Method and apparatus for measuring detection efficiency of single-photon detector, device, and medium

Abstract

The present application relates to a method and apparatus for measuring the detection efficiency of a single-photon detector, a device, and a medium. The method comprises: acquiring time interval data generated by a single-photon detector under measurement in an event-refreshed time-to-digital converter under the action of each light pulse at the same wavelength, and determining by means of calculation a probability density of the time interval data falling within a statistical bin of a preset statistical histogram, so as to determine a temporal photon probability distribution of said single-photon detector under the irradiation of each light pulse; using a preset photoelectron counting model to fit the temporal photon probability distribution, so as to determine the average number of photoelectrons detected by said single-photon detector under the action of a single light pulse; and determining the detection efficiency of said single-photon detector on the basis of the average number of incident photons and the average number of photoelectrons, so as to complete the measurement of the detection efficiency of the single-photon detector. The present application greatly improves the measurement efficiency, and also significantly improves the measurement accuracy of a detection efficiency spectrum.

Description

Single-photon detector detection efficiency measurement method, device, equipment and medium TECHNICAL FIELD

[0001] The present application relates to the technical field of single-photon detection, and in particular to a single-photon detector detection efficiency measurement method, a corresponding device, an electronic device and a computer readable storage medium. BACKGROUND

[0002] Single-photon detectors have been widely used in the fields of quantum information, laser radar, fluorescence analysis and other cutting-edge scientific technologies due to their important characteristics such as single-photon response sensitivity and picosecond-level time resolution. Different application scenarios have different requirements for the performance of single-photon detectors. Accurate and reliable measurement of the performance parameters of single-photon detectors is a prerequisite for selecting appropriate single-photon detectors for specific applications. Detection efficiency is the most core performance parameter of single-photon detectors, which is used to characterize the ability of single-photon detectors to convert the number of incident photons into the number of detectable electrical pulses.

[0003] Currently, there are two main methods for measuring the detection efficiency of single-photon detectors: the correlated photon method and the standard detector method. Both the correlated photon method and the standard detector method use a counter to measure the rate of single-photon detector output pulses under light conditions and calculate the detection efficiency accordingly. However, due to the non-ideal characteristics of single-photon detectors such as dark counts and afterpulses, the actual measured counts contain not only photon-induced counts but also dark pulse and afterpulse counts. In addition, single-photon detectors also have a dead time effect, which causes the actual measured count rate to be less than the true photon count rate. In order to obtain the true photon count rate, dark count rate, afterpulse probability, dead time and accurate correction model need to be measured and corrected, which means that additional measurements and corrections are required. These additional measurements and corrections not only greatly increase the complexity of detection efficiency measurement, but also introduce additional measurement errors.

[0004] In summary, the existing single-photon detector detection efficiency measurement method needs to correct the actual measured count rate for dark counts, afterpulses and dead time in order to obtain the true photon count rate. These additional measurements and corrections not only greatly increase the complexity of detection efficiency measurement, but also introduce additional measurement errors. The present applicant made corresponding explorations to solve this problem. SUMMARY

[0005] The present application aims to solve the above problems and provides a single-photon detector detection efficiency measurement method, a corresponding device, an electronic device and a computer readable storage medium.

[0006] To achieve the various purposes of the present application, the present application adopts the following technical solutions:

[0007] A single photon detector detection efficiency measurement method is proposed for one of the purposes of the present application, comprising:

[0008] In response to the single photon detector detection efficiency measurement instruction, the light powers of the first calibration photodiode and the second calibration photodiode under the irradiation of each monochromatic light-emitting diode in the monochromatic light-emitting diode array during the calibration measurement process are obtained to determine the calibration coefficient of each monochromatic light-emitting diode;

[0009] According to the calibration coefficient, the light-sensitive area of the single photon detector to be measured, the light-sensitive area of the second calibration photodiode, and the light power of the first calibration photodiode during the detection efficiency measurement process of the single photon detector to be measured, the average number of incident photons on the light-sensitive area of the single photon detector to be measured under the irradiation of each monochromatic light-emitting diode is calculated and determined;

[0010] The time interval data generated by the single photon detector to be measured under the action of each light pulse of the same wavelength in the event refresh time converter is obtained, and the probability density of the time interval data falling into a preset statistical sub-interval of a statistical histogram is calculated and determined to determine the time-domain photon probability distribution of the single photon detector to be measured under the irradiation of each light pulse;

[0011] A preset photoelectron counting model is used to fit the time-domain photon probability distribution to determine the average number of photoelectrons detected by the single photon detector to be measured under the action of a single light pulse;

[0012] The detection efficiency of the single photon detector to be measured is determined based on the average number of incident photons and the average number of photoelectrons to complete the measurement of the detection efficiency of the single photon detector.

[0013] Optionally, the step of obtaining the light powers of the first calibration photodiode and the second calibration photodiode under the irradiation of each monochromatic light-emitting diode in the monochromatic light-emitting diode array during the calibration measurement process to determine the calibration coefficient of each monochromatic light-emitting diode comprises:

[0014] The light powers of the first calibration photodiode and the second calibration photodiode during the calibration measurement process are determined under the irradiation of each monochromatic light-emitting diode in the monochromatic light-emitting diode array;

[0015] Based on the ratio between the light power of the second calibration photodiode and the light power of the first calibration photodiode, the calibration coefficient of each monochromatic light-emitting diode is determined.

[0016] Optionally, the step of calculating the average number of incident photons of each single-color light-emitting diode irradiated onto the light-sensitive area of the single-photon detector to be measured based on the scaling coefficient, the light-sensitive area of the single-photon detector to be measured, the light-sensitive area of the second calibration photodiode, and the light power of the first calibration photodiode in the detection efficiency measurement process of the single-photon detector to be measured comprises:

[0017] obtaining the light-sensitive area of the single-photon detector to be measured, the light-sensitive area of the second calibration photodiode, the scaling coefficient of each single-color light-emitting diode, the light power of the first calibration photodiode in the detection efficiency measurement process of the single-photon detector to be measured, the center wavelength of each single-color light-emitting diode, and the frequency of the light pulse emitted by each single-color light-emitting diode;

[0018] calculating a first ratio between the center wavelength of each single-color light-emitting diode and the frequency of the light pulse emitted by each single-color light-emitting diode;

[0019] calculating a second ratio between the light-sensitive area of the single-photon detector to be measured and the light-sensitive area of the second calibration photodiode;

[0020] calculating a first product of the scaling coefficient of each single-color light-emitting diode and the light power of the first calibration photodiode in the detection efficiency measurement process of the single-photon detector to be measured;

[0021] calculating the average number of incident photons of each single-color light-emitting diode irradiated onto the light-sensitive area of the single-photon detector to be measured based on the first ratio, the second ratio, and the first product.

[0022] Optionally, the step of calculating the time interval data generated by the single-photon detector to be measured under the action of each light pulse at the same wavelength in the event refresh time-to-digital converter and determining the probability density of the time interval data falling into a preset statistical sub-interval of a statistical histogram to determine the time-domain photon probability distribution of the single-photon detector to be measured under the irradiation of each light pulse comprises:

[0023] recording the time interval data generated by the single-photon detector to be measured under the action of each light pulse using the event refresh time-to-digital converter;

[0024] determining the width of each statistical sub-interval of the statistical histogram, wherein each statistical sub-interval represents a time interval range, and the width of the statistical sub-interval is greater than the width of the pulse emitted by each single-color light-emitting diode;

[0025] distributing the time interval data generated by the single-photon detector to be measured under the action of each light pulse into each statistical sub-interval to construct the statistical histogram;

[0026] determining a total number of events in the statistical histogram and a count of time interval ranges of each statistical sub-interval, obtaining a probability density of the time interval range of each statistical sub-interval based on a ratio between the count of the time interval range of each statistical sub-interval and the total number of events in the statistical histogram, to determine a time-domain photon probability distribution of the single-photon detector under irradiation of each light pulse.

[0027] Optionally, the photoelectron counting model is:

[0028]

[0029] wherein j represents a jth statistical sub-interval of the statistical histogram; y = exp(-R dn Δt) represents a probability that the single-photon detector does not detect a dark pulse within a time interval range of each statistical sub-interval, R dn represents a dark pulse counting rate, and Δt represents the time interval range of each statistical sub-interval; z = y exp(-μ) represents a probability that the single-photon detector does not detect both a photon-induced pulse and a dark pulse within the time interval range of each statistical sub-interval, and μ represents an average number of photoelectrons detected by the single-photon detector under action of a single light pulse; j dark represents a number of statistical sub-intervals contained between a delay time between a start pulse of the time-to-digital converter and the light pulse and a refresh time of the event; m represents a mth photon probability peak in the statistical histogram; n represents a number of statistical sub-intervals contained between photon probability peaks with a period of T p ; and p ph (j) represents the time-domain photon probability distribution.

[0030] Optionally, the step of determining the detection efficiency of the single-photon detector to be measured based on the average number of incident photons and the average number of photoelectrons includes:

[0031] determining an average number of incident photons of each monochromatic light-emitting diode irradiated onto a light-sensitive region of the single-photon detector to be measured and an average number of photoelectrons detected by the single-photon detector to be measured under action of a single light pulse;

[0032] determining the detection efficiency of the single-photon detector to be measured based on a ratio between the average number of photoelectrons detected by the single-photon detector to be measured under action of a single light pulse and the average number of incident photons of each monochromatic light-emitting diode irradiated onto the light-sensitive region of the single-photon detector to be measured.

[0033] Optionally, the light-sensitive area of the second calibration photodiode is in the same position as the light-sensitive area of the single-photon detector to be measured, the wavelengths of each monochromatic light-emitting diode in the array of monochromatic light-emitting diodes are different, and the single-photon detector to be measured includes a photomultiplier tube or a single-photon avalanche diode.

[0034] A single-photon detector detection efficiency measurement device is provided to achieve another object of the present application, comprising:

[0035] A scaling factor determination module is configured to obtain the optical power of the first calibration photodiode and the second calibration photodiode under the irradiation of each monochromatic light-emitting diode in the array of monochromatic light-emitting diodes during the scaling measurement process in response to a single-photon detector detection efficiency measurement instruction, so as to determine the scaling factor of each monochromatic light-emitting diode.

[0036] An incident photon number determination module is configured to calculate and determine the average incident photon number of each monochromatic light-emitting diode irradiated onto the light-sensitive area of the single-photon detector to be measured according to the scaling factor, the light-sensitive area of the single-photon detector to be measured, the light-sensitive area of the second calibration photodiode, and the optical power of the first calibration photodiode during the detection efficiency measurement process of the single-photon detector to be measured.

[0037] A probability distribution determination module is configured to obtain time interval data of the single-photon detector to be measured generated under the action of each light pulse at the same wavelength in the event refresh time converter, calculate and determine the probability density of the time interval data falling into a preset statistical sub-interval of a statistical histogram, so as to determine the time-domain photon probability distribution of the single-photon detector to be measured under the irradiation of each light pulse.

[0038] A photoelectron number determination module is configured to fit the time-domain photon probability distribution by using a preset photoelectron counting model, so as to determine the average number of photoelectrons detected by the single-photon detector to be measured under the action of a single light pulse.

[0039] A detection efficiency determination module is configured to determine the detection efficiency of the single-photon detector to be measured based on the average incident photon number and the average number of photoelectrons, so as to complete the measurement of the detection efficiency of the single-photon detector.

[0040] An electronic device is provided to achieve another object of the present application, comprising a central processing unit and a memory, and the central processing unit is configured to invoke a computer program stored in the memory to execute the steps of the single-photon detector detection efficiency measurement method described in the present application.

[0041] Another object of the present application is to provide a computer readable storage medium storing a computer program in the form of computer readable instructions, which is implemented according to the single-photon detector detection efficiency measurement method. When the computer program is invoked and run by a computer, the steps included in the corresponding method are executed.

[0042] Compared with the prior art, in order to obtain a real photon counting rate, the single-photon detector detection efficiency measurement method in the prior art needs to correct the actual measured counting rate for dark counts, after-pulse and dead time. These additional measurements and corrections not only greatly increase the complexity of the detection efficiency measurement, but also introduce additional measurement errors and other problems. The present application includes but is not limited to the following beneficial effects:

[0043] First, the event refresh time converter only measures the arrival time of the first event (i.e. the end pulse) after the start pulse, and the start and end pulses of the event refresh time converter are the synchronization pulse of the light source and the pulse output by the single-photon detector, respectively. In this measurement mode, the dead time of the single-photon detector does not affect the detection probability of the first event.

[0044] Second, the light pulse period is much larger than the duration of the single-photon detector after-pulse probability, so as to ensure that the probability of after-pulse events occurring within the duration of the light pulse is zero.

[0045] Third, the established photoelectron counting model is used to fit the time-domain probability distribution measured by the event refresh time converter, so as to simultaneously obtain the average number of detected photoelectrons and the dark counting rate, without the need for prior measurement and correction of the dark counting effect of the single-photon detector.

[0046] Further, the single-photon detector detection efficiency measurement method provided by the present application can quickly and accurately measure the detection efficiency spectrum of the single-photon detector in a wide spectral range, without the need for additional measurement and correction of the dead time, dark counting rate and after-pulse probability of the single-photon detector. This greatly reduces the amount of data that needs to be directly measured, avoids introducing additional measurement errors, greatly improves the measurement efficiency, and significantly improves the measurement accuracy of the detection efficiency spectrum. BRIEF DESCRIPTION OF DRAWINGS

[0047] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, in which:

[0048] FIG. 1 is an exemplary network architecture adopted by the single-photon detector detection efficiency measurement system of the present application;

[0049] FIG. 2 is a schematic diagram of the timing of measuring the detection efficiency of the single-photon detector based on the event refresh time converter in the embodiment of the present application;

[0050] Fig. 3 is a flow diagram of a method for measuring the detection efficiency of a single photon detector according to an embodiment of the present application;

[0051] Fig. 4 is a flow diagram of a method for determining the scaling factor of each monochromatic light emitting diode according to an embodiment of the present application;

[0052] Fig. 5 is a flow diagram of a method for determining the average number of incident photons of each monochromatic light emitting diode on the light sensitive area of the single photon detector to be measured according to an embodiment of the present application;

[0053] Fig. 6 is a flow diagram of a method for determining the time domain photon probability distribution of the single photon detector to be measured under the irradiation of each light pulse according to an embodiment of the present application;

[0054] Fig. 7 is a schematic diagram of the time domain probability distribution of a silicon single photon avalanche diode under the irradiation of a 670 nm monochromatic light emitting diode pulse according to an embodiment of the present application;

[0055] Fig. 8 is a flow diagram of a method for determining the detection efficiency of the single photon detector to be measured according to an embodiment of the present application;

[0056] Fig. 9 is a schematic diagram of a principle block diagram of a detection efficiency measuring device of a single photon detector according to an embodiment of the present application;

[0057] Fig. 10 is a schematic diagram of the structure of a computer device according to an embodiment of the present application.

[0058] Reference signs:

[0059] 101 pulse generator module, 102 programmable switch selection circuit module, 103 monochromatic light emitting diode array, 111 integrating sphere, 121 single photon detector to be measured, 122 voltage source, 131 first calibration photodiode, 132 power meter, 141 event refresh time converter module, 151 computer terminal device, 161 dark box. DETAILED DESCRIPTION

[0060] The embodiments of the present application are described in detail below with reference to the accompanying drawings. The embodiments described below are examples for explaining the present application and should not be construed as limiting the present application.

[0061] It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, "connected," "coupled," and / or "coupling," can include both direct connections and / or indirect connections (i.e., via one or more other elements). As used herein, "connection" or "coupling" can include a wireless connection or a wireless coupling. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0062] Those skilled in the art will appreciate that unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an overly legal sense unless expressly so defined herein.

[0063] Those skilled in the art will understand that, as used herein, the terms "client," "terminal," and "terminal device" include both devices that are solely wireless signal receivers and devices that have both receiving and transmitting hardware that can communicate bi-directionally over a bi-directional communication link. Such devices can include cellular or other communication devices with single-line or multiple-line displays, or no display, Personal Communications Service (PCS) devices that can combine a voice and data function, Personal Digital Assistants (PDAs) that can include a radio frequency receiver, pagers, Internet / intranet access, Web browsers, organizers, calendars, and / or a Global Positioning System (GPS) receiver, conventional laptop and / or palmtop computers, or other devices that have a radio frequency receiver. The terms "client," "terminal," and "terminal device" as used herein can be portable, transportable, installed in a vehicle (aeronautical, maritime, and / or land), or adapted for and / or configured for local and / or distributed operation on Earth and / or any other location in space. The terms "client," "terminal," and "terminal device" as used herein can also be a communication terminal, an Internet terminal, a music / video playing terminal, such as a PDA, a Mobile Internet Device (MID), and / or a mobile phone with music / video playing function, a smart television, a set-top box, and the like.

[0064] As used herein, the terms "server," "client," "service node," and the like refer to hardware that has the equivalent capability of a personal computer, i.e., an electronic device having a central processing unit (including an arithmetic unit and a controller), a memory, an input device, and an output device, and the like necessary components disclosed by the Von Neumann principle. A computer program is stored in the memory, the central processing unit calls the program stored in the external memory into the memory and runs it, executes the instructions in the program, and interacts with the input and output devices, thereby completing a specific function.

[0065] It should be noted that the concept of "server" in the present application can also be extended to the case of a server cluster. According to the principle of network deployment understood by those skilled in the art, the servers should be logically divided, and in physical space, these servers can be independent of each other but can be called through an interface, or can be integrated into a physical computer or a computer cluster. Those skilled in the art should understand this variation and should not be restricted by the implementation of the network deployment of the present application.

[0066] One or more technical features of the present application, unless explicitly specified, can be deployed on a server for implementation and accessed by a client remotely calling an online service interface provided by the server, or can be directly deployed and run on a client for implementation.

[0067] The neural network model referred to or possibly referred to in the present application, unless explicitly specified, can be deployed on a remote server and remotely called by a client, or can be deployed on a client with sufficient device capability for direct calling. In some embodiments, when it is run on a client, its corresponding intelligence can be obtained through transfer learning, so as to reduce the requirement for client hardware running resources and avoid excessive occupation of client hardware running resources.

[0068] The various data involved in the present application, unless explicitly specified, can be remotely stored on a server or stored on a local terminal device, as long as it is suitable for being called by the technical solutions of the present application.

[0069] Those skilled in the art should know that the various methods of the present application, although based on the same concept and described to present commonality among them, are independently executable unless otherwise specified. Similarly, for each embodiment disclosed in the present application, it is based on the same inventive concept, so the same concept is understood to be equivalent, and although the concept is expressed differently, it is only a suitable transformation for convenience.

[0070] Unless it is explicitly stated that the embodiments disclosed in the present application are mutually exclusive, the technical features involved in each embodiment can be combined flexibly to construct new embodiments, as long as such combination does not deviate from the spirit of the present application and can meet the needs of the prior art or solve some aspects of the deficiencies in the prior art. For this variation, those skilled in the art should know.

[0071] Referring to FIG. 1, the single photon detector detection efficiency measurement method of the present application can be implemented based on a single photon detector detection efficiency measurement system of an event refresh time-to-digital converter, which comprises a pulse generator module 101, a monochromatic light emitting diode programmable switch selection circuit module 102, a monochromatic light emitting diode (LED) array 103, an integrating sphere 111, a single photon detector to be measured 121, a voltage source 122, a first calibration photodiode 131, a power meter 132, an event refresh time-to-digital converter (TDC) module 141, a computer terminal device 151, and a dark box 161. The solid lines with one-way arrows represent light propagation paths, and the solid lines represent electrical connections.

[0072] In some embodiments, the single photon detector to be measured 121 includes, but is not limited to, a photomultiplier tube or a single photon avalanche diode, such as a silicon (Si) single photon avalanche diode, an indium gallium arsenide (InGaAs) single photon avalanche diode, etc. A silicon (Si) single photon avalanche diode is selected as an example for illustration. Since the spectral region of the silicon (Si) single photon avalanche diode response covers the visible and near-infrared regions, 16 monochromatic light emitting diodes with a wavelength range of 400-1000 nm are selected to be integrated together to form a 4´4 monochromatic light emitting diode (LED) array.

[0073] In some embodiments, the frequency, pulse width, and high level value of the pulses output by the pulse generator module 101 are controlled and adjusted by an automated test program running in the computer terminal device 151 to achieve the adjustment of the light emitting intensity of the monochromatic light emitting diodes. The period of the pulses output by the pulse generator module 101 is longer than the duration of the after-pulse probability of the single photon detector to be measured (usually within 5 ms) to eliminate the influence of the after-pulse of the single photon detector, but this limits the maximum applicable pulse frequency.

[0074] In some embodiments, the monochromatic light emitting diode array 103 comprises a plurality of monochromatic light emitting diodes (LEDs) with different wavelengths, and the array size and the emission wavelengths of the monochromatic light emitting diodes therein are selected according to the spectral range to be measured by the single photon detector. Different spatial positions in the monochromatic light emitting diode array correspond to different emission wavelengths of the monochromatic light emitting diodes, and the programmable switch selection circuit module 102 is controlled by the automated test program to selectively send the driving pulses input by the pulse generator 101 to a monochromatic light emitting diode with a certain wavelength in the monochromatic light emitting diode array, so as to realize the selection of the wavelength of the monochromatic light emitting diode. The programmable switch selection circuit module 102 in combination with the monochromatic light emitting diode array 103 realizes a monochromatic pulsed light source with adjustable wavelength in a wide spectral range.

[0075] In some embodiments, the pulse generator module 101 outputs two-way synchronized square-wave pulses of a specific frequency and pulse width, which can be 200 kHz and 20 ns, respectively, controlled by an automated test program running in the computer terminal device 151, one way is selectively sent to a monochromatic light-emitting diode (LED) of a certain wavelength in the monochromatic light-emitting diode (LED) array 103 via the monochromatic light-emitting diode (LED) programmable switch selection circuit module 102 for driving the monochromatic light-emitting diode (LED) to emit light pulses, and the other way is input to the start end of the event refresh time converter module 141, wherein the certain wavelength can be 670 nm.

[0076] The pulsed light emitted by the monochromatic light-emitting diode (LED) enters the integrating sphere through the entrance of the integrating sphere 111, and is homogenized in the integrating sphere and then exits from the horizontal and vertical openings, respectively. The light power exiting from the vertical opening of the integrating sphere 111 is monitored using the first calibrated photodiode 131 in combination with the power meter 132, while the light exiting from the horizontal opening directly irradiates the light-sensitive surface of the single-photon detector 121 under test, which is powered by the voltage source 122; the output of the single-photon detector 121 under test is connected to the end of the event refresh time converter module 141 to measure the time interval of the output pulse of the single-photon detector relative to the driving pulse of the monochromatic light-emitting diode (LED), and the corresponding measurement timing is shown in FIG. 2. The automated test program synchronously records the power measured by the power meter 132 and the time interval measured by the event refresh time converter module 141 within the set collection time.

[0077] When the data collection at a certain wavelength is completed, the automated test program running in the computer terminal device 151 controls the monochromatic light-emitting diode (LED) switch selection circuit module 102 to switch the driving pulse generated by the pulse generator module 101 to a monochromatic light-emitting diode (LED) of another wavelength, while the automated test program synchronously records the data measured by the power meter 132 and the event refresh time converter module 141 within the set collection time, and this process is repeated until all monochromatic light-emitting diodes (LEDs) of different wavelengths in the monochromatic light-emitting diode (LED) array 103 are measured.

[0078] In some embodiments, referring to FIG. 2, the timing of the single photon detector detection efficiency measurement based on the event refresh time converter is shown in FIG. 2, the driving pulse of the monochromatic light emitting diode (LED) and the start pulse of the event refresh time converter module 21, the light pulse emitted by the monochromatic light emitting diode (LED) 22, the pulse output by the single photon detector 23 as the end pulse of the event refresh time converter module, the time interval between the start pulse and the end pulse measured by the event refresh time converter 24, the event refresh time converter refers to the time interval between the start of the start pulse and the first event encountered by the end pulse, if the end of the event refresh time converter does not encounter an event within the maximum measurable time range, the measurement is forced to end and the next measurement is started.

[0079] Based on the above exemplary scenarios, referring to FIG. 3, the single photon detector detection efficiency measurement method of the present application includes, in one embodiment thereof:

[0080] Step S10, in response to the single photon detector detection efficiency measurement instruction, obtaining the light power of the first calibration photodiode and the second calibration photodiode irradiated by each monochromatic light emitting diode in the monochromatic light emitting diode array during the calibration measurement, to determine the calibration coefficient of each monochromatic light emitting diode;

[0081] The computer terminal device 151 in the single photon detector detection efficiency measurement system can respond to the single photon detector detection efficiency measurement instruction, obtain the light power of the first calibration photodiode 131 and the second calibration photodiode irradiated by each monochromatic light emitting diode in the monochromatic light emitting diode array 103 during the calibration measurement, to determine the calibration coefficient of each monochromatic light emitting diode, wherein the light sensitive area of the second calibration photodiode is at the same position as the light sensitive area of the single photon detector to be measured, the wavelengths of each monochromatic light emitting diode in the monochromatic light emitting diode array are different, the single photon detector to be measured includes a photomultiplier tube or a single photon avalanche diode, and the single photon avalanche diode includes a silicon (Si) single photon avalanche diode, an indium gallium arsenide (InGaAs) single photon avalanche diode, etc.

[0082] Further, referring to FIG. 4, the step of obtaining the light power of the first calibration photodiode and the second calibration photodiode irradiated by each monochromatic light emitting diode in the monochromatic light emitting diode array during the calibration measurement to determine the calibration coefficient of each monochromatic light emitting diode includes:

[0083] Step S101, determining the light power of the first calibration photodiode and the second calibration photodiode irradiated by each monochromatic light emitting diode in the monochromatic light emitting diode array during the calibration measurement;

[0084] Step S102, determining the scaling coefficient of each single-color light-emitting diode based on the ratio between the optical power of the second calibration photodiode and the optical power of the first calibration photodiode.

[0085] Specifically, to accurately obtain the average number of photons incident on the light-sensitive surface of the single-photon detector to be measured, it is necessary to perform a scaling measurement on the optical power at the positions of the reference detector (i.e., the first calibration photodiode 131) and the single-photon detector to be measured in FIG. 1. The first calibration photodiode 131 is kept unchanged, the single-photon detector to be measured is replaced by the second calibration photodiode, the light-sensitive surface of the single-photon detector to be measured is kept at the same position as the light-sensitive surface of the second calibration photodiode, and the optical powers of the first calibration photodiode 131 and the second calibration photodiode under the irradiation of each single-color light-emitting diode (LED) in the array of single-color light-emitting diodes (LEDs) are measured in turn to obtain the scaling coefficient of each single-color light-emitting diode (LED). The scaling coefficient of each single-color light-emitting diode (LED) is determined according to the ratio between the powers measured by the second calibration photodiode and the first calibration photodiode 131 during the scaling measurement.

[0086] The scaling coefficient of each single-color light-emitting diode (LED) is denoted as α calib The calculation formula is as follows:

[0087]

[0088] wherein α calib represents the scaling coefficient of each single-color light-emitting diode (LED), P PD2, calib (λ c ) is the power measured by the second calibration photodiode during the scaling measurement, and P PD1, calib (λ c ) is the power measured by the first calibration photodiode during the scaling measurement, and λ c is the center wavelength of each single-color light-emitting diode.

[0089] In some embodiments, the steps and procedures for performing calibration measurements on the optical power at the positions of the first calibration photodiode 131 and the single-photon detector to be measured, as shown in FIG1, are as follows: Keeping the first calibration photodiode 131 unchanged, the single-photon detector to be measured is replaced with a second calibration photodiode (not shown in FIG1). The photosensitive surfaces of the single-photon detector and the second calibration photodiode are kept at the same position. The automated test program in the computing terminal device controls the monochrome light-emitting diode (LED) switch selection circuit module 102, sequentially loading the driving pulses generated by the pulse generator module 101 onto each monochrome light-emitting diode (LED) in the monochrome light-emitting diode (LED) array according to the time sequence. During the illumination time of each monochrome light-emitting diode (LED), the automated test program synchronously records the optical power measured by the two calibration photodiodes, and further calculates the optical power according to the aforementioned calibration coefficient α. calib The calculation formula automatically calculates the scaling factor α for each monochrome light-emitting diode (LED). calib And store.

[0090] Step S20: Based on the calibration coefficient, the photosensitive area of ​​the single-photon detector to be measured, the photosensitive area of ​​the second calibration photodiode, and the optical power of the first calibration photodiode during the detection efficiency measurement of the single-photon detector to be measured, calculate and determine the average number of incident photons that each monochromatic light-emitting diode illuminates on the photosensitive area of ​​the single-photon detector to be measured.

[0091] After determining the calibration coefficient of each monochromatic light-emitting diode, the average number of incident photons illuminating the photosensitive area of ​​the single-photon detector to be measured is calculated based on the calibration coefficient, the photosensitive area of ​​the single-photon detector to be measured, the photosensitive area of ​​the second calibration photodiode, and the optical power of the first calibration photodiode during the detection efficiency measurement of the single-photon detector to be measured.

[0092] Further, referring to Figure 5, the step of calculating and determining the average number of incident photons illuminating the photosensitive area of ​​the single-photon detector under test by each monochromatic light-emitting diode during the detection efficiency measurement of the single-photon detector under test, based on the calibration coefficient, the photosensitive area of ​​the single-photon detector under test, the photosensitive area of ​​the second calibration photodiode, and the optical power of the first calibration photodiode during the detection efficiency measurement of the single-photon detector under test, includes:

[0093] Step S201: Obtain the photosensitive area of ​​the single-photon detector to be measured, the photosensitive area of ​​the second calibration photodiode, the calibration coefficient of each monochromatic light-emitting diode, the optical power of the first calibration photodiode during the detection efficiency measurement of the single-photon detector to be measured, the center wavelength emitted by each monochromatic light-emitting diode, and the frequency of the light pulse emitted by each monochromatic light-emitting diode.

[0094] Step S202: Calculate and determine a first ratio between the center wavelength emitted by each monochromatic light-emitting diode and the frequency of the light pulse emitted by each monochromatic light-emitting diode;

[0095] Step S203: Calculate and determine the second ratio between the photosensitive area of ​​the single-photon detector to be measured and the photosensitive area of ​​the second calibration photodiode;

[0096] Step S204: Calculate and determine the first product of the calibration coefficient of each monochromatic light-emitting diode and the optical power of the first calibrated photodiode during the measurement of the detection efficiency of the single-photon detector to be measured;

[0097] Step S205: Based on the first ratio, the second ratio, and the first product, calculate and determine the average number of incident photons that each monochromatic light-emitting diode illuminates on the photosensitive area of ​​the single-photon detector to be measured.

[0098] Specifically, the computer terminal device 151 in the single-photon detector detection efficiency measurement system acquires the photosensitive area of ​​the single-photon detector under test, the photosensitive area of ​​the second calibration photodiode, the calibration coefficient of each monochromatic light-emitting diode, the optical power of the first calibration photodiode during the detection efficiency measurement of the single-photon detector under test, the center wavelength emitted by each monochromatic light-emitting diode, and the frequency of the light pulse emitted by each monochromatic light-emitting diode, and determines Planck's constant and the speed of light in vacuum; firstly, it calculates and determines the first ratio between the center wavelength emitted by each monochromatic light-emitting diode and the frequency of the light pulse emitted by each monochromatic light-emitting diode. The process involves: calculating and determining a second ratio between the photosensitive area of ​​the single-photon detector to be measured and the photosensitive area of ​​the second calibration photodiode; calculating and determining a first product between the calibration coefficient of each monochromatic light-emitting diode and the optical power of the first calibration photodiode during the measurement of the detection efficiency of the single-photon detector to be measured; then calculating and determining the reciprocal of a second product between Planck's constant and the speed of light in vacuum; and using a third product based on the first ratio, the second ratio, the first product, and the reciprocal of the second product as the average number of incident photons irradiated onto the photosensitive area of ​​the single-photon detector to be measured by each monochromatic light-emitting diode.

[0099] More specifically, the calibration coefficient α obtained from the calibration measurement calib And the power P measured by the first calibration photodiode 131 during the detection efficiency measurement process. PD1, meas (λ c The average number of photons N illuminating the photosensitive surface of a single-photon detector. i (λ c The calculation formula for ) is expressed as follows:

[0100]

[0101] where h is Planck's constant, c is the speed of light in vacuum, f LED is the frequency of the light pulse emitted by each monochromatic LED (same as the frequency of the monochromatic LED driving pulse), A SPD is the light-sensitive area of the single-photon detector to be measured, A PD2 is the light-sensitive area of the second calibration photodiode, P PD1, meas (λ c ) represents the light power measured by the first calibration photodiode during the detection efficiency measurement of the single-photon detector to be measured, α calib is the scaling coefficient of each monochromatic LED.

[0102] Step S30, obtaining the time interval data generated by the single-photon detector to be measured in the event refresh time converter under the action of each light pulse at the same wavelength, and calculating the probability density of the time interval data falling into the preset statistical sub-interval of the statistical histogram to determine the time-domain photon probability distribution of the single-photon detector to be measured under the irradiation of each light pulse;

[0103] After determining the average number of incident photons of each monochromatic LED irradiated onto the light-sensitive area of the single-photon detector to be measured, the computer terminal device 151 in the single-photon detector detection efficiency measurement system obtains the time interval data generated by the single-photon detector to be measured in the event refresh time converter under the action of each light pulse at the same wavelength, and calculates the probability density of the time interval data falling into the preset statistical sub-interval of the statistical histogram to determine the time-domain photon probability distribution of the single-photon detector to be measured under the irradiation of each light pulse;

[0104] Further, referring to FIG. 6, the step of obtaining the time interval data generated by the single-photon detector to be measured in the event refresh time converter under the action of each light pulse at the same wavelength, and calculating the probability density of the time interval data falling into the preset statistical sub-interval of the statistical histogram to determine the time-domain photon probability distribution of the single-photon detector to be measured under the irradiation of each light pulse, includes:

[0105] Step S301, using the event refresh time converter to record the time interval data generated by the single-photon detector to be measured under the action of each light pulse;

[0106] Step S302, determining the width of each statistical sub-interval of the statistical histogram, wherein each statistical sub-interval represents a time interval range, and the width of the statistical sub-interval is greater than the width of the emission pulse of each monochromatic LED;

[0107] Step S303, distributing the time interval data generated by the to-be-measured single photon detector under the action of each light pulse to each statistical sub-interval to construct a statistical histogram;

[0108] Step S304, determining the total number of events in the statistical histogram and the count of the time interval range of each statistical sub-interval, and obtaining the probability density of the time interval range of each statistical sub-interval based on the ratio between the count of the time interval range of each statistical sub-interval and the total number of events in the statistical histogram, to determine the time-domain photon probability distribution of the to-be-measured single photon detector under the irradiation of each light pulse.

[0109] Specifically, after determining the average number of incident photons of each monochromatic light-emitting diode irradiated onto the photosensitive region of the to-be-measured single photon detector, the computer terminal device 151 in the single photon detector detection efficiency measurement system acquires the time interval data of the to-be-measured single photon detector generated under the action of each light pulse of the same wavelength in the event refresh time converter. The event refresh time converter can be used to record the time interval data of the to-be-measured single photon detector generated under the action of each light pulse. The width of each statistical sub-interval of the statistical histogram is determined, wherein each statistical sub-interval represents a time interval range, and the width of the statistical sub-interval is greater than the width of each monochromatic light-emitting diode emission pulse, which ensures that all possible time interval data can be captured without omission. The time interval data of the to-be-measured single photon detector recorded in step S301 is distributed to the predetermined statistical sub-intervals to construct a statistical histogram. The purpose of this step is to group and count the data for subsequent analysis and processing. The total number of events in the statistical histogram, i.e., the sum of all time interval data, is determined. Then, the time interval range of each statistical sub-interval is counted, and based on the ratio between the count of the time interval range of each statistical sub-interval and the total number of events, the probability density of the time interval range of each statistical sub-interval can be obtained. This step can determine the time-domain photon probability distribution of the to-be-measured single photon detector under the irradiation of each light pulse, i.e., describe the probability of photon emission in each time interval range.

[0110] Step S40, fitting the time-domain photon probability distribution with a preset photoelectron counting model to determine the average number of photoelectrons detected by the to-be-measured single photon detector under the action of a single light pulse;

[0111] determining the time-domain photon probability distribution p ph(j) thereafter, fitting the time-domain photon probability distribution measured by the time-to- digital converter module 141 using a preset photoelectron counting model to determine the average number of photoelectrons detected by the single-photon detector under the action of a single light pulse.

[0112] In some embodiments, the photoelectron counting model is:

[0113]

[0114] where j represents the jth statistical bin of the statistical histogram, y represents the probability that the single-photon detector does not detect a dark pulse within the time interval range of each statistical bin, z represents the probability that the single-photon detector does not detect both a photon-induced pulse and a dark pulse within the time interval range of each statistical bin, j dark represents the number of statistical bins contained in the delay time between the start pulse of the event- refreshed time-to-digital converter and the light pulse, m represents the mth photon probability peak in the statistical histogram, n represents the number of statistical bins contained between the photon probability peaks with a period of T p , and p ph (j) represents the time-domain photon probability distribution.

[0115] More specifically, j represents the jth statistical bin of the statistical histogram, which is a positive integer, and the time interval range (width) of each statistical bin (Bin) is Δt, so the time t can be represented as t = jΔt; y represents the probability that the single-photon detector does not detect a dark pulse within the time interval range of each statistical bin, where y = exp(-R dn Δt), which represents the probability that the single-photon detector does not detect a dark pulse within Δt time, R dn is the dark pulse count rate, which is given by the fitting; z represents the probability that the single-photon detector does not detect both a photon-induced pulse and a dark pulse within the time interval range of each statistical bin, where z = yexp(-μ), which represents the probability that the single-photon detector does not detect both a photon-induced pulse and a dark pulse within Δt time, and μ is the average number of photoelectrons detected by the single-photon detector under the action of a single light pulse; j dark represents the number of statistical bins contained in the delay time between the start pulse of the event- refreshed time-to-digital converter and the light pulse, where j dark = T delay / Δt, which represents the number of statistical bins (Bins) contained in the delay time between the start pulse of the event- refreshed time-to-digital converter and the light pulse, T delay represents the delay time between the start pulse of the event- refreshed time-to-digital converter and the light pulse, m represents the mth photon probability peak in the statistical histogram, and n represents the number of statistical bins contained between the photon probability peaks with a period of T pthe number of statistical bins (Bin) contained between the photon probability peaks; the exp( ) function is an exponential function used to calculate the base e of the natural logarithm.

[0116] In some embodiments, referring to FIG. 7, the time-domain probability distribution (solid line) measured by the event-averaged time-to-digital converter based on the single-photon avalanche diode single-photon detector under 670 nm LED pulsed light irradiation, and the probability distribution fitted by the above photoelectron counting model (dashed line); Dt is the width of the statistical bin (Bin), which is set to 500 ns, and the period is T p The probability peak represents the probability of detecting a light pulse, T delay represents the delay time between the start pulse of the event-averaged time-to-digital converter and the light pulse.

[0117] Step S50, determining the detection efficiency of the single-photon detector to be measured based on the average number of incident photons and the average number of photoelectrons, to complete the measurement of the detection efficiency of the single-photon detector.

[0118] After determining the average number of incident photons of each monochromatic light-emitting diode irradiated onto the photosensitive region of the single-photon detector to be measured and the average number of photoelectrons detected by the single-photon detector to be measured under the action of a single light pulse, the detection efficiency of the single-photon detector to be measured is determined based on the average number of incident photons and the average number of photoelectrons, to complete the measurement of the detection efficiency of the single-photon detector.

[0119] Further, referring to FIG. 8, the step of determining the detection efficiency of the single-photon detector to be measured based on the average number of incident photons and the average number of photoelectrons includes:

[0120] Step S501, determining the average number of incident photons of each monochromatic light-emitting diode irradiated onto the photosensitive region of the single-photon detector to be measured and the average number of photoelectrons detected by the single-photon detector to be measured under the action of a single light pulse;

[0121] Step S502, determining the detection efficiency of the single-photon detector to be measured based on the ratio between the average number of photoelectrons detected by the single-photon detector to be measured under the action of a single light pulse and the average number of incident photons of each monochromatic light-emitting diode irradiated onto the photosensitive region of the single-photon detector to be measured.

[0122] Specifically, the computer terminal device 151 in the single photon detector detection efficiency measurement system obtains the average number of incident photons of each monochromatic light emitting diode irradiated onto the photosensitive region of the single photon detector to be measured and the average number of photoelectrons detected by the single photon detector to be measured under the action of a single light pulse. The detection efficiency of the single photon detector to be measured is determined based on the ratio between the average number of photoelectrons detected by the single photon detector to be measured under the action of a single light pulse and the average number of incident photons of each monochromatic light emitting diode irradiated onto the photosensitive region of the single photon detector to be measured.

[0123] More specifically, the formula for calculating the detection efficiency of the single photon detector to be measured is as follows:

[0124]

[0125] wherein PDE(λ c ) represents the detection efficiency of the single photon detector to be measured, μ represents the average number of photoelectrons detected by the single photon detector under the action of a single light pulse, N i (λ c ) represents the average number of incident photons of each monochromatic light emitting diode irradiated onto the photosensitive region of the single photon detector to be measured.

[0126] According to the above embodiment, compared with the prior art, in order to obtain a true photon counting rate, the prior art single photon detector detection efficiency measurement method needs to correct the actual measured counting rate for dark counting, post-pulse and dead time. These additional measurements and corrections not only greatly increase the complexity of detection efficiency measurement, but also introduce additional measurement errors and other problems. The present application includes but is not limited to the following beneficial effects:

[0127] First, the event refresh time converter only measures the arrival time of the first event (i.e. the end pulse) after the start pulse, and the start and end pulses of the event refresh time converter are the synchronization pulse of the light source and the pulse output by the single photon detector, respectively. In this measurement mode, the dead time of the single photon detector does not affect the detection probability of the first event.

[0128] Second, the light pulse period is much larger than the duration of the post-pulse probability of the single photon detector, so as to ensure that the probability of a post-pulse event occurring within the duration of the light pulse is zero.

[0129] Third, the time domain probability distribution measured by the event refresh time converter is fitted using the established photoelectron counting model, so as to simultaneously obtain the average number of detected photoelectrons and the dark counting rate, without the need for prior measurement and correction of the dark counting effect of the single photon detector.

[0130] Further, the single-photon detector detection efficiency measurement method provided by the application can quickly and accurately measure the detection efficiency spectrum of the single-photon detector in a wide spectral range, without the need for additional measurement and correction of the dead time, dark count rate and after-pulse probability of the single-photon detector, greatly reducing the amount of data that needs to be directly measured, avoiding the introduction of additional measurement errors, greatly improving the measurement efficiency, and significantly improving the measurement accuracy of the detection efficiency spectrum.

[0131] Referring to FIG. 9, a single-photon detector detection efficiency measurement device provided for one of the purposes of the application includes a scaling factor determination module 1100, an incident photon number determination module 1200, a probability distribution determination module 1300, a photoelectron number determination module 1400, and a detection efficiency determination module 1500. The scaling factor determination module 1100 is configured to obtain the optical power of the first calibration photodiode and the second calibration photodiode under the irradiation of each monochromatic light-emitting diode in the monochromatic light-emitting diode array in the scaling measurement process in response to a single-photon detector detection efficiency measurement instruction, so as to determine the scaling factor of each monochromatic light-emitting diode. The incident photon number determination module 1200 is configured to calculate and determine the average incident photon number of each monochromatic light-emitting diode irradiated onto the photosensitive area of the single-photon detector to be measured according to the scaling factor, the photosensitive area of the single-photon detector to be measured, the photosensitive area of the second calibration photodiode, and the optical power of the first calibration photodiode in the detection efficiency measurement process of the single-photon detector to be measured. The probability distribution determination module 1300 is configured to obtain the time interval data generated by the single-photon detector to be measured under the action of each light pulse at the same wavelength in the time-to-digital converter during event refreshing, calculate and determine the probability density of the time interval data falling into a preset statistical sub-interval of a statistical histogram, so as to determine the time-domain photon probability distribution of the single-photon detector to be measured under the irradiation of each light pulse. The photoelectron number determination module 1400 is configured to fit the time-domain photon probability distribution by using a preset photoelectron counting model, so as to determine the average number of photoelectrons detected by the single-photon detector to be measured under the action of a single light pulse. The detection efficiency determination module 1500 is configured to determine the detection efficiency of the single-photon detector to be measured based on the average incident photon number and the average number of photoelectrons, so as to complete the measurement of the detection efficiency of the single-photon detector.

[0132] On the basis of any of the embodiments of the present application, referring to FIG. 10, another embodiment of the present application further provides an electronic device, which can be implemented by a computer device, as shown in FIG. 10, a schematic diagram of the internal structure of the computer device. The computer device comprises a processor, a computer readable storage medium, a memory and a network interface connected through a system bus. Among them, the computer readable storage medium of the computer device stores an operating system, a database and computer readable instructions, the database can store control information sequence, and the computer readable instructions can make the processor realize a single photon detector detection efficiency measurement method when executed by the processor. The processor of the computer device is used to provide computing and control capability to support the operation of the entire computer device. The memory of the computer device can store computer readable instructions, which can make the processor execute the single photon detector detection efficiency measurement method of the present application when executed by the processor. The network interface of the computer device is used to connect and communicate with the terminal. Those skilled in the art can understand that the structure shown in FIG. 10 is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different component arrangement.

[0133] The processor in the embodiment is used to execute the specific functions of each module and its sub-modules in FIG. 9, and the memory stores the program codes and various data required for executing the above-mentioned modules or sub-modules. The network interface is used for data transmission between the user terminal or the server. The memory in the embodiment stores the program codes and data required for executing all modules / sub-modules in the single photon detector detection efficiency measurement device of the present application, and the server can call the program codes and data of the server to execute the functions of all sub-modules.

[0134] The present application further provides a storage medium storing computer readable instructions, which, when executed by one or more processors, cause the one or more processors to perform the steps of the single photon detector detection efficiency measurement method described in any of the embodiments of the present application.

[0135] The present application further provides a computer program product comprising computer programs / instructions, which, when executed by one or more processors, implement the steps of the single photon detector detection efficiency measurement method described in any of the embodiments of the present application.

[0136] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments of the method of the present application can be completed by a computer program instructing relevant hardware, and the computer program can be stored in a computer readable storage medium. When the program is executed, it can include the processes of the above-mentioned embodiments of the method. The storage medium can be a computer readable storage medium such as a magnetic disc, an optical disc, a read-only memory (ROM), or a random access memory (RAM).

[0137] The above only describes some embodiments of the present application. It should be pointed out that those skilled in the art can make some improvements and refinements without departing from the principles of the present application. These improvements and refinements should also be considered as the protection scope of the present application.

[0138] In summary, the single photon detector detection efficiency measurement method provided by the present application can quickly and accurately measure the detection efficiency spectrum of the single photon detector in a wide spectral range. Without additional measurement and correction of the dead time, dark count rate and afterpulse probability of the single photon detector, the amount of data that needs to be directly measured is greatly reduced, additional measurement errors are avoided, the measurement efficiency is greatly improved, and the measurement accuracy of the detection efficiency spectrum is significantly improved.

Claims

1. [Rule 91 correction 11.07.2025] A method for measuring the detection efficiency of a single-photon detector, characterized in that, The method comprises the following steps: In response to the single-photon detector detection efficiency measurement instruction, the light powers of the first calibration photodiode and the second calibration photodiode under the irradiation of each monochromatic light-emitting diode in the monochromatic light-emitting diode array in the calibration measurement process are obtained to determine the calibration coefficient of each monochromatic light-emitting diode; According to the calibration coefficient, the light-sensitive area of the single-photon detector to be measured, the light-sensitive area of the second calibration photodiode, and the light power of the first calibration photodiode in the detection efficiency measurement process of the single-photon detector to be measured, the average number of incident photons of each monochromatic light-emitting diode irradiated onto the light-sensitive area of the single-photon detector to be measured is calculated and determined; The time interval data generated by the single-photon detector to be measured in the event refresh time converter under the action of each light pulse of the same wavelength is obtained, and the probability density of the time interval data falling into a preset statistical sub-interval of a statistical histogram is calculated and determined to determine the time-domain photon probability distribution of the single-photon detector to be measured under the irradiation of each light pulse; The time-domain photon probability distribution is fitted by using a preset photoelectron counting model to determine the average number of photoelectrons detected by the single-photon detector to be measured under the action of a single light pulse; The detection efficiency of the single-photon detector to be measured is determined based on the average number of incident photons and the average number of photoelectrons to complete the measurement of the detection efficiency of the single-photon detector.

2. [R91 amendment 11.07.2025] The method for measuring detection efficiency of a single photon detector according to claim 1, characterized in that, The step of obtaining the light powers of the first calibration photodiode and the second calibration photodiode under the irradiation of each monochromatic light-emitting diode in the monochromatic light-emitting diode array in the calibration measurement process to determine the calibration coefficient of each monochromatic light-emitting diode comprises the following steps: The light powers of the first calibration photodiode and the second calibration photodiode in the calibration measurement process are determined under the irradiation of each monochromatic light-emitting diode in the monochromatic light-emitting diode array; The calibration coefficient of each monochromatic light-emitting diode is determined based on the ratio between the light power of the second calibration photodiode and the light power of the first calibration photodiode.

3. [R91 amendment 11.07.2025] The method for measuring detection efficiency of a single photon detector according to claim 1, characterized in that, The step of calculating and determining the average number of incident photons of each monochromatic light-emitting diode irradiated onto the light-sensitive area of the single-photon detector to be measured according to the calibration coefficient, the light-sensitive area of the single-photon detector to be measured, the light-sensitive area of the second calibration photodiode, and the light power of the first calibration photodiode in the detection efficiency measurement process of the single-photon detector to be measured comprises the following steps: The light-sensitive area of the single-photon detector to be measured, the light-sensitive area of the second calibration photodiode, the calibration coefficient of each monochromatic light-emitting diode, the light power of the first calibration photodiode in the detection efficiency measurement process of the single-photon detector to be measured, the center wavelength of each monochromatic light-emitting diode, and the frequency of the light pulse emitted by each monochromatic light-emitting diode are obtained; A first ratio between the center wavelength of each monochromatic light-emitting diode and the frequency of the light pulse emitted by each monochromatic light-emitting diode is calculated and determined; A second ratio between the light-sensitive area of the single-photon detector to be measured and the light-sensitive area of the second calibration photodiode is calculated and determined; calculating a first product of the scaling factor of each monochromatic light-emitting diode and the light power of the first calibration photodiode in the detection efficiency measurement process of the single-photon detector to be measured; based on the first ratio, the second ratio and the first product, calculating a mean number of incident photons of each monochromatic light-emitting diode irradiated onto the light-sensitive region of the single-photon detector to be measured.

4. [R91 amendment 11.07.2025] The method for measuring detection efficiency of a single photon detector according to claim 1, characterized in that, The step of calculating the probability density of the time interval data of the single-photon detector to be measured in the event refresh time converter under the action of each light pulse at the same wavelength falling into a preset statistical sub-interval of a statistical histogram to determine the time-domain photon probability distribution of the single-photon detector to be measured under the irradiation of each light pulse, comprises: using the event refresh time converter to record the time interval data of the single-photon detector to be measured under the action of each light pulse; determining the width of each statistical sub-interval of the statistical histogram, wherein each statistical sub-interval represents a time interval range, and the width of the statistical sub-interval is greater than the width of the emission pulse of each monochromatic light-emitting diode; distributing the time interval data of the single-photon detector to be measured under the action of each light pulse into each statistical sub-interval to construct a statistical histogram; determining the total events in the statistical histogram and the count of the time interval range of each statistical sub-interval, and obtaining the probability density of the time interval range of each statistical sub-interval based on the ratio between the count of the time interval range of each statistical sub-interval and the total events in the statistical histogram, to determine the time-domain photon probability distribution of the single-photon detector to be measured under the irradiation of each light pulse.

5. [Amended according to Rule 91 on 11.07.2025] The method for measuring the detection efficiency of a single-photon detector according to claim 1, characterized in that, The photoelectron counting model is: ， where j represents the jth statistical sub-interval of the statistical histogram; y = exp(-R dn Δt) represents the probability that the single-photon detector does not detect a dark pulse within the time interval range of each statistical sub-interval, R dn represents the dark pulse count rate, and Δt represents the time interval range of each statistical sub-interval; z = y exp(-μ) represents the probability that the single-photon detector does not simultaneously detect a photon-induced pulse and a dark pulse within the time interval range of each statistical sub-interval, and μ represents the average number of photoelectrons detected by the single-photon detector under the action of a single optical pulse; j dark represents the number of statistical sub-intervals contained in the delay time between the start pulse of the event refresh time converter and the optical pulse; m represents the mth photon probability peak in the statistical histogram; n represents the number of statistical sub-intervals contained between the photon probability peaks with a period of T p ; and p ph (j) represents the time-domain photon probability distribution.

6. [R91 amendment 11.07.2025] The method for measuring detection efficiency of a single photon detector according to claim 1, characterized in that, The step of determining the detection efficiency of the single-photon detector to be measured based on the mean number of incident photons and the mean number of photoelectrons, comprises: determining the mean number of incident photons of each monochromatic light-emitting diode irradiated onto the light-sensitive region of the single-photon detector to be measured and the mean number of photoelectrons detected by the single-photon detector to be measured under the action of a single light pulse; determining the detection efficiency of the single-photon detector to be measured based on the ratio between the mean number of photoelectrons detected by the single-photon detector to be measured under the action of a single light pulse and the mean number of incident photons of each monochromatic light-emitting diode irradiated onto the light-sensitive region of the single-photon detector to be measured.

7. [Amended according to Rule 91 on 11.07.2025] The method for measuring the detection efficiency of a single-photon detector according to any one of claims 1 to 6, characterized in that, The light-sensitive region of the second calibration photodiode is at the same position as the light-sensitive region of the single-photon detector to be measured, the wavelengths of each monochromatic light-emitting diode in the array of monochromatic light-emitting diodes are different, and the single-photon detector to be measured comprises a photomultiplier tube or a single-photon avalanche diode.

8. [Amended according to Rule 91 on 11.07.2025] An apparatus for measuring the detection efficiency of a single-photon detector, characterized in that, comprises: a scaling factor determination module configured to, in response to a single-photon detector detection efficiency measurement instruction, obtain the light power of the first calibration photodiode and the second calibration photodiode under the irradiation of each monochromatic light-emitting diode in the array of monochromatic light-emitting diodes in a scaling measurement process, to determine the scaling factor of each monochromatic light-emitting diode; The incident photon number determination module is configured to determine the average incident photon number of each single-color light-emitting diode irradiated onto the photosensitive region of the single-photon detector to be measured according to the scaling coefficient, the photosensitive area of the single-photon detector to be measured, the photosensitive area of the second calibration photodiode, and the light power of the first calibration photodiode in the detection efficiency measurement process of the single-photon detector to be measured. The probability distribution determination module is configured to obtain time interval data of the single-photon detector to be measured generated under the action of each light pulse at the same wavelength in the event refresh time-to-digital converter, to calculate and determine the probability density of the time interval data falling into a preset statistical sub-interval of a statistical histogram, so as to determine the time-domain photon probability distribution of the single-photon detector to be measured under the irradiation of each light pulse. The photoelectron number determination module is configured to fit the time-domain photon probability distribution by using a preset photoelectron counting model, so as to determine the average number of photoelectrons detected by the single-photon detector to be measured under the action of a single light pulse. The detection efficiency determination module is configured to determine the detection efficiency of the single-photon detector to be measured based on the average incident photon number and the average number of photoelectrons, so as to complete the measurement of the detection efficiency of the single-photon detector.

9. [Amended according to Rule 91 on 11.07.2025] An electronic device comprising a central processing unit and a memory, characterized in that, The central processing unit is configured to call and run a computer program stored in the memory to execute the steps of the method according to any one of claims 1 to 7.

10. [R91 amendment 11.07.2025] A computer-readable storage medium, characterized in that, The computer program is stored in the form of computer readable instructions and is realized according to the method of any one of claims 1 to 7. When the computer program is called and run by a computer, the steps included in the corresponding method are executed.

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