A device and method for gamma ray spectrum counting measurement

Abstract

The present invention discloses a device and method for gamma-ray energy spectrum counting measurement, belonging to the technical field of gamma-ray energy spectrum measurement. The device of the present invention comprises: an amplifier circuit, the amplifier circuit receives a gamma-ray energy signal and converts the gamma-ray energy signal into an analog signal; a plurality of measurement branches, the measurement branch receives the analog signal, sends a conversion start signal to the logic control circuit, finds the peak of the analog signal and maintains the level of the peak, converts the level into a digital signal and outputs it; a logic control circuit, the logic control circuit receives the conversion start signal, sends a conversion start signal delay for a preset time, closes the measurement branch, and opens the next measurement branch; a storage circuit receives a digital signal, and determines the count value of the gamma-ray energy spectrum according to the digital signals output by the received plurality of measurement branches. The present invention greatly improves the gamma-ray energy spectrum counting rate, and the counting rate is mainly restricted by the scintillator decay time.

Description

Technical Field

[0001] The present invention relates to the technical field of gamma-ray energy spectrum measurement, and more particularly to a device and method for gamma-ray energy spectrum counting measurement. Background Art

[0002] Cerium-doped lanthanum bromide (LaBr3:Ce) scintillation crystal is the hottest new inorganic scintillation crystal material in international research and application. It has excellent characteristics such as high light output (greater than 60000Ph / MeV), short decay time (less than 30ns), high energy resolution (less than 4%), etc. The ideal maximum counting rate is close to 3X107cps;

[0003] Generally, a lanthanum bromide X-ray diffraction spectrometer is composed of an amplifier circuit 1, a linear gate 2, a discriminator 3, a logic control circuit 4, a peak holding circuit 5, an analog-to-digital conversion circuit 6, and a storage circuit 7.

[0004] The conversion time (Tt) of the above spectrometer is composed of the lanthanum bromide rise time (t1), the sampling and holding time (t2), the analog-to-digital conversion circuit conversion time (t3), and the storage circuit storage time (t4). The total conversion time is also called the dead time.

[0005] Tt=t1+t2+t3+t4

[0006] To improve high count rate performance, the prior art uses the following methods:

[0007] 1. Choose a high-performance ADC to reduce t3 and thus Tt. Disadvantages: Limited improvement.

[0008] 2. Use pure digital circuits to make continuous ADC with high sampling rate. Disadvantages: reduced energy resolution and high power consumption

[0009] 3. The digital circuit starting from AD conversion adopts pipeline method. Disadvantages: high cost Summary of the invention

[0010] In view of the above problems, the present invention proposes a device for measuring gamma-ray energy spectrum counting, comprising:

[0011] an amplifier circuit, the amplifier circuit receiving the gamma-ray energy signal and converting the gamma-ray energy signal into an analog signal;

[0012] Multiple measuring branches, the measuring branches receive analog signals, send conversion start signals to the logic control circuit, find the peak of the analog signal and maintain the level of the peak, convert the level into digital signals and output;

[0013] A logic control circuit, wherein the logic control circuit receives a conversion start signal, sends a conversion start signal for a preset delay time, closes a measurement branch, and opens a next measurement branch;

[0014] The storage circuit receives the digital signal and determines the count value of the gamma-ray energy spectrum according to the received digital signals output by the multiple measurement branches.

[0015] Optional, measurement branch, including:

[0016] A linear gate and discriminator, wherein the linear gate and discriminator receive an analog signal;

[0017] A peak holding circuit, wherein the peak holding circuit finds the peak of the analog signal and holds the level of the peak;

[0018] The analog-to-digital conversion circuit converts the level into a digital signal.

[0019] Optionally, the logic control circuit is activated when the rising edge of the analog signal received by the discriminator exceeds a threshold.

[0020] Optionally, the preset time is the sum of the rise time and the decay time of the amplifier circuit.

[0021] Optionally, after the measurement of multiple measurement branches is completed, the logic circuit opens the first measurement branch that receives the analog signal and continues to receive the analog signal until the analog signal is sent.

[0022] Optionally, the count value is the sum of digital signals output by multiple measurement branches.

[0023] The present invention also proposes a method for measuring the gamma-ray energy spectrum counting, comprising:

[0024] Controlling the amplifying circuit to receive the gamma-ray energy signal and converting the gamma-ray energy signal into an analog signal;

[0025] The control and measurement branch receives the analog signal, sends a conversion start signal to the logic control circuit, finds the peak of the analog signal and maintains the level of the peak, converts the level into a digital signal and outputs it;

[0026] The control logic control circuit receives the conversion start signal, sends the conversion start signal for a preset delay time, closes the measurement branch, and opens the next measurement branch;

[0027] The storage circuit is controlled to receive the digital signal and determine the count value of the gamma-ray energy spectrum according to the received digital signals output by the multiple measurement branches.

[0028] Optionally, the measuring branch includes multiple measuring branches, and the measuring branch includes:

[0029] A linear gate and discriminator, wherein the linear gate and discriminator receive an analog signal;

[0030] A peak holding circuit, wherein the peak holding circuit finds the peak of the analog signal and holds the level of the peak;

[0031] The analog-to-digital conversion circuit converts the level into a digital signal.

[0032] Optionally, the logic control circuit is activated when the rising edge of the analog signal received by the discriminator exceeds a threshold.

[0033] Optionally, the preset time is the sum of the rise time and the decay time of the amplifier circuit.

[0034] Optionally, after the measurement of multiple measurement branches is completed, the logic circuit opens the first measurement branch that receives the analog signal and continues to receive the analog signal until the analog signal is sent.

[0035] Optionally, the count value is the sum of digital signals output by multiple measurement branches.

[0036] The present invention greatly improves the gamma-ray energy spectrum counting rate. The counting rate is mainly restricted by the scintillator decay time. When the counting rate is improved, the resolution is not affected. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a structural diagram of the device of the present invention;

[0038] Figure 2 is a flow chart of the method of the present invention;

[0039] 1: amplifier circuit, 2: linear gate (including: 2-1, 2-2, ... 2-n), 3: discriminator (including: 3-1, 3-2, ... 3-n), 4: logic control circuit, 5: peak holding circuit (including: 5-1, 5-2, ... 5-n), 6: analog-to-digital conversion circuit (including: 6-1, 6-2, ... 6-n), 7: storage circuit. DETAILED DESCRIPTION

[0040] Now, exemplary embodiments of the present invention are described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0041] Unless otherwise specified, the terms (including technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0042] The present invention proposes a device for measuring gamma-ray energy spectrum counting, such as Figure 1 As shown, including:

[0043] an amplifier circuit, the amplifier circuit receiving the gamma-ray energy signal and converting the gamma-ray energy signal into an analog signal;

[0044] Multiple measuring branches, the measuring branches receive analog signals, send conversion start signals to the logic control circuit, find the peak of the analog signal and maintain the level of the peak, convert the level into digital signals and output;

[0045] A logic control circuit, wherein the logic control circuit receives a conversion start signal, sends a conversion start signal for a preset delay time, closes a measurement branch, and opens a next measurement branch;

[0046] The storage circuit receives the digital signal and determines the count value of the gamma-ray energy spectrum according to the received digital signals output by the multiple measurement branches.

[0047] Measurement branches, including:

[0048] A linear gate and discriminator, wherein the linear gate and discriminator receive an analog signal;

[0049] A peak holding circuit, wherein the peak holding circuit finds the peak of the analog signal and holds the level of the peak;

[0050] The analog-to-digital conversion circuit converts the level into a digital signal.

[0051] When the rising edge of the analog signal received by the discriminator exceeds the threshold, the logic control circuit is activated.

[0052] The preset time is the sum of the rise time and the decay time of the amplifier circuit.

[0053] After the measurement of multiple measurement branches is completed, the logic circuit opens the first measurement branch that receives the analog signal and continues to receive the analog signal until the analog signal is sent.

[0054] The count value is the sum of the digital signals output by multiple measurement branches.

[0055] The present invention will be further described below in conjunction with embodiments:

[0056] like Figure 1As shown, linear gates (including: 2-1, 2-2, ... 2-n), discriminators (including: 3-1, 3-2, ... 3-n), peak holding circuits (including: 5-1, 5-2, ... 5-n), analog-to-digital conversion circuits (including: 6-1, 6-2, ... 6-n); the number n of required branch circuits is determined according to the sum of the rise time and decay time (tp) of the amplifier circuit, and the total conversion time (Tt), where n is an integer and n is greater than Tt / tp.

[0057] In the initial state, except for the linear gate 2-1, all other linear gates are closed. The logic control circuit 4 ensures that only one linear gate is open at any time.

[0058] The analog signal output by the amplifier circuit 1 passes through the linear gate 2-1 and enters the discriminator 3-1. When the rising edge of the signal exceeds the threshold, the discriminator 3-1 sends a conversion start signal to the logic control circuit 4, telling the control circuit to start the subsequent work of this branch (the peak holding circuit 5-1 finds the peak and holds the level, the analog-to-digital conversion circuit 6-1 converts the level into digital, and the storage circuit 7 receives the conversion result from the analog-to-digital conversion circuit 6-1). After receiving the conversion start signal, the control circuit delays for a time Tp (the sum of the rise time and the decay time of the amplifier circuit), closes the linear gate 2-1, and then immediately opens the linear gate 2-2 of the next branch.

[0059] After the linear gate 2-2 of the branch is opened, branch 2 starts to work.

[0060] The logic control circuit 4 makes each branch work in sequence according to the above logic; after the branch n finishes working, the branch 1 starts working again.

[0061] The present invention also proposes a method for measuring the gamma-ray energy spectrum counting, such as Figure 2 As shown, including:

[0062] Controlling the amplifying circuit to receive the gamma-ray energy signal and converting the gamma-ray energy signal into an analog signal;

[0063] The control and measurement branch receives the analog signal, sends a conversion start signal to the logic control circuit, finds the peak of the analog signal and maintains the level of the peak, converts the level into a digital signal and outputs it;

[0064] The control logic control circuit receives the conversion start signal, sends the conversion start signal for a preset delay time, closes the measurement branch, and opens the next measurement branch;

[0065] The storage circuit is controlled to receive the digital signal and determine the count value of the gamma-ray energy spectrum according to the received digital signals output by the multiple measurement branches.

[0066] The measuring branch includes a plurality of measuring branches, and the measuring branch includes:

[0067] A linear gate and discriminator, wherein the linear gate and discriminator receive an analog signal;

[0068] A peak holding circuit, wherein the peak holding circuit finds the peak of the analog signal and holds the level of the peak;

[0069] The analog-to-digital conversion circuit converts the level into a digital signal.

[0070] When the rising edge of the analog signal received by the discriminator exceeds the threshold, the logic control circuit is activated.

[0071] The preset time is the sum of the rise time and the decay time of the amplifier circuit.

[0072] After the measurement of multiple measurement branches is completed, the logic circuit opens the first measurement branch that receives the analog signal and continues to receive the analog signal until the analog signal is sent.

[0073] The count value is the sum of digital signals output by multiple measurement branches.

[0074] The present invention greatly improves the gamma-ray energy spectrum counting rate. The counting rate is mainly restricted by the scintillator decay time. When the counting rate is improved, the resolution is not affected.

[0075] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0076] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1A device that provides the functions specified in a block or multiple blocks.

[0077] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0078] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0079] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0080] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A device for measuring gamma-ray energy spectrum counting, the device comprising: an amplifier circuit, the amplifier circuit receiving the gamma-ray energy signal and converting the gamma-ray energy signal into an analog signal; Multiple measuring branches, the measuring branches receive analog signals, send conversion start signals to the logic control circuit, find the peak of the analog signal and maintain the level of the peak, convert the level into digital signals and output them; A logic control circuit, wherein the logic control circuit receives a conversion start signal, sends a conversion start signal for a preset delay time, closes a measurement branch, and opens a next measurement branch; A storage circuit receives the digital signal and determines the count value of the gamma-ray energy spectrum according to the received digital signals output by the multiple measurement branches; The measuring branch comprises: A linear gate and discriminator, wherein the linear gate and discriminator receive an analog signal; A peak holding circuit, wherein the peak holding circuit finds the peak of the analog signal and holds the level of the peak; Analog-to-digital conversion circuit, converting the level into digital signal; After the measurement of the multiple measurement branches is completed, the logic control circuit opens the first measurement branch that receives the analog signal and continues to receive the analog signal until the analog signal is sent.

2. The device according to claim 1, wherein the logic control circuit is activated when the rising edge of the analog signal received by the discriminator exceeds a threshold. 3 . The device according to claim 1 , wherein the preset time is the sum of a rise time and a decay time of the amplifier circuit. The device according to claim 1 , wherein the count value is the sum of digital signals output by a plurality of measurement branches.

5. A method for measuring gamma-ray energy spectrum counting using the device according to any one of claims 1 to 4, the method comprising: Controlling the amplifying circuit to receive the gamma-ray energy signal and converting the gamma-ray energy signal into an analog signal; The control measurement branch receives the analog signal, sends a conversion start signal to the logic control circuit, finds the peak of the analog signal and maintains the level of the peak, converts the level into a digital signal and outputs it; The control logic control circuit receives the conversion start signal, sends the conversion start signal for a preset delay time, closes the measurement branch, and opens the next measurement branch; Controlling the storage circuit, receiving the digital signal, and determining the count value of the gamma-ray energy spectrum according to the received digital signals output by the multiple measurement branches; The measuring branch includes a plurality of measuring branches, and the measuring branch includes: A linear gate and discriminator, wherein the linear gate and discriminator receive an analog signal; A peak holding circuit, wherein the peak holding circuit finds the peak of the analog signal and holds the level of the peak; Analog-to-digital conversion circuit, converting the level into digital signal; After the measurement of the multiple measurement branches is completed, the logic control circuit opens the first measurement branch that receives the analog signal and continues to receive the analog signal until the analog signal is sent.

6. The method according to claim 5, wherein the logic control circuit is activated when the rising edge of the analog signal received by the discriminator exceeds a threshold. 7 . The method according to claim 5 , wherein the preset time is the sum of a rise time and a decay time of the amplifier circuit.

8. The device according to claim 5, wherein the count value is the sum of digital signals output by a plurality of measurement branches.

Images