237 results about "Avalanche photodiode" patented technology

A visualization system for dynamically visualizing an eye includes a laser module operable for outputting a primary laser beam along a beam axis, a beam splitter positioned in the beam axis and configured to direct a first beam portion along the beam axis and a second beam portion along a detection axis that is orthogonal to the beam axis. A microelectromechanical system (MEMS) scanner is arranged on the beam axis and configured, in response to the first beam portion, to output a scanning laser along a visualization path. An avalanche photodiode (APD) detector receives the second beam portion. A 4F correlator optical system has a spatial filter arranged along the visualization path. An optional optical flat may be disposed between the eye and the 4F correlator optical system to achieve stereo parallax.

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.

A semiconductor element including an array in which a plurality of avalanche photodiodes is arranged includes a plurality of first electrodes configured to receive supply of a first voltage to be used by the plurality of avalanche photodiodes from outside, and at least one second electrode configured to receive supply of a second voltage from outside different from the first voltage. The plurality of first electrodes and the at least one second electrode are disposed outside the array. The at least one second electrode is disposed between one and another one of the plurality of first electrodes.

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.

To provide a photoelectric conversion device that has an avalanche photodiode and can suppress image quality deterioration, in a photoelectric conversion device, a photoelectric conversion element including an avalanche photodiode for photoelectrically converting an optical image, an image generation unit configured to generate a first image based on a signal acquired by the photoelectric conversion element, an acquisition unit configured to acquire first characteristic information of the photoelectric conversion element, and a correction processing unit configured to perform first correction processing on the first image by using the first characteristic information are provided, and in the correction processing unit, weighting of the first correction processing is made different according to a magnitude of a pixel signal in the first image.

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.

The present invention discloses a visible light communication device based on a power line carrier circuit and a communication method thereof. The device includes: an Ethernet interface circuit, a power line carrier circuit, a switching switch, a signal attenuation circuit, a light source driving circuit, a light source, an avalanche photodiode, a photoelectric conversion circuit, a linear amplifier circuit, and a power detection circuit. The switching switch can switch the signal transmission mode from visible light communication to power line communication when the optical communication quality is poor, thereby improving the stability of the communication system. The power line carrier circuit modulates the signal in various ways, including OFDM, QPSK, BPSK, and ROBO. Compared with traditional visible light communication systems using OOK modulation, the communication rate and stability are significantly improved. The power detection circuit, the signal attenuation circuit, and the light source driving circuit cooperate to effectively control the power of the transmitted signal, enabling the signal to be transmitted without distortion. In addition, the power line can be replaced with a wire, twisted pair, etc., further improving the anti-interference capability and mobility.

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 discloses a GaN-based bidirectional dual-waveband avalanche photodetector based on a back-to-back p-i-n structure, which comprises two back-to-back dual photodiode structures which share a p-type layer and grow on a substrate, namely a p-i-n structure taking GaN as an intrinsic layer and an SACM structure taking Al < 0.45 > Ga < 0.55 > N as an intrinsic layer. Compared with a traditional ultraviolet avalanche photodiode, the bidirectional dual-band avalanche photodiode can achieve avalanche multiplication under the forward bias voltage and the reverse bias voltage, and different working modes can be achieved by adjusting the external bias voltage. In a forward bias mode, the device is cut off at 365 nm, and in a reverse bias mode, the cut-off wavelength of the device is 281 nm, so that dual-band ultraviolet signal detection is realized, and the dual-band detection method is beneficial to accurate identification of signals and further popularization and application.

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.

1. The name of the design product: avalanche photodiode test fixture. 2. The use of the design product: for testing avalanche photodiodes. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view.

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.

To provide an avalanche photodiode capable of lessening concentration of an electric field and also reducing parasitic capacitance.SOLUTION: There is provided an avalanche photodiode that comprises a first mesa with a light reception region, a first electrode provided at the first mesa, a second mesa connected to the first mesa, and a pad provided at the second mesa and electrically connected to the first electrode, and a connection part where the first mesa and second mesa are connected has a plane shape which is curved inward convexly.SELECTED DRAWING: Figure 1B

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.

1. The name of the design product: single photon detector shell. 2. The use of the design product: the design product is used in weak light detection field, and is suitable for space target surface avalanche photodiode single photon detector. 3. The design points of the design product: in shape. 4. The picture or photo that can best show the design points: perspective view.

The invention relates to measuring the distance of an object using a light time-of-flight method. There is provided a photoelectric sensor for measuring a distance of an object in a detection area using a light time-of-flight method, the sensor comprising: a light emitter for emitting a light signal into the detection area; a light receiver having a first plurality of avalanche photodiodes in Geiger mode for detecting received light from the detection region; a second plurality of light time-of-flight measurement units for determining a single light time-of-flight between the emission of the light signal and the triggering of the probe event in the avalanche photodiode; and a control and evaluation unit which is designed to collect the individual light time-of-flight in the histogram, to locate the useful light signal in the histogram on the basis of a threshold value, and to determine a distance value to the object as a function of the useful light signal. An extraneous light level is first estimated from the histogram, and then a threshold is determined based on the extraneous light level such that the threshold lies above the expected number of exponentially decaying noise and extraneous light events with a safety margin.

The invention discloses a nanowire avalanche photodiode with the barrier height of an electron barrier controlled by a grid, which comprises a back electrode, an ohmic contact layer and a first part arranged on the ohmic contact layer, the back electrode and the ohmic contact layer are sequentially arranged from bottom to top, the first part is sleeved with a second part, and the first part and the second part are combined to form a nanowire structure; the first part is a lattice matching layer, the second part is a light absorption layer, and a first superlattice material layer is arranged between the first part and the second part; an electron barrier layer is arranged outside the second part, and a second superlattice material layer is sleeved outside the electron barrier layer; the electron blocking layer is blocked between the second part and the second superlattice material layer; the electron blocking layer is led out through a first top electrode, the second superlattice material layer is led out through a second top electrode, and a first insulating layer is arranged between the first top electrode and the second superlattice material layer; the barrier height of the electron blocking layer is regulated and controlled through the grid voltage, and collection of electron current is reduced.

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.

This light detection device comprises: an avalanche photodiode in which a first fixed voltage is applied to one of an anode region and a cathode region, and a carrier generated by an incident photon is multiplied; a protection circuit which is electrically connected in series to the other of the anode region and the cathode region, and which has a resistance element (R) for protecting an internal circuit against an overcurrent; and a first conductor (1141) which is electrically connected in parallel to the resistance element (R).