Detection device based on backscatter imaging and target localization method

Abstract

This application relates to a detection device and a target localization method based on backscatter imaging. Based on this application, the detector array used for imaging the detection space includes, in addition to a first detector array based on backscatter imaging, a second detector array with a different ray receiving angle than the first detector array. The angular plane containing the angular difference between the ray receiving angles of the first and second detector arrays intersects with the array plane of the detector array. When a target substance appears in the detection space, based on the imaging position of the target substance in a localization reference direction parallel to the intersection of the angular plane and the array plane, and the position transformation parameter associated with the angular difference, the depth position of the target substance in the spatial depth direction intersecting the array plane can be determined, thereby helping to improve the localization efficiency of target localization based on backscatter imaging.

Description

Technical Field

[0001] This application relates to backscatter imaging technology, and in particular to a detection device based on backscatter imaging and a target localization method applicable to backscatter imaging. Background Technology

[0002] Detection rays such as X-rays can be used to perform transmission imaging on objects such as packages. The intensity of the rays will decrease after penetrating the object. The intensity of the rays after the decrease can be characterized by the pixel values ​​in the transmission image obtained by the transmission imaging detector, so as to observe the internal material of the object through the transmission image.

[0003] In addition to a portion of the X-ray beam penetrating the object being tested, another portion may be backscattered within the internal material of the object. The backscattering angle can range from 0 to 180°. Moreover, if the internal material contains substances with low atomic numbers, the backscattering imaging effect is even more pronounced.

[0004] Because many dangerous substances that endanger personal safety, such as drugs and explosives, are low atomic number substances, backscatter imaging is commonly used in the field of public safety protection to detect whether the object being tested contains such dangerous substances. This involves deploying the radiation source that generates the detection radiation and the detector array that receives the backscattered radiation on the same side of the detection space where the object is located. Furthermore, since these dangerous substances can induce strong backscattering, the backscattered images obtained from backscatter imaging can have a "highlighting" effect on these dangerous substances.

[0005] When a hazardous substance is identified in the detection space using backscattered images, the inspection personnel must quickly proceed to the site where the detection space is deployed to conduct a hazard assessment of the object containing the hazardous substance. However, during the hazard assessment process, it is difficult for the inspection personnel to quickly locate the aforementioned hazardous substance inside the object. This is because, even if the inspection personnel refer to the image position of the "highlighted" area in the backscattered image, they can only roughly infer the planar position of the hazardous substance inside the object in the direction parallel to the array plane of the detector array, but cannot infer the depth position of the hazardous substance inside the object in the direction intersecting with the array plane of the detector array. Consequently, the assessment efficiency is low.

[0006] As can be seen above, how to improve the positioning efficiency of target localization based on backscatter imaging has become a technical problem to be solved in the existing technology. Summary of the Invention

[0007] In view of this, embodiments of this application provide a detection device based on backscatter imaging and a target localization method, which helps to improve the localization efficiency of target localization based on backscatter imaging.

[0008] In one embodiment of this application, a detection device based on backscatter imaging includes:

[0009] A radiation source, used to generate detection radiation into the detection space;

[0010] The detector array includes a first detector array and a second detector array, wherein the first detector array is used to perform backscatter imaging of the detection space using the detection rays received from the detection space at a first ray receiving angle, and the second detector array is used to perform backscatter imaging or transmission imaging of the detection space using the detection rays received from the detection space at a second ray receiving angle. The imaging data generated by the first detector array and the second detector array imaging the detection space is used to generate a detection image, and there is an angular difference between the first ray receiving angle and the second ray receiving angle.

[0011] The processor component is used to identify target substances in the detected image, and is also used to:

[0012] Based on the image position information of the target substance in the detection image, the imaging position of the target substance in the positioning reference direction of the detector array is determined. The angular plane where the angle difference is located intersects with the array plane of the detector array, and the positioning reference direction is parallel to the line of intersection between the angular plane and the array plane of the detector array.

[0013] Based on the imaging position and the preset position conversion parameters, the depth position of the target substance in the spatial depth direction of the detection space is determined, wherein the spatial depth direction intersects the array plane, the spatial depth direction is parallel to the angular plane, and the position conversion parameters are related to the angle difference.

[0014] In some examples, optionally, the processor component is specifically configured to: determine the array coordinate position of the target detector in the detector array that images the target material in the positioning reference direction based on the image position information of the target material contained in the imaging data, the array coordinate position being used to characterize the imaging position, and the positioning reference direction including one of the row and column directions of the detector array parallel to the corner plane; and determine the depth position based on the array coordinate position and the position transformation parameters.

[0015] In some examples, optionally, the position transformation parameters include: a planar geometric relationship between any coordinate position in the positioning reference direction and the projection position of the spatial position of the target material in the angular plane, wherein the positioning reference direction includes a direction parallel to the angular plane in the row and column directions of the first detector array and the second detector array, and the planar geometric relationship is associated with the first ray receiving angle and the second ray receiving angle; the processor component is specifically configured to: determine the depth position based on the array coordinate position of the target detector in the first detector array and the second detector array that images the target material in the positioning reference direction, and the planar geometric relationship.

[0016] In some examples, optionally, the array planes of the first detector array and the second detector array are parallel to each other, the spatial depth direction is perpendicular to the array planes of the first detector array and the second detector array, the row directions of the first detector array and the second detector array are both parallel to a first spatial direction, the relative position of the target substance and the detection device in the first spatial direction is fixed, the intersection line of the angular plane and the array planes of the first detector array and the second detector array is parallel to the row directions of the first detector array and the second detector array, the positioning reference direction includes the row directions of the first detector array and the second detector array, and the array coordinate position includes: the first row coordinate position of the first target detector in the first detector array that images the target substance, and the second row coordinate position of the second target detector in the second detector array that images the target substance; the processor component is specifically configured to: determine the depth position based on the first row coordinate position, the second row coordinate position, and the planar geometry.

[0017] In some examples, optionally, the first detector array is configured to receive a first beam of the detection ray at a first ray receiving angle, and the second detector array is configured to receive a second beam of the detection ray at a second ray receiving angle. The angle information includes first angle information of the first ray receiving angle and second angle information of the second ray receiving angle. The planar geometric relationship includes: a base-height transformation relationship of a virtual triangle in the angular plane, the virtual triangle having a base parallel to the positioning reference direction and a vertex opposite the base, the two base angles of the base being associated with angle values ​​of the first ray receiving angle and the second ray receiving angle, the vertex representing the projection position of the target material in the angular plane, and the base-height transformation relationship representing the dimensional relationship between the side length of the base and the height of the vertex relative to the base. The processor component is specifically configured to: determine the side length of the base based on the first row coordinate position and the second row coordinate position; determine the height of the vertex of the virtual triangle relative to the base based on the side length of the base and the dimensional relationship; and determine the depth position based on the height of the vertex relative to the base.

[0018] In some examples, optionally, the first detector array and the second detector array are staggered in a second spatial direction perpendicular to the first spatial direction, the target substance and the detection device move relative to each other in the second spatial direction, the array planes of the first detector array and the second detector array are aligned in the same direction, and the second detector array is configured to perform backscatter imaging of the detection space; the processor component is specifically configured to determine the side length of the bottom edge based on the position difference between the first row coordinate position and the second row coordinate position.

[0019] In some examples, optionally, the first detector array is equipped with a first collimating member, and the second detector array is equipped with a second collimating member. The first collimating member has a first collimating channel inclined relative to the array plane of the first detector array at a first ray receiving angle, and the second collimating member has a second collimating channel inclined relative to the array plane of the second detector array at a second ray receiving angle. The first ray beam includes scattered rays from the detection space reflected to the first detector array through the first collimating channel, and the second ray beam includes scattered rays from the detection space reflected to the second detector array through the second collimating channel.

[0020] In some examples, optionally, the first detector array and the second detector array are arranged at intervals in the spatial depth direction, facing each other across the detection space, and the second detector array is configured to perform transmission imaging of the detection space; the processor component is specifically configured to: determine a target angle value of one base angle of the virtual triangle associated with the second ray receiving angle based on the second row coordinate position, the second ray receiving angle including different angle values ​​corresponding to multiple detectors in the row direction of the second detector array, and the target angle value is associated with the angle value corresponding to the second ray receiving angle at the second target detector; determine the side length of the base when the base angle of the virtual triangle associated with the second ray receiving angle is the target angle value based on the positional offset of the first row coordinate position compared with a reference row coordinate position, wherein the reference row coordinate position is the projection position of the ray source in the first detector array along the spatial depth direction.

[0021] In some examples, optionally, the first detector array is equipped with a first collimating member, the first collimating channel of the first collimating member being inclined relative to the array plane of the first detector array at a first ray receiving angle, the first ray beam including scattered rays from the detection ray passing through the first collimating channel, the second ray receiving angle being associated with the emission angle at which the ray source generates the detection ray, and the second ray beam including scattered rays from the transmitted ray penetrating the detection space.

[0022] In some examples, optionally, the position transformation parameters include: a position mapping relationship between any coordinate position in the positioning reference direction and a calibration position in the spatial depth direction, wherein the positioning reference direction is inclined relative to the spatial depth direction, and the position mapping relationship is associated with the first ray receiving angle or the second ray receiving angle; the processor component is specifically configured to: based on the position mapping relationship, determine the calibration position corresponding to the array coordinate position of the target detector in the first detector array or the second detector array that images the target material in the positioning reference direction as the depth position.

[0023] In some examples, optionally, the first detector array and the second detector array are staggered in a second spatial direction perpendicular to the first spatial direction. The target material and the detection device move relative to each other in the second spatial direction. The array plane of the second detector array is tilted about the first spatial direction relative to the spatial depth direction, and the tilt angle of the array plane of the detector array relative to the spatial depth direction is associated with the second ray receiving angle. The second detector array is a planar array containing at least two rows of detectors. The intersection of the corner plane and the array plane of the second detector array is parallel to the column direction of the second detector array. The row direction of the second detector array is parallel to the first spatial direction. The positioning reference direction is the column direction of the second detector array. The array coordinate position includes the column coordinate position of the second target detector in the second detector array that images the target material. The processor component is specifically configured to determine the calibration position corresponding to the column coordinate position in the spatial depth direction as the depth position based on the position mapping relationship.

[0024] In some examples, optionally, the first detector array is equipped with a first collimating member, and the second detector array is equipped with a second collimating member. The first collimating channel of the first collimating member is perpendicular to the array plane of the first detector array, and the second collimating channel of the second collimating member is perpendicular to the array plane of the second detector array. The first X-ray beam includes scattered X-rays from the detection space reflected to the first detector array through the first collimating channel, and the second X-ray beam includes scattered X-rays from the detection space reflected to the second detector array through the second collimating channel.

[0025] In some examples, optionally, the array plane is parallel to a first spatial direction, the relative position of the target material and the detection device in the first spatial direction is fixed, the target material and the detection device move relative to each other in a second spatial direction perpendicular to the first spatial direction, and the spatial depth direction is a third spatial direction perpendicular to both the first and second spatial directions; the processor component is further configured to: determine a first planar position of the target material in the first spatial direction based on the imaging position; and / or, determine a second planar position of the target material in the second spatial direction based on a unit offset step of the relative movement of the target material and the detector array in the second spatial direction, and the cumulative number of line scan bar images included in the imaging data before the target material is detected.

[0026] In another embodiment of this application, a target localization method includes:

[0027] Based on the image position information of the target substance appearing in the detection space in the detection image, the imaging position of the target substance in the positioning reference direction of the detector array is determined. The detection image is generated based on the imaging data generated by the detector array imaging the detection space. The detector array includes a first detector array and a second detector array. The first detector array is used to perform backscatter imaging of the detection space using the detection rays received from the detection space at a first ray receiving angle. The second detector array is used to perform backscatter imaging or transmission imaging of the detection space using the detection rays received from the detection space at a second ray receiving angle. There is an angular difference between the first ray receiving angle and the second ray receiving angle. The angular plane where the angular difference is located intersects with the array plane of the detector array. Furthermore, the positioning reference direction is parallel to the line of intersection between the angular plane and the array plane.

[0028] Based on the imaging position and the preset position conversion parameters, the depth position of the target substance in the spatial depth direction of the detection space is determined, wherein the spatial depth direction intersects with the array plane of the detector array, the spatial depth direction is parallel to the angular plane, and the position conversion parameters are related to the angle difference.

[0029] Optionally, in some examples, determining the imaging position of the target substance in the positioning reference direction of the detector array based on the image position information of the target substance appearing in the detection space in the detection image includes: determining the array coordinate position of the target detector in the detector array that images the target substance in the positioning reference direction based on the image position information, wherein the array coordinate position is used to characterize the imaging position, and the positioning reference direction includes one of the row and column directions of the detector array that is parallel to the corner plane; determining the depth position of the target substance in the spatial depth direction of the detection space based on the imaging position and a pre-set position transformation parameter includes: determining the depth position based on the array coordinate position and the position transformation parameter.

[0030] In some examples, optionally, the position transformation parameters include: a planar geometric relationship between any coordinate position in the positioning reference direction and the projection position of the spatial position of the target material in the angular plane, the planar geometric relationship being associated with the first ray receiving angle and the second ray receiving angle; and determining the depth position based on the array coordinate position and the position transformation parameters includes: determining the depth position based on the array coordinate position of the target detectors imaging the target material in the first detector array and the second detector array in the positioning reference direction, and the planar geometric relationship.

[0031] In some examples, optionally, the array planes of the first detector array and the second detector array are parallel to each other, the spatial depth direction is perpendicular to the array planes of the first detector array and the second detector array, the row directions of the first detector array and the second detector array are both parallel to the first spatial direction, the relative position of the target substance and the detection device in the first spatial direction is fixed, the intersection line of the angular plane and the array planes of the first detector array and the second detector array is parallel to the row directions of the first detector array and the second detector array, the positioning reference direction includes the row directions of the first detector array and the second detector array, and the array coordinate position includes: the first row coordinate position of the first target detector in the first detector array that images the target substance, and the second row coordinate position of the second target detector in the second detector array that images the target substance; determining the depth position based on the array coordinate position and the planar geometry includes: determining the depth position based on the first row coordinate position, the second row coordinate position, and the planar geometry.

[0032] In some examples, optionally, the planar geometric relationship includes: a base-height transformation relationship of a virtual triangle in the angular plane, the virtual triangle having a base parallel to the positioning reference direction and a vertex opposite the base, the two base angles of the base being associated with the angle values ​​of the first ray receiving angle and the second ray receiving angle respectively, the vertex being used to characterize the projection position of the target material in the angular plane, and the base-height transformation relationship being used to characterize the dimensional relationship between the side length of the base and the height of the vertex relative to the base; determining the depth position based on the first row coordinate position and the second row coordinate position, and the planar geometric relationship includes: determining the side length of the base based on the first row coordinate position and the second row coordinate position; determining the height of the vertex of the virtual triangle relative to the base based on the side length of the base and the dimensional relationship; and determining the depth position based on the height of the vertex relative to the base.

[0033] In some examples, optionally, the first detector array and the second detector array are staggered in a second spatial direction perpendicular to the first spatial direction, the target substance and the detection device move relative to each other in the second spatial direction, the array planes of the first detector array and the second detector array are aligned in the same direction, and the second detector array is configured to perform backscatter imaging of the detection space; determining the side length of the bottom edge based on the first row coordinate position and the second row coordinate position includes: determining the side length of the bottom edge based on the position difference between the first row coordinate position and the second row coordinate position.

[0034] In some examples, optionally, the first detector array and the second detector array are arranged at intervals in the spatial depth direction, facing each other across the detection space, and the second detector array is configured to perform transmission imaging of the detection space; determining the side length of the base based on the first row coordinate position and the second row coordinate position includes: determining a target angle value of one side base angle of the virtual triangle associated with the second ray receiving angle based on the second row coordinate position, the second ray receiving angle including different angle values ​​corresponding to multiple detectors in the row direction of the second detector array, and the target angle value being associated with the angle value corresponding to the second ray receiving angle at the second target detector; determining the side length of the base when the side base angle of the virtual triangle associated with the second ray receiving angle is the target angle value based on the positional offset of the first row coordinate position in the first array plane compared to a reference row coordinate position, wherein the reference row coordinate position is the projection position of the ray source in the first array plane along the spatial depth direction.

[0035] Optionally, in some examples, the position transformation parameter includes: a position mapping relationship between any coordinate position in the positioning reference direction and a calibration position in the spatial depth direction, and the position mapping relationship is associated with the first ray receiving angle or the second ray receiving angle; determining the depth position based on the array coordinate position and the position transformation parameter includes: determining the calibration position corresponding to the array coordinate position of the target detector in the first detector array or the second detector array that images the target material in the positioning reference direction as the depth position based on the position mapping relationship.

[0036] In some examples, optionally, the first detector array and the second detector array are staggered in a second spatial direction perpendicular to the first spatial direction. The target material and the detection device move relative to each other in the second spatial direction. The array plane of the second detector array is tilted about the first spatial direction relative to the spatial depth direction, and the tilt angle of the array plane of the detector array relative to the spatial depth direction is associated with the second ray receiving angle. The second detector array is a planar array containing at least two rows of detectors. The intersection of the corner plane and the array plane of the second detector array is parallel to the column direction of the second detector array. The positioning reference direction is the column direction of the second detector array. The array coordinate position includes: the column coordinate position of the second target detector in the second detector array that images the target material. The first detector array and the second detector array are staggered in the second spatial direction perpendicular to the first spatial direction. The target material and the detection device move relative to each other in the second spatial direction. The array plane of the second detector array is tilted relative to the spatial depth direction around the first spatial direction. The tilt angle of the array plane of the detector array relative to the spatial depth direction is related to the second ray receiving angle. The second detector array is a planar array containing at least two rows of detectors. The intersection line of the corner plane and the array plane of the second detector array is parallel to the column direction of the second detector array. The positioning reference direction is the column direction of the second detector array. The array coordinate position includes the column coordinate position of the second target detector in the second detector array that images the target material. The step of determining the calibration position corresponding to the array coordinate position in the spatial depth direction as the depth position based on the position mapping relationship includes: determining the calibration position corresponding to the column coordinate position in the spatial depth direction as the depth position based on the position mapping relationship.

[0037] In some examples, optionally, the array plane is parallel to a first spatial direction, the relative position of the target material, the radiation source, and the detector array in the first spatial direction is fixed, the target material, the radiation source, and the detector array move relative to each other in a second spatial direction perpendicular to the first spatial direction, and the spatial depth direction is a third spatial direction perpendicular to both the first and second spatial directions; the target localization method further includes: determining a first planar position of the target material in the first spatial direction based on the imaging position; and / or, determining a second planar position of the target material in the second spatial direction based on a unit offset step of the relative movement of the target material and the detector array in the second spatial direction, and the cumulative number of line scan bar images included in the imaging data before the target material is detected.

[0038] In another embodiment of this application, a target positioning device includes:

[0039] An imaging position determination module is used to determine the imaging position of the target substance in the detection image based on the image position information of the target substance appearing in the detection space in the detection image. The detection image is generated based on imaging data generated by the detector array imaging the detection space. The detector array includes a first detector array and a second detector array. The first detector array is used to perform backscatter imaging of the detection space using the detection rays received from the detection space at a first ray receiving angle. The second detector array is used to perform backscatter imaging or transmission imaging of the detection space using the detection rays received from the detection space at a second ray receiving angle. There is an angular difference between the first ray receiving angle and the second ray receiving angle. The angular plane where the angular difference occurs intersects with the array plane of the detector array. Furthermore, the positioning reference direction is parallel to the line of intersection between the angular plane and the array plane.

[0040] A depth positioning module is used to determine the depth position of the target substance in the spatial depth direction of the detection space based on the imaging position and a preset position conversion parameter, wherein the spatial depth direction intersects with the array plane of the detector array, the spatial depth direction is parallel to the angular plane, and the position conversion parameter is related to the angle difference.

[0041] In another embodiment of this application, a non-transitory computer-readable storage medium is provided, wherein instructions are stored that, when executed by a processor, cause the processor to perform the target localization method described in the foregoing embodiments.

[0042] Based on the above embodiments, the detector array for imaging the detection space includes, in addition to a first detector array based on backscatter imaging, a second detector array with a different ray receiving angle than the first detector array. The angular plane containing the angular difference between the ray receiving angles of the first and second detector arrays intersects with the array plane of the detector array. When a target substance appears in the detection space, based on the image position information associated with the imaging position of the target substance in the positioning reference direction, and the position transformation parameter associated with the angular difference, the depth position of the target substance in the spatial depth direction intersecting the array plane can be determined, thereby helping to improve the positioning efficiency of target localization based on backscatter imaging. Attached Figure Description

[0043] The following figures are for illustrative purposes only and do not limit the scope of this application:

[0044] Figure 1 This is a schematic diagram of the detection device based on backscatter imaging in the embodiments of this application;

[0045] Figure 2 This is a schematic diagram of the detector array layout of a first device example of the detection device in the embodiments of this application;

[0046] Figure 3 This is a schematic diagram illustrating the principle of depth positioning based on the detector array layout of the first device example.

[0047] Figure 4 This is a schematic diagram of the detector array layout of a second device example of the detection device in the embodiments of this application;

[0048] Figure 5 This is a schematic diagram illustrating the principle of depth positioning based on the detector array layout of the second device example.

[0049] Figure 6 This is a schematic diagram of the detector array layout and depth positioning principle of the third device example of the detection device in the embodiments of this application;

[0050] Figure 7 This is an exemplary flowchart of a target localization method in an embodiment of this application;

[0051] Figure 8 This is an exemplary flowchart of a target positioning device according to an embodiment of this application. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided with reference to the accompanying drawings and embodiments.

[0053] Figure 1 This is a schematic diagram of the detection device in an embodiment of this application. Please refer to [link / reference]. Figure 1 In embodiments of this application, the detection device may include an X-ray source 100, a detector array 200, and a processor assembly 300.

[0054] The radiation source 100 is used to generate detection radiation such as X-rays into the detection space 400.

[0055] In some instances, the detection device in this application embodiment can be a security inspection device with a conveying mechanism for conveying the object to be inspected. In this case, the detection space 400 can be located inside the housing space through which the conveying mechanism passes. For example, the security inspection device can include a lead housing and a conveying mechanism. The conveying mechanism is deployed to pass through the housing space inside the lead housing. The detection space 400 can be a spatial region in the housing space located above the bearing plane of the conveying mechanism. The radiation source 100 can be deployed inside the lead housing and can be located below the bearing plane of the conveying mechanism to generate detection radiation toward the spatial region above the bearing plane of the conveying mechanism.

[0056] In other instances, the detection device in this application embodiment can be a portable security inspection component including a mobile security scanner and a lead-containing barrier. The mobile security scanner can be a standalone device that is easy for inspection personnel to carry, or it can be a modular device integrated into a mobile device such as a mobile robot (e.g., integrated into the end of the arm of a mobile robot). In this case, the detection space 400 can be located next to the lead-containing barrier in a space that is convenient for placing the object to be inspected. Furthermore, the X-ray source 100 can be integrated into the mobile security scanner to generate detection rays into the space next to the lead-containing barrier when the mobile security scanner is facing the lead-containing barrier.

[0057] The detector array 200 may include a first detector array 210 and a second detector array 220, and both the first detector array 210 and the second detector array 220 are used to image the detection space 400 using the beam of X-rays in the detection X-rays received from the detection space 400.

[0058] The first detector array 210 is configured to backscatter image the detection space 400 on the same side as the X-ray source 100. That is, the first detector array 210 can be regarded as a backscatter detector array. Furthermore, if the detection device in this embodiment is the security inspection equipment mentioned above, the first detector array 210 arranged on the same side as the X-ray source 100 can be arranged together with the X-ray source 100 below the bearing plane of the conveying mechanism. If the detection device in this embodiment is a portable security inspection component including a mobile security inspection instrument and a lead-containing baffle, the first detector array 210 arranged on the same side as the X-ray source 100 can be integrated together with the X-ray source 100 in the mobile security inspection instrument.

[0059] The second detector array 220 can be configured to backscatter image the detection space 400 on the same side as the X-ray source 100, i.e., as Figure 1 As illustrated in the diagram; or, the imaging mode of the second detector array 220 may also differ from that shown in the diagram. Figure 1 As illustrated in the diagram, the second detector array 220 can also be configured to perform transmission imaging of the detection space on the opposite side of the X-ray source 100. The imaging mode of the second detector array 220 in the embodiments of this application is not limited.

[0060] In the embodiments of this application, regardless of the imaging mode configured for the second detector array 220, the ray receiving angle of the second detector array 220 to the ray beam differs from the ray receiving angle of the first detector array 210 to the ray beam; that is, there is an angular difference between the ray receiving angles of the first detector array 210 and the second detector array 220 to the ray beam. For example, as Figure 1 As shown, the first detector array 210 is configured to receive the first beam of radiation (i.e., the backscattered beam) in the detection radiation at a first radiation receiving angle θ1, and the second detector array 220 is configured to receive the second beam of radiation (i.e., the backscattered beam or the transmitted beam) in the detection radiation at a second radiation receiving angle θ2.

[0061] It is understood that the ray receiving angle described in the embodiments of this application refers to the deployment angle of the collimating channel used to limit the ray receiving range of the first array plane of the first detector array 210. Furthermore, whether it is the first ray beam received by the first detector array 210 at the first ray receiving angle θ1 or the second ray beam received by the second detector array 220 at the second ray receiving angle θ2, they are both scattered beams constrained within the size range of the corresponding collimating channel, rather than necessarily parallel beams whose incident angles are the same as the ray receiving angles of the corresponding collimating channel.

[0062] The angular difference between the first ray receiving angle θ1 of the first detector array 210 and the second ray receiving angle θ2 of the second detector array 220 for the ray beam can be in any plane in the detection space 400.

[0063] Assuming the spatial coordinate system of the detection space 400 includes a first spatial direction X, a second spatial direction Y, and a third spatial direction Z that are mutually perpendicular, the target material 550 and the detection device have a fixed relative position in the first spatial direction X, and the target material 550 and the detection device move relative to each other in the second spatial direction Y, which is perpendicular to the first spatial direction X. For example, if the detection device in this embodiment is the security inspection equipment mentioned above, then the first spatial direction X can be the width direction of the conveying mechanism, and the second spatial direction Y can be the conveying direction of the conveying mechanism through the lead-containing shell; if the detection device in this embodiment is a portable security inspection component including a mobile security inspection device and a lead-containing baffle, then the first spatial direction X can be perpendicular to the scanning operation direction of the mobile security inspection device, and the second spatial direction Y can be parallel to the scanning operation direction of the mobile security inspection device.

[0064] In the aforementioned spatial coordinate system, the first array plane of the first detector array 210 can be parallel to the XY plane jointly defined by the first spatial direction X and the second spatial direction Y. For example, if the detection device in this embodiment is the security inspection equipment mentioned above, then the XY plane can be the bearing plane of the conveying mechanism; if the detection device in this embodiment is a portable security inspection component including a mobile security inspection instrument and a lead-containing baffle, then the XY plane can be the scanning plane of the mobile security inspection instrument. In this case, the third spatial direction Z, which is perpendicular to both the first spatial direction X and the second spatial direction Y, can be regarded as the spatial depth direction of the detection space 400. Furthermore, the spatial depth direction (e.g., the third spatial direction Z) intersects with the array plane of the detector array 200. That is, the spatial depth direction (e.g., the third spatial direction Z) intersects with both the first array plane of the first detector array 210 and the second array plane of the second detector array 220. Moreover, the spatial depth direction (e.g., the third spatial direction Z) can at least be perpendicular to the first array plane of the first detector array 210 that is parallel to the XY plane.

[0065] In the aforementioned spatial coordinate system, the second array plane of the second detector array 220 can be parallel to the XY plane. Alternatively, the second array plane of the second detector array 220 can also be tilted relative to the aforementioned XY plane at a tilt angle of less than 90°. In this case, the second array plane of the second detector array 220 is tilted about the first spatial direction X relative to the spatial depth direction (e.g., the third spatial direction Z), and the aforementioned tilt angle can be associated with the second ray receiving angle θ2.

[0066] In the aforementioned spatial coordinate system, the aforementioned angular difference can be in the XZ plane, which is jointly defined by the first spatial direction X and the third spatial direction Z, or in the YZ plane, which is jointly defined by the second spatial direction Y and the third spatial direction Z. Regardless of whether the plane containing the angular difference is the XZ plane or the YZ plane, this plane can be considered as the angular plane containing the angular difference between the ray receiving angles of the first detector array 210 and the second detector array 220 for the ray beam. Furthermore, this angular plane intersects with the array plane of the detector array 200, that is, it intersects with both the first array plane of the first detector array 210 and the second array plane of the second detector array 220. This "intersection" can be generally understood as the angular plane intersecting with the unbounded plane containing the array planes of the detector array 200 (i.e., the first array plane and the second array plane). For example, if the angular plane is the XZ plane, then the line of intersection between the angular plane and the array plane of the detector array 200 can be parallel to the first spatial direction X; or, if the angular plane is the YZ plane, then the line of intersection between the angular plane and the array plane of the detector array 200 can be parallel to the second spatial direction Y.

[0067] The processor component 300 may include at least one of the following processing devices: CPU (central processing unit), logic device such as FPGA (Field-Programmable Gate Array), GPU (Graphics Processing Unit), and AI (Artificial Intelligence) processing unit.

[0068] The processor component 300 can be used to control the X-ray source 100 and generate a detection image based on the imaging data generated by the detector array 200 imaging the detection space 400, that is, the imaging data generated by the detector array 200 imaging the detection space 400 is used to generate the detection image.

[0069] In embodiments of this application, the imaging data generated by the detector array 200 may include first imaging data generated by the first detector array 210 and second imaging data generated by the second detector array 220. The detection image may include a first detection image (i.e., a backscattered image) generated based on the first imaging data and a second detection image (i.e., a backscattered image or a transmission image) generated based on the second imaging data.

[0070] If the first detector array 210 is a linear array, the imaging process of the first detector array 210 on the detection space 400 can be regarded as a line scanning process of the object 500 during its movement along the second spatial direction Y. In this case, a single frame image in the first imaging data can be a line scan bar graph, and each frame of the first detection image generated based on the first imaging data can be obtained by stitching together multiple frames of line scan bar graphs within a preset time window. If the first detector array 210 is a planar array, the imaging process of the first detector array 210 on the detection space 400 can be a single frame capture process. In this case, a single frame image in the first imaging data can be a two-dimensional image, and each frame of the first detection image generated based on the first imaging data can include at least one two-dimensional image within a preset time window.

[0071] The second detector array 220 can be a linear array or a planar array, and the second imaging data and the second detection image can be substantially the same as the first imaging data and the first detection image described above, which will not be repeated here.

[0072] The processor component 300 can also be used to identify target substance 550 in the detection image and thereby determine whether target substance 550 exists in the detection space 400. In embodiments of this application, the target substance 550 may include low atomic number substances such as hazardous substances hidden inside the object under inspection 500, and the identification of target substance 550 by the processor component 300 includes identifying target substance 550 in the first detection image and the second detection image.

[0073] Because the first detector array 210 and the second detector array 220 receive the detection rays at different angles, and because the detector sizes of the first detector array 210 and the second detector array 220 may be different, the shape, position, size, and other image features of the same target substance 550 will be different in the first detection image and the second detection image. To facilitate the identification of the same target substance in different detection images, in embodiments of this application, the process by which the processor component 300 identifies the target substance 550 in the first detection image and the second detection image may specifically include:

[0074] The first detection image and the second detection image are subjected to scale adaptation processing such as geometric registration and image scaling, and the first adapted image corresponding to the first detection image and the second adapted image corresponding to the second detection image are obtained respectively, so as to ensure that the same target material 550 has the same scale in the first adapted image and the second adapted image.

[0075] The first and second adapted images are used to identify the target material 550 to determine the contour region in the first and second adapted images used to characterize the same target material 550.

[0076] Based on the scale transformation relationship used in the scale adaptation process, the contour regions used to represent the same target substance 550 in the first and second adapted images are deduced in reverse, and the corresponding target regions in the first and second detection images are respectively represented by the target substances 550 identified in the first and second detection images.

[0077] In addition, at least one of the first detection image and the second detection image, or the fused image of the first adaptation image and the second adaptation image, can be used for visualization on the terminal device.

[0078] The processor component 300 is also used when identifying target substance 550 in the detection image:

[0079] Based on the image position information of the identified target substance 550 in the detection image, the imaging position of the target substance 550 in the positioning reference direction in the detector array 200 is determined. The positioning reference direction is parallel to the intersection of the aforementioned angular plane and the array plane of the detector array 200. For example, referring to the previous text, the positioning reference direction can be a first spatial direction X or a second spatial direction Y.

[0080] Based on the imaging position of the target material 550 in the positioning reference direction in the detector array 200 and the preset position conversion parameters, the depth position of the target material 550 in the spatial depth direction (e.g., the third spatial direction Z) of the detection space 400 is determined. The position conversion parameters are related to the angular difference between the first ray receiving angle θ1 and the second ray receiving angle θ2. Alternatively, the position conversion parameters can be considered to be related to at least one of the first ray receiving angle θ1 and the second ray receiving angle θ2.

[0081] Furthermore, the image position information of the target substance 550 in the detection image may include at least one of the first image position coordinates of the target substance 550 in the first image direction corresponding to the first spatial direction X, and the second image position coordinates of the target substance 550 in the second image direction corresponding to the second spatial direction Y. If the target substance 550 is characterized by the target region described above in the detection image (i.e., the first detection image and the second detection image), then the aforementioned first image position coordinates and second image position coordinates may be the feature positions of any region feature (e.g., the centroid) of the target region.

[0082] Based on the above embodiments, the detector array 200 for imaging the detection space includes, in addition to the first detector array 210 based on backscatter imaging, a second detector array 220 with a different ray receiving angle than the first detector array 210. The angular plane (e.g., the XZ plane or the YZ plane) containing the angular difference between the first ray receiving angle θ1 of the first detector array 210 and the second ray receiving angle θ2 of the second detector array 220 intersects the array plane of the detector array 200 (i.e., the first array plane of the first detector array 210 and the second array plane of the second detector array 220). Therefore, when a target substance 550 appears in the detection space 400, based on the image position information associated with the imaging position of the target substance 550 in the positioning reference direction (e.g., the first spatial direction X or the second spatial direction Z), and the position transformation parameter associated with the angular difference, the depth position of the target substance 550 in the spatial depth direction (e.g., the third spatial direction) intersecting with the array plane can be determined, thereby helping to improve the positioning efficiency of target positioning based on backscatter imaging.

[0083] In the embodiments of this application, the processor component 300 can convert the image position information of the target material 550 in the detection image into the array mapping position of the target material 550 in the detector array 200 based on the coordinate transformation relationship between the image coordinate system of the pre-calibrated detection image and the array coordinate system of the detector array 200, so as to use the array mapping position obtained by coordinate transformation to characterize the imaging position of the target material 550 in the positioning reference direction in the detector array 200.

[0084] The accuracy of the array mapping position is related to the parameter calibration in the coordinate transformation relationship. Therefore, if the depth position of the target material 550 in the spatial depth direction (e.g., the third spatial direction Z) of the detection space 400 is determined based on the array mapping position and the aforementioned position transformation parameters, a large number of parameter calibrations are required to ensure the accuracy of the depth position.

[0085] To simplify the parameter calibration required to achieve positioning accuracy, in the embodiments of this application, the array coordinate position of the target detector imaging the target substance 550 in the positioning reference direction can also be used to characterize the imaging position of the target substance 550 in the positioning reference direction of the detector array 200. For example, based on the positional correspondence between each pixel in the first and second detection images and each detector in the detector array 200, the detector corresponding to the pixel at the image coordinate position (e.g., the regional feature position of the target area) included in the image position information of the target substance 550 in the detection image can be used to determine the detector in the detector array 200 corresponding to the pixel at the image coordinate position. Here, the detector is the target detector imaging the target substance 550 in the detector array 200, and the array sorting number of the detector in the positioning reference direction of the detector array 200 can be used to characterize the array coordinate position of the target detector in the positioning reference direction.

[0086] To better understand the working principle of the detection device in the embodiments of this application, the following will provide examples of the first device, the second device, and the third device.

[0087] In the first, second, and third device examples, the imaging position of the target material 550 in the positioning reference direction of the detector array 200 is characterized by the array coordinate position of the target detector imaging the target material 550 in the positioning reference direction. In this case, the processor component 300 can be specifically used for:

[0088] Based on the image position information of the target substance 550 in the detection image, the array coordinate position of the target detector in the detector array 200 (i.e., the first detector array 210 and / or the second detector array 220) that images the target substance 550 is determined in the positioning reference direction. The array coordinate position is used to characterize the imaging position of the target substance 550 in the positioning reference direction in the detector array 200. The positioning reference direction includes one of the row and column directions of the detector array 200 that is parallel to the corner plane (i.e., parallel to the intersection of the aforementioned corner plane and the array plane of the detector array 200).

[0089] Based on the array coordinate position of the target detector in the detector array 200 that images the target material 550 in the positioning reference direction, and the position transformation parameters associated with the angle difference mentioned above, the depth position of the target material 550 in the spatial depth direction (e.g., the third spatial direction Z) of the detection space 400 is determined.

[0090] Furthermore, in the first device instance, the second device instance, and the third device instance, the deployment method of the first detector array 210 and the second detector array 220, as well as the imaging mode of the second detector array 220, may not be entirely the same. Therefore, the array coordinate position determined by the processor component 300 and the specific algorithm for determining the depth position by the processor component 300 may have different choices.

[0091] Figure 2 This is a schematic diagram of the detector array layout for a first example of the detection device in this application. Please refer to... Figure 2 In the first device example, the second detector array 220 can be configured to backscatter image the detection space 400 on the same side of the X-ray source 100. That is, the first device example is configured as a dual backscatter imaging device in which both the first detector array 210 and the second detector array 220 employ backscatter imaging. Furthermore, the first array plane of the first detector array 210 and the second array plane of the second detector array 220 are parallel to each other. For example, the first array plane of the first detector array 210 and the second array plane of the second detector array 220 are both parallel to the XY plane, and the spatial depth direction (i.e., the third spatial direction Z) is perpendicular to the first array plane of the first detector array 210 and the second array plane of the second detector array 220.

[0092] Specifically, such as Figure 2 As shown, in the first device example, the first detector array 210 and the second detector array 220 are staggered in the second spatial direction Y. The detection rays generated by the X-ray source 100 are collimated by the source-end collimating member and pass through the gap between the first detector array 210 and the second detector array 220 in a fan shape parallel to the XZ plane, heading towards the detection space. Furthermore, the first array plane of the first detector array 210 and the second array plane of the second detector array 220, which are parallel to each other, are arranged to be aligned in the same direction. When the relative position of the standard material 550 and the detection device in the first spatial direction X is fixed, the row directions of the first array plane of the first detector array 210 and the second array plane of the second detector array 220 are both parallel to the first spatial direction X.

[0093] In this configuration, the first detector array 210 is equipped with a first collimating member 610, and the second detector array 220 is equipped with a second collimating member 620. The first collimating channel of the first collimating member 610 is inclined relative to the first array plane of the first detector array 210 in a direction parallel to the XZ plane with a first ray receiving angle θ1. The second collimating channel of the second collimating member 620 is inclined relative to the second array plane of the second detector array 220 in a direction parallel to the XZ plane with a second ray receiving angle θ2. Thus, the ray receiving angles of the first collimating channel and the second collimating channel are constrained by the tilt angle of the first collimating member 610 relative to the first array plane and the tilt angle of the second collimating member 620 relative to the second array plane, respectively. Accordingly, the aforementioned first ray beam includes scattered rays from the detection space 400 reflected to the first detector array 210 through the first collimating channel constrained by the first ray receiving angle θ1, and the aforementioned second ray beam includes scattered rays from the detection space 400 reflected to the second detector array 220 through the second collimating channel constrained by the second ray receiving angle θ2.

[0094] Therefore, in the first device example, the angular plane containing the angular difference between the ray receiving angles of the first detector array 210 and the second detector array 220 is parallel to the XZ plane, and the intersection of this angular plane with the first array plane of the first detector array 210 and the second array plane of the second detector array 220 is parallel to the first spatial direction X.

[0095] Therefore, in the first device example, the aforementioned positioning reference direction includes the row direction of the first detector array 210 parallel to the first spatial direction X, and the row direction of the second detector array 220 parallel to the first spatial direction X. That is, for the imaging position of the target material 550 in the first detector array 210, the aforementioned positioning reference direction includes the row direction of the first detector array 210; and for the imaging position of the target material 550 in the second detector array 220, the aforementioned positioning reference direction includes the row direction of the second detector array 220.

[0096] Since the positioning reference direction in the first device example is parallel to the first spatial direction X, preferably, the first detector array 210 and the second detector array 220 can both be linear arrays including single-row detectors, and the row direction of the linear array is parallel to the first spatial direction X. In this case, each frame image included in the first imaging data generated by the first detector array 210 and the second imaging data generated by the second detector array 220 is a line scan bar graph. Furthermore, preferably, the size specifications of the first detector array 210 and the second detector array 220 are the same.

[0097] Based on such Figure 2 The position transformation parameters in the first device example of the detector array layout shown may include: any coordinate position in the positioning reference direction, and the planar geometric relationship between the spatial position of the target material 550 and the projection position in the angular plane (i.e., the XZ plane) where the angular difference between the ray receiving angles of the first detector array 210 and the second detector array 220 is located. This planar geometric relationship may be associated with the first ray receiving angle θ1 of the first detector array 210 and the second ray receiving angle θ2 of the second detector array.

[0098] Accordingly, the processor component 300 in the first device instance can be specifically configured as follows:

[0099] Based on the array coordinates of the target detectors in the first detector array 210 and the second detector array 220 that image the target material 550 in the positioning reference direction, and the aforementioned planar geometric relationship, the depth position of the target material 550 in the spatial depth direction (e.g., the third spatial direction Z) of the detection space 400 is determined.

[0100] Specifically, if, as described above, the positioning reference direction includes the row direction of the first detector array 210 and the second detector array 220, then the array coordinate position determined by the processor component 300 may include the first row coordinate position det_1_i (subscript i indicates the sorting position of the first target detector in the row direction of the first detector array 210) of the first target detector imaging the target material 550, and the second row coordinate position det_2_j (subscript j indicates the sorting position of the second target detector in the row direction of the second detector array 220) of the second target detector imaging the target material 550. Furthermore, the processor component 300 in the first device example may be specifically configured to: determine the depth position of the target material 550 in the spatial depth direction (e.g., the third spatial direction Z) of the detection space 400 based on the first row coordinate position det_1_i, the second row coordinate position det_2_j, and the aforementioned planar geometric relationship.

[0101] Figure 3 This is a schematic diagram illustrating the depth positioning principle based on the detector array layout of the first device example. Please refer to [link / reference]. Figure 3In the first device example, the planar geometric relationship included in the position conversion parameters may specifically include the base-height conversion relationship of the virtual triangle in the aforementioned angular plane (i.e., the XZ plane). The virtual triangle has a base parallel to the positioning reference direction (i.e., the first spatial direction X) and a vertex opposite to the base. The two base angles of the base are respectively associated with the angle values ​​of the first ray receiving angle θ1 and the second ray receiving angle θ2. The vertex is used to characterize the projection position of the target material 550 in the aforementioned angular plane (i.e., the XZ plane). Furthermore, the base-height conversion relationship is used to characterize the dimensional relationship between the side length of the base and the height of the vertex relative to the base.

[0102] If the coordinates of the endpoints of the base of the virtual triangle are det_1_i (first row coordinate position) and det_2_j (second row coordinate position), then the processor component 300 can be specifically configured as follows:

[0103] Based on the coordinates between the first row position det_1_i and the second row position det_2_j, determine the side length of the base of the virtual triangle;

[0104] Based on the side length of the base of the virtual triangle and the size relationship represented by the base-height transformation relationship of the virtual triangle, the height H of the vertex of the virtual triangle relative to the base is determined.

[0105] Based on the height H of the virtual triangle, the depth position Pz of the target material 550 in the spatial depth direction (e.g., the third spatial direction Z) of the detection space 400 is determined. Specifically, if the first array plane of the first detector array 210 and the second array plane of the second detector array 220 both coincide with the XY plane, and the depth position is referenced to the XY plane, then the position coordinates of the depth position Pz of the target material 550 in the spatial depth direction (e.g., the third spatial direction Z) of the detection space can be equal to the height H of the virtual triangle. However, it is understood that the reference for the depth position can also be set as any object feature, such as the outer contour surface of the object where the target material 550 is located, parallel to the first spatial direction X and / or the second spatial direction Y.

[0106] from Figure 3 As can be seen, the length of the base of the virtual triangle can be characterized by the position difference Δx between the first row coordinate position det_1_i and the second row coordinate position det_2_j. Therefore, in the first device instance, the processor component 300 can be specifically configured as follows:

[0107] The length of the base of the virtual triangle is determined based on the position difference Δx between the first row coordinate position det_1_i and the second row coordinate position det_2_j.

[0108] In the first device example, if the first ray receiving angle θ1 is the tilt angle of the first collimation direction relative to the positioning reference direction (i.e., the first spatial direction X), and the second ray receiving angle θ2 is the tilt angle of the second collimation direction relative to the positioning reference direction (i.e., the first spatial direction X), then the first angle information of the first ray receiving angle θ1 of the first detector array 210 includes the tangent function value tanθ1 of the first ray receiving angle θ1, and the second angle information of the second ray receiving angle θ2 of the second detector array 220 includes the tangent function value tanθ2 of the second ray receiving angle θ2. In this case, the height H of the vertex of the virtual triangle relative to the base can be expressed as the following expression (1):

[0109] H=Δx×tanθ1×tanθ2 / (tanθ1-tanθ2) Expression (1)

[0110] If the first ray receiving angle θ1 is 90°, that is, the first collimation direction is perpendicular to the positioning reference direction (i.e., the first spatial direction X) and parallel to the spatial depth direction (i.e., the third spatial direction Z), then the above expression (1) can be transformed into the following expression (2):

[0111] H=Δx×tanθ2 expression (2)

[0112] In the first device example, the processor component 300 can also be further used to determine the planar position of the target substance 550 in the XY plane, the planar position including a first planar position Px of the target substance 550 in the first spatial direction X, and a second planar position Py of the target substance 550 in the second spatial direction Y.

[0113] To determine the first plane position Px, the processor component 300 can be used to:

[0114] Based on the imaging position of the target material 550 in the row direction of the array plane of the detector array 200 (e.g., at the first row coordinate position det_1_i or the second row coordinate position det_2_j), the first planar position Px of the target material 550 in the first spatial direction X is determined. Furthermore, in the first device embodiment, the first planar position Px can also be associated with the depth position and the ray receiving angle (i.e., the first ray receiving angle θ1 or the second ray receiving angle θ2).

[0115] For example, if the first planar position Px of the target material 550 in the first spatial direction X is determined based on the first row coordinate position det_1_i of the target material 550 in the array plane of the first detector array 210, then the position coordinate value of the first planar position Px can be specifically expressed as the following expression (3):

[0116] Px = Wdet ×(i-0.5)+H / tanθ1 Expression (3)

[0117] In the above expression (3), W det The distance between the center points of every two detectors in the first detector array 210 in the row direction is given, and the position coordinates of the first planar position Px can be referenced to the origin of the spatial coordinate system.

[0118] If the first ray receiving angle θ1 is 90°, then the actual projection position of the target material 550 perpendicular to the array plane coincides with the center point of the first target detector. In this case, the above expression (3) can be transformed into the following expression (4):

[0119] Px = W det ×(i-0.5) Expression (4)

[0120] If at least one of the first detector array 210 and the second detector array 220 included in the detector array 200 is a linear array, then, in order to determine the second planar position Py, the processor component 300 can be used to:

[0121] Based on the unit offset step size Δy of the relative movement of the target material 550 and one of the linear arrays of the detector array 200 (e.g., the first detector array 210 or the second detector array 220) in the second spatial direction Y, and the cumulative number m of the line scan bar images included in the imaging data generated by the linear array before the target material 550 is detected, the second planar position Py of the target material 550 in the second spatial direction Y is determined. That is, the position coordinate value of the second planar position Py can be expressed as the following expression (5):

[0122] Py=Δy×m Expression (5)

[0123] The unit offset step size Δy can be determined by the relative movement speed and the imaging frequency of the detector array 200, and the movement speed and imaging frequency are configurable.

[0124] The process of determining the second plane position Py based on the unit offset step size Δy and the cumulative number of bars m can be considered as measuring the movement position of the target material 550 relative to the detection device along the second spatial direction Y using the unit offset step size Δy as the measurement step size. The starting position of this measurement process can be set with the origin of the spatial coordinate system as the reference. Furthermore, the cumulative number of bars m refers to the cumulative number of line scan bar images from the first moment when the object under inspection 500 reaches the starting position to the second moment when the target material 550 is detected.

[0125] Therefore, the processor component 300 can further generate three-dimensional spatial position information (Px, Py, Pz) including the first planar position Px, the second planar position Py, and the depth position Pz. This three-dimensional spatial position information (Px, Py, Pz) can be specifically represented by the following expression (6):

[0126] (W det ×(i-0.5)+H / tanθ1,Δy×m,H) Expression (6)

[0127] If the receiving angle θ1 of the first ray is 90°, then the above expression (6) can be transformed into the following expression (7):

[0128] (W det ×(i-0.5),Δy×m,H) Expression (7)

[0129] Alternatively, if the array mapping position described above is used to characterize the imaging position of the target material 550 in the positioning reference direction of the detector array 200, then the first row coordinate position det_1_i or the second row coordinate position det_2_j in the first device example can be replaced by the first row mapping position mapped by the image position coordinates to the first array plane (or the XY plane parallel to the first array plane) of the first detector array 210, and the second row mapping position mapped by the image position coordinates to the second array plane (or the XY plane parallel to the second array plane) of the second detector array 220. The first row mapping position can be obtained by converting the image position coordinates of the target material 550 in the first image direction (i.e., the image mapping direction of the first spatial direction X) of the first detection image and the second detection image, respectively.

[0130] Furthermore, the second planar position Py can also be determined based on the image position coordinates of the target material 550 in the second image direction (i.e., the image mapping direction of the second spatial direction Y) of the first detection image or the second detection image. For example, based on the coordinate transformation relationship described above, the image position coordinates can be converted into the second planar position Py mapped to the XY plane, which is parallel to both the first array plane of the first detector array 210 and the second array plane of the second detector array 220.

[0131] Figure 4 This is a schematic diagram of the detector array layout for a second device example of the detection apparatus in this application. Please refer to... Figure 4The second device example is similar to the first device embodiment in that it can be configured as a dual backscatter imaging device where both the first detector array 210 and the second detector array 220 employ backscatter imaging. Furthermore, the detection rays generated by the X-ray source 100 are collimated by the source-end collimating member and then pass through the gap between the first detector array 210 and the second detector array 220 in a fan-shaped pattern parallel to the XZ plane, heading towards the detection space. However, unlike the first device example, the first detector array 210 and the second detector array 220, which are staggered in the second spatial direction Y, are not arranged with their first and second array planes parallel and aligned with each other. Specifically, in the second device example, the second detector array 220 is tilted relative to the first detector array 220 about the first spatial direction X, such that the second array plane of the second detector array 220 is tilted relative to the first array plane of the first detector array 210 about the first spatial direction X, and the second array plane of the second detector array 220 is tilted about the first spatial direction X relative to the spatial depth direction (i.e., the third spatial direction Z). The aforementioned tilt and tilt angles are related to the second ray receiving angle θ2. For example, the aforementioned tilt angle can be equal to the second ray receiving angle θ2, and the aforementioned tilt angle can be complementary to the second ray receiving angle θ2.

[0132] Specifically, in the second device example, the first array plane of the first detector array 210 can be parallel to the XY plane and perpendicular to the spatial depth direction (i.e., the third spatial direction Z), while the second array plane of the second detector array 220 is inclined relative to both the XY plane and the spatial depth direction (i.e., the third spatial direction Z). Furthermore, the row directions of the first array plane of the first detector array 210 and the second array plane of the second detector array 220 are both parallel to the first spatial direction X.

[0133] In this configuration, the first detector array 210 is equipped with a first collimating member 610, and the second detector array 220 is equipped with a second collimating member 620. The first collimating channel of the first collimating member 610 is perpendicular to the first array plane of the first detector array 210, and the second collimating channel of the second collimating member 620 is perpendicular to the second array plane of the second detector array 220. Thus, the receiving angles of the first collimating channel and the second collimating channel are constrained by the planar angles of the first array plane and the second array plane, respectively. Accordingly, the aforementioned first ray beam includes scattered rays from the detection space reflected to the first detector array 210 through the first collimating channel constrained by the first ray receiving angle θ1, and the aforementioned second ray beam includes scattered rays from the detection space reflected to the second detector array 220 through the second collimating channel constrained by the second ray receiving angle θ2.

[0134] Therefore, in the second device example, the angular plane containing the angular difference between the first ray receiving angle θ1 of the first detector array 210 and the second ray receiving angle θ2 of the second detector array 220 is parallel to the YZ plane, and this angular plane intersects with both the first array plane of the first detector array 210 and the second array plane of the second detector array 220.

[0135] Therefore, in the second device example, the aforementioned positioning reference direction includes the column direction of the second detector array 220, which is parallel to the YZ plane and inclined relative to the spatial depth direction (e.g., the third spatial direction Z). Furthermore, the positioning reference direction in the second device example may not involve the row and column directions of the first detector array 210. Accordingly, the second detector array 220 is a planar array comprising at least two rows of detectors arranged along the column direction. The row direction of this planar array is parallel to the first spatial direction X, and the column direction is parallel to the YZ plane and the aforementioned corner plane, parallel to the intersection of the corner plane and the second array plane, and inclined relative to both the second spatial direction Y and the spatial depth direction (i.e., the third spatial direction Z). The first detector array 210 is preferably a linear array comprising a single row of detectors, with the row direction of the linear array parallel to the first spatial direction X. In this case, the first imaging data generated by the first detector array 210 includes frame images that are line scan bar graphs, and the second imaging data generated by the second detector array 220 includes frame images that are two-dimensional graphs.

[0136] Figure 5 This is a schematic diagram illustrating the depth positioning principle based on the detector array layout of the second device example. Please refer to [link / reference]. Figure 5 In the second device example, since the second array plane of the second detector array 220 is tilted relative to the spatial depth direction (i.e., the third spatial direction Z), different position intervals in the spatial depth direction (e.g., the third spatial direction Z) can be mapped to different rows in the second array plane of the second detector array 220 along the column direction (i.e., the positioning reference direction) along the second ray receiving angle θ2. Therefore, the position transformation parameter in the second device example can include: the position mapping relationship between any coordinate position in the positioning reference direction and the calibration position in the spatial depth direction (e.g., the third spatial direction Z). That is, the position mapping relationship can be considered as mapping the position interval in the spatial depth direction (e.g., the third spatial direction Z) to each coordinate position in the positioning reference direction after being divided, and this position mapping relationship is associated with the second ray receiving angle θ2.

[0137] Accordingly, in the second device example, the array coordinate position of the target detector imaging the target substance 550 in the detector array 200 in the positioning reference direction includes: the column coordinate position det_2_p of the second target detector imaging the target substance 550 in the second detector array 220 (the subscript p indicates the sorting position of the second target detector in the column direction of the second detector array 220), and the processor component 300 can be specifically configured as follows:

[0138] Based on the aforementioned position mapping relationship, the calibration position H_ref_p corresponding to the column coordinate position det_2_p in the spatial depth direction (e.g., the third spatial direction Z) is determined as the depth position Pz of the target material 550 in the spatial depth direction (e.g., the third spatial direction Z) of the detection space 400.

[0139] Similar to the first device example, in the second device example, the processor component 300 can also be further used to determine the first planar position Px and the second planar position Py of the target material 550 in the XY plane, and generate three-dimensional spatial position information (Px, Py, Pz) including the first planar position Px, the second planar position Py and the depth position Pz.

[0140] Preferably, in the second device example, the first ray receiving angle θ1 and the second ray receiving angle θ2 can both be 90° perpendicular to the first spatial direction X in the XZ plane. If so, the method for determining the position Px of the first plane can refer to the expression (4) described in the first device example.

[0141] Furthermore, the second planar position Py can be determined by referring to the expression (5) described in the first device example, using the unit offset step Δy of the relative movement of the target material 550 and the first detector array 220 selected as a linear array in the second spatial direction Y, and the first imaging data (i.e., the line scan bar graph) generated by the first detector array 220.

[0142] That is, the first imaging data generated by the first detector array 210 can be used to determine two position information (i.e., the first plane position Px and the second plane position Py) in the three-dimensional spatial position information (Px, Py, Pz). Therefore, the first detector array 210 can be regarded as the main detector array for three-dimensional spatial positioning, and the second detector array 220 can be regarded as the auxiliary detector array for three-dimensional spatial positioning.

[0143] Also, please review Figure 4 In the second device example:

[0144] The first detector array 210 is used for positioning a first planar position Px. The positioning accuracy of the first planar position Px is determined by the first row specification size X1 of a single detector in the first detector array 210 in the row direction. In order to reduce the impact of statistical fluctuations of the second detection image on positioning, the second row specification size X2 of a single detector in the second detector array 220 in the row direction can be larger than the first row specification size X1.

[0145] The second detector array 220 is used for the localization of depth position Pz. The localization accuracy of depth position Pz, that is, the segmentation accuracy of the position mapping relationship on the position interval in the spatial depth direction (e.g., the third spatial direction Z), is determined by the second column specification size Y2 of a single detector in the second detector array 210 in the column direction. In order to reduce the impact of statistical fluctuations of the first detection image on the image quality of the first detection image, the first column specification size Y1 of a single detector in the first detector array 210 in the column direction can be larger than the second column specification size Y2.

[0146] It is understood that the first detector array 210 and the second detector array 220 in the second device implementation can also be interchanged. That is, the first detector array 210 can be a planar array, and the column direction of the first detector array 210 is a positioning reference direction that is tilted relative to the spatial depth direction (e.g., the third spatial direction Z). Furthermore, each column of the first detector array 210 separates the position intervals in the spatial depth direction (e.g., the third spatial direction Z). In this case, the above-mentioned position mapping relationship is associated with the first ray receiving angle θ1.

[0147] That is, in the second device example, the positioning reference direction may include one of the row and column directions of the first detector array 210 or the second detector array 220 that is tilted relative to the spatial depth direction (e.g., the third spatial direction Z), the position mapping relationship may be associated with the first ray receiving angle θ1 or the second ray receiving angle θ2, and the processor component 300 may be used for:

[0148] Based on the aforementioned position mapping relationship, the calibration position corresponding to the array coordinate position of the target detector imaging the target material 550 in the first detector array 210 or the second detector array 220 in the positioning reference direction is determined as the depth position Pz of the target material 550 in the spatial depth direction (e.g., the third spatial direction Z) of the detection space 400.

[0149] Figure 6 This is a schematic diagram illustrating the detector array layout and depth positioning principle of a third device example of the detection apparatus in this application. Please refer to... Figure 6In the third device example, the first array plane of the first detector array 210 and the second array plane of the second detector array 220 are still parallel to each other as in the first device example, and the row directions of the first array plane of the first detector array 210 and the second array plane of the second detector array 220 are both parallel to the first spatial direction X. However, unlike the first device embodiment, the second detector array 220 of the third device example can be configured to perform transmission imaging on the detection space 400 on the opposite side of the X-ray source 100. That is, the third device example is configured as a dual-mode device in which the first detector array 210 adopts backscatter imaging and the second detector array 220 adopts transmission imaging.

[0150] Specifically, the first detector array 210 and the second detector array 220 are arranged at intervals in the spatial depth direction (i.e., the third spatial direction Z). The first detector array 210 and the second detector array 220 are opposite to each other across the detection space 400, so that the second detector array 220 can perform transmission imaging of the detection space 400 on the opposite side of the X-ray source 100.

[0151] In this case, the first detector array 210 is equipped with a first collimation member 610, and the first collimation channel of the first collimation member 610 receives a first ray at a first ray receiving angle θ1. Figure 6 (Taking a first ray receiving angle θ1 of 90° as an example for illustration) Relative to the first array plane of the first detector array 210, and the aforementioned first ray beam includes scattered rays from the detection space reflected to the first detector array 210 through a first collimation channel constrained at the first ray receiving angle θ1; the second ray receiving angle θ2 of the second detector array 220 is related to the emission angle of the detection ray generated by the ray source 100. Specifically, the detection ray generated by the ray source 100, after being collimated by the source-end collimating member, forms a fan shape parallel to the XZ plane, and penetrates the detection space 400 from the first detector array 210 on one side of the second spatial direction Y, heading towards the second detector array 220. Therefore, for each detector in the second detector array 220, the fan angle of the ray beam received by each detector in the fan shape is the second ray receiving angle θ2, that is, the second ray receiving angle θ2 can be expressed as {θ 2,j}, θ 2,j The second ray receiving angle θ2 represents the angle value corresponding to the j-th detector in the row direction of the second detector array 220.

[0152] Therefore, in the third device example, the angular plane containing the angular difference between the ray receiving angles of the first detector array 210 and the second detector array 220 is the XZ plane, and the intersection line of this angular plane with the first array plane of the first detector array 210 and the second array plane of the second detector array 220 is parallel to the first spatial direction X.

[0153] Therefore, similar to the first device example, the positioning reference direction in the third device example may include the row direction of the first detector array 210 parallel to the first spatial direction X, and the row direction of the second detector array 220 parallel to the first spatial direction X. Furthermore, preferably, both the first detector array 210 and the second detector array 220 in the third device example can be linear arrays comprising only a single row of detectors parallel to the first spatial direction X.

[0154] Furthermore, similar to the first device instance, the position transformation parameters in the third device instance also include the planar geometric relationships described above, just as in the first device instance. Unlike the first device instance, the second ray receiving angle {θ} in the third device instance... 2,j The second detector array 220 contains multiple detectors corresponding to different angle values ​​in the positioning reference direction (i.e., the row direction), rather than a single angle value as in the first device example.

[0155] That is, in the third device example, the virtual triangle represented by the planar geometric relationship described above and the second ray receiving angle {θ} 2,j One of the base angles of the virtual triangle can have multiple selectable angle values, and when determining the length of the base of the virtual triangle, the virtual triangle is related to the angle {θ} of the second ray receiving angle. 2,j The angle value of one side of the bottom corner is associated with the second row coordinate position det_2_j of the second target detector in the second detector array 220 that images the target material 550 in the second array plane in the positioning reference direction (i.e. the first spatial direction X).

[0156] It is evident that the third device instance and the first device instance share the following commonalities:

[0157] The array coordinate positions of the target detectors imaging the target material 550 in the detector array 200 in the positioning reference direction include the first row coordinate position det_1_i of the first target detector imaging the target material 550 in the first detector array 210 and the second row coordinate position det_2_j of the second target detector imaging the target material 550 in the second detector array 220. Furthermore, the processor component 300 can determine the depth position Pz of the target material 550 in the spatial depth direction (e.g., the third spatial direction Z) of the detection space 400 based on the first row coordinate position det_1_i and the second row coordinate position det_2_j.

[0158] If the geometric relationship includes the base-height transformation relationship of the virtual triangle described in the first device instance, then the commonality between the third device instance and the first device instance can also be specifically manifested in the following processing method of the processor component 300:

[0159] For example, processor component 300 can determine the length of the base of the virtual triangle based on the first row coordinate position det_1_i and the second row coordinate position det_2_j;

[0160] Based on the side length of the base of the virtual triangle and the size relationship represented by the base-height transformation relationship of the virtual triangle, the height H of the vertex of the virtual triangle relative to the base is determined.

[0161] Based on the height H of the virtual triangle, the depth position Pz of the target material 550 in the spatial depth direction (e.g., the third spatial direction Z) of the detection space 400 is determined.

[0162] Furthermore, the difference between the third device instance and the first device instance can be specifically manifested in the following method by which the processor component 300 determines the length of the base of the virtual triangle:

[0163] Based on the second row coordinate position det_2_j, determine the angle {θ} between the virtual triangle and the second ray receiving angle. 2,j The target angle value of one side of the bottom corner is associated with the target angle value, and this target angle value is related to the second ray receiving angle {θ}. 2,j The angle value θ corresponding to the second target detector located at the second coordinate position det_2_j in the second row. 2,j Correlation, for example, the target angle value can be related to the second ray receiving angle {θ}. 2,j The angle value θ corresponding to the second target detector located at the second coordinate position det_2_j in the second row. 2,j Equal or complementary;

[0164] Based on the position offset x0 of the first row coordinate position det_1_i compared to the reference row coordinate position, determine the position of the virtual triangle relative to the second ray receiving angle {θ}. 2,j The side length of the bottom edge when the bottom angle of the associated side is the target angle value mentioned above.

[0165] In other words, the third device instance differs from the first device instance in that:

[0166] When determining the height H of the virtual triangle using the expression (1) or expression (2) described in the first device example, the Δx characterizing the length of the base side in the expression (1) or expression (2) can be the position offset x0 of the first row coordinate position det_1_i in the first array plane. The position offset x0 refers to the position offset of the i-th detector (i.e. the first target detector) imaging the target material 550 in the first detector array 210 compared to the reference row coordinate position in the first array plane of the first detector array 210. The reference row coordinate position can be the projection position of the ray source 100 along the spatial depth direction (i.e. the third spatial direction Z) in the first array plane (e.g., the row coordinate position of the first detector arranged at the first position in the row direction in the first array plane of the first detector array 210). In addition, in the spatial depth direction (i.e. the third spatial direction Z), the position of the ray source 100 coincides with the planar position of the XY plane, that is, the ray source 100 is located in the XY plane.

[0167] The second ray receiving angle θ2 in expression (1) or expression (2) can be specifically the ray receiving angle θ corresponding to the j-th detector (i.e., the second target detector) in the second detector array 220 that images the target material 550. 2,j .

[0168] That is, expression (1) in the first device instance can be transformed into expression (8) in the third device instance:

[0169] H = x0 × tanθ1 × tanθ 2,j / (tanθ1-tanθ 2,j Expression (8)

[0170] Similarly, expression (2) in the first device instance can be transformed into expression (9) in the third device instance:

[0171] H = x0 × tanθ 2,j Expression (9)

[0172] Similar to the first device example, in the third device example, the processor component 300 can also be further used to determine the first planar position Px and the second planar position Py of the target material 550 in the XY plane, and generate three-dimensional spatial position information (Px, Py, Pz) including the first planar position Px, the second planar position Py and the depth position Pz.

[0173] The method for determining the first plane position Px can refer to the following expression (10), and this expression (10) can be regarded as an evolution of the expression (3) described in the first device example:

[0174] Px=x0+H / tanθ1 Expression (10)

[0175] If the first ray receiving angle θ1 is 90°, then the actual projection position of the target material 550 perpendicular to the array plane coincides with the center point of the i-th detector (i.e. the first target detector). At this time, the above expression (10) can be equivalent to determining the first plane position Px as the position offset x0 of the first row coordinate position det_1_i in the first array plane.

[0176] As for the second plane position Py, the processor component 300 in the third device instance can be determined by referring to the expression (5) described in the first device instance.

[0177] In addition, the first row coordinate position det_1_i and the second row coordinate position det_2_j in the third device instance can also be replaced with the array mapping position described above, as described in the first device instance section. Furthermore, the second plane position Py can also be determined based on the image position coordinates, as described in the first device instance section, which will not be elaborated here.

[0178] Figure 7 This is an exemplary flowchart illustrating a target localization method according to an embodiment of this application. Please refer to... Figure 7 In embodiments of this application, the target localization method may include:

[0179] S710: Based on the image position information of the target substance appearing in the detection space in the detection image, determine the imaging position of the target substance in the positioning reference direction of the detector array.

[0180] The detection image is generated based on the imaging data generated by the detector array imaging the detection space. The detector array includes a first detector array and a second detector array. The first detector array is used to perform backscatter imaging of the detection space using detection rays received from the detection space at a first ray receiving angle. The second detector array is used to perform backscatter imaging or transmission imaging of the detection space using detection rays received from the detection space at a second ray receiving angle. There is an angular difference between the first ray receiving angle and the second ray receiving angle. The angular plane where the angular difference is located intersects with the array plane of the detector array. Furthermore, the positioning reference direction is parallel to the line of intersection between the angular plane and the array plane of the detector array.

[0181] For example, S710 may specifically include: determining the array coordinate position of the target detector in the detector array that images the target material in the detection image based on the image position information of the target material in the detection image, the array coordinate position being used to characterize the imaging position of the target material in the positioning reference direction of the detector array, and the positioning reference direction may include one of the directions of the row and column directions of the detector array that are parallel to the corner plane.

[0182] S720: Based on the imaging position of the target material in the positioning reference direction in the array plane of the detector array and the preset position transformation parameters, determine the depth position of the target material in the spatial depth direction of the detection space.

[0183] The spatial depth direction intersects the array plane of the detector array, and is parallel to the angular plane where there is an angular difference between the ray receiving angles of the first detector array and the second detector array for the ray beam. Furthermore, a pre-set position conversion parameter is associated with this angular difference, or in other words, the position conversion parameter is associated with at least one of the ray receiving angles of the first and second rays.

[0184] For example, S720 may specifically include: determining the depth position of the target material in the spatial depth direction of the detection space based on the array coordinate position of the target detector imaging the target material in the positioning reference direction and the aforementioned position transformation parameters.

[0185] Based on the above embodiments, by configuring the detector array used for imaging the detection space to include a first detector array based on backscatter imaging and a second detector array with a different ray receiving angle than the first detector array, and by making the angular plane containing the angular difference between the ray receiving angles of the first detector array and the second detector array intersect with the array plane of the detector array, the depth position of the target material in the spatial depth direction intersecting the array plane can be determined based on the imaging position of the target material appearing in the detection space in a positioning reference direction parallel to the intersection of the angular plane and the array plane, and the position transformation parameter associated with the angular difference. This helps to improve the positioning efficiency of target positioning based on backscatter imaging.

[0186] In the embodiments of this application, the specific processing procedure of S720 may vary depending on the layout of the first detector array and the second detector array.

[0187] For the detector array layout in the first or third device example described above, the position transformation parameters include: a planar geometric relationship between an arbitrary coordinate position in the positioning reference direction and the projected position of the target material's spatial position in the angular plane (i.e., the XZ plane) where the angular difference between the ray receiving angles of the first and second detector arrays lies; and this planar geometric relationship is associated with the first ray receiving angle θ1 of the first detector array and the second ray receiving angle θ2 of the second detector array. In this case, S720 may specifically include:

[0188] Based on the array coordinates of the target detectors in the first and second detector arrays that image the target material in the positioning reference direction, and the aforementioned planar geometric relationship, the depth position of the target material in the spatial depth direction of the detection space is determined.

[0189] As described above, in the first or third device example, the first array plane of the first detector array and the second array plane of the second detector array are parallel to each other, the spatial depth direction is perpendicular to the first and second array planes, and the row directions of both the first and second array planes are parallel to the first spatial direction X. The relative positions of the target material, the radiation source, and the detector array in the first spatial direction X are fixed, and the target material, the radiation source, and the detector array move relative to each other in the second spatial direction Y, which is perpendicular to the first spatial direction X. The positioning reference direction includes the row direction of the first array plane of the first detector array and the row direction of the second array plane of the second detector array. Furthermore, the array coordinate position of the target detector in the detector array that images the target material in the positioning reference direction includes at least the first row coordinate position of the first target detector in the first detector array that images the target material and the second row coordinate position of the second target detector in the second detector array that images the target material. In this case, S720 may specifically include:

[0190] Based on the coordinate positions of the first and second rows, as well as the aforementioned planar geometric relationships, the depth position of the target material in the spatial depth direction of the detection space is determined.

[0191] As described above, the planar geometric relationship can include the aforementioned base-height transformation relationship of the virtual triangle. In this case, the process by which S720 determines the depth position using the first row coordinate position, the second row coordinate position, and the aforementioned planar geometric relationship can specifically include:

[0192] Based on the coordinate positions of the first and second rows, determine the side length of the base of the virtual triangle described above;

[0193] Based on the side length of the base of the virtual triangle and the dimensional relationship between the side length of the base of the virtual triangle and the height of the vertex representing the projection position of the target material relative to the base, the height of the vertex of the virtual triangle relative to the base is determined.

[0194] The depth position of the target material in the spatial depth direction of the detection space is determined based on the height of the vertex of the virtual triangle relative to the base.

[0195] If, as described in the first device example above, the first detector array and the second detector array are staggered in the second spatial direction Y, the first array plane of the first detector array and the second array plane of the second detector array are aligned in the same direction, and the second detector array is specifically used to perform backscatter imaging of the detection space on the same side of the X-ray source, then the process of determining the side length of the base of the virtual triangle in S720 may include:

[0196] The length of the base of the virtual triangle is determined based on the positional difference between the first and second row coordinate positions.

[0197] If, as described in the third device example above, the first detector array and the second detector array are arranged at intervals in the third spatial direction Z, with the first array plane of the first detector array and the second array plane of the second detector array facing each other across the detection space, and the second detector array is specifically used to perform transmission imaging of the detection space on the opposite side of the X-ray source, and the second angle information of the second detector array includes different angle values ​​corresponding to the second X-ray receiving angle at multiple detectors in the row direction of the second detector array, then the process of determining the side length of the base of the virtual triangle in S720 may include:

[0198] Based on the second row coordinate position, determine the target angle value of one bottom corner of the virtual triangle that is associated with the second ray receiving angle. This target angle value is associated with the angle value corresponding to the second ray receiving angle at the second target detector.

[0199] Based on the position offset of the first row coordinate position in the first array plane of the first detector array compared to the reference row coordinate position, the length of the base of the virtual triangle is determined when the base angle of the virtual triangle associated with the second ray receiving angle is the target angle value. The reference row coordinate position is the projection position of the ray source along the spatial depth direction in the first array plane of the first detector array.

[0200] For the detector array layout in the second device example described above, the position transformation parameters include the position mapping relationship between any coordinate position in the positioning reference direction and the calibration position in the spatial depth direction. The positioning reference direction is tilted relative to the spatial depth direction (i.e., the third spatial direction Z), and this position mapping relationship is associated with the first ray receiving angle θ1 of the first detector array or the second ray receiving angle θ2 of the second detector array. In this case, S720 may specifically include:

[0201] Based on the array coordinates of the target detector in the detector array that images the target material in the positioning reference direction, and the aforementioned position mapping relationship, the depth position of the target material in the spatial depth direction of the detection space is determined.

[0202] For example, based on the aforementioned position mapping relationship, S720 can determine the calibration position corresponding to the array coordinate position of the target detector imaging the target material in the first detector array or the second detector array in the positioning reference direction as the depth position of the target material in the spatial depth direction (e.g., the third spatial direction Z) of the detection space.

[0203] Specifically, as described in the second device example above, the first detector array and the second detector array are staggered in the second spatial direction Y. The first array plane of the first detector array is parallel to the XY plane, and the spatial depth direction is perpendicular to the first array plane of the first detector array. The second array plane of the second detector array is tilted about the first spatial direction X relative to the first array plane of the first detector array, and the second array plane of the second detector array is tilted about the first spatial direction X relative to the spatial depth direction (i.e., the third spatial direction Z). The aforementioned tilt and tilt angles are related to the second ray receiving angle θ2. For example, the aforementioned tilt angle can be equal to the second ray receiving angle θ2, and the aforementioned tilt angle can be complementary to the second ray receiving angle θ2. The second detector array is a planar array containing at least two rows of detectors. The row direction of the second detector array is parallel to the first spatial direction X, the positioning reference direction is the column direction of the second detector array, and the array coordinate position of the target detector imaging the target material in the detector array in the positioning reference direction includes the column coordinate position of the second target detector imaging the target material in the second detector array. In this case, S720 may specifically include:

[0204] Based on the above position mapping relationship, the calibration position corresponding to the column coordinate position of the second target detector in the spatial depth direction is determined as the depth position of the target material in the spatial depth direction of the detection space.

[0205] In addition, as described above regarding the detection device, in the embodiments of this application, such as Figure 7The target localization method shown may further include:

[0206] Based on the imaging position of the target material in the positioning reference direction of the detector array, the first plane position of the target material in the first spatial direction X is determined.

[0207] And / or,

[0208] The unit offset step Δy of the relative movement of the target array and the linear array of the detector array (e.g., the first detector array or the second detector array) in the second spatial direction, and the cumulative number m of the line scan bar images generated by the imaging data of the linear array of the detector array 200 (e.g., the first detector array or the second detector array) before the target material is detected, determine the second plane position of the target material in the second spatial Y direction.

[0209] In addition, as described above regarding the detection device, as an alternative to the array coordinate position, S710 can also determine the array mapping position for characterizing the imaging position based on the image position information, and the determination of the first plane position and the second plane position can also use the array mapping position.

[0210] Figure 8 This is an exemplary flowchart of a target positioning device according to an embodiment of this application. Please refer to... Figure 8 In the embodiments of this application, the target positioning device may include an imaging position determination module 810 and a depth position positioning module 820.

[0211] The imaging position determination module 810 is used to determine the imaging position of the target substance in the positioning reference direction of the detector array based on the image position information of the target substance appearing in the detection space in the detection image.

[0212] The detection image is generated based on the imaging data generated by the detector array imaging the detection space. The detector array includes a first detector array and a second detector array. The first detector array is used to perform backscatter imaging of the detection space using detection rays received from the detection space at a first ray receiving angle. The second detector array is used to perform backscatter imaging or transmission imaging of the detection space using detection rays received from the detection space at a second ray receiving angle. There is an angular difference between the first ray receiving angle and the second ray receiving angle. The angular plane where the angular difference is located intersects with the array plane of the detector array. Furthermore, the positioning reference direction is parallel to the line of intersection between the angular plane and the array plane of the detector array.

[0213] The depth positioning module 820 is used to determine the depth position of the target material in the spatial depth direction of the detection space based on the imaging position of the target material in the positioning reference direction in the array plane of the detector array and the preset position transformation parameters.

[0214] The spatial depth direction intersects the array plane of the detector array, and is parallel to the angular plane where there is an angular difference between the ray receiving angles of the first detector array and the second detector array for the ray beam. Furthermore, a pre-set position conversion parameter is associated with this angular difference, or in other words, the position conversion parameter is associated with at least one of the ray receiving angles of the first and second rays.

[0215] Based on the above embodiments, by configuring the detector array used for imaging the detection space to include a first detector array based on backscatter imaging and a second detector array with a different ray receiving angle than the first detector array, and by making the angular plane containing the angular difference between the ray receiving angles of the first detector array and the second detector array intersect with the array plane of the detector array, the depth position of the target material in the spatial depth direction intersecting the array plane can be determined based on the imaging position of the target material appearing in the detection space in a positioning reference direction parallel to the intersection of the angular plane and the array plane, and the position transformation parameter associated with the angular difference. This helps to improve the positioning efficiency of target positioning based on backscatter imaging.

[0216] In the embodiments of this application, the imaging position determination module 810 can be referred to in the description of S710 in the target positioning method above, and the specific processing method of the depth position positioning module 820 can be referred to in the description of S720 in the target positioning method above, and will not be repeated here.

[0217] In addition, in the embodiments of this application, as shown Figure 8 The target positioning device shown may further include components not in Figure 8 The planar position positioning module shown is used to determine the first planar position of the target substance in the first spatial direction X, and / or the second planar position of the target substance in the second spatial direction Y. The method for determining the first and second planar positions can be referred to the previous description, and will not be repeated here.

[0218] Another embodiment of this application provides a non-transitory computer-readable storage medium that stores instructions that, when executed by a processor, cause the processor to perform the steps of the target localization method as described above.

[0219] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A detection device based on backscatter imaging, characterized in that, include: A radiation source, used to generate detection radiation into the detection space; A detector array includes a first detector array and a second detector array for backscattering imaging of the detection space using detection rays received from the detection space; wherein the first detector array is a linear array including a single row of detectors and receives the detection rays from the detection space at a first ray receiving angle; the second detector array is a planar array including at least two rows of detectors and receives the detection rays from the detection space at a second ray receiving angle; the imaging data generated by the first and second detector arrays imaging the detection space is used to generate a detection image; the row directions of the first and second detector arrays are both parallel to a first spatial direction; the first and second detector arrays are staggered in a second spatial direction perpendicular to the first spatial direction; the column direction of the second detector array is tilted relative to the array plane of the first detector array at an angle of less than 90°; there is an angular difference between the first and second ray receiving angles; the angular plane where the angular difference occurs is parallel to the second spatial direction and the spatial depth direction of the detection space; the spatial depth direction is perpendicular to the first and second spatial directions. A processor component is configured to identify a target substance inside an object under inspection in the detection image, the target substance moving relative to the detection device in a second spatial direction, and the processor component is further configured to: determine the array coordinate position of a target detector in the detector array that images the target substance in the detection image in a positioning reference direction based on the image position information of the target substance in the detection image; wherein the array coordinate position includes the column coordinate position of the target detector in the column direction of the second detector array; Based on the column coordinate position of the target detector and the preset position transformation parameters, the depth position of the target material in the spatial depth direction is determined; wherein, the position transformation parameters are used to characterize the mapping of the position interval in the spatial depth direction to each coordinate position in the column direction of the second detector array after being divided.

2. The detection device according to claim 1, characterized in that, The position transformation parameters include: the position mapping relationship between any coordinate position in the column direction of the second detector array and the calibration position in the spatial depth direction.

3. The detection device according to claim 2, characterized in that, The position mapping relationship is associated with the second ray receiving angle.

4. The detection device according to claim 2, characterized in that, The processor component is specifically configured as follows: Based on the position mapping relationship, the calibration position corresponding to the column coordinate position of the target detector in the spatial depth direction is determined as the depth position.

5. The detection device according to claim 1, characterized in that, The tilt angle of the column direction of the second detector array relative to the spatial depth direction is related to the second ray receiving angle.

6. The detection device according to claim 1, characterized in that, The relative positions of the target substance and the detection device in the first spatial direction are fixed.

7. The detection device according to claim 1, characterized in that, The array coordinate position further includes the row coordinate position of the target detector in the row direction of the first detector array or the second detector array, and the processor component is further configured to: Based on the row coordinate position of the target detector, the first planar position of the target substance in the first spatial direction is determined.

8. The detection device according to claim 1, characterized in that, The processor component is further used for: The second planar position of the target material in the second spatial direction is determined based on the unit offset step size of the relative movement between the target material and the detector array in the second spatial direction, and the cumulative number of line scan bar images included in the imaging data before the target material is detected.

9. A target localization method, characterized in that, include: Based on the image position information of the target material inside the object under test appearing in the detection space in the detection image, the array coordinate position of the target detector in the detector array that images the target material is determined in the positioning reference direction; wherein, the detection image is generated based on the imaging data generated by the detector array imaging the detection space, and the detector array includes a first detector array and a second detector array for backscattering imaging of the detection space using detection rays generated by a radiation source received from the detection space, the first detector array being a linear array including a single row of detectors and receiving the detection rays from the detection space at a first ray receiving angle, and the second detector array being a planar array including at least two rows of detectors and receiving the detection rays from the detection space at a second ray receiving angle. The detection rays are received in a manner where the row directions of the first detector array and the second detector array are parallel to the first spatial direction, the first detector array and the second detector array are staggered in a second spatial direction perpendicular to the first spatial direction, the column direction of the second detector array is tilted relative to the array plane of the first detector array at an angle of less than 90°, there is an angular difference between the first ray receiving angle and the second ray receiving angle, the angular plane where the angular difference is located is parallel to the second spatial direction and the spatial depth direction of the detection space, the spatial depth direction is perpendicular to the first spatial direction and the second spatial direction, and the array coordinate position includes the column coordinate position of the target detector in the column direction of the second detector array; Based on the column coordinate position of the target detector and the preset position transformation parameters, the depth position of the target material in the spatial depth direction is determined; wherein, the position transformation parameters are used to characterize the mapping of the position interval in the spatial depth direction to each coordinate position in the column direction of the second detector array after being divided.

10. The target localization method according to claim 9, characterized in that, The position conversion parameters include: a position mapping relationship between any coordinate position in the column direction of the second detector array and a calibration position in the spatial depth direction, the position mapping relationship being associated with the second ray receiving angle; and determining the depth position of the target material in the spatial depth direction based on the column coordinate position of the target detector and the position conversion parameters includes: determining the calibration position corresponding to the array coordinate position of the target detector in the spatial depth direction as the depth position based on the position mapping relationship.

11. A target positioning device, characterized in that, include: An imaging position determination module is used to determine the array coordinate position of the target detector in the detector array imaging the target material in the positioning reference direction based on the image position information of the target material inside the object under test appearing in the detection space in the detection image; wherein, the detection image is generated based on the imaging data generated by the detector array imaging the detection space, and the detector array includes a first detector array and a second detector array for backscattering imaging of the detection space using detection rays generated by a radiation source received from the detection space, the first detector array being a linear array including a single row of detectors and receiving the detection rays from the detection space at a first radiation receiving angle, and the second detector array being a planar array including at least two rows of detectors and receiving the detection rays from the detection space at a second radiation receiving angle. The detection space receives the detection rays, and there is an angular difference between the first ray receiving angle and the second ray receiving angle. The row directions of the first detector array and the second detector array are both parallel to the first spatial direction. The first detector array and the second detector array are staggered in a second spatial direction perpendicular to the first spatial direction. The column direction of the second detector array is tilted relative to the array plane of the first detector array at an angle of less than 90°. The angular plane where the angular difference occurs is parallel to the second spatial direction and the spatial depth direction of the detection space. The spatial depth direction is perpendicular to the first spatial direction and the second spatial direction. Furthermore, the array coordinate position includes the column coordinate position of the target detector in the column direction of the second detector array. The depth positioning module is used to determine the depth position of the target material in the spatial depth direction based on the column coordinate position of the target detector and the preset position transformation parameters, wherein the position transformation parameters are used to characterize the mapping of the position interval in the spatial depth direction to each coordinate position in the column direction of the second detector array after being divided.

12. A non-transitory computer-readable storage medium, characterized in that, The non-transitory computer-readable storage medium stores instructions, which, when executed by a processor, cause the processor to perform the target localization method as described in claim 9 or 10.

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