CN104678423B - The measuring method of dose equivalent under the conditions of binary channels number system and high dose - Google Patents

Abstract

The invention relates to the technical field of ionizing radiation testing, and provides a dual-channel counting system and a method for measuring dose equivalent under high dose conditions to solve the problem of measuring dose equivalent under high dose conditions. The measurement method mainly includes: initializing a dual-channel counting system; performing measurements in a medium-energy radiation field and a high-energy radiation field respectively; performing linear fitting on the measured values under each condition to obtain an interpolation equation. The technical scheme proposed by the invention realizes simultaneous correction of the counting linearity and energy response of the semiconductor detector within a certain range of average effective energy of the radiation field.

Description

Double-channel counting system and measurement method of dose equivalent under high-dose conditions

technical field

The invention relates to the technical field of ionizing radiation testing, in particular to a dual-channel counting system and a method for measuring dose equivalent under high dose conditions.

Background technique

Due to the characteristics of low power consumption, small size, high sensitivity, and real-time measurement, semiconductor personal dosimeters are widely used in radiation sites such as nuclear power plants, radiology, non-destructive detection, and reactors. The development of nuclear power will further intensify the demand for personal dosimeters along with the increasing demand for energy. However, due to the constraints of instrument power consumption, volume, and detector front-end technology, the detector electronic system composed of low-power consumption and arrayed components has a certain width of the output nuclear pulse signal. When it is in a high-dose radiation field, it will Pulse pile-up occurs, resulting in poor counting linearity.

In order to solve the above problems, there are two main methods currently adopted. The first one is under the single energy condition, the counting linear correction can be completed through the dead time correction technology, but the dead time correction coefficient is different under different energies. In the actual measurement The energy characteristics of rays in the middle radiation field are often unclear, so the dose measurement under the condition of high dose with the average effective energy in the range of 48keV～1.25MeV cannot be realized. In addition, semiconductor chip integration technology can be used to replace the front-end detector electronics system composed of arrayed components, and the non-linear problem of counting can be solved by increasing the output width of the pulse signal without losing sensitivity. The method is restricted by semiconductor chip integration technology, and the cost is relatively high.

This invention is a project funded by the special fund for the development of major national scientific instruments and equipment (project name: development and application of new ionizing radiation detection instruments and key components, project number: 2013YQ090811).

Contents of the invention

【Technical problems to be solved】

The purpose of the present invention is to provide a dual-channel counting system and a method for measuring dose equivalent under high dose conditions to solve the problem of measuring dose equivalent under high dose conditions with average effective energy in the radiation field within the range of 48keV-1.25MeV.

【Technical solutions】

The present invention is achieved through the following technical solutions.

The present invention firstly relates to a dual-channel counting system, which includes a semiconductor detector, a charge-sensitive amplifier circuit, a first pulse shaping circuit, a first comparator, a second pulse shaping circuit, a second comparator, and an MCU. The pulse shaping circuit and the second pulse shaping circuit are respectively configured to output pulse signals of different amplitudes and widths, and the MCU includes a first counter for counting the output pulses of the first comparator, and a counter for counting the output pulses of the second comparator. A second counter that outputs pulses for counting,

The input end of the charge-sensitive amplifying circuit is connected with the semiconductor detector, and its output end is respectively connected with the input end of the first pulse shaping circuit and the input end of the second pulse shaping circuit; the input end of the first comparator is connected with the input end of the second pulse shaping circuit respectively; The output end of the first pulse shaping circuit is connected to the first threshold voltage signal source, the input end of the second comparator is respectively connected to the output end of the second pulse shaping circuit and the second threshold voltage signal source, and the first threshold The voltage value of the signal source is not equal to the voltage value of the second threshold signal source; the MCU is respectively connected to the output terminal of the first comparator and the output terminal of the second comparator.

As a preferred embodiment, the charge-sensitive amplifying circuit includes a JFET, a first resistor, a second resistor, a first capacitor, and a first operational amplifier, and the gate of the JFET is used as an input terminal of the charge-sensitive amplifying circuit to communicate with the The anode of the semiconductor detector, one end of the second resistor, and one end of the first capacitor are connected, the source of the JFET is grounded, and the drain of the JFET is respectively connected with one end of the first resistor and the input end of the first operational amplifier, The cathode of the semiconductor detector and the other end of the first resistor are all connected to the first voltage source, and the output end of the first operational amplifier is respectively connected to the other end of the second resistor and the first voltage source as the output end of the charge sensitive amplifier circuit. The other end of the capacitor is connected.

As another preferred implementation manner, the ratio of the voltage value of the first threshold voltage signal source to the voltage value of the second threshold voltage signal source is less than or equal to 0.8.

As another preferred implementation manner, the semiconductor detector is a Si-Pin detector.

The present invention also relates to a method for measuring dose equivalent under high-dose conditions, the method comprising:

Step A: Initialize the dual-channel counting system described in any one of the above-mentioned embodiments;

Step B: selecting a radiation field, the radiation field is a medium-energy radiation field or a high-energy radiation field;

Step C: Determine the measurement conditions. If the selected radiation field is a medium-energy radiation field, the measurement condition is the tube current of the radiation source; if the selected radiation field is a high-energy radiation field, the measurement condition is the dose equivalent measurement position ;

Step D: Under the determined measurement conditions, use the dual-channel counting system to count the radiation dose of the radiation source, and perform weighting processing on the _first counter count value N1 and the second counter count value _N2 to obtain a dual-channel The count value M ₁ , the formula of the weighting process is:

In the above formula, the value of A is or B is the time unit conversion factor;

Step E: Under the determined measurement conditions, use the standard measuring instrument to measure the measured value D ₂ of the standard measuring instrument, and convert the measured value D ₂ of the standard measuring instrument to obtain the converted value M ₂ of the standard measuring instrument. The formula for processing is:

M ₂ =D ₂ ·L·H,

In the above formula, L is the sensitivity factor under the ¹³⁷ Cs radiation field, and H is the dose unit conversion factor;

Step F: Calculating the ratio K _r between the converted value M ₂ of the standard meter and the count value M ₁ of the two channels;

Step G: Re-determine the measurement conditions, repeat steps D to F to obtain the dual-channel count value M ₁ under different measurement conditions, the measurement value D ₂ of the standard meter, and the ratio K _r , and calculate the dual-channel count value under each measurement condition The value M ₁ , the reciprocal of the ratio K _r , the measured value D ₂ of the standard measuring instrument, and the ratio K _r are respectively stored in the first vector, the second vector, the third vector and the fourth vector;

Step H: performing linear fitting on the data of the first vector and the data of the second vector to obtain the first linear equation, and performing linear fitting on the data of the third vector and the data of the fourth vector to obtain the second linear equation;

Step I: Repeat Step B to Step H until the measurement of the medium-energy radiation field and the high-energy radiation field is completed, specifically, if the radiation field selected in step B is a medium-energy radiation field, then adjust the tube voltage of the radiation source of the medium-energy radiation field, Repeat steps C to H to obtain the first line equation and the second line equation of the medium-energy radiation field under various tube voltage conditions. If the radiation field selected in step B is a high-energy radiation field, then perform steps C to H to obtain The first straight line equation and the second straight line equation under the high energy radiation field;

Step J: Combine all the first line equations into the first set of line equations, combine all the second line equations into the second set of line equations, and in the first set of line equations, the line equation with the largest slope and The linear equation with the smallest slope is interpolated to obtain the first interpolation equation, and the linear equation with the largest slope and the linear equation with the smallest slope are interpolated in the second set of linear equations to obtain the second interpolation equation;

Step K: Correct the dual-channel count value M ₁ by using the first interpolation equation and the second interpolation equation.

As a preferred embodiment, the step K specifically includes:

Step K1: _Substituting the dual-channel count value M1 into the _first interpolation equation for solution to obtain the reciprocal of the ratio Kr;

Step K2: Substitute the ratio K _r obtained in step K1 into the second interpolation equation to obtain the corrected dose equivalent value.

As another preferred embodiment, the medium-energy radiation field is an X-ray radiation field.

As another preferred embodiment, the tube voltage value of the X-ray radiation field is 100kV, 150kV, 200kV, 250kV or 300kV.

As another preferred embodiment, the high-energy radiation field is a ⁶⁰ Co radiation field.

As another preferred embodiment, the average effective energy of the radiation field in the step B ranges from 48keV to 1.25MeV, and the adjustable dose equivalent value ranges from 50mSv/h to 1Sv/h.

【Beneficial effect】

The technical scheme proposed by the present invention has the following beneficial effects:

(1) The present invention adopts ultra-low power consumption sorting components and integrates Si-PIN detectors, which has the advantages of low hardware cost, simple structure, and convenient mass production. It conforms to my country's national conditions and can partially replace foreign related instruments, improving economic benefits;

(2) The present invention uses different pulse shaping parameters and threshold settings to form a counting system with inconsistent counting responses of the two channels. Through the analysis of a large number of experimental data, using calculation methods such as empirical formulas and interpolation operations, to find out the accurate measurement method under the high-dose conditions of different energies and high-dose conditions, the same equation group can be used to complete the high-dose conditions, so the method of the present invention has great advantages in practical applications. Convenient and fast features;

(3) Because the single-channel counting method in the prior art needs to correct the counting of the system through the dead time at known ray energy, and finally multiply the dose correction factor under the condition of known ray energy to complete the dose measurement. However, in actual measurement, the energy characteristics of the ray whose average effective energy in the radiation field is 48keV～1.25Mev cannot be known through the single-channel counting method. Accurate measurement of dose, taking into account the simultaneous correction of semiconductor detector count linearity and energy response.

Description of drawings

Fig. 1 is the structural block diagram of the dual-channel counting system provided by Embodiment 1 of the present invention;

FIG. 2 is a schematic circuit diagram of a dual-channel counting system provided by Embodiment 1 of the present invention.

detailed description

In order to make the purpose, technical solutions and advantages of the present invention clearer, the specific implementation manners of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are part of the embodiments of the present invention, rather than All examples are not limitations of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Figure 1 is a structural block diagram of a dual-channel counting system for dose equivalents under high-dose conditions provided by Embodiment 1 of the present invention, and Figure 2 is a schematic circuit diagram of a dual-channel counting system for dose equivalents under high-dose conditions provided by Embodiment 1 of the present invention . As shown in Figure 1 and Figure 2, the system includes a semiconductor detector D1, a charge-sensitive amplifier circuit, a first pulse shaping circuit, a first comparator U4, a second pulse shaping circuit, a second comparator U5, and an MCUU6, wherein the first A pulse shaping circuit and a second pulse shaping circuit are respectively configured to output pulse signals of different amplitudes and widths. pulses to count the second counter.

In Embodiment 1, the input end of the charge-sensitive amplifier circuit is connected to the semiconductor detector D1, and its output end is respectively connected to the input end of the first pulse shaping circuit and the input end of the second pulse shaping circuit; the input end of the first comparator U4 Terminal a is connected to the output terminal of the first pulse shaping circuit, the input terminal b of the first comparator U4 is connected to the first threshold voltage signal source, and the input terminal c of the second comparator U5 is connected to the output terminal of the second pulse shaping circuit , the input terminal d of the second comparator U5 is connected to the second threshold voltage signal source, the voltage value of the first threshold signal source is not equal to the voltage value of the second threshold signal source, specifically, the voltage of the first threshold voltage signal source The ratio of the value to the voltage value of the second threshold voltage signal source is equal to 0.75; the MCU is respectively connected to the output terminal of the first comparator U4 and the output terminal of the second comparator U5.

In the first embodiment, the charge-sensitive amplifying circuit includes JFETQ1, resistor R1, resistor R10, capacitor C1 and operational amplifier U1, and the gate of JFETQ1 is connected with the anode of semiconductor detector D1 and one end of resistor R1 respectively as the input end of the charge-sensitive amplifying circuit. , one end of capacitor C1 is connected, the source of JFETQ1 is grounded to GND, the drain of JFETQ1 is respectively connected to one end of resistor R10 and the input end of operational amplifier U1, the cathode of semiconductor detector D1, and the other end of resistor R10 are connected to voltage source VCC The output terminal of the operational amplifier U1 is used as the output terminal of the charge sensitive amplifier circuit to be respectively connected to the other end of the resistor R1 and the other end of the capacitor C1.

In Embodiment 1, the first pulse shaping circuit includes a resistor R2, a resistor R3, a resistor R4, a resistor R5, a capacitor C2, a capacitor C3, and an operational amplifier U2. One end of the resistor R2 is used as the input end of the first pulse shaping circuit, and the other end is respectively connected with one end of the capacitor C2 and one end of the resistor R3; the other end of the resistor R3 is respectively connected with one end of the capacitor C3 and the non-inverting input end of the operational amplifier U2 The other end of the capacitor C3 is grounded to GND; the inverting input terminal of the operational amplifier U2 is connected to one end of the resistor R4 and one end of the resistor R5 respectively; the other end of the resistor R4 is grounded to GND; the output terminal of the operational amplifier U2 is used as the first pulse shaping circuit The output terminals of the resistor R5 are respectively connected to the other end of the resistor R5 and the other end of the capacitor C2.

In Embodiment 1, the second pulse shaping circuit includes a resistor R6, a resistor R7, a resistor R8, a resistor R9, a capacitor C4, a capacitor C5, and an operational amplifier U3. One end of the resistor R6 is used as the input end of the second pulse shaping circuit, and the other end is respectively connected with one end of the capacitor C4 and one end of the resistor R7; the other end of the resistor R7 is respectively connected with one end of the capacitor C5 and the non-inverting input end of the operational amplifier U3 The other end of the capacitor C5 is grounded to GND; the inverting input terminal of the operational amplifier U3 is connected to one end of the resistor R8 and one end of the resistor R9 respectively; the other end of the resistor R8 is grounded to GND; the output terminal of the operational amplifier U3 is used as the first pulse shaping circuit The output terminals of the resistor R9 are respectively connected to the other end of the resistor R9 and the other end of the capacitor C4.

For the method of measuring dose equivalent under high dose conditions using the dual-channel counting system provided in Example 1, reference may be made to the following specific method examples.

Embodiment 2 provides a method for measuring dose equivalent under high-dose conditions, the method comprising:

Step 1: Initialize the dual-channel counting system.

Specifically, the dual-channel counting system provided in Embodiment 1 is initialized. Configure the first pulse shaping circuit and the second pulse shaping circuit so that the first pulse shaping circuit and the second pulse shaping circuit output pulse signals with different amplitudes and widths; configure the first threshold voltage signal source and the second threshold voltage signal source so that The ratio of the voltage value of the first threshold voltage signal source to the voltage value of the second threshold voltage signal source is equal to 0.75.

Step 2: Select the X-ray radiation field as the medium-energy radiation field, and set the tube voltage of the X-ray radiation field. Specifically, the tube voltage value of the X-ray radiation field is 100 kV, 150 kV, 200 kV, 250 kV or 300 kV. It should be noted that in this embodiment, the average effective energy of the radiation field ranges from 48keV to 1.25MeV, and the dose equivalent value can be adjusted from 50mSv/h to 1Sv/h.

Step 3: setting the tube current of the X-ray radiation field. Under each tube voltage value, the dose equivalent value is adjusted by changing the tube current. It should be noted that the dose equivalent value adjustment range is 50mSv/h～1Sv/h.

Step 4: Use a dual-channel counting system to count the radiation dose of the radiation source, and perform weighting processing on the first counter count value N ₁ and the second counter count value N ₂ to obtain a dual-channel count value M ₁ , wherein the formula for weighting processing for:

In the above formula, the value of A is B is the time unit conversion factor, which is used to unify the time unit into hours.

Step 5: Under the same measurement conditions as Step 4, use a standard meter to measure the measured value D ₂ of the standard meter, and convert the measured value D ₂ of the standard meter to obtain the converted value M ₂ of the standard meter. The formula for the conversion process is:

M ₂ =D ₂ ·L·H,

In the above formula, L is the sensitivity factor under the ¹³⁷ Cs radiation field, which means that under the ¹³⁷ Cs radiation condition, the ratio of the double-channel count value per hour of the dual-channel counting system to the measured value of the standard meter, specifically, this embodiment In the radiation protection standard laboratory, ¹³⁷ Cs is used for gamma sensitivity measurement, and the sensitivity factor L is 214.3; H is the dose unit conversion factor, which is used to convert mSv to μSv, because the unit of the measurement value of the standard meter is is mSv, so the value of H in this embodiment is 1000.

Step 6: Calculate the ratio K _r between the converted value M ₂ of the standard meter and the count value M ₁ of the two channels;

Step 7: Reset the tube current of the X-ray radiation field, repeat steps 4 to 6, and obtain the dual-channel count value M ₁ , the measured value D ₂ of the standard meter, and the ratio K _r under different tube current conditions, and convert each measurement Under the conditions, the dual-channel count value M ₁ , the reciprocal of the ratio K _r , the measured value D ₂ of the standard meter, and the ratio K _r are respectively stored in the first vector, the second vector, the third vector and the fourth vector;

Step 8: Perform linear fitting on the data of the first vector and the data of the second vector in step 7 to obtain the first line equation, and perform linear fitting on the data of the third vector and the data of the fourth vector to obtain the second line equation .

Step 9: Repeat steps 2 to 8 until the first linear equation and the second linear equation of the X-ray radiation field under various tube voltage conditions are completed.

Step 10: Select ⁶⁰ Co radiation field as the high-energy radiation field. It should be noted that in this embodiment, the average effective energy of the radiation field ranges from 48keV to 1.25MeV, and the dose equivalent value can be adjusted from 50mSv/h to 1Sv/h.

Step 11: Determine the dose equivalent measurement position, that is, determine the position in the radiation field for measurement. This step is used to adjust the dose equivalent value. Specifically, the adjustment of the dose equivalent value can be realized by changing the measuring distance of the instrument. It should be noted that the dose equivalent value adjustment range is 50mSv/h～1Sv/h.

Step 12: Use a dual-channel counting system to count the radiation dose of the radiation source, and perform weighted processing on the first counter count value N ₁ and the second counter count value N ₂ to obtain a dual-channel count value M ₁ , where the weighted The formula is:

In the above formula, the value of A is B is the time unit conversion factor, which is used to unify the time unit into hours.

Step 13: Under the same measurement conditions as Step 12, use a standard meter to measure the measured value D ₂ of the standard meter, and convert the measured value D ₂ of the standard meter to obtain the converted value M of the standard meter _2. The formula for the conversion process is:

M ₂ =D ₂ ·L·H,

In the above formula, L is the sensitivity factor under the ¹³⁷ Cs radiation field, which means that under the ¹³⁷ Cs radiation condition, the ratio of the double-channel count value per hour of the dual-channel counting system to the measured value of the standard meter, specifically, this embodiment In the radiation protection standard laboratory, ¹³⁷ Cs is used for gamma sensitivity measurement, and the sensitivity factor L is 214.3; H is the dose unit conversion factor, which is used to convert mSv to μSv. The unit is mSv, so the value of H in this embodiment is 1000.

Step 14: Reset the dose equivalent measurement position, repeat steps 12 to 13 to obtain the dual-channel count value M ₁ , the measurement value D ₂ of the standard meter, and the ratio K _r at different dose equivalent measurement positions, and set The dual-channel count value M ₁ , the reciprocal of the ratio K _r under each measurement condition, the measured value D ₂ of the standard meter, and the ratio K _r are stored in the first vector, the second vector, the third vector and the fourth vector respectively.

Step 15: Perform linear fitting on the data of the first vector and the data of the second vector in step 14 to obtain the first line equation, and perform linear fitting on the data of the third vector and the data of the fourth vector to obtain the second straight line equation.

Step 16: combine all the first line equations obtained in step 9 and step 15 into the first set of line equations, and combine all the second line equations obtained in step 9 and step 15 into the second set A set of straight line equations. In the first set of straight line equations, interpolation is performed on the straight line equation with the largest slope and the straight line equation with the smallest slope to obtain the first interpolation equation. In the second set of straight line equations, the straight line equation with the largest slope and the smallest slope are interpolated. The linear equation is interpolated to obtain the second interpolation equation.

The specific interpolation method will be briefly described below. Let the equation of the straight line with the largest slope be:

y=a ₁ x+b ₁ , where a ₁ and b ₁ are constants,

The equation of the straight line with the smallest slope is:

y=a ₂ x+b ₂ , where a ₂ and b ₂ are constants,

Then the interpolation equation obtained by interpolation is: y=(a ₁ +a ₂ )x/2+(b ₁ +b ₂ )/2.

Step seventeen: Correct the dual-channel count value M ₁ by using the first interpolation equation and the second interpolation equation.

Specifically, assuming that the first interpolation equation is: y=-2.6029e- ⁸ x+1.1098, the second interpolation equation is: y=0.00494875x+1.047755, and the dual-channel count value M ₁ is substituted into the first interpolation equation as the x variable, The y variable obtained from the solution is the reciprocal of the ratio K _r , and the reciprocal of y obtained from the solution is used as the y variable to be substituted into the second interpolation equation, and the value of the x variable obtained from the solution is the corrected dose equivalent value.

It should be noted that in Embodiment 2, steps 2 to 9 are the medium-energy measurement part, and steps 10 to 15 are the high-energy measurement part. This embodiment does not limit the execution order of the medium-energy measurement part and the high-energy measurement part, that is, High-energy measurements can be performed first, followed by medium-energy measurements.

As can be seen from the above examples:

The embodiment of the present invention adopts ultra-low power consumption components and integrates Si-PIN detectors, which has the advantages of low hardware cost, simple structure, and convenient mass production. benefit;

The embodiment of the present invention uses different pulse shaping parameters and threshold settings to form a counting system with inconsistent counting responses of the two channels. Through the analysis of a large number of experimental data, using calculation methods such as empirical formulas and interpolation operations, to find out the accurate measurement method under the high-dose conditions of different energies and high-dose conditions, the same equation group can be used to complete the high-dose conditions, so the method of the present invention has great advantages in practical applications. Convenient and fast features;

Because the single-channel counting method in the prior art needs to correct the counting of the system through the dead time at known ray energy, and finally multiply the dose correction factor under the condition of known ray energy to complete the dose measurement. However, in actual measurement, the energy characteristics of the ray whose average effective energy in the radiation field is 48keV-1.25Mev cannot be known through the single-channel counting method. The embodiment of the present invention overcomes the shortcomings of the single-channel counting method in high-dose measurement. Accurate measurement of high dose is achieved, taking into account the simultaneous correction of semiconductor detector count linearity and energy response.

Claims (9)

1. A dual-channel counting system is characterized in that: it comprises a semiconductor detector, a charge-sensitive amplifier circuit, a first pulse shaping circuit, a first comparator, a second pulse shaping circuit, a second comparator, an MCU, and the The first pulse shaping circuit and the second pulse shaping circuit are respectively configured to output pulse signals of different amplitudes and widths, the MCU includes a first counter for counting the output pulses of the first comparator, and a second counter for comparing The output pulses of the tor are counted by the second counter, The input end of the charge-sensitive amplifying circuit is connected with the semiconductor detector, and its output end is respectively connected with the input end of the first pulse shaping circuit and the input end of the second pulse shaping circuit; the input end of the first comparator is connected with the input end of the second pulse shaping circuit respectively; The output end of the first pulse shaping circuit is connected to the first threshold voltage signal source, the input end of the second comparator is respectively connected to the output end of the second pulse shaping circuit and the second threshold voltage signal source, and the first threshold The voltage value of the signal source is not equal to the voltage value of the second threshold signal source; the MCU is respectively connected to the output terminal of the first comparator and the output terminal of the second comparator. 2. The dual-channel counting system according to claim 1, wherein the charge-sensitive amplifier circuit comprises a JFET, a first resistor, a second resistor, a first capacitor and a first operational amplifier, and the gate of the JFET serves as The input end of the charge-sensitive amplifying circuit is respectively connected to the anode of the semiconductor detector, one end of the second resistor, and one end of the first capacitor, the source of the JFET is grounded, and the drain of the JFET is respectively connected to one end of the first resistor, The input terminal of the first operational amplifier is connected, the cathode of the semiconductor detector and the other end of the first resistor are connected with the first voltage source, and the output terminal of the first operational amplifier is respectively connected with the output terminal of the charge sensitive amplifier circuit The other end of the second resistor is connected to the other end of the first capacitor. 3. The dual-channel counting system according to claim 1 or 2, characterized in that the ratio of the voltage value of the first threshold voltage signal source to the voltage value of the second threshold voltage signal source is less than or equal to 0.8. 4. The dual-channel counting system according to claim 1, characterized in that the semiconductor detector is a Si-Pin detector. 5. A method for measuring dose equivalent under high-dose conditions, characterized in that it comprises: Step A: initializing the dual-channel counting system described in any one of claims 1 to 4; Step B: selecting a radiation field, the radiation field is a medium-energy radiation field or a high-energy radiation field; Step C: Determine the measurement conditions. If the selected radiation field is a medium-energy radiation field, the measurement condition is the tube current of the radiation source; if the selected radiation field is a high-energy radiation field, the measurement condition is the dose equivalent measurement position ; Step D: Under the determined measurement conditions, use the dual-channel counting system to count the radiation dose of the radiation source, and perform weighting processing on the _first counter count value N1 and the second counter count value _N2 to obtain a dual-channel The count value M ₁ , the formula of the weighting process is: ${\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; A</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; B</span>}<span\; class="notranslate">\; ,</span>$ In the above formula, the value of A is or B is the time unit conversion factor; Step E: Under the determined measurement conditions, use the standard measuring instrument to measure the measured value D ₂ of the standard measuring instrument, and convert the measured value D ₂ of the standard measuring instrument to obtain the converted value M ₂ of the standard measuring instrument. The formula for processing is: M ₂ =D ₂ ·L·H, In the above formula, L is the sensitivity factor under the ¹³⁷ Cs radiation field, and H is the dose unit conversion factor; Step F: Calculating the ratio K _r between the converted value M ₂ of the standard meter and the count value M ₁ of the two channels; Step G: Re-determine the measurement conditions, repeat steps D to F to obtain the dual-channel count value M ₁ under different measurement conditions, the measurement value D ₂ of the standard meter, and the ratio K _r , and calculate the dual-channel count value under each measurement condition The value M ₁ , the reciprocal of the ratio K _r , the measured value D ₂ of the standard measuring instrument, and the ratio K _r are respectively stored in the first vector, the second vector, the third vector and the fourth vector; Step H: performing linear fitting on the data of the first vector and the data of the second vector to obtain the first linear equation, and performing linear fitting on the data of the third vector and the data of the fourth vector to obtain the second linear equation; Step I: Repeat Step B to Step H until the measurement of the medium-energy radiation field and the high-energy radiation field is completed, specifically, if the radiation field selected in step B is a medium-energy radiation field, then adjust the tube voltage of the radiation source of the medium-energy radiation field, Repeat steps C to H to obtain the first line equation and the second line equation of the medium-energy radiation field under various tube voltage conditions. If the radiation field selected in step B is a high-energy radiation field, then perform steps C to H to obtain The first straight line equation and the second straight line equation under the high energy radiation field; Step J: Combine all the first line equations into the first set of line equations, combine all the second line equations into the second set of line equations, and in the first set of line equations, the line equation with the largest slope and The linear equation with the smallest slope is interpolated to obtain the first interpolation equation, and the linear equation with the largest slope and the linear equation with the smallest slope are interpolated in the second set of linear equations to obtain the second interpolation equation; Step K: using the first interpolation equation and the second interpolation equation to correct the dual _- channel count value M1, Described step K specifically comprises: Step K1: _Substituting the dual-channel count value M1 into the _first interpolation equation for solution to obtain the reciprocal of the ratio Kr; Step K2: Substitute the ratio K _r obtained in step K1 into the second interpolation equation to obtain the corrected dose equivalent value. 6. The method for measuring dose equivalent under high-dose conditions according to claim 5, characterized in that the medium-energy radiation field is an X-ray radiation field. 7. The method for measuring dose equivalent under high dose conditions according to claim 6, characterized in that the tube voltage value of the X-ray radiation field is 100kV, 150kV, 200kV, 250kV or 300kV. 8. The method for measuring dose equivalent under high-dose conditions according to claim 5, characterized in that the high-energy radiation field is ⁶⁰ Co radiation field. 9. The method for measuring dose equivalent under high dose conditions according to claim 5, characterized in that the range of the average effective energy of the radiation field in the step B is 48keV～1.25MeV, and the adjustable range of dose equivalent value is 50mSv /h～1Sv/h.