Abstract: A multi-layer feedthrough structure for use in optoelectronic equipment. The feedthrough structure is composed of multiple stacked ceramic layers that together form a multi-layer platform. The multi-layer platform bisects the base portion of a header assembly that is located within the transmitter optical subassembly such that an interior portion of the multi-layer platform is located within the header assembly and an exterior portion is disposed outside. Each layer contains at least a portion of a plurality of conductive pathways that extend from the exterior to the interior portion of the multi-layer platform. A top insulating layer enables the conductive pathways to pass from the exterior to the interior portion of the platform without electrically contacting the header assembly base. The conductive pathways serve as electrical interconnects between components located within the header assembly and structures outside thereof.

Abstract: A small form factor transceiver module that incorporates an externally modulated laser (EML). The transceiver module has a transmitter optical subassembly with a header assembly having a base with a platform extending through. The platform has a plurality of conductive traces extending through the platform for making connections on both sides of the base. A thermoelectric cooler (TEC) is used to dissipate heat from a laser within the header assembly. The TEC dissipates heat sufficiently to allow the EML to be used in the header assembly. In this manner, EMLs can be used in relatively small optical devices, including small form factor transceivers that comply with the XFP standard. The XFP modules with EMLs can be used for longer links than XFPs without EMLs. In addition, EMLs can be stabilized using TECs so that XFP modules can be used for DWDM-type applications.

Abstract: An optical transceiver module having a multiplexing analog control interface. The optical transceiver module comprises a controller and integrated post-amplifier/laser driver, which are included on a printed circuit board associated with the module. Transmitting and receiving optical sub-assemblies are also included in the module. A time division multiplexing analog control signal interface interconnects the controller with the integrated post-amplifier/laser driver. Digital control signals produced by the controller are converted and combined into a multiplexed analog control signal and transmitted via the interface to the integrated post-amplifier/laser driver. After receipt by the integrated post-amplifier/laser driver, the multiplexed analog control signal is divided into discrete analog control signals and forwarded to a plurality of control devices that use the control signals to modify a plurality of operating parameters of the transceiver module.

Abstract: An optical transceiver module having digital control of laser current peaking is disclosed. The optical transceiver module comprises a controller and integrated post-amplifier/laser driver, which are included on a printed circuit board disposed in the module. Transmitting and receiving optical sub-assemblies are also disposed in the module. A digital signal interface interconnects the controller with the integrated post-amplifier/laser driver. Digital control signals produced by the controller are transmitted via the digital signal interface to the integrated post-amplifier/laser driver, where they are converted to analog control signals. The analog control signals are forwarded to control components responsible for governing the electrical current supplied to the laser of the transmitting optical sub-assembly. The laser current is intermittently peaked by the control signal in order to hasten the transition from light to no-light emission, thereby improving laser response and performance.

Abstract: A transistor header assembly for use in transmitter optical subassemblies of optical transceivers. The header assembly has a base with a platform extending through. The platform has a conductive trace extending through the platform for making connections on both sides of the base. A thermoelectric cooler (TEC) is used to dissipate heat from a laser within the header assembly. The TEC dissipates heat sufficiently to allow an externally modulated laser (EML) to be used in the header assembly. In this manner, EMLs can be used in relatively small optical devices, including small form factor transceivers that comply with the XFP standard. The XFP modules with EMLs can be used for longer links than XFPs without EMLs. In addition, EMLs can be stabilized using TECs so that XFP modules can be used for DWDM-type applications.

Abstract: An interference-reducing optoelectronic device determines the value of a current data bit in an optical data stream. A receiver receives the optical data stream, which is converted to a series of samples by a D/A converter. A set of adaptive filters, each filter corresponding to a unique possible value for one or more prior data bits, filters the series of samples utilizing variable tap coefficients to generate filtered output values. The variable tap coefficients are at least partially different than the variable tap coefficients of another adaptive filter. Comparators compare the filtered output values against filter-specific adaptive threshold values to generate tentative values for the current data bit. A delay mechanism delays a determined value for the prior data bits, and a selection mechanism determines the value of the current data bit by selecting the tentative value corresponding to the delayed determined value of the prior data bits.

Abstract: A method of reducing interference in a data stream includes filtering the data stream using a first equalizer to output a first filtered data stream. Also, the data stream is filtered using a second equalizer to create a second filtered data stream. Then, one or more error rates based on the first filtered data stream and the second filtered data stream are determined. Based at least in part on those error rates, a filtered data stream is selected from among the first filtered data stream and the second filtered data stream. A threshold value is determined, and then compared against the selected filtered data stream to generate a data bit.

Abstract: A small form factor transceiver module that incorporates an externally modulated laser (EML). The transceiver module has a transmitter optical subassembly with a header assembly having a base with a platform extending through. The platform has a plurality of conductive traces extending through the platform for making connections on both sides of the base. A thermoelectric cooler (TEC) is used to dissipate heat from a laser within the header assembly. The TEC dissipates heat sufficiently to allow the EML to be used in the header assembly. In this manner, EMLs can be used in relatively small optical devices, including small form factor transceivers that comply with the XFP standard. The XFP modules with EMLs can be used for longer links than XFPs without EMLs. In addition, EMLs can be stabilized using TECs so that XFP modules can be used for DWDM-type applications.

Abstract: An improved monitoring and control system for a laser in a header assembly of a transmitter optical subassembly (“TOSA”) is disclosed. The monitoring and control system, comprising one or more monitor photodiodes (“MPDs”), is positioned together with the laser on a component submount. The submount in turn is mated with a multi-layer platform (“MLP”) that forms part of the header assembly. The MLP hermetically extends through the header assembly to provide a plurality of electrical interconnects for the laser, MPD(s), and other submount components. In one embodiment, a single MPD is located proximate the laser to receive back facet laser light emission. Measurement of the back facet emission enables the MPD to determine laser intensity. In another embodiment, two MPDs are joined together to receive the back facet laser light emission. Comparison of each MPD's measurement enables the laser's wavelength to be determined and adjusted to optimize its performance.

Abstract: A header assembly including a base and a platform extending through the base and substantially perpendicular thereto. The platform includes conductive pathways that connect electrical components on either side of the base, and the conductive pathways cooperate to form a connector at the first end of the platform. A laser is mounted on top of a thermoelectric cooler that is directly joined to the second end of the platform. The laser and thermoelectric cooler are enclosed in a hermetic chamber cooperatively defined by the base, the platform, and a cap that is joined to the base. A photodiode optically coupled with the laser and a thermistor thermally coupled with the laser cooperate with the thermoelectric cooler and a control circuit to facilitate control of the performance of the laser.

Abstract: A single mode high power vertical cavity surface emitting laser (VCSEL) using photonic crystals. A photonic crystal is included in at least one mirror layer of a VCSEL. The reflectivity of the photonic crystal is dependent on the wavelength and incident angle of the photons. The photonic crystal can be formed such that the VCSEL lases at a single mode. Because a single mode is generated, the aperture of the VCSEL can be enlarged to increase the power that is generated by the VCSEL for that mode. The photonic crystal can be used with/without DBR layers. The photonic crystal, in one example, forms an external cavity.

Abstract: A system for data transmission and communication receives a plurality of Gigabit Ethernet data packets from multiple Gigabit Ethernet links. The system bit multiplexes the data packets, on a bit by bit basis, together onto a fiber optic link. At the output of the fiber optic link, the bits are demultiplexed into data packets and transmitted onto multiple Gigabit Ethernet links. The high speed fiber optic link transmits the data at higher speed than is possible over each individual Gigabit Ethernet link.

Abstract: An integrated post-amplifier and laser driver assembly is provided that includes a digital control interface for communication with an external digital IC controller having an I2C bus configured to receive signal parameter programming input from a user. The PA/LD includes one or more DACs which communicate with the digital control interface by way of a glue logic module. A memory is provided in the PA/LD that communicates with the DACs by way of the glue logic module and stores an algorithm for facilitating implementation of changes to signal parameters of one or more signals by way of the DACs. Signal parameter programming instructions are received at the PA/LD from a user by way of the I2C bus, and/or from the internally coded algorithm, and are used by the DACs to facilitate implementation of changes to signal parameters of one or more signals.

Abstract: A single mode high power vertical cavity surface emitting laser (VCSEL) using photonic crystals. A photonic crystal is included in at least one mirror layer of a VCSEL. The reflectivity of the photonic crystal is dependent on the wavelength and incident angle of the photons. The photonic crystal can be formed such that the VCSEL lases at a single mode. Because a single mode is generated, the aperture of the VCSEL can be enlarged to increase the power that is generated by the VCSEL for that mode. The photonic crystal can be used with/without DBR layers. The photonic crystal, in one example, forms an external cavity.

Abstract: The present invention relates generally to optoelectronic devices, and particularly to a submount, pedestal, and bond wire assembly for a transistor outline package. A bottom surface of the submount is connected to a top surface of the pedestal. Each bond wire in a bond wire set is connected to a position on the top surface of the submount, and to a position on the signal line. The signal line is positioned a first distance from the position on the top surface of the submount and a second distance from the pedestal. The submount is sized such that a portion of the bottom and the top surface of the submount extends beyond the top surface of the pedestal such that the first distance is less than the second distance.

Abstract: An optoelectronic assembly includes a circuit board having a set of signal traces, where one or more of the signal traces has a junction point that integrates a pad of a circuit element. Exemplary circuit elements include a resistor, capacitor, and an inductor. The junction point has a first width and a first thickness, and the one or more signal traces have a second width and a second thickness. The dimensions of the junction point and the dimensions of the one or more signal traces are configured such that the first width and the second width are substantially similar, and that the first thickness and the second thickness are substantially similar. In one embodiment, the first width is no greater than 125% of the second width.

Abstract: An improved transistor header assembly incorporating a rectangular platform perpendicularly bisecting the base of the transistor header. The ceramic platform provides the ability to house multiple electrical components and/or devices on either side of the base. The platform has a higher thermal conductivity than the base of a standard header. In addition, the platform increases the electrical input/output density of the header by increasing the number of potential electrical connections between the two sides of the base.

Abstract: An optoelectronic phase locked loop for clock recovery in high-speed optical time division multiplexed systems. The optoelectronic phase locked loop includes a balanced photodetector through which the polarity ambiguity in error signal is resolved and the cancellation of laser noise enabling clock recovery with low timing jitter. The optoelectronic phase locked loop also includes an electroabsorption modulator as a phase detector, a lowpass filter, a variable controlled oscillator, a power divider and an amplifer.

Abstract: A method and apparatus for overcoming modal noise penalties associated with multi-mode fiber optic links operating at high data rates on the order of 10 Gb/s. The method involves restricting the center launch condition of optical signals into the multi-mode fiber while permitting loose tolerances between source and fiber.

Abstract: We have determined that unlike the most multimode silica fiber, multimode polymer fiber often exhibits a delay characteristic that has a broad low dispersion region where propagation delay of spatially restricted optical pulses remains relatively constant. This low dispersion region is centered around the center axis of the fiber core as a function of launch position. By directing a transmitted optical pulse to this region, we have determined that optical pulse dispersion can be significantly reduced without the need for using the prior art technique of using a single mode fiber spliced in series with the multimode fiber to reduce dispersion. A polymer fiber based optical transmission system using this arrangement exhibits relaxed alignment tolerances between the optical source and polymer fiber, while reducing dispersion and increasing bandwidth-length product.