Portable gamma radioactive radiation detector and testing method

Abstract

The invention provides a portable gamma radioactive radiation detector and a testing method. The portable gamma radioactive radiation detector comprises two base plates, a top-layer PCB, a bottom-layer PCB, a silicon PM scintillator detector, a shading piece and a shielding assembly. The top layer PCB and the bottom layer PCB are both arranged between the two base plates; the top layer PCB and the bottom layer PCB are welded and fixed through pin headers and are in signal transmission with each other; the silicon PM scintillator detector is arranged at the center of the bottom PCB and is used for receiving a radiation signal; the shading piece is arranged on the bottom PCB, corresponds to the silicon PM scintillator detector in position and is used for shading the silicon PM scintillator detector; the shielding assemblies are arranged on the two sides of the bottom layer PCB respectively and correspond to the silicon PM scintillator detector in position, the shielding assembly close to the top layer PCB wraps the outer side of the shading piece and is used for blocking external electromagnetic interference, the detector can efficiently block ambient light interference and crosstalk of GHz-level radio frequency signals of mobile terminal equipment on small signals of the silicon PM scintillator detector, and the detection accuracy is improved. And the measurement precision and stability of the equipment are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of gamma radioactivity detection, and in particular to a portable gamma radioactivity detector and a testing method. Background Art

[0002] Gamma radiation detectors are specialized devices used to accurately measure gamma radiation doses in the environment. With the widespread application of nuclear technology in energy, healthcare, industry, and scientific research, the demand for real-time monitoring of radiation levels is growing. Portable gamma radiation detectors, with their fast response and ease of operation, are ideal tools for on-site radiation monitoring, providing critical support for ensuring personnel safety and environmental protection.

[0003] A radioactivity detection device with publication number CN222145237U is mainly composed of a measuring tube, a sample pressing plate, and a radioactivity detector; the radioactivity detector is composed of a protective film, a scintillator, a light guide, a photomultiplier tube, and a measuring circuit; the radioactivity detector is installed in the measuring tube, and the sample is directly placed in the measuring tube after being crushed, pressed with a sample pressing plate, and covered on the radioactivity detector to directly measure the radioactivity of the sample.

[0004] Currently available radioactivity detection devices are large in size, inconvenient to carry and use, and small portable detectors cannot block ambient light interference and crosstalk from GHz-level radio frequency signals of mobile devices on the small signals of silicon PM scintillator detectors, reducing the measurement accuracy and stability of the equipment. Summary of the Invention

[0005] In view of this, the present invention proposes a portable γ-radiation detector and testing method, which can effectively block the interference of ambient light and the crosstalk of GHz-level radio frequency signals of mobile devices on the small signals of silicon PM scintillator detectors, solve the electromagnetic compatibility problem in a small space, and improve the measurement accuracy and stability of the equipment.

[0006] The technical solution of the present invention is implemented as follows: In a first aspect, the present invention provides a portable gamma radioactive radiation detector, comprising two pads, a top PCB board, a bottom PCB board, a silicon PM scintillator detector, a light shielding member, and a shielding assembly; The two pads are arranged at a relative interval; The top PCB board and the bottom PCB board are both arranged between the two pads and are arranged in parallel and spaced apart. The bottom PCB board is used for collecting radiation signals; the top PCB board is used for processing measurement results; and the top PCB board and the bottom PCB board are fixed and fixed to each other through pin header welding and signal transmission. The silicon PM scintillator detector is set at the center of the bottom PCB board to receive the radiation signal; The light shielding member is arranged on the bottom PCB board and is arranged corresponding to the position of the silicon PM scintillator detector, and is used to shield the silicon PM scintillator detector; The shielding components are located on both sides of the bottom PCB board and are set corresponding to the positions of the silicon PM scintillator detectors. The shielding component close to the top PCB board is wrapped around the outside of the shading member to block external electromagnetic interference.

[0007] On the basis of the above technical solution, preferably, a window is provided on the top PCB board, the position of the window is set corresponding to the position of the shading member, the outer contour shape of the shading member matches the inner contour shape of the window, and the shading member abuts against the inside of the window.

[0008] On the basis of the above technical solution, preferably, the shielding assembly includes a first shielding cover and a second shielding cover, wherein: The first shielding cover and the second shielding cover are both welded and fixed on the bottom PCB board, and are respectively arranged on both sides of the light shielding member; The first shielding cover and the second shielding cover have opposite sides with notches, the first shielding cover and the second shielding cover are in contact with each other, and the shading element is in contact with the notches to form a fully enclosed shielding environment.

[0009] On the basis of the above technical solution, preferably, the bottom PCB board is further provided with a signal acquisition module, a data conversion module, an energy window comparison module, a power supply module and a voltage conversion module, wherein, The output end of the silicon PM scintillator detector is electrically connected to the input end of the signal acquisition module for collecting radiation signals; The input end of the data conversion module is electrically connected to the output end of the signal acquisition module, and is used to amplify the radiation signal; The energy window comparison module has a multi-channel comparator, and the output end of the data conversion module is electrically connected to the input end of the multi-channel comparator of the energy window comparison module, so as to compare and collect the amplitude of each pulse signal; The output end of the power supply module is electrically connected to the input end of the voltage conversion module, and the output end of the voltage conversion module is electrically connected to the power supply end of the silicon PM scintillator detector for supplying power to the silicon PM scintillator detector.

[0010] On the basis of the above technical solution, preferably, the shielding assembly also includes a third shielding cover, wherein the third shielding cover is welded on the side of the bottom PCB board away from the shading member, and the shading member is located on the outside of the silicon PM scintillator detector and the data conversion module, thereby fully shielding the interference signal.

[0011] On the basis of the above technical solution, preferably, a central control module and a Type C interface are further provided on the top PCB board, wherein the input end of the central control module is electrically connected to the output end of the energy window comparison module through a pin header, the output end of the central control module is electrically connected to the input end of the Type C interface, and the output end of the Type C interface is electrically connected to the communication interface of the mobile device end, for communicating with the mobile device end and drawing power, and the Type C interface is arranged away from the side of the shielding component.

[0012] On the basis of the above technical solution, preferably, the bottom PCB board is further provided with a temperature sensor and a digital potentiometer, the output end of the temperature sensor is electrically connected to the central control module and the input end of the digital potentiometer respectively, the output end of the digital potentiometer is electrically connected to the control end of the data conversion module, the temperature sensor is used to measure the temperature of the bottom PCB board, and adjust the amplification factor of the data conversion module through the digital potentiometer according to the temperature measurement result.

[0013] On the basis of the above technical solution, preferably, it also includes a shell, wherein the interior of the shell is hollow and has openings on both sides; two pads are respectively abutted against the openings on both sides of the shell, and the two pads are fixed to the shell threads by bolts to form a closed shielding environment.

[0014] In a second aspect, the present invention further provides a method for testing a portable gamma radiation detector, which is implemented using the portable gamma radiation detector, and the method comprises the following steps: S1, the radiation signal collected by the scintillator in the silicon PM scintillator detector is converted into an optical signal, and the photoelectric conversion and preliminary amplification are completed by the silicon photomultiplier tube to obtain a preliminary amplified pulse signal; S2, inputting the preliminary amplified pulse signal into the data conversion module for secondary amplification to obtain an analog pulse signal; S3, inputting the analog pulse signals in parallel into the multi-channel comparators of the energy window comparison module, each comparator being preset with a corresponding threshold range. The comparator compares the amplitude of each analog pulse signal according to the corresponding threshold range and assigns a corresponding energy window to each analog pulse signal; S4, each channel of the multi-channel comparator is provided with a counter, and the central control module obtains the counter value once per second to obtain the pulse count value of each energy window per second; S5, calibrating the dose rate contribution coefficients of multiple energy windows according to the standard radiation field, and calculating the comprehensive dose rate value according to the pulse count of each energy window per second and the dose rate contribution coefficient of the corresponding energy window; S6, the comprehensive dose rate value is displayed on the external mobile device through the Type C interface.

[0015] On the basis of the above technical solution, preferably, the number of the multi-channel comparators of the energy window comparison module is 8, and the threshold ranges of the multi-channel comparators are set continuously to evenly divide the energy range.

[0016] The portable gamma radiation detector and testing method of the present invention have the following beneficial effects compared with the prior art: (1) The compact layout of the double-layer PCB board and the pin header welding connection achieve structural miniaturization, improve portability, and the shading parts and shielding components are used for collaborative protection, which can effectively block the interference of ambient light and the crosstalk of the GHz-level radio frequency signal of the mobile terminal device to the small signal of the silicon PM scintillator detector, solve the electromagnetic compatibility problem in a small space, and improve the measurement accuracy and stability of the equipment; (2) By setting up the temperature sensor and digital potentiometer, a control closed loop of temperature compensation and dynamic adjustment of signal amplification is formed, ensuring that the signal can maintain stable gain characteristics under temperature fluctuation environment; effectively avoiding the signal distortion of traditional radiation detectors when the temperature changes; (3) By adopting a multi-channel amplitude comparator, the signal processing process is simplified. Under the constraints of limited space and power consumption, the pulse amplitude is used to approximately replace the energy. The energy window is divided by reasonably setting the threshold, and the dose rate contribution coefficient of each energy window is calibrated in combination with the standard radiation field. While ensuring the measurement accuracy, the hardware complexity and data processing volume are greatly reduced, which not only improves the portability and environmental adaptability of the equipment, but also realizes efficient radiation dose rate measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 any creative work.

[0018] Figure 1 A perspective view of a portable gamma radiation detector according to the present invention; Figure 2 This is a schematic structural diagram of the top PCB board of the portable gamma radiation detector of the present invention; Figure 3 This is a top cross-sectional view of the bottom PCB board of the portable gamma radiation detector of the present invention; Figure 4 An exploded view of the shielding assembly and light shielding member of the portable gamma radiation detector of the present invention; Figure 5 This is a bottom view of the bottom PCB board of the portable gamma radiation detector of the present invention; Figure 6 Schematic diagram of the housing of the portable gamma radiation detector of the present invention; Figure 7 This is a circuit diagram of the portable gamma radiation detector of the present invention; Figure 8 This is a flow chart of the detection method of the portable gamma radiation detector of the present invention. DETAILED DESCRIPTION

[0019] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described 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 making creative efforts are within the scope of protection of the present invention.

[0020] like Figure 1-7 As shown, in the first aspect of the present invention, the present invention provides a portable gamma radioactive radiation detector, comprising two pads 1, a top PCB board 2, a bottom PCB board 3, a silicon PM scintillator detector 4, a light shielding member 5 and a shielding assembly 6; the two pads 1 are arranged at a relative interval; the top PCB board 2 and the bottom PCB board 3 are both arranged between the two pads 1 and are arranged in parallel and at a distance, the bottom PCB board 3 is used for radiation signal acquisition; the top PCB board 2 is used for processing the measurement results; and the top PCB board 2 and the bottom PCB board 3 are fixed and signal transmitted by pin welding; the silicon PM scintillator detector 4 is arranged at the center of the bottom PCB board 3 for receiving radiation signals; the light shielding member 5 is arranged on the bottom PCB board 3 and is arranged corresponding to the position of the silicon PM scintillator detector 4 for shielding the silicon PM scintillator detector 31; the shielding assembly 6 is arranged on both sides of the bottom PCB board 3 and is arranged corresponding to the position of the silicon PM scintillator detector 4, and the shielding assembly 6 close to the top PCB board 2 is wrapped around the outside of the light shielding member 5 for blocking external electromagnetic interference.

[0021] It should be noted that the signal of such small portable detectors is very small. If it is interfered with by external factors, it will lead to serious measurement inaccuracies, resulting in a large number of false triggers and false counts. In addition, the GHz-level high-power RF signals emitted by the antennas of mobile devices such as mobile phones are difficult to isolate in the small structure of portable devices with PCB anti-interference and filtering design alone. Therefore, it is necessary to adopt a layout where the device is located away from the interference source, and use an aluminum alloy or copper shielding structure to shield the antenna signal, thereby preventing the small signal output by the silicon PM scintillator detector from being affected.

[0022] It can be understood that the top PCB board 2 and the bottom PCB board 3 in this embodiment are limited by the pads 1 on both sides and are connected by pin welding to form a compact structure; the top PCB board 2 includes a TypeC interface for connecting to the mobile terminal to realize communication and power supply, and is equipped with an ARM processor responsible for data processing and communication protocol implementation. The bottom PCB board 3 integrates a silicon PM scintillator detector 4, a signal acquisition module 31, and a data conversion module 32 for collecting radiation signals; wherein, the silicon PM scintillator detector 4 is arranged at the center of the bottom PCB board 3 for receiving radiation signals; its output signal is processed by the signal acquisition module 31 and the data conversion module 32, and then transmitted to the top PCB board 2 for further data processing; the shading member 5 is arranged on the bottom PCB board 3, corresponding to the position of the silicon PM scintillator detector 4, for shading; the shielding component 6 is arranged on both sides of the bottom PCB board 3, and the shielding component close to the top PCB board 2 is wrapped around the outside of the shading member 5 to block external electromagnetic interference and protect the silicon PM scintillator detector 4 from environmental interference.

[0023] In this embodiment, the compact layout of the double-layer PCB board and the pin-head welding connection are used to achieve structural miniaturization and improve portability. The collaborative protection of the light-shielding member and the double-layer shielding component can effectively block the interference of ambient light and the crosstalk of the GHz-level radio frequency signal of the mobile device to the small signal of the silicon PM scintillator detector, thereby solving the electromagnetic compatibility problem in a small space, ensuring a low false trigger rate and high measurement accuracy, and is particularly suitable for portable radiation monitoring scenarios that require plug-in and measurement and are susceptible to complex electromagnetic environments.

[0024] The silicon PM scintillator detector 4 in this embodiment is composed of a standardized 6mm×6mm×6mm YSO scintillator and a SiPM detection module. The YSO crystal is arranged inside the light-shielding member 5. The YSO scintillator is used to generate fluorescence of a specific band by stimulating internal atoms under the action of radiation rays. This part of the photons often corresponds to the peak detection wavelength of the selected SiPM detection module, and is thus converted into an electrical signal with considerable amplitude in the SiPM module with the help of the avalanche photoelectric effect of a large number of photodiodes, that is, a pulse signal after preliminary amplification.

[0025] This embodiment also includes a shell 7, which is hollow inside and has openings on both sides; two pads 1 are respectively abutted against the openings on both sides of the shell 1, and the two pads 1 are threadedly fixed to the shell 1 by bolts to form a closed shielding environment.

[0026] It should be noted that the outer shell 7 is rigidly connected to the pad 1 by bolts to form an impact-resistant frame, and the open design allows for quick disassembly of the pad 1, which facilitates the replacement of the silicon PM scintillator detector 4 and the shielding assembly 6, thereby improving maintenance efficiency; and the outer shell 7 is made of a thin aluminum alloy shell, and the continuous conductor formed by the outer shell 7 and the pad 1 and the internal double-layer shielding assembly 6 form a Faraday cage effect, which synergistically blocks GHz-level radio frequency interference and environmental electromagnetic noise, and cooperates with the shading member 5 to construct multiple protections, thereby improving the signal-to-noise ratio of weak signal detection and improving the accuracy of signal acquisition.

[0027] In this embodiment, a window 200 is provided on the top PCB board 2. The position of the window 200 corresponds to the position of the shading member 5. The outer contour of the shading member 5 matches the inner contour of the window 200, and the shading member 5 abuts against the inside of the window 200.

[0028] It should be noted that in this embodiment, the window 200 opened on the top PCB board 2 corresponds to the position of the shading member 5 and matches the contour, thereby realizing the precise docking of the shading member 5 with the top PCB board 2, which not only ensures the effective shading of the silicon PM scintillator detector 4 by the shading member 5, but also optimizes the internal space layout, maintains the compactness of the structure while improving the optical shielding performance, and reduces the influence of ambient light interference on the measurement results.

[0029] The shielding assembly 6 of this embodiment includes a first shielding cover body 61 and a second shielding cover body 62, wherein the first shielding cover body 61 and the second shielding cover body 62 are both welded and fixed on the bottom PCB board 3, and are respectively arranged on both sides of the shading member 5; the first shielding cover body 61 and the second shielding cover body 62 are respectively provided with a notch 600 on the opposite side, and the first shielding cover body 61 and the second shielding cover body 62 are abutted on the opposite side, and the shading member 5 abuts in the notch 600 to form a fully enclosed shielding environment.

[0030] It should be noted that the shielding assembly 6 of this embodiment is fixed to the underlying PCB board 3 by welding the first shielding cover body 61 and the second shielding cover body 62 and is arranged on both sides of the shading member 5. The notches 600 on both sides of the cover body are designed to fit in with the shading member 5 to form a fully enclosed electromagnetic shielding structure for the silicon PM scintillator detector 4. It not only blocks external electromagnetic interference through physical shielding, but also achieves electrical continuity through the metal contact surface, effectively eliminating the risk of electromagnetic leakage and providing a reliable electromagnetic compatibility environment for radiation measurement.

[0031] The bottom PCB board 3 in this embodiment is also provided with a signal acquisition module 31, a data conversion module 32, an energy window comparison module 33, a power supply module 34 and a voltage conversion module 35, wherein the output end of the silicon PM scintillator detector 4 is electrically connected to the input end of the signal acquisition module 31 for collecting radiation signals; the input end of the data conversion module 32 is electrically connected to the output end of the signal acquisition module 31 for amplifying and processing the radiation signals; the energy window comparison module 33 has a multi-channel comparator, and the output end of the data conversion module 32 is electrically connected to the input end of the multi-channel comparator of the energy window comparison module 33 respectively for comparing and collecting the amplitude of each pulse signal; the output end of the power supply module 33 is electrically connected to the input end of the voltage conversion module 34, and the output end of the voltage conversion module 34 is electrically connected to the power supply end of the silicon PM scintillator detector 4 for powering the silicon PM scintillator detector 4.

[0032] It should be noted that the bottom PCB board 3 integrates a signal acquisition module 31, a data conversion module 32, an energy window comparison module 33, a power supply module 34 and a voltage conversion module 35, forming an integrated radiation signal processing and power supply system. The output end of the silicon PM scintillator detector 4 is electrically connected to the input end of the signal acquisition module 31 to achieve accurate acquisition of the radiation signal; the data conversion module 32 amplifies the collected radiation signal to enhance the signal strength and provide reliable data for subsequent analysis; the energy window comparison module 33 has a built-in multi-channel comparator to perform multi-level comparison on the amplified signal pulse amplitude to achieve rapid definition of the energy range, effectively simplifying the complex signal processing process of the traditional ADC+FPGA, while reducing the impact of environmental interference on the measurement results, and improving the real-time and accuracy of the radiation dose rate measurement; the power supply module 34 and the voltage conversion module 35 work together to provide a stable and adjustable voltage for the silicon PM scintillator detector 4 to ensure stable operation of the detector in different environments.

[0033] The shielding assembly 6 in this embodiment also includes a third shielding cover 63, wherein the third shielding cover 63 is welded on the side of the bottom PCB board 3 away from the shading member 5, and the shading member 5 is located on the outside of the silicon PM scintillator detector 4 and the data conversion module 32, thereby fully shielding the interference signal.

[0034] It should be noted that the provision of the third shielding cover 63 not only increases the device's resistance to external electromagnetic interference, but also reduces crosstalk between internal signals, especially the electromagnetic radiation that may be generated by the data conversion module 32 during signal processing, thereby achieving the purpose of suppressing interference; the shading member 5, the silicon PM scintillator detector 4 and the data conversion module 32 are all in electromagnetic shielding, ensuring a pure environment for radiation signal collection and processing, thereby improving the measurement accuracy and stability of the equipment, and providing reliable support for portable γ-radiation detectors in complex electromagnetic environments.

[0035] A central control module 21 and a Type C interface 22 are also provided on the top PCB board 2 in this embodiment, wherein the input end of the central control module 21 is electrically connected to the output end of the energy window comparison module 33 through a pin header, the output end of the central control module 21 is electrically connected to the input end of the Type C interface 22, and the output end of the Type C interface 22 is electrically connected to the communication interface of the mobile device end, for communicating with the mobile device end and drawing power, and the Type C interface 22 is arranged away from the side of the shielding component 6.

[0036] It can be understood that the central control module 21 is responsible for receiving and preliminarily processing the radiation dose rate data from the underlying PCB board 3, and the central control module 21 transmits the processed data to the mobile device through the TypeC interface 22 for further analysis and display. At the same time, various instructions issued by the mobile device can also be received through the TypeC interface 22 to realize communication transmission. In addition, the device draws power from the mobile device through the TypeC interface 22. The TypeC interface 22 is set away from the shielding component 6. While ensuring that the effective detection position is close to the center of the device, it effectively avoids the interference caused by the mobile terminal antenna signal being transmitted into the device through the TypeC interface 22, thereby ensuring the stability and accuracy of data transmission.

[0037] Among them, the spatial layout of the detector must meet the following requirements: the source of the interference signal is the top-layer PCB board 2 below, the silicon PM scintillator detector 4 must be placed in the center of the device as much as possible to ensure that the silicon PM scintillator detector 4 has a consistent response level in all directions, and the welding area of ​​the shielding component 6 cannot be close to the edge of the PCB board, otherwise the copper foil will be exposed and the shielding effect will be lost. The silicon PM scintillator detector 4 is arranged inside the shielding component 6. Secondly, the Type C interface 22 is set away from the side of the shielding component 6. On the one hand, the degree of electromagnetic interference is inversely proportional to the distance, and on the other hand, the circuit loop area formed on the PCB is small, which suppresses the induced signal.

[0038] The bottom PCB board 3 in this embodiment is also provided with a temperature sensor 36 and a digital potentiometer 37. The output end of the temperature sensor 36 is electrically connected to the central control module 21 and the input end of the digital potentiometer 37, respectively. The output end of the digital potentiometer 37 is electrically connected to the control end of the data conversion module 32. The temperature sensor 36 is used to measure the temperature of the bottom PCB board 3 and adjust the amplification factor of the data conversion module 32 through the digital potentiometer 37 according to the temperature measurement result.

[0039] It should be noted that, considering that the gain of the SiPM detection module will change with temperature, the same crystal and the same structure are used, but at different temperatures, the signal amplitude corresponding to the same energy ray is different, which will lead to inaccurate final energy response and energy spectrum offset. In this embodiment, a temperature sensor 36 and a digital potentiometer 37 are set to form a closed-loop control system for temperature compensation and dynamic adjustment of signal amplification. The temperature sensor 36 monitors the operating temperature of the underlying PCB board 3 in real time, and synchronously transmits the temperature data to the central control module 21 and the digital potentiometer 37. The digital potentiometer 37 dynamically changes the resistance value according to the real-time temperature feedback. The resistance value is located in the main amplifier feedback loop with the data conversion module 32, thereby controlling the amplification factor of the data conversion module 32 to ensure that the signal can still maintain a stable gain characteristic in a temperature fluctuation environment; it effectively solves the problem of inaccurate energy response and energy spectrum offset of traditional radiation detectors when the temperature changes.

[0040] like Figure 8 As shown, in a second aspect, the present invention further provides a method for testing a portable gamma radiation detector, which is implemented using the portable gamma radiation detector, and the method comprises the following steps: S1, the radiation signal collected by the scintillator in the silicon PM scintillator detector 4 is converted into an optical signal, and the photoelectric conversion and preliminary amplification are completed by the silicon photomultiplier tube to obtain a preliminary amplified pulse signal; S2, inputting the preliminary amplified pulse signal into the data conversion module 32 for secondary amplification to obtain an analog pulse signal; S3, the analog pulse signals are input in parallel to the multiple comparators of the energy window comparison module 33. Each comparator is preset with a corresponding threshold range. The comparator compares the amplitude of each analog pulse signal according to the corresponding threshold range and assigns a corresponding energy window to each analog pulse signal; S3, each channel of the multi-channel comparator is provided with a counter, and the central control module 21 obtains the counter value once per second to obtain the pulse count value of each energy window per second; S4, calibrating the dose rate contribution coefficients of multiple energy windows according to the standard radiation field, and calculating the comprehensive dose rate value according to the pulse count of each energy window per second and the dose rate contribution coefficient of the corresponding energy window; The expression is:

[0041] Where, C i For the i The pulse count value of the energy window, k i is the corresponding contribution coefficient.

[0042] S5, the comprehensive dose rate value is displayed on an external mobile device through the Type C interface 22 to display the test result.

[0043] It should be noted that the traditional solution requires the collection of the complete signal waveform and complete integration to obtain the waveform and energy information of the pulse. Different pulse energies correspond to different channels in the energy spectrum. However, in this embodiment, considering that only gamma rays are measured, the waveforms of the output signals of the relevant detectors are not much different. In the case of a single purpose, the pulse amplitude can approximately replace the pulse energy, and by reasonably setting the comparison threshold of the pulse amplitude, an effect similar to the energy spectrum channel address can be achieved.

[0044] This embodiment simplifies the signal processing process by replacing the traditional ADC+FPGA architecture with a multi-channel amplitude comparator. Under the constraints of limited space and power consumption, pulse amplitude is used to approximately replace energy. Energy windows are divided by reasonably setting thresholds, and the dose rate contribution coefficient of each energy window is calibrated in combination with a standard radiation field. While ensuring measurement accuracy, the hardware complexity and data processing volume are greatly reduced, which not only improves the portability and environmental adaptability of the device, but also realizes efficient radiation dose rate measurement.

[0045] Specifically, the energy window comparison module 33 in this embodiment includes eight multi-channel comparators, and the threshold ranges of the multi-channel comparators are continuously set to evenly divide the energy range.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A portable gamma radiation detector, characterized in that: It includes two pads (1), a top PCB board (2), a bottom PCB board (3), a silicon PM scintillator detector (4), a light shielding member (5) and a shielding assembly (6); The two pads (1) are arranged at a relative interval; The top PCB board (2) and the bottom PCB board (3) are both arranged between the two pads (1) and are arranged in parallel and spaced apart. The bottom PCB board (3) is used for collecting radiation signals; the top PCB board (2) is used for processing measurement results; and the top PCB board (2) and the bottom PCB board (3) are fixed and signal transmitted by pin welding. A silicon PM scintillator detector (4) is arranged at the center of the bottom PCB board (3) and is used to receive radiation signals; The light shielding member (5) is arranged on the bottom PCB board (3) and is arranged corresponding to the position of the silicon PM scintillator detector (4), and is used to shield the silicon PM scintillator detector (31); The shielding components (6) are arranged on both sides of the bottom PCB board (3) and are both arranged corresponding to the positions of the silicon PM scintillator detector (4). The shielding component (6) close to the top PCB board (2) is wrapped around the outside of the light shielding member (5) to block external electromagnetic interference.

2. The portable gamma radiation detector according to claim 1, wherein: A window (200) is provided on the top PCB board (2), the position of the window (200) is arranged corresponding to the position of the shading member (5), the outer contour shape of the shading member (5) matches the inner contour shape of the window (200), and the shading member (5) abuts against the inside of the window (200).

3. The portable gamma radiation detector according to claim 1, wherein: The shielding assembly (6) comprises a first shielding cover (61) and a second shielding cover (62), wherein: The first shielding cover (61) and the second shielding cover (62) are both welded and fixed on the bottom PCB board (3), and are respectively arranged on both sides of the light shielding member (5); A notch (600) is provided on one side opposite to the first shielding cover (61) and the second shielding cover (62). The first shielding cover (61) and the second shielding cover (62) are in contact with each other on their opposite sides, and the light shielding member (5) is in contact with the inside of the notch (600), forming a fully enclosed shielding environment.

4. The portable gamma radiation detector according to claim 1, wherein: The bottom PCB board (3) is further provided with a signal acquisition module (31), a data conversion module (32), an energy window comparison module (33), a power supply module (34) and a voltage conversion module (35), wherein: The output end of the silicon PM scintillator detector (4) is electrically connected to the input end of the signal acquisition module (31) for collecting radiation signals; The input end of the data conversion module (32) is electrically connected to the output end of the signal acquisition module (31) and is used to amplify the radiation signal; The energy window comparison module (33) has a multi-channel comparator, and the output end of the data conversion module (32) is electrically connected to the input end of the multi-channel comparator of the energy window comparison module (33) for comparing and collecting the amplitude of each pulse signal; The output end of the power supply module (33) is electrically connected to the input end of the voltage conversion module (34), and the output end of the voltage conversion module (34) is electrically connected to the power supply end of the silicon PM scintillator detector (4) for supplying power to the silicon PM scintillator detector (4).

5. The portable gamma radiation detector according to claim 4, characterized in that: The shielding assembly (6) further comprises a third shielding cover (63), wherein the third shielding cover (63) is welded to a side of the bottom PCB board (3) away from the light shielding member (5), and the light shielding member (5) is located outside the silicon PM scintillator detector (4) and the data conversion module (32), thereby providing comprehensive shielding against interference signals.

6. The portable gamma radiation detector according to claim 5, characterized in that: The top PCB board (2) is further provided with a central control module (21) and a Type C interface (22), wherein the input end of the central control module (21) is electrically connected to the output end of the energy window comparison module (33) via a pin header, the output end of the central control module (21) is electrically connected to the input end of the Type C interface (22), and the output end of the Type C interface (22) is electrically connected to the communication interface of the mobile device end, for communicating with the mobile device end and drawing power, and the Type C interface (22) is provided away from the side of the shielding component (6).

7. The portable gamma radiation detector according to claim 6, characterized in that: The bottom PCB board (3) is further provided with a temperature sensor (36) and a digital potentiometer (37). The output end of the temperature sensor (36) is electrically connected to the central control module (21) and the input end of the digital potentiometer (37), respectively. The output end of the digital potentiometer (37) is electrically connected to the control end of the data conversion module (32). The temperature sensor (36) is used to measure the temperature of the bottom PCB board (3) and adjust the amplification factor of the data conversion module (32) through the digital potentiometer (37) according to the temperature measurement result.

8. The portable gamma radiation detector according to claim 1, wherein: It also includes a shell (7), wherein the shell (7) is hollow inside and has openings on both sides; two pads (1) are respectively abutted against the openings on both sides of the shell (1), and the two pads (1) are screw-fixed to the shell (1) by bolts to form a closed shielding environment.

9. A method for testing a portable gamma radiation detector, implemented using the portable gamma radiation detector according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: S1, the radiation signal collected by the scintillator in the silicon PM scintillator detector (4) is converted into an optical signal, and the photoelectric conversion and preliminary amplification are completed by the silicon photomultiplier tube to obtain a preliminary amplified pulse signal; S2, inputting the preliminary amplified pulse signal into the data conversion module (32) for secondary amplification to obtain an analog pulse signal; S3, inputting the analog pulse signals in parallel into the multi-channel comparators of the energy window comparison module (33), each comparator being preset with a corresponding threshold range, and the comparator comparing the amplitude of each analog pulse signal according to the corresponding threshold range, and assigning a corresponding energy window to each analog pulse signal; S3, each channel of the multi-channel comparator is provided with a corresponding counter, and the counter value is obtained once per second through the central control module (21), thereby obtaining the pulse count value of each energy window per second; S4, calibrating the dose rate contribution coefficients of multiple energy windows according to the standard radiation field, and calculating the comprehensive dose rate value according to the pulse count of each energy window per second and the dose rate contribution coefficient of the corresponding energy window; S5, the integrated dose rate value is transmitted to an external mobile device via the TypeC interface (22) to display the test result.

10. The method for testing a portable gamma radiation detector according to claim 9, wherein: The number of the multi-channel comparators of the energy window comparison module (33) is 8, and the threshold ranges of the multi-channel comparators are set continuously to evenly divide the energy range.

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