185 results about "Avalanche photodiode" patented technology

The invention provides a single-photon detector gating signal generation system and generation method. The system comprises a bias voltage source; the gating circuit is provided with a first sine branch and a second sine branch, the first sine branch is configured to output a first sine voltage signal, and the second sine branch is configured to output a second sine voltage signal; the frequency of the first sinusoidal voltage signal is greater than that of the second sinusoidal voltage signal; the second sinusoidal voltage signal, the first sinusoidal voltage signal and the bias voltage signal are matched to generate a gating signal acting on the avalanche photodiode; based on the period of the first sinusoidal voltage signal, the gating signal has an amplitude greater than a preset value in a continuous first number of periods, and the gating signal does not have an amplitude greater than the preset value in a subsequent continuous second number of periods. The generated gating signal can accelerate the carrier removal process from the physical mechanism level, the post-pulse probability is suppressed, the required dead time is effectively shortened, and the data rate of the detector is further improved.

The invention provides an FSO multi-sensor fusion method based on unscented Kalman filtering and an RBF neural network, and the method comprises the steps: carrying out the unscented Kalman filtering time updating, and carrying out the measurement of a noise covariance adjustment mechanism and an event triggering mechanism based on light intensity self-adaption; the unscented Kalman filter measures and adjusts confidence weights of the infrared camera and the four-quadrant detector according to the channel state provided by the avalanche photodiode, and processes data output by the infrared camera and the four-quadrant detector according to the confidence weights; then, the posterior state estimation of the unscented Kalman filter at the current moment is output, and a position component is extracted and transmitted. Normalized light intensity reflecting channel quality is used as a key state to carry out synchronous estimation, an RBF neural network is used to carry out dynamic modeling and compensation on nonlinear errors of a four-quadrant detector, and a self-adaptive unscented Kalman filtering framework with a line learning capability is constructed. And finally, a virtual sensor output with high update rate, high precision and high sensitivity is generated.

The present disclosure aims to provide a photoelectric conversion device capable of suppressing an increase in power consumption of a SPAD pixel. For example, a photoelectric conversion device may include an avalanche photodiode including an anode and a cathode in each pixel of a pixel array. The device may include a recharger configured to recharge the anode or the cathode once per unit exposure time, a gating circuit configured to generate a pulse signal based on an output of the avalanche photodiode at a plurality of different timings within the unit exposure time, and a counter configured to count the pulse signal from the gating circuit.

A controller for an avalanche photodiode sensor, including circuitry configured to: control a latch circuit to store one or more least significant bits of a counter value of a counter circuit at the end of a first frame, wherein the counter circuit is configured to count exposure time intervals of a frame in which an avalanche photodiode pixel has generated a light detection event; enable readout of the one or more least significant bits from the latch circuit in a second frame following the first frame; and enable readout of one or more most significant bits of the counter value from the counter circuit in the second frame.

An optical sensor includes an integrated circuit including an array of time-to-digital converters and a first array of interconnects connected to the array of time-to-digital converters. A plurality of single photon avalanche photodiode circuits includes a second interconnect. Each of the plurality of single photon avalanche photodiode circuits corresponds to a single pixel. The plurality of single photon avalanche photodiode circuits are individually arranged on the integrated circuit with the second interconnect of the plurality of single photon avalanche photodiode circuits connected to a corresponding one of the first interconnects of the integrated circuit.

In a signal processing circuit, an input terminal is configured to receive an analog signal output from an avalanche photodiode operating in Geiger mode. A comparison circuit outputs a signal based on a component exceeding a threshold among components a signal input to the comparison circuit. The adjustment circuit includes an AC coupling unit, a level shifter unit, and a reference value adjustment unit. The AC coupling unit establishes AC coupling between the input terminal and the comparison circuit. The level shifter unit adjusts the voltage of the signal input to the comparison circuit to a value lower than a reverse bias voltage applied to the avalanche photodiode. The reference value adjustment unit adjusts the reference value of the signal input to the comparison circuit.

The application relates to an avalanche diode single-photon detector and a preparation method thereof, in particular to a quantum dot-vertical linear avalanche diode single-photon detector and a preparation method thereof, and solves the problems of low detection efficiency of the existing single-photon detector and high preparation difficulty, high cost and limited effect of the existing method. + The detector comprises a detector N + substrate, a back electrode grown on the lower surface thereof, a plurality of quantum dot-vertical linear units arranged at intervals on the upper surface thereof, a passivation layer and a front electrode; the quantum dot-vertical linear unit comprises a semiconductor vertical linear structure, a porous nanomaterial layer and a quantum dot material layer; the semiconductor vertical linear structure is grown on the upper surface of the detector N + substrate; the porous nanomaterial layer covers the semiconductor vertical linear structure; the quantum dot material layer covers the porous nanomaterial layer; the passivation layer is filled between the quantum dot-vertical linear units; and the front electrode is grown on the part of the quantum dot-vertical linear unit extending out of the passivation layer.

A single Geiger avalanche photodiode pixel interconnected with a readout circuit is decomposed to form M * M parallel pixel structures, the M * M parallel pixel structures are connected to a single pixel input stage of the readout circuit, and the time complementation relation between pixel avalanche events is utilized to enlarge the pixel avalanche events. The detection probability of the array single-photon detector pixel is improved, the photon detection dynamic range is expanded, the upper limit of the pixel photon saturation counting rate of the array single-photon detector can be remarkably improved, and the method is applied to the fields of high-dynamic-range laser three-dimensional imaging, space laser communication and the like.

The invention provides an avalanche photodiode with asymmetric optical resonance and a photosensitive array, and the avalanche photodiode comprises an electrode layer which is internally provided with a first windowing region; the top reflecting mirror is arranged in the first windowing area, the transmittance of the incident side of the top reflecting mirror to the light with the target wavelength is higher than a preset transmittance threshold value, and the reflectivity of the emergent side of the top reflecting mirror to the light with the target wavelength is higher than a preset reflectivity threshold value; the substrate is arranged on the emergent side of the top reflecting mirror; the buffer layer is arranged on one side, deviating from the top reflecting mirror, of the substrate; the active region is arranged on the side, away from the top reflector, of the buffer layer; and a bottom high reflective metal film. The top reflector and the bottom high-reflectivity metal film form an asymmetric optical resonant structure, and the purposes of filtering and absorption enhancement are achieved. And the bottom high-reflection metal film is low in process difficulty and suitable for preparation of large-array devices.

The application provides an avalanche photodiode focal plane array pixel gain simulation method and device, the method comprises the following steps: respectively under dark field conditions and light field conditions, a varying bias voltage is applied to an avalanche photodiode focal plane array, and a dark current response curve and a photocurrent response curve of an anode current of a pixel unit in the focal plane array are obtained respectively; under different bias voltages, a signal difference between the dark current response curve and the photocurrent response curve is extracted, and the pixel gain of the pixel unit is determined according to the signal difference. The pixel gain simulation method provided by the application can accurately obtain the pixel gain and is suitable for a silicon-based APD focal plane detector array with different pixel unit structures. In addition, the method can reveal the influence of internal electric field distribution changes caused by factors such as bias voltage on the array gain, thereby providing a theoretical basis and technical path for device optimization design in actual application scenarios.

Method for detecting high-energy radiation in a harsh environment, wherein the method comprises: Exposure of a scintillator single crystal to high-energy radiation at a temperature of more than approximately 175°C; and Detecting the high-energy radiation with an avalanche photodiode coupled to the scintillator, wherein the scintillator single crystal has a praseodymium-doped composition; characterized by the fact that the scintillator single crystal (La x Y 1-x ) 2Si2O7: Pr is, where (0, 2

An imaging device includes: a photoelectric conversion element including an avalanche photodiode; a generation unit configured to generate an image based on a signal acquired by the photoelectric conversion element; a first correction unit configured to correct the image based on first characteristic information on crosstalk between pixels of the photoelectric conversion element; and a second correction unit configured to perform pixel interpolation of the image based on second characteristic information for determining a crosstalk region to neighboring pixels of a specific pixel and the image.

The embodiment of the invention provides an avalanche photodiode, a photoelectric detection chip and optical communication equipment, relates to the technical field of photoelectric conversion devices, and aims to solve the problems of relatively large noise and dark current in a waveguide type avalanche photodiode. The avalanche photodiode comprises a first semiconductor layer and a second semiconductor layer, wherein the first semiconductor layer comprises a waveguide part and a device part which are arranged in a first direction; in a second direction perpendicular to the first direction, the device part comprises a first ohmic contact region, a first charge region, a first multiplication region, a second charge region and a second ohmic contact region which are arranged in sequence; the first charge region, the second charge region and the first ohmic contact region are all P-type doped regions, the second ohmic contact region is an N-type doped region, and the first multiplication region is an intrinsic region. The second semiconductor layer is arranged on one side of the first semiconductor layer and is in contact with the first charge region; the light-emitting diode is used for absorbing incident light to generate photon-generated carriers. The avalanche photodiode can be applied to optical communication.

A distance measurement method which measures a distance by irradiating an object 3 with pulsed light from a pulsed fiber laser device 10, receiving reflected pulsed light of the irradiation pulsed light being reflected by the object, and converting a time interval from projection of the irradiation pulsed light to reception of the reflected pulsed light into a distance, includes detecting the irradiation pulsed light and the reflected pulsed light by an avalanche photodiode 21, calculating a peak value of the irradiation pulsed light based on the detection of the irradiation pulsed light, and controlling the peak value of the irradiation pulsed light to be generated so as to be constant based on the calculated peak value.

This light detection element is provided with: a first semiconductor layer having a first main surface, which is a light incident surface, and a second main surface on the opposite side from the first main surface; a layer structure formed on the first main surface; a metal wiring line located inside the layer structure; and a plurality of quenching elements. The first semiconductor layer has: a plurality of first semiconductor regions of a first conductivity type; a plurality of second semiconductor regions of a second conductivity type that constitute a plurality of avalanche photodiodes together with the plurality of first semiconductor regions; and a plurality of third semiconductor regions of the first conductivity type having an impurity concentration higher than that of the first semiconductor regions. The thickness of the metal wiring is greater than the distance from a first surface of the metal wiring on the opposite side to the first main surface to a surface of the layer structure on the opposite side to the first main surface, and is greater than the distance from a second surface of the metal wiring on the first main surface side to the surface of the layer structure on the first main surface side.

The invention relates to the technical field of photoelectric detection, and discloses a wide-spectrum photoelectric detector based on a crystalline silicon-organic composite heterojunction, which comprises a crystalline silicon avalanche photodiode (APD) layer and an organic semiconductor active layer. Through an energy band matching design, the organic layer covers the surface of the micro-nano structure of the crystalline silicon APD to form a synergistic photoelectric response interface. The structure utilizes the high gain characteristic of the crystalline silicon APD and the broadband spectrum absorption advantage of the organic material to realize the broadband spectrum detection from visible light to near infrared light. In addition, the light capture efficiency is remarkably enhanced through the micro-nano structure design, and the exciton dissociation efficiency is improved through interface electric field regulation and control. The invention solves the problems of narrow spectral range and low sensitivity of the traditional photoelectric detector, and is suitable for medical health monitoring and high-speed optical communication systems.

A photoelectric convertor is provided. The convertor includes first and second pixels each including an avalanche photodiode and a counter, and a processor. The first and second pixels repeat a detection operation including exposure intervals in which the counter counts a number of times that an avalanche breakdown occurred in the photodiode and holding intervals in which a count value counted in the exposure interval is held in the counter. After a predetermined time has elapsed from the start of a first exposure interval of the first pixel, a second exposure interval of the second pixel is started. The processor outputs a difference value between a first count value counted in the first exposure interval and held in the counter in a first holding interval that continues from the first exposure interval and a second count value counted in the second exposure interval.

A photoelectric conversion device includes an avalanche photodiode, an output holding circuit configured to hold a light reception signal based on an output of the avalanche photodiode, a first logic circuit to which the light reception signal held in the output holding circuit and a first reference signal indicating a first weight amount are input, and a first accumulating circuit configured to hold a first count value obtained by accumulating an output of the first logic circuit. The first accumulating circuit resets the first count value for each first period. The first period is divided into a plurality of second periods. The first weight amount changes for each second period. The output holding circuit resets the light reception signal for each second period.

The invention belongs to the technical field of blocking capacitor matching of double transimpedance amplifiers, and discloses a blocking capacitor-based double-path transimpedance amplifier, which comprises a direct current leakage circuit module for receiving light current input from a reverse bias APD (avalanche photodiode) and converting the light current input into a current pulse signal for output; the two blocking capacitors are respectively coupled to the output end of the direct-current bleeder circuit module, receive current pulse signals output by the direct-current bleeder circuit module and respectively transmit the signals to the two negative feedback trans-impedance amplifiers which are connected in parallel; the two negative feedback type transimpedance amplifiers are connected in parallel and respectively receive the current pulse signals from the corresponding blocking capacitors and convert the current pulse signals into voltage pulse signals; and the signal fusion amplifier receives the voltage pulse signal, carries out fusion processing and then outputs a final voltage pulse signal. By means of the two blocking capacitors, the effect of resisting APD process changes is achieved, and meanwhile the core performance of the whole circuit can be adjusted by adjusting the specific value of the two capacitors.

The application discloses a preparation method of a high-gain photoelectric detector and relates to the technical field of photoelectric detectors.The application comprises the following steps: S1, structure design: according to the application scene requirement and working environment of the detector, an avalanche photodiode is prepared by selecting a corresponding photoelectric material; S2, wafer preparation: a semiconductor wafer is cleaned by using ultrasonic cleaning agent and chemical solution; S3, material processing: a doping operation is performed, ions containing phosphorus and boron elements are injected into semiconductor material by using an ion accelerator; S4, gain optimization: a circuit is optimized by using Cascode technology, and the circuits of two transistors are connected; and S5, packaging integration: a prepared chip is packaged into a shell; by optimizing the circuit of the semiconductor by using the Cascode technology, the bias voltage of the circuit, the configuration of the gain circuit and external signal processing are adjusted, the gain of the photoelectric detector can be improved, the influence on the output impedance is reduced, and therefore the high-frequency performance and the linearity of the overall circuit are improved.

A light detection device (1) includes: a first avalanche photodiode (11A) that amplifies carriers generated by incident photons, the first avalanche photodiode being disposed in a first region (A1) of a first substrate (101) and having a first anode region (104A) to be supplied with a first anode voltage; and a second avalanche photodiode (11B) that amplifies carriers generated by incident photons, the second avalanche photodiode being disposed in a second region (A2) of the first substrate (101), which is different from the first region (A1), and having a second anode region (104B) to be supplied with a second anode voltage lower than the first anode voltage.

This light detection element is provided with: a first semiconductor layer having a first main surface, which is a light incident surface, and a second main surface on the opposite side from the first main surface; an insulating layer formed on the first main surface; a second semiconductor layer formed on the first main surface via the insulating layer; and a quenching element facing the second main surface side. The first semiconductor layer has: a first semiconductor region of a first conductivity type; a second semiconductor region of a second conductivity type that constitutes an avalanche photodiode together with the first semiconductor region; and a third semiconductor region of the first conductivity type, which is located closer to the first main surface than the first semiconductor region, and which has an impurity concentration higher than that of the first semiconductor region. The quenching element is electrically connected to the second semiconductor region. A textured structure having an uneven shape is formed on the surface of the second semiconductor layer.

The application belongs to the technical field of random number generation, and particularly relates to a random signal generation device based on a saturable absorber semiconductor laser. The device comprises a random self-pulsation entropy source, a photodetector and a pulse amplitude quantization module. The random self-pulsation entropy source adopts a saturable absorber semiconductor laser (preferably a DFB-SA structure), generates optical pulses with random amplitudes and stable repetition periods by injecting a driving current in a gain region and applying a reverse bias voltage in an absorption region; the photodetector adopts a PIN photodiode or an avalanche photodiode to convert the optical pulses into corresponding electrical pulses; and the pulse amplitude quantization module comprises a differential comparator and a peak detection circuit, which quantizes the peak value of the electrical pulses in each pulse period by using a fixed threshold or an adaptive threshold to generate a random bit sequence. The application realizes high-speed and high-stability random signal generation without an external electric clock, an ADC and digital post-processing, and has a simple device structure, low power consumption and high integration.

A photoelectric conversion apparatus includes a semiconductor layer including an avalanche photodiode. The avalanche photodiode includes a first semiconductor region provided at a first depth position, a second semiconductor region located closer to the second surface than the first semiconductor region, a third semiconductor region that is located closer to the second surface than the second semiconductor region, is in contact with a contact plug to which a first voltage is applied, and is provided to a second depth position, a region that is in contact with a contact plug to which a second voltage is applied and provided to a third depth position, and a fourth semiconductor region provided between the region and the third semiconductor region. The photoelectric conversion apparatus includes a dielectric member including at least a portion located on a portion overlapping the fourth semiconductor region and extending over the third depth position.

A method for adjusting the operating point of an avalanche photodiode is provided, in which the supply voltage of the avalanche photodiode is changed gradually and the total noise and the amplifier noise of an amplifier connected to the avalanche photodiode are determined, wherein the supply voltage is kept constant after reaching a certain ratio between the total noise and the amplifier noise.

The invention provides a processing apparatus, a processing method, a non-transitory computer-readable storage medium, and a computer program product. The processing device generates and corrects an image on the basis of a count value output by a photoelectric conversion element having an avalanche photodiode, converting light from a subject into an electrical signal, counting the electrical signal, and outputting the count value, the processing apparatus generates a first image based on a count value and performs a correction process for correcting the first image, in which the correction process includes: a first correction process for a first pixel including pixels in a surrounding area of a first type of defective pixel miscounted due to a first cause; and a second correction process different from the first correction process for a second pixel, the second pixel including pixels in a peripheral region of a second-type defective pixel that has been miscounted due to a second cause different from the first cause.

This application discloses a signal receiving system, a signal processing method, and a detection chip. The signal receiving system includes a receiving array, N accumulation units, N buffer units, N event determination units, and a summarizing unit. The receiving array includes N receiving units. Each accumulation unit increments the photon count by one each time an avalanche breakdown occurs within a preset time period, obtaining a frame grayscale value for the corresponding pixel. The buffer units, upon receiving the current frame grayscale value of a corresponding pixel, store the current frame grayscale value and output the previous frame grayscale value. The event determination units determine whether an event has occurred for each pixel based on the difference between the current frame photon count value and the previous frame photon count value. The summarizing unit summarizes the difference, coordinates, and timestamp information corresponding to the pixels that have experienced events into event data. Through this method, an event camera can be implemented using a single-photon avalanche photodiode array.

The invention relates to the technical field of OTDR (Optical Time Domain Reflectometer), in particular to an optical transceiving integrated device and method for inhibiting an overlarge front-end blind area, and the device comprises a laser which is used for generating test light; the polarization controller is used for adjusting the test light into linearly polarized light only containing an S component; the slide is arranged on the emergent light path of the polarization controller, and the included angle between the normal and the incidence direction of the adjusted test light is a Brewster angle; the detection end of the device is arranged in the direction of a reflection light path of the adjusted test light by the slide and is used for placing an optical fiber to be tested, so that the device emits the test light reflected by the slide to the optical fiber to be tested; enabling the device to receive backward Rayleigh scattering light returned by the optical fiber to be detected; and the avalanche photodiode is arranged on a transmission light path of the slide to the backward Rayleigh scattering light and is used for receiving the backward Rayleigh scattering light penetrating through the slide. Therefore, the advantages of preventing APD supersaturation during short-distance testing and improving the signal-to-noise ratio during long-distance testing are achieved at the same time.

The disclosure provides an avalanche photodetector excess noise factor measurement system and a measurement method. The avalanche photodetector excess noise factor measurement system comprises a carrier device, a light source, a spectrum analyzer, a biasing device, a source voltage meter and a high-frequency probe; the carrier device is used for placing a device to be measured, the device to be measured comprising an avalanche photodetector chip; the light source is used for outputting constant light to the avalanche photodetector chip for noise testing; and the avalanche photodetector chip is connected with the biasing device, the biasing device is connected with the source voltage meter based on a direct current channel, and the biasing device is connected with the spectrum analyzer based on an alternating current channel through the high-frequency probe to form a noise testing link.

An image capturing apparatus comprises a photoelectric conversion element having a plurality of pixels, wherein each pixel comprises a sensor unit comprising an avalanche photodiode configured to generate pulses in response to photons incident thereon, a counter configured to count the number of the pulses, a memory configured to store count values of the counter, and a switch configured to switch the avalanche photodiode between a standby state in which avalanche multiplication is possible and a recharge state, a signal generation unit configured to supply a clock signal to the switch, a light emitting unit configured to perform pulse light emission for illuminating a subject in synchronization with the clock signal, and a control unit configured to perform a plurality of exposure operations by the counter according to timing of the pulse light emission and a predetermined image-capturing distance range for capturing images of a subject existing in the predetermined image-capturing distance range, and configured to shift relative timing of the clock signal and the pulse light emission by a predetermined phase for each predetermined exposure operation.