44 results about "Photon counter" patented technology

The invention relates to the technical field of quantum sensing and optical instruments, and discloses an integrated scanning confocal microscope for diamond NV color center quantum sensing, which comprises a control module, an integrated circuit module, an integrated laser module and an integrated light path module, the control module is used for exciting a diamond NV color center, the integrated light path module realizes two-dimensional scanning of a laser beam on a sample focal plane through a galvanometer, an objective lens is used for collecting NV color center fluorescence, meanwhile, a single-photon counter and a camera are arranged, confocal detection and wide-field microscopic imaging are realized, and the integrated circuit module receives an instruction of the control module. The microscope can realize confocal scanning fluorescence imaging, optical detection magnetic resonance spectrum measurement and NV color center spin coherent control experiments, such as Rabian oscillation, Rahm, Haln echo and spin relaxation experiments, and provides comprehensive experimental ability for diamond NV color center quantum sensing.

The invention relates to the technical field of optical fiber sensing, and discloses a distributed optical fiber temperature sensing system based on photon counting and a measurement method, which can remarkably improve the sensing distance, the spatial resolution and the spatial positioning precision. According to the scheme, the method comprises the following steps: aiming at different segments of a sensing optical fiber, controlling the attenuation amount of a variable optical attenuator, and carrying out detection and time-dependent single photon counting on backscattered light from different segments on the sensing optical fiber by utilizing a single photon avalanche diode and a time-dependent single photon counter, and temperature distribution information of the sensing optical fiber is demodulated based on a time correlation single photon counting result.

The invention relates to the technical field of photoelectric detection, and provides a single-photon counter circuit for weak light detection based on a photomultiplier, and the single-photon counter comprises a photoelectric conversion circuit, a differential amplification circuit, a threshold comparison circuit and a signal shaping circuit. The photoelectric conversion circuit is composed of a photomultiplier, a high-voltage power supply circuit and a voltage division circuit, detects weak light signals and outputs two paths of current signals through photoelectric conversion. The differential amplification circuit carries out differential amplification on the two current signals through a differential amplifier. The threshold comparison circuit compares two input signals, filters out signals with the amplitude lower than 1 / 2 of a set threshold, and outputs a single-path effective signal. And the signal shaping circuit shapes the effective signal and finally outputs the effective signal in a TTL pulse mode. According to the single photon counter circuit for weak light detection, the background dark counting rate is low, the sensitivity is high, and the counting unit module specially used for digital pulse statistics is connected behind the single photon counter circuit for counting single photons.

Array single photon detection and two-dimensional camera common path fusion device and pixel matching method belong to the field of optical precision measurement. The array single photon detection and two-dimensional camera common path fusion device comprises a signal generator, a laser, an emitting optical system, a receiving optical system, a dichroic mirror, a two-dimensional camera, an array single photon detector, an array single photon counter and a data acquisition and processing fusion module. The method of the present application is as follows: the array single photon detection waveband pulsed laser and the two-dimensional camera sensing waveband ambient light returned by the target object are separated by using a common receiving optical path and a dichroic mirror to determine the pixel size and the number of the array single photon detector and the two-dimensional camera; the transmission light offset d is calculated according to the thickness of the dichroic mirror; the transmission light offset d is used as a correction factor to realize the pixel matching of the array single photon detection three-dimensional imaging and the two-dimensional camera image; the array single photon detection three-dimensional image and the two-dimensional camera image are superimposed, and the high resolution of the two-dimensional image is used to enrich the three-dimensional point cloud imaging information.

The invention relates to the technical field of in-situ photoelectric characterization systems, and provides an in-situ photoelectric characterization system.The in-situ photoelectric characterization system comprises a sample table, a light path structure, a light source assembly, a light source analysis assembly and a source meter device, light is projected to the light path structure through the light source assembly, so that the source meter device can record and form an electrical characteristic curve; meanwhile, at least one of a near-infrared spectrometer, a visible spectrometer, a single-photon counter, a monochromator coupled with a near-infrared photomultiplier and a monochromator coupled with a visible photomultiplier in the light source analysis assembly can analyze and detect the product, so that the detection operation can be effectively optimized, and the detection efficiency is improved.

A sensor for time of flight calculation, including a laser configured to emit a plurality of pulses of light at a target, one or more SPADs configured to detect a TDC trigger event, where the first TDC trigger event includes one or more photons detected as an initial pulse of light of the plurality of pulses of light is reflected to the one or more SPADs, a counter configured to count the one or more photons of the first TDC trigger event and generate a first histogram of the one or more photons at a first resolution, a global window processor configured to read the first histogram and detect a peak of the first histogram, and a global histogram processor configured to detect a peak of the second histogram, wherein the peak of the second histogram determines a distance between the sensor and the target.

The present application relates to a kind of X-ray detector photon arrival time mark precision measurement system and method.The present application system includes: signal generator, pulse X-ray generator, X-ray detector to be measured, time mark photon counter and processing module deployed on host computer constitute;Wherein, the signal generator is used to generate pulse signal, and respectively give pulse X-ray generator and time mark photon counter;The pulse X-ray generator is used to generate X-ray photon according to pulse signal;The X-ray detector to be measured is used to accept X-ray photon, and X-ray photon is converted into electric pulse, and is output to time mark photon counter;The time mark photon counter is used to time mark when receiving electric pulse electric pulse, and obtain the time interval between receiving pulse signal and electric pulse;The processing module is used to process time interval and obtain the time mark precision of X-ray detector to be measured.

The invention provides a large-range gas measuring device and method based on single-photon optical scanning. The large-range gas measuring device comprises a three-dimensional scanning holder, wherein a single-photon laser emitting unit and a single-photon detecting and counting unit are borne on the three-dimensional scanning holder; the three-dimensional scanning holder is used for adjusting the orientation of the single-photon laser emission unit and the single-photon detection counting unit pointing to the gas to be detected; the single-photon laser emission unit comprises a tunable wavelength laser module, a laser power amplifier module and an optical beam expanding collimation module; the single-photon detection and counting unit comprises a reflected light receiving telescope module, a narrow-band filter module, a single-photon detector and a single-photon counter; the central control processing unit comprises a control subunit, a data acquisition subunit and a data processing subunit and is used for controlling and receiving gas single photon detection data in a preset direction. The device has the advantages of low detection limit, strong anti-interference capability, high spatial resolution and the like, and is suitable for leakage detection of extremely low-concentration gas and large-range environment monitoring.

The application discloses a kind of three-dimensional positioning laser radar and its three-dimensional detection method, comprising: pulsed laser emits laser beam to target object, polarized beam splitter is respectively emitted to first lens and avalanche photodiode on laser beam, laser beam is shot to second lens after passing through first lens, is emitted to target object after passing through second lens, and avalanche photodiode is converted into electrical signal by received pulsed light signal, and electrical signal is transmitted to time correlation single photon counter;The light field signal of target object is collected by lens and sent to first beam splitter, and first, second beams are generated after being split by first beam splitter, and first second beams are split and handled by corresponding beam splitter, to obtain four-way beams;Four-way beams are transmitted by corresponding optical path respectively, and electrical signal is transmitted to four receiving ports of time correlation single photon counter;According to the four-way signal received, the three-dimensional space position prediction of target object is realized.

The application discloses a laser radar, which comprises a narrow-line-width multi-longitudinal-mode pulse laser, a photoelectric detector, a perforated mirror beam receiving system, a high-resolution narrow-line-width light splitting device and a plurality of single-photon detectors. The output beam of the narrow-line-width multi-longitudinal-mode pulse laser is emitted through the perforated mirror, and the photoelectric detector serves as a local signal. The echo signal photons reflected by a target are received through the receiving system, and are subjected to angle selection and spectral matching filtering through the light splitting device, and finally subjected to logical AND gate operation through the plurality of single-photon detectors, so that the final signal is simultaneously input into a time-correlation single-photon counter. The working performance of the photon counting laser radar in a strong noise environment is effectively improved, the false alarm probability of the laser radar is greatly reduced under the condition of ensuring the detection probability, the grating combined with the plurality of detectors can greatly reduce the background noise, the signal-to-noise ratio of the echo signal is greatly improved, and the detection capability of the laser radar is improved.

The present application relates to radioactive gas detection and sandstone type uranium exploration technical field, especially a soil radon emission rate measuring device and its sandstone type uranium ore prospecting method, including gas collecting mechanism, including PVC gas collecting cylinder, the top of PVC gas collecting cylinder is provided with sealing cover, the top of sealing cover is provided with atmospheric temperature and humidity pressure sensor and internet of things antenna respectively, the bottom of PVC gas collecting cylinder is installed with soil temperature and humidity sensor;Detection mechanism, it is cylindrical sealing mechanism, including chip storage module, photon counter.The present application realizes the underground in-situ stable measurement of soil radon emission rate by vertically burying PVC gas collecting cylinder in a certain depth under the ground, makes radon diffuse and accumulate naturally in the relatively closed and stable space from bottom to top, avoids the sealing problem and wind field interference under the open environment condition of the ground.In addition, cooperating with internet of things remote transmission technology, long-term continuous automatic observation and unattended can be realized, which significantly improves the field exploration efficiency.

The invention provides a large dynamic range sensing system based on single photon detection. The large dynamic range sensing system is characterized by comprising a pulse laser (1), a first coupler (21), a circulator (3), a detected optical fiber (4), an attenuator (5), an optical switch (6), a second coupler (22), a single photon detector (SPAD) (7), a quenching circuit (8), a time-dependent single photon counter (TCSPC) (9) and a system control and data processing module (10). The method has the capability of detecting photon-magnitude echo signals, greatly improves the dynamic range and spatial resolution of the system, and can be widely applied to the field of optical fiber sensing.

The application provides a photon counting scanning three-dimensional penetration imaging method based on asynchronous polarization modulation. In view of the scattering effect and attenuation of a strong scattering medium on a light signal, a point-to-point scanning imaging mechanism is adopted to avoid image blurring caused by the scattering effect, and a single-pixel photon counter is used to capture weak ballistic photon signals. The time of flight of the ballistic photon signal is calculated by a polarization modulation ranging method, and the depth blurring problem introduced by the asynchronous polarization modulation is corrected by a time reshaping method, and finally the relative depth image of the target object is reconstructed. The method can realize three-dimensional imaging of the target object through the strong scattering medium, the imaging effect is clear, and the method has robustness to different strong scattering media, and provides convenience for three-dimensional photon counting imaging in a scattering environment.

The application discloses a method for measuring surface contamination of long-distance alpha radioactive material, which comprises the steps of measuring long-distance alpha radioactive point source and measuring long-distance alpha surface contamination count rate. The measurement of long-distance alpha radioactive point source comprises intrinsic detection efficiency of alpha particles, collection efficiency calculation and detection efficiency calculation; the measurement of long-distance alpha surface contamination count rate comprises establishing a contamination count rate model, calculating the mean value of point source detection efficiency in each place in a detection area, calculating the expression of the radius R of the detection area D and performing a least square fitting process on the change relation of the radioactive surface source detection efficiency with the opening angle of a shielding body. The application detects fluorescent photons by using a single photon counter, and converts the measured count rate value into the count rate of surface contamination required in the operation intervention level by using the established model.

The present application relates to the technical field of semiconductor electronic device, and particularly relates to a self-quenching multi-pixel photon counter and a preparation method thereof. The counter comprises: a substrate; a first epitaxial layer provided on the substrate, which is a heavily doped silicon carbide layer; a second epitaxial layer provided on the first epitaxial layer, which is a lightly doped silicon carbide layer; an electric field control structure comprising M recessed patterned structures (M >= 2), which are discrete on the second epitaxial layer; a first ohmic contact layer located on the upper layer of the second epitaxial layer and below the electric field control structure, covering the whole; a first metal layer provided on the first ohmic contact layer in a unit network shape, forming ohmic contact and parallel connection of each patterned structure; and a second metal layer provided on the lower surface of the substrate and / or in the first epitaxial layer, forming ohmic contact with the same. The present application provides a new technical route for the preparation and application of the weak ultraviolet light detection under extreme conditions and the large-scale multi-pixel photon counter.

The application discloses a wavelength-tunable non-local dispersion compensation device, comprising: a laser; a waveguide connected to the laser, used for exciting the waveguide by the continuous laser to generate a pair of preset-wavelength and mutually-perpendicular polarization photons, wherein the preset wavelength is obtained according to a dispersion compensation formula; a polarization beam splitter connected to the waveguide, having a first output end and a second output end, used for dividing the polarization photons into signal photons and idler photons to be output from the first output end and the second output end respectively; a first single-photon detector and a second single-photon detector; and a time-correlated single-photon counter, used for measuring the width of the time-domain coincidence peak of the signal photons output by the first single-photon detector and the idler photons output by the second single-photon detector to evaluate the dispersion compensation effect. The application adjusts the wavelength to compensate the dispersion, can realize the dynamic adjustment of the dispersion without replacing the dispersion compensation module, and does not need to interrupt the fiber link, thereby enhancing the system stability.

Systems, devices, methods, and techniques for photonic quantum information processing are provided. In one aspect, a photonic integrated circuitry for counting one or more photons includes: a plurality of single-photon counters each including a single-photon avalanche diode (SPAD) and one or more waveguides arranged to optically couple the one or more photons to the plurality of single-photon counters. A count of the plurality of single-photon counters is greater than a count of the one or more photons to be counted. The plurality of single-photon counters and the one or more waveguides are formed on a substrate.

The application discloses a perovskite crystal gamma ray photon counter structure and a preparation method thereof. The perovskite crystal gamma ray photon counter structure comprises a perovskite crystal with a band gap gradient distribution and without doping, a p-type perovskite layer and an n-type perovskite layer. The perovskite crystal has opposite first and second surfaces, the p-type perovskite layer is arranged on the first surface, and the n-type perovskite layer is arranged on the second surface. The energy band gap of the perovskite crystal gradually increases or decreases from the first surface to the second surface. The perovskite crystal with a band gap gradient distribution and without doping between the p-type perovskite layer and the n-type perovskite layer improves the lattice matching rate between the crystal layers, effectively inhibits ion migration of the perovskite, and reduces the baseline drift and noise of a detection signal.

The application provides a measuring darkroom device for an optoelectronic nose, and relates to the technical field of breath gas detection. The measuring darkroom device for the optoelectronic nose comprises a darkroom box, a light sensor array, a motion mechanism, a photon counter, a controller and an upper computer. The VOC component in the breath gas can be subjected to a catalytic chemiluminescence reaction on a catalytic coating through each light sensor of the light sensor array in the darkroom box. The photon counter is moved to each light sensor under the driving of the motion mechanism, so that the photon counter measures the light output by each light sensor. The measuring data is sent to the upper computer through the controller. Since the light sensor based on the catalytic chemiluminescence principle has high detection sensitivity, the detection sensitivity of the electronic nose can be improved, and the VOC content in the breath gas can be detected.

The invention relates to a three-dimensional point cloud generation method and device, and the method comprises the steps: generating and transmitting a coding laser pulse string with the intensity increasing along with the time in a single distance measurement period; the dynamic anti-saturation control circuit of each pixel unit monitors a count value of a photon counter of the pixel unit in real time aiming at a coding laser pulse string, and immediately turns off the photon detection function of the pixel unit when the count value reaches or exceeds a preset saturation threshold value for the first time in a distance measurement period; according to the final count value of each pixel unit, based on a pre-stored deviation compensation model, performing deviation compensation on the corresponding effective timestamp, and calculating an accurate distance value; the deviation compensation model is used for correcting flight time measurement deviation caused by response differences of pulses with different intensities in the coded laser pulse string; and fusing the accurate distance values of all the pixel units and the corresponding spatial orientation information to generate a three-dimensional point cloud, thereby solving the technical problems of strong echo saturation and weak echo leak detection in the prior art.

The application discloses a kind of micro automatic focusing methods based on single-photon counting, it is related to the field of automatic focusing, including using photon counter to obtain multi-channel signal, according to multi-channel signal single-pixel imaging is carried out, and the gray scale of sample is determined;By using definition evaluation operator and gray scale are convolved, the definition evaluation value of this position is obtained, the definition evaluation value of current position and last position is compared, and the preliminary focus position is determined, and the nanometer piezoelectric translation stage is moved to preliminary focus position;Preliminary focus position is used as the center point of next search interval, and the target area is determined, and the improved hill-climbing search algorithm is used to adjust the target area, and the final focus position is determined;Nanometer piezoelectric translation stage is moved from preliminary focus position to final focus position, and automatic focusing is realized.

This invention discloses a small lidar for detecting water vapor in the lower troposphere. Using the 935.6845nm strong absorption line as a reference, a 20GHz semiconductor microwave synthesizer is used for phase-locked loop (PLL) and frequency stabilization to maintain the emission wavelength of the front-stage semiconductor laser at a point of 935.7429nm on the slope of the suitable water vapor absorption line, adapting to the physical state where most water vapor is distributed within the boundary layer. The beginning of an optical fiber delay line is connected to the common transmit / receive end of the circulator, with the end of the delay line located at the telescope focal point. All end faces of the delay line are non-perpendicular. A gating time is defined as the period from the start of the emitted pulse until the pulse completely leaves the optical fiber delay line, which puts the photon counter into a dormant state to protect it, thereby shortening the blind zone. The period and duty cycle of the 935nm emitted laser pulse are controlled by another periodic laser pulse with a wavelength of 905nm.

The invention provides an in-plane multi-point parallel vibration measurement device and method based on array single-photon detection, and relates to the field of laser measurement, and the in-plane multi-point parallel vibration measurement device comprises a laser, a transmitting optical system, a receiving optical imaging system, an array single-photon detector, an array single-photon counter and a data processing module. A laser beam output by the laser is converted into a parallel coherent light beam by the emission optical system, the light beam is reflected after irradiating a target object, and the reflected light beam is imaged on the array single-photon detector by the receiving optical imaging system; the array single-photon detector converts reflected light intensity into electric signals and inputs the electric signals into the data processing module, and the data processing module calculates in-plane multi-point parallel vibration frequency information of the target object. Vibration information of a long-distance in-plane multi-point parallel target is imaged to a focal plane of an imaging optical system in a non-contact mode, and in-plane multi-point parallel vibration frequency information of the target object is acquired and calculated by a data processing module.

The invention discloses a data transmission method and system for a time-dependent single photon counter, and the method comprises the steps: dividing data into a plurality of data blocks at a transmitting end, distributing transmitting ports for the plurality of data blocks, and enabling each transmitting port to independently use a physical channel of a network card; therefore, compared with a traditional single-channel transmission technology based on an optical module, after the data are partitioned, the partitioned data are transmitted to the data receiving end through different channels, the multi-channel characteristic of an Ethernet network card based on the optical module can be fully utilized, and therefore in the TCSPC data acquisition process, the data transmission efficiency is improved. According to the design, the bandwidth of the network card can be fully utilized by single equipment, so that high-speed transmission of data can be realized through multiple channels, and the bandwidth bottleneck of the traditional technology is broken; on the basis, high-speed transmission of photon data is realized, so that the method is very suitable for large-scale application and popularization.

The invention provides a general photon counter. The general photon counter comprises a photon pulse digital input circuit, a photon pulse analog input circuit, a pulse discriminating circuit, a discriminating level generating circuit and an FPGA (Field Programmable Gate Array), the photon pulse digital input circuit is used for receiving a standard digital level photon pulse signal and outputting the standard digital level photon pulse signal to the FPGA; the photon pulse analog input circuit is connected with the pulse discriminator circuit; the discriminating level generating circuit is controlled by the FPGA and provides adjustable discriminating voltage for the pulse discriminating circuit; the pulse discriminating circuit compares the processed analog photon pulse signal with the discriminating voltage, outputs a pulse higher than the discriminating voltage as a digital signal and sends the digital signal to the FPGA; the FPGA is respectively connected with the photon pulse digital input circuit, the pulse discriminating circuit, the discriminating level generating circuit, the parameter configuration communication bus and the counting result output bus. According to the invention, missed metering cannot be caused.

The invention discloses a moving target single-photon laser ranging system and a trajectory extraction method, belongs to the technical field of laser ranging, and aims to solve the technical problem that an existing single-photon ranging method is only suitable for ranging a constant-speed linear moving target or a static target. The device comprises a tracking camera, a tracking turntable, a computer, a laser, a beam expander, a laser receiving mirror group, a single-photon detector and a photon counter, the tracking camera, the computer, the laser, the beam expander, the laser receiving lens group, the single-photon detector and the photon counter are all placed on the tracking turntable, the tracking camera and the tracking turntable are respectively connected with the computer, the beam expander and the laser are coaxially arranged, the laser is connected with the photon counter, the laser receiving lens group and the single-photon detector are coaxially arranged, and the single-photon detector is connected with the single-photon counter. The single photon detector is connected with the photon counter; and distance measurement can be carried out on not only an object in uniform linear motion but also an object in uniform variable motion.

Provided in the present application is an in situ optoelectronic characterization system (1000). The in situ optoelectronic characterization system (1000) comprises a sample stage (100), an optical path structure (200), a light source component (300), a light source analysis assembly (400), and a source meter device (500), wherein the light source component (300) is used to project light onto the optical path structure (200), so that the source meter device (500) can record and form an electrical characteristic curve; moreover, at least one of a near-infrared spectrometer (410), a visible spectrometer (420), a single-photon counter (430), a monochromator (440) coupled with a near-infrared photomultiplier tube, and a monochromator (450) coupled with a visible photomultiplier tube in the light source analysis assembly (400) can analyze and detect a product, thereby effectively optimizing a detection operation and improving the detection efficiency.

A quantum non-demolition photon counter includes a quantum system, a processor, and a memory. The quantum system includes photons. The memory includes instructions stored thereon, which, when executed by the processor, cause the system to: couple an initial photonic state of the quantum system to an array of atoms in a |g-|e transition; store the photon(s) in the array using a classical control field acting on the |s-|e transition; oscillate the array between the states |s and |r, where |r is a Rydberg state; and perform a projective measurement of a presence of a Rydberg excitation by indirectly and progressively measuring a photon number n by directly and repeatedly measuring the presence of the Rydberg excitation after under Ĥ for a predetermined period of time. The array of atoms is initially in a ground state |g and |e is an excited state.

The invention relates to a low power single photon avalanche diode photon counter using peak current suppression techniques. The invention relates to a sensor for time-of-flight calculation, comprising: a laser configured to emit a plurality of light pulses at a target; one or more SPAD configured to detect a TDC trigger event, where a first TDC trigger event includes detecting one or more photons when an initial light pulse of the plurality of light pulses is reflected to the one or more SPAD; a counter configured to count the one or more photons of the first TDC trigger event and generate a first histogram of the one or more photons at a first resolution; a global window processor configured to read the first histogram and detect a peak of the first histogram; and a global histogram processor configured to detect a peak of a second histogram, where the peak of the second histogram determines a distance between the sensor and the target.