Linear CT (Computed Tomography) imaging system with multi-space-direction imaging capability and scanning imaging method

Abstract

The invention provides a linear CT imaging system with multi-space-direction imaging capability and a scanning imaging method, and relates to the technical field of image processing and radiation imaging. The system comprises a conveying device used for enabling a scanning object to move along a preset linear scanning track; each imaging unit comprises at least one radiation source and at least one detector, and the plurality of imaging units comprise a first imaging unit and a second imaging unit; a ray beam emitted by the ray source of the first imaging unit forms a first scanning main sector, a ray beam emitted by the ray source of the second imaging unit forms a second scanning main sector, and the first scanning main sector and the second scanning main sector are located in different planes.

Description

Technical Field

[0001] This application relates to the fields of radiation imaging and nondestructive testing technology, and more specifically, to a linear CT imaging system and scanning imaging method with multi-spatial direction imaging capability. Background Technology

[0002] In a linear CT imaging system, the object being scanned, or the X-ray source and detector, moves relative to each other along a predetermined straight line to acquire projection data at different positions, thus achieving tomographic imaging. Compared to closed-track scanning methods, linear CT imaging systems do not rely on rotation around the object, resulting in a more compact overall structure, simpler movement, and greater suitability for the inspection of continuously transported workpieces.

[0003] However, existing linear CT imaging systems still have shortcomings. Single-segment linear CT imaging systems, because they scan only along a single straight line, have a limited range of projection direction variation, resulting in incomplete angular space sampling and a tendency to produce finite angle artifacts. To alleviate this problem, some solutions have proposed multi-segment linear CT scanning imaging schemes, which jointly acquire projection data through multiple linear scanning segments in different directions to expand the angular coverage. However, most existing multi-segment linear CT imaging systems are still limited to the same imaging plane, essentially constituting coplanar multi-segment scanning, which can only improve the problem of insufficient in-plane sampling, but lacks sampling capability for out-of-plane directions.

[0004] It should be noted that the information disclosed in this section is only used to understand the background of the inventive concept of this application. Therefore, the above information may include information that does not constitute prior art. Summary of the Invention

[0005] In view of at least one of the above-mentioned technical problems, embodiments of this application provide a linear CT imaging system and scanning imaging method with multi-spatial direction imaging capability.

[0006] According to a first aspect of this application, a linear CT imaging system with multi-spatial-direction imaging capability is provided. The system includes: a transport device for moving a scanned object along a predetermined linear scanning trajectory; and a plurality of imaging units, each imaging unit including at least one X-ray source and at least one detector, the X-ray source for emitting a X-ray beam, and the detector for detecting the X-ray beam emitted by the X-ray source and passing through the scanned object. The plurality of imaging units includes a first imaging unit and a second imaging unit. The X-ray source of the first imaging unit is located at a first spatial orientation relative to the linear scanning trajectory to scan the scanned object from the first spatial direction. The X-ray source of the second imaging unit is located at a second spatial orientation relative to the linear scanning trajectory to scan the scanned object from the second spatial direction. The first spatial direction is different from the second spatial direction. The X-ray beam emitted by the X-ray source of the first imaging unit forms a first main scanning sector, and the X-ray beam emitted by the X-ray source of the second imaging unit forms a second main scanning sector. The first main scanning sector and the second main scanning sector are located in different planes.

[0007] According to some embodiments of this application, the plane containing the first scanning main sector intersects with the plane containing the second scanning main sector.

[0008] According to some embodiments of this application, the angle between the plane where the first scanning main sector is located and the plane where the second scanning main sector is located is greater than 0° and less than 90°.

[0009] According to some embodiments of this application, the plurality of imaging units includes at least two imaging units that are independently configured with each other.

[0010] According to some embodiments of this application, at least some of the plurality of imaging units are formed by the same imaging unit undergoing spatial orientation transformation during the scanning process.

[0011] According to some embodiments of this application, the first imaging unit includes a first radiation source, the second imaging unit includes a second radiation source, the first radiation source and the second radiation source are independently arranged, and the first radiation source and the second radiation source are distributed at intervals along a predetermined spatial trajectory.

[0012] According to some embodiments of this application, the X-ray source of the first imaging unit and the X-ray source of the second imaging unit are formed by the same X-ray source moving along a predetermined motion trajectory to a first spatial orientation relative to the straight scanning trajectory and to a second spatial orientation relative to the straight scanning trajectory, respectively.

[0013] According to some embodiments of this application, the X-ray sources of the plurality of imaging units are all located on a first side relative to the transmission device along a first direction, and the detectors of the plurality of imaging units are located on a second side relative to the transmission device along the first direction, wherein the first side and the second side are opposite sides of the transmission device along the first direction.

[0014] According to some embodiments of this application, the X-ray sources of at least two of the plurality of imaging units are located on a first side relative to the transmission device along a first direction, and the detectors of the plurality of imaging units are located on a second side relative to the transmission device along the first direction, the first side and the second side being opposite sides of the transmission device along the first direction; the X-ray source of at least one of the plurality of imaging units is located on a third side relative to the transmission device along a second direction, and the detector of at least one of the plurality of imaging units is located on a fourth side relative to the transmission device along the second direction, the third side and the fourth side being opposite sides of the transmission device along the second direction, the second direction being perpendicular to the first direction.

[0015] According to some embodiments of this application, the straight-line scanning trajectory includes a first segment of straight-line scanning trajectory; the first ray source and the second ray source are configured such that, during the movement of the scanned object along the first segment of straight-line scanning trajectory, the first ray source and the second ray source respectively emit ray beams to scan the scanned object.

[0016] According to some embodiments of this application, the straight-line scanning trajectory includes a first straight-line scanning trajectory and a second straight-line scanning trajectory, the first straight-line scanning trajectory and the second straight-line scanning trajectory are parallel to each other, and the scanning object moves in opposite directions in the first straight-line scanning trajectory and the second straight-line scanning trajectory; the first imaging unit is configured such that, during the movement of the scanning object along the first straight-line scanning trajectory, the ray source of the first imaging unit is located in a first spatial orientation to scan the scanning object from the first spatial direction; the second imaging unit is configured such that, during the movement of the scanning object along the second straight-line scanning trajectory, the ray source of the second imaging unit is located in a second spatial orientation to scan the scanning object from the second spatial direction.

[0017] According to some embodiments of this application, the plurality of imaging units further includes a third imaging unit and a fourth imaging unit. The ray source of the third imaging unit is located in a third spatial orientation relative to the straight scanning trajectory to scan the object from the third spatial direction. The ray source of the fourth imaging unit is located in a fourth spatial orientation relative to the straight scanning trajectory to scan the object from the fourth spatial direction. Any two of the first spatial direction, the second spatial direction, the third spatial direction, and the fourth spatial direction are different from each other.

[0018] According to some embodiments of this application, the X-ray beam emitted by the X-ray source of the third imaging unit forms a third scanning main sector, and the X-ray beam emitted by the X-ray source of the fourth imaging unit forms a fourth scanning main sector, wherein any two of the first scanning main sector, the second scanning main sector, the third scanning main sector, and the fourth scanning main sector are located in different planes.

[0019] According to some embodiments of this application, the planes containing any two of the first scanning main sector, the second scanning main sector, the third scanning main sector, and the fourth scanning main sector intersect each other.

[0020] According to some embodiments of this application, the projections of the first scanning main sector and the third scanning main sector on the plane where the detector's detection surface is located are parallel to each other; and / or, the projections of the second scanning main sector and the fourth scanning main sector on the plane where the detector's detection surface is located are parallel to each other; and / or, the projections of the first scanning main sector and the second scanning main sector on the plane where the detector's detection surface is located are perpendicular to each other; and / or, the projections of the third scanning main sector and the fourth scanning main sector on the plane where the detector's detection surface is located are perpendicular to each other.

[0021] According to some embodiments of this application, the straight-line scanning trajectory includes a first straight-line scanning trajectory and a second straight-line scanning trajectory, wherein the first straight-line scanning trajectory and the second straight-line scanning trajectory are perpendicular to each other; the first imaging unit and the third imaging unit are configured such that, during the movement of the scanned object along the first straight-line scanning trajectory, the ray source of the first imaging unit is located in a first spatial orientation to scan the scanned object from the first spatial direction, and the ray source of the third imaging unit is located in a third spatial orientation to scan the scanned object from the third spatial direction; the second imaging unit and the fourth imaging unit are configured such that, during the movement of the scanned object along the second straight-line scanning trajectory, the ray source of the second imaging unit is located in a second spatial orientation to scan the scanned object from the second spatial direction, and the ray source of the fourth imaging unit is located in a fourth spatial orientation to scan the scanned object from the fourth spatial direction.

[0022] According to some embodiments of this application, the linear scanning trajectory includes a first linear scanning trajectory, a second linear scanning trajectory, a third linear scanning trajectory, and a fourth linear scanning trajectory. The first and second linear scanning trajectories are perpendicular to each other, and the first and third linear scanning trajectories are parallel to each other. The scanning object moves in opposite directions in the first and third linear scanning trajectories. The second and fourth linear scanning trajectories are parallel to each other, and the scanning object moves in opposite directions in the second and fourth linear scanning trajectories. The first imaging unit is configured to: during the movement of the scanning object along the first linear scanning trajectory, the first... An imaging unit has its X-ray source located in a first spatial orientation to scan the object from the first spatial direction; a second imaging unit is configured such that, during the movement of the object along a second straight-line scanning trajectory, its X-ray source is located in a second spatial orientation to scan the object from the second spatial direction; a third imaging unit is configured such that, during the movement of the object along a third straight-line scanning trajectory, its X-ray source is located in a third spatial orientation to scan the object from the third spatial direction; and a fourth imaging unit is configured such that, during the movement of the object along a fourth straight-line scanning trajectory, its X-ray source is located in a fourth spatial orientation to scan the object from the fourth spatial direction.

[0023] According to some embodiments of this application, the X-ray sources of the first and second imaging units in the plurality of imaging units are both located on a first side relative to the transmission device along a first direction, and the detectors of the plurality of imaging units are located on a second side relative to the transmission device along the first direction, the first side and the second side being opposite sides of the transmission device along the first direction; the plurality of imaging units further includes a third imaging unit, the X-ray source of the third imaging unit being located on a third side relative to the transmission device along a second direction, and the detector of at least one of the plurality of imaging units being located on a fourth side relative to the transmission device along the second direction, the third side and the fourth side being opposite sides of the transmission device along the second direction, the second direction being perpendicular to the first direction; the third imaging unit scans the scanned object from a spatial direction dominated by the second direction, and the first and second imaging units scan the scanned object from a spatial direction dominated by the first direction.

[0024] According to some embodiments of this application, the X-ray beam emitted by the X-ray source of the third imaging unit forms a third scanning main sector, and any two of the first scanning main sector, the second scanning main sector, and the third scanning main sector are located in different planes.

[0025] According to some embodiments of this application, the planes containing any two of the first scanning main sector, the second scanning main sector, and the third scanning main sector intersect each other.

[0026] According to some embodiments of this application, at least one segment of the linear scanning trajectory extends along a third direction, wherein any two of the first direction, the second direction, and the third direction are perpendicular to each other; the first scanning main sector is parallel to a first plane, or forms a first predetermined angle with the first plane, the first predetermined angle being greater than 0° and less than 90°, and the first plane is a plane formed by the intersection of the first direction and the third direction; and / or, the second scanning main sector is parallel to a second plane, or forms a second predetermined angle with the second plane, the first predetermined angle being greater than 0° and less than 90°, and the second plane is a plane formed by the intersection of the first direction and the second direction; and / or, the third scanning main sector is parallel to a third plane, or forms a third predetermined angle with the third plane, the third predetermined angle being greater than 0° and less than 90°, and the third plane is a plane formed by the intersection of the second direction and the third direction.

[0027] According to some embodiments of this application, the X-ray source of the first imaging unit and the X-ray source of the second imaging unit are independently arranged and spaced apart along the second direction; or, the X-ray source of the second imaging unit is formed by moving the X-ray source of the first imaging unit located in the first spatial orientation along a predetermined motion trajectory to the second spatial orientation, wherein the motion trajectory is a straight line trajectory parallel to the second direction.

[0028] According to some embodiments of this application, the projection data acquired by the second imaging unit is used to supplement the projection data acquired by the first imaging unit within the cone angle range.

[0029] According to some embodiments of this application, the straight-line scanning trajectory includes a first straight-line scanning trajectory; the first imaging unit is configured such that, during the movement of the scanned object along the first straight-line scanning trajectory, the ray source of the first imaging unit is located in a first spatial orientation to scan the scanned object from the first spatial direction; the second imaging unit is configured such that, during the movement of the scanned object along the first straight-line scanning trajectory, the ray source of the second imaging unit is located in a second spatial orientation to scan the scanned object from the second spatial direction; and the third imaging unit is configured such that, during the movement of the scanned object along the first straight-line scanning trajectory, the ray source of the third imaging unit is located in a third spatial orientation to scan the scanned object from the third spatial direction.

[0030] According to some embodiments of this application, the straight-line scanning trajectory includes a first straight-line scanning trajectory and a second straight-line scanning trajectory, the first straight-line scanning trajectory and the second straight-line scanning trajectory are parallel to each other, and the scanning object moves in opposite directions in the first straight-line scanning trajectory and the second straight-line scanning trajectory; the first imaging unit is configured such that, during the movement of the scanning object along the first straight-line scanning trajectory, the ray source of the first imaging unit is located in a first spatial orientation to scan the scanning object from the first spatial direction; the second imaging unit is configured such that, during the movement of the scanning object along the second straight-line scanning trajectory, the ray source of the second imaging unit is located in a second spatial orientation to scan the scanning object from the second spatial direction; the third imaging unit is configured such that, during the movement of the scanning object along at least one of the first straight-line scanning trajectory and the second straight-line scanning trajectory, the ray source of the third imaging unit is located in a third spatial orientation to scan the scanning object from the third spatial direction.

[0031] According to some embodiments of this application, the ray source of the second imaging unit is formed by moving the ray source of the first imaging unit located in the first spatial orientation along a predetermined motion trajectory to the second spatial orientation.

[0032] According to some embodiments of this application, the second imaging unit is configured such that, during the movement of the scanned object along the second straight scanning trajectory, the ray source of the second imaging unit moves along a predetermined motion trajectory, so that the second scanning main sector scans the scanned object from multiple different spatial directions.

[0033] According to some embodiments of this application, the plane containing the motion trajectory is parallel to a third plane, which is a plane formed by the intersection of a second direction and a third direction; or the plane containing the motion trajectory is parallel to a second plane, which is a plane formed by the intersection of a first direction and a second direction; or the plane containing the motion trajectory is parallel to a first plane, which is a plane formed by the intersection of a first direction and a third direction.

[0034] According to some embodiments of this application, the motion trajectory includes at least one of a circular trajectory, an arc trajectory, or a straight trajectory.

[0035] According to some embodiments of this application, the system further includes an imaging device configured to generate multi-spatial-direction tomographic images by jointly utilizing projection data obtained by scanning the scanned object through the plurality of spatial directions.

[0036] According to a second aspect of this application, a scanning imaging method using the system described in the first aspect is provided, the method comprising: controlling the scanning object to move along a straight scanning trajectory; controlling a plurality of imaging units to scan the scanning object from multiple spatial directions during the movement of the scanning object along the straight scanning trajectory to obtain projection data corresponding to the plurality of spatial directions; and generating a multi-spatial-direction tomographic image of at least one target detection region in the scanning object based on the projection data corresponding to the plurality of spatial directions. Attached Figure Description

[0037] The above and other objects, features and advantages of this application will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0038] Figure 1 An exemplary schematic diagram of a CT imaging system based on circular orbit imaging is shown;

[0039] Figure 2A A schematic diagram of a two-segment linear CT imaging system according to some exemplary embodiments of this application is shown.

[0040] Figure 2B It shows Figure 2A A planar schematic diagram of the angle range of a two-segment linear CT imaging system;

[0041] Figure 2C It shows Figure 2A A three-dimensional schematic diagram of the angle range of a two-segment linear CT imaging system;

[0042] Figure 3A The schematic diagram illustrates the structure of a linear CT imaging system with multi-spatial-direction imaging capability according to some exemplary embodiments of this application;

[0043] Figure 3B This schematically illustrates the positions of the transport device and the scanned object in a linear CT imaging system according to some exemplary embodiments of this application;

[0044] Figure 3C The schematic diagram illustrates the structure of a linear CT imaging system with multi-spatial-direction imaging capability according to some other exemplary embodiments of this application;

[0045] Figure 4A The schematic diagram illustrates the structure of a linear CT imaging system according to some exemplary embodiments of this application;

[0046] Figure 4B This schematically illustrates a structural diagram of a linear CT imaging system according to some exemplary embodiments of the present application.

[0047] Figure 5 The diagram illustrates the projection of each scanning main sector onto the plane containing the detector detection surface according to some exemplary embodiments of this application;

[0048] Figure 6A This schematically illustrates a structural diagram of a linear CT imaging system that performs scanning imaging based on a first direction Y and a second direction X, according to some exemplary embodiments of this application.

[0049] Figure 6B This schematically illustrates a structural diagram of a linear CT imaging system that performs scanning imaging based on a first direction Y and a second direction X, according to some other exemplary embodiments of this application.

[0050] Figure 6C This schematically illustrates a structural diagram of a linear CT imaging system that performs scanning imaging based on a first direction Y and a second direction X, according to some exemplary embodiments of this application.

[0051] Figure 7 A flowchart illustrating a scanning imaging method according to some exemplary embodiments of this application is shown schematically;

[0052] Figure 8 A block diagram of an electronic device suitable for implementing the methods described above, according to an embodiment of this application, is illustrated schematically. Detailed Implementation

[0053] The embodiments of this application will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of this application. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of this application for ease of explanation. However, it will be apparent that one or more embodiments may be implemented without these specific details. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this application.

[0054] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0055] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0056] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0057] It should be noted that, unless otherwise specified, the terms "first," "second," etc., used in this application are merely for the convenience of referring to different components, such as different imaging units, during the description process, and should not be construed as imposing any form of limitation on the structure of the imaging unit.

[0058] Computed tomography (CT) is an imaging technique that reconstructs the internal structure of a scanned object by acquiring projection data of the object in different directions and based on this projection data. This technology can acquire information about the internal structure of a scanned object without destructive testing, and therefore has been widely used in various fields such as industrial non-destructive testing, medical imaging, security inspection, materials analysis, and scientific research experiments.

[0059] In existing CT imaging systems, some methods employ imaging techniques that scan a closed trajectory around the object being scanned. Examples include circular or spiral trajectory imaging.

[0060] Figure 1A schematic diagram of a CT imaging system based on circular or helical orbit imaging is shown as an example. Figure 1 As shown, the CT imaging system may include a transport device 110 for carrying or transporting the scanned object 120, a radiation source 1 and a detector 2 disposed within a gantry 150, and a data processing device 130 and a terminal device 140 for controlling the scanning and processing the reconstruction data. In this CT imaging system, the radiation source 1 and the detector 2 rotate around the scanned object 120, or the scanned object 120 rotates relative to the radiation source 1 and the detector 2, thereby acquiring projection data at multiple angular positions along a closed trajectory and completing three-dimensional reconstruction.

[0061] However, while the closed-track scanning imaging method described above is relatively mature, it has significant limitations in long objects, plate-shaped objects, and online inspection scenarios. Firstly, because the X-ray beam typically has a non-negligible cone angle, when the axial dimension of the scanned object is large, circular track scanning easily introduces significant axial cone angle artifacts in the reconstruction results, affecting the imaging quality of the axial structure. Secondly, for plate-shaped objects, long strip-shaped or columnar objects, or workpieces that need to be continuously transported in the production line, rotating around the object usually requires a large rotation space and scanning radius, resulting in complex equipment structure, difficult layout, complex motion control, and low inspection efficiency. To further mitigate cone angle artifacts, some technologies have adopted more complex motion methods such as helical track scanning, but this further increases the mechanical complexity and control difficulty of the system, hindering high-speed inspection and online integration.

[0062] Based on the aforementioned issues, linear CT imaging systems have gradually become an important technical approach suitable for long workpieces and online inspection scenarios. Linear CT imaging systems refer to systems where the object being scanned, the X-ray source, and the detector move relatively in a straight line along a predetermined direction during the scanning process, acquiring projection data at different positions to achieve tomographic imaging. Compared to closed-track scanning methods, linear CT imaging systems do not rely on rotation around the object, have a more compact overall structure, simpler movement, and are easier to couple with transport mechanisms or sliding mechanisms. Therefore, they are particularly suitable for non-destructive testing of plate-shaped objects, long objects, and workpieces that pass continuously online.

[0063] However, while linear CT imaging systems offer advantages in terms of equipment structure and application scenario adaptability, their specific layout is still limited by the form of their scanning trajectory and projection sampling method. Generally speaking, linear CT imaging systems can be categorized into single-segment linear CT and multi-segment linear CT based on the number of scanning trajectories and their spatial arrangement. Single-segment linear CT is a more basic implementation, where only one straight scanning segment is set up during the imaging process. The scanned object, the X-ray source, and the detector move relative to each other along this single straight line, and a set of projection data is acquired at different positions within the straight scanning segment for subsequent tomographic reconstruction.

[0064] In single-segment linear CT, because the scanning trajectory is limited to a straight line in a single direction, the range of changes in the projection direction formed by the system during the scanning process is relatively limited. This results in incomplete sampling of the projection data in angular space, making the reconstruction results prone to finite angle artifacts. These finite angle artifacts typically manifest as blurred edges, structural stretching, local distortion, and grayscale instability. They are particularly susceptible to affecting the imaging results of directional slender defects, oblique boundaries, or complex three-dimensional structures due to insufficient acquisition of projection information in relevant directions.

[0065] To mitigate the limited-angle artifacts in single-segment linear CT imaging systems, some techniques have proposed multi-segment linear CT imaging schemes. These schemes expand the overall imaging angle range by arranging multiple linear scanning segments in different directions, acquiring projection data separately for each segment, and then jointly reconstructing multiple sets of projection data.

[0066] Figure 2A A schematic diagram of a two-segment linear CT imaging system according to some exemplary embodiments of this application is shown. Figure 2B It shows Figure 2A A planar schematic diagram of the angle range of a two-segment linear CT imaging system; Figure 2C It shows Figure 2A A three-dimensional schematic diagram of the two-segment linear CT imaging angle range.

[0067] like Figure 2AAs shown, in a linear CT imaging system, two linear scanning trajectories can be set. For ease of description, these two linear scanning trajectories are referred to as the first linear scanning trajectory and the second linear scanning trajectory, respectively. Exemplarily, the first linear scanning trajectory extends along a first direction, and the second linear scanning trajectory extends along a second direction, with the first and second directions intersecting. In the first linear scanning trajectory, the scanned object 120 and the source-detector assembly including the X-ray source 1 and the detector 2 have relative linear motion along the first direction. In the second linear scanning trajectory, the scanned object 120 and the source-detector assembly including the X-ray source 1 and the detector 2 have relative linear motion along the second direction.

[0068] In the first straight-line scanning trajectory, the X-ray beam emitted by X-ray source 1 covers the first scanning fan-angle range along the fan-angle direction of the X-ray beam. For example, the angle between the X-ray beam emitted by X-ray source 1 and the first scanning main fan-angle α1 in the first direction is assumed to be α1. Figure 2A The two arrowed lines connected to X-ray source 1 represent the boundary range of the X-ray beam emitted by X-ray source 1. The angle between the two arrowed lines is the first scanning main sector angle. In the second straight-line scanning trajectory, the X-ray beam emitted by X-ray source 1 covers the second scanning sector angle range along the sector angle direction of the X-ray beam. For example, the angle between the X-ray beam emitted by X-ray source 1 in the second direction is the second scanning main sector angle α2. Let... Figure 2A The two arrowed lines connected to X-ray source 1 represent the boundary range of the X-ray beam emitted by X-ray source 1. The included angle between the two arrowed lines is the main fan angle of the second scan. By combining the angle ranges of the fan angle directions corresponding to the two straight-line CT scans, the overall angle coverage range of the fan angle direction can be expanded to a certain extent, thereby improving the problem of limited angle artifacts under single-segment straight-line CT scan conditions.

[0069] Combined with reference Figures 2A to 2C In multi-segment linear CT imaging systems, scanning segments with different directions are typically set within the same imaging plane, causing the projection direction to change within that imaging plane. In other words, the linear CT scan in the first linear scanning trajectory and the linear CT scan in the second linear scanning trajectory have different linear motion directions and scanning angles along different directions, but the two linear CT scans still belong to the compensation and expansion of the angular space in the sector direction within the same plane.

[0070] from Figure 2C It can be seen more clearly that although the first angular range α1 and the second angular range α2 can be superimposed to form a larger fan-angle coverage area, the expanded area is still the angular range within the same imaging plane. In other words, this multi-segment linear CT scanning imaging system mainly improves the problem of insufficient in-plane sampling, and its imaging geometry is still basically limited to a coplanar arrangement structure.

[0071] It should be understood that the limitations of this coplanar multi-segment linear CT imaging system are particularly evident in 3D imaging. Because the X-ray source and detector in each scan segment are located within the same imaging plane, or their equivalent projection centers are constrained by the same plane, the changes in projection direction are mainly concentrated within that plane; for spatial directions perpendicular to the imaging plane, there is a lack of independent and controllable sampling degrees of freedom. Although the X-ray beam itself has a certain cone angle, objectively introducing a small amount of out-of-plane directional components, these components are not actively designed and controlled as independent imaging dimensions, but rather coupled with the in-plane projection viewpoint, source / detector position, and the spatial position of the scanned object. Therefore, this type of out-of-plane information is often unstable, cannot be independently adjusted, and makes it difficult to form truly effective 3D complementary sampling between different scan segments.

[0072] While coplanar multi-segment linear CT imaging systems can mitigate in-plane finite-angle artifacts to some extent, their ability to characterize structures with different spatial orientations remains significantly different. For example, for structures extending along the imaging plane, their projection changes are more easily captured by multi-segment scanning; however, for structures tilted towards the imaging plane or extending outwards, the information provided by existing coplanar scanning schemes is still insufficient, leading to a strong dependence of the reconstruction results on the structural orientation. This ultimately manifests as clearer boundaries in some directions, while boundaries, grayscale distortion, or enhanced artifacts occur in other directions, making it difficult to guarantee the consistency of sharpness and grayscale in the reconstructed image in three-dimensional space.

[0073] Based on this, embodiments of this application provide a linear CT imaging system and scanning imaging method with multi-spatial direction imaging capabilities, which are applicable to defect detection of scanned objects in multiple fields such as industrial inspection or security inspection, and can obtain targeted scanning imaging of the region of interest (ROI) of the scanned object.

[0074] The embodiments of this application still employ linear CT scanning as a whole, eliminating the need for the X-ray source and detector to rotate completely around the scanned object, and avoiding complex motion forms such as helical tracks. By arranging multiple imaging units in a non-coplanar space, and by varying the pose of some imaging units within a limited range, multi-spatial projection data can be acquired. Therefore, the spatial sampling range of linear CT can be expanded within a limited installation space, while maintaining a compact system structure, relatively simple motion forms, and ease of integration with online detection scenarios, offering good engineering feasibility.

[0075] The embodiments of this application will be described in detail below using a scanning imaging system for a specific tissue of a living organism or an industrial part as an example. It should be understood that the embodiments of this application are not limited to imaging scenarios for a specific tissue of a living organism or an industrial part; they can be applied to various scanning imaging scenarios. For example, they can be applied to scanning imaging scenarios involving various different inspection objects, including but not limited to vehicle scanning imaging, luggage / parcel scanning imaging, human or animal scanning imaging, organ / tissue scanning imaging, small object scanning imaging, and large object scanning imaging such as containers. It should be noted that the description of scanning imaging scenarios here is not exhaustive, and the exemplary descriptions below should not be construed as limiting the scope of protection of this application.

[0076] Figure 3A The schematic diagram illustrates the structure of a linear CT imaging system with multi-spatial-direction imaging capability according to some exemplary embodiments of this application; Figure 3B This schematically illustrates the positions of the transport device and the scanned object in a linear CT imaging system according to some exemplary embodiments of this application; Figure 3C The schematic diagram illustrates a linear CT imaging system with multi-spatial-direction imaging capability according to some other exemplary embodiments of this application. (Refer to...) Figure 3A and Figure 3C In the embodiments of this application, the linear CT imaging system 300 can be used to scan and image the object 310. Exemplarily, the object 310 can be any of the following: plate-like object, sheet-like object, layered object, long-sized object, regular or irregular solid object, such as sheet metal, composite material components, electronic packaging components, and laminated structural components in industrial inspection, or packages, boxes, and thin sheet-like carriers in security inspection scenarios. The embodiments of this application do not limit the specific type of the object 310.

[0077] Reference Figure 3B The linear CT imaging system 300 may include a transport device 320. The transport device 320 is used to move the scanned object 310 along a predetermined linear scanning trajectory. In embodiments of this application, the placement of the scanned object 310 on the transport device 320 can be configured according to its size and shape, the location of the area to be detected, and detection requirements. For example, for a scanned object 310 with a long side and a short side, its long side can be placed along the extension direction of the transport device 320, or its short side can be placed along the extension direction of the transport device 320. Embodiments of this application do not limit the placement of the scanned object 310.

[0078] Reference Figure 3A and Figure 3CThe linear CT imaging system 300 may include multiple imaging units. Each of the multiple imaging units includes at least one X-ray source and at least one detector, used to perform X-ray scanning on the scanned object 310 from different spatial directions during the movement of the scanned object 310 along the linear scanning trajectory, in order to obtain corresponding projection data.

[0079] Continue to refer to Figure 3A and Figure 3C Multiple imaging units may include at least a first imaging unit 331 and a second imaging unit 332. It should be noted that, for ease of explanation, Figure 3A and Figure 3C The illustration shows only two imaging units. This illustration is mainly used to demonstrate the basic concept of multi-spatial direction imaging in the embodiments of this application. In other embodiments, the multiple imaging unit groups may include three, four or more imaging units, and the embodiments of this application do not limit this.

[0080] For example, the first imaging unit 331 includes a first X-ray source 3311 and a first detector 3312, and the second imaging unit 332 includes a second X-ray source 3321 and a second detector 3322. Correspondingly, the first X-ray source 3311 is used to emit a X-ray beam, and the first detector 3312 is used to detect the X-ray beam after passing through the scanned object 310; the second X-ray source 3321 is used to emit a X-ray beam, and the second detector 3322 is used to detect the X-ray beam after passing through the scanned object 310.

[0081] For example, the radiation beam can be an X-ray beam, but this application does not limit this. The detector can be a linear array detector, an area array detector, or other detectors capable of detecting radiation, and this application does not limit this either.

[0082] It should be noted that, in the illustrations, the detector in this embodiment is represented by a straight line; this is merely illustrative and not intended to limit the structure or form of the detector. It is understood that the detectors corresponding to multiple imaging units can be the same or correspond to multiple units separately.

[0083] Continue to refer to Figure 3A and Figure 3C The first imaging unit 331 and the second imaging unit 332 are spaced apart in the area above the scanned object 310 and face the scanned object 310 in different orientations. Thus, the first imaging unit 331 and the second imaging unit 332 can perform scanning imaging on the scanned object 310 from different spatial directions as the scanned object 310 moves along a straight scanning trajectory.

[0084] In the embodiments of this application, multiple imaging units are located in different spatial orientations relative to the linear scanning trajectory, so as to form imaging capabilities in different spatial directions.

[0085] Specifically, such as Figure 3A and Figure 3C As shown, the first ray source 3311 is located in a first spatial orientation relative to the straight scanning trajectory to scan the object 310 from the first spatial direction. The second ray source 3321 is located in a second spatial orientation relative to the straight scanning trajectory to scan the object 310 from the second spatial direction. The first spatial direction is different from the second spatial direction. The "spatial orientation relative to the straight scanning trajectory" mentioned here can be understood as the relative position and orientation of the ray sources arranged around it in three-dimensional space with the straight scanning trajectory as a reference. Since the first ray source 3311 and the second ray source 3321 are located in different spatial orientations, the corresponding main ray directions are different when they scan the object 310.

[0086] In this embodiment of the application, the X-ray beam emitted by the first X-ray source 3311 forms a first scanning main sector S1, and the X-ray beam emitted by the second X-ray source 3321 forms a second scanning main sector S2, and the first scanning main sector S1 and the second scanning main sector S2 are located in different planes.

[0087] It should be noted that the scanning main sector mentioned in this article refers to the imaging plane used to characterize the main scanning direction of the corresponding imaging unit during scanning imaging. For any imaging unit, its scanning main sector can be determined by the following geometric relationship: the scanning main sector passes through the focal point of the corresponding X-ray source and includes the main X-ray direction and the fan beam unfolding direction of the corresponding imaging unit. In other words, the scanning main sector is not an arbitrarily selected reference plane, but an imaging plane corresponding to the main X-ray imaging direction of the imaging unit.

[0088] Furthermore, the direction of the main ray can be from the corresponding ray source to the center of the receiving area of ​​the corresponding detector, or it can be from the corresponding ray source to the center of a preset scanning center, a preset imaging center, or the center of the region of interest; the fan beam expansion direction can be determined by the directions of the boundary rays on both sides of the main ray. The direction of the boundary rays can be determined comprehensively based on the structural parameters of the corresponding ray source, its installation attitude, collimation method, and the spatial position of the target scanning area.

[0089] Specifically, for the first imaging unit 331, the first scanning main sector S1 can be understood as a fan-shaped plane formed by the first fan-beam rays emitted from the first X-ray source 3311 in the direction of the main ray; for the second imaging unit 332, the second scanning main sector S2 can be understood as a fan-shaped plane formed by the second fan-beam rays emitted from the second X-ray source 3321 in the direction of the main ray. Since the first imaging unit 331 and the second imaging unit 332 are located in different spatial orientations relative to the linear scanning trajectory, the first scanning main sector S1 and the second scanning main sector S2 have different orientations in space and are located in different planes.

[0090] In the embodiments of this application, the plane containing the first scanning main sector S1 and the plane containing the second scanning main sector S2 can intersect. When they intersect, the line of intersection can pass through a preset scanning area of ​​the scanned object 310 or through the location of the Region of Interest (ROI). Thus, the first imaging unit 331 and the second imaging unit 332 can scan the same or adjacent areas from different spatial directions, which helps to enhance the projection response of the area in different spatial directions and improve the imaging characterization capability of defect boundaries, internal interfaces, and complex orientation structures. Especially for tilted cracks in plate-like objects, layered defects in layered structures, or internal anomalous areas with spatial extension characteristics, multi-directional sampling formed by intersecting planes can improve the imaging integrity of local areas.

[0091] Reference Figure 3A In some embodiments, the angle θ between the plane where the first scanning main sector S1 is located and the plane where the second scanning main sector S2 is located can be greater than 0° and less than 90°.

[0092] In this embodiment, the specific value of the included angle θ can be selected based on the shape and size of the scanned object 310, the location of the ROI, the desired reconstruction resolution, and the system installation space. For example, for thinner plate-shaped objects, a relatively small included angle can be used to enable the two imaging units to perform complementary sampling of structural changes in the thickness direction and the surface direction of the plate; for scanned objects with a certain thickness or complex internal orientation structures, the included angle can be appropriately increased to enhance the ability to distinguish structures in different spatial directions.

[0093] Furthermore, when the included angle θ is within the range of greater than 0° and less than 90°, the first scanning main sector S1 and the second scanning main sector S2 can form a converging or semi-converging spatial layout on one side of the scanned object 310. This layout helps to improve the effectiveness of multi-directional imaging without significantly increasing the lateral space occupied by the system. For online inspection scenarios, this acute-angle spatial arrangement also facilitates the centralized deployment of the imaging unit group 330 on one side or above the conveying device 320, thereby benefiting engineering deployment and equipment integration.

[0094] In embodiments of this application, multiple imaging units may include at least two imaging units that are independently configured. Specifically, different imaging units may be configured separately in terms of hardware structure, each having a corresponding ray emitting component and ray receiving component, and are installed in predetermined positions in a mutually separate manner in the system layout. Figure 3A For example, the first imaging unit 331 and the second imaging unit 332 can be two imaging units that are set independently of each other. They are located in different spatial orientations relative to the same straight line scanning trajectory and undertake scanning imaging tasks in different spatial directions.

[0095] In some embodiments, multiple imaging units that are independently arranged can be fixedly mounted on a frame or support structure and maintain their spatial position during the scanning process. The scanning object 310 is driven by the conveying device 320 to pass through the imaging area along a straight scanning trajectory.

[0096] In the embodiments of this application, at least some of the imaging units can also be formed by the same imaging unit undergoing spatial orientation changes during the scanning process. That is, multiple imaging units do not necessarily require that they all simultaneously correspond to multiple physically independent imaging modules in hardware; the same imaging unit can move to different spatial orientations at different scanning stages and perform scanning imaging at different spatial orientations. Therefore, the different spatial scanning states corresponding to the same imaging unit at different time periods can also be regarded as different imaging units among the multiple imaging units.

[0097] by Figure 3C For example, the same imaging unit can first be positioned in a first spatial orientation relative to the straight scanning trajectory to perform a first-stage scan of the scanning object 310; subsequently, the imaging unit can move along a predetermined motion trajectory ( Figure 3C The arc-shaped dashed line in the image moves to the second spatial orientation, and then the second stage of scanning is performed on the scanned object 310. Since the spatial orientation, main ray direction, and main scanning sector are different for the two scanning stages, they can correspond to the first imaging unit 331 and the second imaging unit 332, respectively. In this way, multi-spatial direction sampling can be achieved with a reduction in the number of hardware components.

[0098] In this embodiment, the spatial orientation transformation can include translation, rotation, swinging, lifting, rotation around a predetermined axis, or a combination of at least two of the above movements. For example, the same imaging unit can change the direction of the main ray by rotating around a certain axis; it can also change its spatial position relative to the straight scanning trajectory by moving along an arc-shaped trajectory or a broken line trajectory; and it can also change the spatial orientation of the scanning main sector by switching between different height positions.

[0099] Furthermore, in the embodiments of this application, the first radiation source 3311 and the second radiation source 3321 can be set independently of each other, or they can correspond to different spatial imaging states formed by the same physical radiation source at different scanning stages. When the first radiation source 3311 and the second radiation source 3321 are set independently of each other, they can be arranged at intervals along a predetermined spatial trajectory. The spatial trajectory can be any one of a straight line, a broken line, an arc, a curve, a piecewise curve, or other preset spatial paths.

[0100] When the first X-ray source 3311 and the second X-ray source 3321 correspond to the same physical X-ray source, the X-ray source can move along a predetermined trajectory and reach the first spatial orientation and the second spatial orientation respectively at different scanning stages. When the X-ray source is located at the first spatial orientation and performs scanning imaging, it can correspond to the first imaging unit 331; when the X-ray source is located at the second spatial orientation and performs scanning imaging, it can correspond to the second imaging unit 332. It should be noted that the first spatial orientation and the second spatial orientation are used to characterize the difference in target spatial position and scanning direction during scanning imaging, and do not limit the initial position, termination position or specific movement sequence of the X-ray source.

[0101] In some exemplary embodiments, the detector may remain stationary while the radiation source moves along a predetermined trajectory.

[0102] In other embodiments, multiple independently configured imaging units and imaging unit states formed by spatial orientation changes of the same imaging unit can be used simultaneously. In other words, the multiple imaging units in the system can be partially derived from multiple independent hardware modules, or partially derived from the orientation changes of the same hardware module at different scanning stages.

[0103] It should be noted that, for ease of describing direction, the relative positions of the components in the system can be determined using the coordinate system in which the first imaging unit 331, including the first X-ray source 3311 and the first detector 3312, is located. For example, in Figure 3A In this configuration, the direction from which the first detector 3312 faces the first radiation source 3311 is defined as the first direction Y. In this case, the transmission device 320 has two opposing spatial regions on either side of the first direction Y. One side can serve as the first side for arranging radiation sources for multiple imaging units; the other side can serve as the second side for arranging multiple detectors corresponding to it.

[0104] Furthermore, the extension direction of the conveying device 320 can be taken as the third direction Z; and the direction perpendicular to the first direction Y and the third direction Z can be taken as the second direction X, that is... Figure 3AThe scanning object 310 is located in the width direction. In this case, the conveying device 320 also has two opposing spatial regions on either side in the second direction X. One side can serve as the third side; the other side can serve as the fourth side. It should be noted that the definitions and descriptions of various coordinate systems and directions in the embodiments of this application are merely exemplary descriptions for the convenience of describing the embodiments of this application, and they are not intended to limit the embodiments of this application. To facilitate the explanation of the relative positional relationships of the components in the system, the above-mentioned reference coordinate system can be used in other embodiments of this application, and will not be repeated here.

[0105] In embodiments of this application, the X-ray sources of multiple imaging units can be located on a first side relative to the transmission device 320 along the first direction Y, and the detectors of multiple imaging units are located on a second side relative to the transmission device 320 along the first direction Y. The first side and the second side are located on opposite sides of the transmission device 320 along the first direction Y. Based on this arrangement, the X-ray beam emitted by each imaging unit can pass through the scanning object 310 located on the transmission device 320 from the first side and be received by the corresponding detector located on the second side.

[0106] For example, the first radiation source 3311 and the second radiation source 3321 can both be disposed on the first side of the transmission device 320 in the first direction Y, and the first detector 3312 and the second detector 3322 can both be disposed on the second side of the transmission device 320 in the first direction Y.

[0107] In some embodiments, the linear scanning trajectory may include a first segment of linear scanning trajectory. The first X-ray source 3311 and the second X-ray source 3321 may be configured such that, during the movement of the scanned object 310 along the first segment of linear scanning trajectory, the first X-ray source 3311 and the second X-ray source 3321 respectively emit X-ray beams to scan the scanned object 310. Wherein, when the scanned object 310 is transported or moves relatively linearly along the same segment of linear scanning trajectory, the first imaging unit 331 and the second imaging unit 332 may perform synchronous scanning or time-division scanning of the scanned object 310 from different spatial directions.

[0108] Combination Figure 3A It can be seen that the first straight-line scanning trajectory can be a straight-line scanning trajectory along the second direction X. During the continuous movement of the scanned object 310 along the first straight-line scanning trajectory, the X-ray beam emitted by the first X-ray source 3311 and the X-ray beam emitted by the second X-ray source 3321 can pass through the scanned object 310 from different spatial directions, and the projection data is received by their respective corresponding detectors. Therefore, even if the scanned object 310 only completes its movement along a single straight-line scanning trajectory, the system can still acquire projection information from different spatial directions during the same scanning process.

[0109] Combination Figure 3CIt can be seen that the straight-line scanning trajectory can also include a first straight-line scanning trajectory and a second straight-line scanning trajectory. The first and second straight-line scanning trajectories are parallel to each other, and the scanning object 310 moves in opposite directions in the first and second straight-line scanning trajectories. The first straight-line scanning trajectory can be the straight-line scanning trajectory corresponding to the second direction X; the second straight-line scanning trajectory can be the straight-line scanning trajectory corresponding to the opposite direction of the second direction X. In other words, the conveying device 320 can form a reciprocating or zigzag straight-line scanning path, causing the scanning object 310 to first move in one direction along the first straight-line scanning trajectory, and then move in the opposite direction along the second straight-line scanning trajectory parallel to the first straight-line scanning trajectory.

[0110] In this embodiment, the first imaging unit 331 can be configured such that, during the movement of the scanned object 310 along a first straight scanning trajectory, the X-ray source of the first imaging unit 331 is located in a first spatial orientation to scan the scanned object 310 from the first spatial direction; the second imaging unit 332 can be configured such that, during the movement of the scanned object 310 along a second straight scanning trajectory, the X-ray source of the second imaging unit 332 is located in a second spatial orientation to scan the scanned object 310 from the second spatial direction. That is, the first spatial direction corresponds to the scanning state in the first straight scanning trajectory, and the second spatial direction corresponds to the scanning state in the second straight scanning trajectory; both participate in imaging at different stages of the reciprocating movement of the scanned object 310.

[0111] Figure 4A The schematic diagram illustrates the structure of a linear CT imaging system according to some exemplary embodiments of this application; Figure 4B The schematic diagram illustrates the structure of a linear CT imaging system according to some exemplary embodiments of the present application.

[0112] like Figure 4A and Figure 4B As shown, the linear CT imaging system 500 may include a transport device (similar to the above embodiment, and will not be described again here), a scanning object 510 disposed on the transport device, and an imaging unit group. The transport device is used to move the scanning object 510 along a predetermined linear scanning trajectory. The imaging unit group includes a first imaging unit 531, a second imaging unit 532, a third imaging unit 533, and a fourth imaging unit 534. The four imaging units scan and image the scanning object 510 from different spatial orientations to obtain richer multi-spatial projection data.

[0113] In this embodiment, the X-ray source 5311 of the first imaging unit 531 is located in a first spatial orientation relative to the straight scanning trajectory to scan the object 510 from the first spatial direction; the X-ray source 5321 of the second imaging unit 532 is located in a second spatial orientation relative to the straight scanning trajectory to scan the object 510 from the second spatial direction; the X-ray source 5331 of the third imaging unit 533 is located in a third spatial orientation relative to the straight scanning trajectory to scan the object 510 from the third spatial direction; and the X-ray source 5341 of the fourth imaging unit 534 is located in a fourth spatial orientation relative to the straight scanning trajectory to scan the object 510 from the fourth spatial direction. Any two of the first, second, third, and fourth spatial directions are different from each other. That is, the four imaging units correspond to four different spatial scanning directions, thereby forming a more comprehensive spatial sampling distribution around the object 510.

[0114] For example, Figure 4A and Figure 4B The first detector 5312, the second detector 5322, the third detector 5332, and the fourth detector 5342 corresponding to the first imaging unit 531, the second imaging unit 532, the third imaging unit 533, and the fourth imaging unit 534 are also shown.

[0115] Combination Figure 4A and Figure 4B It is understood that the four imaging units can be distributed around the top and side-top of the scanned object 510. The first imaging unit 531, the second imaging unit 532, the third imaging unit 533, and the fourth imaging unit 534 can be spaced apart along a predetermined spatial trajectory, or they can be oriented towards the scanned object 510 at different angles and orientations. Since the position of the X-ray source and the direction of the main X-ray are different for each imaging unit, the four imaging units can form different spatial scanning relationships with each other.

[0116] In the embodiments of this application, the X-ray beam emitted by the first X-ray source 5311 forms a first scanning main sector S11, the X-ray beam emitted by the second X-ray source 5321 forms a second scanning main sector S12, the X-ray beam emitted by the third X-ray source 5331 forms a third scanning main sector S13, and the X-ray beam emitted by the fourth X-ray source 5341 forms a fourth scanning main sector S14. Any two of the first scanning main sector S11, the second scanning main sector S12, the third scanning main sector S13, and the fourth scanning main sector S14 are located in different planes.

[0117] The phrase "any two located in different planes" here primarily characterizes the geometric distinction between the main scanning sectors in space. In other words, in this embodiment, for any two of the first, second, third, and fourth main scanning sectors S11, their respective planes are different. This avoids the situation where, although the number of imaging units increases, the main scanning directions remain concentrated in the same plane, thereby improving the coverage capability of different spatial orientation structures within the scanned object 510.

[0118] In some embodiments, the planes containing any two of the first scanning main sector S11, the second scanning main sector S12, the third scanning main sector S13, and the fourth scanning main sector S14 may intersect each other.

[0119] Figure 5 The diagram illustrates the projection of each scanning main sector onto the plane containing the detector detection surface according to some exemplary embodiments of this application.

[0120] In the embodiments of this application, the projections L1 and L3 of the first scanning main sector S11 and the third scanning main sector S13 onto the plane Q where the detector detection surface is located can be parallel to each other; and / or, the projections L2 and L4 of the second scanning main sector S12 and the fourth scanning main sector S14 onto the plane Q where the detector detection surface is located can be parallel to each other; and / or, the projections L1 and L2 of the first scanning main sector S11 and the second scanning main sector S12 onto the plane Q where the detector detection surface is located can be perpendicular to each other; and / or, the projections L3 and L4 of the third scanning main sector S13 and the fourth scanning main sector S14 onto the plane Q where the detector detection surface is located can be perpendicular to each other.

[0121] Specifically, the projection on the plane where the detector's detection surface is located can be understood as: the projection line or projection direction relationship formed after mapping each scanning main sector along a predetermined projection direction onto the plane where the detector's detection surface is located.

[0122] In this embodiment, the projections of the first scanning main sector S11 and the third scanning main sector S13 onto the detector detection surface can be parallel to each other, indicating that the two scanning main sectors have similar sector expansion base directions in the sense of projection; the projections of the second scanning main sector S12 and the fourth scanning main sector S14 onto the detector detection surface can also be parallel to each other, thus forming another set of parallel projection relationships.

[0123] The projections of the first scanning main sector S11 and the third scanning main sector S13 onto the detector's detection surface can be perpendicular to each other, as can the projections of the second scanning main sector S12 and the fourth scanning main sector S14 onto the detector's detection surface. Through the combination of these two sets of parallel and two sets of perpendicular relationships, the four imaging units can form a layout similar to a cross-grid or orthogonally complementary pattern in projection geometry. Therefore, different imaging units can form mutually parallel sampling complements in some directions and mutually orthogonal directional distinctions in others, thereby further enhancing the system's ability to separate and represent structural information in different directions.

[0124] Continue to refer to Figure 4A In embodiments of this application, the first and second straight-line scanning trajectories can also be perpendicular to each other. Specifically, the first imaging unit 531 and the third imaging unit 533 can be configured such that, during the movement of the scanned object 510 along the first straight-line scanning trajectory, the first ray source 5311 of the first imaging unit 531 is located in a first spatial orientation to scan the scanned object 510 from the first spatial direction, and the third ray source 5331 of the third imaging unit 533 is located in a third spatial orientation to scan the scanned object 510 from the third spatial direction; the second imaging unit 532 and the fourth imaging unit 534 can be configured such that, during the movement of the scanned object 510 along the second straight-line scanning trajectory, the second ray source 5321 of the second imaging unit 532 is located in a second spatial orientation to scan the scanned object 510 from the second spatial direction, and the fourth ray source 5341 of the fourth imaging unit 534 is located in a fourth spatial orientation to scan the scanned object 510 from the fourth spatial direction.

[0125] Specifically, during the movement of the scanned object along the first straight scanning trajectory, the linear CT imaging system 500 can call the first imaging unit 531 and the third imaging unit 533 to perform bidirectional scanning of the scanned object 510; in the second stage of the movement of the scanned object 510 along the second straight scanning trajectory, the linear CT imaging system 500 can call the second imaging unit 532 and the fourth imaging unit 534 to perform another set of bidirectional scanning of the scanned object 510. Since the first and second straight scanning trajectories are perpendicular to each other, and the first, second, third, and fourth spatial directions are different from each other, the linear CT imaging system 500 can introduce projection sampling of different spatial orientations in two orthogonal motion directions respectively.

[0126] In some embodiments, the first straight-line scanning trajectory may extend along the second direction X, and the second straight-line scanning trajectory may extend along the third direction Z, or the first straight-line scanning trajectory may extend along the third direction Z and the second straight-line scanning trajectory may extend along the second direction X.

[0127] Continue to refer to Figure 4B In embodiments of this application, the straight-line scanning trajectory may further include a first straight-line scanning trajectory, a second straight-line scanning trajectory, a third straight-line scanning trajectory, and a fourth straight-line scanning trajectory. Specifically, the first and second straight-line scanning trajectories are perpendicular to each other, the first and third straight-line scanning trajectories are parallel to each other, and the scanning object 510 moves in opposite directions in the first and third straight-line scanning trajectories. The second and fourth straight-line scanning trajectories are parallel to each other, and the scanning object 510 moves in opposite directions in the second and fourth straight-line scanning trajectories.

[0128] According to embodiments of this application, the four straight-line scanning trajectories can form an orthogonal multi-segment trajectory layout with a reciprocating scanning relationship. This trajectory layout can be understood as the scanning object 510 performing forward and reverse scanning along two mutually perpendicular directions, thereby cooperating with imaging units in different spatial orientations at different scanning stages to obtain projection data from multiple spatial directions.

[0129] In this embodiment, the first imaging unit 531 can be configured such that, during the movement of the scanned object 510 along a first straight scanning trajectory, the first X-ray source 5311 is located in a first spatial orientation to scan the scanned object 510 from the first spatial direction; the second imaging unit 532 can be configured such that, during the movement of the scanned object 510 along a second straight scanning trajectory, the second X-ray source 5321 is located in a second spatial orientation to scan the scanned object 510 from the second spatial direction; the third imaging unit 533 can be configured such that, during the movement of the scanned object 510 along a third straight scanning trajectory, the third X-ray source 5331 is located in a third spatial orientation to scan the scanned object 510 from the third spatial direction; and the fourth imaging unit 534 can be configured such that, during the movement of the scanned object 510 along a fourth straight scanning trajectory, the fourth X-ray source 5341 is located in a fourth spatial orientation to scan the scanned object 510 from the fourth spatial direction.

[0130] In this embodiment, the third X-ray source 5331 can be formed by moving the first X-ray source 5311 located in the first spatial orientation along a predetermined trajectory to the third spatial orientation; the fourth X-ray source 5341 can be formed by moving the second X-ray source 5321 located in the second spatial orientation along a predetermined trajectory to the fourth spatial orientation. Similarly, this arrangement can form four different imaging unit states in four scanning trajectories without having to configure multiple completely independent X-ray source hardware for multiple spatial orientations, thus balancing system compactness and multi-spatial imaging capability.

[0131] In this embodiment, the movement along a predetermined trajectory can be set between two adjacent scanning stages. For example, after the scanning object 510 completes scanning along the first straight-line scanning trajectory, the corresponding X-ray source can move from the first spatial orientation to the third spatial orientation so that the corresponding scan can be performed when the scanning object 510 moves along the third straight-line scanning trajectory; similarly, after the scanning object 510 completes scanning along the second straight-line scanning trajectory, the corresponding X-ray source can move from the second spatial orientation to the fourth spatial orientation so that the corresponding scan can be performed when the scanning object 510 moves along the fourth straight-line scanning trajectory. This arrangement allows the spatial orientation adjustment process of the X-ray source to coordinate with the multi-segment trajectory scanning process, thereby forming a phased and directional scanning imaging process.

[0132] According to embodiments of this application, by arranging multiple imaging units in a non-coplanar manner in three-dimensional space around the scanned object, different imaging units correspond to different spatial imaging directions during the scanning process. Compared with existing coplanar multi-segment linear CT schemes that mainly rely on angle changes within the same imaging plane, embodiments of this application introduce sampling capabilities for individual out-of-plane directions in imaging geometry through the non-coplanar spatial layout of the imaging units, resulting in a richer distribution of projection data in spatial directions. This helps alleviate the problems of artifact enhancement, structural distortion, or insufficient local characterization caused by insufficient out-of-plane direction information in traditional linear CT.

[0133] In embodiments of this application, multiple imaging units may be located on opposite sides of the transmission device along different directions, thereby forming multiple sets of transmission imaging relationships established along different lateral directions, thus achieving multi-spatial-direction imaging from a spatial layout perspective. For example, the X-ray sources of at least two of the multiple imaging units are located on a first side relative to the transmission device along a first direction Y, and the detectors of the multiple imaging units are located on a second side relative to the transmission device along the first direction Y. The first and second sides are located on opposite sides of the transmission device along the first direction Y. The X-ray source of at least one of the multiple imaging units is located on a third side relative to the transmission device along a second direction X, and the detector of at least one of the multiple imaging units is located on a fourth side relative to the transmission device along the second direction X. As in the above embodiment, the third and fourth sides are located on opposite sides of the transmission device along the second direction X.

[0134] Figure 6A This schematically illustrates a structural diagram of a linear CT imaging system that performs scanning imaging based on a first direction Y and a second direction X, according to some exemplary embodiments of this application. Figure 6B This schematically illustrates a structural diagram of a linear CT imaging system that performs scanning imaging based on a first direction Y and a second direction X, according to some other exemplary embodiments of this application. Figure 6CThe schematic diagram illustrates the structure of a linear CT imaging system that performs scanning imaging based on a first direction Y and a second direction X, according to some exemplary embodiments of this application.

[0135] like Figure 6A As shown, the linear CT imaging system 400 may include a transport device (as described above, and will not be repeated here), a scanning object 410 mounted on the transport device, and multiple imaging units. The transport device is used to move the scanning object 410 along a predetermined linear scanning trajectory. The multiple imaging units are used to scan and image the scanning object 410 from multiple different spatial directions during the movement of the scanning object 410 along the linear scanning trajectory, so as to obtain multi-directional projection data for the target area.

[0136] like Figure 6A As shown, the multiple imaging units may include at least a first imaging unit 441, a second imaging unit 442, and a third imaging unit 443. The first imaging unit 441 and the second imaging unit 442 may be arranged relative to the transmission device along a first direction Y, and the third imaging unit 443 may be arranged relative to the transmission device 420 along a second direction X. With this arrangement, the multiple imaging units can not only form a transmission scanning relationship on opposite sides corresponding to the first direction Y, but also further form another set of transmission scanning relationships in the second direction X, which is different from the first direction Y, thereby constructing a multi-spatial-direction imaging layout.

[0137] According to the embodiments of this application, since different spatial directions have different representation capabilities of internal structures, the above-mentioned multi-directional sampling method can introduce complementary information in the imaging process, thereby reducing the dependence of the reconstruction results on a single structural orientation and improving the imaging consistency and boundary clarity of complex internal structures in different spatial directions.

[0138] Combined with reference Figures 6A-6C Along the first direction Y, the radiation sources of the first imaging units 441, 411', 411'' and the second imaging units 442, 411', 411'', namely the first radiation source 4411, 4411', 4411'' and the second radiation source 4421, 4421', 4421'', can all be located on the first side; the corresponding detectors, namely the first detector 4412, 4412', 4412'' and the second detector 4422, 4422', 4422'', can be located on the second side.

[0139] Along the second direction X, the X-ray sources 4431, 4431', and 4431'' of the third imaging units 443, 443', and 443'' can be located on the third side, and the detectors 4432, 4432', and 4432'' of the third imaging units 443, 4431', and 4431'' can be located on the fourth side, thus forming another imaging relationship between the opposite sides corresponding to the second direction X. Therefore, the third imaging units 443, 443', and 443'' can scan and image the object from a spatial direction dominated by the second direction X. Correspondingly, the first imaging units 441, 411', and 411'' and the second imaging units 442, 441', and 441'' can scan and image the object from a spatial direction dominated by the first direction Y. Since the second direction X is perpendicular to the first direction Y, the main ray directions corresponding to the third imaging units 443, 443', and 443'' are significantly different from the main ray directions corresponding to the first imaging units 441, 441', and 441'', and the second imaging units 442, 442', and 442''. This allows multiple imaging units to acquire projection data of the scanned object from two distinct scanning angles, forming a multi-spatial-direction imaging layout.

[0140] In the embodiments of this application, the X-ray beams emitted by the third X-ray sources 4431, 4431', 4431'' of the third imaging units 443, 443', 443'' can form third scanning main sectors S23, S23', S23''. Specifically, any two of the first scanning main sectors S21, S21' formed by the X-ray beams emitted by the first X-ray sources 4411, 4411', 4411'' of the first imaging units 441, 441', 441'', the second scanning main sectors S22, S22' formed by the X-ray beams emitted by the second X-ray sources 4421, 4421', 442'' of the second imaging units 442, 442', 442'', and the third scanning main sectors S23, S23', S23'' can be located in different planes.

[0141] In some embodiments, the planes containing any two of the first scanning main sectors S21, S21', the second scanning main sectors S22, S22', and the third scanning main sectors S23, S23', S23'' can intersect each other. In other words, the planes containing different scanning main sectors can form lines of intersection in space, rather than being parallel or overlapping. This allows for a richer variety of spatial angular relationships between the scanning main sectors, enabling projection acquisition of the scanned object from different directions. It should be noted that "intersecting each other" here primarily describes the geometric relationship between the planes containing the scanning main sectors; it does not limit the planes to intersecting at the same angle, nor does it limit the lines of intersection to passing through the same fixed position.

[0142] In embodiments of this application, at least one straight scanning trajectory can extend along a third direction Z. In this embodiment, the first scanning main sectors S21 and S21' corresponding to the first imaging unit can be parallel to the first plane or form a first predetermined angle with the first plane, wherein the first predetermined angle is greater than 0° and less than 90°, and the first plane is a plane formed by the intersection of the first direction and the third direction; the second scanning main sectors S22 and S22' corresponding to the second imaging unit can be parallel to the second plane or form a second predetermined angle with the second plane, wherein the second predetermined angle is greater than 0° and less than 90°, and the second plane is a plane formed by the intersection of the first direction and the second direction; the third scanning main sectors S23, S23', and S23'' corresponding to the third imaging unit can be parallel to the third plane or form a third predetermined angle with the third plane, wherein the third predetermined angle is greater than 0° and less than 90°, and the third plane is a plane formed by the intersection of the second direction and the third direction.

[0143] In some embodiments, the first predetermined angle, the second predetermined angle, and the third predetermined angle may be the same or different from each other. That is, the tilt degree of the scanning main sector corresponding to different imaging units relative to their respective reference planes can be set separately according to actual needs, and it is not required that the three be completely consistent. Thus, while maintaining the distinction between multiple scanning main sectors, the imaging flexibility of the system in different spatial directions can be further enhanced.

[0144] Combined with reference Figure 6A and Figure 6B The first X-ray sources 4411, 4411' of the first imaging units 441, 411' and the second X-ray sources 4421, 4421' of the second imaging units 442, 442' can be independently arranged and spaced apart along the second direction. Specifically, the first X-ray sources 4411, 4411' and the second X-ray sources 4421, 4421' can be independent physical X-ray sources, respectively arranged in different spatial positions and having a predetermined distance in the second direction, so that the first imaging units 441, 411' and the second imaging units 442, 442' can scan and image the scanned object 410 from mutually separated spatial orientations.

[0145] Continue to refer to Figure 6BThe first X-ray source 4411' of the first imaging unit 441' and the second X-ray source 4421' of the second imaging unit 442' can be arranged at Z-intervals along the third direction. Since the first X-ray source 4411' and the second X-ray source 4421' mainly change position along a direction parallel to the linear movement direction of the scanned object 410, their corresponding main imaging spatial directions can remain basically consistent. That is to say, the first imaging unit 441' and the second imaging unit 442' still mainly scan and image the scanned object 410 from the same dominant spatial direction, but due to the different spatial positions of the X-ray sources, their corresponding X-ray beam coverage area and fan-angle expansion position can be different.

[0146] In this embodiment, the projection data acquired by the first imaging unit 441' and the projection data acquired by the second imaging unit 442' can complement each other within the fan-angle range. Specifically, when the first ray source 4411' is located in the first spatial position, its emitted ray beam can form projection sampling of the scanned object 410 within the first fan-angle range β; when the second ray source 4421' is located in the second spatial position spaced apart along the linear motion direction, its emitted ray beam can form projection sampling of the scanned object 410 within the second fan-angle range β' while keeping the main imaging spatial direction basically unchanged. Thus, the projection data corresponding to the two imaging units can complement each other in the fan-angle expansion direction, thereby increasing the effective projection coverage range under the same dominant spatial direction.

[0147] Reference Figure 6C The ray source of the second imaging unit 442'' can also be formed by moving the first ray source 4411'' of the first imaging unit 441'' located in the first spatial orientation to the second spatial orientation along a predetermined motion trajectory. This motion trajectory can be a straight line parallel to the second direction. Thus, switching between the first and second spatial orientations can be achieved with a reduced number of hardware components.

[0148] In this embodiment, the projection data acquired by the second imaging unit 442'' can be used to supplement the projection data acquired by the first imaging unit 441'' within the cone angle range. Specifically, the projection data acquired by the first imaging unit 441'' in one spatial orientation may have problems such as insufficient cone angle coverage, insufficient angle sampling, or missing local information for some spatial areas of the scanned object 410. The second imaging unit 442'' can supplement this part of the data using projection data from different spatial orientations. For example, Figure 6CThe first cone angle range γ and the second cone angle range γ' in the diagram illustrate that the projection data acquired by the first X-ray source 4411'' of the first imaging unit 441'' and the second X-ray source 4421'' of the second imaging unit 442'' can form complementarity within the cone angle range. This improves the sampling limitation of a single imaging unit within the cone angle range and enhances the characterization capability of the target region in subsequent reconstruction or detection processing.

[0149] Furthermore, the linear scanning trajectory may include a first segment of linear scanning trajectory. The first imaging units 441, 441', and 441'' can be configured such that, during the movement of the scanned object 410 along the first segment of linear scanning trajectory, the first X-ray sources 4411, 4411', and 4411'' are located in a first spatial orientation to scan the scanned object 410 from the first spatial direction; the second imaging units 442, 442', and 442'' can be configured such that, during the movement of the scanned object 410 along the first segment of linear scanning trajectory, the second X-ray sources 4421, 4421', and 4421'' are located in a second spatial orientation to scan the scanned object 410 from the second spatial direction; and the third imaging units 443, 443', and 443'' can be configured such that, during the movement of the scanned object 410 along the first segment of linear scanning trajectory, the third X-ray sources 4431, 4431', and 4431'' are located in a third spatial orientation to scan the scanned object 410 from the third spatial direction. Therefore, under a single-segment straight-line scanning trajectory, multiple imaging units can collaboratively acquire projection data from multiple different spatial directions.

[0150] In other embodiments, the linear scanning trajectory may further include a first linear scanning trajectory and a second linear scanning trajectory, wherein the first linear scanning trajectory and the second linear scanning trajectory are parallel to each other, and the scanning object 410 moves in opposite directions in the first linear scanning trajectory and the second linear scanning trajectory. The first imaging units 441, 441', and 441'' can be configured such that, during the movement of the scanned object 410 along a first straight scanning trajectory, the first X-ray sources 4411, 4411', and 4411'' are located in a first spatial orientation to scan the scanned object 410 from the first spatial direction; the second imaging units 442, 442', and 442'' can be configured such that, during the movement of the scanned object 410 along a second straight scanning trajectory, the second X-ray sources 4421, 4421', and 4421'' are located in a second spatial orientation to scan the scanned object 410 from the second spatial direction; and the third imaging units 443, 443', and 443'' can be configured such that, during the movement of the scanned object 410 along at least one of the first and second straight scanning trajectories, the third X-ray sources 4431, 4431', and 4431'' are located in a third spatial orientation to scan the scanned object 410 from the third spatial direction. By using this parallel and reverse reciprocating scanning method, imaging relationships in different spatial directions can be introduced at different scanning stages, thereby improving the comprehensive sampling capability of the scanned object 410.

[0151] In this embodiment, the X-ray sources of the second imaging units 442, 442', and 442'' can be formed by moving the first X-ray sources 4411, 4411', and 4411'' of the first imaging units 441, 441', and 441'' located in the first spatial orientation to the second spatial orientation along a predetermined motion trajectory. Specifically, during the scanning phase corresponding to the first straight-line scanning trajectory, the X-ray source can be located in the first spatial orientation to perform the scanning tasks of the first imaging units 441, 441', and 441''; during the scanning phase corresponding to the second straight-line scanning trajectory, the X-ray source can be moved to the second spatial orientation to perform the scanning tasks of the second imaging units 442, 442', and 442''.

[0152] In some embodiments, the second imaging units 442, 442', and 442'' can also be configured such that, during the movement of the scanned object 410 along the second straight-line scanning trajectory, the X-ray sources of the second imaging units 442, 442', and 442'' move along a predetermined motion trajectory, causing the second main scanning sector to scan the scanned object 410 from multiple different spatial directions. That is, during the scanning phase corresponding to the second straight-line scanning trajectory, the X-ray sources of the second imaging units 442, 442', and 442'' can move continuously or intermittently along the predetermined motion trajectory, thereby allowing the second main scanning sector to correspond to multiple different spatial directions during the scanning process. This further increases the richness of directional sampling within a single scanning phase.

[0153] It should be noted that, Figures 6A-6C The illustration schematically shows a straight-line scan trajectory that includes either a first straight-line scan trajectory segment or a second straight-line scan trajectory segment. It is understood that, similar to... Figure 3A , Figure 3C , Figure 4A and Figure 4B In some embodiments, the number of segments and direction of the linear scanning trajectory can be adjusted according to actual scanning imaging requirements. The embodiments of this application do not limit this.

[0154] In some embodiments, the plane containing the motion trajectory may be parallel to a third plane, which is the plane formed by the intersection of the second direction X and the third direction Z (i.e., the XZ plane); or, the plane containing the motion trajectory may be parallel to a second plane, which is the plane formed by the intersection of the first direction Y and the second direction X (i.e., the XY plane); or, the plane containing the motion trajectory may be parallel to a first plane, which is the plane formed by the intersection of the first direction Y and the third direction Z (i.e., the YZ plane).

[0155] Reference Figure 6A In some embodiments, the X-ray source 4421 of the second imaging unit 422 can be mounted on an angle adjustment mechanism. The angle adjustment mechanism drives the X-ray source to rotate within a certain angle range along a preset trajectory near a predetermined center position, thereby changing the emission direction of the X-ray source. Combined with... Figure 6A It can be seen that the rotation plane and the XZ plane can be parallel. Therefore, the incident direction corresponding to the second imaging unit during the scanning process is no longer fixed, but can vary around a limited angular range, thereby acquiring projection data in multiple adjacent spatial directions.

[0156] Combined with reference Figure 6B and Figure 6CIn some embodiments, the X-ray source 4421' of the second imaging unit 422' and the X-ray source 4421'' of the second imaging unit 422'' can be mounted on a spatial motion mechanism. The spatial motion mechanism is used to drive the X-ray sources to translate and / or reciprocate and / or oscillate relative to the object under test along at least one predetermined direction within a limited travel range during the scanning process. Figure 6B It can be seen that the motion trajectory in this embodiment can be parallel to the YZ plane; combined with Figure 6C It can be seen that the motion trajectory of this embodiment can be parallel to the XY plane.

[0157] In some embodiments, the motion trajectory may include at least one of a circular trajectory, an arc trajectory, or a straight trajectory. For example, the X-ray source may move between two spatial orientations along a straight trajectory to achieve a relatively simple orientation switching; it may also move along an arc trajectory or a circular trajectory to form continuously changing spatial orientation sampling during the motion. It should be understood that the specific shape of the motion trajectory can be selected according to the system structure, installation space, target area location, and scanning requirements, and the embodiments of this application do not limit this.

[0158] By driving the X-ray source to rotate, oscillate, translate, or reciprocate relative to the scanned object within a limited angular or travel range, a single imaging unit can correspond to the projected geometric relationships of multiple adjacent spatial directions during the scanning process. This method can supplement the projection sampling in specific spatial directions without significantly increasing the number of X-ray sources or introducing large-scale rotation mechanisms, thereby further enhancing the system's imaging capabilities for long-sized scanned objects, layered structures, or objects with significant anisotropy.

[0159] In some embodiments, the linear CT imaging system may further include an imaging device. The imaging device can be communicatively connected to the plurality of imaging units to receive projection data acquired by scanning the object through the plurality of spatial directions, and to jointly process the projection data to generate multi-spatial-direction tomographic images. Specifically, the imaging device can register, correct, fuse, and reconstruct projection data from multiple spatial directions to obtain tomographic images of the internal structure of the scanned object. Compared to reconstruction based solely on projection data from a single spatial direction, jointly utilizing projection data acquired from multiple spatial directions can improve the structural characterization of the target region within the scanned object, mitigate artifacts or information loss caused by finite-angle sampling, and enhance the identification of structures with different spatial orientations, defect structures, or material distribution characteristics. It should be understood that the imaging device can be implemented using hardware circuits, processor-executed program instructions, dedicated reconstruction modules, or combinations thereof; this application embodiment does not limit this.

[0160] In some embodiments, to avoid the problems of high manufacturing cost, large system size and insufficient layout flexibility caused by using large-angle X-ray sources or large-size detectors, the embodiments of this application can also adopt a combination of imaging units with multiple light sources and multiple detectors. The number, arrangement and combination of light sources can be flexibly configured according to the size range of the scanned object, the location distribution of the target detection area, the imaging resolution requirements and the system installation space. The embodiments of this application do not limit this.

[0161] It should be noted that the technical features described in the above embodiments are not limited to being used alone in their respective independent implementations. In the absence of contradictions or conflicts, the technical features in different embodiments can be arbitrarily combined or replaced to form new implementations. This application does not limit this.

[0162] Figure 7 A flowchart illustrating a scanning imaging method according to some exemplary embodiments of this application is shown. In embodiments of this application, based on the linear CT imaging system with multi-spatial-direction imaging capabilities provided above, a scanning imaging method for this system is also provided. This method includes steps S710-S730.

[0163] When operating the S710, control the scanning object to move along a straight scanning trajectory.

[0164] Understandably, the scanned object can move relative to multiple imaging units along a predetermined straight scanning trajectory under the drive of the conveying device. This straight scanning trajectory can be a single straight scanning trajectory, or it can be multiple straight scanning trajectories that are parallel, perpendicular, or parallel and opposite to each other.

[0165] During operation of S720, as the scanned object moves along a straight scanning trajectory, multiple imaging units are controlled to scan the scanned object from multiple spatial directions to obtain projection data corresponding to the multiple spatial directions.

[0166] Understandably, at least two of the multiple imaging units can be located at different spatial orientations relative to the linear scanning trajectory, and perform time-division or simultaneous transmission scanning of the scanned object from mutually distinct spatial directions. Thus, projection data from multiple spatial directions can be acquired as the scanned object moves along the linear scanning trajectory.

[0167] In operation S730, a multi-spatial-direction tomographic image of at least one target detection region in the scanned object is generated based on projection data corresponding to multiple spatial directions.

[0168] Understandably, projection data corresponding to multiple spatial directions can be jointly processed to obtain a tomographic image of the target detection region. This joint processing may include at least one of data registration, geometric correction, data fusion, and image reconstruction. By jointly utilizing projection data acquired from multiple spatial directions, the structural characterization capability of the target detection region can be improved, mitigating the finite-angle artifacts, information loss, or local occlusion problems that may arise from scanning in a single spatial direction. This, in turn, helps to improve the accuracy of subsequent detection, recognition, analysis, or judgment.

[0169] It should be noted that the numbering of each step in the above method is not a restriction on the order of the method. In the absence of conflict, the steps in the method can be executed in parallel or in a different order than that described in this application.

[0170] Figure 8 A block diagram of an electronic device suitable for implementing the methods described above, according to an embodiment of this application, is illustrated schematically. Figure 8 The illustrated electronic device is merely an example and should not be construed as limiting the functionality or scope of the embodiments of this application. For instance, in embodiments of this application, an imaging device may be implemented as the electronic device described. Furthermore, the imaging device may also be implemented as... Figure 8 The illustrated electronic device is in the form of a display screen. The embodiments of this application do not impose any particular limitation on the specific implementation of the imaging device.

[0171] like Figure 8 As shown, an electronic device 800 according to an embodiment of this application includes a processor 801, which can perform various appropriate actions and processes according to a program stored in a read-only memory 802 or a program loaded from a storage portion 808 into a random access memory 803. The processor 801 may include, for example, a general-purpose microprocessor, an instruction set processor and / or an associated chipset and / or a dedicated microprocessor. The processor 801 may also include onboard memory for caching purposes. The processor 801 may include a single processing unit or multiple processing units for executing different steps of the method flow according to an embodiment of this application.

[0172] Random access memory 803 stores various programs and data required for the operation of electronic device 800. Processor 801, read-only memory 802, and random access memory 803 are interconnected via bus 804. Processor 801 executes various steps of the method flow according to embodiments of this application by executing programs stored in read-only memory 802 and / or random access memory 803. It should be noted that the programs may also be stored in one or more memories other than read-only memory 802 and random access memory 803. Processor 801 may also execute various steps of the method flow according to embodiments of this application by executing programs stored in said one or more memories.

[0173] According to embodiments of this application, the electronic device 800 may further include an input / output interface 805, which is also connected to a bus 804. The electronic device 800 may also include one or more of the following components connected to the input / output interface 805: an input section 806 including a keyboard, mouse, etc.; an output section 807 including a cathode ray tube, liquid crystal display, etc., and a speaker, etc.; a storage section 808 including a hard disk, etc.; and a communication section 809 including a model interface card such as a local area network card, modem, etc. The communication section 809 performs communication processing via a model such as the Internet. A driver 810 is also connected to the input / output interface 805 as needed. A removable medium 811, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on the driver 810 as needed so that computer programs read from it can be installed into the storage section 808 as needed.

[0174] Embodiments of this application also provide a computer-readable storage medium, which may be included in the device / apparatus / system described in the above embodiments; or it may exist independently and not assembled into the device / apparatus / system. The computer-readable storage medium carries one or more programs, which, when executed, implement the method according to the embodiments of this application.

[0175] According to embodiments of this application, the computer-readable storage medium can be a non-volatile computer-readable storage medium, such as including but not limited to: portable computer disks, hard disks, random access memory, read-only memory, erasable programmable read-only memory, portable compact disk read-only memory, optical storage devices, magnetic storage devices, or any suitable combination thereof. In embodiments of this application, the computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. For example, according to embodiments of this application, the computer-readable storage medium may include the read-only memory 802 described above, and / or random access memory 803, and / or one or more memories other than read-only memory 802 and random access memory 803.

[0176] Embodiments of this application also include a computer program product comprising a computer program containing program code for performing the methods shown in the flowchart. When the computer program product is run on a computer system, the program code is used to cause the computer system to implement the methods provided in the embodiments of this application.

[0177] In one embodiment, the computer program may rely on a tangible storage medium such as an optical storage device or a magnetic storage device. In another embodiment, the computer program may also be transmitted and distributed as signals on a model medium, and downloaded and installed via the communication section 809, and / or installed from a removable medium 88. The program code contained in the computer program can be transmitted using any suitable model medium, including but not limited to: wireless, wired, etc., or any suitable combination thereof.

[0178] In embodiments of this application, the computer program can be downloaded and installed from the model via communication section 809, and / or installed from removable medium 811. When the computer program is executed by processor 801, it performs the functions defined in the system of embodiments of this application. According to embodiments of this application, the systems, devices, apparatuses, modules, units, etc., described above can be implemented by computer program modules.

[0179] The embodiments of this application have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of this application. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Without departing from the scope of this application, those skilled in the art can make various substitutions and modifications, all of which should fall within the scope of this application.

Claims

1. A linear CT imaging system with multi-spatial direction imaging capability, characterized in that, The system includes: A conveying device for moving the object being scanned along a predetermined straight scanning trajectory; Multiple imaging units, each including at least one radiation source and at least one detector, wherein the radiation source emits a radiation beam and the detector detects the radiation beam emitted by the radiation source and passing through the scanned object. The plurality of imaging units include a first imaging unit and a second imaging unit. The ray source of the first imaging unit is located at a first spatial orientation relative to the straight scanning trajectory to scan the object from the first spatial direction. The ray source of the second imaging unit is located at a second spatial orientation relative to the straight scanning trajectory to scan the object from the second spatial direction. The first spatial direction is different from the second spatial direction. The X-ray beam emitted by the X-ray source of the first imaging unit forms a first scanning main sector, and the X-ray beam emitted by the X-ray source of the second imaging unit forms a second scanning main sector. The first scanning main sector and the second scanning main sector are located in different planes.

2. The system according to claim 1, characterized in that, The plane containing the first scanning main sector intersects with the plane containing the second scanning main sector.

3. The system according to claim 2, characterized in that, The angle between the plane containing the first scanning main sector and the plane containing the second scanning main sector is greater than 0° and less than 90°.

4. The system according to any one of claims 1-3, characterized in that, The plurality of imaging units includes at least two imaging units that are independently configured with each other.

5. The system according to any one of claims 1-3, characterized in that, At least some of the imaging units are formed by the same imaging unit undergoing spatial orientation transformation during the scanning process.

6. The system according to claim 4, characterized in that, The first imaging unit includes a first X-ray source, and the second imaging unit includes a second X-ray source. The first X-ray source and the second X-ray source are independently arranged and distributed at intervals along a predetermined spatial trajectory.

7. The system according to claim 5, characterized in that, The X-ray source of the first imaging unit and the X-ray source of the second imaging unit are formed by the same X-ray source moving along a predetermined motion trajectory to a first spatial orientation relative to the straight scanning trajectory and to a second spatial orientation relative to the straight scanning trajectory, respectively.

8. The system according to claim 6 or 7, characterized in that, The X-ray sources of the plurality of imaging units are all located on a first side relative to the transmission device along a first direction, and the detectors of the plurality of imaging units are located on a second side relative to the transmission device along the first direction. The first side and the second side are opposite sides of the transmission device along the first direction.

9. The system according to claim 6 or 7, characterized in that, The X-ray sources of at least two of the plurality of imaging units are located on a first side relative to the transmission device along a first direction, and the detectors of the plurality of imaging units are located on a second side relative to the transmission device along the first direction, wherein the first side and the second side are opposite sides of the transmission device along the first direction. The X-ray source of at least one of the plurality of imaging units is located on a third side relative to the transmission device along a second direction, and the detector of at least one of the plurality of imaging units is located on a fourth side relative to the transmission device along a second direction, wherein the third side and the fourth side are opposite sides of the transmission device along the second direction, and the second direction is perpendicular to the first direction.

10. The system according to claim 8 or 9, characterized in that, The linear scanning trajectory includes a first segment of linear scanning trajectory; the first ray source and the second ray source are configured such that, during the movement of the scanned object along the first segment of linear scanning trajectory, the first ray source and the second ray source respectively emit ray beams to scan the scanned object.

11. The system according to claim 10, characterized in that, The straight-line scanning trajectory includes a first straight-line scanning trajectory and a second straight-line scanning trajectory. The first straight-line scanning trajectory and the second straight-line scanning trajectory are parallel to each other, and the scanning object moves in opposite directions in the first straight-line scanning trajectory and the second straight-line scanning trajectory. The first imaging unit is configured such that, during the movement of the scanned object along the first straight scanning trajectory, the ray source of the first imaging unit is located in a first spatial orientation to scan the scanned object from the first spatial direction; the second imaging unit is configured such that, during the movement of the scanned object along the second straight scanning trajectory, the ray source of the second imaging unit is located in a second spatial orientation to scan the scanned object from the second spatial direction.

12. The system according to claim 11, characterized in that, The plurality of imaging units further includes a third imaging unit and a fourth imaging unit. The X-ray source of the third imaging unit is located in a third spatial orientation relative to the straight scanning trajectory to scan the object from the third spatial direction. The X-ray source of the fourth imaging unit is located in a fourth spatial orientation relative to the straight scanning trajectory to scan the object from the fourth spatial direction. Any two of the first spatial direction, the second spatial direction, the third spatial direction, and the fourth spatial direction are different from each other.

13. The system according to claim 12, characterized in that, The X-ray beam emitted by the X-ray source of the third imaging unit forms a third scanning main sector, and the X-ray beam emitted by the X-ray source of the fourth imaging unit forms a fourth scanning main sector. Any two of the first scanning main sector, the second scanning main sector, the third scanning main sector, and the fourth scanning main sector are located in different planes.

14. The system according to claim 13, characterized in that, The planes containing any two of the first scanning main sector, the second scanning main sector, the third scanning main sector, and the fourth scanning main sector intersect each other.

15. The system according to claim 13 or 14, characterized in that, The projections of the first and third scanning main sectors onto the plane containing the detector's detection surface are parallel to each other; and / or, The projections of the second and fourth scanning main sectors onto the plane containing the detector's detection surface are parallel to each other; and / or, The projections of the first scanning main sector and the second scanning main sector onto the plane containing the detector's detection surface are perpendicular to each other; and / or, The projections of the third and fourth scanning main sectors onto the plane containing the detector's detection surface are perpendicular to each other.

16. The system according to claim 15, characterized in that, The straight-line scanning trajectory includes a first straight-line scanning trajectory and a second straight-line scanning trajectory, and the first straight-line scanning trajectory and the second straight-line scanning trajectory are perpendicular to each other; The first imaging unit and the third imaging unit are configured such that, during the movement of the scanned object along the first straight scanning trajectory, the ray source of the first imaging unit is located in a first spatial orientation to scan the scanned object from the first spatial direction, and the ray source of the third imaging unit is located in a third spatial orientation to scan the scanned object from the third spatial direction; the second imaging unit and the fourth imaging unit are configured such that, during the movement of the scanned object along the second straight scanning trajectory, the ray source of the second imaging unit is located in a second spatial orientation to scan the scanned object from the second spatial direction, and the ray source of the fourth imaging unit is located in a fourth spatial orientation to scan the scanned object from the fourth spatial direction.

17. The system according to claim 15, characterized in that, The linear scanning trajectory includes a first linear scanning trajectory, a second linear scanning trajectory, a third linear scanning trajectory, and a fourth linear scanning trajectory. The first and second linear scanning trajectories are perpendicular to each other, and the first and third linear scanning trajectories are parallel to each other. The scanning object moves in opposite directions in the first and third linear scanning trajectories. The second and fourth linear scanning trajectories are parallel to each other, and the scanning object moves in opposite directions in the second and fourth linear scanning trajectories. The first imaging unit is configured such that, during the movement of the scanned object along the first straight scanning trajectory, the ray source of the first imaging unit is located in a first spatial orientation to scan the scanned object from the first spatial direction; the second imaging unit is configured such that, during the movement of the scanned object along the second straight scanning trajectory, the ray source of the second imaging unit is located in a second spatial orientation to scan the scanned object from the second spatial direction; the third imaging unit is configured such that, during the movement of the scanned object along the third straight scanning trajectory, the ray source of the third imaging unit is located in a third spatial orientation to scan the scanned object from the third spatial direction; and the fourth imaging unit is configured such that, during the movement of the scanned object along the fourth straight scanning trajectory, the ray source of the fourth imaging unit is located in a fourth spatial orientation to scan the scanned object from the fourth spatial direction.

18. The system according to claim 11, characterized in that, The X-ray sources of the first and second imaging units in the plurality of imaging units are both located on a first side relative to the transmission device along a first direction, and the detectors of the plurality of imaging units are located on a second side relative to the transmission device along the first direction. The first side and the second side are opposite sides of the transmission device along the first direction. The plurality of imaging units further includes a third imaging unit, wherein the X-ray source of the third imaging unit is located on a third side relative to the transmission device along the second direction, and the detector of at least one of the plurality of imaging units is located on a fourth side relative to the transmission device along the second direction, wherein the third side and the fourth side are opposite sides of the transmission device along the second direction, and the second direction is perpendicular to the first direction. The third imaging unit scans the object from a spatial direction dominated by the second direction, while the first imaging unit and the second imaging unit scan the object from a spatial direction dominated by the first direction.

19. The system according to claim 18, characterized in that, The X-ray beam emitted by the X-ray source of the third imaging unit forms a third scanning main sector, and any two of the first scanning main sector, the second scanning main sector, and the third scanning main sector are located in different planes.

20. The system according to claim 19, characterized in that, The planes containing any two of the first scanning main sector, the second scanning main sector, and the third scanning main sector intersect each other.

21. The system according to any one of claims 18-20, characterized in that, At least one segment of the said straight scanning trajectory extends along a third direction, and any two of the first direction, the second direction, and the third direction are perpendicular to each other; The first scanning main sector is parallel to the first plane, or forms a first predetermined angle with the first plane, wherein the first predetermined angle is greater than 0° and less than 90°, and the first plane is a plane formed by the intersection of a first direction and a third direction; and / or, The second scanning main sector is parallel to the second plane, or forms a second predetermined angle with the second plane, wherein the first predetermined angle is greater than 0° and less than 90°, and the second plane is the plane formed by the intersection of the first direction and the second direction; and / or, The third scanning main sector is parallel to the third plane, or forms a third predetermined angle with the third plane, wherein the third predetermined angle is greater than 0° and less than 90°, and the third plane is a plane formed by the intersection of the second direction and the third direction.

22. The system according to claim 21, characterized in that, The X-ray sources of the first imaging unit and the second imaging unit are independently arranged and spaced apart along the second direction; or, The ray source of the second imaging unit is formed by moving the ray source of the first imaging unit located in the first spatial orientation along a predetermined motion trajectory to the second spatial orientation, wherein the motion trajectory is a straight line trajectory parallel to the second direction.

23. The system according to claim 22, characterized in that, The projection data acquired by the second imaging unit is used to supplement the projection data acquired by the first imaging unit within the cone angle range.

24. The system according to claim 22, characterized in that, The straight-line scanning trajectory includes a first straight-line scanning trajectory; The first imaging unit is configured such that, during the movement of the scanned object along the first straight scanning trajectory, the ray source of the first imaging unit is located in a first spatial orientation to scan the scanned object from the first spatial direction; the second imaging unit is configured such that, during the movement of the scanned object along the first straight scanning trajectory, the ray source of the second imaging unit is located in a second spatial orientation to scan the scanned object from the second spatial direction; and the third imaging unit is configured such that, during the movement of the scanned object along the first straight scanning trajectory, the ray source of the third imaging unit is located in a third spatial orientation to scan the scanned object from the third spatial direction.

25. The system according to claim 22, characterized in that, The straight-line scanning trajectory includes a first straight-line scanning trajectory and a second straight-line scanning trajectory. The first straight-line scanning trajectory and the second straight-line scanning trajectory are parallel to each other, and the scanning object moves in opposite directions in the first straight-line scanning trajectory and the second straight-line scanning trajectory. The first imaging unit is configured such that, during the movement of the scanned object along the first straight scanning trajectory, the ray source of the first imaging unit is located in a first spatial orientation to scan the scanned object from the first spatial direction; the second imaging unit is configured such that, during the movement of the scanned object along the second straight scanning trajectory, the ray source of the second imaging unit is located in a second spatial orientation to scan the scanned object from the second spatial direction; and the third imaging unit is configured such that, during the movement of the scanned object along at least one of the first straight scanning trajectory and the second straight scanning trajectory, the ray source of the third imaging unit is located in a third spatial orientation to scan the scanned object from the third spatial direction.

26. The system according to claim 25, characterized in that, The ray source of the second imaging unit is formed by moving the ray source of the first imaging unit located in the first spatial orientation along a predetermined motion trajectory to the second spatial orientation.

27. The system according to any one of claims 18-20 and 22-26, characterized in that, The second imaging unit is configured such that, during the movement of the scanned object along the second straight scanning trajectory, the ray source of the second imaging unit moves along a predetermined motion trajectory, so that the second scanning main sector scans the scanned object from multiple different spatial directions.

28. The system according to claim 27, characterized in that, The plane containing the motion trajectory is parallel to a third plane, which is the plane formed by the intersection of the second direction and the third direction; or The plane containing the motion trajectory is parallel to the second plane, which is the plane formed by the intersection of the first direction and the second direction; or The plane containing the motion trajectory is parallel to the first plane, which is the plane formed by the intersection of the first direction and the third direction.

29. The system according to claim 28, characterized in that, The motion trajectory includes at least one of a circular trajectory, an arc trajectory, or a straight trajectory.

30. The system according to any one of claims 1-3, 6-7, 11-14, 16-20, 22-26, and 28-19, characterized in that, The system also includes an imaging device configured to generate multi-spatial-direction tomographic images by jointly utilizing projection data obtained by scanning the scanned object through the multiple spatial directions.

31. A scanning imaging method using the system according to any one of claims 1-30, characterized in that, The method includes: Control the scanning object to move along a straight scanning trajectory; During the movement of the scanned object along a straight scanning trajectory, the multiple imaging units are controlled to scan the scanned object from multiple spatial directions to obtain projection data corresponding to the multiple spatial directions; Based on the projection data corresponding to the plurality of spatial directions, a multi-spatial-direction tomographic image of at least one target detection region in the scanned object is generated.

Images