Device and method for calibrating working characteristics of X-ray imaging sensor

Abstract

The invention discloses a device and a method for calibrating the working characteristics of an X-ray imaging sensor. The device comprises a high and low temperature test box, an X-ray imaging sensor module, an X-ray generator, a bracket, a power supply and a current acquisition module, the method comprises the following steps: S1, measuring the transmittance of a glass window of a high and low temperature test box; s2, recording the output current of the X-ray imaging sensor module at different temperatures and different X-ray intensities; s3, compensating the attenuation of the glass window to the X-ray intensity based on the transmittance in the S1; and S4, processing the obtained data, and calculating to obtain a function relationship among the output current of the X-ray imaging sensor, the X-ray intensity and the temperature so as to calibrate the working characteristics of the X-ray imaging sensor module. According to the invention, the size and price of the X-ray imaging equipment can be effectively reduced while the imaging quality and accuracy are ensured, and the development of the portable X-ray imaging equipment is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of X-ray imaging, and in particular to a device and method for calibrating the working characteristics of an X-ray imaging sensor. Background Art

[0002] X-rays are electromagnetic waves with extremely short wavelengths (0.01-10 nm) and extremely high energy (100 eV-10 MeV). They have strong penetrability and have been widely used in the fields of medical treatment, industrial nondestructive testing, security, etc. X-ray imaging equipment is mainly composed of X-ray generators, flat-panel detectors, image processing systems, and display devices. Flat-panel detectors are key components of X-ray imaging equipment, and X-ray imaging sensors based on thin-film transistors and photodiodes are the core components of flat-panel detectors, which directly affect the final imaging effect and accuracy.

[0003] As the application of X-ray imaging equipment becomes more and more extensive, the operating temperature range is also getting wider. In order to ensure the reliability and accuracy of imaging, it is necessary to maintain a linear relationship between the incident X-ray radiation intensity and the output signal of the X-ray imaging sensor. However, the material of the sensor will be affected by temperature, resulting in the output signal of the sensor being related not only to the incident X-ray intensity, but also to the operating temperature, affecting the final imaging quality. At present, a temperature control module is usually added to the X-ray imaging equipment to maintain the operating temperature of the X-ray imaging sensor at a constant value to ensure the imaging quality, but such a design will increase the size and price of the equipment, and cannot be used in portable devices. Another method is to add a temperature compensation module, send the temperature of the X-ray imaging equipment during operation to the temperature compensation module, and compensate by adjusting the gain value of the amplifier.

[0004] Therefore, it is an urgent problem for those skilled in the art to propose a device and method for calibrating the working characteristics of an X-ray imaging sensor to solve the difficulties existing in the prior art. Summary of the invention

[0005] The purpose of the present invention is to provide a device and method for calibrating the working characteristics of an X-ray imaging sensor, which can effectively reduce the size and price of the X-ray imaging device while ensuring the imaging quality and accuracy, and facilitate the development of portable X-ray imaging equipment.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] A calibration device for the working characteristics of an X-ray imaging sensor, comprising: a high and low temperature test chamber, an X-ray imaging sensor module, an X-ray generator, a bracket, a power supply, and a current acquisition module;

[0008] Among them, the X-ray imaging sensor module is arranged inside the high and low temperature test chamber, and a bracket is arranged below the X-ray imaging sensor module to support the X-ray imaging sensor module; the X-ray generator is located outside the high and low temperature test chamber and opposite to the X-ray imaging sensor module; the power supply is respectively connected to the high and low temperature test chamber and the X-ray imaging sensor module to supply power to the high and low temperature test chamber and the X-ray imaging sensor module respectively; the X-ray imaging sensor module is also connected to the current acquisition module, and the current acquisition module acquires the output current of the X-ray imaging sensor module at different temperatures and different X-ray intensities.

[0009] A method for calibrating the working characteristics of an X-ray imaging sensor, applied to the above-mentioned device for calibrating the working characteristics of an X-ray imaging sensor, comprises the following steps:

[0010] S1. Measure the transmittance of the glass window of the high and low temperature test chamber;

[0011] S2, recording the output current of the X-ray imaging sensor module at different temperatures and different X-ray intensities;

[0012] S3, compensating for the attenuation of X-ray intensity caused by the glass window based on the transmittance in S1;

[0013] S4. Process the obtained multiple sets of data and calculate the functional relationship between the output current of the X-ray imaging sensor and the X-ray intensity and temperature to calibrate the working characteristics of the X-ray imaging sensor module.

[0014] Preferably, S1 specifically includes:

[0015] (1) Do not start the high and low temperature test chamber, open the door of the high and low temperature test chamber, turn on the power switch of the X-ray imaging sensor module, turn on the power switch of the X-ray generator, set the X-ray radiation intensity to the maximum, and record the output current of the X-ray sensor module, which is recorded as I 开 ;

[0016] (2) Do not start the high and low temperature test chamber, close the door of the high and low temperature test chamber, set the X-ray output intensity to the maximum, and record the output current of the X-ray sensor module, which is recorded as I 关 ;

[0017] (3) Calculate the transmittance of the glass window of the high and low temperature test chamber to X-rays, denoted as V 玻璃窗口 , V 玻璃窗口 =I 关 / I 开 .

[0018] Preferably, S2 specifically includes:

[0019] (1) Place the X-ray imaging sensor module into a high and low temperature test chamber and close the door of the high and low temperature test chamber;

[0020] (2) Turn on the power switch of the X-ray imaging sensor module and the power switch of the X-ray generator;

[0021] (3) Divide the temperature test range into N parts, denoted as T i , i = 1-N;

[0022] (4) Divide the X-ray intensity output by the X-ray generator into N parts, denoted as X i , i = 1-N;

[0023] (5) Start the high and low temperature test chamber and set the temperature to T1. After a preset time, record the output current of the X-ray imaging sensor module when the X-ray generator outputs different X-ray intensities, which is recorded as I T1-i , i = 1-N;

[0024] (6) Adjust the temperature of the high and low temperature test chamber to T2, and after the preset time, record the output current of the X-ray imaging sensor module when the X-ray generator outputs different X-ray intensities, recorded as I T2-i , i = 1-N;

[0025] (7) Repeat steps (1)-(6) until all tests at all temperatures are completed and I is obtained. Ti-i , i=1-N.

[0026] Preferably, S3 specifically includes:

[0027] Compensate for different X-ray intensities of the X-ray generator, denoted as X i ′,X′ i =X i ×V 玻璃窗口 , i=1-N.

[0028] Preferably, S4 specifically includes:

[0029] The functional relationship between the output current of the X-ray imaging sensor and the X-ray intensity and temperature is expressed as follows:

[0030] I=b0+b1T+b2X

[0031] Wherein, T is the operating temperature of the X-ray sensor, X′ is the X-ray intensity, I is the output current of the X-ray sensor, b0, b1, and b2 are parameters determined by calculation, and are calculated according to the following formula:

[0032]

[0033] Among them, T i is the ambient temperature during the test, is the average ambient temperature, X i ′ is the X-ray intensity after glass window transmittance compensation, is the average value of the X-ray intensity after glass window transmittance compensation, is the average output current of the X-ray imaging sensor module under different temperatures and different X-ray intensities, l 10 , l 11 , l 12 , l 20 , l 21 , l 22 is the intermediate variable of calculation;

[0034] After obtaining b0, b1, and b2, in actual operation, the actual temperature T 工作 , actual current output I 工作 Substitute the following formula to get the intensity X of the X-ray 工作 , detection and imaging based on X-ray intensity:

[0035]

[0036] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects: The present invention provides a calibration device and method for the working characteristics of an X-ray imaging sensor, which can determine in advance the functional relationship between the output signal of the X-ray imaging sensor and the X-ray radiation intensity and temperature. Different from the prior art, the calibration device for the working characteristics of an X-ray imaging sensor of the present invention does not require an additional hardware module for maintaining a constant temperature and a signal circuit for adjusting the amplifier gain according to the temperature, which can effectively reduce the volume and price of the X-ray imaging device while ensuring the imaging quality and accuracy, and facilitate the development of portable X-ray imaging equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0038] Figure 1 A structural diagram of a calibration device for the working characteristics of an X-ray imaging sensor provided by the present invention;

[0039] Figure 2 A flow chart of a method for calibrating the working characteristics of an X-ray imaging sensor provided by the present invention;

[0040] Among them, 1-high and low temperature test box, 2-X-ray imaging sensor module, 3-X-ray generator, 4-bracket, 5-high and low temperature test box door handle, 6-box door with glass window. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] like Figure 1 As shown, the present invention discloses a calibration device for the working characteristics of an X-ray imaging sensor, comprising: a high and low temperature test chamber 1, an X-ray imaging sensor module 2, an X-ray generator 3, a bracket 4, a power supply, a current acquisition module, a high and low temperature test chamber door handle 5, and a chamber door 6 with a glass window;

[0044] Among them, the X-ray imaging sensor module 2 is arranged inside the high and low temperature test box 1, and a bracket 4 is arranged below the X-ray imaging sensor module 2 for supporting the X-ray imaging sensor module 2; the X-ray generator 3 is located outside the high and low temperature test box 1 and opposite to the X-ray imaging sensor module 2; the power supply is respectively connected to the high and low temperature test box 1 and the X-ray imaging sensor module 2 to supply power to the high and low temperature test box 1 and the X-ray imaging sensor module 2 respectively; the X-ray imaging sensor module 2 is also connected to the current acquisition module, and the current acquisition module acquires the output current of the X-ray imaging sensor module 2 at different temperatures and different X-ray intensities.

[0045] Specifically, the X-ray imaging sensor module includes one or more groups of X-ray imaging sensors.

[0046] Reference Figure 2 As shown, a method for calibrating the working characteristics of an X-ray imaging sensor is applied to the above-mentioned device for calibrating the working characteristics of an X-ray imaging sensor, and includes the following steps:

[0047] S 1. Measure the transmittance of the glass window of the high and low temperature test chamber 1;

[0048] S2, recording the output current of the X-ray imaging sensor module 2 at different temperatures and different X-ray intensities;

[0049] S3, compensating for the attenuation of X-ray intensity by the glass window based on the transmittance in S1;

[0050] S4. Process the obtained multiple sets of data and calculate the functional relationship between the output current of the X-ray imaging sensor and the X-ray intensity and temperature to calibrate the working characteristics of the X-ray imaging sensor module 2.

[0051] Further, in a specific embodiment, S1 specifically includes:

[0052] (1) Do not start the high and low temperature test box 1. Open the door 6 of the high and low temperature test box through the door handle 5. Turn on the power switch of the X-ray imaging sensor module 2 and the power switch of the X-ray generator 3. Set the X-ray radiation intensity to the maximum. Record the output current of the X-ray sensor module 2, which is recorded as I 开 , I 开 =400mA;

[0053] (2) Do not start the high and low temperature test chamber 1, close the door of the high and low temperature test chamber, set the X-ray output intensity to the maximum, and record the output current of the X-ray sensor module, which is recorded as I 关 , I 关 =366mA;

[0054] (3) Calculate the X-ray transmittance of the high and low temperature test chamber door 6 with a glass window, denoted as V 玻璃窗口 , V 玻璃窗口 =I 关 / I 开 =366 / 400=91.5%.

[0055] Furthermore, S2 specifically includes:

[0056] (1) Place the X-ray imaging sensor module 2 into the high and low temperature test chamber 1 and close the door of the high and low temperature test chamber 1;

[0057] (2) Turn on the power switch of the X-ray imaging sensor module 2 and the power switch of the X-ray generator 3;

[0058] (3) Divide the temperature test range of -30℃~70℃ into 11 parts, recorded as T i , T i (i=1-11) -30°C, -20°C, -10°C, 0°C, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C respectively;

[0059] (4) The X-ray intensity output by the X-ray generator is divided into 11 parts, denoted as X i , X i(i=1-11) are 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 0, respectively, the maximum value of the X-ray emission intensity, the unit is 10 -5 Gy;

[0060] (5) Start the high and low temperature test box 1 and set the temperature to -30°C. Ten minutes later, record the X-ray imaging sensor module 2 when the X-ray generator 3 outputs 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, and 0, respectively (unit: 10 -5 Gy) output current, I T1-1 =267.55mA, I T1-2 =247.31mA, I T1-3 =226.98mA, I T1-4 =206.78mA, I T1-5 =187.45mA, I T1-6 =166.83mA, I T1-7 =147.62mA, I T1-8 =128.00mA, I T1-9 =107.68mA, I T1-10 =87.49mA, I T1-11 =0.01mA;

[0061] (6) Adjust the temperature of the high and low temperature test box 1 to -20°C. After ten minutes, record the X-ray imaging sensor module 2 when the X-ray generator 3 outputs 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, and 0 respectively (unit: 10 -5 Gy) output current, I T2-1 =278.20mA, I T2-2 =258.49mA, I T2-3 =237.34mA, I T2-4 =217.02mA, I T2-5 =197.69mA, I T2-6 =177.41mA, I T2-7 =156.68mA, I T2-8 =137.06mA, I T2-9 =116.74mA, I T2-10 =96.55mA, I T2-11 =0.01mA; (7) Repeat steps (1)-(6) until the test at all temperatures is completed and I Ti-i , i=1-11, as shown in Table 1.

[0062] Table 1

[0063]

[0064]

[0065] Furthermore, S3 specifically includes:

[0066] Compensate for different X-ray intensities of X-ray generator 3, denoted as X i ′,X′ i =X i ×V 玻璃窗口 =X i ×91.5%, i=1-11, the data in Table 2 are obtained;

[0067] Table 2

[0068] <![CDATA[X1′]]> <![CDATA[X2′]]> <![CDATA[X3′]]> <![CDATA[X4′]]> <![CDATA[X5′]]> <![CDATA[X6′]]> 915.00 823.50 732.00 640.50 549.00 457.50 <![CDATA[X7′]]> X8′ <![CDATA[X9′]]> <![CDATA[X 10 ′]]> <![CDATA[X 11 ′]]> 366.00 274.50 183.00 91.50 0.00

[0069] Furthermore, S4 specifically includes:

[0070] The functional relationship between the output current of the X-ray imaging sensor and the X-ray intensity and temperature is expressed as follows:

[0071] I=b0+b1T+b2X′

[0072] Wherein, T is the operating temperature of the X-ray sensor, X′ is the X-ray intensity, I is the output current of the X-ray sensor, b0, b1, and b2 are parameters determined by calculation, and are calculated according to the following formula:

[0073]

[0074] Among them, T i is the ambient temperature during the test, is the average ambient temperature, X i ′ is the X-ray intensity after glass window transmittance compensation, is the average value of the X-ray intensity after glass window transmittance compensation, is the average output current of the X-ray imaging sensor module under different temperatures and different X-ray intensities, l 10 , l 11 , l 12 , l 20 , l 21 , l 22 is the intermediate variable of the calculation; substituting the data in Table 1 and Table 2 into the above formula, we get b0=61.561, b1=0.917, b2=0.278;

[0075] After obtaining b0, b1, and b2, in actual operation, the actual temperature T工作 =36℃, actual current output I 工作 =158mA Substitute it into the following formula to get the intensity of X-ray X 工作 , X 工作 =228.53×10 -5 Gy detection and imaging based on X-ray intensity:

[0076]

[0077] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0078] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A calibration device for the working characteristics of an X-ray imaging sensor, characterized in that: include: High and low temperature test chamber, X-ray imaging sensor module, X-ray generator, bracket, power supply, current acquisition module; Among them, the X-ray imaging sensor module is arranged inside the high and low temperature test box, and a bracket is arranged below the X-ray imaging sensor module to support the X-ray imaging sensor module; the X-ray generator is located outside the high and low temperature test box and opposite to the X-ray imaging sensor module; the power supply is respectively connected to the high and low temperature test box and the X-ray imaging sensor module to supply power to the high and low temperature test box and the X-ray imaging sensor module respectively; the X-ray imaging sensor module is also connected to the current acquisition module, and the current acquisition module acquires the output current of the X-ray imaging sensor module at different temperatures and different X-ray intensities.

2. A method for calibrating the working characteristics of an X-ray imaging sensor, applied to the device for calibrating the working characteristics of an X-ray imaging sensor according to claim 1, characterized in that: The following steps are involved: S1. Measure the transmittance of the glass window of the high and low temperature test chamber; S2. Recording the output current of the X-ray imaging sensor module at different temperatures and different X-ray intensities; S3, compensating for the attenuation of X-ray intensity by the glass window based on the transmittance in S1; S4. Process the obtained multiple sets of data and calculate the functional relationship between the output current of the X-ray imaging sensor and the X-ray intensity and temperature to calibrate the working characteristics of the X-ray imaging sensor module.

3. The method for calibrating the working characteristics of an X-ray imaging sensor according to claim 2, characterized in that: S1 specifically includes: (1) Do not start the high and low temperature test box, open the door of the high and low temperature test box, turn on the power switch of the X-ray imaging sensor module, turn on the power switch of the X-ray generator, set the X-ray radiation intensity to the maximum, and record the output current of the X-ray sensor module, which is recorded as I 开 ; (2) The high and low temperature test box is not started, the door of the high and low temperature test box is closed, the X-ray output intensity is set to the maximum, and the output current of the X-ray sensor module is recorded, which is recorded as I 关 ; (3) Calculate the transmittance of the glass window of the high and low temperature test chamber to X-rays, denoted as V 玻璃窗口 , V 玻璃窗口 =I 关 / I 开 .

4. The method for calibrating the working characteristics of an X-ray imaging sensor according to claim 2, characterized in that: S2 specifically includes: (1) placing the X-ray imaging sensor module into a high and low temperature test chamber and closing the door of the high and low temperature test chamber; (2) Turn on the power switch of the X-ray imaging sensor module and the power switch of the X-ray generator; (3) Divide the temperature test range into N parts, denoted as T i , i = 1-N; (4) Divide the X-ray intensity output by the X-ray generator into N parts, denoted as X i , i = 1-N; (5) Start the high and low temperature test box, set the temperature to T1, and after a preset time, record the output current of the X-ray imaging sensor module when the X-ray generator outputs different X-ray intensities, recorded as I Tl-i , i = 1-N; (6) Adjust the temperature of the high and low temperature test box to T2, and after a preset time, record the output current of the X-ray imaging sensor module when the X-ray generator outputs different X-ray intensities, recorded as I T2-i , i = 1-N; (7) Repeat steps (1)-(6) until all tests at all temperatures are completed and I is obtained. Ti-i , i=1-N.

5. The method for calibrating the working characteristics of an X-ray imaging sensor according to claim 2, characterized in that: S3 specifically includes: The X-ray generator is compensated for different X-ray intensities, denoted as X i ′,X′ i =X i ×V 玻璃窗口 , i=1-N.

6. The method for calibrating the working characteristics of an X-ray imaging sensor according to claim 2, characterized in that: S4 specifically includes: The functional relationship between the output current of the X-ray imaging sensor and the X-ray intensity and temperature is expressed as follows: I=b0+b1T+b2X′ Wherein, T is the operating temperature of the X-ray sensor, X′ is the X-ray intensity, I is the output current of the X-ray sensor, b0, b1, and b2 are parameters determined by calculation, and are calculated according to the following formula: Among them, T i is the ambient temperature during the test, is the average ambient temperature, X i ′ is the X-ray intensity after glass window transmittance compensation, is the average value of the X-ray intensity after glass window transmittance compensation, is the average output current of the X-ray imaging sensor module under different temperatures and different X-ray intensities, l 10 , l 11 , l 12 , l 20 , l 21 , l 22 is the intermediate variable of the calculation; After obtaining b0, b1, and b2, in actual operation, the actual temperature T 工作 , actual current output I 工作 Substitute the following formula to get the intensity X of the X-ray 工作 , detection and imaging based on X-ray intensity:

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