High sensitivity detector with remote adjustable feature and its sensitivity calibration method

Abstract

The application provides a high-sensitivity detector with remote adjustable characteristics and a sensitivity calibration method thereof, measures plateau characteristic curves of each sub-detector, and accurately obtains changes of signal output of the sub-detector in the combined detector due to voltage division. The variable resistor is adjusted to a suitable resistance value to make the corresponding branch sub-detector in an optimal working voltage state, eliminates weakening effects of voltage division on the detector, the variable resistor is adjusted to a maximum value to make the sub-detector of the corresponding voltage division branch approximate to be disconnected, changes a working state of the combined detector, obtains a multivariate linear equation of mutual shielding effect parameters of the sub-detector, and thus the parameters can be accurately obtained, so that influences caused by voltage division of the detector and influences caused by mutual shielding effects of the sub-detector are decoupled, influences of voltage division offset and the shielding effect on the performance of the combined detector can be quantitatively determined, and thus the detection performance such as the sensitivity of the combined detector can be greatly improved.

Description

Technical Field

[0001] This invention relates to the field of radiation detector technology. Background Technology

[0002] Typically, radiation detectors are used outside the reactor to monitor reactor power in real time during reactor startup, power operation, shutdown, and design basis accident conditions. These detectors output real-time power level and power change rate signals for reactor protection, playing a crucial role in safe reactor operation. During initial startup and other similar conditions, the ambient radiation field is extremely weak, requiring significantly improved detector sensitivity for effective monitoring.

[0003] In the field of radiation detection, multiple detectors are often combined into arrays to construct combined detectors for measurement, thereby improving detection range and sensitivity. However, due to various factors such as radiation shielding and blocking effects between individual detectors, as well as voltage deviations caused by applying voltage to multiple detectors using parallel voltage divider branches, the sensitivity of a combined detector is not simply the sum of the individual detectors. To achieve a high level of sensitivity, the combined detector system needs to be calibrated and adjusted to minimize these influencing factors.

[0004] Patent document CN104820233A discloses a scintillator array structure and a neutron detector using the scintillator array structure. The document describes the structure and operating mode of the neutron detector, but does not explain the calibration method.

[0005] Patent document CN202210182456.9 discloses a calibration method and system for a photodetector array, which calibrates the performance of the photodetector array and obtains the response matrix of the sub-detectors. However, the object is a photodetector, and the calibration is performed by sunlight. There is no self-shielding effect or voltage division effect between the detectors.

[0006] As mentioned above, in existing technologies, the combined detector is treated as a whole, and the overall output of the entire detector is examined. The overall effect of multiple performance parameters of the combined detector is analyzed. However, the performance parameters of the individual sub-detectors in the detector array are not analyzed in detail, and the potential of the detector cannot be fully explored. Moreover, if the detector performance is found to be unsatisfactory after calibration, the detector needs to be redesigned, such as modifying the number of detectors, layout, and other parameters. This process is time-consuming, costly, and inefficient. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a high-sensitivity detector with remotely adjustable features and its sensitivity calibration method, which can eliminate the influence of voltage division and shielding effects on detector performance and obtain higher detection performance.

[0008] The first aspect of this invention provides a sensitivity calibration method for a high-sensitivity detector with remotely adjustable characteristics. The detector includes multiple sub-detectors, each sub-detector having a predetermined setting position, and each sub-detector's voltage divider branch is connected to a variable resistor.

[0009] The calibration method includes the following steps:

[0010] Step S1: With the resistance of the variable resistor at 0, in the radiation field, each sub-detector is individually set at its predetermined position. The plateau voltage range U(i,min)~U(i,max) of the plateau curve of each sub-detector is measured, as well as the signal value N(i,rec) corresponding to the optimal operating voltage U(i,rec) of each sub-detector. Here, i=1,2,3,…M, and M is the number of sub-detectors.

[0011] Step S2: Place all sub-detectors in their predetermined positions, apply voltage to the detectors, measure the operating voltage U(i,com) of each sub-detector, and adjust the detector voltage and the resistance value of the variable resistor so that the operating voltage U(i,com) of each sub-detector is the optimal operating voltage U(i,rec).

[0012] Step S3: In the radiation field, measure the sum of the output signals N0(com) of all sub-detectors of the detector. N0(com) satisfies the following relationship:

[0013] N0(com)=a1·N(1,com)+a2·N(2,com)+……+a M ·N(M,com)

[0014] =a1·S0(1)·N(1,rec)+a2·S0(2)·N(2,rec)+……+a M ·S0(M)·N(M,rec)

[0015] =a1·N(1,rec)+a2·N(2,rec)+……+a M ·N(M,rec)

[0016] in,

[0017] a i This indicates the effect of the mutual shielding effect between sub-detectors on the signal output of the sub-detectors.

[0018] S0(i) = N(i,com) / N(i,rec)×100%, representing the voltage state of each sub-detector. Here, since the operating voltage U(i,com) of each sub-detector is the optimal operating voltage U(i,rec), S0(i) = 1.

[0019] Step S4: By adjusting the variable resistor of the voltage divider branch of at least one of the M sub-detectors to its maximum value, the voltage of that at least one sub-detector is approximately disconnected, while maintaining the voltage connection of the other sub-detectors. This process is repeated M-1 times to obtain M-1 different detector states j, j = 1, 2, 3…M-1. In each detector state j, steps S2 and S3 are executed to measure the sum N of the output signals of all sub-detectors. j (com), based on the M-1 measurement results, a is calculated. i .

[0020] Preferably, in step S4, in (M-1) measurements, the sum N of the output signals of all sub-detectors is obtained each time. j (com),

[0021] N j (com) satisfies the following relation:

[0022] N j (com)=a1·N(1,com)+a2·N(2,com)+……+a M ·N(M,com)

[0023] =a1·S j (1)·N(1,rec)+a2·S j (2)·N(2,rec)+……+a M ·S j (M)·N(M,rec)

[0024] The obtained N0(com), N1(com), ... N j Combining the equations from (com), we obtain the following equation:

[0025]

[0026] Solving the equation, we get a i .

[0027] Preferably, the resistance value of the variable resistor is at least two orders of magnitude higher than the resistance value of the detector.

[0028] Preferably, in step S1, the plateau curve is normalized, with the voltage V applied to each sub-detector as the abscissa and the ratio N(i,V) / N(i,rec)×100% corresponding to the signal value N(i,rec) corresponding to the optimal operating voltage U(i,rec) of the sub-detector as the ordinate, to obtain the plateau curve of the percentage signal output of each sub-detector.

[0029] Preferably, in step S4, when the state of the detector is changed, the position of each sub-detector and the radiation field remain unchanged.

[0030] Preferably, using the obtained S0(i) and a i This improves the performance of the detector.

[0031] A second aspect of the present invention provides a high-sensitivity detector with remotely adjustable features, which is calibrated using the calibration method provided in the first aspect of the present invention.

[0032] According to the detector and calibration method of the present invention, by measuring the plateau characteristic curves of each sub-detector, the gain state of the sub-detectors caused by voltage division in the combined detector can be accurately obtained. By changing the state of the combined detector, a multivariate linear equation concerning the mutual shielding effect parameters of the sub-detectors can be obtained. Combined with the obtained gain state parameters caused by detector voltage division, the gain caused by mutual shielding effect on the sub-detectors can be accurately obtained, thereby decoupling the gain caused by detector voltage division and the gain caused by mutual shielding effect of sub-detectors. This allows for the quantitative determination of the impact of voltage division offset and shielding effect on the performance of the combined detector, thereby greatly improving the sensitivity and other performance characteristics of the combined detector.

[0033] In this invention, each sub-detector has a variable resistor connected in its voltage divider branch. The voltage divider of the sub-detector can be finely adjusted by adjusting the resistance value of the variable resistor. In particular, the adjustment of the resistance value of the variable resistor can be done remotely, without having to be done on-site at the detector. This makes the adjustment of the voltage divider of the sub-detector simple and easy, reduces the frequency of close-range operation of the detector and proximity to the radiation source, and improves the efficiency and safety of calibration.

[0034] In this invention, by adjusting the resistance value of the variable resistor, the voltage division of the corresponding branch detector is made to the optimal operating voltage, which can eliminate the influence of voltage division on the detector, improve the sensitivity and accuracy of detector calibration, reduce the amount of data to be processed during calibration, simplify data processing, and simplify detector calibration. Attached Figure Description

[0035] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly described below.

[0036] Figure 1 This is a schematic diagram of a detector located within a radiation field according to a specific embodiment of the present invention;

[0037] Figure 2 This is a schematic diagram of the voltage divider branches of each sub-detector in a specific embodiment of the present invention;

[0038] Figure 3 This is a flowchart illustrating a detector calibration method according to a specific embodiment of the present invention;

[0039] Figure 4 This is a flowchart illustrating the measurement sub-detector plateau characteristic curve of a specific embodiment of the present invention;

[0040] Figure 5 This is a schematic diagram of a sub-detector installed at a predetermined position in a specific embodiment of the present invention;

[0041] Figure 6 This is the plateau characteristic curve of a sub-detector in a specific embodiment of the present invention;

[0042] Figure 7 This is a normalized plateau curve according to a specific embodiment of the present invention. Detailed Implementation

[0043] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0044] Figure 1 This is a schematic diagram of a detector 100 located in a radiation field according to a specific embodiment of the present invention.

[0045] like Figure 1 As shown, detector 100 is a detector array (also called a combined detector) consisting of multiple sub-detectors 1. Each sub-detector 1 is mounted on a specially designed support frame 2 (which can also be called a "test fixture" 2 when testing the detector). During detection and testing, the spatial position of each sub-detector 1 is fixed.

[0046] Detector 100 is located in the radiation field 3 and detects radiation. In this embodiment, as an example, neutron source 4 generates radiation field 3, and detector 100 is a neutron detector.

[0047] The number of sub-detectors 1 in detector 100 can be determined based on factors such as measurement requirements. Figure 1 In the middle, detector 100 contains 10 sub-detectors 1.

[0048] In this embodiment, a variable resistor is connected in series on the voltage divider branch of each sub-detector 1 to adjust the voltage of the sub-detector 1.

[0049] Figure 2 This is a schematic diagram of the voltage divider branch 6 of each sub-detector 1 in a specific embodiment of the present invention.

[0050] like Figure 2 As shown, each voltage divider branch 6 of the sub-detectors 1 in the combined detector 100 is connected to a variable resistor 5. By adjusting the resistance value of the variable resistor 5, the voltage applied to the sub-detector 1 can be changed. Preferably, the maximum resistance value of the variable resistor 5 is not lower than the resistance value of each sub-detector 1. More preferably, the maximum resistance value of the variable resistor 5 is two orders of magnitude higher than the resistance value of the sub-detector. In this way, by adjusting the resistance value of the variable resistor 5, the voltage division of the sub-detector can be significantly changed. When the resistance value of the variable resistor 5 is adjusted to its maximum value, the voltage divider branch can be substantially disconnected.

[0051] The variable resistor 5 can be adjusted remotely. Therefore, the voltage division of the sub-detector 1 can be adjusted remotely by controlling the resistance value of each variable resistor 5. This reduces the frequency of close-range operation of the detector 100 and the proximity to the radiation field 3, making operation convenient and improving the safety and efficiency of the calibration process.

[0052] Before conducting formal measurements, detector 100 needs to be calibrated to ensure it is in optimal working condition. When measuring extremely weak radiation fields, detector 100 should have sufficiently high detection sensitivity; therefore, it is necessary to calibrate detector 100 to maximize its sensitivity.

[0053] Figure 3 This is a flowchart of a calibration method for a detector 100 according to a specific embodiment of the present invention.

[0054] like Figure 3 As shown, the calibration method of the detector 100 in this embodiment includes the following steps.

[0055] Step S1: Sequentially set each sub-detector 1 individually at its predetermined installation position on the test fixture 2. In the radiation field 3, measure the plateau characteristic curve of each sub-detector 1 individually to determine the plateau voltage range of the plateau curve of each sub-detector 1, as well as the signal value measured by each sub-detector 1 under the optimal operating voltage recommended by the detector manufacturer.

[0056] When measuring the plateau curve of each sub-detector 1, the resistance value of the variable resistor 5 of each sub-detector 1 is set to 0.

[0057] Step S2: Set all sub-detectors 1 at their predetermined installation positions on the test fixture 2 to form a combined detector 100 (detector array). Apply voltage to the combined detector 100 and measure the actual operating voltage of each sub-detector 1. If the operating voltage of the sub-detector 1 is not the optimal operating voltage, adjust the voltage of the combined detector 100 and adjust the resistance value of the adjustable variable resistor 5 to make the operating voltage of each sub-detector 1 the optimal operating voltage.

[0058] Step S3: In the radiation field 3, the total output signal of the combined detector 100 is measured. The output signal satisfies a certain relationship with the output signals of each sub-detector 1, the voltage deviation state parameter, and the mutual shielding effect parameter of the sub-detectors.

[0059] In step S4, the voltage of at least one sub-detector 1 is approximately disconnected by adjusting the resistance of the variable resistor 5 of the voltage divider branch 6 of at least one sub-detector 1 in the detector 100 to the maximum value, while maintaining the voltage connection of other sub-detectors 1, resulting in different detector states. In different detector states, steps S2 and S3 are executed to measure the total output signal of the combined detector 100 and the voltage deviation state parameters of each sub-detector 1.

[0060] This process is repeated multiple times to obtain multiple measurement results. Based on these multiple measurement results, parameters characterizing the mutual shielding effect of the sub-detectors are calculated.

[0061] The detector calibration method of this embodiment is described in detail below.

[0062] First, let's explain step S1.

[0063] Figure 4 This is a flowchart illustrating the characteristic curve of the measurement sub-detector 1 ping (approximately 1 square meter) according to a specific embodiment of the present invention.

[0064] As mentioned above, when measuring the plateau curve of each sub-detector 1, the resistance value of each variable resistor 5 is set to 0.

[0065] like Figure 4 As shown, step S1 specifically includes the following steps.

[0066] Step S11: Place a sub-detector 1 on the test fixture 2 at the predetermined setting position 21 of the sub-detector.

[0067] Figure 5 This is a schematic diagram of a sub-detector 1 installed at a predetermined setting position 21 in a specific embodiment of the present invention.

[0068] One sub-detector 1 is installed at a predetermined position 21 on the test fixture 2, and no sub-detectors are installed at the other positions of the test fixture 2. Assume that the number of sub-detectors is M, and the sub-detector 1 is numbered from 1 to M. Figure 5 In the test fixture 2, the sub-detector 1 is the second one from the top (i=2), and the power supply of the sub-detector 1 is connected to make the sub-detector 1 work. Then the shield of the neutron source 4 is removed, so that the sub-detector 1 is in the radiation field 3.

[0069] Step S12: Adjust the voltage V of the sub-detector 1 (i=2) and record the signal value N(i,V) output by the sub-detector 1 (i=2) under different voltages V, and plot the plateau characteristic curve of the signal value changing with the voltage V of the sub-detector 1 (i=2).

[0070] Figure 6 The image shows the plateau characteristic curve of sub-detector 1 in a specific embodiment of the present invention.

[0071] Figure 6 In the diagram, the horizontal axis represents the voltage V applied to sub-detector 1 (i=2), and the vertical axis represents the signal value N(i,V) measured by sub-detector 1 (i=2) under voltage V. Figure 5 In this context, the type of signal value N(i,V) is exemplified by the count rate cps (counts per second).

[0072] Figure 6 In the middle, the signal value under voltage U(i,min) is N(i,min), and the signal value under voltage U(i,max) is N(i,max). The changes are not significant, showing a slowly changing region. This region is called the "plateau region" of the sub-detector 1. U(i,min) is the minimum voltage value of the plateau region, and U(i,max) is the maximum voltage value of the plateau region.

[0073] Figure 6 In this context, U(i,rec) represents the optimal operating voltage for sub-detector 1 (i=2), which is usually the recommended operating voltage value provided by the detector manufacturer, but can also be determined by the detector user through measurement. The signal value at voltage U(i,rec) is N(i,rec).

[0074] Step S13, will Figure 6 The plateau curve in the middle is normalized.

[0075] Figure 7 This is a normalized plateau curve according to a specific embodiment of the present invention.

[0076] about Figure 6The plateau curve is obtained by dividing the signal value N(i,V) at each voltage V by the signal value N(i,rec) at the optimal operating voltage U(i,rec). Figure 7 The normalized plateau curve in the figure. That is, Figure 7 The vertical axis represents the ratio of the signal value N(i,V) at voltage V to the signal value N(i,rec) at the optimal operating voltage U(i,rec), which is N(i,V) / N(i,rec)×100%. Therefore, Figure 7 The normalized plateau curve is also called the percentage signal output plateau curve. Figure 7 In the diagram, when the operating voltage U(i,com) of sub-detector 1 is at its optimal operating voltage U(i,rec), the value on the ordinate is 100%. When the operating voltage U(i,com) of sub-detector 1 deviates from the optimal operating voltage U(i,rec), the value on the ordinate deviates from 100%. Therefore, Figure 7 The percentage signal output plateau curve characterizes the effect of the change in the operating voltage U(i,com) of sub-detector 1 relative to the optimal operating voltage on the signal value of sub-detector 1.

[0077] Step S14: Replace sub-detector 1 by placing another sub-detector 1 at a predetermined setting position 21 on the test fixture 2. Do not place sub-detectors 1 at other positions on the test fixture 2. Repeat steps S11 to S13 to obtain the plateau curve of the other sub-detector 1.

[0078] This process is repeated so that the sub-detector number i takes values ​​from 1 to M. Steps S11 to S13 are executed M times in total to obtain the plateau voltage range U(i,min) to U(i,max) of the plateau curves of all M sub-detectors 1, the signal value N(i,rec) at the optimal operating voltage U(i,rec) of each sub-detector, and the percentage signal output plateau curve of each sub-detector 1.

[0079] Step 2 is explained in detail below.

[0080] As described above, in step S2, all sub-detectors 1 are set at their predetermined positions 21 on the test fixture 2 to form a combined detector 100 (detector array). A voltage is applied to the combined detector 100, and the actual operating voltage U(i,com) of each sub-detector 1 is measured using a voltage testing device. If the actual operating voltage U(i,com) of the sub-detector 1 is not the optimal operating voltage U(i,rec), the voltage of the combined detector 100 is adjusted, and the resistance value of the variable resistor 5 is adjusted (increasing the resistance value of the variable resistor 5 reduces the voltage division of the series-connected sub-detectors 1, decreasing the resistance value of the variable resistor 5 increases the voltage division of the series-connected sub-detectors 1) so that the operating voltage U(i,com) of each sub-detector 1 is its optimal operating voltage U(i,rec), and the operating voltage U(i,com) of all sub-detectors 1 at this time is recorded, i = 1, 2, 3...M.

[0081] Step 3 is explained in detail below.

[0082] In step S3, the radiation field 3 of the neutron source 4 is measured using the combined detector 100, and the total output signal NO(com) of the combined detector 100 is recorded. The total output signal NO(com) of the combined detector 100 is related to step S1 and the data obtained from step S1. Figure 5 The output signals N(1,com), ..., N(i,com), ..., N(M,com) of each individual sub-detector 1 under the voltage U(i,com) determined by the plateau curve satisfy the following relationship.

[0083]

[0084] In equation (1),

[0085] a i This describes the impact of the mutual shielding effect between sub-detectors 1 on the signal output of sub-detector 1. In the combined detector 100, other sub-detectors B exist around one sub-detector A. The surrounding sub-detectors B interact with neutrons, thus altering the neutron radiation field measured by sub-detector A. The mutual shielding effect (or self-shielding effect) of the sub-detectors is an interference factor that degrades the performance of detector 100. To improve detector sensitivity, it is necessary to determine the quantitative value of the sub-detector shielding effect to provide a basis for reducing the shielding effect.

[0086] S0(i) = N(i,com) / N(i,rec)×100%, representing the voltage state of each sub-detector. Here, since the operating voltage U(i,com) of each sub-detector is the optimal operating voltage U(i,rec), S0(i) = 1.

[0087] As shown in equation (1), the total output signal N0(com) of the combined detector 100 is not the sum of the individual output signals N(1,rec), ..., N(i,rec), ..., N(M,rec) of each sub-detector 1, but is affected by the mutual shielding effect between the sub-detectors 1 on the signal output of the sub-detectors 1, using parameter a i This indicates the impact.

[0088] In equation (1), a i S0(i)·N(i,rec) is the signal value N(i,rec) of the i-th sub-detector 1 at the optimal operating voltage U(i,rec) multiplied by the mutual shielding effect parameter a of the sub-detectors 1. i Then multiply by the voltage state parameter S0(i) of sub-detector 1 to obtain the contribution of the output signal of sub-detector 1 to the total output signal of the combined detector 100. The output signals a of all sub-detectors 1 are then multiplied. i S0(i) and N(i,rec) are added together to obtain the sum of the output signals of all sub-detectors 1 in detector state 0, N0(com), which is the total output signal of the combined detector 100.

[0089] In equation (1), only parameter a i Unknown, all other coefficients are known.

[0090] Step 4 is explained in detail below.

[0091] In step S4, without changing the installation position of each sub-detector 1, the position of the neutron source 4, and the state of the radiation field 3, the resistance value of the variable resistor 5 of the voltage divider branch 6 of at least one of the M sub-detectors 1 is adjusted to the maximum value, approximately disconnecting the voltage of the at least one sub-detector 1, while maintaining the voltage connection of the other sub-detectors 1, so that the state of detector 100 is different from detector state 0, which is recorded as detector state 1.

[0092] In detector state 1, step S2 is executed again, and the voltage of the detector is adjusted and the resistance value of the variable resistor 5 is adjusted so that the operating voltage U(i,com) of each sub-detector 1 maintaining the voltage connection is maintained at the optimal operating voltage U(i,rec). Then, step S3 is executed again, and the total output signal N1(com) of the group and detector 100 in detector state 1 is measured. N1(com) satisfies the following relationship:

[0093] N1(com)=a1·N(1,com)+a2·N(2,com)+……+a M ·N(M,com)

[0094] =a1·S1(1)·N(1,rec)+a2·S1(2)·N(2,rec)+……+a M ·S1(M)·N(M,rec) (2)

[0095] In equation (2),

[0096] a i This indicates the effect of the mutual shielding effect between sub-detectors 1 on the signal output of sub-detector 1. Since the installation position of sub-detector 1 and the state of the radiation field 3 remain unchanged, therefore a i Nothing changes.

[0097] S1(1)~S1(M) are the voltage states of each sub-detector 1 in detector state 1. For sub-detector 1 with the voltage divider being the optimal operating voltage U(i,rec), its S1(i) value is 1; for sub-detector 1 with the voltage divider branch 6 approximately open, its S1(i) value is 0.

[0098] The variable resistor in the voltage divider branch of at least one of the M sub-detectors is adjusted to its maximum value, approximately disconnecting the voltage of that at least one sub-detector, while maintaining the voltage connection of the other sub-detectors. This process is repeated M-1 times to obtain M-1 different detector states j, j = 1, 2, 3…M-1. In each detector state j, steps S2 and S3 are executed to measure the sum N of the output signals of all sub-detectors. j (com).

[0099] In each detector state j, steps S2 and S3 are executed to measure the voltage state S of each sub-detector 1. j (i), j = 1, 2, 3…M-1, and the total output signal N of detector 100 j (com), N j (com) satisfies the following relation:

[0100] N j (com)=a1·N(1,com)+a2·N(2,com)+……+a M ·N(M,com)

[0101] =a1·S j (1)·N(1,rec)+a2·S j (2)·N(2,rec)+……+a M ·S j (M)·N(M,rec) (3)

[0102] S j (1)~S j(M) represents the voltage state of each sub-detector 1 under detector state j. For sub-detector 1 with the optimal operating voltage U(i,rec) divided by voltage division, its S j (1) The value is 1; for the sub-detector 1 with the voltage divider branch 6 approximately open, its S j (M) value is 0.

[0103] This process is repeated M-1 times, resulting in M-1 relational expressions (3). Combining these with expression (1), there are a total of M relations. Since S... j Given (i) and N(i,rec), we can obtain the M a's based on these M relations. i The value of is used to obtain the shielding effect parameter 'a' for each sub-detector 1. i The value of is the effect of the mutual shielding effect on the signal output of sub-detector 1. Specifically, it is as follows.

[0104] The obtained equations (1), (2), (3), etc., have M N0(com), N1(com), ..., N j Combining the relational expressions, we obtain the following equation:

[0105]

[0106] Equation (4) is a system of M linear equations. Solving equation (4) yields a. i .

[0107] As described above, through steps S2 to S4, the influence of the voltage state of sub-detector 1 on the output signal of each sub-detector 1, S0(i), and the influence of the mutual shielding effect between sub-detectors 1 on the output signal of each sub-detector 1, a, can be obtained. i This enables precise calibration.

[0108] Using the obtained S0(i) and a i This can correct the output signal of detector 100, improve the detector's sensitivity and other detection performance, and allow for improvements to the detector design in subsequent designs based on the measurement results.

[0109] The present invention also provides a detector 100 for measuring radiation, which is calibrated using the above-described calibration method, and can achieve high sensitivity and good detection performance.

[0110] In the calibration method of this invention, the plateau characteristic curves of each sub-detector 1 are measured to accurately obtain the change in signal output of sub-detector 1 due to voltage division in the combined detector 100. The variable resistor 5 is adjusted to a suitable value to bring the corresponding branch sub-detector to the optimal operating voltage U(i,rec), eliminating the influence of voltage division on detector 100. The variable resistor 5 is then adjusted to its maximum value to make the sub-detector 1 of the corresponding voltage division branch 6 approximately disconnected, changing the operating state of the combined detector 100 and obtaining the mutual shielding effect parameter α of the sub-detectors 1. i The multivariate linear equation can be used to accurately obtain the parameter a. i This decouples the effects of voltage division by detector 100 from the mutual shielding effects of sub-detectors 1, enabling quantitative determination of the impact of voltage division offset and shielding effects on the performance of the combined detector 100, thereby significantly improving the detection performance, such as sensitivity, of the combined detector 1. Simultaneously, it allows for the acquisition of the characteristics of each sub-detector 1, providing a more comprehensive understanding of its operational status.

[0111] In this invention, each sub-detector 1 has a voltage divider branch connected to a variable resistor 5, which allows for remote real-time adjustment of the voltage division of the sub-detector 1. This provides a simple and easy method for creating different detector operating conditions during calibration, improving calibration efficiency and safety. Adjusting the variable resistor 5 to its maximum value makes the corresponding sub-detector 1 in the voltage divider branch 6 approximately disconnected, creating distinctly different operating conditions for the detector 100. This helps to expand the range and differences of data, reduce the influence of random errors, and improve calibration accuracy.

[0112] In this invention, by adjusting the resistance value of the variable resistor, the voltage division of the corresponding branch detector is made to the optimal operating voltage, which can eliminate the influence of voltage division on the detector, improve the sensitivity and accuracy of detector calibration, reduce the amount of data to be processed during calibration, simplify data processing, and simplify detector calibration.

[0113] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A sensitivity calibration method for a high-sensitivity detector with remote adjustable characteristics, wherein the detector comprises multiple sub-detectors, each sub-detector has a predetermined setting position, and a variable resistor is connected to the voltage divider branch of each sub-detector. The method is characterized by including the following steps: Step S1: With the variable resistor at 0 resistance, in the radiation field, each sub-detector is individually set at its predetermined position, and the plateau voltage range of the plateau curve of each sub-detector is measured. And the optimal operating voltage for each sub-detector. Corresponding signal value ,here i =1,2,3,…M, where M is the number of sub-detectors; Step S2: Place all the sub-detectors in their predetermined positions, apply voltage to the detectors, and measure the operating voltage of each sub-detector. And adjust the voltage of the detector and the resistance value of the variable resistor to adjust the operating voltage of each sub-detector. For optimal operating voltage ; Step S3: In the radiation field, measure the sum of the output signals of all sub-detectors of the detector. , The following relationship must be satisfied: in, This indicates the effect of the mutual shielding effect between sub-detectors on the signal output of the sub-detectors. = This indicates the voltage state of each sub-detector. Here, because the operating voltage of each sub-detector... For optimal operating voltage ,so =1; Step S4 involves approximately disconnecting the voltage of at least one sub-detector by adjusting the variable resistor of the voltage divider branch of at least one of the M sub-detectors to its maximum value, while maintaining the voltage connection of the other sub-detectors. This process is repeated M-1 times to obtain M-1 different detector states j. In each detector state j, steps S2 and S3 are performed to measure the sum of the output signals of all sub-detectors. Based on the M-1 measurement results, and the results in step S3 Calculations yielded ; In step S4, when the state of the detector is changed, the positions of each sub-detector and the radiation field remain unchanged.

2. The sensitivity calibration method for a high-sensitivity detector with remotely adjustable characteristics according to claim 1, characterized in that, In step S4, In (M-1) measurements, the sum of the output signals of all sub-detectors is obtained each time. , The following relationship must be satisfied: Get , , ... Combining these equations, we obtain the following equation: Solving the equation, we get .

3. The sensitivity calibration method for a high-sensitivity detector with remotely adjustable characteristics according to claim 1, characterized in that, The resistance value of the variable resistor is at least two orders of magnitude higher than the resistance value of the detector.

4. The sensitivity calibration method for a high-sensitivity detector with remotely adjustable characteristics according to claim 1, characterized in that, In step S1, the plateau curve is normalized, with the voltage V applied to each sub-detector as the abscissa and the signal value corresponding to voltage V as the ordinate. With the optimal operating voltage of this sub-detector Corresponding signal value ratio Using the vertical axis as the ordinate, we obtain the plateau curve representing the percentage signal output of each sub-detector.

5. The sensitivity calibration method for a high-sensitivity detector with remotely adjustable characteristics according to claim 1 or 2, characterized in that, Utilize This improves the performance of the detector.

6. A high-sensitivity detector with remotely adjustable features, calibrated using the calibration method of any one of claims 1 to 5.

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