X-ray machine tube voltage measuring device and method based on energy spectrum detector

Abstract

The invention discloses an X-ray machine tube voltage measuring device and method based on an energy spectrum detector. The measuring device comprises a filter, a collimator, the energy spectrum detector, a data acquisition module and an upper computer. During measurement, an energy spectrum detector is calibrated firstly, and the corresponding relation between a channel value and energy is established; then known tube voltage X-ray energy spectrum measurement is carried out, an energy spectrum curve of known tube voltage is obtained, and the energy spectrum curve is used for representing the corresponding relation between energy and counting; and then feature point and feature point energy determination and secondary calibration are carried out in sequence to obtain a corresponding relation between energy and tube voltage. During actual measurement, the X-ray energy spectrum data of the voltage of the to-be-measured tube is collected through the energy spectrum detector, an energy spectrum curve is obtained through processing and conversion, then the feature points and the energy of the feature points are obtained, and the tube voltage can be obtained reversely. According to the invention, the tube voltage can be accurately measured under different working conditions, and the problems of large tube voltage measurement error, complex calibration and high cost in the prior art are solved.

Description

Technical Field

[0001] This invention relates to X-ray phototube voltage measurement, specifically to an X-ray phototube voltage measurement device and method based on an energy spectrum detector, belonging to the technical field. Background Technology

[0002] X-ray machines are a type of medical imaging equipment, primarily used for disease diagnosis and treatment. Modern X-ray machines are divided into diagnostic machines and therapeutic machines: diagnostic machines use digital imaging technology to examine multiple areas such as bones, chest, and abdomen; therapeutic machines utilize ionization effects to inhibit the growth of abnormal cells. The core components of the equipment include the X-ray tube (cathode filament and anode target), a high-voltage generator, and a digital detector, and the radiation dose is controlled by adjusting the tube current and voltage.

[0003] X-ray tube voltage is one of the core factors affecting image quality in non-destructive testing imaging systems used in fields such as medical imaging, security inspection, industrial flaw detection, and scientific research. It is crucial for ensuring the performance and correct operation of instruments and equipment, and for guaranteeing the accuracy and reliability of non-destructive testing. Inaccurate tube voltage can lead to blurry images or insufficient contrast, affecting image quality and test results. Theoretically, the more accurate the X-ray tube voltage setting and the smaller the fluctuations, the clearer the image.

[0004] Currently, X-ray tube voltage measurement methods are mainly divided into two types: invasive and non-invasive. Invasive methods require direct connection to a high-voltage circuit. For example, the Chinese utility model patent with publication number "CN211741357U" and invention title "An X-ray Tube Voltage Testing Device" discloses such an invasive measurement scheme. Invasive methods may pose safety hazards and interfere with the normal operation of the equipment, and are difficult to implement in some complex equipment. Non-invasive methods mainly include the thick-plate filtering method and the energy dispersive spectroscopy method. The thick-plate filtering method is mainly used for system stability verification and cannot directly provide an accurate voltage value. The energy dispersive spectroscopy method indirectly evaluates the tube voltage by analyzing the energy distribution characteristics of X-rays. It has the advantages of being non-invasive, highly adaptable, and simple to operate. However, it is prone to pulse accumulation effects at high dose rates and has high requirements for energy resolution and calibration. Summary of the Invention

[0005] To address the aforementioned shortcomings of existing technologies, the present invention aims to provide an X-ray optomechanical tube voltage measurement device and method based on an energy spectrum detector. The present invention can ensure accurate measurement of tube voltage under different operating conditions, solving the problems of large tube voltage measurement errors, complex calibration, and high costs in existing technologies.

[0006] The technical solution of this invention is implemented as follows:

[0007] An X-ray optomechanical tube voltage measurement device based on an energy spectrum detector includes a filter, a collimator, an energy spectrum detector, a data acquisition module, and a host computer;

[0008] The filter is directed towards the light output direction of the X-ray optical machine to be measured, and is used to filter out low-energy X-rays in the X-rays emitted by the X-ray optical machine.

[0009] The collimator is located after the filter and is used to allow X-rays from a specific direction coming from the filter to pass through, thereby reducing scattered rays and lowering the count rate;

[0010] The energy spectrum detector is used to receive X-rays passing through the collimator and convert them into analog signals;

[0011] The data acquisition module is used to acquire the energy spectrum data transmitted from the energy spectrum detector in real time and transmit it to the host computer.

[0012] The host computer is used to process and analyze the energy spectrum data transmitted from the data acquisition module to obtain the X-ray tube voltage and display it in real time.

[0013] Furthermore, it also includes a movable slide table and a linear slide rail, the linear slide rail being horizontally arranged, the movable slide table being arranged on the linear slide rail and being able to move back and forth along the linear slide rail; the filter, collimator, energy spectrum detector, and data acquisition module are arranged on the movable slide table.

[0014] Furthermore, it also includes a shielding shell that covers the filter, collimator, energy spectrum detector, data acquisition module, moving slide, and linear slide rail. The shielding shell is used to allow X-rays emitted by the X-ray machine to be measured to enter while blocking other light rays from entering.

[0015] Furthermore, the data acquisition module integrates a high-speed ADC and a pulse amplitude analyzer, employing a high-speed ADC of ≥8 bits and a pulse amplitude analyzer with a maximum channel address of not less than 1024 channels.

[0016] Furthermore, the collimator adopts a two-stage collimation structure, consisting of a primary collimator and a secondary collimator arranged front to back, with the collimation holes of the two stages facing each other and being the same size.

[0017] This invention also provides a method for measuring X-ray phototube voltage based on an energy spectrum detector, wherein the aforementioned X-ray phototube voltage measuring device based on an energy spectrum detector is obtained in advance; the specific measurement steps are as follows:

[0018] 1) Energy spectrum detector calibration: The energy spectrum detector is calibrated and its linearity is tested using a standard radioactive source with known energy. By measuring the peak position of the full-energy peak of the standard radioactive source, the correspondence between the channel value and the energy obtained from the energy spectrum detector test is established.

[0019] 2) X-ray energy spectrum measurement with known tube voltage: Measure the X-ray energy spectrum of different known tube voltages to obtain the correspondence between channel value and count under the known tube voltage. Based on the correspondence between channel value and energy obtained in step 1), the energy spectrum curve of each known tube voltage is obtained by conversion. The energy spectrum curve is used to characterize the correspondence between energy and count.

[0020] 3) Determine the location of the energy spectrum characteristic point corresponding to each known tube voltage, and obtain the energy and standard tube voltage at each characteristic point location:

[0021] 4) Secondary calibration: Fit the energy and standard tube voltage at all feature point locations obtained in step 3) to establish the correspondence between the energy and tube voltage at the feature point locations;

[0022] 5) X-ray energy spectrum measurement of tube voltage under test: Turn on the X-ray machine under test, set an appropriate output tube current to make the X-ray machine work normally, place the X-ray machine tube voltage measurement device based on the energy spectrum detector at an appropriate position of the X-ray beam exit, make the center of the collimator collimation hole aligned with the beam exit, and ensure that the energy spectrum detector can receive enough X-rays. The energy spectrum detector collects X-ray energy spectrum data.

[0023] 6) Determine the X-ray energy spectrum curve of the tube voltage under test: Preprocess the energy spectrum data to obtain the correspondence between channel value and count, and based on the correspondence between channel value and energy obtained in step 1), convert to obtain the X-ray energy spectrum curve of the tube voltage under test that characterizes the correspondence between energy and count;

[0024] 7) Determining the energy at the feature point: Determine the location of the energy spectrum feature point in the X-ray energy spectrum curve of the tube voltage under test in step 6) using the same method as in step 3), and then obtain the energy at the feature point location;

[0025] 8) Calculate the tube voltage value: Based on the correspondence between the energy at the feature point location and the tube voltage established in step 4), and the energy at the feature point location obtained in step 7), calculate the actual tube voltage value of the X-ray machine.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] 1. This method is a non-invasive method, which can reduce interference with the normal operation of X-ray optical machines and can be used for online measurement.

[0028] 2. This invention can improve the accuracy of tube voltage measurement, simplify the operation process, and ensure accurate measurement of tube voltage under different operating conditions.

[0029] 3. The present invention has a simple structure, is easy to operate, and is easy to mass-produce.

[0030] The X-ray tube voltage measurement scheme provided by this invention features non-invasiveness, high precision, strong real-time performance, and anti-interference capabilities. It solves the problems of large errors, complex calibration, and high costs in existing technologies, and can achieve a measurement error of ≤±1%. This provides a more reliable technical means for the quality control of X-ray optical machine products, daily equipment maintenance, and applications in related fields. Attached Figure Description

[0031] Figure 1 - A schematic diagram of the structure of the X-ray optomechanical tube voltage measurement device based on an energy spectrum detector according to the present invention.

[0032] Figure 2 - The energy spectrum detector calibration curve obtained in the embodiments of the present invention.

[0033] Figure 3 -The known tube voltage X-ray energy spectrum measurement curve obtained in the embodiments of the present invention.

[0034] Figure 4 - The secondary calibration curve obtained in the embodiments of the present invention.

[0035] Figure 5 - X-ray energy spectrum measurement curve of the tube voltage under test obtained in the embodiment of the present invention. Detailed Implementation

[0036] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0037] This invention provides an X-ray optomechanical tube voltage measurement device based on an energy spectrum detector. See also... Figure 1 The device includes a filter 1, a collimator 2, an energy spectrum detector 3, a data acquisition module 4, a host computer, a moving slide 6, a linear slide rail 5, and a shielding shell 7.

[0038] Filter 1 is positioned in the direction of the X-ray output from the X-ray machine to be measured. It is used to filter out low-energy X-rays, reduce the count rate, and minimize interference with high-energy rays. It can be selected and replaced according to the different tube voltages being measured. It can be made of materials such as aluminum, iron, copper, and lead, with a thickness of 1-10mm.

[0039] Collimator 2 is located after filter 1 and employs a two-stage or higher collimation design. The collimation apertures of the two collimators face each other and are the same size. It is used to allow X-rays from a specific direction coming from the filter to pass through, thereby reducing scattered rays and lowering the count rate; ensuring that the signal does not accumulate. Heavy metals such as lead, copper, and tungsten can be used. The diameter of the collimation aperture is 0.1-5mm, and the thickness is 5-50mm.

[0040] The energy spectrum detector 3 is used to receive X-rays from the collimator 2 and convert them into analog signals; and to perform pre-amplification, filtering, shaping, etc. It can use energy spectrum detectors with good energy resolution such as high-purity germanium (HPGe), zinc cadmium telluride (CZT), cadmium telluride (CdTe), silicon drift detector (SDD), lanthanum bromide (LaBr3), sodium iodide (NaI(Tl)) and gadolinium gallium aluminum garnet (GAGG).

[0041] The data acquisition module 4 integrates a high-speed ADC and a pulse amplitude analyzer, which can acquire energy spectrum data in real time and upload it to the host computer.

[0042] The host computer is used to acquire, process, analyze, store, and display the energy spectrum information transmitted by the data acquisition module, and can display the X-ray tube voltage value obtained from the test calculation in real time.

[0043] The movable slide 6 is mounted on the linear slide rail 5 and is used to carry the filter 1, collimator 2, energy spectrum detector 3, data acquisition module 4, etc. By moving the movable slide 6 back and forth on the linear slide rail 5, the relevant components on the movable slide 6 can adjust their positions according to the light output of the X-ray optical machine under test, so as to better receive the output light, control the count rate, and reduce signal accumulation.

[0044] The linear guide rail 5 is horizontally positioned to support the movable slide table 6, enabling it to move linearly. In this embodiment, the maximum moving distance is no less than 0.5m.

[0045] The shielding enclosure 7 covers the filter, collimator, energy spectrum detector, data acquisition module, moving slide, and linear guide rail. The shielding enclosure 7 allows X-rays emitted from the X-ray machine under test to enter while blocking other light rays, reducing the influence of scattered radiation, ambient background, and natural light on the testing system. In practice, the shielding enclosure is a rectangular shell with six sides to completely enclose the internal components. A through-hole can be provided at the front of the shielding enclosure to allow X-rays to pass through. Alternatively, a through-hole can be omitted, and carbon fiber plates can be used instead. Except for the front face of the shielding enclosure, the other five faces are shielded with heavy metal materials such as stainless steel, lead, and tungsten to reduce scattered radiation. Regardless of the structure, the purpose is to achieve light shielding, but it does not block X-rays incident directly on the front of the shielding enclosure.

[0046] The testing steps of this invention include energy spectrum detector calibration, X-ray energy spectrum measurement of a known tube voltage, determination of energy spectrum feature point positions and secondary calibration, X-ray energy spectrum measurement of the tube voltage to be tested and energy spectrum data preprocessing, determination of energy at feature point positions, and calculation of tube voltage values. The specific steps are as follows:

[0047] 1) Energy Spectrum Detector Calibration: The energy spectrum detector is calibrated and its linearity tested using a standard radioactive source of known energy to determine the detector's energy spectrum response curve and ensure the accuracy of the measurement results. The standard radioactive source can be selected from various options. 57 Co、 109 Cd, 55 Fe 241 Am、 137 Cs、 22 Na, etc. To ensure calibration accuracy, the single-energy ray energies should be ≥5. By measuring the peak positions of the full-energy peaks of these standard radioactive sources, the correspondence between the channel values ​​obtained from the energy spectrum detector and the energies is established. The calibration function is as follows:

[0048] f1(x) = ax + b;

[0049] Where x is the channel value, a and b are function coefficients, and f1(x) is the energy.

[0050] 2) X-ray energy spectrum measurement with known tube voltage: Since the energy spectrum detector can only obtain the correspondence between channel values ​​and counts at different known tube voltages when measuring X-ray energy spectra with different known tube voltages, this invention performs the calibration in step 1) beforehand, i.e., obtaining the correspondence between channel values ​​and energy. This allows the correspondence between channel values ​​and counts to be converted into a correspondence between energy and counts. The correspondence between energy and counts is the energy spectrum curve for each known tube voltage. To ensure the subsequent fitting effect, ≥5 tube voltage values ​​should be measured.

[0051] 3) Determine the location of energy spectrum feature points: Obtain the energy and standard tube voltage at each feature point location. The location of energy spectrum feature points can be determined using methods such as characteristic peaks, energy spectrum endpoints, and characteristic values ​​(1%-50% of peak value). In this embodiment, the energy value at a count rate of 5% of the peak count near the energy spectrum endpoint is selected as the location of the energy spectrum feature point.

[0052] 4) Secondary calibration: Fit the energy and standard tube voltage at all feature point locations obtained in step 3) to establish the correspondence between the energy and tube voltage at the feature point locations. Since the degree of spectral broadening varies for each type of energy spectrum detector, secondary calibration is required based on the corresponding feature point values. The expression for the secondary calibration function is as follows:

[0053] f2(x) = cx + d;

[0054] In this function, x represents energy, c and d are function coefficients, and f2(x) represents tube voltage.

[0055] 5) X-ray energy spectrum measurement of the tube voltage under test: Turn on the X-ray machine, set an appropriate output tube current to ensure the machine is in normal working condition, and place the entire measurement setup at a suitable position at the X-ray beam exit, ensuring the collimator center aperture is aligned with the beam exit. Simultaneously, select appropriate collimator center apertures and filters to ensure the energy spectrum detector receives sufficient X-rays while avoiding excessive X-ray quantity that could cause signal buildup and damage to the detector. Begin acquiring X-ray energy spectrum data, maintaining a stable measurement environment and avoiding interference from external factors during data acquisition.

[0056] 6) Determine the X-ray energy spectrum curve of the tube voltage under test: Preprocess the acquired energy spectrum data to obtain the correspondence between channel value and count, and based on the correspondence between channel value and energy obtained in step 1), convert to obtain the X-ray energy spectrum curve of the tube voltage under test that characterizes the correspondence between energy and count; Energy spectrum data preprocessing refers to the processing of the acquired energy spectrum data such as correction, smoothing, background subtraction, filtering, and noise and interference elimination.

[0057] 7) Determine the energy at the characteristic point of the voltage of the tube under test: Determine the position of the characteristic point of the X-ray energy spectrum curve of the voltage of the tube under test in step 6) using the same method as step 3), and then obtain the energy at the characteristic point of the voltage of the tube under test.

[0058] 8) Calculate the tube voltage value: Based on the correspondence between the energy at the feature point location and the tube voltage established in step 4), and the energy at the feature point location obtained in step 7), the actual tube voltage value of the X-ray machine can be calculated.

[0059] The measuring device and method of the present invention will be further described below with reference to embodiments.

[0060] This embodiment targets an X-ray optical engine with a maximum tube voltage of 150kV. In this specific embodiment, the filter uses a 1mm thick aluminum sheet; two 10mm thick tungsten collimators with 1mm collimation apertures are used as the first and second stage collimators, respectively. The energy spectrum detector uses a gadolinium gallium aluminum garnet energy spectrum detector; the shielding shell uses 5mm thick tungsten material with an opening at the front; the data acquisition module integrates a high-speed ADC and a pulse amplitude analyzer, employing a 16-bit high-speed ADC and a 4096-channel multi-channel pulse amplitude analyzer.

[0061] The specific steps for measuring the X-ray phototube voltage based on the energy dispersive spectroscopy detector in this embodiment are as follows:

[0062] 1) Energy Spectrum Detector Calibration: Using 241 Am (59.54kev) 176 Lu (201.83keV, 306.68keV), 22 Na (511keV)137 Five monoenergetic rays from four radioactive isotopes of Cs (661.66 keV) were used to calibrate the GAGG energy spectrum detector, establishing the correspondence between the channel values ​​and energies obtained from the detector tests. Figure 2 The calibration curve of the energy spectrum detector obtained in this embodiment is shown below, with the horizontal axis representing the channel value and the vertical axis representing the energy. The corresponding calibration scale function is as follows:

[0063] f1(x) = 0.26x + 11.52;

[0064] 2) X-ray energy spectrum measurement at known tube voltages: The energy spectrum of X-ray optomechanical tubes at different tube voltages is measured using a GAGG energy spectrum detector measurement device to obtain the correspondence between channel values ​​and counts at known tube voltages. Based on the correspondence between channel values ​​and energy obtained in step 1), the energy spectrum curve for each known tube voltage is obtained through conversion. This energy spectrum curve is used to characterize the correspondence between energy and counts. In this example, the voltage range is 40kV-150kV, with a step size of 10kV, and a total of 12 sets of tube voltages are set. Figure 3 The X-ray energy spectrum curves obtained from the test of this embodiment under known tube voltages are shown. The horizontal axis represents energy, and the vertical axis represents the normalized count.

[0065] 3) Determine the locations of characteristic points in the energy spectrum, and then obtain the energy and standard tube voltage at each characteristic point location. In this example, the energy value at the point where the count rate near the end of the energy spectrum is 5% of the peak count is selected as the characteristic point location; in this example, 12 characteristic points are... Figure 3 The intersection of the horizontal dashed line with the right side of the 12 energy spectrum curves.

[0066] 4) Secondary calibration: Fit the energy and standard tube voltage at all feature point locations obtained in step 3) to establish the correspondence between the energy at the feature point locations and the standard tube voltage. Figure 4 The embodiments of the present invention are based on Figure 3 The quadratic calibration curves were obtained by fitting 12 feature points, where the x-axis of each point represents the energy corresponding to that feature point, and the y-axis represents the standard tube voltage corresponding to that feature point. The corresponding quadratic calibration function is as follows:

[0067] f2(x) = 1.23x + 18.83;

[0068] 5) X-ray energy spectrum measurement of the tube voltage under test: Turn on the X-ray machine, set the appropriate output tube current and detector position to ensure the X-ray machine is in normal working condition, place the entire testing instrument at an appropriate position for the X-ray beam exit, install the collimator and filter, and collect X-ray energy spectrum data. To better test and verify the tube voltage measurement effect of this invention, the embodiment sets up energy spectrum data corresponding to 11 sets of tube voltage values ​​(from 45kV to 145kV, in 10kV steps).

[0069] 6) Determine the X-ray energy spectrum curve of the tube voltage under test: Preprocess the energy spectrum data, including correction, smoothing, background subtraction, filtering, and noise and interference removal. Obtain the correspondence between channel values ​​and counts. Based on the correspondence between channel values ​​and energy obtained in step 1), convert the data to obtain the X-ray energy spectrum curve of the tube voltage under test that characterizes the correspondence between energy and counts, such as... Figure 5 As shown.

[0070] 7) Energy Determination at Feature Point Locations: Following the same method as step 3), determine the locations of the energy spectrum feature points in the X-ray energy spectrum curve of the tube under test (step 6), and then obtain the energy at each feature point location. In this example, the energy value at the point where the count rate near the end of the energy spectrum is 5% of the peak count is selected as the feature point location. This example uses 11 feature points. Figure 5 The intersection of the horizontal dashed line with the right side of the 11 energy spectrum curves.

[0071] 8) Calculate the tube voltage value: Based on the correspondence between energy and tube voltage at the feature point location established in step 4), calculate the actual tube voltage value of the X-ray machine.

[0072] The table below shows the tube voltage values ​​and corresponding deviation rates calculated under different nominal tube voltage values ​​according to the energy spectrum data in this embodiment. As can be seen from the table, the present invention can achieve a measurement error of ≤±1%, with a maximum error of only 0.88%, an optimal result error of 0, and an average error of 0.48%. Therefore, the present invention can improve the accuracy of tube voltage measurement and ensure accurate measurement of tube voltage under different operating conditions, providing a more reliable technical means for quality control of X-ray optical machines, routine equipment maintenance, and applications in related fields.

[0073]

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the applicant has described the present invention in detail with reference to preferred embodiments, those skilled in the art should understand that any modifications or equivalent substitutions to the technical solutions of the present invention without departing from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A voltage measurement device for X-ray photomechanical tubes based on an energy spectrum detector, characterized in that: Includes filters, collimators, energy spectrum detectors, data acquisition modules, and host computers; The filter is directed towards the light output direction of the X-ray optical machine to be measured, and is used to filter out low-energy X-rays in the X-rays emitted by the X-ray optical machine. The collimator is located after the filter and is used to allow X-rays from a specific direction coming from the filter to pass through, thereby reducing scattered rays and lowering the count rate; The energy spectrum detector is used to receive X-rays passing through the collimator and convert them into analog signals; The data acquisition module is used to acquire the energy spectrum data transmitted from the energy spectrum detector in real time and transmit it to the host computer. The host computer is used to process and analyze the energy spectrum data transmitted from the data acquisition module to obtain the X-ray tube voltage and display it in real time.

2. The X-ray optomechanical tube voltage measurement device based on an energy spectrum detector according to claim 1, characterized in that: It also includes a movable slide table and a linear slide rail, the linear slide rail being horizontally set, the movable slide table being set on the linear slide rail and being able to move back and forth along the linear slide rail; the filter, collimator, energy spectrum detector, and data acquisition module are set on the movable slide table.

3. The X-ray optomechanical tube voltage measurement device based on an energy spectrum detector according to claim 2, characterized in that: It also includes a shielding shell that covers the filter, collimator, energy spectrum detector, data acquisition module, moving slide, and linear slide rail. The shielding shell is used to allow the X-rays emitted by the X-ray machine to be measured to enter while blocking other light rays from entering.

4. The X-ray optomechanical tube voltage measurement device based on an energy spectrum detector according to claim 3, characterized in that: The data acquisition module integrates a high-speed ADC and a pulse amplitude analyzer, employing a high-speed ADC of ≥8 bits and a pulse amplitude analyzer with a maximum channel address of not less than 1024 channels.

5. The X-ray optomechanical tube voltage measurement device based on an energy spectrum detector according to claim 1, characterized in that: The collimator adopts a two-stage collimation structure, consisting of a primary collimator and a secondary collimator arranged front and rear. The collimation holes of the two-stage collimators face each other and are the same size.

6. A method for measuring the voltage of an X-ray optomechanical tube based on an energy spectrum detector, characterized in that: The X-ray optomechanical tube voltage measurement device based on an energy spectrum detector as described in any one of claims 1-5 is obtained in advance; the specific measurement steps are as follows: 1) Energy spectrum detector calibration: The energy spectrum detector is calibrated and its linearity is tested using a standard radioactive source with known energy. By measuring the peak position of the full-energy peak of the standard radioactive source, the correspondence between the channel value and the energy obtained from the energy spectrum detector test is established. 2) X-ray energy spectrum measurement with known tube voltage: Measure the X-ray energy spectrum of different known tube voltages to obtain the correspondence between channel value and count under the known tube voltage. Based on the correspondence between channel value and energy obtained in step 1), the energy spectrum curve of each known tube voltage is obtained by conversion. The energy spectrum curve is used to characterize the correspondence between energy and count. 3) Determine the location of the energy spectrum characteristic point corresponding to each known tube voltage, and obtain the energy and standard tube voltage at each characteristic point location: 4) Secondary calibration: Fit the energy and standard tube voltage at all feature point locations obtained in step 3) to establish the correspondence between the energy and tube voltage at the feature point locations; 5) X-ray energy spectrum measurement of tube voltage under test: Turn on the X-ray machine under test, set an appropriate output tube current to make the X-ray machine work normally, place the X-ray machine tube voltage measurement device based on the energy spectrum detector at an appropriate position of the X-ray beam exit, make the center of the collimator collimation hole aligned with the beam exit, and ensure that the energy spectrum detector can receive enough X-rays. The energy spectrum detector collects X-ray energy spectrum data. 6) Determine the X-ray energy spectrum curve of the tube voltage under test: Preprocess the energy spectrum data to obtain the correspondence between channel value and count, and based on the correspondence between channel value and energy obtained in step 1), convert to obtain the X-ray energy spectrum curve of the tube voltage under test that characterizes the correspondence between energy and count; 7) Determining the energy at the feature point: Determine the location of the energy spectrum feature point in the X-ray energy spectrum curve of the tube voltage under test in step 6) using the same method as in step 3), and then obtain the energy at the feature point location; 8) Calculate the tube voltage value: Based on the correspondence between the energy at the feature point location and the tube voltage established in step 4), and the energy at the feature point location obtained in step 7), calculate the actual tube voltage value of the X-ray machine.

7. The method for measuring X-ray optomechanical tube voltage based on an energy spectrum detector according to claim 6, characterized in that: In step 1), the monoenergetic ray energies corresponding to the standard radioactive source with known energy should be ≥5.

8. The method for measuring X-ray optomechanical tube voltage based on an energy spectrum detector according to claim 6, characterized in that: In step 3), the location of the energy spectrum feature point is determined by any one of the characteristic peak, energy spectrum endpoint, or eigenvalue method.

9. The method for measuring X-ray optomechanical tube voltage based on an energy spectrum detector according to claim 6, characterized in that: In step 2), there are ≥5 known tube voltage values.

10. The method for measuring X-ray optomechanical tube voltage based on an energy spectrum detector according to claim 6, characterized in that: In step 6), energy spectrum data preprocessing refers to the process of correcting, smoothing, background subtraction, filtering, and eliminating noise and interference from the collected energy spectrum data.

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