CN116297587A - Multimode Compton imaging detection device and application thereof - Google Patents

Abstract

The present invention provides a multi-mode Compton imaging detection device and its application, including: a casing and a ray source arranged in the casing, a scattering detector, an absorption detector, a visible light imaging unit, a signal processing unit, a central Control board, power supply assembly and display screen; multi-channel scattering detectors are arranged in an array to form two scattering detector arrays; multi-channel absorption detectors are arranged in an array to form two absorption detector arrays; the visible light imaging unit is arranged in the scattering detection One side of the detector; the signal processing unit is connected to the scattering and absorption detectors; the central control board is connected to the signal processing unit and the visible light imaging unit; other components of the power supply component provide power; the display screen is connected to the central control board; and the detection device is applied For the identification and location detection of organic contraband and radioactive nuclides. The detection device in the present invention can realize detection in multiple modes, is convenient to operate, has good portability, has low overall investment cost of the detection device, and saves resources.

Description

A multi-mode Compton imaging detection device and its application

technical field

The invention belongs to the technical field of radiation imaging inspection, and in particular relates to a multi-mode Compton imaging detection device and its application.

Background technique

At present, the detection methods for trace drugs and explosives in the world mainly use ion mobility spectrometry, mass spectrometry and their combined techniques, and the detection of small and large amounts of drugs and explosives mainly relies on radiation imaging technology. Among them, since drugs and explosives are composed of low atomic number elements (C, H, N, O, P, etc.), the material density is low but the electron density is high, the absorption ability to rays is poor but the Compton scattering effect is strong, Organic contraband such as drugs and explosives can be highlighted by using Compton backscatter imaging technology, and the layout of backscatter detectors is flexible. Therefore, backscatter imaging technology is very suitable for interlayer and well-sealed drugs or explosives The imaging detection of prohibited items is widely equipped by customs and border guards.

For the identification and detection of radionuclides or substances, an energy spectrometer is usually used to measure the energy spectrum of the target substance to be measured, and then the obtained characteristic energy spectrum is preprocessed, peak-finding and matched to determine the type of nuclide.

For the positioning of radionuclides, the effective methods mainly include pinhole imaging, coded aperture imaging and Compton scattering imaging. Since the Compton scattering imaging technology does not require a collimator to limit the field of view, it is Portability and imaging viewing angle range are superior to the other two types of technologies. Therefore, imaging radioactive source positioning technology based on Compton forward scattering has also been widely used.

In the prior art, on the one hand, there have been no technical reports on portable detection devices and related devices that simultaneously have organic contraband such as drugs and explosives, and radionuclide identification and positioning. In the prior art, the Compton reverse Scattering imaging realizes the detection of organic substances such as drugs and explosives. The method of using energy spectrometer for radionuclide screening and using Compton forward scattering to realize radionuclide positioning will easily lead to high overall investment costs of detection equipment and waste of resources.

On the other hand, the principle of the mainstream flying spot scanning technology scheme for Compton scattering imaging is to add a rotating disk with slits evenly around the circle at the front of the fan-shaped beam exit of the X-ray machine. The slit intersects with the fan-shaped beam outlet to form a periodic top-to-bottom or left-to-right slit, thereby forming a pencil-shaped or flying-spot-shaped ray beam. Although the scheme is mature, it has the following defects: ①. Most of the X-rays are shielded by the collimator and chopper mechanism during the flying-spot scanning imaging process, the utilization rate of X-rays is extremely low, and the obtained image has a low signal-to-noise ratio and poor resolution. ②, in order to improve the image resolution and signal-to-noise ratio, it is usually necessary to extend the exposure time, but the flying spot scanning speed is limited by the speed of the chopper wheel, which is difficult to meet the needs of high-throughput detection occasions; ③, resulting in flying spot The mechanical mechanism of the point is complex, bulky and heavy, which is not only prone to failure but also not conducive to the miniaturization of the equipment.

Therefore, it is necessary to provide an improved technical solution for the above-mentioned deficiencies in the prior art.

Contents of the invention

In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a multi-mode Compton imaging detection device and its application, which is used to solve the problems in the prior art that can not only detect organic contraband but also detect radiation nuclei. Portable detection equipment for screening and positioning of pixels, and the total investment cost of the detection equipment is high, resulting in waste of resources, and solving the problems of low ray utilization rate, low signal-to-noise ratio of obtained images, and resolution problems in Compton scattering imaging in the prior art. The problem of low efficiency and the mechanical mechanism that produces flying spots is complex, bulky, and poor in portability.

In order to achieve the above purpose and other related purposes, the present invention provides a multi-mode Compton imaging detection device, the detection device includes: a casing and a radiation source arranged in the casing, a scattering detector, an absorption detection Detector, visible light imaging unit, signal processing unit, central control board, power supply components and display screen;

Wherein, the ray source is used to generate a ray beam; the scatter detector is provided with multiple channels, and the scatter detectors of multiple channels are arranged in an array to form two scatter detector arrays; the absorption detector is provided with multiple channels The multi-path absorption detectors are arranged correspondingly to the multi-path scatter detectors, and the multi-path absorption detectors are arranged in an array to form two absorption detector arrays; the visible light imaging unit is arranged on the scatter detector One side of the detector is used to take images of the measured object; the signal processing unit is respectively connected to the scattering detector and the absorption detector to process the received signal; the central control board is connected to the The signal processing unit and the visible light imaging unit are connected to perform data processing and image reconstruction on the received signal; the power supply components are the ray source, the scattering detector, the absorption detector, the visible light imaging The unit, the signal processing unit, the central control board and the display screen provide power; the display screen is connected to the central control board for presenting the image reconstructed by the central control board.

Preferably, the radiation source is a Spindt line array radiation source, and the Spindt line array radiation source is located between the two scattering detector arrays and arranged parallel to the longitudinal direction of the scattering detector arrays.

Preferably, the Spindt line array radiation source includes a substrate and a plurality of electron emitters, a plurality of the electron emitters are arranged in an array on the substrate, and a plurality of the electron emitters and a radiation controller Electrically connected, the ray controller controls the periodic emission and shutdown of the electron emitters, and multiple electron emitters generate flying-spot ray beams in turn, and the flying-spot ray beams interact with the measured object to generate scattered photons.

Preferably, the scattering detector includes a first scintillation crystal, a first light cone and a first photoelectric conversion device sequentially coupled;

The absorption detector includes a second scintillation crystal, a second light cone and a second photoelectric conversion device coupled in sequence.

Preferably, shielding layers and reflective layers are provided around the first scintillation crystal and the second scintillation crystal;

Both the inside of the first light cone and the second light cone are coated with a specular reflection layer, and the specular reflection layer is used for lossless transmission of optical signals;

Both the first photoelectric conversion device and the second photoelectric conversion device are one or a combination of photomultiplier tubes, photodiodes, avalanche photodiodes, and silicon photomultiplier tubes.

Preferably, the signal processing unit includes a signal amplification circuit, an A/D converter, a threshold comparison, a counting circuit and an amplitude analyzer connected in sequence.

Preferably, the power supply assembly includes a power supply battery and a power supply controller, the power supply controller is connected to the power supply battery, and the power supply battery controls the radiation source, scattering detector, absorption The circuits of the detector, visible light imaging unit, signal processing unit, control panel and display screen are on and off.

Preferably, both the scattering detector and the absorption detector are semiconductor detectors.

Preferably, the detection device further includes: a storage unit connected to the central control board for storing the final detection result.

The present invention also provides an application of the above-mentioned multi-mode Compton imaging detection device. The detection device is applied to the imaging detection of organic contraband, as well as the screening and positioning detection of radionuclides.

As mentioned above, the multi-mode Compton imaging detection device and its application of the present invention have the following beneficial effects:

The detection device in the present invention includes a scattering detector and an absorption detector at the same time, and the imaging detection of organic contraband and the screening of radioactive nuclides can be realized by using the scattering detector. For the positioning of nuclides, one detection device can realize multiple modes of detection, which makes the detection equipment easy to operate and has good portability. It is applied to the imaging detection of organic contraband, as well as for the identification and During positioning detection, the overall investment cost of the detection device is low, saving resources.

The detection device in the present invention adopts the Spindt line array ray source to replace the fan beam light source and the flying spot ray generation mechanism of the chopper disc in the prior art, because the scanning control of the Spindt line array ray source is flexible and faster than the mechanical scanning speed , which effectively improves the scattering imaging speed and ray utilization rate, reduces the difficulty of shielding and the accumulated absorbed dose of the operator, and can greatly reduce the complexity of the entire detection device, improve the portability of the device, and obtain a high signal-to-noise ratio and resolution High rate.

Description of drawings

FIG. 1 is a schematic diagram of a partial structure of a multi-mode Compton imaging detection device in a specific embodiment of the present invention.

Fig. 2 is a schematic diagram of the planar structure of a scattering detector in a specific embodiment of the present invention.

Fig. 3 is a schematic diagram of the three-dimensional structure of the absorption detector in a specific embodiment of the present invention.

Fig. 4 is a schematic structural diagram of a Spindt line array radiation source in a specific embodiment of the present invention.

Fig. 5 is a schematic diagram showing the structure of a flying spot ray beam generated by a Spindt line array ray source in a specific embodiment of the present invention.

FIG. 6 is a sectional view along the A-A direction of FIG. 5 .

Fig. 7 is a schematic diagram showing the working principle of the positioning of radionuclides by the multi-mode Compton imaging detection device in a specific embodiment of the present invention.

FIG. 8 is a schematic structural diagram of a multi-mode Compton imaging detection device in a specific embodiment of the present invention.

Component designation description

100 Spindt Line Array Ray Source

101 substrate

102 electron emitter

1021 Flying Spot Ray Beam

200 scatter detectors

201 first scintillation crystal

202 First Cone of Light

203 The first photoelectric conversion device

300 Absorption Detector

301 Second scintillation crystal

302 second light cone

303 Second photoelectric conversion device

400 visible light imaging units

500 signal processing unit

600 central control panel

700 power pack

800 display

900 storage units

Detailed ways

Embodiments of the present invention are described below through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes, and various modifications or changes can be made to the details in this specification based on different viewpoints and applications without departing from the spirit of the present invention.

Please refer to Figures 1 to 8. It should be noted that the diagrams provided in this embodiment are only schematically illustrating the basic idea of the present invention, and only the components related to the present invention are shown in the diagrams rather than the actual ones. The number, shape and size of the components during implementation can be changed at will in the actual implementation of the type, quantity and proportion of each component, and the layout of the components may also be more complex.

The detection device in the present invention includes a scattering detector and an absorption detector at the same time, and the imaging detection of organic contraband and the screening of radioactive nuclides can be realized by using the scattering detector. For the positioning of nuclides, one detection device can realize multiple modes of detection, which makes the detection equipment easy to operate and has good portability. It is applied to the imaging detection of organic contraband, as well as for the identification and During positioning detection, the overall investment cost of the detection device is low, and resources are saved; the detection device in the present invention adopts the Spindt line array ray source to replace the fan beam light source and the flying point ray generation mechanism of the chopper disc in the prior art, due to Spindt The scanning control of the line array radiation source is flexible and faster than mechanical scanning, which effectively improves the scattering imaging speed and radiation utilization, reduces the difficulty of shielding and the cumulative absorbed dose of the operator, and can greatly reduce the complexity of the entire detection device and improve Portability of the device, while obtaining a high signal-to-noise ratio and high resolution graphics.

The present invention provides a multi-mode Compton imaging detection device, which includes: a casing and a radiation source arranged in the casing, a scattering detector 200, an absorption detector 300, a visible light imaging unit 400, and a signal processing unit 500, central control board 600, power supply assembly 700 and display screen;

Wherein, the ray source is used to generate the ray beam; the scattering detector 200 is provided with multiple channels, and the multi-channel scattering detectors 200 are arranged in an array to form two arrays of the scattering detectors 200; the absorption detector 300 is provided with multiple channels, and the multi-channel absorbing The detectors 300 are respectively arranged corresponding to the multi-channel scattering detectors 200, and the multi-channel absorption detectors 300 are arranged in an array to form two arrays of absorption detectors 300; the visible light imaging unit 400 is arranged on one side of the scattering detector 200 for photographing The image of the measured object; the signal processing unit 500 is respectively connected to the scattering detector 200 and the absorption detector 300 for processing the received signal; the central control board 600 is connected to the signal processing unit 500 and the visible light imaging unit 400, Used for data processing and image reconstruction of the received signals; the power supply assembly 700 provides power for the radiation source, the scattering detector 200, the absorption detector 300, the visible light imaging unit 400, the signal processing unit 500, the central control board 600 and the display screen The display screen is connected with the central control board 600 for presenting the image reconstructed by the central control board 600 .

Specifically, the signal processed by the signal processing unit 500 is transmitted to the central controller, and the central controller performs data processing and image reconstruction on the received signal, while the visible light imaging unit 400 is mainly used to photograph the measured object, and the photographed The image information of the image is transmitted to the central controller, which can play an auxiliary role in the data processing and image reconstruction of the object under test; 400 may also include other elements, which are not overly limited here.

Specifically, the scattering detector 200 is used to realize energy spectrum detection, dose rate detection, and backscatter imaging; the absorption detector 300 is arranged behind the scattering detector 200, and is used to absorb the gamma photon energy scattered by the scattering detector 200 and detect The position of the scattered γ photon is combined with the orientation of the γ photon received by the scattering detector 200 and the direction of the γ photon received by the absorption detector 300 to reconstruct and determine the position of the ray source.

As an example, the radiation source is a Spindt line array radiation source 100, and the Spindt line array radiation source 100 is located between two scatter detector arrays 200 and arranged parallel to the longitudinal direction of the scatter detector arrays 200.

As an example, the Spindt line array radiation source 100 includes a substrate 101 and a plurality of electron emitters 102, and the plurality of electron emitters 102 are arranged in an array on the substrate 101, and the plurality of electron emitters 102 are electrically connected to the radiation controller. connection, the radiation controller controls the periodic emission and shutdown of the electron emitters 102, multiple electron emitters 102 generate flying-spot beams 1021 in turn, and the flying-spot beams 1021 interact with the measured object to produce scattered photons.

Specifically, the electron emitter 102 uses photoelectric emission, field emission or secondary emission to supply electrons, the power of the Spindt line array radiation source 100 is turned on, and the electron emitter 102 is controlled from top to bottom or from left to right by the radiation controller. The right is periodically turned on and off one by one, and the electron emitter 102 generates a conical flying-spot ray beam 1021 in turn. When the conical flying-spot ray beam 1021 is transmitted to the surface of the measured object, it will generate Compton backscattering with the electrons in the measured object. Scattered photons are received by the backscatter detectors 200 arranged on both sides of the Spindt line array ray source 100, and a voltage signal is generated through photoelectric conversion; Compared with the mainstream flying-spot scanning technology of Compton scattering imaging in the prior art, the scanning speed in this embodiment is faster, which can effectively improve the backscatter imaging speed, reduce the difficulty of shielding and the accumulated absorbed dose of the operator.

As an example, the scattering detector 200 includes a first scintillation crystal 201, a first light cone 202, and a first photoelectric conversion device 203 coupled in sequence; the absorption detector 300 includes a second scintillation crystal 301, a second light cone coupled in sequence 302 and the second photoelectric conversion device 303.

Specifically, a scintillator is a kind of material that can emit light after absorbing high-energy particles or rays, and is usually processed into scintillation crystals in applications; the first scintillation crystal 201 in the scattering detector 200 receives scattered photons and converts them into visible light , the visible light is transmitted to the first photoelectric conversion device 203 after multiple reflections by the first light cone 202, and the first photoelectric conversion device 203 converts the light signal into a voltage signal. Referring to FIG. 5, the first scintillation crystal 201 is located at the front end , the first light cone 202 is coupled between the first scintillation crystal 201 and the first photoelectric conversion device 203; referring to FIG. 6 , the second light cone 302 in the absorption detector 300 is coupled between the second scintillation crystal 301 and the second Between the light cones 302; the first scintillation crystal 201 in this embodiment is relatively small in density and thickness, such as 2-5 mm thick GOS (gadolinium oxysulfide) film, CsI (cesium iodide) crystal, CZT (cadmium zinc telluride) crystals, etc.; the second scintillation crystal 301 is relatively large in density and thickness, such as 1-2 cm thick CsI (cesium iodide), GOS (gadolinium oxysulfide), GAGG (gadolinium aluminum gallium garnet) , CZT (cadmium zinc telluride) and other crystals.

When using the detection device in the present invention to locate the radionuclide, the gamma rays that release energy from the decay of the _radionuclide first enter the scatter detector 200, and produce Compton scattering in the scatter detector 200, resulting in The energy is deposited E ₁ , the scattered photons are emitted through the scattering detector 200 , and a photoelectric effect is generated in the absorption detector 300 , and the photon energy is completely absorbed by the detector.

As an example, shielding layers and reflective layers are provided around the first scintillation crystal 201 and the second scintillation crystal 301; the insides of the first light cone 202 and the second light cone 302 are all coated with a specular reflection layer, and the specular reflection Layers are used for lossless transmission of optical signals; the first photoelectric conversion device 203 and the second photoelectric conversion device 303 are either one or a combination of photomultiplier tubes, photodiodes, avalanche photodiodes, and silicon photomultiplier tubes.

Specifically, the shielding layer is used to shield visible light and rays. On the one hand, it improves the utilization rate of rays, and on the other hand, it reduces the harm of operators from rays. The reflective layer reflects the rays that may leak back to the reaction area, improving the utilization of rays. However, in this embodiment, there is no excessive limitation on the materials selected for the shielding layer and the reflective layer.

As an example, the signal processing unit 500 includes a signal amplification circuit, an A/D converter, a threshold comparison, a counting circuit, and an amplitude analyzer arranged in sequence.

Specifically, the signal amplifying circuit is a circuit that amplifies weak signals. In this embodiment, the signal amplifying circuit further amplifies the voltage signal; the A/D converter is an electronic component that converts an analog signal into a digital signal. In this embodiment In the embodiment, the amplified voltage signal is converted into a digital signal; the threshold comparison includes an adaptive Steind unbiased risk estimation threshold, an average threshold method or a maximum and minimum threshold method; the counting circuit is composed of a basic counting unit and some control The gate composition; the amplitude analyzer is an instrument for measuring the amplitude distribution of the electric pulse signal. It classifies the pulse signal according to the amplitude and records the number of each type of signal. It is often used to analyze the output signal of the ray detector and measure the energy spectrum of the ray; Specifically, regarding the specific structure of each element in the signal processing unit 500, there is no excessive limitation here, as long as it can meet actual needs.

As an example, the power supply assembly 700 includes a power supply battery and a power supply controller, the power supply controller is connected to the power supply battery, and the power supply battery controls the ray source, the scattering detector 200, the absorption detector 300, the visible light imaging unit 400, the signal processing The circuits of the unit 500, the control board and the display screen are switched on and off.

Specifically, the circuit on-off of different components is controlled by the power controller. When performing radionuclide screening, energy spectrum detection or radioactive dose detection, only one or more of the scattering detectors 200 and the signal processing unit 500 , the control panel and the display screen are energized; when radionuclide positioning is performed, all circuits other than the radiation source and visible light imaging unit 400 need to be connected; when organic contraband detection is performed, the circuits related to the absorption detector 300 Disconnect and connect other circuits.

As an example, both the scatter detector 200 and the absorption detector 300 are semiconductor detectors.

Specifically, semiconductor detectors are radiation detectors that use semiconductor materials as the detection medium. The most common semiconductor materials are germanium and silicon. The basic principle is that charged particles generate electron-hole pairs in the sensitive volume of the semiconductor detector. - The hole pairs drift under the action of an external electric field to output a signal. The semiconductor detector in this embodiment is a CZT (cadmium zinc telluride) or GAGG (gadolinium aluminum gallium garnet) semiconductor detector.

As an example, the detection device further includes: a storage unit 900 connected to the central control board 600 for storing the final detection result.

In order to better understand the multi-mode Compton imaging detection device in the present invention, the present invention also provides an application of a multi-mode Compton imaging detection device, which is used for imaging detection of organic contraband, and The detection device is used for the screening and location detection of radionuclides, and the specific application is as in the following examples.

Example 1

This embodiment provides a multi-mode Compton imaging detection device applied to the screening of radionuclides and radiation dose detection. The specific detection method includes the following steps:

a1. The power controller controls the power supply assembly 700 to turn on one or more circuits of the scatter detector 200, the signal processing unit 500, the control panel and the display screen;

a2. After the first scintillation crystal 201 on the scattering detector 200 is excited and de-excited by the characteristic gamma rays released by the decay of the radionuclide, it generates fluorescence or phosphorescence, and the fluorescence or phosphorescence passes through the first light cone 202 multiple times reflection, transmitted to the first photoelectric conversion device 203 to convert the optical signal into a voltage signal;

a3. The voltage signal is transmitted to the signal processing unit 500, and the spectrogram is formed through further signal amplification, A/D conversion, threshold comparison, counting circuit counting and amplitude analyzer analysis;

a4. The formed spectrogram is transmitted to the central control panel 600, and the spectral peaks in the spectrogram are matched and compared with those of nuclides in the database by a peak matching algorithm, and then a graph is reconstructed and the measured radiation nuclei are displayed on the display screen. The characteristic energy spectrum of the nuclide, the matching result of the nuclide and the dose information.

Example 2

This embodiment also provides a multi-mode Compton imaging detection device applied to the positioning detection of radionuclides. The specific detection method includes the following steps:

b1. The power controller controls the power supply assembly 700 to turn on the circuits of the scattering detector 200 and the absorption detector 300, and turn on the circuits of the visible light imaging unit 400, the signal processing unit 500, the control board and the display screen;

b2. Aim the probe of the visible light imaging unit 400 and the scattering detector 200 at the suspicious azimuth and viewing angle direction of the radionuclide to be measured, and the visible light imaging unit 400 takes pictures of the azimuth of the radionuclide to be measured, and the energy released by the decay of the radionuclide is E ₀ The gamma-rays from scatter first enter the scattering detector 200, and generate Compton scattering in the scattering detector 200, wherein, the photons that generate Compton scattering generate energy deposition E ₁ on the scattering detector 200, and the scattering position is (x ₁ , y ₁ , z ₁ ), the first scintillation crystal 201 generates fluorescence or phosphorescence after being excited and de-excited, and the fluorescence is converted into a first electrical signal by the first light cone 202 and the first photoelectric conversion device 203, and the first electrical signal processed by the signal processing unit 500, and record the range information of the ray incident position;

b3. After the Compton-scattered photon is emitted by the scattering detector 200, a photoelectric effect is generated in the absorption detector 300, and the photon energy is completely absorbed by the absorption detector 300. During the absorption process, the electrons outside the nucleus of the second scintillation crystal 301 are excited, and the electrons Fluorescence is generated after de-excitation, and the fluorescence is converted into a second electrical signal by the second light cone 302 and the second photoelectric conversion device 303, and the second electrical signal is processed by the signal processing unit 500, and records the range information of the ray incident position; wherein, the gamma ray The deposition energy in the absorption detector 300 is E ₀ −E ₁ , and the absorption position is (x ₂ , y ₂ , z ₂ ).

式中m_ec²为电子的静止质量。According to the Compton imaging principle, the emission position of gamma rays can be determined at a certain point on the surface of the cone, the apex of the cone is on the scattering detector 200, the coordinates are (x ₁ , y ₁ , z ₁ ), and the axis of the cone is the scattering Point (x ₁ , y ₁ , z ₁ ) and absorption point (x ₂ , y ₂ , z ₂ ) are on a straight line, where:

Where m _e c ² is the rest mass of the electron.

This embodiment can determine the location range of the radionuclide. Through multiple detections and statistical calculations of the intersection points of multiple cones, combined with the graphics captured by the visible light imaging unit 400, the specific position of the radioactive source can be determined, and the radionuclide can be realized. location detection.

Example 3

This embodiment also provides a multi-mode Compton imaging detection device applied to the detection of organic contraband. The specific detection method includes the following steps:

c1, the power supply controller controls the power supply assembly 700 to turn on the Spindt line array ray source 100, the circuits of the two scattering detectors 200 arrays, the circuits of the signal processing unit 500, the control panel and the display screen, and close the circuit of the absorption detector 300;

c2. Align the scatter detector 200 array with the object to be measured, and the radiation controller controls the electron emitters 102 to be turned on and off periodically one by one from top to bottom or from left to right, and multiple electron emitters 102 take turns to generate conical flying bursts The line beam 1021 and the conical flying spot ray beam 1021 interact with the object to be measured, and the rays that produce Compton backscattering effects are received by the arrays of backscatter detectors 200 located on both sides of the Spindt line array ray source 100 to form voltage signals;

c3. After the voltage signal is transmitted to the signal processing unit 500 for processing, the electron density distribution image of the measured point can be obtained, and then transmitted to the central control board 600;

c4. Move the detection device left and right or up and down at a constant speed to obtain electron density images of multiple measured points. The central control board 600 reconstructs and stitches the multi-point electron density images to obtain the electron density image of the entire measured object.

In summary, the detection device in the present invention includes a scattering detector and an absorption detector at the same time, and the imaging detection of organic contraband and the screening of radionuclides can be realized by using the scattering detector, and the scattering detector and the absorption detector can also be used simultaneously. The detector realizes the positioning of radionuclides, and the use of one detection device can realize the detection of multiple modes, which makes the detection equipment easy to operate and has good portability. It is applied to the imaging detection of organic contraband and used for radiation During the screening and positioning detection of nuclides, the overall investment cost of the detection device is low, and resources are saved; the detection device in the present invention adopts the Spindt line array ray source to replace the fan beam light source and the flying spot ray of the chopper disc in the prior art Generating mechanism, because the scanning control of the Spindt line array radiation source is flexible and faster than mechanical scanning, it effectively improves the scattering imaging speed and radiation utilization, reduces the difficulty of shielding and the cumulative absorbed dose of the operator, and can greatly reduce the entire detection device. The complexity of the device improves the portability of the device, and at the same time the obtained graphics have a high signal-to-noise ratio and high resolution. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial application value.

The above-mentioned embodiments only illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical ideas disclosed in the present invention should still be covered by the claims of the present invention.

Claims (10)

1. A multimode compton imaging detection apparatus, said detection apparatus comprising: the device comprises a shell, a radiation source, a scattering detector, an absorption detector, a visible light imaging unit, a signal processing unit, a central control board, a power supply assembly and a display screen, wherein the radiation source, the scattering detector, the absorption detector, the visible light imaging unit, the signal processing unit, the central control board, the power supply assembly and the display screen are arranged in the shell;

wherein the radiation source is used for generating a radiation beam; the scattering detector is provided with a plurality of paths, and the plurality of paths of scattering detector arrays are arranged to form two scattering detector arrays; the absorption detectors are provided with a plurality of paths, the plurality of paths of absorption detectors are respectively and correspondingly arranged with the plurality of paths of scattering detectors, and the plurality of paths of absorption detector arrays are arranged to form two absorption detector arrays; the visible light imaging unit is arranged on one side of the scattering detector and is used for shooting an image of the measured object; the signal processing unit is respectively connected with the scattering detector and the absorption detector and is used for processing the received signals; the central control board is connected with the signal processing unit and the visible light imaging unit and is used for carrying out data processing and image reconstruction on the received signals; the power supply component provides power for the ray source, the scattering detector, the absorption detector, the visible light imaging unit, the signal processing unit, the central control panel and the display screen; the display screen is connected with the central control panel and used for presenting images reconstructed by the central control panel.

2. The multimode compton imaging detection apparatus of claim 1 wherein: the radiation source is a Spindt line array radiation source, and the Spindt line array radiation source is positioned between the two scattering detector arrays and is arranged in parallel with the longitudinal direction of the scattering detector arrays.

3. The multimode compton imaging detection apparatus of claim 2 wherein: the Spindt line array ray source comprises a substrate and a plurality of electron emitters, the electron emitters are arranged on the substrate in an array mode, the electron emitters are electrically connected with a ray controller, the ray controller controls the electron emitters to periodically emit and close, the electron emitters alternately generate flying spot ray beams, and the flying spot ray beams act with an object to be measured to generate scattered photons.

4. The multimode compton imaging detection apparatus of claim 1 wherein: the scattering detector comprises a first scintillation crystal, a first light cone and a first photoelectric conversion device which are sequentially coupled and connected;

the absorption detector comprises a second scintillation crystal, a second light cone and a second photoelectric conversion device which are sequentially coupled and connected.

5. The multimode compton imaging detection apparatus of claim 4 wherein: the periphery of the first scintillation crystal and the periphery of the second scintillation crystal are respectively provided with a shielding layer and a reflecting layer;

the inside of the first light cone and the inside of the second light cone are respectively coated with a specular reflection layer, and the specular reflection layers are used for lossless transmission of optical signals;

the first photoelectric conversion device and the second photoelectric conversion device are one or a combination of a photomultiplier tube, a photodiode, an avalanche photodiode and a silicon photomultiplier tube.

6. The multimode compton imaging detection apparatus of claim 1 wherein: the signal processing unit comprises a signal amplifying circuit, an A/D converter, a threshold comparison circuit, a counting circuit and an amplitude analyzer which are sequentially connected.

7. The multimode compton imaging detection apparatus of claim 1 wherein: the power supply assembly comprises a power supply battery and a power supply controller, the power supply controller is connected with the power supply battery, and the power supply battery controls the on-off of circuits of the ray source, the scattering detector, the absorption detector, the visible light imaging unit, the signal processing unit, the control panel and the display screen through the power supply controller.

8. The multimode compton imaging detection apparatus of claim 1 wherein: the scatter detector and the absorption detector are both semiconductor detectors.

9. The multimode compton imaging detection apparatus of claim 1 wherein: the detection device further includes: and the storage unit is connected with the central control board and used for storing the final detection result.

10. Use of a multimode compton imaging detection device according to any one of claims 1 to 9, characterized in that: the detection device is applied to imaging detection of organic contraband and screening and positioning detection of radioactive nuclides.

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