Patent application number | Description | Published |
20090022452 | MONOLITHIC TRANSMITTER PHOTONIC INTEGRATED CIRCUIT (TXPIC) WITH A TRANSVERSELY DISPOSED OUTPUT - A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated on the same chip. | 01-22-2009 |
20090022495 | DEPLOYMENT OF ELECTRO-OPTIC AMPLITUDE VARYING ELEMENTS (AVEs) AND ELECTRO-OPTIC MULTI-FUNCTIONAL ELEMENTS (MFEs) IN PHOTONIC INTEGRATED CIRCUITS (PICs) - Electro-optic amplitude varying elements (AVEs) or electro-optic multi-function elements (MFEs) are integrated into signal channels of photonic integrated circuits (PICs) or at the output of such PICs to provide for various optical controlling and monitoring functions. In one case, such PIC signal channels may minimally include a laser source and a modulator (TxPIC) and in another case, may minimally include a photodetector to which channels, in either case, an AVE or an MFE may be added. | 01-22-2009 |
20090175573 | Photonic Integrated Circuits having Chirped Elements - Consistent with the present disclosure, optical devices are provided along different optical paths in a photonic integrated circuit (PIC). The optical components have different optical losses associated therewith so that optical signals propagating in the optical paths have desired power levels, which may be uniform, for example. | 07-09-2009 |
20090245719 | REFLECTION SUPPRESSION IN A PHOTONIC INTEGRATED CIRCUIT - Embodiments of the present invention provide systems, devices and methods in which optical reflections are reduced in a photonic integrated circuit. These embodiments include reflection suppression elements which operate to dissipate optical energy that would otherwise provide a source for optical reflections which may impact the operation of one or more devices within the photonic integrated circuit. In particular, within photonic integrated circuits incorporating semiconductor optical amplifiers, embodiments of the present invention include reflection suppression elements which operate to dissipate optical energy preventing the semiconductor optical amplifiers from operating in a gain-clamped mode. | 10-01-2009 |
20090245795 | HIGH CAPACITY TRANSMITTER IMPLEMENTED ON A PHOTONIC INTEGRATED CIRCUIT - A high capacity optical transmitter implemented on a photonic integrated circuit chip comprises a single light source which supplies a continuous wave having a particular wavelength to a plurality of modulators to form modulated optical information signals. A phase shifter is coupled to at least one of the modulators and is used to shift the phase of the corresponding modulated optical information signal associated with a particular modulator. A polarization beam combiner receives each of the modulated optical information signals from the modulators and the modulated optical information signal from the phase shifter and combines each of these signals to form a polarization multiplexed differential quadrature phase-shift keying signal. The light source, the plurality of modulators, the phase shifter and the polarization beam combiner are all integrated on the chip. | 10-01-2009 |
20100166424 | COOLERLESS PHOTONIC INTEGRATED CIRCUITS (PICs) FOR WDM TRANSMISSION NETWORKS AND PICs OPERABLE WITH A FLOATING SIGNAL CHANNEL GRID CHANGING WITH TEMPERATURE BUT WITH FIXED CHANNEL SPACING IN THE FLOATING GRID - A coolerless photonic integrated circuit (PIC), such as a semiconductor electro-absorption modulator/laser (EML) or a coolerless optical transmitter photonic integrated circuit (TxPIC), may be operated over a wide temperature range at temperatures higher then room temperature without the need for ambient cooling or hermetic packaging. Since there is large scale integration of N optical transmission signal WDM channels on a TxPIC chip, a new DWDM system approach with novel sensing schemes and adaptive algorithms provides intelligent control of the PIC to optimize its performance and to allow optical transmitter and receiver modules in DWDM systems to operate uncooled. Moreover, the wavelength grid of the on-chip channel laser sources may thermally float within a WDM wavelength band where the individual emission wavelengths of the laser sources are not fixed to wavelength peaks along a standardized wavelength grid but rather may move about with changes in ambient temperature. However, control is maintained such that the channel spectral spacing between channels across multiple signal channels, whether such spacing is periodic or aperiodic, between adjacent laser sources in the thermally floating wavelength grid are maintained in a fixed relationship. Means are then provided at an optical receiver to discover and lock onto floating wavelength grid of transmitted WDM signals and thereafter demultiplex the transmitted WDM signals for OE conversion. | 07-01-2010 |
20100247028 | PHOTONIC INTEGRATED CIRCUIT WITH IMPROVED SIGNAL QUALITY AND ELECTROSTATIC DISCHARGE THRESHOLD - Embodiments of the present invention provide for enhanced monitoring of optical signal characteristics of an optical signal propagating in a signal channel of a photonic integrated circuit. The optical signal characteristics can be obtained with minimal signal loss in the optical signal path and reduced RF crosstalk, while the electrostatic discharge threshold for the photonic integrated circuit is increased, due to the inclusion of a second electro-optic element electrically coupled to a first electro-optic element as part of the signal channel. | 09-30-2010 |
20100290790 | TUNABLE PHOTONIC INTEGRATED CIRCUITS - Photonic integrated circuits (PICs) may include transmit and receive PICs that include individually tunable optical elements. In one implementation, a device may include a number of optical elements that form a number of optical channels. Tuners may be used to modify a property associated with the at least one of the optical elements where the modified properties of the optical elements adjust a frequency grid of the optical channels. | 11-18-2010 |
20100320370 | VARIABLE OPTICAL ATTENUATOR - A variable optical attenuator (VOA), which may include a Mach-Zehnder interferometer, is configured such that a substantial part of an input signal is output on a first waveguide, and a relatively small part of the input signal may be output on a second waveguide due to manufacturing process variations and/or other non-idealities. Such residual or extraneous light may interfere with light in the first waveguide, especially if the VOA is integrated on substrate. Accordingly, consistent with an aspect of the present disclosure, a photodiode may be provided to receive and absorb the residual light, thereby minimizing interference or cross-talk with light in the first waveguide. | 12-23-2010 |
20100322628 | COHERENT OPTICAL RECEIVER - A coherent optical receiver circuit is disclosed in which various components of the optical receiver may be provided or integrated, in one example, on a common substrate. Further integration is achieved by incorporating various optical demultiplexer designs that are relatively compact and conserve space on the surface of the substrate. The optical receiver circuit may be used to demultiplex quadrature phase shift keying (QPSK) optical signals. | 12-23-2010 |
20100322629 | POLARIZATION BEAM SPLITTER - Consistent with the present disclosure, a polarization multiplexed optical signal having optical signals with both TE and TM polarizations is supplied to an input of a polarization beam splitter (PBS). The PBS includes a first output that supplies TE polarized optical signals and a second output supplies TM polarized optical signals. A first polarizer is coupled to the second output of the PBS to pass the TM polarized optical signals, while rejecting light having other polarizations, such as the TE polarization. A rotator then rotates the light output from the first polarizer, so that such light has a TE polarization. A second polarizer is coupled to the rotator to filter light having a polarization other than the TE polarization. In addition, a third polarizer is coupled to the first output of the PBS in order to filter or block any TM light, for example, that may be output from the PBS with the TE polarized signal. Accordingly, the optical signals in the polarization multiplexed optical signal are effectively filtered, and some are rotated so that each has the same, e.g., TE polarization. Moreover, each optical signal is substantially free from light having extraneous polarizations and may be supplied to an optical hybrid circuit. Data carried by such optical signals may thus be reliably recovered. | 12-23-2010 |
20100322631 | Optical receiver integrated on a substrate - A coherent optical receiver circuit is disclosed in which various components of the optical receiver may be provided or integrated, in one example, on a common substrate. Further integration is achieved by incorporating various optical demultiplexer designs that are relatively compact and conserve space on the surface of the substrate. The optical receiver circuit may be used to demultiplex quadrature phase shift keying (QPSK) optical signals. | 12-23-2010 |
20110001204 | TRANSIMPEDANCE AMPLIFIER HAVING A SHARED INPUT - Consistent the present disclosure, a receive circuit is provided that includes a balanced detector portion and a transimpedance amplifier (TIA). The anode of one photodiode is connected to the cathode of the other by a bonding pad, which supplies the sum of the currents generated in each photodiode to an input of the TIA. Thus, the TIA may, for example, have a single input, as opposed to multiple inputs, thereby reducing the number of connections so that the photodiodes and the TIA may be integrated onto a smaller die. In addition, since there are few connections, fewer TIAs are required and differential stages are unnecessary. Power consumption is thus reduced, and, since the photodiode current is fed through one input to the TIA, fewer feedback resistors are required, thereby reducing thermal noise. In addition, since the anode of one photodiode is connected to the cathode of the other, the dark current generated in each flows in opposite directions, and is therefore effectively cancelled out. Since one input is provided, impedance matching with other inputs is unnecessary, nor is additional DC biasing circuitry needed. As described in greater detail below, an example of the present disclosure includes a bonding pad, which connects the two photodiodes and provides the input current to the TIA. | 01-06-2011 |
20110147874 | PHOTODIODE ISOLATION IN A PHOTONIC INTEGRATED CIRCUIT - Consistent with the present disclosure, a current blocking layer is provided between output waveguides carrying light to be sensed by the photodiodes in a balanced photodetector, and the photodiodes themselves. Preferably, the photodiodes are provided above the waveguides and sense light through evanescently coupling with the waveguides. In addition, the current blocking layer may include alternating p and n-type conductivity layers, such that, between adjacent ones of such layers, a reverse biased pn-junction is formed. The pn-junctions, therefore, limit the amount of current flowing from one photodiode of the balanced detector to the other, thereby improving performance. | 06-23-2011 |
20110150384 | OPTICAL INTEGRATED CIRCUIT - Consistent with the present disclosure, a non-adiabatic polarization rotator is provided that can rotate the polarization of an incoming over a relatively short length. Light is supplied to the polarization rotator via a polarizer, which insures that the optical input to the polarization polarization rotator has a desired polarization. Preferably, the polarization rotator has a structure that is readily implemented with semiconductor materials and can be fabricated with known processing techniques. In addition, the polarization rotator and polarizer may include similar materials and/or layers, such that both may be readily integrated on a common substrate, such as an indium phosphide (InP) substrate. | 06-23-2011 |
20110150471 | TRANSMITTER PHOTONIC INTEGRATED CIRCUIT - The present invention provides a system, apparatus and method to provide for amplification at various points along one or more optical paths of a photonic integrated circuit. According to various embodiments of the invention, the photonic integrated circuit includes a plurality of optical devices having associated characteristics which may have lead to optical signal degradation. One or more optical amplifiers provided along one or more optical paths of the photonic integrated circuit compensate for such signal degradation, resulting in a highly configurable photonic integrated circuit. The various optical devices of the photonic integrated circuit may be provided on a single substrate. | 06-23-2011 |
20110243556 | TRANSCEIVER PHTONIC INTEGRATED CIRCUIT - The present invention provides for a transceiver comprising a transmitter portion and a receiver portion. The transmitter portion includes a laser, the laser providing an optical signal having one of a plurality of wavelengths. The optical signal from the laser is modulated to create a first wavelength-division multiplexed signal at an output of the transceiver. The optical signal from the laser is also used by a demultiplexer to demultiplexer a second wavelength-division multiplexed signal at an input of the transceiver. The use of the optical signal from the laser in both modulation and demodulation of wavelength-division multiplexed signals results in a transceiver having fewer discrete components resulting in a compact design and reduced costs. | 10-06-2011 |
20110249936 | TRANSMITTER PHOTONIC INTEGRATED CIRCUIT (TxPIC) CHIP - A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated on the same chip. | 10-13-2011 |
20110293280 | Control of an Interferometric Optical Polarization Beam Splitter - The present invention provides a system, apparatus and method to control an optical polarization beam splitter. A portion of an optical output of the polarization beam splitter is converted into a corresponding electrical signal. The electrical signal is then provided to the polarization beam splitter as a control signal via a feedback loop. The polarization beam splitter controls a characteristic of the optical output of the polarization beam splitter in response to the received control signal. The characteristic, for example, may be controlled through thermo-optically or electro-optically. The control system may be used over a period of time to maintain the characteristic at a desired value, for example as the components of the polarization beam splitter, or other elements used in the control of the polarization beam splitter, age. | 12-01-2011 |
20120057874 | WAVELENGTH DIVISION MULTIPLEXED PASSIVE OPTICAL NETWORK - Consistent with the present disclosure, an optical communication system, such as a passive optical network (PON), is provided that includes an optical line terminal (OLT) and a plurality of optical network units (ONUs). The OLT includes a plurality of photonic integrated circuits that have both optical transmitters and receivers provided therein. Accordingly, the OLT may have fewer components and a simpler, more reliable and cost-effective design than a conventional OLT including discrete components. In addition, various ONU configurations are provided that also have a simple design and fewer components. Thus, ONUs consistent with the present disclosure may also have reduced costs. | 03-08-2012 |
20120057875 | WAVELENGTH DIVISION MULTIPLEXED PASSIVE OPTICAL NETWORK - Consistent with the present disclosure, an optical communication system, such as a passive optical network (PON), is provided that includes an optical line terminal (OLT) and a plurality of optical network units (ONUs). The OLT includes a plurality of photonic integrated circuits that have both optical transmitters and receivers provided therein. Accordingly, the OLT may have fewer components and a simpler, more reliable and cost-effective design than a conventional OLT including discrete components. In addition, various ONU configurations are provided that also have a simple design and fewer components. Thus, ONUs consistent with the present disclosure may also have reduced costs. | 03-08-2012 |
20130011098 | WIDE PASSBAND AWG - Consistent with the present disclosure, an AWG is provided that has grating waveguide groupings that extend between a first free space region and a second free space region. The difference in length (ΔL) between successive grating waveguides differs for each grouping of grating waveguides, such that, for example, the ΔL associated with a given grating waveguide grouping is not an integer multiple of any of the other grating waveguide groupings. The grating waveguide groupings direct images having relatively small wavelength differences to a given output waveguide, and each grating waveguide grouping has an associated passband, which is similar to that of the conventional AWG. Unlike the conventional AWG, however, multiple grating waveguide groupings are included in the same AWG, such that the spectra associated with the grating waveguide groupings combine to provide a transmission characteristic having a passband that is greater than any individual passband. Accordingly, even if the optical signal wavelengths vary or are offset from the center wavelength of the passband, such wavelengths may still be transmitted with less loss. | 01-10-2013 |
20130170787 | OPTICAL COMMUNICATION SYSTEM HAVING TUNABLE SOURCES - Consistent with one example of the disclosed implementations, a photonic integrated circuit (PIC) may be provided that includes s group of lasers and an arrayed waveguide grating (AWG) disposed on a substrate. Each laser in the group may supply an optical signal, such that each optical signal has a different wavelength. Each laser may be tunable to at least two designated wavelengths, which are separated from one another by a free spectral range (FSR) of the AWG. As a result, the optical signals provided from each laser may be combined by the AWG, regardless of which designated wavelength the optical signals have. Accordingly, a PIC may be provided that has a relatively simple construction but can supply optical signals having tunable wavelengths. | 07-04-2013 |
20130170833 | OPTICAL COMMUNICATION SYSTEM HAVING TUNABLE SOURCES - Pairs of distributed feedback (DFB) lasers are provided on a substrate. An arrayed waveguide grating (AWG) is also provided on the substrate having input waveguides, each of which being connected to a corresponding pair of DFB lasers. The wavelengths of optical signals supplied from each pair of DFB lasers may be spectrally spaced from one another by a free spectral range (FSR) of the AWG. By selecting either a first or second DFB laser in a pair and temperature tuning to adjust the wavelength, each pair of DFB lasers can supply optical signals at one of four wavelengths, pairs of which are spectrally spaced from one another by the FSR of the AWG. A widely tunable transmitter may thus be obtained. | 07-04-2013 |
20130279910 | Banded Semiconductor Optical Amplifier - A semiconductor optical amplifier module may include a beam splitter to split an optical signal into two polarization optical signals including a first polarization optical signal with a Transverse Magnetic (TM) polarization provided along a first path of two paths, and a second polarization optical signal with a Transverse Electric (TE) polarization provided along a second path of the two paths; a first rotator to rotate the TM polarization of the first polarization optical signal to TE polarization; a first semiconductor optical amplifier to amplify the rotated first polarization optical signal to output a first resultant optical signal; a second semiconductor optical amplifier to amplify the second polarization optical signal; and a second rotator to rotate the polarization of the amplified second polarization optical signal to output a second resultant optical signal; and a beam combiner to combine the first resultant optical signal and the second resultant optical signal. | 10-24-2013 |
20130279911 | RAMAN PUMP CIRCUIT - A Raman pump may include a dual output laser configured to output two optical signals; a delay interferometer configured to delay a first of the two optical signals to decorrelate the two optical signals from each other; and a combiner configured to combine the delayed first of the two optical signals and a second of the two optical signals to provide a Raman amplification signal. | 10-24-2013 |
20140001347 | ROTATOR EXTERNAL TO PHOTONIC INTEGRATED CIRCUIT | 01-02-2014 |
20140003759 | SHARED PROPAGATION REGION FOR AN OPTICAL MULTIPLEXER OR AN OPTICAL DEMULTIPLEXER | 01-02-2014 |
20140003763 | COHERENT DETECTION FOR AN INTEGRATED CIRCUIT HAVING A MULTIPLEXER OR A DEMULTIPLEXER WITH A SHARED PROPAGATION REGION | 01-02-2014 |
20140003764 | POLARIZATION MATERIAL ON AN OPTICAL MULTIPLEXER OR AN OPTICAL DEMULTIPLEXER | 01-02-2014 |
20140133793 | POLARIZATION BEAM SPLITTER - An optical system may include: a polarization beam splitter having: a first end having an input configured to receive multiple optical signals; a second end having a first output and a second output, where the first output may provide first components, having a first polarization of the multiple optical signals, and the second output may provide second components, having a second polarization, of the multiple optical signals; and a first waveguide having a first width and a second waveguide having a second width, where the first waveguide and the second waveguide may each have a length corresponding to a difference between the first width and the second width, where the first waveguide and the second waveguide may be configured to induce a phase shift of the plurality of optical signals based on the first width, the second width, and the length of the first waveguide and the second waveguide. | 05-15-2014 |
20140133868 | INTENSITY-BASED MODULATOR - An optical modulator includes a splitter, phase modulators, amplitude modulators, intensity modulators, and a combiner. The splitter is configured to receive light, and split the light into portions of the light. Each of the phase modulators is configured to receive a corresponding one of the portions of the light, and modulate a phase of the portion of the light to provide a phase-modulated signal. Each of the amplitude modulators is configured to receive a corresponding one of the phase-modulated signals, and modulate an amplitude of the phase-modulated signal to provide an amplitude-modulated signal. Each of the intensity modulators is configured to receive a corresponding one of the amplitude-modulated signals, and modulate an intensity of the amplitude-modulated signals to provide an intensity-modulated signal. The combiner is configured to receive the intensity-modulated signals, combine the intensity-modulated signals into a combined signal, and output the combined signal. | 05-15-2014 |