Abstract: Low-noise optical differential receivers are described. Such differential receivers may include a differential amplifier having first and second inputs and first and second outputs, and four photodetectors. A first and a second of such photodetectors are coupled to the first input of the differential amplifier, and a third and a fourth of such photodetectors are coupled to the second input of the differential amplifier. The anode of the first photodetector and the cathode of the second photodetector are coupled to the first input of the differential amplifier. The cathode of the third photodetector and the anode of the fourth photodetector are coupled to the second input of the differential amplifier. The optical receiver may involve two stages of signal subtraction, which may significantly increase noise immunity.

Abstract: An analog front-end module of an ultra-wideband optical receiver including a transimpedance amplifying unit and a distributed amplifier unit is provided. The transimpedance amplifying unit is configured to convert an externally-inputted current signal into a voltage signal, amplify the voltage signal, and then output a voltage-amplified signal. The distributed amplifier unit includes an input transmission network, an input matching load, an output transmission network, an output matching load, and a plurality of gain units. The input transmission network is configured to receive the voltage-amplified signal and distribute the voltage-amplified signal to each gain unit for further amplification. The input matching load is configured to absorb the voltage-amplified signal reflected to the transimpedance amplifying unit. The output transmission network is configured to superimpose amplified signals outputted from the gain units and output in combination.

Abstract: A device comprising a low-power oscillator having an oscillator output, the oscillator when triggered produces X number of oscillator pulses in series at a high repetition rate from the oscillator output, where X is an integer. The device comprises a plurality of X series coupled amplifiers having a common optical path. The plurality of X amplifiers amplify a power parameter of the X number of oscillator pulses. A first amplifier of the plurality of X amplifiers is coupled to the oscillator output. The plurality of amplifiers are triggered in sequence in accordance with the high repetition rate of the oscillator so that an output from a last amplifier of the plurality of X amplifiers is a burst of X amplified pumping oscillator (APO) pulses with high-peak power and high-average power over the burst of APO pulses. A system and a method are also provided.

Abstract: An electronic circuit includes an isolation amplifier, having a first input terminal receiving an AC-signal and including a linear opto-isolator. The opto-isolator has a first output terminal that provides a unipolar signal having an AC-component proportional to the input signal. The circuit includes a transimpedance receiver with first and second operational amplifiers. The first amplifier has a second output terminal and first and second differential input terminals, with the first differential input terminal receiving and amplifying the unipolar output signal from the first output terminal providing an output signal from the circuit at the second output terminal.

Abstract: A data communication system is disclosed including a cable medium and modulator adapted to carry data and power between a high speed data source and a high speed data sink. Relatively high speed data (e.g. the TMDS data of an HDMI interface) may be carried on optical waveguides in the cable medium. Relatively low-speed data (e.g., DDC data and clock, and CEC of an HDMI interface) may be carried on a separate set of optical waveguides or wire mediums. The optical waveguides allow for substantially less signal distortion of the high-speed data, thereby allowing the cable medium to achieve much higher lengths without significantly affecting the high-speed signaling.

Abstract: The present disclosure relates to an electrical connector for providing signal isolation between various components of a physiological monitoring system. In an embodiment, the electrical connector is placed between a sensor and associated monitoring system and includes a physical barrier and inductive components.

Abstract: A data communication system is disclosed including a cable medium and modulator adapted to carry data and power between a high speed data source and a high speed data sink. Relatively high speed data (e.g. the TMDS data of an HDMI interface) may be carried on optical waveguides in the cable medium. Relatively low-speed data (e.g., DDC data and clock, and CEC of an HDMI interface) may be carried on a separate set of optical waveguides or wire mediums. The optical waveguides allow for substantially less signal distortion of the high-speed data, thereby allowing the cable medium to achieve much higher lengths without significantly affecting the high-speed signaling.

Abstract: CIC Hearing device (50, 1000, 1100) comprising electronics configured to receive an electrical signal as an input signal and generate an output signal provided to a receiver, the electronics including a variable gain amplifier with input buffering circuitry including a compound transistor, the electronics being configured to bias the compound transistor such that a quiescent current associated with the output signal is limited or controlled.

Abstract: A data communication system is disclosed including a cable medium and modulator adapted to carry data and power between a high speed data source and a high speed data sink. Relatively high speed data (e.g. the TMDS data of an HDMI interface) may be carried on optical waveguides in the cable medium. Relatively low-speed data (e.g., DDC data and clock, and CEC of an HDMI interface) may be carried on a separate set of optical waveguides or wire mediums. The optical waveguides allow for substantially less signal distortion of the high-speed data, thereby allowing the cable medium to achieve much higher lengths without significantly affecting the high-speed signaling.

Abstract: A detector circuit can include an integrator having an amplifier, a first feedback capacitor connected between an input and output of the amplifier, one or more additional feedback capacitors connected by at least one switch between the input and output of the amplifier, and a shunt capacitor connected to the output of the amplifier. The shunt capacitor can be selected to have a capacitance value greater than that of a minimum but less than that of a maximum feedback capacitance. The detector circuit can further include a sampling circuit having a sampling capacitor connected to the output of the integrator amplifier through at least one switch, wherein the sampling capacitor is separate from the shunt capacitor. A computed tomography imaging apparatus can include the detector circuit.

Abstract: A photodetector receiver circuit for an optical communication system includes an optical photodetector which receives optical signals and converts them into an electrical current. In one illustrative embodiment, a dynamic impedance module which switches the receiver circuit between a high impedance state and a low impedance state and a buffer stage which receives the electrical current and converts the electrical current into a voltage signal compatible with a digital circuit. A method for receiving an optical signal includes, receiving the optical signal and converting it into an electrical pulse train, switching a dynamic impedance module between a high impedance state and a low impedance state, transforming the electrical pulse train into an output voltage signal using a buffer stage, and receiving the output voltage signal by a digital circuit.

Abstract: An opto-isolated amplifier and method are disclosed. The amplifier includes an input node configured to receive an input to be amplified. A pair of opto-isolators are coupled between an input node and an output node. The opto-isolators are configured to create gain between the input node and the output node. An amplification stage is coupled to the opto-isolators. The amplification stage includes an input coupled to the output node and an output configured to generate an amplified output. The opto-isolator outputs may be configured to generate a difference current. The input of the amplification stage may have a high impedance compared to an impedance at the output node, the difference current being directed at the high input impedance input of the amplification stage to generate a gained voltage.

Abstract: An amplification device that amplifies a signal, the amplification device includes an amplification unit that amplifies the signal using supplied power, a variable power supply unit that changes the power supplied to the amplification unit in accordance with an envelope of the signal, a radiation unit that radiates light onto the amplification unit, and a control unit that controls the light to be emitted from the radiation unit in accordance with slope of the envelope of the signal.

Abstract: A burst optical signal receiving device is provided, which includes an optical receiving component and a limiting amplifying circuit unit. The optical receiving component further includes a photodetector, a trans-impedance amplifier, a first direct current (DC) cancellation forbidding circuit, and a DC bias circuit, and the limiting amplifying circuit unit further includes a group of alternating current (AC) coupling capacitors, a limiting amplifier, and a second DC cancellation forbidding circuit. Through the technical solution, an input burst optical signal within a certain dynamic range can be recovered into a valid burst electric signal in shorter time. The technical solution can be applied in a burst optical signal receiver in a 10-Gigabit Ethernet passive optical network (10GEPON).

Abstract: The invention relates to an image sensor, in particular to a CMOS sensor, having a plurality of light sensitive pixels arranged in rows and columns for the generation of output signals proportional to the exposure, wherein column lines are associated with the columns to supply the output signals to at least one column amplifier for amplification, wherein the at least one column amplifier cooperates with the column lines such that the amplification of the respective output signal depends on the capacitance of the respective column line.

Abstract: An integrated circuit transimpedance amplifier arrangement constituted of: a plurality of internal matched resistors; a current multiplier arranged to output a signal whose value is a function of an input current signal, an external resistor and a first set of the plurality of internal matched resistors; and an output transimpedance amplifier coupled to the output of the current multiplier, the output transimpedance amplifier exhibiting a gain whose value is a function of a second set of the plurality of internal matched resistors, wherein the output of the output transimpedance amplifier is a function of the input current signal, the external resistor, the first set of the plurality of internal matched resistors and the second set of the plurality of internal matched resistors, wherein the variations with temperature of the first set of the plurality of internal matched resistors and the second set of the plurality of internal matched resistors cancel.

Abstract: The present invention provides a system, apparatus and method to improve the signal-to-noise ratio performance in receivers configured to receive differential data signals. According to various embodiments of the invention, a received differential signal is processed to consider both forward-looking and backward-looking error components to improve SNR performance, and ultimately the reach of the optical line system. Additional processing is provided to further enhance noise tolerance related to chromatic dispersion.

Abstract: A signal amplifier connected to a photodetector that converts a received optical signal to a current signal includes: a preamplifier converting the current signal to voltage and supplying the resultant voltage signal; a main amplifier amplifying the voltage signal supplied from the preamplifier and in which at least the input stage is made up from a differential circuit; two or more follower circuits provided between the preamplifier and the main amplifier and supplied with the voltage signal; resistors of equal resistance provided for each follower circuit on the paths between the output of the preamplifier and each input of the main amplifier; and a capacitor having one end connected to one of the resistors and the other end connected to ground. A low-pass filter for detecting the average potential of the voltage signal is configured by the capacitor and the resistor that is connected to the capacitor.

Abstract: Techniques are provided for implementing a burst mode optical receiver capable of maintaining a stable gain profile in response to a burst signal. The optical receiver has a photodiode in balanced circuit configuration with a separate RF amplifier stage connected to each terminal of the photodiode. The two RF amplifier stages are coupled to biasing voltage sources that are inverted in comparison to the terminal connections and that, in some examples, each contain a field effect transistor (FET) that having a gate that is controlled in response to a sensed voltage. The burst mode optical receiver may be used in numerous applications, including optical line terminations (OLTs) in passive optical networks (PONs).

Abstract: A scanning projector includes a mirror that scans in two dimensions, at least one of which is sinusoidal. A position sensor provides a position signal that represents an angular displacement of the mirror. The position signal is amplified by an amplifier with time variant characteristics. A beam position determination component compensates for the time variant characteristics of the amplifier.

Abstract: A system is disclosed for an improved ROSA that has increased sensitivity for permitting greater numbers of ONTs to be connected to an optical network per defined transmission line distances. The ROSA configuration includes a digital optical module with improved performance characteristics. This digital optical module has replaced a conventional photodiode with a PIN detector that is coupled with the TIA. The resulting digital optical module containing this PIN/TIA configuration when incorporated in a ROSA provides a single ROSA solution that will meet or exceed the ITU/IEEE FTTx standards for short and long distances under substantially all operating conditions.

Abstract: Systems and methods for transferring incoming single-ended burst signals of which at least one characteristic varies widely from burst to burst onto a pair of differential lines. The systems comprise an input for receiving an incoming burst signal, a signal adaptation block for adapting said widely varying characteristic and a single-ended-to-differential converter. In a first aspect a reset signal for resetting a settings determination block, which controls the signal adaptation block, is sent backwards over the differential lines, preferably using a common-mode signal. In a second aspect, a status freezing mechanism is employed for freezing the settings of the settings determination block after the end of the preamble of an incoming burst.

Abstract: An optical receiver includes a light receiving element for converting an optical signal to an electrical signal having a first bandwidth and an amplifier for amplifying the electrical signal. The amplifier has a first gain response that yields a second bandwidth that is less than the first bandwidth. The optical receiver also includes an equalizing circuit operationally coupled to the amplifier. The equalizing circuit has a second gain response that compensates for the first gain response of the amplifier so that a substantially constant net gain is imparted by the amplifier and the equalizing circuit to the electrical signal over the first bandwidth.

Abstract: A current mirror circuit and an optical receiver circuit implementing with the current mirror circuit are disclosed. The current mirror circuit provides two MOSFETs and two differential amplifiers. The MOSFETs are operated under the same bias condition even the power supply voltage decreases due to the virtual short-circuit characteristic between two inputs of the differential amplifier. One of the differential amplifiers provides a variable gain and output impedance characteristic to stabilize the feedback loop formed by this differential amplifier and one of the MOSFETs.

Abstract: A digital audio signal amplifier and a digital audio signal amplifying method provide safety and power efficiency by integrating a switching mode power supply and a digital audio amplifier into an apparatus. The digital audio amplifier includes a pulse modulation unit generate a pulse modulated audio signal by pulse-modulating an input audio signal, a switching unit to switch a DC voltage based on the pulse modulated audio signal, an insulation transformer to transform the output of the switching unit and to output the result of the transforming, and a low-pass filter to obtain an audio signal corresponding to the input audio signal by low-pass filtering the output of the insulation transformer, and to output the output audio signal. By integrating a switching mode power supply and a digital audio amplifier into an apparatus, the digital audio amplifier satisfies the insulation requirement and at the same time increases power efficiency.

Abstract: Configurable amplifiers for optical receivers and transceivers are disclosed. In one aspect, a configurable amplifier may be coupled with an output of a current-to-voltage converter to receive a voltage. The configurable amplifier may be capable of being configured to use either a substantially linear amplifier portion or a substantially non-linear amplifier portion to amplify the voltage.

Abstract: In an IR communication network, a method is described to optimize channel performance in the presence of strong and varying IR interference. The method controls of the channel gain based on quantitative measurement of the channel noise.

Abstract: A preamplifier circuit for processing a signal provided by a radiation detector includes a transimpedance amplifier coupled to receive a current signal from a detector and generate a voltage signal at its output. A second amplification stage has an input coupled to an output of the transimpedance amplifier for providing an amplified voltage signal. Detector electronics include a preamplifier circuit having a first and second transimpedance amplifier coupled to receive a current signal from a first and second location on a detector, respectively, and generate a first and second voltage signal at respective outputs. A second amplification stage has an input coupled to an output of the transimpedance amplifiers for amplifying the first and said second voltage signals to provide first and second amplified voltage signals.

Abstract: The present invention discloses a cryogenic receiving amplifier using a gallium nitride high electron mobility transistor (GaN HEMT) as an amplifying device in a cryogenic temperature environment. The cryogenic receiving amplifier includes an input matching circuit which makes an impedance matching between a gate of the amplifying device and an outside of an input terminal, a gate biasing circuit which applies a DC voltage to the gate of the amplifying device, an output matching circuit which makes an impedance matching between a drain of the amplifying device and an outside of an output terminal, and a drain biasing circuit which applies a DC voltage to the drain of the amplifying device. The cooled temperature is preferably set to 150 K or below, and the GaN HEMT may be illuminated with light of a blue LED.

Abstract: A learning remote “learns” both a digital code carried by an infrared operational signal as well as a timing characteristic (for example, time period) of a carrier used to modulate the operational signal. When the photodiode of the learning remote is close to the transmitter of the remote to be learned from, a low frequency saturation current is superimposed on the intelligence signal. Rather than using a fixed reference voltage to detect when the carrier component of the intelligence signal transitions, an adaptive reference voltage (VAR) is used. A comparator compares a photocurrent voltage to VAR. Because VAR is maintained between the envelope of positive peaks and the envelope of negative peaks of the photocurrent voltage despite changes in the low frequency current, the comparator detects each transition of the carrier component. A microcontroller timer determines the time between transitions output by the comparator and thereby determines the timing characteristic.

Abstract: Testing is performed on an amplifier wafer housing a transimpedance amplifier prior to packaging the transimpedance amplifier with an external photodetector, wherein the transimpedance amplifier includes a small, auxiliary, integrated silicon photodetector provided at the input of the transimpedance, in parallel with external photodetector attachment points. Totest the transimpedance amplifier, the transimpedance amplifier is stimulated by optically exciting the small auxiliary photodetector, wherein the small auxiliary photodetector is excited using short wavelength light, whereby advantages such as higher efficiency may be obtained. The testing method includes placing the amplifier wafer in a testing system, probing the power and ground connections on the amplifier wafer, illuminating the small auxiliary photodetector on the amplifier wafer, and detecting the output of the transimpedance amplifier housed on the amplifier wafer.

Abstract: In an optical telecommunication system in which an intensity of an arriving optical signal is different for each packet, detected is an optical intensity for each packet with little error. For this purpose, contrived is to detect an average optical intensity across header parts for each packet by focusing on the fact that the header part comprising the preamble and delimiter of a packet is in a bit pattern which includes approximately the same numbers of “0” and “1”.

Abstract: A transfer circuit that transmits a signal includes an electrical signal sending section that sends a sending signal, a current to light converting section that converts the sending signal to an optical signal, an optical signal transmitting section that transmits the optical signal, a photo-electric converting circuit that converts the optical signal to an electrical signal, and an electrical signal receiving section that detects a data value of the electrical signal. The photo-electric converting circuit includes a level measuring section that compares the intensity of the electrical signal and a predetermined reference level to detect a data value of the electrical signal, and a measurement controlling section that controls the reference level. The electrical signal receiving section includes a receiving circuit that detects a data value of the electrical signal, and a timing controlling section that controls latch timing at which the receiving circuit detects the data value.

Abstract: A bandwidth adjustable transimpedance amplifier. The bandwidth adjustable transimpedance amplifier includes a feedback path with a selectable resistance. The bandwidth adjustable transimpedance amplifier is preferably implemented with a photodiode in a five pin package for an optical transceiver system, with a single pin providing a monitor out function and a rate select input.

Abstract: An LED driver circuit includes a power controller, a voltage regulator, a detecting resistor, a light emitting device, and a voltage detecting circuit. The voltage detecting circuit has a first input end connected to a higher potential end of the detecting resistor, and a second input end thereof is connected to a lower potential end of the detecting resistor. The output end of the voltage detecting circuit is connected to a feedback end of the power controller so as to output a detected voltage signal to the power controller for adjusting the output voltage and supplying a stable and proper value of current to the light emitting device. The voltage detecting circuit is a differential amplifier capable of detecting the voltage difference between the detecting resistor and amplifying it as a feedback to the power controller. Therefore, the output current from the power controller is precisely controlled.

Abstract: An optoelectronic device has a bright detector and a dark detector and reduces noise in the output of the bright detector using the output of the dark detector.

Abstract: In a wavelength-division-multiplexing optical transmission system in which optical-node apparatuses that perform relay transmission of wavelength-division-multiplexed light are located at specified nodes in a main optical transmission path, an optical amplifier switches level control to constant-gain control when there is a notification of a change in the number of multiplexed wavelengths, and then after a specified amount of time restarts level control so that the level becomes a target level that corresponds to the actual number of wavelengths.

Abstract: A laser driver for high speed interconnections may convert a digital signal to a current train of a bias mode to represent logical zero and of a modulation mode to represent logical one. An optical signal thus produced may include an optical offset. An optical receiver may include a photo-detector to receive the optical signal and generate a current signal, which includes a corresponding current offset. A first amplifier stage converts the current signal to a voltage signal and a second amplifier stage generates a digital output from the voltage signal. One or more low-pass filters may be used to filter the digital output and generate a filtered offset signal for a differential amplifier to generate an offset cancellation signal. The offset cancellation signal may be provided to offset cancellation circuitry to remove the current offset from the current signal generated by the photo-detector.

Abstract: An optical receiver includes a first light receiving element to convert an optical signal to an electric signal and to output the electric signal from one end. A light receiving element row is connected to the other end of the first light receiving element to supply electric power to the first light receiving element. The light receiving element row includes a plurality of second light receiving elements connected in series.

Abstract: A trans-impedance amplifier with gain control for a fiber optic rotation rate sensor. A variable gain amplifier having gain control based on keeping the amplifier output above a certain level. The gain control approach allows the amplifier bandwidth to remain constant. A gain control circuit includes a control device connected to ground and the amplifier feedback network. The input to the gain control circuit may be the amplifier output that has been filtered, or the input could be from an external circuit or microcontroller.

Abstract: A microstructure is formed on a conductor. The microstructure is equipped with a dielectric base material, in which a great number of fine holes having substantially the same shape in plan view are formed. The fine holes are open at the surface of the dielectric base material, and are substantially uniformly provided therein. A plurality of micro metal members are fixed to the dielectric base material. The micro metal members include filling portions that fill one or more of the fine holes, and protruding portions that protrude from the surface of the dielectric base material and are of diameters greater than the fine holes, capable of inducing local plasmon. The plurality of micro metal members include those that have different numbers of filling portions.

Abstract: In an optical communication-use receiving circuit of the present invention, the pulse width of the received pulse which is a binary signal corresponding to the signal optical pulse is specified by using an integration circuit and a trigger generating circuit. If the pulse width of the received pulse is not shorter than a predetermined value, a signal having a fixed pulse width is outputted as an output signal from a one-shot pulse generating circuit, so that a pulse having a constant pulse width corresponding to the specified communication speed is outputted. Accordingly, if the pulse width deriving from the signal optical pulse is larger than a certain value, the communication is deemed as a low-speed communication, and a pulse having a constant pulse width corresponding to the communication speed is outputted. As a result, it is possible to realize a small-size receiving circuit and a small-size electronic device which require no external switching-over terminal.

Abstract: A transimpedance amplifier (TIA) with integrated filtering. A capacitance is integrated into the TIA and connected to the power supply and to an internal ground of the TIA. Noise on the power supply of the transimpedance amplifier is filtered by the capacitor such that the power supply noise is reduced. The integrated capacitor also reduces noise ground. The integrated capacitor also reduces the effects of common mode noise that may be received from another circuit.

Abstract: An optical receiver circuit is constructed to be immune to interference from external interference signals. The optical receiver circuit includes a differential amplifier having an optical reception device connected to one input of the differential amplifier. The optical receiver circuit also includes an electrical element for simulating the electrical behavior of the reception device in the illumination-free state. The electrical element is connected to the other input of the differential amplifier.

Abstract: The inventors propose herein a switch fabric architecture that allows broadcasting and fast channel access in the ns-range. In various embodiments of the present invention, 10 Gb/s receiver modules are based on a novel heterodyne receiver and detection technique, which is tolerant to moderate wavelength drifts of a local oscillator. A gain clipped electrical amplifier is used in the novel receiver as a rectifier for bandpass signal recovery.

Abstract: The low noise light receiver comprises a light sensor for generating a sensor signal, the sensor signal comprising a wanted signal resulting from a light source and an interfering signal resulting from interfering light; an optical filter apparatus for reducing the interfering light; an electric filter apparatus connected to the light sensor for filtering out the interfering signal and for generating a correction signal that substantially compensates for the interfering signal; and a processing apparatus connected to the light sensor and the electric filter apparatus for processing the wanted signal in order to generate an output signal (Vout).

Abstract: Disclosed is a transresistance amplifier for a charged particle detector, comprising a variable input resistance, which may be a phototransistor (IC3), a voltage amplification stage (IC1) and control means (IC3), operable to vary the variable input resistance. The variable input resistance includes a first light-dependent resistance and the control means includes a first variable intensity light source that is optically coupled to the first light-dependent resistance. Also disclosed is a charged particle detector that includes such a transresistance amplifier and an electron microscope that includes such a charged particle detector.

Abstract: An optical receiver in an optical communication system, and more particularly, to a method and an apparatus for optimizing a decision level of a signal output from an optical receiver to obtain a minimum bit error rate (BER) by measuring output characteristics of the optical receiver and adjusting a reference voltage of the optical receiver based on a measurement result. The provided method includes measuring the strength of an electric signal at a modulated frequency out of the frequency elements of the output electric signal in the optical receiver, generating a reference voltage based on the strength data of the electric signal, inputting the reference voltage to the optical receiver and re-measuring the strength of the electric signal output from the optical receiver to determine whether the strength of the signal is minimum, and maintaining the reference voltage when the strength of the signal is minimum and adjusting the reference voltage in other cases.

Abstract: An optical receiver. The optical receiver includes a photodiode, a differential transimpedance amplifier, a transistor, and a current source. When the photodiode receives an optical signal, a current signal transmitted from a cathode of the photodiode to an anode thereof is generated. Two input terminals of the differential transimpedance amplifier couple the current signal, and the differential transimpedance amplifier converts the current signal to a voltage signal. In addition, voltage variation of the cathode is coupled to the anode through a voltage follower composed by the transistor and the current source. As a result, voltage of the cathode and that of the anode vary in phase, effectively decreasing a value of the photodiode parasitic capacitance and improving operating bandwidth.

Abstract: An Improved Signal Receiver Having Wide Band Amplification Capability is disclosed. Also disclosed is a receiver that is able to receive and reliably amplify infrared and/or other wireless signals having frequency bandwidths in excess of 40 MHz. The receiver of the present invention reduces the signal-to-noise ratio of the received signal to ?th of the prior systems. The preferred receiver eliminates both the shunting resistor and the feedback resistor on the input end by amplifing the signal in current form. Furthermore, the receiver includes transconductance amplification means for amplifying the current signal without the need for Cascode stages. Finally, the receiver includes staged amplification to amplify the current signal in stages prior to converting the signal into a voltage output.