a vehicle are disclosed to enable wireless optical communications. A wireless optical transceiver includes transmitter light source configured to transmit a first optical signal at a first wavelength via a first ball lens to generate a distributed first optical signal. The distributed first optical signal is configured to be received by a remote receiver via a first line-of-sight transmission. A detector is configured to receive a focused second optical signal at a second wavelength via a second ball lens. A controller is operably coupled to the light source and to the detector. The controller is configured to receive outgoing data and to generate a first electrical signal configured to modulate the first optical signal to transmit the outgoing data. The controller also is configured to receive a second electrical signal from the detector and to demodulate the second electrical signal to generate incoming data.

Abstract: An apparatus includes an enclosure configured to contain at least one optoelectronic device and to interface the at least one optoelectronic device to a polymer-clad silica (PCS) optical fiber. The enclosure includes a first section that includes a base portion and a wall portion. The wall portion is coupled to the base portion. The wall portion defines an open-ended slot that is configured to receive a first portion of a PCS optical fiber lead extending through the wall portion. A second section is configured to sealingly engage a first edge of the wall portion and the first portion of the PCS optical fiber lead. Passive alignment of PCS optical fiber leads to optoelectronic devices inside the package is accomplished using special designed precision mold ceramic block with integral U-grooves.

Abstract: An apparatus includes an enclosure configured to contain at least one optoelectronic device and to interface the at least one optoelectronic device to a polymer-clad silica (PCS) optical fiber. The enclosure includes a first section that includes a base portion and a wall portion. The wall portion is coupled to the base portion. The wall portion defines an open-ended slot that is configured to receive a first portion of a PCS optical fiber lead extending through the wall portion. A second section is configured to sealingly engage a first edge of the wall portion and the first portion of the PCS optical fiber lead. Passive alignment of PCS optical fiber leads to optoelectronic devices inside the package is accomplished using special designed precision mold ceramic block with integral U-grooves.

Abstract: A fiber cable distortion detection system includes a broadband source, an optical source fiber disposed in optical communication with the broadband source, an optical fiber under test (FUT) disposed in optical communication with the optical source fiber and an optical spectrum analyzer disposed in optical communication with the optical source fiber. The system combines the refection of the distortion with the reflection from the source/FUT interface using a 1×2 fiber coupler, the location of the distortion is precisely determined with high resolution by the spectrum of the combined signal. The system is miniaturized to the size of a hand-held device suitable for use in airplane cable plant installation or in an environment where space is limited.

Abstract: Systems, methods, and a vehicle are disclosed to enable wireless optical communications. A wireless optical transceiver includes transmitter light source configured to transmit a first optical signal at a first wavelength via a first ball lens to generate a distributed first optical signal. The distributed first optical signal is configured to be received by a remote receiver via a first line-of-sight transmission. A detector is configured to receive a focused second optical signal at a second wavelength via a second ball lens. A controller is operably coupled to the light source and to the detector. The controller is configured to receive outgoing data and to generate a first electrical signal configured to modulate the first optical signal to transmit the outgoing data. The controller also is configured to receive a second electrical signal from the detector and to demodulate the second electrical signal to generate incoming data.

Abstract: A method for providing an improved interconnection between an optical fiber and an optical package is described. The method includes inserting an end of the fiber through a feed through tube and into a main body of the optical package, a portion of the fiber proximate the end being metalized, attaching the metalized portion of the fiber within the main body of the optical package, a portion of the metalized fiber remaining within the feed through tube, inserting a stopping device into the feed through tube, melting solder within the feed through tube, in an area between the stopping device and the main body of the optical device, the area containing metalized fiber, compressing the melted solder using the stopping device, removing the stopping device from the feed through tube after the solder has solidified, and attaching a jacket associated with the optical fiber within the feed through tube.

Abstract: A laser cavity is provided by a reflecting spherical substrate with an array of emitters having a mode size. Each emitter has an axis aligned with a radius of the spherical substrate. A single mode waveguide is aligned with the array at an optical coupling distance less than the radius of the spherical substrate. A reflector substantially coincident with an end of the waveguide combines with the reflecting spherical substrate as a cavity.

Abstract: An apparatus comprises an optical transmitter; an optical detector configured to receive optical signals from an optical fiber; an optical splitter having a first port, a second port coupled to the optical detector by the optical fiber, and a third port coupled to the optical transmitter; and a two stage amplifier system connected to an output of the optical detector. An input surface of the optical detector may have a diameter that is substantially equal to a diameter of a core in the optical fiber. The diameter of the input surface of the optical detector reduces capacitance and reduces signal distortion. The optical splitter may be configured to receive a first optical signal at the first port. The optical splitter may be configured to send the first optical signal to the second port and send a second optical signal received at the third port to the first port.

Abstract: An apparatus comprises a substrate having a type of conductivity, an intrinsic region above the substrate, and a metal layer on a portion of the surface of the intrinsic region. The intrinsic region has a surface. The metal layer may have a thickness that is configured to allow a plurality of photons to pass through the metal layer into the intrinsic region and form a rectifying contact with the intrinsic region.

Abstract: A fiber cable distortion detection system includes a broadband source, an optical source fiber disposed in optical communication with the broadband source, an optical fiber under test (FUT) disposed in optical communication with the optical source fiber and an optical spectrum analyzer disposed in optical communication with the optical source fiber. The system combines the refection of the distortion with the reflection from the source/FUT interface using a 1×2 fiber coupler, the location of the distortion is precisely determined with high resolution by the spectrum of the combined signal. The system is miniaturized to the size of a hand-held device suitable for use in airplane cable plant installation or in an environment where space is limited.

Abstract: More cost-effective fiber optic interface modules, such as fiber optic transmitter modules and fiber optic receiver modules, are provided that meet the high performance requirements demanded by avionics and other specialized applications over a wide range of temperatures and other environmental conditions. The fiber optic interface module includes a printed wiring board having a pair of outwardly extending arms that define a notch therebetween. The fiber optic interface module also includes an integrated circuit mounted upon a medial portion of the printed wiring board and an optical subassembly. The optical subassembly includes a receptacle and an optoelectronic device, such as a light source or a detector. The receptacle generally defines an internal cavity for receiving the optoelectronic device and a pair of slots proximate the internal cavity.

Abstract: An optical subassembly comprises a micro-optical bench and a corresponding molded device submount having an optical detector, LED, or laser diode mounted thereon. The optical bench is a semiconductor wafer having one or more grooves etched therein. A submount groove is designed to receive a cooperating ridge on a bottom surface of the molded device submount so as to limit the movement of the submount on the optical bench. An optical fiber is secured in an alignment groove and secured to the optical bench. To complete the subassembly, it is only necessary to set the axial distance between the optical detector, LED, or laser diode and a distal end of the optical fiber. A fiber stop incorporated into the micro-optical bench automatically adjusts the axial positioning of the distal end of the fiber to the optical detector, LED, or laser diode. In addition, a hermetically sealed package is provided with a faceplate that is secured to the package.

Abstract: A method and apparatus for aligning an optical fiber (120) with an optoelectronic hybrid device (112) and locking the optical fiber in the aligned position are disclosed. A fiber coated with an external layer of gold is threaded through a solder preform (130). The optical fiber (120) rests upon a ceramic substrate (104). The ceramic substrate also supports a device submount (108) that houses the optoelectronic device (112). The ceramic substrate (104) supports a resistor/heater formed of a thin film of nickel-chromium alloy (604). The resistor/heater supports a pad (609) formed of a layer of nickel (610) and a layer of gold (612). Located atop the pad (609) is the solder preform (130). Precise control of heating is provided by applying a predetermined voltage to the resistor/heater (122) for precise time periods, thereby eliminating the necessity of making temperature measurements during heating. As the resistor/heater (122) is energized, the solder preform is liquefied.