Comprehensive test system and method for single-photon avalanche photodiode array

Abstract

The invention provides a comprehensive test system and method for a single photon avalanche photodiode array, and the method comprises the steps: generating two uniform light spots with a set diameter through a uniform light spot generation device, taking one uniform light spot as a calibration light spot, carrying out the calibration of the diameter and power of the light spot, and outputting the other uniform light spot to a to-be-tested device; driving the to-be-measured device to move towards a set direction, so that the uniform light spot irradiates a target pixel in the to-be-measured device or the whole photosensitive surface; collecting a signal generated after the to-be-detected device is irradiated by the light spot; and acquiring the collected signals, extracting test data of each single pixel and full frame in the device to be tested, and analyzing corresponding performance. According to the invention, accurate measurement and performance analysis of core indexes such as detection efficiency, post-pulse probability, dark count, crosstalk between pixels and the like of the device can be realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of single-photon detectors, and particularly relates to a comprehensive test system and method for a single-photon avalanche photodiode array. Background Technique

[0002] The statements in this part only provide background technical information related to the present invention and do not necessarily constitute prior art.

[0003] In recent years, the development of single-photon detectors has driven the upgrading of related test methods and test instruments. However, the existing test schemes only focus on one aspect, such as the generation device of lasers, the preparation of picosecond pulse light sources, the design of test fixtures, optical and electronic designs, etc., and there is no systematic test device, test method and detection specification. At present, the test device for a single SPAD (Single Photon Avalanche Diode) is already very mature, but for the single-photon detector of the SPAD array, no commercially mature test device has been found yet.

[0004] On the other hand, the existing test schemes will also refer to the test experience and test specifications of focal plane detectors, and test the full-frame array of the device through a quasi-uniform light spot. The existing test schemes for focal plane detectors mainly target linear mode array devices, and their test devices are as Figure 1 shown, including a system control and analysis device, a signal generation device, a laser light source, an optical attenuation device, an irradiation optical device, an optical measurement device, and the device under test. The signal generation device and the laser light source provide variable laser signals, control the optical power through the optical attenuation device, and the irradiation optical device expands the attenuated light beam into the light spot required for testing. It should ensure the power stability of the light spot irradiated on the pixels of the device under test, and the stability of the optical power can be detected by the optical measurement device. When the light irradiates on the device under test, the generated digital or analog signals are collected by the system control and analysis device, and the core parameters and performance indicators of the device are analyzed. Since the sensitivity of focal plane detectors is generally relatively high and is easily affected by external space light sources, the entire device under test is placed in a darkroom environment to ensure the test accuracy. This test device evaluates the imaging uniformity and blind pixel rate of the device through a quasi-uniform light spot. The laser used is generally continuous light and the optical power cannot be accurately attenuated to the single-photon level, so the single-photon performance indicators of the pixels cannot be accurately tested. At the same time, the test method for the full-frame device cannot meet the tests of core indicators such as the response uniformity of a single pixel and the crosstalk between pixels. Since each pixel of the SPAD array needs to have the ability to respond to a single photon, directly using the test scheme of linear mode array devices to test the entire photosensitive surface through a non-uniform light spot cannot evaluate the single-pixel response ability, crosstalk between pixels and other indicators of the device.

[0005] In summary, for devices such as SPAD arrays with extremely high sensitivity, regarding core indicators such as the photosensitive uniformity of pixels, detection efficiency, sensitivity, and crosstalk between pixels, the existing technologies have problems such as the test methods being not direct enough, the inspection process being non - quantitative, and the test results being inaccurate. Summary of the Invention

[0006] To solve the above problems, the present invention proposes a comprehensive test system and method for a single - photon avalanche photodiode array, which can achieve precise measurement and performance analysis of core indicators such as the detection efficiency, after - pulse probability, dark count, and crosstalk between pixels of the device.

[0007] According to some embodiments, the present invention adopts the following technical solutions:

[0008] A comprehensive test system for a single - photon avalanche photodiode array, comprising:

[0009] A uniform light spot generating device, configured to generate two uniform light spots with a set diameter. One uniform light spot is used as a calibration light spot for calibrating the light spot diameter and power, and the other uniform light spot is output to the single - photon avalanche photodiode array to be tested;

[0010] A motion control mechanism, configured to carry the single - photon avalanche photodiode array to be tested and capable of driving the single - photon avalanche photodiode array to be tested to move in a set direction, so that the uniform light spot irradiates the target pixel or the entire photosensitive surface in the single - photon avalanche photodiode array to be tested;

[0011] A data acquisition module, configured to acquire the signals generated after the single - photon avalanche photodiode array to be tested is irradiated by the light spot;

[0012] A data analysis module, configured to obtain the acquired signals, extract the test data of each single pixel and the full - frame in the single - photon avalanche photodiode array to be tested, and analyze the corresponding performance.

[0013] As an alternative implementation, the diameter of the uniform light spot is adjustable and the number of photons is controllable.

[0014] As an alternative embodiment, the uniform light spot generating device includes a pulsed light source, an optical attenuator, a collimator, a light homogenizing structure, a diaphragm, a beam splitter, and a calibration device, which are connected in sequence. The pulsed light source is used to emit pulsed light with different repetition frequencies. The optical attenuator is used to attenuate the pulsed light to the single-photon level. The collimator is used to collimate and expand the attenuated pulsed light and output it to the light homogenizing structure. The light homogenizing structure is used to convert the light with a Gaussian intensity distribution into a flat-top light with a uniform intensity distribution. The diaphragm is used to limit the spot diameter of the flat-top light beam so that the spot diameter is suitable for the detection range of the single-photon avalanche photodiode array to be measured, and output the flat-top light beam to the beam splitter. The beam splitter is used to split the light with the limited spot diameter, and the calibration device is used to calibrate the calibrated light spot.

[0015] As a further aspect, the calibration device includes a CCD camera and an optical power meter. The CCD camera is used to calibrate the spot diameter of the calibrated light spot, and the optical power meter is used to calibrate the power of the calibrated light spot.

[0016] As an alternative embodiment, the motion control mechanism can move along the x, y, and / or z axes, and the moving distance is controllable.

[0017] It can be an electric three-axis stage, a three-axis motion module, etc.

[0018] As an alternative embodiment, the corresponding performance includes at least one of detection efficiency, dark count rate, crosstalk between pixels, and blind pixel rate.

[0019] As an alternative embodiment, the data analysis module is configured to store the collected data, extract corresponding parameters according to the scan data during the test, draw corresponding curves, and display the calculated performance indicators.

[0020] A comprehensive test method for a single-photon avalanche photodiode array includes the following steps:

[0021] Determine the set diameter of the uniform light spot according to the performance to be tested;

[0022] Generate two uniform light spots with the set diameter. One uniform light spot is used as the calibrated light spot for calibrating the spot diameter and power, and the other uniform light spot is used to output to the single-photon avalanche photodiode array to be measured;

[0023] Drive the single-photon avalanche photodiode array to be measured to move in a set direction so that the uniform light spot irradiates the target pixel or the entire photosensitive surface in the single-photon avalanche photodiode array to be measured;

[0024] Collect the signals generated by the single-photon avalanche photodiode array to be measured after being irradiated by the light spot;

[0025] Obtain the collected signal, extract the test data of each single pixel and the full frame in the single photon avalanche photodiode array to be measured, and analyze the corresponding performance.

[0026] As an alternative embodiment, the performance to be tested includes at least one of detection efficiency, dark count rate, crosstalk between pixels, and blind pixel rate.

[0027] As an alternative embodiment, when testing the uniformity of the detection efficiency of single pixels in a single photon avalanche photodiode array, control the diameter of the uniform light spot to be less than a set value, control the number of photons per pulse, and evaluate the average number of photons per pulse per unit area according to the pulse frequency and attenuation parameters;

[0028] Control the single photon avalanche photodiode array to be measured to move horizontally, irradiate the uniform light spot on the photosensitive surface of the single photon avalanche photodiode array to be measured, and record the response parameters within each diameter range;

[0029] According to the average number of photons per pulse and the dark count rate, analyze the count rate generated by pulsed light, and calculate the detection efficiency of the corresponding photosensitive surface;

[0030] Scan each point position of the entire pixel, calculate the detection efficiency of each point, and analyze the uniformity of the response of a single pixel through the detection efficiency at different positions of a single pixel.

[0031] As an alternative embodiment, when testing the crosstalk between pixels in a single photon avalanche photodiode array, collect and analyze the count rate generated when pulsed light irradiates the current pixel;

[0032] Control the movement of the single photon avalanche photodiode array to be measured so that the light irradiates the adjacent pixel, and collect and analyze the count rate generated by crosstalk to the current pixel when the adjacent pixel is exposed to light;

[0033] Calculate the crosstalk between adjacent pixels.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] Through the uniform light spot generating device, the present invention realizes the generation of a uniform light spot, and can realize the adjustment of its diameter size and the control of light intensity and photon number. Combined with the motion control mechanism, driving the device to be measured to move, it is possible to perform performance testing and calibration on single-point pixels on the SPAD array, and also extract parameters and evaluate the performance of the entire array for the full frame, realizing the performance analysis of the entire SPAD array from point to surface. And because of the ability to analyze individual pixel points, the requirement for the uniformity of the light spot can be appropriately reduced during the full-frame evaluation.

[0036] The present invention uses a uniform light spot to scan and test the entire device to be tested. Through data acquisition, automatic extraction, automatic analysis, and evaluation of the core indicators of the SPAD array device can be completed, and accurate tests of indicators such as the responsivity uniformity, detection efficiency, afterpulse probability, and crosstalk of individual pixels of the SPAD array device can be completed.

[0037] The present invention helps to implement the SPAD array testing method, finally form a detection specification, boost the iterative upgrade of large-area SPAD arrays, and provide necessary support for industry applications.

[0038] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following specific preferred embodiments are given, and in conjunction with the accompanying drawings, the detailed description is as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The specification drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0040] Figure 1 is a schematic structural diagram of an existing test device;

[0041] Figure 2 is a schematic structural diagram of the test system of the SPAD array of this embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] The present invention will be further described below in conjunction with the drawings and embodiments.

[0043] It should be noted that the following detailed descriptions are all illustrative and are intended to provide a further description of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0044] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0045] Embodiment 1

[0046] An integrated test system for a single-photon avalanche photodiode array (hereinafter simply referred to as the device to be tested or SPAD array), as Figure 2 shown, includes:

[0047] A uniform spot generating device is used to generate two uniform spots with a set diameter. One uniform spot is used as a calibration spot for calibrating the spot diameter and power, and the other uniform spot is output to the single photon avalanche photodiode array to be measured.

[0048] A motion control mechanism is used to carry the single photon avalanche photodiode array to be measured and can drive the single photon avalanche photodiode array to be measured to move in a set direction, so that the uniform spot irradiates the target pixel or the entire photosensitive surface in the single photon avalanche photodiode array to be measured.

[0049] A drive circuit and a collection device are used to collect the signals generated after the single photon avalanche photodiode array to be measured is irradiated by the spot.

[0050] A data automatic extraction and analysis device is used to obtain the collected signals, extract the test data of each single pixel and the full frame in the single photon avalanche photodiode array to be measured, and analyze the corresponding performance.

[0051] In this embodiment, the uniform spot generating device mainly includes a picosecond pulse light source, an optical attenuator, a collimator, a light homogenizing structure, a diaphragm, a beam splitter, a CCD camera and an optical power meter.

[0052] The picosecond pulse light source is used to emit pulsed light with different repetition frequencies and output it to the optical attenuator through a single-mode optical fiber.

[0053] The optical attenuator is used to attenuate the pulsed light to the single photon level.

[0054] The collimator is used to collimate and expand the attenuated pulsed light (Gaussian beam) and output it to the light homogenizing structure (Gaussian to flat-top structure).

[0055] The light homogenizing structure is used to convert the light with a Gaussian distribution of light intensity into a flat-top light with a uniform light intensity distribution.

[0056] The diaphragm is used to limit the spot diameter of the flat-top beam, make the spot diameter suitable for the detection range of the device to be measured, and output the flat-top beam to the beam splitter.

[0057] The beam splitter is used to split the light with the limited spot diameter. One beam of light is output to the CCD camera and the optical power meter for calibrating the spot diameter and power, and the other beam of light is output to the device to be measured, where the device to be measured is installed on the motion control mechanism.

[0058] The uniform spot generating device is mainly used to generate an adjustable diameter spot with uniform light intensity and controllable photon number, which can be used for single pixel scanning and full frame scanning respectively, covering a single pixel point and the entire photosensitive surface of the SPAD array.

[0059] In this embodiment, the motion control mechanism adopts a high-precision electric multi-axis stage control device. The electric XYZ-axis stage control method can be selected. In other embodiments, the XY electric control and Z-axis manual control methods can also be adopted.

[0060] The motion of each axis is controlled by the data automatic extraction and analysis device. The data automatic extraction and analysis device controls the corresponding moving axis of the electric multi-axis stage to generate displacement, thereby adjusting the moving direction and distance of the stage.

[0061] The motion control mechanism can move in three dimensions along the x, y, and z axes, and it is sufficient to carry the device under test. In other embodiments, it can also be other motion devices such as a three-dimensional motion module or a multi-dimensional robotic arm. Exhaustive listing is not carried out here.

[0062] Of course, in other embodiments, according to the requirements of the test performance, the motion control mechanism can also be replaced by a two-dimensional motion mechanism, which can move on a horizontal plane.

[0063] The drive circuit and the acquisition device. In this embodiment, they mainly complete the drive timing control, status detection, and data acquisition functions of the device under test, and can directly output digital signals to the data automatic extraction and analysis device.

[0064] Existing drive circuits and acquisition devices can be used, and no further elaboration will be made here.

[0065] Of course, a separate control circuit can also be designed to cooperate with the corresponding performance test process, perform corresponding timing control and data reading, and transmit digital signals to the data automatic extraction and analysis device through a data acquisition card.

[0066] For example, if it is necessary to test each pixel of the device under test in sequence according to the test process, the diameter of the light spot can be determined according to the test requirements, and then the irradiation order of the pixels can be determined. The drive circuit formulates the corresponding control timing and data reading order according to the order.

[0067] In this embodiment, the data automatic extraction and analysis device stores the parameter data of the device under test collected locally, extracts the acquisition information, and calculates the core parameter indicators, including the detection efficiency, dark count rate, crosstalk between pixels, and / or blind pixel rate of each pixel, etc. After the data acquisition is completed, the full-frame test data and indicators of the device under test from point to surface are extracted and calculated.

[0068] The above processes can all be implemented through software programs or scripts.

[0069] Through the above system, uniform light with adjustable spot diameter and controllable number of photons can be prepared. The SPAD array is installed on the motion control mechanism, and the movement of the device to be tested is controlled to achieve the vertical incidence of the spot on a single pixel or the entire photosensitive surface of the array, complete the data acquisition of all pixels of the entire array, and finally complete the performance analysis of the array through the data automatic extraction and analysis device.

[0070] In this embodiment, the collected data is saved in the form of a file locally.

[0071] Of course, in other embodiments, a memory can also be configured, and the collected data is transmitted to the memory for storage and backup.

[0072] In some embodiments, the data automatic extraction and analysis device can also be configured with a corresponding interface display system to display test results, calculated performance results, etc. The calculated performance results can be obtained by real-time extraction and plotting of corresponding curves and statistical charts based on the scan data during the SPAD array test, or the indicators of the device to be tested can be automatically extracted from the scan data.

[0073] In this embodiment, the uniform spot generating device can generate two types of large and small spots that are very uniform and have controllable photon numbers, covering the entire photosensitive surface and a single pixel of the large area array SPAD array respectively, and is suitable for pixel testing of the SPAD array device from point to surface; using the high-precision electric multi-axis stage control device, the displacements of the X, Y, and Z axes of the stage can be configured to control the position of the large area array SPAD array and test a single pixel or the entire photosensitive surface at a specified position.

[0074] It is also possible to store the collected data locally for all pixels of the device through the data automatic extraction and analysis device, extract the collected information, and calculate the core parameter indicators. At the same time, after the data acquisition is completed, a software script is run to automatically extract and calculate the full-frame test data and indicators of the SPAD array device from point to surface.

[0075] Compared with the existing test scheme that directly uses a linear mode array device and tests the entire photosensitive surface with non-uniform spots, it is impossible to evaluate indicators such as the single pixel response ability and crosstalk between pixels of the device, and it has a significant effect.

[0076] Embodiment 2

[0077] Based on the system provided in Embodiment 1, this embodiment provides a method for testing the uniformity of the pixel detection efficiency of a SPAD array. Taking a 128×128 array and a SPAD array device with a single pixel of 25um×25um as an example, the description includes the following steps:

[0078] 1) Adjust the spot diameter ≤ 5um using a diaphragm. Control the number of photons per pulse through a picosecond pulsed light source and an optical attenuator. According to the pulse frequency of the picosecond pulsed light source and the attenuation parameter of the optical attenuator, the average number of photons per pulse per unit area can be evaluated.

[0079] 2) Place the device under test on the displacement platform fixture of the high-precision electric multi-axis stage control device. Control the movement of the device under test in the XY-axis directions through the stage, irradiate the spot on the photosensitive surface of the detector, and within a range of 5um × 5um, collect the corresponding response parameters through the drive circuit and the acquisition device, and transmit the response parameters to the data automatic extraction and analysis device. According to the average number of photons per pulse μ and the dark count rate R dc , analyze the count rate R generated by the pulsed light l , and calculate the detection efficiency η of the corresponding photosensitive surface according to the formula i :

[0080]

[0081] 3) Scan each point position of the entire pixel by moving the stage and upload the acquisition information to calculate the detection efficiency η of each point i , and analyze the uniformity of the single-pixel response through the detection efficiency η at different positions of a single pixel i .

[0082] Example 3

[0083] Based on the system provided in Example 1, this example provides a crosstalk between pixels of a SPAD array, including the following steps:

[0084] 1) Collect and analyze the count rate R generated when the pulsed light irradiates the current pixel l ;

[0085] 2) Move the stage to make the light irradiate the adjacent pixel, and collect and analyze the count rate R generated by crosstalk to the current pixel when the adjacent pixel is photosensitive ct ;

[0086] 3) Calculate the crosstalk between adjacent pixels:

[0087] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0088] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processors of general-purpose computers, special-purpose computers, embedded processors, or other programmable data processing devices to generate a machine, such that the instructions executed by the processors of the computer or other programmable data processing devices generate means for implementing the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0089] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0090] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0091] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made by those skilled in the art without creative efforts within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. An integrated test system for a single-photon avalanche photodiode array, characterized in that Including: A uniform light spot generating device for generating two uniform light spots with a set diameter. One uniform light spot is used as a calibration light spot for calibrating the light spot diameter and power, and the other uniform light spot is output to the single-photon avalanche photodiode array to be measured; A motion control mechanism for carrying the single-photon avalanche photodiode array to be measured and capable of driving the single-photon avalanche photodiode array to be measured to move in a set direction, so that the uniform light spot irradiates the target pixel or the entire photosensitive surface in the single-photon avalanche photodiode array to be measured; A data acquisition module for acquiring the signals generated after the single-photon avalanche photodiode array to be measured is irradiated by the light spot; A data analysis module for obtaining the acquired signals, extracting the test data of each single pixel and the full frame in the single-photon avalanche photodiode array to be measured, and analyzing the corresponding performance.

2. The integrated test system for a single-photon avalanche photodiode array according to claim 1, characterized in that, The diameter of the uniform light spot is adjustable, and the number of photons is controllable.

3. The integrated test system for a single-photon avalanche photodiode array according to claim 1 or 2, characterized in that, The uniform light spot generating device includes a pulse light source, an optical attenuator, a collimator, a light homogenizing structure, a diaphragm, a beam splitter, and a calibration device connected in sequence. The pulse light source is used for emitting pulse light with different repetition frequencies. The optical attenuator is used for attenuating the pulse light to the single-photon level; the collimator is used for collimating and expanding the attenuated pulse light and outputting it to the light homogenizing structure; the light homogenizing structure is used for converting the light with a Gaussian distribution of light intensity into a flat-top light with a uniform light intensity distribution; the diaphragm is used for limiting the light spot diameter of the flat-top light beam so that the light spot diameter is suitable for the detection range of the single-photon avalanche photodiode array to be measured, and outputting the flat-top light beam to the beam splitter; the beam splitter is used for splitting the light with the limited light spot diameter, and the calibration device is used for calibrating the calibration light spot.

4. The integrated test system for a single-photon avalanche photodiode array according to claim 3, characterized in that, The calibration device includes a CCD camera and an optical power meter. The CCD camera is used for calibrating the light spot diameter of the calibration light spot, and the optical power meter is used for calibrating the power of the calibration light spot.

5. The integrated test system for a single-photon avalanche photodiode array according to claim 1, characterized in that, The motion control mechanism can move along the x, y, and / or z axes, and the moving distance is controllable.

6. The integrated test system for a single-photon avalanche photodiode array according to claim 1, characterized in that, The corresponding performance includes at least one of detection efficiency, dark count rate, crosstalk between pixels, and blind pixel rate.

7. The integrated test system for a single-photon avalanche photodiode array according to claim 1, characterized in that, The data analysis module is configured to store the acquired data, extract corresponding parameters according to the scanning data during the test, draw corresponding curves, and display the calculated performance indicators.

8. An integrated test method for a single-photon avalanche photodiode array, characterized in that Including the following steps: Determine the set diameter of the uniform light spot according to the performance to be tested; Generate two uniform light spots with a set diameter. One uniform light spot is used as a calibration light spot for calibrating the light spot diameter and power, and the other uniform light spot is output to the single-photon avalanche photodiode array to be measured; Drive the single-photon avalanche photodiode array to be measured to move in a set direction so that the uniform light spot irradiates the target pixel or the entire photosensitive surface in the single-photon avalanche photodiode array to be measured; Acquire the signals generated after the single-photon avalanche photodiode array to be measured is irradiated by the light spot; Obtain the acquired signals, extract the test data of each single pixel and the full frame in the single-photon avalanche photodiode array to be measured, and analyze the corresponding performance.

9. The comprehensive test method of a single-photon avalanche photodiode array according to claim 8, characterized in that, When testing the uniformity of the detection efficiency of a single pixel of a single-photon avalanche photodiode array, control the diameter of the uniform light spot to be less than the set value, and control the number of photons per pulse. According to the pulse frequency and attenuation parameters, evaluate the average number of photons per pulse per unit area; Control the single-photon avalanche photodiode array under test to move in the horizontal direction, irradiate the uniform light spot on the photosensitive surface of the single-photon avalanche photodiode array under test, and record the response parameters within each diameter range; Based on the average number of photons per pulse and the dark count rate, analyze the count rate generated by the pulsed light, and calculate the detection efficiency of the corresponding photosensitive surface; Scan each point position of the entire pixel, calculate the detection efficiency of each point, and analyze the uniformity of the single-pixel response through the detection efficiency at different positions of a single pixel.

10. The comprehensive test method for a single-photon avalanche photodiode array according to claim 8, characterized in that, When testing the crosstalk between pixels of a single-photon avalanche photodiode array, collect and analyze the count rate generated when the pulsed light irradiates the current pixel; Control the movement of the single-photon avalanche photodiode array under test to make the light irradiate the adjacent pixel, and collect and analyze the count rate generated by crosstalk to the current pixel when the adjacent pixel is photosensitive; Calculate the crosstalk between adjacent pixels.

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