Applied Optoelectronics, Inc. Patent applications |
Patent application number | Title | Published |
20150295385 | SWITCHED RADIO FREQUENCY (RF) DRIVER FOR TUNABLE LASER WITH MULTIPLE IN-LINE SECTIONS - A tunable laser with multiple in-line sections generally includes a semiconductor laser body with a plurality of in-line laser sections each configured to be driven independently to generate laser light at a wavelength within a different respective wavelength range. The wavelength of the light generated in each of the laser sections may be tuned, in response to a temperature change, to a channel wavelength within the respective wavelength range. A switch module may be configured to couple a signal from a laser driver to a selected one of the plurality of in-line laser sections, wherein the signal modulates the laser light generated by the in-line laser section. The selected in-line section may be DC biased to a lasing state and the non-selected in-line sections may be DC biased to a non-lasing or transparent state. | 10-15-2015 |
20150245114 | OPTICAL NETWORKING UNIT (ONU) PACKAGING - A bidirectional optical subassembly (BOSA) optical networking unit (ONU) generally includes a BOSA housing. A tunable laser is located in the BOSA housing and is configured to generate a first optical signal for transmission at a first selected wavelength based on temperature control. The tunable laser is a distributed feedback (DFB) laser diode. A thermal management device is also located in the BOSA housing and is configured to provide the temperature control. A photo diode is further located in the BOSA housing and is configured to receive a second optical signal at a second selected wavelength. The BOSA housing comprises an alloy of stainless steel or an alloy of Kovar. | 08-27-2015 |
20150243558 | SCRIBE ETCH PROCESS FOR SEMICONDUCTOR LASER CHIP MANUFACTURING - An improved scribe etch process for semiconductor laser chip manufacturing is provided. A method to etch a scribe line on a semiconductor wafer generally includes: applying a mask layer to a surface of the wafer; photolithographically opening a window in the mask layer along the scribe line; etching a trench in the wafer using a chemical etchant that operates on the wafer through the window opening, wherein the chemical etchant selectively etches through crystal planes of the wafer to generate a V-groove profile associated with the trench; and cleaving the wafer along the etched trench associated with the scribe line through application of a force to one or more regions of the wafer. | 08-27-2015 |
20150188635 | PLUGGABLE OPTICAL TRANSCEIVER MODULE - A pluggable optical transceiver module for being plugged in a housing is provided. The housing has a cover and an elastic piece, and the cover has an accommodating space. One end of the elastic piece is connected to the cover while the other end has a first fastening portion. The first fastening portion is located on one side of the accommodating space. The pluggable optical transceiver module comprises a base and a sliding member. The base comprises a base body and a second fastening portion. The base body has a guide surface, and the second fastening portion is next to the guide surface. The base is for being plugged in the accommodating space, and the second fastening portion is fastened with the first fastening portion. The sliding member comprises a body section and a push section connected to each other. The body section is slidably disposed on the base. | 07-02-2015 |
20150055960 | HEATED LASER PACKAGE WITH INCREASED EFFICIENCY FOR OPTICAL TRANSMITTER SYSTEMS - A heated laser package generally includes a laser diode, a heating resistor and a transistor in a single laser package. The heating resistor and transistor form a heating circuit and may be located on a submount adjacent to the laser diode. The transistor is configured to control the drive current to the heating resistor and any additional heat generated by the transistor may contribute to the heating of the laser diode and thus increase the thermal efficiency of the system. The heated laser package may be used in a temperature controlled multi-channel transmitter optical subassembly (TOSA), which may be used in a multi-channel optical transceiver. The optical transceiver may be used in a wavelength division multiplexed (WDM) optical system, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON). | 02-26-2015 |
20140341580 | COMPACT MULTI-CHANNEL OPTICAL TRANSCEIVER MODULE - A compact multi-channel optical may include a multi-channel transmitter optical subassembly (TOSA), a multi-channel receiver optical subassembly (ROSA) and a circuit board configured and arranged to fit within a relatively small space. The multi-channel ROSA is spaced from the circuit board to allow circuit components to be mounted between the circuit board and the ROSA. The multi-channel ROSA may also be inverted and mounted proximate a transceiver top housing portion, for example, using an L-shaped ROSA support, to transfer heat from the ROSA to the transceiver housing portion. The optical transceiver may be used in a wavelength division multiplexed (WDM) optical system, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON). | 11-20-2014 |
20140341578 | ALIGNING AND DIRECTLY OPTICALLY COUPLING PHOTODETECTORS TO OPTICAL DEMULTIPLEXER OUTPUTS IN A MULTICHANNEL RECEIVER OPTICAL SUBASSEMBLY - A multi-channel receiver optical subassembly (ROSA) such as an arrayed waveguide grating (AWG), with outputs directly optically coupled to respective photodetectors such as photodiodes. In one embodiment, an AWG may be configured such that optical components of the AWG do not interfere with direct optical coupling, and the wire bonding points on the photodiodes may also be configured such that wire bonding does not interfere with direct optical coupling. The photodetectors may also be mounted on a photodetector mounting bar with a pitch sufficiently spaced to allow connection to floating grounds. A passive alignment technique may be used to determine the mounting locations on the photodetector mounting bar such that the photodetectors are aligned with the optical outputs. | 11-20-2014 |
20140241726 | TEMPERATURE CONTROLLED MULTI-CHANNEL TRANSMITTER OPTICAL SUBASSEMBLY AND OPTICAL TRANSCEIVER MODULE INCLUDING SAME - A temperature controlled multi-channel transmitter optical subassembly (TOSA) may be used in a multi-channel optical transceiver. The temperature controlled multi-channel TOSA generally includes an array of lasers optically coupled to an optical multiplexer, such as an arrayed waveguide grating (AWG), to combine multiple optical signals at different channel wavelengths. The lasers may be thermally tuned to the channel wavelengths by establishing a global temperature for the array of lasers and separately raising local temperatures of individual lasers in response to monitored wavelengths associated with the lasers. A temperature control device, such as a TEC cooler coupled to the laser array, may provide the global temperature and individual heaters, such as resistors adjacent respective lasers, may provide the local temperatures. The optical transceiver may be used in a wavelength division multiplexed (WDM) optical system, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON). | 08-28-2014 |
20140161459 | THERMALLY SHIELDED MULTI-CHANNEL TRANSMITTER OPTICAL SUBASSEMBLY AND OPTICAL TRANSCEIVER MODULE INCLUDING SAME - A thermally shielded multi-channel transmitter optical subassembly (TOSA) may be used in a multi-channel optical transceiver. The multi-channel TOSA generally includes an array of lasers optically coupled to an arrayed waveguide grating (AWG) to combine multiple optical signals at different channel wavelengths. A plurality of laser array thermal shields are thermally coupled to a temperature control device, such as a thermoelectric cooler (TEC), and thermally shield the respective lasers in the laser array in separate thermally shielded compartments. Each of the lasers may also be individually thermally controlled to provide a desired wavelength, for example, using a heater and/or cooler located in each thermally shielded compartment. The optical transceiver may be used in a wavelength division multiplexed (WDM) optical system, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON). | 06-12-2014 |
20140161457 | THERMALLY ISOLATED MULTI-CHANNEL TRANSMITTER OPTICAL SUBASSEMBLY AND OPTICAL TRANSCEIVER MODULE INCLUDING SAME - A thermally isolated multi-channel transmitter optical subassembly (TOSA) may be used in a multi-channel optical transceiver. The multi-channel TOSA generally includes an array of lasers optically coupled to an arrayed waveguide grating (AWG) to combine multiple optical signals at different channel wavelengths. The lasers, and possibly other components, are wire bonded to a thermal isolation bar. The thermal isolation bar provides an electrical connection to external circuitry and is thermally coupled to a temperature control device, such as a thermoelectric cooler (TEC). Thus, the thermal isolation bar electrically connects the lasers to the circuitry while preventing external heat from being conducted to the lasers from outside the TOSA. The optical transceiver may be used in a wavelength division multiplexed (WDM) optical system, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON). | 06-12-2014 |
20140161455 | TEMPERATURE CONTROLLED MULTI-CHANNEL TRANSMITTER OPTICAL SUBASSEMBLY AND OPTICAL TRANSCEIVER MODULE INCLUDING SAME - A temperature controlled multi-channel transmitter optical subassembly (TOSA) may be used in a multi-channel optical transceiver. The multi-channel TOSA generally includes an array of lasers optically coupled to an arrayed waveguide grating (AWG) to combine multiple optical signals at different channel wavelengths. A temperature control system may be used to control the temperature of both the array of lasers and the AWG with the same temperature control device, e.g., a thermoelectric cooler (TEC). The multi-channel optical transceiver may also include a multi-channel receiver optical subassembly (ROSA). The optical transceiver may be used in a wavelength division multiplexed (WDM) optical system, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON). | 06-12-2014 |
20140161394 | MULTI-CHANNEL OPTICAL TRANSCEIVER MODULE INCLUDING DUAL FIBER TYPE DIRECT LINK ADAPTER FOR OPTICALLY COUPLING OPTICAL SUBASSEMBLIES IN THE TRANSCEIVER MODULE - A multi-channel optical transceiver includes a multi-channel transmitter optical subassembly (TOSA), a multi-channel receiver optical subassembly (ROSA), and a dual fiber type direct link adapter directly linked to the multi-channel TOSA and the multi-channel ROSA with optical fibers. The dual fiber type direct link adapter is also configured to receive pluggable optical connectors, such as LC connectors, mounted at the end of fiber-optic cables including optical fibers for carrying optical signals to and from the transceiver. The dual fiber type direct link adapter thus provides the optical input and output to the transceiver for the optical signals received by the ROSA and transmitted by the TOSA. The multi-channel optical transceiver may be used in a wavelength division multiplexed (WDM) optical system, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON). | 06-12-2014 |
20140093244 | FILTERED LASER ARRAY ASSEMBLY WITH EXTERNAL OPTICAL MODULATION AND WDM OPTICAL SYSTEM INCLUDING SAME - A filtered laser array assembly generally includes an array of laser emitters coupled between external modulators and an arrayed waveguide grating (AWG). Each of the laser emitters emits light across a plurality of wavelengths including, for example, channel wavelengths in an optical communication system. The AWG filters the emitted light from each of the laser emitters at different channel wavelengths associated with each of the laser emitters. Lasing cavities are formed between each of the laser emitters and a back reflector coupled to an output of the AWG such that laser output from the laser emitters is provided at the respective channel wavelengths of the reflected, filtered light. The external modulators enable high speed modulation of the laser output. The modulated laser output may then be optically multiplexed to produce an aggregate optical signal including multiple channel wavelengths. | 04-03-2014 |
20130259485 | DISTORTION COMPENSATION CIRCUIT INCLUDING TUNABLE PHASE PATH - A distortion compensation circuit compensates for distortion generated by one or more non-linear elements such as a laser device and/or an optical fiber and may include a primary signal path for carrying an input signal and a secondary signal paths for generating distortion. The distortion compensation circuit may also include a controllable phase inverters and a tunable filter. For example, the secondary signal path may include a distortion generator to produce distortion products from the input signal and a signal controlled phase inverter that inverts the phase of the distortion products and a tunable filter that adjusts the phase of the frequency dependent distortion. The phase inversion and tunable filter may be controlled in response to control signals generated based on one or more parameters such as, for example, laser power, input RF channel loading, temperature, and fiber length. | 10-03-2013 |
20130223844 | EXTERNAL CAVITY LASER ARRAY SYSTEM AND WDM OPTICAL SYSTEM INCLUDING SAME - An external cavity laser array system may be used in a WDM optical system, such as a WDM-PON, for transmitting optical signals at multiple channel wavelengths. The system generally includes a plurality of laser emitters (e.g., gain chips) optically coupled to and separated from respective exit reflectors (e.g., tunable narrow-band reflectors), thereby forming an array of external cavity lasers with extended lasing cavities. The exit reflectors may be distributed Bragg reflectors (DBRs) located in the waveguides in an arrayed waveguide grating (AWG). The laser emitters emit a range of wavelengths including multiple channel wavelengths and the DBRs reflect a subset of channel wavelengths including at least a channel wavelength associated with the laser emitter such that lasing occurs at the subset of channel wavelengths. The AWG then filters the emitted laser light at the associated channel wavelengths. | 08-29-2013 |
20130188951 | OPTICALLY MATCHED LASER ARRAY COUPLING ASSEMBLY FOR COUPLING LASER ARRAY TO ARRAYED WAVEGUIDE GRATING - A laser array optical coupling assembly may be used to couple a laser array to an arrayed waveguide grating (AWG), for example, in an optical transmitter in a wavelength division multiplexed (WDM) optical communication system. The laser array optical coupling assembly may include an optical fiber tip array with polished optical fiber tips providing a reduced mode field diameter to improve coupling efficiency with the laser array. The laser array optical coupling assembly may also include a direct coupling of the laser array to the AWG with modified AWG inputs reducing the mode field diameter to improve coupling efficiency with the laser array. The laser array optical coupling assembly may be used, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON) or in other transmitters or transceivers in a WDM system capable of transmitting and receiving optical signals on multiple channel wavelengths. | 07-25-2013 |
20130084070 | OPTICAL TRANSCEIVER INCLUDING OPTICAL FIBER COUPLING ASSEMBLY TO INCREASE USABLE CHANNEL WAVELENGTHS - An optical transceiver may include an optical fiber coupling assembly for coupling optical fibers to transmitter and receiver sub-assemblies to increase the number of usable channel wavelengths by reducing an incident angle on a WDM filter without causing unwanted back reflection to a laser. In one example, the optical fiber coupling assembly may be used to increase the number of usable channel wavelengths between the L-band and the C-band. The optical transceiver may be used, for example, in an optical line terminal (OLT) and/or optical networking unit (ONU) in a wavelength division multiplexed (WDM) passive optical network (PON) capable of transmitting and receiving optical signals on multiple channel wavelengths. | 04-04-2013 |
20130039660 | OPTICAL TRANSCEIVER THAT MAINTAINS A BEND DIAMETER OF AN INTERNAL OPTICAL FIBER AND METHOD OF ASSEMBLING SAME - An optical transceiver includes an internal optical fiber coupled to optical sub-assemblies in the transceiver and is capable of maintaining a bend diameter of the internal optical fiber above a minimum bend diameter. The optical transceiver thus allows optical fiber to be used within a relatively small space within a housing of the optical transceiver without significant power loss in the optical signal carried on the optical fiber. The optical transceiver may be a small form-factor pluggable (SFP) transceiver used, for example, in an optical line terminal (OLT) and/or optical networking unit (ONU) in a wavelength division multiplexed (WDM) passive optical network (PON). | 02-14-2013 |
20130016977 | LASER ARRAY MUX ASSEMBLY WITH EXTERNAL REFLECTOR FOR PROVIDING A SELECTED WAVELENGTH OR MULTIPLEXED WAVELENGTHS - A laser array mux assembly generally includes an array of laser emitters coupled to an optical multiplexer, such as an arrayed waveguide grating (AWG), with an external partial reflector after the multiplexer. Each of the laser emitters may include a gain region that emits light across a range of wavelengths including, for example, channel wavelengths in an optical communication system. The AWG filters the emitted light from each of the laser emitters at different channel wavelengths associated with each of the laser emitters. The reflector reflects at least a portion of the filtered light such that lasing occurs at the channel wavelengths of the reflected light. The laser array mux assembly may be used to generate an optical signal at a selected channel wavelength or to generate and combine optical signals at multiple channel wavelengths. | 01-17-2013 |
20130016976 | EXTENDED CAVITY FABRY-PEROT LASER ASSEMBLY CAPABLE OF HIGH SPEED OPTICAL MODULATION WITH NARROW MODE SPACING AND WDM OPTICAL SYSTEM INCLUDING SAME - An extended cavity Fabry-Perot laser assembly provides relatively narrow mode spacing while allowing relatively high speed optical modulation. The extended cavity Fabry-Perot laser assembly generally includes an exit reflector physically separated from a laser emitter (e.g., a gain chip) to extend the lasing cavity and narrow the mode spacing while maintaining a relatively small gain region in the laser emitter capable of higher speed optical modulation. The extended cavity Fabry-Perot laser assembly may be used in a multi-channel transmitter in a wavelength division multiplexed (WDM) optical system that selects a channel wavelength for the transmitter from among multiple channel wavelengths emitted by the laser assembly. The narrow mode spacing may be less than a WDM channel width, and more specifically, may be less than a channel passband of an arrayed waveguide grating (AWG) or other filter used to select the channel wavelength. | 01-17-2013 |
20130016974 | WAVELENGTH-SELECTABLE LASER DEVICE AND APPARATUS AND SYSTEM INCLUDING SAME - A wavelength-selectable laser device generally includes an array of laser emitters and a filtered external cavity for filtering light emitted from the laser emitters and reflecting different wavelengths back to each of the laser emitters such that lasing occurs at different wavelengths for each of the laser emitters. Each laser emitter includes a gain region that emits light across a plurality of wavelengths including, for example, channel wavelengths in an optical communication system. The filtered external cavity may include a dispersive optical element that receives the light from each of the laser emitters at different angles and passes or reflects different wavelengths of the light at different angles such that only wavelengths associated with the respective laser emitters are reflected back to the respective laser emitters. By selectively emitting light from one or more of the laser emitters, one or more channel wavelengths may be selected for lasing and transmission. | 01-17-2013 |
20130016973 | WAVELENGTH-SELECTABLE LASER DEVICE PROVIDING SPATIALLY-SELECTABLE WAVELENGTH(S) - A wavelength-selectable laser device providing spatially-selectable wavelength(s) may be used to select one or more wavelengths for lasing in a tunable transmitter or transceiver, for example, in a wavelength division multiplexed (WDM) optical system such as a WDM passive optical network (PON). The wavelength-selectable laser device uses a dispersive optical element, such as a diffraction grating, to disperse light emitted from a laser emitter and to direct different wavelengths of the light toward a reflector at different spatial positions such that the wavelengths may be selected by allowing light to be reflected from selected spatial position(s) back into the laser emitter. Thus, the reflected light with a wavelength at the selected spatial position(s) is allowed to complete the laser cavity. | 01-17-2013 |
20130016972 | LASER MUX ASSEMBLY FOR PROVIDING A SELECTED WAVELENGTH - A laser mux assembly generally includes a back reflector selectively coupled to one of the input ports of an optical multiplexer, such as an arrayed waveguide grating (AWG), and at least one laser emitter coupled to an output port. The laser emitter may include a gain region that emits light across a plurality of wavelengths including, for example, channel wavelengths in an optical communication system. The emitted light is coupled into the output port and the AWG or optical multiplexer filters the emitted light from the laser emitter at different channel wavelengths. The back reflector reflects the filtered light at the respective channel wavelength such that lasing occurs at the channel wavelength(s) of the reflected, filtered light. The laser mux assembly may be used, for example, in a tunable transmitter, to generate an optical signal at a selected channel wavelength. | 01-17-2013 |
20130016971 | WDM OPTICAL SYSTEM AND METHOD INCLUDING MULTI-CHANNEL TRANSMITTERS WITH FILTERED OUTPUT FOR CHANNEL WAVELENGTH SELECTION - A wavelength division multiplexed (WDM) optical system generally includes multi-channel transmitters that transmit optical signals on multiple channel wavelengths in the WDM system. The output of the multi-channel transmitters is filtered to select a unique channel wavelength associated with each of the respective transmitters for multiplexing and transmission in the WDM optical system. One embodiment of a multi-channel transmitter includes a full-spectrum Fabry-Perot (FP) laser that emits light across a range of wavelengths including all of the system channel wavelengths. Another embodiment of a multi-channel transmitter includes a broadly-tunable FP laser that is tunable to emit light across different ranges of wavelengths including subsets of the system channel wavelengths. The WDM optical system may include an arrayed waveguide grating (AWG) for filtering and multiplexing the optical signals output from the transmitters. | 01-17-2013 |
20120288231 | LASER PACKAGE INCLUDING TILTED LASER AND METHOD OF USING SAME - In a laser package, a tilted laser causes laser light to be coupled into an optical fiber at an angle relative to a fiber axis of the optical fiber. The tilted laser emits laser light at an angle relative to a lens axis of a lens such that the lens directs and focuses the laser light at the angle relative to the fiber axis. Tilting the laser allows the laser light to be coupled into the optical fiber substantially parallel to or aligned with the core of the fiber while causing back reflection to be directed away from the laser, thereby improving coupling efficiency and minimizing feedback. The tilted laser may be coupled to an angle polished fiber, for example, in a laser package such as a TO can type laser package, a butterfly type laser package, or a TOSA type laser package. | 11-15-2012 |
20120183299 | SYSTEM AND METHOD FOR DISTORTION COMPENSATION IN RESPONSE TO FREQUENCY DETECTION - A distortion compensation circuit with frequency detection may be used with one or more non-linear elements, such as a laser, to compensate for frequency-dependent distortion generated by the non-linear element(s), for example, in broadband multichannel RF applications. Embodiments of the distortion compensation circuit may include a frequency detector circuit that detects changes in frequency loading conditions in the distortion compensation circuit such that distortion compensation may be adjusted to compensate for distortion under different frequency loading conditions. In a multichannel RF system with multiple channel operation modes, for example, the frequency detector circuit may detect changes in the frequency loading condition as a result of changing operation modes. | 07-19-2012 |
20120163832 | SYSTEM AND METHOD FOR DISTORTION COMPENSATION INCLUDING CONFIGUREABLE DELAY - A distortion compensation circuit including a configurable delay may be used with one or more non-linear elements, such as a laser, to compensate for distortion generated by the non-linear element(s), for example, in broadband RF applications. Embodiments of the distortion compensation circuit may include a primary signal path with a configurable delay segment and a secondary signal path including at least one distortion generator. The configurable delay segment may be selectively configured to provide different delay settings to accommodate different RF loading conditions such that the delayed RF signal on the primary signal path is aligned with the distortion products generated on the secondary signal path when combined to form an RF signal with distortion compensation. | 06-28-2012 |
20120141142 | DISTORTION COMPENSATION CIRCUIT INCLUDING ONE OR MORE PHASE INVERTIBLE DISTORTION PATHS - A distortion compensation circuit compensates for distortion generated by one or more non-linear elements such as a laser device and may include a primary signal path for carrying an input signal and one or more secondary signal paths for generating distortion. The distortion compensation circuit may also include one or more controllable phase inverters on at least one of the paths. For example, the secondary signal path may include a distortion generator to produce distortion products from the input signal and a signal controlled phase inverter that inverts the phase of the distortion products. The distortion generator and phase inverter may be combined as an invertible distortion generator. The phase inversion may be controlled in response to a phase inversion control signal generated based on one or more parameters such as temperature. | 06-07-2012 |
20120099870 | RECEPTACLE DIPLEXER - A pluggable bi-directional optical transceiver may include: a transmitting laser diode, for transmitting an optical signal according to a received electronic signal; an optical sensor, for receiving the optical signal and for generating the electronic signal according to the received optical signal; a fiber adapter, having a ceramic ferrule with two 8-degree end-face corners; a coupling portion, having three different openings for respectively receiving the transmitting laser diode, the optical sensor, and one end of the ceramic ferrule so an optical axis of a transmitting light of the transmitting laser diode is configured to deflect about 3.8 degrees with an optical axis of the ceramic ferrule; and an engaging portion, having a hollow shell for receiving another end of the ceramic ferrule and an engaging piece surrounding outside the shell for pluggably connecting an external fiber piece. | 04-26-2012 |
20100086309 | REDUCING CROSS-MODULATION IN MULTICHANNEL MODULATED OPTICAL SYSTEMS - A modulated optical system with cross-modulation compensation reduces or corrects cross-modulation that might occur at a target frequency range in a multichannel RF signal that modulates a laser. The system detects the cross-modulation, for example, by detecting an envelope of the RF signal or by detecting RF power fluctuations, generates a cross-modulation detection signal, filters the cross-modulation detection signal at the target frequency range, and imparts a compensating cross-modulation to the RF signal in response to the filtered cross-modulation detection signal. | 04-08-2010 |
20100086305 | REDUCING CROSS-MODULATION IN MULTICHANNEL MODULATED OPTICAL SYSTEMS - A modulated optical system with cross-modulation compensation reduces or corrects cross-modulation that might occur in a multichannel RF signal modulating a laser. The system detects the cross-modulation, for example, by detecting an envelope of the RF signal or by detecting RF power fluctuations, generates a cross-modulation detection signal, and imparts a compensating cross-modulation by adjusting a bias current of the laser in response to the cross-modulation detection signal. | 04-08-2010 |
20100008093 | Fixture for Securing Optoelectronic Packages for Wire and/or Component Bonding - Generally, a fixture for securing optoelectronic packages may be used to secure one or more optoelectronic packages for mounting one or more components and/or one or more wires to at least first and second mounting surfaces at different relative angles. The fixture is rotatable between at least first and second mounting positions with a top surface of the fixture being at respective first and second mounting angles relative to a horizontal plane. The fixture may be configured to secure the optoelectronic package(s) for positioning at different mounting angles to facilitate mounting the components and/or wires to the mounting surfaces at the different angles. The fixture may also be configured to be continuously adjustable over a range of angles between the first and second mounting angles. | 01-14-2010 |
20100007884 | Position Finding System and Method for Use in Aligning Laser Device with an Optical Fiber - A position finding system and method may be used to find an alignment position of a laser device relative to an optical fiber such as an angled optical fiber. The laser device may be positioned “off-axis” relative to the optical fiber such that light from the laser device is directed at an angle to an end of the optical fiber and coupled into the optical fiber. The position finding system and method may be used to find the alignment position by searching for relative high power positions at different angular orientations of the laser device and calculating coordinates of at least one alignment position from the coordinates of the relative high power positions. The relative high power positions may be positions at which the measured power coupled into the optical fiber by the laser is maximized. | 01-14-2010 |
20090310970 | NETWORK TIMING - The subject matter disclosed herein relates to synchronizing network timing. In one particular example, network timing may be synchronized using reflected signals. | 12-17-2009 |
20090310635 | WAVELENGTH LOCKER AND LASER PACKAGE INCLUDING SAME - A wavelength locker may include a first optical detector configured to detect light, wherein the first optical detector is at least partially transparent to the light. The wavelength locker may further include an optical interferometer optically coupled to the first optical detector and to a second optical detector. The optical interferometer is configured to selectively filter the light that passes through the first optical detector and the second optical detector detects the filtered light. An optical module or package may include the wavelength locker coupled to a laser for locking an emission wavelength of the laser. | 12-17-2009 |
20090290613 | EXTERNAL CAVITY LASER ASSEMBLY INCLUDING EXTERNAL CHIRPED EXIT REFLECTOR FOR IMPROVED LINEARITY - An external cavity laser assembly includes an external chirped exit reflector configured to reduce changes in reflectivity, thereby improving linearity. The chirped exit reflector may be configured to provide a reflectivity profile with a substantially flat peak portion, for example, as compared to the reflectivity profile of a uniform period fiber Bragg grating. The chirped exit reflector may also be configured such that an optical cavity length of the external cavity laser is shorter for higher wavelengths, thereby reducing wavelength fluctuations and changes in reflectivity caused by wavelength fluctuations. | 11-26-2009 |
20090278583 | CLIPPING CORRECTION SYSTEM AND METHOD FOR CORRECTING CLIPPED SIGNALS IN A RECEIVER - A system and method for restoring a clipped signal may be used in an optical receiver that detects a clipped modulated optical signal. The clipped modulated optical signal is detected to produce a clipped electrical signal including a series of clipped negative peaks and corresponding positive peaks. The clipped signal may be corrected by detecting at least one trigger peak preceding one or more clipped negative peaks to be restored and generating a replacement tip signal segment for the clipped negative peak(s) to be restored. The replacement tip signal segment may be combined with the clipped electrical signal such that the replacement tip signal segment coincides with a clipped end of the clipped negative peak to be restored to produce a restored negative peak. | 11-12-2009 |
20090237171 | REDUCING CROSS MODULATION IN MULTICHANNEL MODULATED OPTICAL SYSTEMS WITH ANTI-CLIPPING - A modulated optical system with anti-clipping reduces or corrects clipping that might occur in the laser as a result of negative spikes or peaks in a multichannel RF signal. The system generally detects an envelope of the RF signal to generate an anti-clipping signal that follows at least a portion of the envelope and prevents one or more negative peaks from causing clipping by adjusting a bias current in response to the anti-clipping signal. The system may also reduce cross modulation by clamping the anti-clipping signal at an anti-clipping limit during lower power periods of the RF signal. | 09-24-2009 |
20090202256 | LASER PACKAGE INCLUDING SEMICONDUCTOR LASER AND MEMORY DEVICE FOR STORING LASER PARAMETERS - A laser package may include a semiconductor laser and a memory device integrated into the laser package for storing parameters associated with the laser. The parameters may include laser manufacturing, operational and/or user parameters. For example, the semiconductor laser may be tunable and the memory device may store tuning parameter data. One example of the laser package is a tunable transmitter optical sub-assembly (TOSA) package. | 08-13-2009 |
20090196630 | Distortion Compensation Circuit Including One or More Phase Invertible Distortion Paths - A distortion compensation circuit compensates for distortion generated by one or more non-linear elements such as a laser device and may include a primary signal path for carrying an input signal and one or more secondary signal paths for generating distortion. The distortion compensation circuit may also include one or more controllable phase inverters on at least one of the paths. For example, the secondary signal path may include a distortion generator to produce distortion products from the input signal and a signal controlled phase inverter that inverts the phase of the distortion products. The distortion generator and phase inverter may be combined as an invertible distortion generator. The phase inversion may be controlled in response to a phase inversion control signal generated based on one or more parameters such as temperature. The secondary signal path may also include separate distortion sub-paths to produce frequency independent distortion products and frequency dependent distortion products. | 08-06-2009 |
20090196629 | DISTORTION COMPENSATION CIRCUIT AND METHOD BASED ON ORDERS OF TIME DEPENDENT SERIES OF DISTORTION SIGNAL - A distortion compensation circuit compensates for distortion generated by one or more non-linear elements such as a laser device. The distortion compensation circuit may be used in an optical transmitter, such as a laser transmitter used for forward path CATV applications. The distortion compensation circuit may include a primary signal path and a secondary signal path that receive an input signal. The secondary signal path produces distortion of a magnitude corresponding to the magnitude of, but at an opposite phase to, the distortion generated by the non-linear amplifier. The secondary signal path includes a plurality of distortion sub-paths with each of the distortion sub-paths configured to produce intermodulation distortion products of the same distortion order but for different frequency dependent orders in a time dependent series representative of the distortion produced by the non-linear amplifier. | 08-06-2009 |
20090176401 | Pluggable form factor release mechanism - Briefly, various embodiments of a pluggable form factor release mechanism are described. | 07-09-2009 |
20090080482 | GAIN-COUPLED DISTRIBUTED FEEDBACK SEMICONDUCTOR LASER INCLUDING FIRST-ORDER AND SECOND-ORDER GRATINGS - A gain-coupled distributed feedback (DFB) semiconductor laser includes a grating formed by grooves through at least a part of an active region of a laser cavity. The DFB laser may be configured with a substantially pure gain-coupled grating and may be configured to provide facet power asymmetry. The grating may include at least a first-order grating section and a second-order grating section. A lasing wavelength may be obtained at the Bragg wavelength of the second-order grating section by substantially eliminating index coupling in the grating. The first-order grating section may act as a reflector for the lasing wavelength, thereby producing asymmetric power distribution in the laser cavity. | 03-26-2009 |
20090041474 | PREDISTORTION CIRCUIT INCLUDING DISTORTION GENERATOR DIODES WITH ADJUSTABLE DIODE BIAS - A predistortion circuit provides a predistorted input signal that compensates for distortion generated by a non-linear amplifier such as a laser device. The predistortion circuit may be used in an optical transmitter designed for broadband applications, such as a laser transmitter used for forward path CATV applications. The predistortion circuit may include a primary signal path and a secondary signal path that receive an input signal. A second order distortion generator on the secondary signal path generates predistortion of a magnitude corresponding to the magnitude of, but at an opposite phase to, the distortion generated by the non-linear amplifier. The second order distortion generator includes diodes with an adjustable diode bias to control phase, magnitude and/or magnitude/phase versus frequency of the predistortion. | 02-12-2009 |
20090016683 | ANGLED FIBER FERRULE HAVING OFF-AXIS FIBER THROUGH-HOLE AND METHOD OF COUPLING AN OPTICAL FIBER AT AN OFF-AXIS ANGLE - An angle-polished optical fiber may be mounted relative to a laser at an off-axis angle to allow coupled light from a laser to be substantially aligned with the axis of the fiber core. An angled fiber ferrule may facilitate providing the off-axis angle when coupling the angle-polished optical fiber to a laser package. The angled fiber ferrule includes a through hole including at least a portion that is off-axis. The axis of the off-axis portion of the through hole is angled at the off-axis angle with respect to an axis of the ferrule body portion. | 01-15-2009 |
20090016389 | LASER DRIVE CIRCUIT AND METHOD PROVIDING HIGH LIMIT CLIPPING CORRESPONDING TO LOW LIMIT CLIPPING IN A LASER - A laser drive circuit may be used to induce high limit clipping corresponding to natural low limit clipping in a laser, such as a laser diode, to reduce even order distortion such as composite second order (CSO) distortion. A drive current input may be provided to the active region of the laser to produce a modulated optical output in response to the drive current input. The laser drive circuit may include a current clamp at the drive current input, which clamps the drive current to provide the high limit clipping. The current clamp may receive an input current including current from a RF signal provided by a RF source together with a bias current provided by a bias current source. | 01-15-2009 |
20080292324 | SYSTEMS AND METHODS FOR REDUCING CLIPPING IN MULTICHANNEL MODULATED OPTICAL SYSTEMS - A system for reducing clipping may be used between a multichannel RF source and a laser to reduce or correct clipping that might occur in the laser as a result of negative spikes or peaks in a multichannel RF signal. The system generally includes a clipping correction circuit that receives the multichannel RF signal and responsive to the RF signal, prevents one or more of the negative peaks in the RF signal from causing clipping. The clipping correction circuit may either detect an envelope of the RF signal and/or may detect one or more peaks in the RF signal. One or more negative peaks may be prevented from causing clipping by adjusting a bias current provided by a bias control circuit and/or by modifying the RF signal with one or more clipping correction pulses coinciding with one or more negative peaks. | 11-27-2008 |
20080292323 | SYSTEMS AND METHODS FOR REDUCING CLIPPING IN MULTICHANNEL MODULATED OPTICAL SYSTEMS - A system for reducing clipping may be used between a multichannel RF source and a laser to reduce or correct clipping that might occur in the laser as a result of negative spikes or peaks in a multichannel RF signal. The system generally includes a clipping correction circuit that receives the multichannel RF signal and responsive to the RF signal, prevents one or more of the negative peaks in the RF signal from causing clipping. The clipping correction circuit may either detect an envelope of the RF signal and/or may detect one or more peaks in the RF signal. One or more negative peaks may be prevented from causing clipping by adjusting a bias current provided by a bias control circuit and/or by modifying the RF signal with one or more clipping correction pulses coinciding with one or more negative peaks. | 11-27-2008 |
20080212637 | DISTRIBUTED FEEDBACK SEMICONDUCTOR LASER INCLUDING WAVELENGTH MONITORING SECTION - In general, a complex-coupled distributed feedback (DFB) semiconductor laser includes a grating formed by grooves through at least a part of an active region of a laser cavity. The complex-coupled DFB laser may be configured with a wavelength monitoring section and may be configured to provide facet power asymmetry. The wavelength monitoring section may include a second-order grating section configured to emit radiation (e.g., vertical radiation) from a side of the DFB laser for monitoring. | 09-04-2008 |