Backscatter imaging device

Abstract

The invention provides back scattering imaging equipment, which has a first inspection state and a second inspection state, and comprises a main cabin body configured to be provided with a radiation source and a main back scattering detector; n auxiliary cabins, wherein each auxiliary cabin is configured to install an auxiliary back scattering detector; wherein in the first inspection state, the main cabin body is arranged at a first target position, the radiation source is configured to perform radiation scanning on a first type of target objects, and the main back scattering detector is configured to receive main back scattering signals of the first type of target objects so as to obtain a first radiation image; in a second inspection state, the main cabin body is switched from the first target position to a second target position, the at least one auxiliary cabin body is arranged at the first target position, the radiation source is configured to perform radiation scanning on a second type of target objects, and the main back scattering detector is configured to receive main back scattering signals of the second type of target objects; the at least one auxiliary back scattering detector is configured to receive at least one auxiliary back scattering signal of the second type of target object.

Description

Technical Field

[0001] This application relates to the field of radiation imaging, and more specifically to a backscatter imaging device. Background Technology

[0002] Backscatter imaging equipment utilizes the Compton scattering effect to efficiently detect contraband with low atomic numbers. It uses an X-ray source and a modulation device (such as a flywheel) to form a pen-beam scanning object. The signal is collected and processed by a backscatter detector to create an image. The core components include the X-ray source, modulation device, detector, controller, and auxiliary equipment such as heat dissipation and cooling. Typically, all components of a backscatter imaging device need to be centrally installed, resulting in an excessively large device size, increasing the difficulty of transportation and installation, and affecting insulation or cooling efficiency. Furthermore, backscatter imaging equipment is usually fixed in location and only suitable for objects of a fixed size; for larger (e.g., taller) objects, the radiation imaging effect is poor. Summary of the Invention

[0003] In view of the above problems, this application provides a backscatter imaging device capable of detecting objects of different sizes.

[0004] According to a first aspect of this application, a backscatter imaging device is provided, having a first inspection state and a second inspection state. The backscatter imaging device includes: a main chamber configured to install a radiation source and a main backscatter detector; and N auxiliary chambers, each configured to install an auxiliary backscatter detector, where N is an integer greater than or equal to 1. In the first inspection state, the main chamber is placed at a first target position, the radiation source is configured to perform a radiation scan on a first type of target object, and the main backscatter detector is configured to receive the main backscatter signal of the first type of target object to obtain a first radiation image. In the second inspection state, the main chamber switches from the first target position to a second target position, at least one auxiliary chamber is placed at the first target position, the radiation source is configured to perform a radiation scan on a second type of target object, the main backscatter detector is configured to receive the main backscatter signal of the second type of target object, and at least one auxiliary backscatter detector in the at least one auxiliary chamber is configured to receive at least one auxiliary backscatter signal of the second type of target object. The main backscatter signal of the second type of target object and at least one auxiliary backscatter signal are used to fuse to obtain a second radiation image. The size of the second type of target object is larger than the size of the first type of target object, and the second target position is higher than the first target position above the ground.

[0005] According to an embodiment of this application, the N auxiliary compartments include a first auxiliary compartment and a second auxiliary compartment. In the second inspection state, the first auxiliary compartment is located above the main compartment, and the second auxiliary compartment is placed at the first target position, located below the main compartment.

[0006] According to an embodiment of this application, the backscatter imaging device further includes: a main moving part connected to a main body and configured to provide a main moving path to switch the main body between a first target position and a second target position; and N auxiliary moving parts connected to N auxiliary bodies respectively, wherein at least one auxiliary moving part is configured to provide at least one auxiliary moving path to move at least one auxiliary body to or away from the first target position.

[0007] According to an embodiment of this application, at least one auxiliary moving part is configured to move at least one auxiliary part to the first target position in response to detecting that the main body has left the first target position; or, in response to detecting that the main body has moved to the first target position, at least one auxiliary part leaves the first target position.

[0008] According to an embodiment of this application, the first target position is higher than the ground. In the first inspection state, at least one auxiliary cabin is located in a ground pit, and the main cabin is located above the ground pit and is higher than the ground. In the second inspection state, at least one auxiliary moving part includes a lifting mechanism configured to move at least one auxiliary cabin from the ground pit to the first target position and be higher than the ground. The main moving part is configured to switch the main cabin from the first target position to the second target position.

[0009] According to an embodiment of this application, the main moving part includes a first guide rail perpendicular to the ground, and at least one auxiliary moving part includes at least one second guide rail parallel to the ground; wherein, the first guide rail is connected to the main body and configured to provide a main moving path to allow the main body to switch between a first target position and a second target position; at least one second guide rail provides at least one auxiliary moving path to allow at least one auxiliary body to move to or away from the first target position.

[0010] According to an embodiment of this application, the main cabin is also provided with heat dissipation fins that act on the radiation source. The heat dissipation fins are made of shape memory alloy and are configured to be in a contracted state when the temperature of the radiation source is less than a first threshold and in an expanded state when the temperature of the radiation source is greater than the first threshold.

[0011] According to an embodiment of this application, the main cabin is further provided with at least one of the following: a heater configured to activate the heating function when the temperature of the radiation source is less than a second threshold; an air conditioner configured to activate the cooling function when the temperature of the radiation source is greater than a third threshold; a thermal insulation layer attached to the inner or outer wall of the main cabin; and a shielding layer serving as a wall of the main cabin, or attached to at least one of the inner and outer walls of the main cabin to shield radiation.

[0012] According to an embodiment of this application, in the first inspection state, the auxiliary backscatter detector in any auxiliary compartment stops detecting backscatter signals.

[0013] According to an embodiment of this application, the main cabin and the N auxiliary cabins are each sealed independent spaces.

[0014] According to the backscatter imaging device provided in this application, efficient and comprehensive detection of target objects of different sizes is achieved through switchable inspection states and multi-compartment collaborative working modes. For example, by adjusting the position of the main compartment and flexibly deploying the auxiliary compartments, the detection range and adaptability are expanded, enabling the simultaneous inspection of both small and large target objects. Furthermore, for large target objects, the fusion processing of signals from multiple detectors can eliminate blind spots in single-view detection, improving the detection rate of hidden objects inside complex structural targets. In addition, the modular compartment design improves the maintainability and expandability of the equipment, facilitating adjustments to the number and layout according to actual needs. Attached Figure Description

[0015] The above-mentioned contents, other objects, features and advantages of this application will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0016] Figure 1 This illustration schematically depicts an application scenario of a backscatter imaging device in a first inspection state according to an embodiment of this application.

[0017] Figure 2 This illustration schematically depicts an application scenario of a backscatter imaging device in a second inspection state according to an embodiment of this application.

[0018] Figure 3 A schematic diagram illustrating the placement of the auxiliary compartment at the first target position according to an embodiment of this application is shown.

[0019] Figure 4 This illustration schematically depicts an application scenario of a backscatter imaging device in a first inspection state according to another embodiment of this application;

[0020] Figure 5 This illustration schematically depicts an application scenario of a backscatter imaging device in a second inspection state according to another embodiment of this application;

[0021] Figure 6 A schematic front view of a backscatter imaging device according to an embodiment of this application is shown; Figure 7 A schematic side view of a backscatter imaging device according to an embodiment of this application is shown.

[0022] The reference numerals used in the above figures are as follows:

[0023] 110. First-class target object; 120. Backscatter imaging equipment; 121. Main cabin; 122. First auxiliary cabin; 123. Second auxiliary cabin; 210. Second-class target object; 410. First-class target object; 420. Backscatter imaging equipment; 421. Main cabin; 422. First auxiliary cabin; 423. Second auxiliary cabin; 430. Hydraulic lifting platform; 510. Second-class target object; 1. Main cabin; 2. Upper cabin; 3. Lower cabin; 11. X-ray source; 600. Backscatter imaging equipment; 12. X-ray machine high-voltage controller; 13. X-ray machine radiator; 21. Backscatter detector; 31. Flywheel; 41. Controller; 51. Air conditioner; 61. Insulation layer. Detailed Implementation

[0024] The embodiments of this application will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of this application. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of this application for ease of explanation. However, it will be apparent that one or more embodiments may be implemented without these specific details. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this application.

[0025] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The terms “comprising,” “including,” etc., as used herein indicate the presence of features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0026] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0027] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0028] Figure 1 The illustration schematically depicts an application scenario of a backscatter imaging device in a first inspection state according to an embodiment of this application. Figure 2 The illustration schematically depicts an application scenario of a backscatter imaging device in a second inspection state according to an embodiment of this application.

[0029] This application provides a backscatter imaging device 120, which has a first inspection state and a second inspection state. The backscatter imaging device 120 includes: a main chamber 121, configured to install an X-ray source and a main backscatter detector; and N auxiliary chambers, each of which is configured to install an auxiliary backscatter detector, where N is an integer greater than or equal to 1.

[0030] Among them, such as Figure 1 As shown, in the first inspection state, the main cabin 121 is placed at the first target position, the radiation source is configured to perform radiation scanning on the first type of target object 110, and the main backscatter detector is configured to receive the main backscatter signal of the first type of target object 110 to obtain the first radiation image.

[0031] like Figure 2 As shown, in the second inspection state, the main cabin 121 switches from the first target position to the second target position, at least one auxiliary cabin is placed in the first target position, the radiation source is configured to perform radiation scanning on the second type of target object 210, the main backscatter detector is configured to receive the main backscatter signal of the second type of target object 210, and at least one auxiliary backscatter detector in at least one auxiliary cabin is configured to receive at least one auxiliary backscatter signal of the second type of target object 210, wherein the main backscatter signal of the second type of target object 210 and at least one auxiliary backscatter signal are used to fuse to obtain a second radiation image.

[0032] In this embodiment, the size of the second type of target object 210 is larger than the size of the first type of target object 110, and the second target position is higher than the first target position above the ground. The dimensions in this embodiment may include at least one of the length, width, and height.

[0033] Exemplarily, the backscatter imaging device 120 may include one or more radiation sources, one or more primary backscatter detectors, electronics, and electronic devices located inside or outside the main cabin 121. Exemplarily, the radiation sources are configured to emit radiation rays (such as X-rays, gamma rays, etc.) to scan a target object; the primary backscatter detector is located on the same side of the target object as the radiation source and is configured to receive scattered rays reflected by the target object. The backscatter imaging device 120 may include one or more secondary backscatter detectors located within an auxiliary cabin, functioning identically to the primary backscatter detectors.

[0034] For example, an X-ray source can emit X-rays to scan a target object. A backscatter detector (primary or secondary) can use its sensitive volume to convert the X-rays reflected from the target object into photons, and then use its internally encapsulated photoelectric converter to convert the photons into pulsed electrical signals. The target object (first or second type) can include objects such as vehicles, containers, suitcases, or other items in a security screening scenario, or various materials in a materials analysis scenario. The target object can also include the human body, such as a person passing through a security checkpoint in a station, airport, or other public place. In some embodiments, the radiation source can also include a gamma-ray source or other radiation sources that can produce Compton scattering.

[0035] For example, electronic devices may include amplifiers and other devices used to amplify the pulsed electrical signals output by the backscatter detector. The electronic device may include one or more processors and a memory for storing one or more programs, wherein when executed by one or more processors, the processors perform data processing on the electronic signals to generate a first radiation image or a second radiation image. The radiation source, backscatter detector (primary or secondary), and electronic devices can be communicatively connected to the electronic device via a network to transmit data. The network may include various connection types, such as wired, wireless communication links, or fiber optic cables. The backscatter detector and electronic devices can be communicatively connected to transmit pulsed electrical signals.

[0036] For example, a beam modulation device, such as a beamforming device, can also be installed within the main cabin 121. The beamforming device is located between the X-ray source and the detector. The beamforming device is used to modulate the X-rays generated by the X-ray source into a rotating X-ray beam. The main backscatter detector is used to receive the X-rays backscattered from the target object after the X-ray beam modulated by the beamforming device irradiates the target object.

[0037] In some embodiments, the main cabin 121 and the N auxiliary cabins are each sealed, independent spaces. The first type of target object 110 may include a car, and the second type of target object 210 may include a truck with a cargo box. The main backscatter signal is the ray signal reflected from the target object and received by the main backscatter detector. The auxiliary backscatter signal is the ray signal reflected from the target object and received by the auxiliary backscatter detector.

[0038] like Figure 1In the first inspection state, only the main chamber 121 can be configured, utilizing its internal X-ray source and main backscatter detector for radiation imaging. In the second inspection state, the main chamber 121 and N auxiliary chambers are configured, utilizing the X-ray source and main backscatter detector within the main chamber 121, and the auxiliary backscatter detectors within the auxiliary chambers for radiation imaging. The auxiliary chambers may only contain auxiliary backscatter detectors. In the first inspection state, any auxiliary backscatter detector within an auxiliary chamber ceases detecting backscatter signals. The auxiliary backscatter detectors can operate only in the second inspection state. Signal fusion can employ algorithms such as weighted averaging, feature-level fusion, or decision-level fusion, optimized according to the location and characteristics of different detectors. This integrates information from detectors at different locations, eliminates blind spots and occlusion problems from a single viewpoint, generates a more comprehensive and clearer target image, and improves detection accuracy.

[0039] For example, at highway entrances or checkpoints, security checks are required for different types of vehicles. Traditional fixed-height security inspection equipment cannot simultaneously meet the inspection needs of both passenger cars and large trucks, and may have blind spots for large trucks. When a passenger car (first type of target object 110) enters the inspection area, the backscatter imaging device 120 switches to the first inspection state, with the main body 121 positioned at a lower first target position (e.g., 1.2 meters high). The radiation source rapidly scans the vehicle with moderate energy, and the main backscatter detector receives the backscatter signal to generate the first radiation image. When a large truck (second type of target object 210) enters, the backscatter imaging device 120 switches to the second inspection state, with the main body 121 raised to the second target position (e.g., 3.5 meters high). Simultaneously, one, two, or more auxiliary bodies are placed below the original position of the main body 121. Auxiliary bodies can also be placed to the left, right, and above the current position of the main body 121. The radiation source is adjusted to higher energy to penetrate the truck structure. Multi-angle signals from the main and auxiliary backscatter detectors are processed through a real-time fusion algorithm to generate a second radiation image, effectively eliminating detection blind spots and identifying contraband hidden in different parts of the vehicle. In some embodiments, a vehicle identification camera can be used to automatically determine the vehicle type and switch states.

[0040] According to embodiments of this application, efficient and comprehensive detection of target objects of different sizes is achieved through switchable inspection states and multi-cabin collaborative working modes. For example, by adjusting the position of the main cabin and flexibly deploying the auxiliary cabins, the detection range and adaptability are expanded, enabling the simultaneous inspection of both small and large target objects. Furthermore, for large target objects, the fusion processing of multi-detector signals can eliminate blind spots in single-view detection, improving the detection rate of hidden items inside complex structural targets. In addition, the modular cabin design improves the maintainability and expandability of the equipment, facilitating adjustments to the number and layout according to actual needs.

[0041] In some embodiments, refer to Figure 2 The N auxiliary compartments include a first auxiliary compartment 122 and a second auxiliary compartment 123. In the second inspection state, the first auxiliary compartment 122 is located above the main compartment 121, and the second auxiliary compartment 123 is placed at the first target position, located below the main compartment 121.

[0042] For example, when using backscatter imaging equipment to inspect vehicles, in order to inspect vehicles at different heights, it is necessary to change the target height of the X-ray generator while keeping the X-ray source angle constant. Figure 1 and Figure 2 As shown, if inspecting a small car, a single main module of the equipment is used. If the height of the vehicle being inspected increases, such as when inspecting a truck, an additional module is added above and below the main module, such as a first auxiliary module and a second auxiliary module. This not only increases the height of the target point of the X-ray generator inside the equipment, but also allows for the addition of backscatter detectors in both the upper and lower modules to collect more backscattered X-rays and more material information data, thereby improving the final image quality.

[0043] Figure 3 A schematic diagram illustrating the placement of the auxiliary compartment in a first target position according to an embodiment of this application is shown.

[0044] and Figure 2 The main hull shown has an auxiliary hull located below it, unlike the other hull. Figure 3 The diagram shows two auxiliary cabins positioned below the main cabin. It is understood that more auxiliary cabins can be placed, and one or more auxiliary cabins can be placed on top of the main cabin. In this embodiment, the space of the auxiliary cabins is smaller than the space of the main cabin, and the detection area of ​​the auxiliary backscatter detector is smaller than the detection area of ​​the main backscatter detector. The smaller detection area of ​​the auxiliary backscatter detector allows it to adapt to the limited space of the auxiliary cabins, while focusing more on high-precision detection of specific areas; multiple small auxiliary backscatter detectors working together can cover a wider range of angles, compensating for the blind spots of a single large main detector.

[0045] In some embodiments, the auxiliary compartment can be manually moved to any one of the upper, lower, left, or right sides of the main compartment, or it can be automatically moved to any one of the upper, lower, left, or right sides of the main compartment by a mechanical device.

[0046] In some embodiments, the backscatter imaging device further includes:

[0047] The main moving unit, connected to the main body, is configured to provide a main moving path to allow the main body to switch between a first target position and a second target position.

[0048] N auxiliary moving parts are connected to N auxiliary cabins respectively, wherein at least one auxiliary moving part is configured to provide at least one auxiliary moving path to move at least one auxiliary cabin to or away from the first target position.

[0049] The main moving part may include, for example, a hydraulic lifting platform, a lead screw lifting system, or a rack and pinion transmission mechanism. The main moving path is the path followed by the main cabin when the main moving part acts on it, such as a linear track perpendicular to the ground. The auxiliary moving part may include a slide rail system, a telescopic boom, or a set of wheels. The auxiliary moving path is the path followed by the auxiliary cabin when the auxiliary moving part acts on it, such as the slide rail path of a slide rail system laid along the ground. Electronic equipment can be used to control the individual movement of the main moving part and the auxiliary moving part, as well as their coordinated control.

[0050] For example, when a small car is detected about to enter the inspection area, the main moving unit, controlled by electronic equipment, lowers the main compartment along the main moving path to the first target position. Simultaneously, all auxiliary moving units, controlled by electronic equipment, move their auxiliary compartments along auxiliary moving paths to standby positions on either side of the inspection channel. The backscatter imaging device quickly completes the inspection and obtains the first radiometric image. When a truck is detected entering, the main moving unit first raises the main compartment along the main moving path to the second target position, freeing up space below the main compartment. Then, based on the vehicle size and inspection requirements, auxiliary compartments are selected, and their respective auxiliary moving units move along auxiliary moving paths to the first target position and above the main compartment. Once the auxiliary compartments reach the target position, their bottom locking mechanisms automatically engage with positioning pins on the ground rails. Then, the backscatter imaging device quickly completes the inspection, generating a complete second radiometric image through signal fusion.

[0051] According to embodiments of this application, automated motion control reduces human intervention, improves operational efficiency and ease of use, and can efficiently complete safety inspection tasks for various types of vehicles in different scenarios.

[0052] In some embodiments, at least one auxiliary moving part is configured to move at least one auxiliary part to the first target position in response to detecting that the main body has left the first target position; or, in response to detecting that the main body has moved to the first target position, at least one auxiliary part moves away from the first target position. This embodiment can control the auxiliary part or the main body via electronic devices.

[0053] For example, multiple proximity sensors are installed at the first target location and along the main cabin's return path to form a detection zone. Based on the sensor data received by the electronic equipment, the auxiliary cabin begins to move and evacuate when the main cabin enters the preset proximity zone (e.g., 5 meters from the first target location); when the main cabin enters the final positioning zone (e.g., 0.5 meters from the first target location), the auxiliary cabin has completely evacuated to a safe position. For example, when multiple auxiliary cabins move, they move sequentially according to a preset priority order, with the priority determined based on the target object type and inspection requirements.

[0054] According to embodiments of this application, automated switching without human intervention reduces the workload of operators, reduces the possibility of human error, and improves operational stability and reliability.

[0055] Figure 4 The illustration schematically depicts an application scenario of a backscatter imaging device in a first inspection state according to another embodiment of this application. Figure 5 The illustration schematically depicts an application scenario of a backscatter imaging device in a second inspection state according to another embodiment of this application.

[0056] In some embodiments, the first target location is above the ground.

[0057] like Figure 4 In the first inspection state, at least one auxiliary compartment is located in the ground depression, and the main compartment 421 is located above the ground depression and above the ground.

[0058] like Figure 5 In the second inspection state, at least one auxiliary moving part includes a lifting mechanism (such as a hydraulic lifting platform 430) configured to move at least one auxiliary cabin from the ground pit to the first target position and above the ground, and the main moving part (not shown in the figure) is configured to switch the main cabin 421 from the first target position to the second target position to detect the second type of target object 510.

[0059] For example, the first target position and the second target position are vertically aligned, with the main cabin 421 and its auxiliary cabins on its upper and lower sides stacked. A hydraulic lifting platform 430 is installed at the bottom of a ground recess, supporting the auxiliary cabins located below the main cabin 421. Exemplarily, the hydraulic lifting platform 430 may include a column-type lifting component, such as a telescopic column. The hydraulic lifting platform 430 may also include a suspended lifting component, which raises the main cabin 421 and its first and second auxiliary cabins 422 and 423 on its upper and lower sides via a suspension mechanism.

[0060] In some embodiments, a vertical guide rail can be provided on the inner wall of the recess, and guide wheels can be installed on both sides of the auxiliary compartment to drive the second auxiliary compartment 423 to rise out of the recess or descend into the recess. The main compartment 421 can be additionally connected to a vertical guide rail installed on the ground to avoid applying additional pressure to the auxiliary compartment below it.

[0061] According to the embodiments of this application, the three-dimensional spatial design significantly improves the space utilization of the equipment. Compared with the traditional planar layout, it can effectively save floor space and is suitable for security inspection sites with limited space. By using the auxiliary moving part to lift the auxiliary cabin from the ground to the working position, a rapid state switching is achieved, which improves the response speed and working efficiency of the equipment.

[0062] In some embodiments, the main moving part includes a first guide rail perpendicular to the ground, and at least one auxiliary moving part includes at least one second guide rail parallel to the ground.

[0063] The first guide rail is connected to the main cabin and is configured to provide the main movement path so that the main cabin can switch between the first target position and the second target position.

[0064] At least one second guide rail provides at least one auxiliary movement path to move at least one auxiliary cabin to or away from the first target position.

[0065] For example, the main cabin is equipped with rollers on its sides, which contact the first guide rail, and the top of the main cabin is connected to the hoisting structure. The hoisting structure switches between the first target position and the second target position by applying tension to or releasing the main cabin. The auxiliary cabin is equipped with rollers at its bottom and moves along the auxiliary movement path defined by the second guide rail laid on the ground.

[0066] According to embodiments of this application, the three-dimensional guide rail layout combining vertical and horizontal elements ensures that the movement paths of the main and auxiliary cabins do not interfere with each other, thus ensuring safety and smoothness during state switching.

[0067] In some embodiments, the main body 421 is also provided with heat dissipation fins (not shown in the figure) that act on the radiation source.

[0068] The heat dissipation fins are made of shape memory alloy and are configured to be in a contracted state when the temperature of the radiation source is below a first threshold and in an expanded state when the temperature of the radiation source is above the first threshold.

[0069] Shape memory alloys, such as nickel-titanium shape memory alloys, can recover their pre-set shape when the temperature changes, exhibiting a shape memory effect. Heat sink fins can be directly mounted on the outer shell of the X-ray source or contact the X-ray source through thermal interface materials such as thermally conductive silicone grease. The heat sink fins are designed with a folded structure, forming a compact stack in the contracted state and arranged in a fan-shaped or radial pattern in the unfolded state to maximize the heat dissipation area. The contracted state is the form of the heat sink fins at lower temperatures, where the distance between the fins is small or they are close together, resulting in a smaller overall heat dissipation area. The unfolded state is the form of the heat sink fins at higher temperatures, where the distance between the fins is larger or they are fully unfolded, resulting in a larger overall heat dissipation area. For example, if the first threshold is set to 60°C (for example only), when the X-ray source temperature exceeds 60°C, the heat sink fins begin to unfold to the unfolded state.

[0070] Because the main cabin contains multiple devices, such as radiation sources, main backscatter detectors, and radiation modulation devices, the heat they emit varies. For example, the radiation source emits a large amount of heat, resulting in a high local temperature in its location and an uneven overall temperature within the main cabin.

[0071] According to the embodiments of this application, specialized heat dissipation treatment can be provided for the main heat source, such as the radiation source, which solves the problem that traditional overall heat dissipation methods are difficult to cope with local high temperatures. Through the adaptive characteristics of shape memory alloy, the heat dissipation capacity can be dynamically adjusted according to local temperature changes. When the radiation source temperature rises, heat dissipation is automatically enhanced, and when the temperature drops, heat dissipation is automatically weakened, so that local high temperatures can be controlled. Moreover, the passive adaptive heat dissipation scheme does not require a complex control system and energy consumption, which simplifies the equipment structure.

[0072] Figure 6 A schematic front view of a backscatter imaging device according to an embodiment of this application is shown; Figure 7 A schematic side view of a backscatter imaging device according to an embodiment of this application is shown.

[0073] In some embodiments, the main cabin 1 is further provided with at least one of the following:

[0074] The heater (not shown in the figure) is configured to activate the heating function when the temperature of the radiation source is below a second threshold.

[0075] Air conditioner 51 is configured to activate the cooling function when the temperature of the radiation source exceeds the third threshold.

[0076] The insulation layer 61 is attached to the inner or outer wall of the main body 1.

[0077] A shielding layer (not shown in the figure) serves as a wall of the main body 1, or is attached to at least one of the inner and outer walls of the main body 1, to shield radiation.

[0078] The backscattering security inspection equipment features a compartmentalized structure, dividing the equipment into upper, middle, and lower compartments, as referenced. Figure 6 and Figure 7 The backscatter imaging device of this embodiment includes a main chamber 1, an upper auxiliary chamber 2, and a lower auxiliary chamber 3. The main chamber 1 contains an X-ray source 11, an X-ray machine high-voltage controller 12, an X-ray machine heat sink 13, a backscatter detector 21, an X-ray modulation device—flywheel 31, a controller 41, an air conditioner 51, and an insulation layer 61. The main chamber 1 can be used independently as a complete functional module, suitable for inspecting cars. The auxiliary chamber can only be equipped with an auxiliary backscatter detector and other auxiliary equipment. It is evident that adding the upper and lower chambers increases the beam height of the X-ray source 11 (with a fixed X-ray angle, the height increase depends on the height of the inspected vehicle and the detection distance), making it suitable for inspecting trucks. Extended backscatter detectors are installed in the upper and lower chambers to improve image quality.

[0079] The main cabin 1 is reinforced with insulation material as a thermal insulation layer 61, which is attached to the inner or outer wall of the main cabin 1 to reduce heat exchange with the outside. The upper and lower cabins 3 do not require additional insulation material. When the main cabin 1 operates outdoors as a separate module, it needs to be rainproof and dustproof, with a sealed enclosure and a protection rating of at least IP65. An insulation layer 61 is added to the inner layer of the outer shell of the cabin to ensure the equipment's insulation performance.

[0080] For example, in order to extend the lifespan of the backscattering device, the temperature inside the chamber can be kept above 15°C and below 35°C before the X-ray source 11 exits the beam (example only).

[0081] It is understandable that the X-ray source 11 is a key core component with high cost. X-rays are typically generated using an X-ray machine, where the X-ray tube is usually a glass or ceramic vacuum tube. When X-rays are emitted from a target point bombarded by electrons, the target point generates a large amount of heat, requiring a cooling device to cool the X-ray tube. If the internal environment of the equipment is harsh, with sudden temperature fluctuations, the X-ray tube may close its slits to allow air in, reducing the vacuum level and shortening the lifespan of the X-ray machine. During X-ray modulation, the motor drives the flywheel 31 to rotate, generating heat during operation. The controller 41 can be an industrial computer, PLC, or other electronic device, which also generates heat during operation. The backscatter detector 21 collects scattered X-rays and is a photoelectric conversion sensor. It typically generates very little heat and can operate over a wide temperature range, eliminating the need for a dedicated cooling device and allowing it to be placed outside the main equipment compartment.

[0082] For example, to ensure a stable internal operating environment, the main compartment 1 is equipped with a heater and an air conditioner 51 to regulate the internal temperature. When the equipment starts up, temperature and humidity sensors inside the main compartment 1 detect the temperature and humidity. When the equipment temperature is below 5°C (i.e., the second threshold, for example only), the heater is activated to heat the main compartment 1; when it is above 15°C, the heater stops working. When the temperature is above 35°C (i.e., the third threshold, for example only), the air conditioner 51 is activated to cool; when it is below 25°C, the air conditioner 51 stops cooling.

[0083] To prevent condensation inside the equipment, when the relative humidity is greater than 90%, the heater and air conditioner 51 work together to reduce the relative humidity to below 60% before the equipment can be used normally. If the relative humidity inside the chamber is higher than 90% when the equipment starts, the dehumidification process is initiated. Specifically, the heater first heats the temperature to above 35°C, at which point the air conditioner 51 starts cooling. During the cooling process, the air conditioner 51 discharges the condensate inside to the outside of the chamber, thus reducing the relative humidity inside. When the relative humidity falls below a certain value (e.g., set at 60%), the air conditioner 51 stops cooling, and the dehumidification process ends. In cases where the main chamber is a sealed space, the interior uses the air conditioner to exchange heat with the outside.

[0084] It is understandable that when the X-ray source angle is fixed, if a higher vehicle needs to be scanned, the target position of the X-ray source needs to be raised. The raised upper and lower parts can increase the number of backscatter detectors to receive more flying backscattered rays. If the X-ray source 11, X-ray modulation device, backscatter detector 21, controller 41 and other auxiliary functional equipment are all placed in the same cabin, it will result in an excessively large equipment size, which will not only increase the difficulty of transportation and installation, but also result in an excessively large heat dissipation area, which is not conducive to the heat preservation or cooling effect of the equipment.

[0085] According to the embodiments provided in this application, the modular design of the compartments facilitates the addition of extended detectors to adapt to vehicle security inspections at different heights, improving the adaptability to different vehicle security inspection scenarios. The compartment design also facilitates modular manufacturing and installation of the equipment, enabling mass production and reducing manufacturing costs. Depending on the application scenario, appropriate module combinations can be selected to further reduce manufacturing costs. When inspecting cars, a main compartment module with complete inspection functions is used; when inspecting trucks, a main compartment plus upper and lower compartment extended detector modules are used.

[0086] Furthermore, the compartmentalized design allows for temperature and humidity regulation within the main chamber, ensuring that the X-ray source, X-ray modulation device, backscatter detector, controller, and other auxiliary equipment operate within a specific temperature and humidity range, maintaining a stable operating environment and extending the lifespan of the equipment within the main chamber. The X-ray source, X-ray modulation device, and corresponding controller generate significant heat during operation; therefore, installing them within the same chamber allows for cooling using air conditioning. Similarly, this design facilitates heating in cold climates. Installing the extended detectors in the upper and lower compartments outside the main chamber not only achieves a modular design but also reduces the heat dissipation area of ​​the main chamber, resulting in better insulation in cold weather and reduced solar radiation heating in hot weather.

[0087] Return to reference Figure 6 and Figure 7 When installing a backscatter imaging device with an upper and lower chamber, the lower chamber, main chamber, and upper chamber are installed sequentially from bottom to top, reducing the difficulty of installation and construction. The X-ray source inside the equipment is a radiation-type device and requires radiation protection measures, such as using lead as a shielding layer. However, since the X-ray generator is installed inside the main chamber, only the main chamber needs to be equipped with relevant radiation protection measures.

[0088] Those skilled in the art will understand that the features described in the various embodiments of this application can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in this application. In particular, the features described in the various embodiments of this application can be combined and / or combined in various ways without departing from the spirit and teachings of this application. All such combinations and / or combinations fall within the scope of this application.

Claims

1. A backscatter imaging device, characterized in that, The backscatter imaging device includes a first inspection state and a second inspection state, comprising: The main cabin is configured to house the radiation source and the main backscatter detector; There are N auxiliary cabins, each configured to install an auxiliary backscatter detector, where N is an integer greater than or equal to 1; In the first inspection state, the main cabin is placed at the first target position, the radiation source is configured to perform radiation scanning on the first type of target object, and the main backscatter detector is configured to receive the main backscatter signal of the first type of target object to obtain the first radiation image. In the second inspection state, the main cabin switches from the first target position to the second target position, at least one auxiliary cabin is placed at the first target position, the radiation source is configured to perform radiation scanning on the second type of target object, the main backscatter detector is configured to receive the main backscatter signal of the second type of target object, and at least one auxiliary backscatter detector in the at least one auxiliary cabin is configured to receive at least one auxiliary backscatter signal of the second type of target object, wherein the main backscatter signal and at least one auxiliary backscatter signal of the second type of target object are used to fuse to obtain a second radiation image; The second type of target object is larger than the first type of target object, and the second target position is higher than the first target position above the ground.

2. The device according to claim 1, characterized in that, The N auxiliary compartments include a first auxiliary compartment and a second auxiliary compartment. In the second inspection state, the first auxiliary compartment is located above the main compartment, and the second auxiliary compartment is placed at the first target position, located below the main compartment.

3. The device according to claim 1 or 2, characterized in that, The backscatter imaging device also includes: A main moving unit, connected to the main cabin, is configured to provide a main moving path that allows the main cabin to switch between a first target position and a second target position; N auxiliary moving parts are respectively connected to the N auxiliary cabins, wherein at least one auxiliary moving part is configured to provide at least one auxiliary moving path to move the at least one auxiliary cabin to or away from the first target position.

4. The device according to claim 3, characterized in that, The at least one auxiliary moving part is configured to move to the first target position in response to detecting that the main body has left the first target position; or, in response to detecting that the main body has moved to the first target position, to move away from the first target position.

5. The device according to claim 3, characterized in that, The first target position is higher than the ground. In the first inspection state, at least one auxiliary cabin is located in a ground depression, and the main cabin is located above the ground depression and is higher than the ground. In the second inspection state, the at least one auxiliary moving part includes a lifting mechanism configured to move the at least one auxiliary cabin from the ground pit to the first target position, which is higher than the ground, and the main moving part is configured to switch the main cabin from the first target position to the second target position.

6. The device according to claim 3, characterized in that, The main moving part includes a first guide rail perpendicular to the ground, and the at least one auxiliary moving part includes at least one second guide rail parallel to the ground; The first guide rail is connected to the main cabin and is configured to provide a main movement path so that the main cabin can switch between the first target position and the second target position. The at least one second guide rail provides at least one auxiliary movement path to move the at least one auxiliary cabin to or away from the first target position.

7. The device according to claim 1, characterized in that, The main cabin is also equipped with heat dissipation fins that act on the radiation source. The heat dissipation fins are made of shape memory alloy and are configured to be in a contracted state when the temperature of the radiation source is less than a first threshold and in an expanded state when the temperature of the radiation source is greater than the first threshold.

8. The device according to claim 1 or 7, characterized in that, The main cabin also contains at least one of the following: The heater is configured to activate the heating function when the temperature of the radiation source is less than a second threshold. The air conditioner is configured to activate its cooling function when the temperature of the radiation source exceeds a third threshold. The insulation layer is attached to the inner or outer wall of the main body; A shielding layer, serving as a wall of the main cabin, or attached to at least one of the inner and outer walls of the main cabin, to shield radiation.

9. The device according to claim 1, characterized in that, In the first inspection state, the auxiliary backscatter detector in any auxiliary compartment stops detecting backscatter signals.

10. The device according to claim 1, characterized in that, The main cabin and the N auxiliary cabins are each sealed, independent spaces.

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