SIPM dose rate detector based on amplification circuit

Abstract

The utility model particularly relates to an SIPM dose rate detector based on an amplifying circuit. The SIPM dose rate detector comprises a scintillator and SIPM coupling module, a pulse shaping circuit and a data receiving and displaying module. A signal amplification circuit and a voltage comparison circuit are arranged between the pulse shaping circuit and the data receiving and displaying module; the scintillator and SIPM coupling module is used for receiving input radiation energy; the pulse shaping circuit is in signal transmission connection with the output end of the scintillator and SIPM coupling module and is used for receiving signals output by the scintillator and SIPM coupling module; the signal amplification circuit is in signal transmission connection with the output end of the pulse shaping circuit and is used for receiving a signal output by the pulse shaping circuit; the voltage comparison circuit is in signal transmission connection with the output end of the signal amplification circuit and is used for receiving a signal output by the signal amplification circuit; the output end of the voltage comparison circuit is in signal transmission connection with the data receiving and displaying module. The structural design of the SIPM dose rate detector is helpful for improving the sensitivity of the SIPM dose rate detector.

Description

TECHNICAL FIELD

[0001] The utility model relates to SIPM detector technical field, concretely relates to a SIPM dose rate detector based on amplification circuit. BACKGROUND

[0002] In the field of radiation protection and monitoring, dose rate detectors are important tools for measuring the intensity of radioactive radiation in the environment. In recent years, with the development of technology, especially the progress of photoelectric detection technology, dose rate detectors based on silicon photo-multipliers (SIPM) have gradually become mainstream. SIPM is a new type of photoelectric detector, which has many advantages compared to traditional photo-multiplier tubes (PMT).

[0003] SIPM is a solid-state device based on avalanche multiplication effect, which can work at a lower voltage and has high sensitivity and magnetic resistance. SIPM is small in size, light in weight, easy to integrate and portable, making it an ideal choice for dose rate detectors. The detection principle of SIPM is to use multiple small Geiger-mode avalanche photodiodes (GM-APDs) to generate electrical signals under light irradiation. When radiation photons (such as X-rays and gamma rays) hit the scintillator (such as CsI(Tl)), the scintillator will emit visible light photons, which are received by the GM-APDs in the SIPM and converted into electrical signals. Each GM-APD can work independently, and when a photon arrives, an avalanche multiplication effect occurs inside, generating an amplified electrical signal. SIPM outputs the total electrical signal by superimposing these signals, achieving the measurement of radiation dose.

[0004] The existing SIPM dose rate detector generally includes a scintillator and SIPM coupling module, a pulse shaping circuit, and a data receiving and display module. The scintillator and SIPM coupling module is used to receive input radiation energy and generate corresponding optical signals, and then convert the optical signals into electrical signals; the pulse shaping circuit is used to receive the electrical signals output by the scintillator and SIPM coupling module and output voltage pulse signals; the data receiving and display module is used to process the voltage pulse signals, generate and display, and store radiation dose data. However, the voltage pulse signal output by the pulse shaping circuit is relatively weak, generally only a few millivolts to tens of millivolts, which is easy to be distorted or lost due to attenuation during transmission, thereby reducing the sensitivity of the SIPM dose rate detector. Therefore, it is necessary to amplify the voltage pulse signal through an amplification circuit. However, how to design an amplification circuit in the existing SIPM dose rate detector is a technical problem that needs to be solved. UTILITY MODEL CONTENT

[0005] The utility model provides to solve the technical problem that the prior art is short of the following: how to provide a SIPM dose rate detector based on amplification circuit, signal amplification circuit and voltage comparison circuit are arranged between pulse shaping circuit and data receiving display module, and the sensitivity of the SIPM dose rate detector is improved through structural design.

[0006] To solve the above technical problems, the utility model adopts the following technical scheme:

[0007] A SIPM dose rate detector based on amplification circuit, including scintillator and SIPM coupling module, pulse shaping circuit and data receiving display module, signal amplification circuit and voltage comparison circuit are arranged between pulse shaping circuit and data receiving display module,

[0008] The scintillator and SIPM coupling module are used for receiving input radiation energy.

[0009] The pulse shaping circuit is connected with the output signal of the scintillator and SIPM coupling module, and is used for receiving the output signal of the scintillator and SIPM coupling module.

[0010] The signal amplification circuit is connected with the output signal of the pulse shaping circuit, and is used for receiving the output signal of the pulse shaping circuit.

[0011] The voltage comparison circuit is connected with the output signal of the signal amplification circuit, and is used for receiving the output signal of the signal amplification circuit.

[0012] Preferably, the signal amplification circuit comprises an operational amplifier.

[0013] The inverting input terminal of the operational amplifier is connected to the output terminal through a feedback resistor R10; the inverting input terminal of the operational amplifier is provided with an adjusting resistor R9 connected in parallel with the feedback resistor R10; the amplification multiple of the operational amplifier is the ratio of the feedback resistor R10 and the adjusting resistor R9.

[0014] The output terminal of the operational amplifier is connected with the input terminal of the voltage comparison circuit.

[0015] Preferably, the signal amplification circuit further comprises a pole-zero cancellation circuit.

[0016] The pole-zero cancellation circuit comprises a resistor R4 and a capacitor C2 connected in series between the output terminal of the operational amplifier and the input terminal of the voltage comparison circuit, and an adjustable resistor R5 and a resistor R6 connected in parallel with the capacitor C2.

[0017] Preferably, the output end of the pulse shaping circuit is connected to the non-inverting input end of the operational amplifier in the signal amplification circuit through a resistor R1.

[0018] Preferably, the voltage comparison circuit comprises a voltage comparator.

[0019] The output end of the signal amplification circuit is connected to the non-inverting input end of the voltage comparator through a resistor R54.

[0020] The reference voltage is connected to the inverting input end of the voltage comparator through a resistor R56.

[0021] The output end of the voltage comparator is connected to the signal input end of the data receiving and display module through a resistor R55.

[0022] Preferably, the utility model further comprises:

[0023] The power conversion circuit is electrically connected to the power supply end of the scintillator and SIPM coupling module, the pulse shaping circuit, the signal amplification circuit, the voltage comparison circuit and the data receiving and display module.

[0024] Compared with the prior art, the SIPM dose rate probe based on the amplification circuit has the following beneficial effects in the utility model:

[0025] The signal amplification circuit and the voltage comparison circuit are arranged between the pulse shaping circuit and the data receiving and display module, so that the signal amplification circuit can effectively amplify the weak voltage pulse signal output by the pulse shaping circuit, the voltage comparison circuit can eliminate noise of the voltage pulse signal, the amplitude and intensity of the voltage pulse signal can be improved by arranging the positions of the signal amplification circuit and the voltage comparison circuit in the existing SIPM dose rate probe, the problem of distortion or loss of the voltage pulse signal due to attenuation in the transmission process is improved, the probe can detect weaker radiation energy changes, and the sensitivity of the SIPM dose rate probe is improved through the structural design. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to make the purpose, technical scheme and advantages of the utility model more clear, the utility model will be further described in detail below in combination with the drawings, and the drawings are as follows:

[0027] Figure 1 It is a structural schematic view of the SIPM dose rate probe based on the amplification circuit.

[0028] Figure 2 It is a circuit diagram of the pulse shaping circuit.

[0029] Figure 3 It is a circuit diagram of the signal amplification circuit.

[0030] Figure 4 It is a circuit diagram of the voltage comparison circuit.

[0031] Figure 5 This is a circuit diagram of a power conversion circuit. Detailed Implementation

[0032] The following detailed explanation illustrates the specific implementation methods:

[0033] Example:

[0034] This embodiment discloses an SIPM dose rate detector based on an amplifier circuit.

[0035] like Figure 1 As shown, an SIPM dose rate detector based on an amplifier circuit includes a scintillator and SIPM coupling module, a pulse shaping circuit, and a data receiving and display module; a signal amplification circuit and a voltage comparison circuit are arranged between the pulse shaping circuit and the data receiving and display module.

[0036] The scintillator and SIPM coupling module are used to receive the input radiant energy, generate the corresponding optical signal, and then convert the optical signal into an electrical signal.

[0037] In this embodiment, the scintillator (such as CsI(Tl)) and the SIPM coupling module use an existing module, and we have not made any modifications to it. The output of the scintillator is coupled to the input of the SiPM. The scintillator first absorbs radiant energy and then emits an optical signal, which is then converted into an electrical signal by the SIPM. The output of the scintillator is coupled to the input of the SiPM. The radiant energy can be gamma rays or X-rays.

[0038] like Figure 2 As shown, the pulse shaping circuit is connected to the output signal transmission of the scintillator and SIPM coupling module. It is used to receive the electrical signal output by the scintillator and SIPM coupling module and output a voltage pulse signal.

[0039] In this embodiment, the pulse shaping circuit is an existing circuit, and we have not made any modifications to it.

[0040] The signal amplification circuit is connected to the output terminal of the pulse shaping circuit for signal transmission. It is used to receive the voltage pulse signal output by the pulse shaping circuit, amplify the voltage pulse signal, and output the amplified voltage pulse signal.

[0041] The voltage comparator circuit is connected to the output of the signal amplifier circuit for signal transmission. It receives the amplified voltage pulse signal output by the signal amplifier circuit, performs noise cancellation on the amplified voltage pulse signal, and outputs a regular pulse signal. The output of the voltage comparator circuit is also connected to the data receiving and display module for signal transmission.

[0042] Finally, the data receiving and display module receives the voltage pulse signal amplified and compared by the signal amplification circuit and the voltage comparison circuit, and processes the voltage pulse signal through existing means to generate and display and store the radiation dose data, thereby realizing radiation detection.

[0043] In this embodiment, the data receiving and display module is composed of an existing microprocessor, a display and a data storage module, and we do not make any improvement to it, but only change the input into the voltage pulse signal amplified and compared by the signal amplification circuit and the voltage comparison circuit.

[0044] As shown in Figure 3 , the signal amplification circuit comprises an operational amplifier;

[0045] The inverting input end of the operational amplifier is connected to the output end through a feedback resistor R10; the inverting input end of the operational amplifier is provided with an adjusting resistor R9 connected in parallel with the feedback resistor R10; the amplification multiple of the operational amplifier is the ratio of the feedback resistor R10 and the adjusting resistor R9;

[0046] The output end of the operational amplifier is in signal transmission connection with the input end of the voltage comparison circuit.

[0047] The signal amplification circuit further comprises a pole-zero cancellation circuit;

[0048] The pole-zero cancellation circuit comprises a resistor R4 and a capacitor C2 connected in series between the output end of the operational amplifier and the input end of the voltage comparison circuit, and an adjustable resistor R5 and a resistor R6 connected in parallel with the capacitor C2. The effect of improving the resolution can be achieved by adjusting the value of R5.

[0049] The output end of the pulse shaping circuit is connected to the non-inverting input end of the operational amplifier in the signal amplification circuit through a resistor R1.

[0050] As shown in Figure 4 , the voltage comparison circuit comprises a voltage comparator;

[0051] The output end of the signal amplification circuit is connected to the non-inverting input end of the voltage comparator through a resistor R54;

[0052] The reference voltage is connected to the inverting input end of the voltage comparator through a resistor R56;

[0053] The output end of the voltage comparator is connected to the signal input end of the data receiving and display module through a resistor R55.

[0054] The signal amplification circuit and the voltage comparison circuit are arranged between the pulse shaping circuit and the data receiving and display module, so that the signal amplification circuit can effectively amplify the weak voltage pulse signal output by the pulse shaping circuit, the voltage comparison circuit can eliminate noise of the voltage pulse signal, the amplitude and intensity of the voltage pulse signal can be improved by arranging the positions of the signal amplification circuit and the voltage comparison circuit in the existing SIPM dose rate detector, the problem that the voltage pulse signal is distorted or lost due to attenuation in the transmission process is solved, the detector can detect weaker radiation energy changes, and the sensitivity of the SIPM dose rate detector is improved through structural design.

[0055] In the structure of the signal amplification circuit, the inverting input end of the operational amplifier is connected to the output end through a feedback resistor R10, an adjusting resistor R9 is arranged in parallel with the feedback resistor R10 at the inverting input end of the operational amplifier, and the amplification multiple of the operational amplifier is the ratio of the feedback resistor R10 and the adjusting resistor R9. The signal amplification circuit can flexibly adjust the amplification multiple of the operational amplifier by changing the resistance values of the feedback resistor R10 and the adjusting resistor R9, which helps to amplify the voltage pulse signal output by the pulse shaping circuit according to actual needs, that is, the voltage pulse signal can be amplified to different degrees, so that the performance of the SIPM dose rate detector is optimized; meanwhile, the parallel connection of the adjusting resistor R9 can provide a certain stability for the signal amplification circuit, preventing the circuit from entering a nonlinear region due to excessively large or small input signals, so that the normal working state of the signal amplification circuit is maintained; in addition, the design of the extreme zero cancellation circuit can further improve the stability of the signal amplification circuit.

[0056] In the structure of the voltage comparison circuit, noise of the voltage pulse signal can be eliminated, and the problem that the voltage pulse signal is distorted or lost due to attenuation in the transmission process is solved, so that the detector can detect weaker radiation energy changes, and the sensitivity and precision of the SIPM dose rate detector are improved.

[0057] In the specific implementation process, as shown in Figure 5 , the SIPM dose rate detector further includes:

[0058] The power conversion circuit is electrically connected with the power supply end of the scintillator and SIPM coupling module, the preamplifier circuit, the pulse shaping circuit, the signal amplification circuit, the voltage comparison circuit and the data receiving and display module, and is used for providing electric energy for each module and circuit.

[0059] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application but not to limit the technical solutions, and those skilled in the art should understand that those who modify or equivalently replace the technical solutions of the present application without departing from the purpose and scope of the present application should be covered in the scope of the claims of the present application.

Claims

1. An amplification circuit-based SIPM dose rate probe, comprising a scintillator and SIPM coupling module, a pulse shaping circuit and a data receiving and display module; characterized in that: The signal amplification circuit and the voltage comparison circuit are arranged between the pulse shaping circuit and the data receiving and display module. The scintillator and SIPM coupling module is used for receiving input radiation energy. The pulse shaping circuit is connected in signal transmission with the output end of the scintillator and SIPM coupling module, and is used for receiving the signal output by the scintillator and SIPM coupling module. The signal amplification circuit is connected in signal transmission with the output end of the pulse shaping circuit, and is used for receiving the signal output by the pulse shaping circuit. The voltage comparison circuit is connected in signal transmission with the output end of the signal amplification circuit, and is used for receiving the signal output by the signal amplification circuit.

2. The amplifier circuit based SIPM dose rate probe of claim 1, wherein: The output end of the voltage comparison circuit is connected in signal transmission with the data receiving and display module. The signal amplification circuit comprises an operational amplifier. The inverting input end of the operational amplifier is connected to the output end through a feedback resistor R10.

3. The amplifier circuit based SIPM dose rate probe of claim 2, wherein: The inverting input end of the operational amplifier is provided with an adjusting resistor R9 connected in parallel with the feedback resistor R10. The amplification multiple of the operational amplifier is the ratio of the feedback resistor R10 and the adjusting resistor R9.

4. The amplifier circuit based SIPM dose rate probe of claim 2, wherein: The output end of the operational amplifier is connected in signal transmission with the input end of the voltage comparison circuit.

5. The amplifier circuit based SIPM dose rate probe of claim 1, wherein: The signal amplification circuit further comprises a pole-zero cancellation circuit. The pole-zero cancellation circuit comprises a resistor R4 and a capacitor C2 connected in series between the output end of the operational amplifier and the input end of the voltage comparison circuit, and an adjustable resistor R5 and a resistor R6 connected in parallel with the capacitor C2. The output end of the pulse shaping circuit is connected to the non-inverting input end of the operational amplifier in the signal amplification circuit through a resistor R1. The voltage comparison circuit comprises a voltage comparator.

6. The amplifier circuit based SIPM dose rate probe of claim 1, wherein: The output end of the signal amplification circuit is connected to the non-inverting input end of the voltage comparator through a resistor R54. A reference voltage is connected to the inverting input end of the voltage comparator through a resistor R56. The output end of the voltage comparator is connected to the signal input end of the data receiving and display module through a resistor R55. Further comprising: A power conversion circuit is connected in power supply to the scintillator and SIPM coupling module, the pulse shaping circuit, the signal amplification circuit, the voltage comparison circuit and the data receiving and display module.

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