A photonic crystal structure is formed in an n-type layer of a III-nitride light emitting device. In some embodiments, the photonic crystal n-type layer is formed on a tunnel junction. The device includes a first layer of first conductivity type, a first layer of second conductivity type, and an active region separating the first layer of first conductivity type from the first layer of second conductivity type. The tunnel junction includes a second layer of first conductivity type and a second layer of second conductivity type and separates the first layer of first conductivity type from a third layer of first conductivity type. A photonic crystal structure is formed in the third layer of first conductivity type.

Photonic crystal light emitting device

Printed circuit board

A light-emitting device comprising: a first electroluminescent element for emitting light of a first colour when energised; and a second electroluminescent element for emitting light of a second colour when energised, the first electroluminescent element having an active lifetime which is greater than that of the second electroluminescent element; characterised in that the second element is configured to operate at a lower brightness than the first element.

Light emitting devices

A vertical cavity surface emitting laser device includes a first reflective mirror layer, a second reflective mirror layer, and an active layer disposed therebetween, wherein at least one of the first reflective mirror layer and the second reflective mirror layer includes a periodic-refractive-index structure in which the refractive index periodically changes in the in-plane direction and a part of the periodic-refractive-index structure includes a plurality of parts that disorder the periodicity.

Vertical cavity surface emitting laser device

An electronic receiver comprises a nonlinear distortion modeling circuit and a nonlinear distortion compensation circuit. The nonlinear distortion modeling circuit is operable to determine a plurality of sets of nonlinear distortion model parameter values, where each of the sets of nonlinear distortion model parameter values representing nonlinear distortion experienced by signals received by the electronic receiver from a respective one a plurality of communication partners. The nonlinear distortion compensation circuit is operable to use the sets of nonlinear distortion model parameter values for processing of signals from the plurality of communication partners. Each of the sets of nonlinear distortion model parameter values may comprises a plurality of values corresponding to a plurality of signal powers. The sets of nonlinear distortion model parameters may be stored in a lookup table indexed by a signal strength parameter.

Communication methods and systems for nonlinear multi-user environments

Flexible printed circuit boards interconnect to adjacent electronic devices through one or more of high speed data, low speed data, high current, and ground lines and pads. The design of the high speed data pads and traces and adjacent ground pads and traces maintains a desired impedance in the flexible circuit and at the transition from the flexible circuit to a printed circuit board, a ceramic header, or other device to ensure high speed operation. The pads are preferably arranged in a two dimensional geometry such that a connecting area of the flexible circuit is narrower than it would preferably be if the pads were arranged linearly. The two dimensional array also allows the use of the high current thermoelectric cooler pads, which require large surface areas that may otherwise not fit in a conventional linear array.

Flexible circuit for establishing electrical connectivity with optical subassembly

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

Transceiver with programmable signal parameters

This disclosure is concerned with transceiver modules. In one example, a transceiver module includes a receiver optical subassembly, as well as a transmitter optical subassembly having a header assembly and an externally modulated laser (EML). The header assembly includes a base with first and second sides, as well as a platform attached to the base and having an inside portion near the first side of the base and an outside portion near the second side of the base. The platform of the header assembly further includes a conductive pathway extending through part of the platform. The EML is supported by the platform and electrically communicates with the conductive pathway of the platform. The EML can be passively or actively cooled.

Small form factor transceiver with externally modulated laser

This disclosure concerns transceivers that include CDR bypass functionality. In one example, a 1OG XFP transceiver module includes integrated CDR functionality for reducing jitter. The 1OG XFP transceiver module also implements CDR bypass functionality so that the CDR can be bypassed at rate less than about 10Gb/s, such as the Fibre Channel 8.5Gb/s rate for example.

XFP transceiver with 8.5G CDR bypass

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.

Giorgio Giaretta

Papers

Flexible circuit for establishing electrical connectivity with optical subassembly

Transceiver with programmable signal parameters

Small form factor transceiver with externally modulated laser

XFP transceiver with 8.5G CDR bypass

System and method for reducing interference in an optical data stream using multiple, selectable equalizers