A probe-type seafood radiation measuring instrument

Abstract

The present application discloses a probe-type seafood radiation measuring instrument, which relates to the field of food radiation measurement. The probe-type seafood radiation measuring instrument includes a measuring probe, a signal processing system and a display module; wherein the measuring probe includes a stainless steel needle tip, a stainless steel needle tube, a cover, a scintillating optical fiber, a spring and a SiPM chip; when the measuring probe is inserted into the seafood to be measured, the radiation emitted from the inside of the seafood to be measured will pass through the stainless steel shell and enter the scintillating optical fiber, causing the scintillating optical fiber to generate a light signal; the light signal is transmitted to the SiPM chip inside the scintillating optical fiber; the SiPM chip converts the light signal into a current signal and transmits it to the signal processing system; the signal processing system amplifies, filters, calculates and analyzes the current signal to obtain the corresponding radiation dose, and displays it through the display module. The probe-type seafood radiation measuring instrument provided by the present application can measure the radiation dose deeply inside the seafood and quickly give the accurate radiation dose in the seafood food.

Description

Technical Field

[0001] The present application relates to the technical field of food radiation measurement, and in particular to a probe-type seafood radiation measuring instrument. Background Art

[0002] Natural water bodies contain radioactive nuclides. In addition to entering the human body directly through drinking water, radioactive nuclides in water bodies can also enter the human body through food. Radioactive nuclides discharged from the ocean diffuse and enrich in the marine biosphere, and eventually affect the human body in the form of seafood. Therefore, in the context of increasing emissions of radioactive substances, it is necessary to conduct radiation measurements on seafood. For consumers, the safety of seafood can be determined through rapid measurements. For fishery production practitioners, radiation safety inspections of their products can give clear results, enhance consumer confidence, and boost the industry's market prospects. Currently, radiation measurement instruments available on the market are mostly used to measure environmental radiation doses and cannot be used to accurately measure the radiation dose in seafood itself (such as in fresh seafood). Summary of the Invention

[0003] In response to the gap in the current radiation measurement field for radiation detection of seafood, the present application provides a probe-type seafood radiation measuring instrument that can measure the radiation dose deep inside seafood and quickly provide the accurate radiation dose in seafood food.

[0004] To achieve the above objectives, this application provides the following solutions.

[0005] The present application provides a probe-type seafood radiation measuring instrument, comprising: a measuring probe, a signal processing system, and a display module; the measuring probe comprises a stainless steel needle tip, a stainless steel needle tube, a cover, a scintillating optical fiber, a spring, and a SiPM (Silicon photomultiplier) chip;

[0006] The stainless steel needle tip is connected to one end of the stainless steel needle tube, and the cover is connected to the other end of the stainless steel needle tube; the scintillation optical fiber is located in the internal cavity of the stainless steel needle tube; one end of the scintillation optical fiber is fixed by a spring, and the other end is fixed by a protrusion in the internal cavity of the stainless steel needle tube; one end of the spring is embedded in the stainless steel needle tip, and the other end is in contact with and connected to the scintillation optical fiber; a slot is designed at the connection between the scintillation optical fiber and the cover to fix the SiPM chip; the SiPM chip is coupled to the other end of the scintillation optical fiber;

[0007] The signal processing system is connected to the SiPM chip and the display module respectively; when the measuring probe is inserted into the seafood to be tested, the radiation emitted from the inside of the seafood to be tested will pass through the stainless steel shell and enter the scintillation optical fiber, causing the scintillation optical fiber to generate an optical signal; the optical signal is transmitted inside the scintillation optical fiber to the SiPM chip; the SiPM chip converts the optical signal into a current signal and transmits it to the signal processing system; the signal processing system amplifies, filters, and calculates and analyzes the current signal to obtain the corresponding radiation dose, and displays it through the display module.

[0008] Optionally, the scintillating fiber is a lutetium oxide scintillating fiber.

[0009] Optionally, the scintillation optical fiber is in the shape of a cube; the protrusion in the internal cavity of the stainless steel needle tube includes four protrusions, which are in a structure opposing each other, and the other end of the scintillation optical fiber is placed in the middle of the four protrusions, and the four sides of the cube-shaped scintillation optical fiber are supported by the four protrusions.

[0010] Optionally, a reflective layer is provided on the outer surface of the scintillating optical fiber.

[0011] Optionally, optical coupling glue is used to assist coupling between the scintillating optical fiber and the SiPM chip.

[0012] Optionally, the stainless steel needle tube and the stainless steel needle tip are detachably connected; the stainless steel needle tube and the cover are detachably connected.

[0013] Optionally, the signal processing system includes: a high-voltage power supply circuit, an amplifier circuit, a filter circuit, and a single-chip microcomputer; the high-voltage power supply circuit is respectively connected to the SiPM chip and the filter circuit for power supply; the filter circuit is also respectively connected to the amplifier circuit and the single-chip microcomputer;

[0014] The amplifier circuit is used to convert the current signal into a voltage signal and amplify it; the filter circuit is used to convert the amplified voltage signal into a digital signal and perform noise reduction filtering; the filtered digital signal is read by the microcontroller counter; the program burned into the microcontroller obtains the counting rate by dividing the number of counter responses by the measurement time, and the radiation dose is determined based on the counting rate.

[0015] Optionally, the single chip computer determines whether the radiation dose exceeds the standard; if it exceeds the standard, a radiation exceeding standard prompt is output through the display module.

[0016] Optionally, the display module further includes a button; the button is connected to the single chip microcomputer and is used to control the switch of the probe type seafood radiation meter.

[0017] Optionally, the SiPM chip is provided with a temperature compensation module; the temperature compensation module comprises a temperature sensor and a temperature compensation circuit; the temperature compensation circuit is connected to the temperature sensor and the SiPM chip respectively;

[0018] The temperature sensor is packaged together with the SiPM chip and is used to measure the temperature around the SiPM chip and send it to the temperature compensation circuit; the temperature compensation circuit determines the voltage adjustment amount according to the temperature change around the SiPM chip; the voltage adjustment output is input to the SiPM chip to maintain the overvoltage stability of the SiPM chip.

[0019] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0020] The present application provides a probe-type seafood radiation measuring instrument. By arranging a spring and a protrusion in the internal cavity of a stainless steel needle tube, the scintillating optical fiber remains stationary and stable and in stable contact with the SiPM chip. A slot is designed at the connection between the scintillator and the cover to fix the SiPM chip, further deepening the coupling degree between the scintillating optical fiber and the SiPM chip, and improving the detection efficiency and detection accuracy. By using stainless steel as the light-shielding material of the measuring probe shell, the material strength, high corrosion resistance and, most importantly, food safety are taken into account, and the influence of light on the operation of the scintillating optical fiber is avoided, thereby further improving the detection accuracy. In the seafood radiation measurement scenario, by inserting the measuring probe into the inside of the seafood, the measured radiation dose can be seen on the display module after a while. It has the advantages of being easy to carry, simple to use, and having reliable measurement results. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 This is a schematic diagram of the appearance of a probe-type seafood radiation measuring instrument;

[0023] Figure 2 Schematic diagram of the specific structure of the measuring probe;

[0024] Figure 3 This is a schematic diagram of the working process of the probe-type seafood radiation measuring instrument;

[0025] Figure 4 It is a schematic diagram of the structure of the amplifier circuit and the filter circuit;

[0026] Figure 5It is a schematic diagram of the high-voltage power supply circuit structure. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0028] The purpose of this application is to provide a probe-type seafood radiation measuring instrument that can measure the radiation dose deep inside seafood and quickly give the accurate radiation dose in seafood food. It has the advantages of portability and reliable measurement results.

[0029] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0030] Figure 1 This is a schematic diagram of the appearance of a probe-type seafood radiation measuring instrument. Figure 2 The specific structure diagram of the measuring probe is shown in Figure 2. Figure 1 and Figure 2 The present invention provides a probe-type seafood radiation measuring instrument, comprising a measuring probe, a signal processing system, a display module, and a housing 10. The measuring probe comprises a stainless steel needle tip 1, a spring 2, a scintillating optical fiber 3, a SiPM chip 4, a cover 5, a protrusion 6, and a stainless steel needle tube 7. The display module comprises a button 8 and a display screen 9 embedded in the surface of the housing 10. The signal processing system is integrated within the housing 10. The button 8 is connected to a single-chip microcomputer in the signal processing system and is used to control the on / off function of the probe-type seafood radiation measuring instrument.

[0031] like Figure 1 and Figure 2 As shown, the stainless steel needle tip 1 is connected to one end of the stainless steel needle tube 7, and the cover 5 is connected to the other end of the stainless steel needle tube 7. The scintillation optical fiber 3 is located in the internal cavity of the stainless steel needle tube 7. One end of the scintillation optical fiber 3 is squeezed and fixed by the spring 2, and the other end is fixed by the protrusion 6 in the internal cavity of the stainless steel needle tube 7. One end of the spring 2 is embedded in the stainless steel needle tip 1, and the other end is in contact with and connected to the scintillation optical fiber 3. A card slot is designed at the connection between the scintillation optical fiber 3 and the cover 4 to fix the SiPM chip 4. The SiPM chip 4 is coupled and connected to the other end of the scintillation optical fiber 3.

[0032] The signal processing system is connected to the SiPM chip 4 and the display module. When the measurement probe is inserted into the seafood being tested, radiation emitted from within the seafood passes through the stainless steel housing 7 and enters the scintillating fiber 3, causing the scintillating fiber 3 to generate an optical signal. The optical signal is transmitted within the scintillating fiber 3 to the SiPM chip 4. The SiPM chip 4 converts the optical signal into an electric current and transmits it to the signal processing system. The signal processing system amplifies, filters, and calculates and analyzes the current signal to obtain the corresponding radiation dose, which is then displayed on the display screen 9.

[0033] In some preferred embodiments, the scintillating fiber (also called scintillator) 3 is a lutetium oxide scintillating fiber. There are many shapes of scintillators. Figure 2 The scintillator used in the measurement probe shown is a cube, with one end contacting a spring 2 and the other end contacting a SiPM chip 4. The present application incorporates a spring 2 inside the cavity of a stainless steel needle 7 where the scintillator 3 is placed, enabling the spring 2 to help stabilize contact between the scintillator 3 and the SiPM chip 4.

[0034] Furthermore, considering that the scintillator 3 is fragile and difficult to fix, the present application makes four protrusions on the four sides of the cavity (close to the end of the SiPM chip 4) to form a raised portion 6, and uses the four protrusions to keep the scintillator 3 still and stable.

[0035] Specifically, the protruding portion 6 in the internal cavity of the stainless steel needle tube 7 includes four protrusions, which are arranged in pairs in the cylindrical cavity of the stainless steel needle tube 7, i.e., divided into four equal parts. The other end of the scintillation optical fiber 3 (the end in contact with the SiPM chip 4) is placed in the middle of the four protrusions, and the four protrusions support the four sides of the cubic scintillation optical fiber 3 to play a fixing role.

[0036] Furthermore, the present application designs a card slot at the connection between the scintillator 3 and the cover 5 to fix the SiPM chip 4, thereby deepening the coupling degree between the scintillator 3 and the SiPM chip 4 and improving the detection efficiency.

[0037] The lid 5 seals the top of the measurement probe. Because the scintillating fiber 3 needs to couple with the SiPM chip 4, the entire measurement probe, except for the stainless steel tip 1, is hollow. The SiPM chip 4 is nestled in a slot in the lid 5. The lid 5 and the top of the measurement probe are designed to be separable and interlocking, similar to building blocks. Similarly, the stainless steel tip 1 and stainless steel needle tube 7 can also be designed to be separable and interlocking.

[0038] In some preferred embodiments, an optical coupling adhesive may be used to assist coupling between the scintillating optical fiber 3 and the SiPM chip 4. The optical coupling adhesive can not only couple the scintillating optical fiber 3 and the SiPM chip 4 but also has good light transmittance.

[0039] Considering that light may affect the normal operation of the scintillator 3, the present application designs a full light-shielding structure, which is achieved by using stainless steel as the shell material and designing the measurement probe into a sleeve structure.

[0040] Taking into account the requirements of the usage scenario, the measuring probe material needs to have a certain strength, high corrosion resistance and take into account the most important food safety. Therefore, this application chooses to use highly corrosion-resistant food-grade stainless steel 316 as the material for the external needle and needle tube of the measuring probe.

[0041] Considering that light signals may experience some loss when propagating through the scintillator 3, the present invention adds a reflective layer to the outside of the scintillator 3 to increase the reflectivity of light and reduce light signal loss. This can be achieved by wrapping the outer surface of the scintillator 3 with aluminum foil or tin foil.

[0042] Conventional radiation measurement instruments currently available on the market are all gamma dose rate meters. These meters typically use gas detectors as radiation sensors. Gas detectors have low gamma ray detection efficiency and poor energy response, making them suitable for measuring strong radiation environments. However, they suffer from long response times and large statistical errors when measuring weak radiation, making them inaccurate. To address this, the present invention utilizes a high-density lutetium oxide scintillating fiber 3 as its core component. This component generates a weak light signal under radiation conditions. A reflective layer is added to its outer surface to increase the photon collection rate. Furthermore, a SiPM chip 4 is used as a photoelectric device to convert the photoelectric signal. This allows for high detection efficiency in a compact design.

[0043] On the other hand, conventional gamma dose rate meters are non-contact measurement instruments. They are generally located at a certain distance from the surface of the object and can only measure gamma rays in a certain direction. Furthermore, due to the self-absorption of gamma rays by the medium, low-energy gamma rays generated within the object under test may not be detected. To address this, the present application uses a food-grade, high-strength stainless steel needle 1 and stainless steel needle tube 7 to form the outer surface material of the measurement probe. This can be inserted into the interior of the seafood under test for radiation measurement, ensuring light protection while enabling contact measurement, greatly improving detection accuracy.

[0044] Figure 3 The following is a schematic diagram of the working process of the probe type seafood radiation measuring instrument. Figure 3As shown, the present application designs a specific signal processing system for signal reading. When the scintillator 3 detects the radiation rays of the seafood to be tested (radioactive source), it will emit a light signal. After detecting these light signals, the SiPM chip 4 will output the corresponding current signal. In order to keep the SiPM gain constant, the SiPM chip 4 of the present application is also equipped with a temperature compensation module, and the temperature compensation module specifically includes a temperature sensor and a temperature compensation circuit. The temperature compensation circuit realizes high-precision temperature compensation based on the temperature information collected by the temperature sensor near the SiPM chip 4, thereby keeping the SiPM gain constant. Under this condition, the amplification circuit in the signal processing system converts the current signal into a voltage signal and amplifies the voltage signal to achieve high-sensitivity light detection; and is matched with a filtering circuit to reduce the signal noise level, convert the analog signal into a digital signal, and optimize the signal reading. Finally, the single-chip microcomputer analyzes the read signal and outputs the detection result.

[0045] Specifically, the signal processing system includes a high-voltage power supply circuit, an amplifying circuit, a filtering circuit and a single-chip microcomputer. Figure 4 The structure of the amplifier circuit and the filter circuit is shown. The filter circuit is connected to the amplifier circuit and the single chip microcomputer respectively. Specifically, the amplifier circuit includes an operational amplifier U2, a resistor R6, a resistor R7, a capacitor C8, a capacitor C9 and a capacitor C14. The filter circuit includes an operational amplifier U3, resistors R8 to R11, capacitors C10 to C13, capacitors C15 to C16 and an inductor L3. The single chip microcomputer adopts the STM32 series single chip microcomputer. Figure 4 In the embodiment shown, the positive input terminal of the operational amplifier U2 is connected to one end of the resistor R6, and the other end of the resistor R6 is grounded. The negative input terminal of the operational amplifier U2 is connected to one end of the capacitor C8, one end of the capacitor C9, and one end of the resistor R7. The other end of the capacitor C8 is connected to the current signal I output by the SiPM chip 4. SiPM The output terminal of the operational amplifier U2 is connected to the other end of the capacitor C9, the other end of the resistor R7, one end of the capacitor C14 and one end of the resistor R8. The output terminal signal of the operational amplifier U2 is U SiPM . The other end of capacitor C14 is grounded. The positive input of operational amplifier U3 is connected to the other end of resistor R8, one end of capacitor C15, and one end of resistor R11, respectively. The other end of capacitor C15 is grounded. The negative input of operational amplifier U3 is connected to one end of resistor R9 and one end of resistor R10, respectively. The other end of resistor R10 is grounded. The other end of resistor R9 is connected to one end of capacitors C10 to C13 and one end of inductor L3, respectively. The other end of inductor L3 and one end of capacitor C16 are both connected to voltage VOUT2. The other ends of capacitors C10 to C13 and the other end of capacitor C16 are both grounded. The output of operational amplifier U3 is connected to the other end of resistor R11 and the input of the STM32 series microcontroller, respectively.

[0046] The amplifying circuit is used to convert the current signal I output by the SiPM chip 4 into SiPM Convert it into a voltage signal and amplify it to get the amplified voltage signal U SiPM The filter circuit is used to convert the amplified voltage signal U SiPM The signal is converted into a digital signal and subjected to noise reduction filtering. The filtered digital signal is read by the microcontroller counter. A pre-programmed program in the microcontroller calculates the count rate by dividing the number of counter responses by the measurement time. The radiation dose is then determined based on the count rate. Furthermore, the microcontroller is configured to determine whether the radiation dose exceeds the specified limit; if so, a notification indicating the excess radiation is output via display screen 9.

[0047] Figure 5 The high-voltage power supply circuit structure is shown. The high-voltage power supply circuit includes a switching power supply chip U1, resistors R1-R5, capacitors C1-C7, inductors L1-L2, and diode D1. Pin 1 of the switching power supply chip U1 is connected to one end of capacitor C3, the positive electrode of diode D1, and one end of inductor L1. The other end of capacitor C3 is connected to one end of resistor R5. Pin 3 of the switching power supply chip U1 is connected to one end of capacitor C2. Pins 2 and 4 of the switching power supply chip U1, the other end of capacitor C2, and the other end of resistor R5 are all grounded. Pin 5 of the switching power supply chip U1 is connected to one end of resistor R3 and one end of resistor R4. The other end of resistor R4 is connected to one end of capacitors C4-C6, one end of inductor L2, and the cathode of diode D1. Pin 6 of the switching power supply chip U1, one end of capacitor C1, and one end of resistor R1 are all connected to the input voltage VIN. Pin 7 of the switching power supply chip U1 is connected to the other end of resistor R1, one end of resistor R2, and the other end of inductor L1. The other end of inductor L2 is connected to the power input of the SiPM chip and one end of capacitor C7. The other end of capacitor C1, the other end of resistor R3, and the other ends of capacitors C4 through C7 are all grounded.

[0048] The high-voltage power supply circuit uses a monolithic integrated switching voltage regulator chip U1, which has a wide voltage input range (3 to 40V) and a switching frequency of up to 100kHz. R3 and R4 form an output voltage sampling circuit, and the output voltage can be changed by changing the value of R3 or R4. C4-C6 in the circuit are filter capacitors used to reduce the output voltage ripple, of which the electrolytic capacitor C4 filters out low-frequency components, and the ceramic capacitors C5 and C6 are used to filter out high-frequency components. Inductor L2 and capacitor C7 form an LC filter circuit to further reduce voltage ripple. The input of the high-voltage power supply circuit is an external +9V voltage VIN, and its output voltage VCC is divided into two paths, one of which is an output voltage VOUT1 used to power the SiPM chip, and the other is an output voltage VOUT2 used to connect to the filter circuit for power supply.

[0049] In the temperature compensation module, the temperature sensor is packaged behind the SiPM chip 5 and is used to detect temperature changes in the environment in which the chip is located. The temperature compensation circuit implements high-precision temperature compensation based on the temperature information collected by the temperature sensor near the SiPM chip 4, thereby keeping the SiPM gain constant. This is because the breakdown voltage of the SiPM changes with temperature. Since overvoltage = operating voltage - breakdown voltage, if the operating voltage of the SiPM is maintained unchanged, then when the ambient temperature changes, the overvoltage applied to the SiPM will change accordingly. The change in overvoltage will cause fluctuations in the performance of the SiPM, such as gain and detection efficiency. The SiPM gain in this application refers to amplifying the generated photocurrent signal by a certain multiple so that it can be read by the counter of the microcontroller. If the gain changes, more interference signals will be read or high-energy signals that should have been read cannot be counted, resulting in inaccurate radiation dose measurement results, so the gain must be maintained constant.

[0050] Specifically, the temperature compensation module includes a temperature sensor and a temperature compensation circuit. The temperature compensation circuit is connected to the temperature sensor and the SiPM chip, respectively. The temperature sensor is packaged together with the SiPM chip 4 and is used to measure the ambient temperature of the SiPM chip 4 and transmit the information to the temperature compensation circuit. The temperature compensation circuit determines a voltage adjustment value ΔV based on the ambient temperature change of the SiPM chip 4. The voltage adjustment value ΔV is input to the SiPM chip 4, thereby maintaining a constant initial overvoltage according to the formula: "overvoltage = operating voltage - breakdown voltage + voltage adjustment value ΔV."

[0051] Under this condition, if Figure 3 and Figure 4 As shown, the amplifier circuit converts the current signal into a voltage signal, amplifies the readout signal, and achieves highly sensitive light detection. A noise reduction filter circuit is also used to reduce the signal noise level and optimize the signal readout. Finally, the microcontroller reads the signal as radiation intensity information and provides feedback to the user.

[0052] When measuring the radiation dose of seafood, first press button 8 to turn on the signal processing system power, then insert the measurement probe of the present application into the seafood to be measured. The radiation is captured by the measurement probe and processed by the SiPM chip 4 and the signal processing system, and output as radiation dose information at the measured location. The single-chip microcomputer will also provide the user with corresponding safety instructions based on the radiation level of the measured seafood according to current food safety standards. Of course, the probe-type fresh seafood radiation meter of the present application is not only suitable for radiation measurement of seafood, but can also be used for radiation measurement of other radioactive sources (such as other foods or items).

[0053] The radiation from the radiation source causes the scintillating fiber 3 to emit more high-energy photons. These high-energy photons, when striking the SiPM chip 4, generate a larger photocurrent. This photocurrent is converted into a voltage signal by an amplifier circuit, then amplified and filtered, and can be read by the microcontroller counter. A pre-programmed program in the microcontroller calculates the count rate by dividing the number of counter responses by the measurement time. Furthermore, the microcontroller uses a pre-calibrated table comparing count rate and radiation intensity to determine the corresponding radiation intensity, or radiation dose, based on the count rate. The microcontroller can also determine whether the radiation intensity exceeds the specified value. If so, the microcontroller can be connected to an LED display 9 to display a message indicating "Radiation exceeds specified value, unqualified," or to an audible or visual alarm device such as a buzzer to output an alarm signal.

[0054] The present application realizes the radiation measurement of seafood (such as seafood) by providing a probe-type fresh seafood radiation meter, filling the gap in the current radiation measurement field for radiation detection of seafood. In the seafood radiation measurement scenario, by inserting the probe-type fresh seafood radiation meter into the object to be measured, the measured radiation dose can be seen on the display screen 9 after a short wait. The probe-type fresh seafood radiation meter of the present application can realize high-precision contact measurement of the radiation dose in the body of fresh seafood, quickly give the radiation dose in seafood, and has the advantages of small size, light weight, low price, easy to carry, and reliable measurement results.

[0055] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above examples is only intended to help understand the method and core concept of this application. At the same time, for those skilled in the art, based on the concept of this application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A probe-type seafood radiation measuring instrument, characterized in that: include: Measuring probe, signal processing system and display module; the measuring probe includes a stainless steel needle tip, a stainless steel needle tube, a cover, a scintillating optical fiber, a spring and a SiPM chip; The stainless steel needle tip is connected to one end of the stainless steel needle tube, and the cap is connected to the other end of the stainless steel needle tube; the scintillation optical fiber is located in the internal cavity of the stainless steel needle tube; One end of the scintillation fiber is fixed by a spring, and the other end is fixed by a protrusion in the inner cavity of the stainless steel needle tube; one end of the spring is embedded in the stainless steel needle tip, and the other end is in contact with the scintillation fiber; a slot is designed at the connection between the scintillation fiber and the cover to fix the SiPM chip; the SiPM chip is coupled to the other end of the scintillation fiber; The scintillating fiber used is in the shape of a cube, with one end contacting the spring and the other end contacting the SiPM chip; The protrusions in the inner cavity of the stainless steel needle tube include four protrusions, which are arranged in pairs in a structure opposing each other in the cylindrical cavity of the stainless steel needle tube, i.e., dividing the cylindrical cavity into four equal parts. The other end of the scintillation optical fiber is placed between the four protrusions, and the four protrusions support the four sides of the cubic scintillation optical fiber to play a fixing role. The SiPM chip is embedded in the slot on the lid; The cover and the top of the measuring probe are designed to be separable and interlocked; the stainless steel needle tip and the stainless steel needle tube are also designed to be separable and interlocked; Optical coupling glue is used to assist coupling between the scintillating fiber and the SiPM chip; Add a reflective layer to the outside of the scintillating fiber by wrapping aluminum foil or tin foil on the outer surface of the scintillating fiber; The signal processing system is connected to the SiPM chip and the display module respectively; when the measuring probe is inserted into the seafood to be tested, the radiation emitted from the inside of the seafood to be tested will pass through the stainless steel shell and enter the scintillation optical fiber, causing the scintillation optical fiber to generate an optical signal; the optical signal is transmitted inside the scintillation optical fiber to the SiPM chip; the SiPM chip converts the optical signal into a current signal and transmits it to the signal processing system; the signal processing system amplifies, filters, calculates and analyzes the current signal to obtain the corresponding radiation dose, and displays it through the display module The SiPM chip is provided with a temperature compensation module; the temperature compensation module comprises a temperature sensor and a temperature compensation circuit; the temperature compensation circuit is connected to the temperature sensor and the SiPM chip respectively; The temperature sensor is packaged together with the SiPM chip and is used to measure the temperature around the SiPM chip and send it to the temperature compensation circuit; the temperature compensation circuit determines the voltage adjustment amount based on the temperature change around the SiPM chip; the voltage adjustment output is input to the SiPM chip and is used to maintain the overvoltage stability of the SiPM chip according to the formula "overvoltage = operating voltage - breakdown voltage + voltage adjustment amount ΔV".

2. The probe-type seafood radiation measuring instrument according to claim 1, characterized in that: The scintillating optical fiber adopts lutetium oxide scintillating optical fiber.

3. The probe-type seafood radiation measuring instrument according to claim 1, characterized in that: The signal processing system includes: a high-voltage power supply circuit, an amplifier circuit, a filter circuit and a single-chip microcomputer; the high-voltage power supply circuit is respectively connected to the SiPM chip and the filter circuit for power supply; the filter circuit is also respectively connected to the amplifier circuit and the single-chip microcomputer; The amplifier circuit is used to convert the current signal into a voltage signal and amplify it; the filter circuit is used to convert the amplified voltage signal into a digital signal and perform noise reduction filtering; the filtered digital signal is read by the microcontroller counter; the program burned into the microcontroller obtains the counting rate by dividing the number of counter responses by the measurement time, and the radiation dose is determined based on the counting rate.

4. The probe-type seafood radiation measuring instrument according to claim 3, characterized in that: The single chip computer determines whether the radiation dose exceeds the standard; if it exceeds the standard, a radiation exceeding standard prompt is output through the display module.

5. The probe-type seafood radiation measuring instrument according to claim 3, characterized in that: The display module further comprises a button; the button is connected to the single chip microcomputer and is used to control the switch of the probe type seafood radiation measuring instrument.

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