Probe-type marine product radiation measuring instrument

Abstract

The invention discloses a probe type seafood radiation measuring instrument, and relates to the field of food radiation measurement. The probe type marine product radiation measuring instrument comprises a measuring probe, a signal processing system and a display module, wherein the measuring probe comprises a stainless steel needle tip, a stainless steel needle tube, a cover, a scintillation optical fiber, a spring and an SiPM chip; when the measuring probe is inserted into a marine product to be measured, radiation emitted by the interior of the marine product to be measured can penetrate through the stainless steel shell and enter the scintillation optical fiber, so that the scintillation optical fiber generates an optical signal; the optical signal is transmitted to the SiPM chip in the scintillation optical fiber; the SiPM chip converts the optical signal into a current signal and transmits the current signal to the signal processing system; the signal processing system carries out amplification, filtering and calculation analysis processing on the current signal to obtain a corresponding radiation dose, and the radiation dose is displayed through the display module. The probe-type seafood radiation measuring instrument provided by the invention can deeply measure the radiation dose in the seafood, and can quickly give the accurate radiation dose in the seafood.

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, it is necessary to conduct radiation measurements on seafood in the context of increasing emissions of radioactive substances. 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 of seafood itself (such as in fresh seafood). Summary of the invention

[0003] In view of the gap in radiation detection of seafood in the current radiation measurement field, the present application provides a probe-type seafood radiation measuring instrument that can measure the radiation dose deeply inside the seafood and quickly give the accurate radiation dose in the 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 spring compression, and the other end is fixed by the 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 card slot is designed at the connection between the scintillation optical fiber and the cover to fix the SiPM chip; the SiPM chip is coupled and connected 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 to the SiPM chip inside the scintillation optical fiber; the SiPM chip converts the optical signal into an electric current signal and transmits it to the signal processing system; the signal processing system amplifies, filters, calculates and analyzes the electric current signal to obtain the corresponding radiation dose, and displays it through the display module.

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

[0009] Optionally, the scintillation optical fiber is in a cubic shape; 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 cubic scintillation optical fiber are supported by the four protrusions.

[0010] Optionally, a reflective layer is provided on the outer surface of the scintillation 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 determines the radiation dose according to the counting rate.

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

[0016] Optionally, 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.

[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 respectively connected to the temperature sensor and the SiPM chip;

[0018] The temperature sensor is packaged together with the SiPM chip, and is used to measure the ambient temperature of the SiPM chip and send it to the temperature compensation circuit; the temperature compensation circuit determines the voltage adjustment amount according to the ambient temperature change of 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.

[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, which sets a spring and a protrusion in the internal cavity of a stainless steel needle tube, so that the scintillating optical fiber remains stationary and stable and in stable contact with the SiPM chip; a card slot is designed at the connection between the scintillator and the cover to fix the SiPM chip, which further deepens the coupling degree between the scintillating optical fiber and the SiPM chip, and improves the detection efficiency and detection accuracy; by using stainless steel as the light-shielding material of the measuring probe shell, it takes into account the material strength, high corrosion resistance and most importantly food safety, and also avoids the influence of light on the operation of the scintillating optical fiber, further improving the detection accuracy. In the seafood radiation measurement scenario, by inserting the measuring probe into the inside of the seafood, you can see the measured radiation dose on the display module after a while, which has the advantages of easy carrying, simple use method, and 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 drawings required for use in the embodiments will be briefly introduced below. 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 paying creative work.

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

[0023] Figure 2 is a 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 the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work 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, with the advantages of portability and reliable measurement results.

[0029] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with 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 , a probe-type seafood radiation measuring instrument provided in an embodiment of the present application includes: a measuring probe, a signal processing system, a display module and a housing 10. The measuring probe includes a stainless steel needle tip 1, a spring 2, a scintillating optical fiber 3, a SiPM chip 4, a cover 5, a protruding portion 6 and a stainless steel needle tube 7. The display module includes a button 8 and a display screen 9 embedded in the surface of the housing 10. The signal processing system is integrated inside the housing 10. The button 8 is connected to the single-chip microcomputer in the signal processing system to control the switch 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 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 7 and enter the scintillation optical fiber 3, so that the scintillation optical fiber 3 generates an optical signal. The optical signal is transmitted to the SiPM chip 4 inside the scintillation optical fiber 3. The SiPM chip 4 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 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 in a cubic shape, one end of which contacts the spring 2 and the other end contacts the SiPM chip 4. The present application adds a spring 2 inside the cavity of the stainless steel needle tube 7 where the scintillator 3 is placed, so that the spring 2 can help the scintillator 3 to stably contact the SiPM chip 4.

[0034] Furthermore, considering that the scintillator 3 is relatively 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 convex part 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 in a structure of two opposing each other in the cylindrical cavity of the stainless steel needle tube 7, that is, 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 slot at the connection between the scintillator 3 and the cover 5 to fix the SiPM chip 4, so as to deepen the coupling degree between the scintillator 3 and the SiPM chip 4 and improve the detection efficiency.

[0037] The cover 5 is used to seal the top of the measuring probe. Since the scintillation optical fiber 3 needs to be coupled with the SiPM chip 4, the measuring probe adopts a hollow structure except for the stainless steel needle tip 1. The SiPM chip 4 is embedded in the card slot on the cover 5. The cover 5 and the top of the measuring probe are designed to be a separable and mutually interlocking structure similar to building blocks. Similarly, the stainless steel needle tip 1 and the stainless steel needle tube 7 can also be designed to be a separable and mutually interlocking structure.

[0038] In some preferred embodiments, optical coupling glue can be used to assist coupling between the scintillating optical fiber 3 and the SiPM chip 4. The optical coupling glue 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 measuring probe as a sleeve structure.

[0040] Taking into account the requirements of the usage scenario, the material of the measuring probe 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 the light signal will have certain loss when propagating in the scintillator 3, the present application adds a reflective layer outside the scintillator 3 to increase the reflectivity of light and reduce the loss of the light signal. This can be achieved by wrapping the outer surface of the scintillator 3 with aluminum foil or tin foil.

[0042] At present, conventional radiation measuring instruments available on the market are all gamma dose rate meters. Generally, gamma dose rate meters use gas detectors as radiation sensors. Gas detectors have low gamma ray detection efficiency and poor energy response. They have no major problems with strong radiation environment measurements, but have shortcomings such as long response time and large statistical errors for weak radiation measurements, and cannot provide accurate results. In this regard, the present application uses a high-density lutetium oxide scintillating fiber 3 as a core component, which can generate a weak light signal under radiation conditions, adds a reflective layer to its outer surface to increase the photon collection rate, and uses a SiPM chip 4 as a photoelectric device to realize photoelectric signal conversion, which can achieve high detection efficiency with a small volume.

[0043] On the other hand, conventional gamma dose rate meters are non-contact measurements. The measuring instrument is generally a certain distance away from the surface of the object and can only measure gamma rays in a certain direction. In addition, due to the self-absorption of gamma rays by the medium, low-energy gamma rays generated inside the object to be measured may not be measured. In this regard, the present application uses a food-grade high-strength stainless steel needle 1 and a stainless steel needle tube 7 to form the outer surface material of the measuring probe, which can be inserted into the interior of the seafood to be tested for radiation measurement, which can ensure light protection and realize contact measurement, greatly improving the 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 (radiation source), it will emit a light signal. After the SiPM chip 4 detects these light signals, it 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 amplifier 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 the filter circuit is used to reduce the signal noise level, convert the analog signal into a digital signal, and optimize the signal readout. 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-R11, capacitors C10-C13, capacitors C15-C16 and an inductor L3. The single-chip microcomputer adopts an 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 respectively 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 end of the operational amplifier U2 is respectively 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 end signal of the operational amplifier U2 is U SiPM . The other end of capacitor C14 is grounded. The positive input end of the operational amplifier U3 is respectively connected to the other end of resistor R8, one end of capacitor C15 and one end of resistor R11. The other end of capacitor C15 is grounded. The reverse input end of the operational amplifier U3 is respectively connected to one end of resistor R9 and one end of resistor R10. The other end of resistor R10 is grounded. The other end of resistor R9 is respectively connected to one end of capacitors C10 to C13 and one end of inductor L3. 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 end of the operational amplifier U3 is respectively connected to the other end of resistor R11 and the input end of the STM32 series microcontroller.

[0046] The amplifying circuit is used to convert the current signal I output by the SiPM chip 4 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 digital signal is converted into a digital signal and subjected to noise reduction filtering. The filtered digital signal is read by the single-chip counter. The program burned into the single-chip microcomputer obtains the counting rate by dividing the number of counter responses by the measurement time, and the radiation dose is determined according to the counting rate. Furthermore, the single-chip microcomputer is also used to determine whether the radiation dose exceeds the standard; if it exceeds the standard, the display screen 9 outputs a radiation exceeding standard prompt.

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

[0048] The high-voltage power supply circuit uses a monolithic integrated switching voltage-stabilized power supply chip U1, which has a wide voltage input range (3-40V) 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, wherein the electrolytic capacitor C4 filters out the low-frequency components, and the ceramic capacitors C5 and C6 are used to filter out the 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 output voltage VOUT2 is 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 to detect the temperature change of the chip environment. 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. This is because the breakdown voltage of the SiPM will change with the change of temperature. Since overvoltage = working voltage - breakdown voltage, if the working 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 the 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 single-chip microcomputer. If the gain changes, more interference signals will be read or the high-energy signals that should be 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 to measure the ambient temperature of the SiPM chip 4 and send it to the temperature compensation circuit. The temperature compensation circuit determines the voltage adjustment amount ΔV according to the ambient temperature change of the SiPM chip 4. The voltage adjustment amount ΔV is input to the SiPM chip 4, so that the initial overvoltage can be maintained constant according to the formula "overvoltage = working voltage - breakdown voltage + voltage adjustment amount ΔV".

[0051] Under this condition, if Figure 3 and Figure 4 As shown in the figure, the amplifier circuit converts the current signal into a voltage signal, amplifies the readout signal, and realizes high-sensitivity light detection; and cooperates with the noise reduction filter circuit to reduce the signal noise level and optimize the signal readout. Finally, the signal is read out by the microcontroller as radiation intensity information and fed back to the user.

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

[0053] The radiation from the radiation source can make the scintillating optical fiber 3 excite more high-energy photons. The high-energy photons hit the SiPM chip 4 to generate a larger photocurrent. The photocurrent is converted into a voltage signal through the amplifier circuit and then amplified and filtered, and can be read by the single-chip counter. The program burned into the single-chip microcomputer obtains the counting rate by dividing the number of counter responses by the measurement time. Further, the single-chip microcomputer can look up the table to determine the corresponding radiation intensity, that is, the radiation dose, according to the pre-calibrated counting rate and radiation intensity comparison table, according to the counting rate. The single-chip microcomputer can also further determine whether the radiation intensity exceeds the standard. If it exceeds the standard, the single-chip microcomputer can be connected to the LED display screen 9 to display and output the words "Radiation exceeds the standard, unqualified" for prompting, or connect a buzzer or other sound and light alarm device to output an alarm signal.

[0054] The present application realizes the radiation measurement of seafood (such as fresh seafood) by providing a probe-type fresh seafood radiation measuring instrument, filling the gap in the radiation detection of seafood in the current radiation measurement field. In the radiation measurement scenario of seafood, by inserting the probe-type fresh seafood radiation measuring instrument 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 measuring instrument of the present application can realize high-precision contact measurement of the radiation dose in the fresh seafood, quickly give the radiation dose in the seafood, and has the advantages of small size, light weight, low price, easy to carry, and reliable measurement results.

[0055] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, 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 this application.

Claims

1. A probe type seafood radiation measuring instrument, characterized in that: include: 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 chip; 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 inner 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 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 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 and connected to the other end of the scintillation optical 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 to the SiPM chip inside the scintillation optical fiber; the SiPM chip converts the optical signal into an electric current signal and transmits it to the signal processing system; the signal processing system amplifies, filters, calculates and analyzes the electric current signal to obtain the corresponding radiation dose, and displays it through the display module.

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

3. The probe type seafood radiation measuring instrument according to claim 1, characterized in that: The scintillation optical fiber is in a cubic shape; the protrusion in the inner cavity of the stainless steel needle tube includes four protrusions, which are in a structure opposed to each other. The other end of the scintillation optical fiber is placed in the middle of the four protrusions, and the four sides of the cubic scintillation optical fiber are supported by the four protrusions.

4. The probe type seafood radiation measuring instrument according to claim 1, characterized in that: The outer surface of the scintillation optical fiber is provided with a reflection layer.

5. The probe type seafood radiation measuring instrument according to claim 1, characterized in that: Optical coupling glue is used to assist coupling between the scintillating optical fiber and the SiPM chip.

6. The probe type marine product radiation measuring instrument according to claim 1, characterized in that: 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.

7. The probe type marine product radiation measuring instrument according to claim 1, characterized in that: The signal processing system comprises: 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 determines the radiation dose according to the counting rate.

8. The probe type marine product radiation measuring instrument according to claim 7, 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.

9. The probe type marine product radiation measuring instrument according to claim 7, characterized in that: The display module also 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 measuring instrument.

10. The probe type marine product radiation measuring instrument according to claim 1, characterized in that: 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 respectively connected to the temperature sensor and the SiPM chip; The temperature sensor is packaged together with the SiPM chip, and is used to measure the ambient temperature of the SiPM chip and send it to the temperature compensation circuit; the temperature compensation circuit determines the voltage adjustment amount according to the ambient temperature change of 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.

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