513 results about "Photon detection" patented technology

The invention discloses a high-speed multi-photon detection system and method. The system comprises a detector and a signal processing circuit, wherein the detector is composed of a window plated with a photoelectric cathode, a micro-channel plate stack and an anode; a plurality of incident photons are converted into a plurality of photoelectrons by the photoelectric cathode, and the photoelectrons are converted into electron cloud by the micro-channel plate stack; the incident electron cloud is divided into multiple paths by three layers of staggered metal strip electrodes of the anode, and charge collection is carried out to obtain charge short pulses of each layer of electrode; the signal processing circuit converts the charge short pulses transmitted by the three layers of electrodes into digital pulse signals, obtains the centroid coordinates of the electron cloud from the digital pulse signals as the abscissa value, the ordinate value and the verification value of the incident photon position, combines the abscissa value, the ordinate value and the verification value based on the screening condition to obtain the target two-dimensional coordinates, and finally obtains the target two-dimensional coordinates. And transmitting to a terminal for imaging display. According to the invention, a plurality of synchronous photons can be detected, the overall counting rate of the detector is greatly improved, and the detection efficiency is improved.

Embodiments of a present disclosure relate to communication systems and more particularly to a system and a method for a point-to-point decoy differential phase shift (DPS) Quantum Key Distribution (QKD). The system includes a source QKD device and a destination QKD device. The source QKD device generates and transmits one or more quantum states comprising a series of N coherent pulses with one or more phases to the destination QKD device. The destination QKD device receives, and records time information and corresponding detector units associated with each photon detection event in the received quantum states. The source and destination QKD devices use decoy states to detect and prevent attacks, such as Photon-Number-Splitting (PNS) attacks. The system allows for the secure generation of a secret key between the source and destination QKD devices.

The invention discloses a double-comb non-cooperative target ranging system based on single photon detection, which is characterized in that an optical pulse output by a first optical frequency comb is divided into two paths of light through a first beam splitter, the first path of light is combined with one of two paths of light divided by a second optical frequency comb through a second beam splitter, and the combined light is transmitted to a first nonlinear frequency up-conversion module; a sum frequency light pulse in the wave band of 780 nm is generated and detected by a base avalanche diode photoelectric detector, and then a time-dependent single photon counter is triggered to start counting; the second path of light is output to a beam expanding collimator through the circulator and irradiates a target to be measured through spatial propagation, the beam expanding collimator collects diffuse reflection light and returns the diffuse reflection light to a third port of the circulator along the original path, and the diffuse reflection light and the other path of light split by the second optical frequency comb through the second beam splitter are combined and transmitted to a second nonlinear frequency up-conversion module; the up-conversion light after sum frequency conversion passes through the optical filter group and then is recorded by a stop end of the single photon counting module, multi-cycle accumulative statistics is carried out by the time correlation single photon counter, and finally a photon counting waveform is reconstructed and the flight time difference of the to-be-measured target is calculated by the computer.

The invention relates to a closed circulation 226Ra solution target system for producing 225Ac. The closed circulation 226Ra solution target system comprises a solution type 226Ra target, an isotope target bin, a valve, a 226Ra solution circulation structure, a radium actinide separation structure, a radium lead separation structure, a photon detection system I, a photon detection system II, a heat exchange system, a pressure reduction radon evaporator and a radon treatment system, and the solution type 226Ra target comprises a solution circulation pipeline and a radium-containing solution. The radium-containing solution is contained in the closed solution circulating pipeline; the solution circulating pipeline comprises a main loop pipeline and two branch pipelines; the photon detection system I, the 226Ra solution circulation structure, the pressure reduction radon evaporator, the heat exchange system, the valve and the photon detection system II are sequentially arranged on the main loop pipeline; and the radium actinide separation structure and the radium lead separation structure are respectively arranged on the two branch pipelines. The system can improve the preparation efficiency and yield of 225Ac.

The invention provides a light intensity measurement method and device based on single-photon detection and electronic equipment, and relates to the technical field of single-photon detection and laser radar imaging, and the method comprises the steps: collecting the arrival time information of photons in a plurality of single-photon detection events for each detection position; extracting a time sequence characteristic quantity related to the light intensity estimation based on the arrival time information; constructing a model input parameter for estimating the target light intensity based on the time sequence characteristic quantity; inputting the model input parameters into a light intensity estimation model, and predicting a light intensity estimation value of the target light intensity; and generating a corresponding light intensity distribution image according to the light intensity estimation value. According to the method, high-precision light intensity estimation can be realized only by a few photons, the requirements on the repeated detection times and the signal-to-background ratio are greatly reduced, and the imaging robustness is enhanced.

The invention relates to a quantum computer, which comprises a sample (21) with paramagnetic centres, preferably in the form of NV centres (22), and a pumping radiation source (1). The pumping radiation source (1) irradiates, by means of an optical system, the paramagnetic centres and / or NV centres (22) with pumping radiation (54) of a pumping radiation wavelength (λpmp) over a first optical partial path. The optical system detects the fluorescent radiation (33) of the paramagnetic centres (22) and guides the fluorescent radiation (33) to a photodetector (50) and / or a single-photon detector (50) over a second optical partial path. The first optical partial path differs from the second optical partial path at least in some portions. The photodetector (50) and / or the single-photon detector (50) convert the fluorescent signal of the fluorescent radiation (33) of the paramagnetic centres (22) into at least one measurement signal and / or at least one measurement value. The quantum computer uses this at least one measurement signal and / or this at least one measurement value to carry out a quantum operation. The device is characterised in that the quantum computer has an optical spatial filter in the second optical partial path.

An example photon detection circuit, a SPAD sensing device, and a direct time-of-flight detection system comprising a SPAD sensing device configured to operate in a high illumination environments, are provided. The example photon detection circuit includes SPAD circuitry configured to generate a photon detection signal based on a SPAD bias voltage and the number of photons encountering the SPAD. The photon detection circuitry further includes output bias circuitry configured to generate a dynamic output bias signal, wherein the dynamic output bias signal is updated based on the number of photons encountering the SPAD. The example photon detection circuitry further includes output signal circuitry configured to generate a photon detection output signal in an instance in which the photon detection signal exceeds an output signal circuitry threshold, wherein the output signal circuitry threshold is based on the dynamic output bias signal.

An apparatus and method are provided to correct for time-walk errors during photon detections (e.g., detecting gamma rays). A time-walk correction is determined using measurements of energy (or charge) that apply different time windows, enabling corrections accounting for variations in the ratio between fast and slow components in the detected pulse. For example, one time window can be used to integrate the leading end of the pulse, thereby predominantly measuring the fast component, while a second window is used to integrate a trailing end of the pulse to predominantly measure the slow component. Alternatively or additionally, low-pass and high-pass filters may select the slow and fast components, respectively. The time-walk correction is a function of multiple measurements representing different components (e.g., fast and slow) of the pulse shape.

The invention discloses an imaging method and an imaging device, and relates to the field of imaging, and the imaging method comprises the steps: enabling pulse laser to irradiate a to-be-measured target which rotates according to a time sequence, and obtaining the respective reflection laser of the to-be-measured target at a plurality of rotation angles; sequentially performing single-photon detection on the reflected laser to determine the flight time of a target photon in the reflected laser; taking the distribution result of the flight time obtained at the plurality of rotation angles as observation data; iteratively executing the following operations until the value of the optimization objective function meets a preset condition to obtain a three-dimensional image of the to-be-measured target: determining the probability that the observation data can be measured when the three-dimensional image of the to-be-measured target is the predicted three-dimensional image according to the rotation matrix of the to-be-measured target, the predicted three-dimensional image of the to-be-measured target and the observation data; determining a value of an optimization objective function according to the probability and the predicted three-dimensional image; and changing the predicted three-dimensional image according to the value of the optimized objective function.

The invention discloses a scanning device of a single-photon laser radar three-dimensional imaging system for a dynamic target, and belongs to the field of laser radar optical design. The system comprises a laser emission subsystem, a light path subsystem, a detection subsystem, a data acquisition and processing subsystem, a control subsystem and a two-dimensional rotary table, the laser emission subsystem generates laser beams, and the light path subsystem emits the laser beams to a detection target area and receives scattering echo signals; scattered echo signals are subjected to sum-frequency conversion and angle calculation to obtain point cloud information, the detection subsystem collects the point cloud information, and the data processing system reconstructs a dynamic three-dimensional image of a to-be-detected target according to two-dimensional scanning distribution information and the point cloud information. The device is used for carrying out three-dimensional laser imaging on a dynamic cooperative target under single-photon detection, the frequency up-conversion technology and the rapid scanning assembly are combined, the space scanning efficiency is improved, and the problem of long-distance dynamic target detection in existing single-photon detection is solved.

The invention discloses a high-resolution fast compressed sensing single photon array imaging system and method, and relates to the technical field of weak light imaging and computational imaging. The system comprises an imaging light source, an optical attenuator, a light beam expander, a to-be-detected target, a signal generator, a spatial light modulator, a single photon detection array, a counting storage module and a data processing module. Wherein the imaging light source is used for emitting a light beam to illuminate a target scene to be imaged; the optical attenuator, the light beam expander, the target to be measured and the spatial light modulator are sequentially arranged on a transmission light path of a light beam; the signal generator is respectively connected with the spatial light modulator and the single photon detection array; and the single photon detection array, the counting storage module and the data processing module are connected in sequence. According to the invention, the problem that the measurement mask is difficult to manufacture and store due to overlarge reconstruction resolution can be solved, and the imaging resolution and the imaging rate are improved.

The invention discloses a single-photon non-vision-field target tracking system based on an unmanned aerial vehicle platform, which belongs to the field of non-vision-field imaging and is characterized in that a laser is connected with a scanning galvanometer assembly through a first nanosecond optical path switch and an optical fiber circulator to form an emission optical path for emitting laser pulses to relay reflecting surfaces corresponding to four predetermined positioning points; the scanning galvanometer assembly is connected with the photon detector through the collimating optical fiber, the optical fiber circulator and the second nanosecond optical path switch to form a receiving optical path capable of receiving echo photons; the main control module is electrically connected with the laser, the first nanosecond light path switch, the second nanosecond light path switch, the scanning galvanometer assembly, the photon detector, the time-to-digital converter and the high-frequency inertial measurement unit respectively, and can control each component to perform laser ranging, double-window gating, single-photon detection, inertial measurement unit sampling and timing according to a unified time sequence; and the three-dimensional coordinates of the current non-vision target are calculated by using the distance measurement data through an ellipsoid intersection solution method, so that non-vision target tracking is realized.

The present invention relates to a production 225 Closed cycle of Ac 226 Ra solution target system. The closed cycle 226 Ra solution target system includes solution type 226 Ra target, isotope target chamber, valve, 226 Ra solution circulation structure, radium-actinium separation structure, radium-lead separation structure, photon detection system I, photon detection system II, heat exchange system, vacuum radon evaporator and radon treatment system, among which, solution type 226 The Ra target includes a solution circulation pipeline and a radium-containing solution, and the radium-containing solution is contained in a closed solution circulation pipeline; the solution circulation pipeline includes a main loop pipeline and two branch pipelines; the photon detection system I, 226 The Ra solution circulation structure, vacuum radon evaporator, heat exchange system, valve and photon detection system II are sequentially arranged on the main loop pipeline; the radium-actinium separation structure and the radium-lead separation structure are respectively arranged on the two branch pipelines. 225 Preparation efficiency and yield of Ac.

The utility model relates to the technical field of photoelectric sensors, and discloses a photoelectric conversion device and electronic equipment, and the photoelectric conversion device comprises an SPAD device, a quenching module, a counting module, a time analog conversion module and a data processing module. When the count value is not greater than the preset value, the data processing module uses the count value to represent the ambient light intensity; and when the count value is greater than the preset value, calculating the average voltage corresponding to the average value of the pulse widths of the electric signals in the whole exposure period according to the accumulated value of the analog voltage, and representing the ambient light intensity by using the average voltage. According to the utility model, the counting module is firstly used for counting the number of photons received by the SPAD device, and when the counting value reaches a set value, the time analog conversion module is switched to represent the ambient light intensity, so that the dynamic range of photon detection is expanded without increasing the power consumption, the photons can be detected when the light intensity is relatively low or relatively high, and the detection efficiency is improved. And the condition of inaccurate counting caused by saturation of the counter due to increase of the light intensity is avoided.

The invention discloses a ranging communication fusion miniaturized system and method based on single photon detection. The system adopts a time division multiplexing common-path structure, and a ranging pulse sequence and a communication pulse sequence are sequentially transmitted in the same detection period to form a PPM modulation laser pulse chain. A single-photon detector is adopted to receive signals, background light interference is suppressed by combining a narrow-band filter and a time gating technology, and the type and boundary of a pulse sequence are identified through a signal demodulation and discrimination module. When the distance measurement pulse sequence is identified, the distance measurement path realizes distance measurement based on the round-trip time of the distance measurement pulse in the period; when a communication pulse sequence is identified, the communication path demodulates the PPM communication data. The method effectively decouples the contradiction between the distance measurement fuzzy and the communication rate, supports communication pulse high repetition frequency modulation while realizing non-fuzzy distance measurement, improves the distance measurement precision and the communication rate, and is suitable for free space communication, mobile robot platforms and other application scenes.

The invention discloses a side slope displacement monitoring method and device based on quantum single photons and a medium, and belongs to the technical field of displacement monitoring. Rectangular light pulses are emitted periodically, echo detection is completed by using a single photon detector, a photon counting time sequence is constructed, wavelet denoising and reconstruction processing is performed on the photon counting time sequence, main peak position offset, energy change and form distortion are extracted to match multiple types of feature vectors, and feature fusion and resolving are performed through a multi-source feature fusion BP neural network. And finally outputting a high-precision slope displacement result. According to the method, the quantum single-photon detection technology is combined with the wavelet denoising and neural network fusion algorithm, noise interference is effectively suppressed, the displacement feature extraction precision is improved, and the method is suitable for high-precision and long-distance slope micro-deformation real-time monitoring.

The invention discloses a quantum partial discharge detection system and method based on single photon measurement. The system comprises a photoelectric detection module and an information transmission and processing module which are connected in pairs. A free space light collection unit in the photoelectric detection module is used for converging photons of partial discharge radiation and guiding the collected photons to a classic weak light detection unit and a single photon detection unit respectively; the classic weak light detection unit is used for converting an optical signal into an electric pulse signal based on an internal photoelectric effect; the single-photon detection unit is used for detecting extremely weak light and even single-photon events and outputting discrete electric pulse signals. The classical weak light detection unit and the single photon detection unit operate in parallel, partial discharge optical detection with a wide dynamic range and a high signal-to-noise ratio is realized through a signal fusion and processing algorithm, electromagnetic interference is effectively inhibited, and a more comprehensive and reliable monitoring means is provided for evaluation of the insulation state of power equipment.

The invention discloses a gas leakage detection imaging device and method based on a single photon detection technology, and belongs to the technical field of gas detection and imaging. Aiming at the limitation problems of the existing gas leakage detection technology in the aspects of sensitivity, response speed, space imaging capability and anti-interference capability, nanosecond modulation control and synchronous photon counting are realized by utilizing an FPGA (Field Programmable Gate Array) through a visual gas detection imaging device combining an SPAD (Single Program Amplifier) array detector and a WMS modulation-demodulation mechanism; and the second harmonic of the absorption signal is further extracted by combining digital phase-locked amplification, so that gas leakage three-dimensional imaging with high spatial resolution, ppb-level sensitivity, strong background suppression capability and high time response is realized. The system has the advantages of high detection sensitivity, real-time imaging capability with high spatial resolution, high background light interference resistance and high signal-to-noise ratio, the demodulation method is novel, and the modular design has multi-gas compatibility and system expansibility.

Improvements in and relating to Photonics An optical switch for receiving an optical signal from an optical signal source and for outputting the optical signal comprises an optical router configured for routing the optical signal conditional on the detection of a single photon. The optical router comprises and optical resonator, a first optical pathway part comprising the optical resonator, and a second optical pathway part. An optical input coupling part receives the optical signal for coupling the received optical signal into the first optical pathway part and into the second optical pathway part. An optical modulator coupled to a single-photon detector unit outputs a detection signal in response to the detection of a single photon. The optical modulator is configured, in response to the detection signal, to modulate the refractive index of the optical resonator to change an optical phase shift incurred by the optical signal upon passage through the optical resonator such that an optical interference results in a routing of the output optical signal to one of the first and second optical pathway parts selected conditional on the detection of a single photon.

The invention relates to an Imaging sensor device in a stacked arrangement comprising:a pixel array tier comprising a plurality of pixel segments each having a plurality of pixels for photon detection each providing a digital pixel output;a processing tier comprising a number of processing cores each associated with one of the plurality of pixel segments to receive the pixel outputs of the pixels of the respective pixel segment, wherein the processing cores are each in bidirectional communication with one or more neighboring processing cores,wherein the processing cores are each configured to receive pixel outputs of the pixels of the associated pixel segments and to distribute processing of pixel outputs between the processing core and the at least one of the neighboring processing cores as neighboring processing cores.

The invention discloses a single-photon streak tube laser radar based on a delay difference. The single-photon streak tube laser radar comprises a delay pulse generator, a laser, a delay difference generation module, a beam shaping system and a receiving system. Wherein the delay difference generation module comprises an optical delay path and a time delay path, and can dynamically adjust the delay difference to adapt to near-field high-precision and far-field wide-range detection requirements; the light beam shaping system shapes the laser into a one-dimensional fan-shaped light beam, so that the divergence direction of the one-dimensional fan-shaped light beam is aligned with the time deflection dimension of the streak tube detector, and the energy utilization rate and the streak image quality are improved; the receiving system rejects noise and solves a target distance by using a cross-correlation noise reduction and weighted fusion algorithm through multi-stripe redundancy processing, so that the single-photon detection efficiency and the anti-interference capability are remarkably improved. According to the invention, the detection capability of the system on a long-distance weak reflection target, the reliability in a complex environment and the three-dimensional imaging precision are effectively improved.

The invention discloses a long-distance snapshot type spectral imaging radar system. The system comprises a light source, a projection objective lens, a photographic lens, a random mask, a grating, an SPAD and the like. Light emitted by the light source is projected to the surface of a target through the projection objective, and reflected light is sequentially processed by all the components and then detected by the SPAD. The SPAD is utilized to realize single photon detection, and the problem of spectrum detection at a long distance or under weak light and dark light is solved. Through specific light path design, a random mask plate and a grating are combined, and a light field is modulated and split. By means of a mathematical algorithm, for example, distance information is obtained based on multiple times of detection and statistics of arrival time, modulation, dispersion, integral operation and the like are carried out on a spectrum matrix, simultaneous detection of a target spectrum and the distance information is achieved, and compared with the prior art, more comprehensive and high-quality information can be obtained in a complex environment.

The invention relates to the technical field of photon detection imaging, in particular to a deep learning-based crossed strip-shaped anode single-photon detector imaging method, which comprises the following steps of: enabling incident photons to enter a crossed strip-shaped anode single-photon detector to obtain charge signals on a crossed strip-shaped anode in the detector; sampling the charge signal; inputting the obtained sampling data into a trained decoding network model to obtain a predicted position of an incident photon; establishing an imaging matrix, mapping the obtained prediction position into the imaging matrix, and performing interval division on the mapped imaging matrix; and carrying out gray value mapping on the number of photons in the divided intervals to obtain an imaging result. According to the invention, the neural network model is introduced to carry out computational imaging, so that the imaging quality of the cross strip-shaped anode single-photon detector is improved.

A quantum key distribution system is provided, including: a sending terminal, a measurement terminal, a receiving terminal, and at least one polarization controller. The sending terminal is configured to generate a quantum optical signal and receive a detection result. The measurement terminal includes a beam splitter and two single-photon detectors, the beam splitter is configured to generate two measurement optical signals based on the quantum optical signal, and the two single-photon detectors are configured to generate the detection result. The receiving terminal is configured to receive the detection result. The at least one polarization controller is provided in the sending terminal, the measurement terminal or the receiving terminal, and performs a polarization processing on the quantum optical signal or the detection result using a target transmittance matrix determined based on the detection result, so as to obtain a polarized quantum optical signal or a polarized detection result.

The invention relates to a data compression circuit and method suitable for a single photon avalanche diode array, and the circuit comprises a pixel array which is provided with M rows and N columns of pixels; the multi-stage compression circuit comprises a plurality of compression cache circuits connected in sequence, each stage of compression cache circuit comprises a plurality of first storage areas used for storing TDC data and address bits used for storing the positions of pixels corresponding to the TDC data in the pixel array, and the multi-stage compression circuit reads the TDC data of the pixel array line by line. And after multi-stage compression, the signals are output to a post-stage circuit. Compared with the prior art, the pixel data in a digital form is greatly compressed, the data transmission quantity is reduced, the data transmission bottleneck problem of a large-scale array is solved, and a key technical support is provided for a high-performance single-photon detection system.

The utility model provides a long wave pass optical filter and an integrated device, the film system structure of the optical filter is G / 0.5 H (LH) mL0.5 H / A, G is a substrate, H is a high refractive index film with a quarter wavelength thickness, L is a low refractive index film with a quarter wavelength thickness, m is a periodicity, and A is an air medium; the low-refractive-index film is a silicon oxide film; and the high-refractive-index film is an oxygen-doped germanium film. The integrated device comprises a silicon substrate, a fluorescence detection unit, a silicon oxide spacer layer and a long-wave-pass filtering film system, a fluorescence detection unit is arranged on the silicon substrate, and a silicon oxide spacing layer and a long-wave-pass filtering film system are sequentially arranged on the surface of the fluorescence detection unit; the thickness of the silicon oxide spacing layer is greater than the peak wavelength of the photon detection efficiency of the fluorescence detection unit. The film system structure of the long-wave-pass optical filter is simpler than that of a traditional band-pass filtering film system, the preparation process can be simplified, and the long-wave-pass optical filter is more suitable for process integration and process compatibility with other optoelectronic components.

Depth imaging system implementing the method of any of the previous claims comprising: a. an imaging device (4) comprising a matrix of pixels (1) each pixel comprising a photodetector (9) capable of detecting single photons impinging thereon and optics able to make an image of the field of view on the matrix of pixel (1), said single photon detector having a binary logic status of true when a photon is detected and a logic status of false when no photon is detected in a timeframe; b. a projector (5) able to project a pattern in a time window of less than 10 sec, preferably less than 1 sec; c. a controller synchronising the projector (5) time window and the imaging device timeframe; d. a logic determining, in use, the presence, during the timeframe, of contiguous pixels (11) in the true state, and calculating the depth profile corresponding to said contiguous pixels (11).

The invention provides a readout circuit of a dual-mode semiconductor single-photon detector, and relates to the technical field of single-photon detection, and the readout circuit comprises a control module which is used for generating a control signal based on an external gating signal and an avalanche detection signal; the amplification module is used for controlling the single-photon detector to exit from the Geiger mode when the control signal is in the low-level state; and controlling the single-photon detector to enter a Geiger mode when the control signal is in a high level state, the avalanche extraction module is used for extracting an avalanche signal to obtain a pulse type avalanche detection signal; under the condition that the gating signal is in the low-level state, the control module enables the control signal to be kept in the low-level state; and under the condition that the gating signal is in a high-level state, the control module enables the control signal to be in a low-level state based on the avalanche detection signal, quenches the avalanche signal and controls the control signal to be in a high-level state again after a preset delay duration.

The invention relates to a single-photon detector performance parameter measurement method, device, equipment and medium, and relates to the technical field of single-photon detection.The method comprises the steps that a total photon event count value in a first time domain range is calculated and determined, a post-pulse event count value in a second time domain range is calculated and determined, and the post-pulse event count value is calculated and determined; determining the post-pulse probability of each statistical subinterval in the statistical histogram according to the post-pulse event count value and the total photon event count value, and determining the post-pulse probability of the to-be-measured single-photon detector according to the post-pulse probability of each statistical subinterval; calculating and determining a first difference value between the second peak time and the first peak time so as to determine the dead time of the to-be-measured single-photon detector; and calculating and determining the time jitter of the to-be-measured single-photon detector according to the pulse width of the laser pulse, the time jitter of the synchronous pulse and the time jitter of the multi-event statistical histogram hour-to-digital converter. The time for measuring the performance parameters of the single-photon detector is greatly shortened.

The invention relates to a laser active imaging noise processing method, and belongs to the technical field of image processing and denoising. The single-photon denoising imaging processing method provided by the invention is designed based on the imaging characteristics of the single-photon array detector, the time characteristics of the echo data and the spatial correlation, and has a relatively good inhibition effect on background noise; the accurate target scene echo distance image and intensity image can be rapidly and accurately extracted from single-photon detection original data, and the method is extremely important for active imaging application of high-sensitivity single-photon array laser imaging.