CT scanning imaging system and method based on single linear scanning channel

Abstract

The present disclosure provides a CT scanning imaging system based on a single linear scanning channel. The system comprises: a conveying apparatus, used for moving a subject to be scanned along a predetermined conveying direction in the single linear scanning channel; a plurality of scanning sections, each scanning section comprising a plurality of ray sources and at least one detector, the plurality of scanning sections being arranged at intervals in the conveying direction, wherein in each scanning section, the plurality of ray sources are used for alternately emitting ray beams so as to form a scanning region, the plurality of ray sources are located on one side of the scanning channel and sequentially arranged at intervals, and the at least one detector is located on the other side of the scanning channel and used for detecting projection data formed by the ray beams after passing through the subject to be scanned while the subject to be scanned traverses the scanning region; and an imaging apparatus, which, on the basis of the projection data detected by the detectors in the plurality of scanning sections, generates a three-dimensional reconstructed image of the subject to be scanned.

Description

CT scanning imaging system and method based on single linear scanning channel

[0001] This application claims priority to Chinese patent application No. 202311490089.X filed on November 9, 2023, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present disclosure relates to the field of radiation imaging, and in particular to a CT scanning imaging system and method based on a single linear scanning channel. Background Art

[0003] Currently, related linear CT scanning systems can be divided into two categories: one is that the object under test is scanned through a single linear channel to obtain a DR image, and then an independent two-dimensional CT scan is performed at the section of interest in the channel direction to obtain detailed information inside the section; the other is that the object under test is scanned through multiple linear channels, and the angle of the object relative to the channel direction in each section is different. This can be achieved by rotating the object and fixing the channel, or by changing the direction of the fixed channel.

[0004] However, based on the current application situation, the above two technologies have at least the following related problems.

[0005] The first type of linear CT scanning system is a superposition of linear DR scanning and two-dimensional tomographic CT scanning systems, and the two systems are independent of each other: first, the DR scan is completed, and then several sections of interest are selected according to the DR image for two-dimensional tomographic CT scanning. The two scanning processes are zero-coupled, the overall process is cumbersome, and the pass rate is low; the two-dimensional tomographic CT adopts the traditional source-probe rotation scanning method, which requires a rotating track and a rack to load the source probe, and the structure is complex; an accelerator radiation source is required for imaging large cargo or vehicles, which requires higher strength of the mechanical structure and further increases the hardware cost; the DR image and the two-dimensional CT images of several sections contain less information, which is prone to false alarms and missed alarms.

[0006] In the second type of linear CT scanning system, the source and probe are fixed during the scanning process, and the ray optical path of each linear channel scanning is the same, but the projection angle of the object collected by each segment is different: if a multi-segment linear scanning method is used to reuse a single linear channel, a rotation mechanism needs to be added at one end of the channel track to rotate the inspected object between segments. The increased non-scanning time will reduce the pass rate; when scanning large cargo or vehicles, higher requirements are placed on the accuracy, strength and installation space of the rotation mechanism, further increasing the hardware cost; if the object is scanned through multiple linear channels of different angles without rotation, each scan requires a set of independent linear channels and source probes, and the cost increases with the number of segments; due to the different directions of the multiple channels, the constraint on the system installation space changes from one-dimensional for a single channel to two-dimensional; adjacent linear channels involve the handover of the inspected objects, increasing the structural complexity.

[0007] The above information disclosed in this section is only for understanding of the background of the disclosed concept of the present disclosure and therefore the above information may contain information that does not constitute the relevant art.

[0008] Summary of the Invention

[0009] The present disclosure provides a CT scanning imaging system and method based on a single linear scanning channel.

[0010] According to a first aspect of the present disclosure, a CT scanning imaging system based on a single linear scanning channel is provided, wherein the system includes: a conveying device for moving a scanned object along a predetermined conveying direction in the single linear scanning channel, wherein the conveying device includes a conveying surface on which the scanned object u is placed; p scanning segments, each scanning segment including multiple ray sources and at least one detector, the p scanning segments being arranged at intervals along the conveying direction, wherein p is a positive integer greater than or equal to 2, and in each scanning segment, multiple ray sources are used to alternately emit ray beams to form a scanning area, the multiple ray sources are located on one side of the scanning channel and are arranged in sequence at intervals; at least one detector is located on the other side of the scanning channel, and is used to detect projection data formed after the ray beam passes through the scanned object during the process of the scanned object passing through the scanning area; and an imaging device for generating a three-dimensional reconstructed image of the scanned object based on the projection data detected by each detector in the p scanning segments.

[0011] According to an embodiment of the present disclosure, the p scanning segments include the i-th scanning segment and the j-th scanning segment, wherein i and j are both positive integers greater than or equal to 1 and less than or equal to p, and i and j are not equal; the i-th scanning segment includes mi ray sources and ni detectors, mi is a positive integer greater than or equal to 2, and ni is a positive integer greater than or equal to 1; the j-th scanning segment includes mj ray sources and nj detectors, mj is a positive integer greater than or equal to 2, and nj is a positive integer greater than or equal to 1; and when observed along the scanning channel, the mi ray sources and ni detectors are arranged on both sides of the scanning channel along a first arrangement direction, and the mj ray sources and nj detectors are arranged on both sides of the scanning channel along a second arrangement direction.

[0012] According to an embodiment of the present disclosure, the first arrangement direction and the second arrangement direction are different.

[0013] According to an embodiment of the present disclosure, orthographic projections of the first arrangement direction and the second arrangement direction in a plane perpendicular to the conveying direction intersect.

[0014] According to an embodiment of the present disclosure, orthographic projections of the first arrangement direction and the second arrangement direction in a plane perpendicular to the conveying direction are perpendicular.

[0015] According to an embodiment of the present disclosure, the first arrangement direction is parallel to a width direction of the scanning channel, and the first arrangement direction is parallel to the conveying surface.

[0016] According to an embodiment of the present disclosure, the second arrangement direction is parallel to a height direction of the inspection object, and the second arrangement direction is perpendicular to the conveying surface.

[0017] According to an embodiment of the present disclosure, the first arrangement direction forms a first inclination angle with the conveying surface, and the first inclination angle is greater than 0° and less than 90°; and / or the second arrangement direction forms a second inclination angle with the conveying surface, and the second inclination angle is greater than 0° and less than 90°.

[0018] According to an embodiment of the present disclosure, orthographic projections of the first arrangement direction and the second arrangement direction in a plane perpendicular to the conveying direction coincide with each other.

[0019] According to an embodiment of the present disclosure, a first relative position of the mi ray sources relative to the ni detectors in the transmission direction is different from a second relative position of the mj ray sources relative to the nj detectors in the transmission direction.

[0020] According to an embodiment of the present disclosure, the ni detectors include a first row of detector modules arranged at the front in the transmission direction, and the nj detectors include a first row of detector modules arranged at the front in the transmission direction; and when observed in a direction perpendicular to the transmission surface, the mi ray sources are at a first offset distance relative to the first row of detector modules of the ni detectors in the transmission direction, and the mj ray sources are at a second offset distance relative to the first row of detector modules of the nj detectors in the transmission direction, and the first offset distance is not equal to the second offset distance.

[0021] According to an embodiment of the present disclosure, ni=1, ni detectors are area array detectors; and / or nj=1, nj detectors are area array detectors.

[0022] According to an embodiment of the present disclosure, ni is greater than or equal to 2, and the ni detectors are respectively linear detector columns; and / or nj is greater than or equal to 2, and the nj detectors are respectively linear detector arrays.

[0023] According to an embodiment of the present disclosure, ni detectors are arranged at intervals along the transmission direction, and / or nj detectors are arranged at intervals along the transmission direction.

[0024] According to an embodiment of the present disclosure, ni detectors are arranged at equal intervals along the transmission direction, or ni detectors are arranged at equal angular intervals along the transmission direction; and / or nj detectors are arranged at equal intervals along the transmission direction, or nj detectors are arranged at equal angular intervals along the transmission direction.

[0025] According to an embodiment of the present disclosure, a first surface angle is formed between the detection surfaces of ni detectors and the transmission surface, and a second surface angle is formed between the detection surfaces of nj detectors and the transmission surface, and the first surface angle is not equal to the second surface angle.

[0026] According to an embodiment of the present disclosure, the first face angle is approximately 90°, and the second face angle is approximately 0°.

[0027] According to an embodiment of the present disclosure, a first surface angle is formed between the detection surfaces of ni detectors and the transmission surface, a second surface angle is formed between the detection surfaces of nj detectors and the transmission surface, and the first surface angle is equal to the second surface angle.

[0028] According to an embodiment of the present disclosure, mi ray sources are arranged in sequence along a first straight line, the first straight line is an imaginary straight line extending along a first direction, and the first direction is perpendicular to the transmission surface; and / or mj ray sources are arranged in sequence along a second straight line, the second straight line is an imaginary straight line extending along a second direction, and the second direction is perpendicular to both the first direction and the transmission direction.

[0029] According to an embodiment of the present disclosure, the beam-emitting directions of the mi ray sources are all the same, and / or the beam-emitting directions of the mj ray sources are all the same; or, the beam-emitting directions of at least two of the mi ray sources are different; and / or, the beam-emitting directions of at least two of the mj ray sources are different.

[0030] According to an embodiment of the present disclosure, the ray beam emitted by at least one of the mi ray sources is a cone-shaped ray beam, which includes a main beam surface in the first fan angle direction and a main beam surface in the first cone angle direction; and the ray beam emitted by at least one of the mj ray sources is a cone-shaped ray beam, which includes a main beam surface in the second fan angle direction and a main beam surface in the second cone angle direction.

[0031] According to an embodiment of the present disclosure, the main beam plane in the first fan angle direction is parallel to the main beam plane in the second fan angle direction; and / or the main beam plane in the first cone angle direction is not parallel to the main beam plane in the second cone angle direction.

[0032] According to an embodiment of the present disclosure, the main beam plane in the first fan angle direction and the main beam plane in the second fan angle direction are not parallel; and / or the main beam plane in the first cone angle direction and the main beam plane in the second cone angle direction are parallel.

[0033] According to an embodiment of the present disclosure, the main beam surface in the first fan angle direction is perpendicular to the transmission surface, and the main beam surface in the first fan angle direction is perpendicular to the transmission direction; or, the main beam surface in the first fan angle direction is perpendicular to the transmission surface, and the main beam surface in the first fan angle direction forms a first angle with respect to the transmission direction, and the first angle is greater than 90° and less than 180°; or, the main beam surface in the first fan angle direction forms a first angle with respect to the transmission surface, and the first angle is not equal to 90°, and the main beam surface in the first fan angle direction is perpendicular to the transmission direction; or, the main beam surface in the first fan angle direction forms a first angle with respect to the transmission surface, and the first angle is not equal to 90°, and the main beam surface in the first fan angle direction forms a first angle with respect to the transmission direction, and the first angle is greater than 90° and Less than 180°; and / or, the main beam surface in the second fan angle direction is perpendicular to the transmission surface, and the main beam surface in the second fan angle direction is perpendicular to the transmission direction; or, the main beam surface in the second fan angle direction is perpendicular to the transmission surface, and the main beam surface in the second fan angle direction forms a second angle with respect to the transmission direction, and the second angle is greater than 0° and less than 90°; or, the main beam surface in the second fan angle direction forms a second angle with respect to the transmission surface, and the second angle is not equal to 90°, and the main beam surface in the second fan angle direction is perpendicular to the transmission direction; or, the main beam surface in the second fan angle direction forms a second angle with respect to the transmission surface, and the second angle is not equal to 90°, and the main beam surface in the second fan angle direction forms a second angle with respect to the transmission direction, and the second angle is greater than 0° and less than 90°.

[0034] According to an embodiment of the present disclosure, the main beam surface in the first cone angle direction is parallel to the transmission surface, or the main beam surface in the first cone angle direction is perpendicular to the transmission surface, or the main beam surface in the first cone angle direction forms a third angle relative to the transmission surface, and the third angle is greater than 0° and less than 90°; and / or the main beam surface in the second cone angle direction is parallel to the transmission surface, or the main beam surface in the second cone angle direction is perpendicular to the transmission surface, or the main beam surface in the second cone angle direction forms a fourth angle relative to the transmission surface, and the fourth angle is greater than 0° and less than 90°.

[0035] According to an embodiment of the present disclosure, the main beam surface in the first fan angle direction includes a first cone angle, the first cone angle corresponds to the size of at least one detector among the ni detectors in the first arrangement direction, and the first arrangement direction is perpendicular to the first arrangement direction; and / or, the main beam surface in the second fan angle direction includes a second cone angle, the second cone angle corresponds to the size of at least one detector among the nj detectors in the first arrangement direction, and the first arrangement direction is perpendicular to the second arrangement direction; and / or, the main beam surface in the first cone angle direction includes the first fan angle, the first fan angle corresponds to the size of the ni detectors in the second arrangement direction, and the second arrangement direction is parallel to the transmission direction; and / or, the main beam surface in the second cone angle direction includes the second fan angle, the second fan angle corresponds to the size of the nj detectors in the second arrangement direction, and the second arrangement direction is parallel to the transmission direction.

[0036] According to an embodiment of the present disclosure, the scanning object includes at least one of a container, a car and a truck, and the multiple radiation sources respectively include MeV energy level accelerators; or, the scanning object includes at least one of a suitcase and a package, and the multiple radiation sources respectively include KeV energy level X-ray machines.

[0037] A second aspect of the present disclosure provides a CT scanning imaging method based on a single linear scanning channel, wherein the method includes: causing a conveying device to drive a scanned object to move along a predetermined conveying direction in the scanning channel, wherein the conveying device includes a conveying surface for placing the scanned object; controlling the scanned object to sequentially pass through p scanning areas formed by p scanning segments, wherein before the scanned object enters the scanning range of the i-th scanning segment among the p scanning segments, controlling mi radiation sources in the i-th scanning segment to alternately emit radiation beams to form a scanning area, causing the scanned object to pass through the scanning area of ​​the i-th scanning segment, and in the process of the scanned object passing through the scanning area of ​​the i-th scanning segment, controlling ni detectors in the i-th scanning segment to detect projection data formed after the radiation beam passes through the scanned object, wherein i and j are positive integers greater than or equal to 1 and less than or equal to p, mi is a positive integer greater than or equal to 2, and ni is a positive integer greater than or equal to 1; and generating a computed tomography image of the scanned object based on the multiple projection data formed by the detectors in the p scanning segments. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to better understand the present disclosure, the present disclosure will be described in detail according to the following drawings:

[0039] FIG1 schematically shows a structural diagram of a scanning imaging system provided by an embodiment of the present disclosure.

[0040] FIG2 schematically shows a side view of a scanning imaging system viewed along a conveying direction according to an embodiment of the present disclosure.

[0041] FIG3 schematically shows a top view of a scanning imaging system provided by an embodiment of the present disclosure.

[0042] FIG4 schematically shows a schematic diagram of the beam emission direction of a ray source in a scanning imaging system provided by an embodiment of the present disclosure.

[0043] FIG5 schematically shows a side view of a scanning imaging system provided by an embodiment of the present disclosure with different source-detector arrangement directions observed along the conveying direction.

[0044] FIG6 schematically shows a structural diagram of another scanning imaging system provided by an embodiment of the present disclosure.

[0045] FIG7 schematically shows a side view of another scanning imaging system viewed along the conveying direction provided by an embodiment of the present disclosure.

[0046] FIG8 schematically shows a top view of another scanning imaging system provided by an embodiment of the present disclosure.

[0047] FIG9 schematically shows a structural block diagram of a scanning imaging system provided by an embodiment of the present disclosure.

[0048] FIG10 schematically shows a schematic diagram of a trigger pulse sequence provided by an embodiment of the present disclosure.

[0049] FIG11 schematically shows a schematic diagram of another trigger pulse sequence provided by an embodiment of the present disclosure.

[0050] FIG12 schematically shows a diagram of another trigger pulse sequence provided by an embodiment of the present disclosure.

[0051] FIG13 schematically shows a flow chart of the scanning imaging method provided in an embodiment of the present disclosure.

[0052] FIG14 schematically shows a diagram of an operation in the image reconstruction method provided by an embodiment of the present disclosure.

[0053] FIG15 schematically shows a block diagram of an imaging device of a scanning imaging system provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0054] Specific embodiments of the present disclosure will be described in detail below. It should be noted that the embodiments described herein are intended to be illustrative only and are not intended to limit the present disclosure. In the following description, a large number of specific details are set forth to provide a thorough understanding of the present disclosure. However, it will be apparent to those skilled in the art that these specific details are not necessarily required to practice the present disclosure. In other examples, known structures, materials, or methods are not specifically described to avoid obscuring the present disclosure.

[0055] Throughout this specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the present disclosure. Thus, appearances of the phrases "in one embodiment," "in an embodiment," "an example," or "an example" in various places throughout this specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, or characteristics may be combined in any suitable combinations and / or subcombinations in one or more embodiments or examples. Furthermore, one of ordinary skill in the art will understand that the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0056] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise," "include," etc. used herein indicate the presence of features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0057] 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 should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0058] Computed tomography (also known as CT) imaging refers to the use of radiation to perform cross-sectional scanning of the object being examined. The analog signal received by the detector is then converted into a digital signal. The attenuation coefficient of each pixel is calculated by an electronic computer, and the image is reconstructed to display the cross-sectional structure of each part of the object being examined.

[0059] It should be noted that the scanning imaging system and method provided by the embodiments of the present disclosure are suitable for performing security inspections on items in various public places, and can obtain a distribution map of the internal attenuation coefficient of an object and automatically identify dangerous goods.

[0060] FIG1 is a schematic diagram of the structure of a scanning imaging system provided by an embodiment of the present disclosure. As shown in FIG1 , the scanning imaging system includes: a conveying device 3 , p scanning segments, a scanning channel 4 and an imaging device 5 .

[0061] In the embodiments of the present disclosure, p is a positive integer greater than or equal to 2, i.e., the scanning imaging system includes more than two scanning segments. In the embodiment shown in FIG1 , two scanning segments are exemplarily shown. For example, the p scanning segments may include the i-th scanning segment and the j-th scanning segment, where i and j are both positive integers greater than or equal to 1 and less than or equal to p, and i and j are not equal. The two scanning segments exemplarily shown in FIG1 may be the i-th scanning segment and the j-th scanning segment.

[0062] For example, the i-th scanning segment may include mi ray sources and ni detectors, where mi is a positive integer greater than or equal to 2, and ni is a positive integer greater than or equal to 1. The j-th scanning segment may include mj ray sources and nj detectors, where mj is a positive integer greater than or equal to 2, and nj is a positive integer greater than or equal to 1. Observing along the scanning channel, the mi ray sources and the ni detectors are arranged on both sides of the scanning channel along a first arrangement direction D4, and the mj ray sources and the nj detectors are arranged on both sides of the scanning channel along a second arrangement direction D5.

[0063] In the following, for the convenience of description, i=1 and j=2 are used as an example, i.e., the first and second scanning segments. It should be understood that this description is only used as an example to illustrate the embodiment of the present disclosure and is not intended to limit the embodiment of the present disclosure.

[0064] As shown in FIG1 , two scanning segments are arranged at intervals along a transmission direction D3 (indicated by the arrow in FIG1 ). The first scanning segment includes m1 radiation sources 1 and n1 detectors 2, and the second scanning segment includes m2 radiation sources 1 and n2 detectors 2. For example, m1 is a positive integer greater than or equal to 2, n1 is a positive integer greater than or equal to 1, m2 is a positive integer greater than or equal to 2, and n2 is a positive integer greater than or equal to 1.

[0065] Specifically, the conveyor 3 is used to move the scanned object 30 along a predetermined conveying direction D3 in the scanning channel 4. The conveyor 3 includes a conveying surface 3S on which the scanned object 30 is placed. For example, the conveyor 3 can be implemented as a belt conveyor, a chain conveyor, a gear conveyor, or other transmission method, which is not limited herein. For example, the scanned object 30 is placed on the conveying surface 3S of the conveyor 3.

[0066] In the embodiment of FIG. 1 , the scanning channel 4 is a single linear scanning channel 4 , that is, the motion trajectory of the scanning object 30 moving along a single predetermined transmission direction D3 in the scanning area is a linear trajectory.

[0067] Continuing with Figure 1 , in the first scanning segment, m1 radiation sources 1 and n1 detectors 2 are arranged on either side of the scanning channel 4 along a first arrangement direction D4, wherein the first arrangement direction D4 is parallel to the width of the scanning channel 4 and parallel to the transmission surface 3S. The m1 radiation sources 1 are configured to alternately emit radiation beams to form a scanning area. The m1 radiation sources 1 are located on one side of the scanning channel 4 and are sequentially spaced apart along a first straight line L1, which is an imaginary straight line extending along a first direction D1 perpendicular to the transmission surface 3S. That is, the multiple radiation sources 1 are distributed at different heights on a vertical line and alternately emit radiation beams to form a scanning area.

[0068] Referring to Figures 1 and 2, in the second scanning segment, m2 radiation sources 1 and n2 detectors 2 are arranged above and below the scanning channel 4 along a second arrangement direction D5. The second arrangement direction D5 is parallel to the height of the scanned object 30 and perpendicular to the transmission surface 3S. The m2 radiation sources 1 are configured to alternately emit radiation beams to form a scanning area. The m2 radiation sources 1 are located below the scanning channel 4 and are sequentially spaced along a second straight line L2, an imaginary straight line extending in a second direction D2 that is perpendicular to both the first direction D1 and the transmission direction D3. The multiple radiation sources 1 alternately emit radiation beams to form a scanning area.

[0069] It should be noted that the first arrangement direction D4 and the second arrangement direction D5 are different. The orthographic projections of the first arrangement direction D4 and the second arrangement direction D5 in a plane perpendicular to the conveying direction D3 intersect. The orthographic projections of the first arrangement direction D4 and the second arrangement direction D5 in a plane perpendicular to the conveying direction D3 are perpendicular.

[0070] Exemplarily, the scan object 30 includes at least one of a container, a car, and a truck, or the scan object 30 includes at least one of a suitcase and a package.

[0071] Exemplarily, the radiation source 1 may be an accelerator, for example, a MeV energy-level accelerator, the energy of which can be adjusted and which has strong penetrating power. It should be noted that the embodiments of the present disclosure do not impose any particular limitation on the type of radiation source 1. In other embodiments, the radiation source 1 may be other types of radiation sources 1, for example, a KeV energy-level X-ray machine.

[0072] Continuing with FIG1 , in the first scanning segment, n1 detectors 2 are used to detect projection data formed after the radiation beam passes through the scanning object 30 as the scanning object 30 passes through the scanning area, wherein the n1 detectors 2 are located on the other side of the scanning channel 4, and the n1 detectors 2 are arranged in sequence along the transmission direction D3.

[0073] Continuing with FIG1 , in the second scanning segment, n2 detectors 2 are used to detect projection data formed after the radiation beam passes through the scanning object 30 as the scanning object 30 passes through the scanning area, wherein the n2 detectors 2 are located on the upper side of the scanning channel 4, and the n2 detectors 2 are arranged in sequence along the transmission direction D3.

[0074] It should be noted that, in the embodiment of the present disclosure, the n1 detectors 2 and the n2 detectors 2 are linear detector arrays, for example, multiple rows of detectors or planar array detectors.

[0075] 1 , n1 detectors 21 are arranged at equal distances along the conveying direction D3 , and n2 detectors 2 are also arranged at equal distances along the conveying direction D3 .

[0076] In the embodiment of the present disclosure, the detection surfaces of the n1 detectors 21 form a first surface angle δ1 with the conveying surface 3S, and the detection surfaces of the n2 detectors 2 form a second surface angle with the conveying surface 3S. The first surface angle δ1 and the second surface angle are not equal. As shown in FIG1 , the first surface angle δ1 is approximately 90°, and the second surface angle is approximately 0°.

[0077] The imaging device 5 is used to generate a computed tomography image (ie, a CT image) of the scanned object 30 according to the projection data detected by each detector 2 in the two scanning segments.

[0078] In the scanning imaging system according to the embodiment of the present disclosure, when inspecting the scanned object 30, the conveying device 3 can move the scanned object 30 along a predetermined conveying direction D3 in the scanning channel 4 and pass through multiple scanning segments. The multiple radiation sources 1 in each scanning segment alternately emit radiation beams to form a scanning area. Then, the multiple detectors 2 in each scanning segment detect the projection data formed after the radiation beams emitted by the multiple radiation sources 1 pass through the object as it passes through the scanning segment. Then, the imaging device 5 generates a computed tomography image of the scanned object 30 based on the multiple projection data formed by the detectors 2 in the multiple scanning segments. In other words, in the scanning imaging system according to the embodiment of the present disclosure, the scan is completed and the reconstruction of the three-dimensional image is completed through a single scan, that is, the object under inspection passes through the linear channel once. There is no rotation or movement during the scanning process, the transmission device has low complexity and a high pass rate.

[0079] It should be noted that in the embodiment of the present disclosure, the conveying device 3 moves the scanning object 30 along the predetermined conveying direction D3, a single linear track, and no intersection of multiple linear tracks. The system installation space limitation is also one-dimensional, and the site requirements are low.

[0080] It should be noted that in the embodiment of the present disclosure, the positions of the multiple ray sources 1 and the multiple detectors 2 in each scanning segment are fixed, and there is no rotation or movement during the scanning process, and no rotating frame or motion track is required.

[0081] It should also be noted that in the embodiment of the present disclosure, the arrangement directions of the multiple ray sources 1 and the multiple detectors 2 of each scanning segment can be different. By quickly switching the beam out for scanning, any projection angle can be increased, and the data completeness can be improved without affecting the scanning speed.

[0082] It should also be noted that, in the embodiments of the present disclosure, as the number of scanning segments increases, the number of source-detector groups increases linearly, and the better the completeness of the projection data, the higher the quality of the reconstructed image.

[0083] In some exemplary embodiments, the ray beam emitted by at least one of the mi ray sources is a cone-shaped ray beam. For example, referring to FIG1 , each source probe group is labeled with the central cross-section of the cone beam emitted by the intermediate ray source, where the thin dashed line represents the main beam plane in the fan angle direction, and the angle within the plane is the cone angle; the thick dashed line represents the main beam plane in the cone angle direction, and the angle within the plane is the fan angle.

[0084] Figure 2 schematically shows a side view of a scanning imaging system provided by an embodiment of the present disclosure, viewed along a conveying direction. Figure 3 schematically shows a top view of a scanning imaging system provided by an embodiment of the present disclosure.

[0085] For example, referring to Figure 2 and Figure 3, in the first scanning segment, the ray beam emitted by at least one ray source 1 among the m1 ray sources 1 includes a first fan angle direction main beam surface 8 (indicated by a dotted line) and a first cone angle direction main beam surface 9 (indicated by a dotted and solid line); in the second scanning segment, the ray beam emitted by at least one ray source 1 among the m2 ray sources 1 includes a second fan angle direction main beam surface 10 (indicated by a dotted line) and a second cone angle direction main beam surface 11 (indicated by a dotted and solid line).

[0086] 2 , the main beam plane 8 in the first sector angle direction and the main beam plane 10 in the second sector angle direction are parallel.

[0087] 3 , the main beam surface 9 in the first cone angle direction and the main beam surface 11 in the second cone angle direction are not parallel.

[0088] Continuing to refer to Figures 2 and 3, the main beam plane 8 in the first fan angle direction is perpendicular to the conveying surface 3S, and the main beam plane 8 in the first fan angle direction is perpendicular to the conveying direction D3; or, the main beam plane 8 in the first fan angle direction is perpendicular to the conveying surface 3S, and the main beam plane 8 in the first fan angle direction forms a first angle with respect to the conveying direction D3, and the first angle is greater than 90° and less than 180°.

[0089] In some exemplary embodiments, the main beam surface 8 in the first fan angle direction forms a first angle with respect to the transmission surface 3S, the first angle is not equal to 90°, and the main beam surface 8 in the first fan angle direction is perpendicular to the transmission direction D3; or, the main beam surface 8 in the first fan angle direction forms a first angle with respect to the transmission surface 3S, the first angle is not equal to 90°, and the main beam surface 8 in the first fan angle direction forms a first angle with respect to the transmission direction D3, and the first angle is greater than 90° and less than 180°.

[0090] Continuing to refer to Figures 2 and 3, the main beam plane 10 in the second fan angle direction is perpendicular to the transmission surface 3S, and the main beam plane 10 in the second fan angle direction is perpendicular to the transmission direction D3; or, the main beam plane 10 in the second fan angle direction is perpendicular to the transmission surface 3S, and the main beam plane 10 in the second fan angle direction is at a second angle relative to the transmission direction D3, and the second angle is greater than 0° and less than 90°.

[0091] In some exemplary embodiments, the main beam surface 10 in the second fan angle direction forms a second angle with respect to the transmission surface 3S, the second angle is not equal to 90°, and the main beam surface 10 in the second fan angle direction is perpendicular to the transmission direction D3; or, the main beam surface 10 in the second fan angle direction forms a second angle with respect to the transmission surface 3S, the second angle is not equal to 90°, and the main beam surface 10 in the second fan angle direction forms a second angle with respect to the transmission direction D3, and the second angle is greater than 0° and less than 90°.

[0092] Continuing with FIG3 , the main beam plane 9 in the first cone angle direction is parallel to the transmission surface 3S, and the main beam plane 11 in the second cone angle direction is perpendicular to the transmission surface 3S. Alternatively, for example, the main beam plane 9 in the first cone angle direction may form a third angle with respect to the transmission surface 3S, the third angle being greater than 0° and less than 90°, or the main beam plane 11 in the second cone angle direction may form a fourth angle with respect to the transmission surface 3S, the fourth angle being greater than 0° and less than 90°.

[0093] 2, the main beam surface 8 in the first fan angle direction includes a first cone angle The first cone angle corresponds to the size of at least one detector 2 in the n1 detectors 2 in the first arrangement direction, and the first arrangement direction is perpendicular to the first arrangement direction D4. The second fan angle direction main beam plane 10 includes the second cone angle The second cone angle corresponds to the size of at least one detector 2 among the n2 detectors 2 in the first arrangement direction, and the first arrangement direction is perpendicular to the second arrangement direction D5.

[0094] Continuing with Figure 3 , the first cone-angle primary beam plane 9 includes a first fan angle θ1, which corresponds to the size of the n1 detectors 2 in the second arrangement direction, which is parallel to the transmission direction D3. The second cone-angle primary beam plane 11 includes a second fan angle θ2, which corresponds to the size of the n2 detectors 2 in the second arrangement direction, which is parallel to the transmission direction D3.

[0095] Through the embodiments of the present disclosure, it is ensured that the arrangement directions and angles of the source probes in different scanning segments are different, thereby increasing the projection angle range.

[0096] FIG4 schematically shows a schematic diagram of the beam emission direction of the ray source 1 in the scanning imaging system provided by an embodiment of the present disclosure.

[0097] In the embodiment of the present disclosure, in each scanning segment, the beam emission directions of the multiple ray sources 1 are the same, and / or the beam emission directions of the multiple ray sources 1 are different.

[0098] As shown in FIG4 , the main beam planes (three dotted lines) in the fan angle direction emitted by the three ray sources 1 are facing in different directions. At this time, the beam output directions of the multiple ray sources 1 are different. By quickly switching the beam output for scanning, the projection angle can be increased and the data completeness can be improved without affecting the scanning speed.

[0099] FIG5 schematically shows a side view of a scanning imaging system provided by an embodiment of the present disclosure with different source-detector arrangement directions observed along the conveying direction.

[0100] In an embodiment of the present disclosure, the first arrangement direction D4 forms a first inclination angle with the conveying surface 3S, and the first inclination angle is greater than 0° and less than 90°; and / or the second arrangement direction D5 forms a second inclination angle with the conveying surface 3S, and the second inclination angle is greater than 0° and less than 90°.

[0101] For example, according to different source-detector arrangement directions, another scanning imaging system is provided in an embodiment of the present disclosure. As shown in FIG6 , FIG6 schematically shows a structural diagram of another scanning imaging system provided in an embodiment of the present disclosure.

[0102] In the first scanning segment, m1 radiation sources 1 and n1 detectors 2 are arranged on either side of scanning channel 4 along a first arrangement direction D4, where first arrangement direction D4 is parallel to conveying surface 3S. The m1 radiation sources 1 are configured to alternately emit radiation beams to form a scanning area. The m1 radiation sources 1 are located on one side of scanning channel 4 and are sequentially spaced apart along a first straight line L1. The multiple radiation sources 1 alternately emit radiation beams to form a scanning area.

[0103] Continuing with FIG6 , in the second scanning segment, m2 radiation sources 1 and n2 detectors 2 are arranged on both sides of the scanning channel 4 along a second arrangement direction D5, where the second arrangement direction D5 is parallel to the conveying surface 3S. The m2 radiation sources 1 are configured to alternately emit radiation beams to form a scanning area. The m2 radiation sources 1 are located on one side of the scanning channel 4 and are sequentially spaced apart along the first straight line L2. The multiple radiation sources 1 alternately emit radiation beams to form the scanning area.

[0104] It should be noted that, the orthographic projections of the first arrangement direction D4 and the second arrangement direction D5 in a plane perpendicular to the conveying direction D3 coincide with each other.

[0105] 6 , it should be noted that, in the embodiment of the present disclosure, n1 detectors 21 are arranged at equal angular intervals along the conveying direction D3 , and n2 detectors 2 are also arranged at equal angular intervals along the conveying direction D3 .

[0106] In the embodiment of the present disclosure, a first surface angle is formed between the detection surfaces of n1 detectors 21 and the transmission surface 3S, and a second surface angle is formed between the detection surfaces of n2 detectors 2 and the transmission surface 3S. The first surface angle is equal to the second surface angle.

[0107] Through the embodiments of the present disclosure, the arrangement directions of multiple ray sources 1 and multiple detectors 2 in each scanning segment can be different. By quickly switching the beam out for scanning, any projection angle can be increased. As the scanning segments continue to increase, the number of source-detector groups increases linearly, the better the completeness of the projection data, and the higher the quality of the reconstructed image.

[0108] Figure 7 schematically shows a side view of another scanning imaging system provided by an embodiment of the present disclosure, viewed along the conveying direction. Figure 8 schematically shows a top view of another scanning imaging system provided by an embodiment of the present disclosure.

[0109] Please refer to Figures 7 and 8. In the first scanning segment, the ray beam emitted by at least one ray source 1 among the m1 ray sources 1 includes a main beam plane 8 in the first fan angle direction (represented by the dotted line) and a main beam plane 9 in the first cone angle direction (represented by the dotted and solid lines); in the second scanning segment, the ray beam emitted by at least one ray source 1 among the m2 ray sources 1 includes a main beam plane 10 in the second fan angle direction (represented by the dotted line) and a main beam plane 11 in the second cone angle direction (represented by the dotted and solid lines).

[0110] 7 , illustratively, the main beam plane 8 in the first fan angle direction and the main beam plane 10 in the second fan angle direction are not parallel.

[0111] 8 , illustratively, the main beam surface 9 in the first cone angle direction and the main beam surface 11 in the second cone angle direction are parallel.

[0112] 8 , the main beam surface 9 in the first cone angle direction is parallel to the transmission surface 3S, and the main beam surface 11 in the second cone angle direction is parallel to the transmission surface 3S.

[0113] The first relative position of the m1 radiation sources 1 relative to the n1 detectors 2 in the transmission direction D3 is different from the second relative position of the m2 radiation sources 1 relative to the n2 detectors 2 in the transmission direction D3.

[0114] Continuing with FIG8 , the n1 detectors 2 comprise a first row of detector 2 modules arranged forward in the conveying direction D3, and the n2 detectors 2 comprise a first row of detector 2 modules arranged forward in the conveying direction D3. As viewed in a direction perpendicular to the conveying surface 3S, the m1 radiation source 1 is spaced a first offset distance from the first row of detector 2 modules of the n1 detectors 2 in the conveying direction D3, and the m2 radiation source 1 is spaced a second offset distance from the first row of detector 2 modules of the n2 detectors 2 in the conveying direction D3. The first offset distance and the second offset distance are not equal.

[0115] The working process of the scanning imaging system according to the embodiment of the present disclosure is described in detail below. By way of example, the working process of the scanning imaging system may include the following steps.

[0116] First, the scanning object 30 is fixed on the conveying device 3 , and the scanning object 30 is moved in the scanning channel 4 along the conveying direction D3 of the conveying device 3 .

[0117] Next, through multiple scanning sections, multiple radiation sources 1 in each scanning section emit radiation beams alternately to form a scanning area.

[0118] Then, the multiple detectors 2 in each scanning section detect projection data formed after the ray beams emitted by the multiple ray sources 1 pass through the object during the process of the object passing through the scanning section.

[0119] Then, the imaging device 5 obtains a three-dimensional reconstructed image of the scanned object 30 based on the multiple projection data formed by the detector 2 in the multiple scanning segments.

[0120] According to an embodiment of the present disclosure, referring to Figure 9 , the scanning imaging system may further include a pulse generator 7 for generating a trigger pulse sequence for controlling the multiple ray sources 1 to alternately emit ray beams. Specifically, the pulse trigger sequence may include the following situations.

[0121] In the first case, one cycle of the trigger pulse sequence includes trigger pulse signals corresponding to a plurality of ray sources 1 one by one, and the trigger pulse signals are used to control the corresponding ray sources 1 to emit ray beams with the same energy.

[0122] For example, Figure 10 shows trigger pulse signals corresponding to three radiation sources 1. The horizontal axis indicates time, with the trigger pulse signals corresponding to the three radiation sources 1 arranged alternately along the time axis. The vertical axis indicates energy, with all trigger pulse signals indicating the energy E1. The projection image data obtained using this method is complete data that can be used for single-energy CT reconstruction.

[0123] In the second case, one cycle of the trigger pulse sequence includes a trigger pulse signal group corresponding one-to-one to multiple radiation sources 1. The trigger pulse signal group includes a first trigger pulse signal and a second trigger pulse signal. The first trigger pulse signal and the second trigger pulse signal are used to control the corresponding radiation source 1 to sequentially emit a first sub-beam of radiation having a first energy and a second sub-beam of radiation having a second energy. The radiation source 1 may be a dual-energy accelerator with adjustable energy.

[0124] For example, Figure 11 shows trigger pulse signal groups corresponding one-to-one with three radiation sources 1, meaning each radiation source 1 emits a beam twice. The horizontal axis indicates time, with the trigger pulse signal groups corresponding one-to-one with the three radiation sources 1 alternating along the time axis. The vertical axis indicates energy, with the first trigger pulse signal in each trigger pulse signal group indicating an energy of E2, and the second trigger pulse signal in each trigger pulse signal group indicating an energy of E3. The projection image data obtained in this manner is complete and can be used for dual-energy CT reconstruction.

[0125] The principle of dual-energy CT image reconstruction is described in detail below.

[0126] First, the object 30 is scanned using dual-energy rays to obtain dual-energy projection data;

[0127] The base material coefficient projection values ​​corresponding to the dual-energy projection data are then calculated using a pre-created lookup table or by solving a set of equations. The lookup table is created by selecting two base materials and calculating the projection values ​​of the dual-energy rays passing through them at different thicknesses. This lookup table is then generated based on the relationship between high- and low-energy projection values ​​and different thickness combinations. The analytical solution to the set of equations utilizes the actual high- and low-energy projection values ​​to obtain the corresponding thickness combinations by solving the high- and low-energy projection equations for the base material decomposition.

[0128] Then, the projection values ​​of the base material can be used to obtain a distribution image of the base material coefficient. From the base material coefficient distribution, the atomic number of the scanned object 30, a characteristic density image, and an attenuation coefficient image of the scanned object 30 at any energy can be obtained, thereby classifying and automatically identifying the material of the scanned object 30.

[0129] It should be noted that, in order to perform dual-energy CT reconstruction on the projection image data obtained in the second case, the scanning imaging system further includes a decomposition unit that decomposes the first and second projection data into first and second sub-projection data corresponding to the first and second sub-beams, respectively. The imaging device 5 obtains a reconstructed image of the scanned object 30 based on the first and second sub-projection data of the first projection data and the first and second sub-projection data of the second projection data.

[0130] In the third case, the radiation source 1 may be a mono-energy accelerator with adjustable energy. One cycle of the trigger pulse sequence includes trigger pulse signals corresponding to multiple radiation sources 1. During the first scan of the scanned object 30, the trigger pulse signals are used to control the corresponding radiation sources 1 to emit radiation beams having a first uniform energy. During the second scan of the scanned object 30, the trigger pulse signals are used to control the corresponding radiation sources 1 to emit radiation beams having a second uniform energy.

[0131] For example, during the first scan, all trigger pulse signals indicate an energy of E1 (see FIG10 ); during the second scan, all trigger pulse signals indicate an energy of E4 (see FIG12 ). Projection image data obtained in this manner can also be used for dual-energy CT reconstruction. The resulting image information of the scanned object 30 includes information such as high-energy attenuation coefficient, low-energy attenuation coefficient, atomic number, and electron density, thereby enabling material classification and automatic identification of the scanned object 30.

[0132] FIG13 is a flow chart of a scanning imaging method provided by an embodiment of the present disclosure, which is applied to the scanning imaging system described above. The scanning imaging method in FIG13 includes steps S131 to S134.

[0133] In step S131 , the conveying device 3 drives the scanning object 30 to move along a predetermined conveying direction D3 in the scanning channel 4 , wherein the conveying device 3 includes a conveying surface 3S for placing the scanning object 30 .

[0134] In step S132, the scanning object 30 is controlled to pass through p scanning areas formed by p scanning segments in sequence, wherein, before the scanning object 30 enters the scanning range of the i-th scanning segment among the p scanning segments, the mi radiation sources 1 in the i-th scanning segment are controlled to alternately emit radiation beams to form a scanning area, so that the scanning object 30 passes through the scanning area of ​​the i-th scanning segment, wherein i and j are positive integers greater than or equal to 1 and less than or equal to p, mi is a positive integer greater than or equal to 2, and ni is a positive integer greater than or equal to 1.

[0135] In step S133 , when the scanned object 30 passes through the scanning area of ​​the i-th scanning segment, the ni detectors 2 in the i-th scanning segment are controlled to detect projection data formed after the ray beam passes through the scanned object 30 .

[0136] In step S134 , a computed tomography image of the scanned object 30 is generated based on the plurality of projection data formed by the detector 2 in the p scanning segments.

[0137] In an embodiment of the present disclosure, a scanning imaging system is provided based on multiple scanning segments including distributed ray sources and detectors. The image reconstruction algorithm may be a reconstruction algorithm based on differential back projection filtering, which can perform reconstruction while scanning, thereby improving the efficiency of image reconstruction and reducing waiting time.

[0138] Specifically, with reference to FIG. 14 , in an embodiment of the present disclosure, the image reconstruction algorithm may be performed according to the following operations.

[0139] In operation S141, for each individual radiation source, for example, one of the mi radiation sources in the i-th scanning segment, this individual radiation source is labeled m0 for ease of description. This individual radiation source m0 and its corresponding ni detectors form a source-detector combination. This source-detector combination includes a detector array formed by the single radiation source m0 and the ni detectors. Each of the ni detectors may include K detector units. For example, in the example shown in FIG14 , the K detector units are arranged in a vertical direction.

[0140] In operation S142, the radiation source m0 and the kth detector elements in the detector array from the 1st to the nith detector elements form a plane Pk. This plane Pk can be horizontal, vertical, or inclined. As the object 30 passes through the scanning area, differential backprojection images of all ni detectors on plane Pk are obtained. A reconstructed image of plane Pk is obtained using a reconstruction algorithm.

[0141] In operation S143 , for the ray source m0 , the 1st to Kth planes can be processed according to this step to obtain reconstructed images of the 1st to Kth planes, thereby obtaining a reconstruction result obtained by scanning the ray source m0 .

[0142] In operation S144 , the reconstruction process for the ray source m0 is repeated for each ray source to obtain a set of reconstructed images from data of different ray sources.

[0143] In operation S145 , normalized weighted fusion is performed on the reconstructed images obtained for the plurality of ray source data to obtain a final reconstructed image.

[0144] In the above-mentioned operation S143, image reconstruction is performed on each plane. The operations between each plane are independent of each other, so they can be calculated in parallel. In the above-mentioned operation S144, a complete 3D CT image is reconstructed for each ray source. The operations between each ray source are also independent of each other, so they can also be calculated in parallel. Therefore, in the embodiments of the present disclosure, the above-mentioned operations can fully utilize the GPU cluster for distributed parallel computing, thereby improving the image reconstruction speed.

[0145] In some exemplary embodiments, the scanning imaging system further includes a pulse trigger. Before the step of causing multiple ray sources 1 to alternately emit ray beams to form a scanning area, the scanning imaging method further includes: the pulse trigger generates a trigger pulse sequence for controlling the multiple ray sources 1 to alternately emit ray beams.

[0146] Among them, one cycle of the trigger pulse sequence may include trigger pulse signals corresponding to multiple ray sources 1 one by one. The trigger pulse signals are used to control the corresponding ray sources 1 to emit ray beams with the same energy.

[0147] A cycle of the trigger pulse sequence may also include a trigger pulse signal group corresponding to multiple radiation sources 1. The trigger pulse signal group includes a first trigger pulse signal and a second trigger pulse signal. The first trigger pulse signal and the second trigger pulse signal are used to control the corresponding radiation source 1 to sequentially emit a first sub-beam of radiation having a first energy and a second sub-beam of radiation having a second energy. The imaging device 5 obtains a reconstructed image of the scanned object 30 based on the first sub-projection data and the second sub-projection data decomposed from the projection data.

[0148] According to the scanning imaging system and imaging method of the embodiment of the present disclosure, when conducting a security inspection on an object, the conveying device can move the object along a predetermined conveying direction; and pass through multiple scanning segments, and the multiple radiation sources in each scanning segment alternately emit radiation beams to form a scanning area, and then the multiple detectors in each scanning segment detect the projection data formed after the radiation beams emitted by the multiple radiation sources pass through the object during the process of the object passing through the scanning segment; then the imaging device generates a computerized tomography image of the scanned object based on the multiple projection data formed by the detectors in the multiple scanning segments. The scanning system has a simple structure, a single linear track, no need for a rotating frame, the object does not rotate during scanning, the source and detector remain stationary, and the scanning can be completed by passing through the channel once and with multiple sets of source and detectors quickly switching out beams, and a complete high-quality three-dimensional reconstructed image of the object being inspected is given.

[0149] FIG15 schematically shows a block diagram of an imaging device of a scanning imaging system according to an embodiment of the present disclosure.

[0150] As shown in FIG15 , the imaging device 5 of the scanning imaging system according to an embodiment of the present disclosure may include a processor 401, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 402 or a program loaded from a storage portion 408 into a random access memory (RAM) 403. The processor 401 may, for example, include a general-purpose microprocessor (e.g., a CPU), an instruction set processor and / or a related chipset and / or a dedicated microprocessor (e.g., an application-specific integrated circuit (ASIC)), etc. The processor 401 may also include an onboard memory for caching purposes. The processor 401 may include a single processing unit or multiple processing units for executing different actions of the method flow according to an embodiment of the present disclosure.

[0151] Various programs and data required for the operation of the electronic device 400 are stored in the RAM 403. The processor 401, ROM 402, and RAM 403 are connected to each other via a bus 404. The processor 401 executes the programs in the ROM 402 and / or RAM 403 to perform various operations of the method flow according to the embodiment of the present disclosure. It should be noted that the programs may also be stored in one or more memories other than the ROM 402 and RAM 403. The processor 401 may also execute the programs stored in one or more memories to perform various operations of the method flow according to the embodiment of the present disclosure.

[0152] According to an embodiment of the present disclosure, electronic device 400 may further include an input / output (I / O) interface 405, which is also connected to bus 404. Electronic device 400 may further include one or more of the following components connected to I / O interface 405: an input portion 406 including a keyboard, a mouse, etc.; an output portion 407 including devices such as a cathode ray tube (CRT), a liquid crystal display (LCD), and speakers; a storage portion 408 including a hard disk; and a communication portion 409 including a network interface card such as a LAN card or a modem. Communication portion 409 performs communication processing via a network such as the Internet. A drive 410 is also connected to I / O interface 405 as needed. Removable media 411, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed in drive 410 as needed, so that computer programs read therefrom can be installed into storage portion 408 as needed.

[0153] The flowcharts and block diagrams in the accompanying drawings illustrate the possible implementation architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, program segment, or a part of code, and the above-mentioned module, program segment, or a part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0154] In an embodiment of the present disclosure, a scanning imaging system and a corresponding scanning imaging method are provided. In this scanning imaging system, a DR system design based on linear CT is implemented, without any impact on the original scanning method of the linear CT and without adding any additional linear CT scanning steps. By simply replacing one or several rows of detectors 2, a clearer and more complete DR image can be obtained without degrading the three-dimensional reconstructed image. When the ray source 1 adopts a dual-energy beam mode, the DR image color is also more accurate. When the ray source 1 adopts a dual-energy beam mode, the second detector 2 adopts a detector 2 with energy resolution capability, thereby achieving spectral DR with more energy spectrum measurements, more accurate image color, and the classification of more substances.

[0155] The embodiments of the present disclosure are described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present disclosure. Although each embodiment has been described separately above, this does not mean that the measures in each embodiment cannot be used in combination to advantage. The scope of the present disclosure is defined by the appended claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A CT scanning imaging system based on a single linear scanning channel, wherein: The system comprises: A conveying device, used to move the scanned object along a predetermined conveying direction in a single linear scanning channel, wherein the conveying device comprises a conveying surface on which the scanned object u is placed; p scanning sections, each scanning section comprising a plurality of ray sources and at least one detector, the p scanning sections being arranged at intervals along the transmission direction, wherein p is a positive integer greater than or equal to 2, and in each scanning section, the plurality of ray sources are used to alternately emit ray beams to form a scanning area, the plurality of ray sources are located on one side of the scanning channel and are sequentially arranged at intervals; the at least one detector is located on the other side of the scanning channel and is used to detect projection data formed after the ray beams pass through the scanning object when the scanning object passes through the scanning area; and An imaging device is used to generate a three-dimensional reconstructed image of the scanned object based on the projection data detected by each detector in the p scanning segments.

2. The system of claim 1, wherein: The p scanning segments include an i-th scanning segment and a j-th scanning segment, wherein i and j are both positive integers greater than or equal to 1 and less than or equal to p, and i and j are not equal; The i-th scanning segment includes mi ray sources and ni detectors, where mi is a positive integer greater than or equal to 2, and ni is a positive integer greater than or equal to 1; The j-th scanning segment includes mj ray sources and nj detectors, where mj is a positive integer greater than or equal to 2, and nj is a positive integer greater than or equal to 1; and Observing along the scanning channel, the mi ray sources and the ni detectors are arranged on both sides of the scanning channel along a first arrangement direction, and the mj ray sources and the nj detectors are arranged on both sides of the scanning channel along a second arrangement direction.

3. The system of claim 2, wherein: The first arrangement direction and the second arrangement direction are different.

4. A system as claimed in claim 2 or 3, wherein: Orthographic projections of the first arrangement direction and the second arrangement direction in a plane perpendicular to the conveying direction intersect.

5. The system of claim 4, wherein: Orthographic projections of the first arrangement direction and the second arrangement direction in a plane perpendicular to the conveying direction are perpendicular.

6. The system of claim 4, wherein: The first arrangement direction is parallel to a width direction of the scanning channel, and the first arrangement direction is parallel to the conveying surface.

7. The system of claim 4 or 6, wherein: The second arrangement direction is parallel to a height direction of the inspection object, and the second arrangement direction is perpendicular to the conveying surface.

8. The system of claim 3, wherein: The first arrangement direction forms a first inclination angle with the conveying surface, and the first inclination angle is greater than 0° and less than 90°; and / or, The second arrangement direction forms a second inclination angle with the conveying surface, and the second inclination angle is greater than 0° and less than 90°.

9. The system of claim 2, wherein: Orthographic projections of the first arrangement direction and the second arrangement direction in a plane perpendicular to the conveying direction coincide with each other.

10. The system of claim 2, 3 or 9, wherein: A first relative position of the mi ray sources relative to the ni detectors in the transmission direction is different from a second relative position of the mj ray sources relative to the nj detectors in the transmission direction.

11. The system of claim 10, wherein: The ni detectors include a first row of detector modules arranged at the front in the conveying direction, and the nj detectors include a first row of detector modules arranged at the front in the conveying direction; as well as Observing along a direction perpendicular to the transmission surface, the mi ray sources are located at a first offset distance relative to the first row of detector modules of the ni detectors in the transmission direction, and the mj ray sources are located at a second offset distance relative to the first row of detector modules of the nj detectors in the transmission direction, and the first offset distance is not equal to the second offset distance.

12. The system of any one of claims 2 to 11, wherein: ni=1, the ni detectors are area array detectors; and / or, nj=1, the nj detectors are area array detectors.

13. The system of any one of claims 2 to 11, wherein: ni is greater than or equal to 2, and the ni detectors are respectively linear detector columns; and / or nj is greater than or equal to 2, and the nj detectors are respectively linear detector arrays.

14. The system of claim 13, wherein: The ni detectors are arranged at intervals along the transmission direction, and / or the nj detectors are arranged at intervals along the transmission direction.

15. The system of claim 14, wherein: The ni detectors are arranged at equal intervals along the transmission direction, or the ni detectors are arranged at equal angular intervals along the transmission direction; and / or, The nj detectors are arranged at equal intervals along the transmission direction, or the nj detectors are arranged at equal angular intervals along the transmission direction.

16. The system of any one of claims 12 to 15, wherein: A first surface angle is formed between the detection surfaces of the ni detectors and the transmission surface, and a second surface angle is formed between the detection surfaces of the nj detectors and the transmission surface. The first surface angle is not equal to the second surface angle.

17. The system of claim 16, wherein: The first face angle is about 90°, and the second face angle is about 0°.

18. The system of any one of claims 12-15, wherein: A first surface angle is formed between the detection surfaces of the ni detectors and the transmission surface, and a second surface angle is formed between the detection surfaces of the nj detectors and the transmission surface, and the first surface angle is equal to the second surface angle.

19. The system of any one of claims 2 to 18, wherein: The mi ray sources are sequentially arranged at intervals along a first straight line, where the first straight line is an imaginary straight line extending along a first direction, and the first direction is perpendicular to the transmission surface; and / or, The mj ray sources are sequentially arranged at intervals along a second straight line, where the second straight line is an imaginary straight line extending along a second direction, and the second direction is perpendicular to both the first direction and the transmission direction.

20. The system of any one of claims 2 to 19, wherein: The beam emission directions of the mi ray sources are all the same, and / or the beam emission directions of the mj ray sources are all the same; or, At least two of the mi ray sources have different beam-emitting directions; and / or at least two of the mj ray sources have different beam-emitting directions.

21. The system of any one of claims 2 to 20, wherein: The ray beam emitted by at least one of the mi ray sources is a cone ray beam, and the cone ray beam includes a main beam surface in a first fan angle direction and a main beam surface in a first cone angle direction; and The ray beam emitted by at least one ray source among the mj ray sources is a cone ray beam, and the cone ray beam includes a main beam surface in the second fan angle direction and a main beam surface in the second cone angle direction.

22. The system of claim 21, wherein: The main beam plane in the first fan angle direction is parallel to the main beam plane in the second fan angle direction; and / or, The main beam surface in the first cone angle direction and the main beam surface in the second cone angle direction are not parallel.

23. The system of claim 21, wherein: The main beam plane in the first fan angle direction and the main beam plane in the second fan angle direction are not parallel; and / or, The main beam surface in the first cone angle direction is parallel to the main beam surface in the second cone angle direction.

24. The system of any one of claims 21-23, wherein: The main beam surface in the first fan angle direction is perpendicular to the transmission surface, and the main beam surface in the first fan angle direction is perpendicular to the transmission direction; or, the main beam surface in the first fan angle direction is perpendicular to the transmission surface, and the main beam surface in the first fan angle direction forms a first angle with respect to the transmission direction, and the first angle is greater than 90° and less than 180°; or, the main beam surface in the first fan angle direction forms a first angle with respect to the transmission surface, and the first angle is not equal to 90°, and the main beam surface in the first fan angle direction is perpendicular to the transmission direction; or, the main beam surface in the first fan angle direction forms a first angle with respect to the transmission surface, and the first angle is not equal to 90°, and the main beam surface in the first fan angle direction forms a first angle with respect to the transmission direction, and the first angle is greater than 90° and less than 180°; and / or, The main beam surface in the second fan angle direction is perpendicular to the transmission surface, and the main beam surface in the second fan angle direction is perpendicular to the transmission direction; Alternatively, the main beam surface in the second fan angle direction is perpendicular to the transmission surface, the main beam surface in the second fan angle direction forms a second angle with respect to the transmission direction, and the second angle is greater than 0° and less than 90°; alternatively, the main beam surface in the second fan angle direction forms a second angle with respect to the transmission surface, the second angle is not equal to 90°, and the main beam surface in the second fan angle direction is perpendicular to the transmission direction; alternatively, the main beam surface in the second fan angle direction forms a second angle with respect to the transmission surface, the second angle is not equal to 90°, and the main beam surface in the second fan angle direction forms a second angle with respect to the transmission direction, and the second angle is greater than 0° and less than 90°.

25. The system of any one of claims 21-24, wherein: The main beam surface in the first cone angle direction is parallel to the transmission surface, or the main beam surface in the first cone angle direction is perpendicular to the transmission surface, or the main beam surface in the first cone angle direction forms a third angle with respect to the transmission surface, and the third angle is greater than 0° and less than 90°; and / or, The main beam surface in the second cone angle direction is parallel to the transmission surface, or the main beam surface in the second cone angle direction is perpendicular to the transmission surface, or the main beam surface in the second cone angle direction forms a fourth angle with respect to the transmission surface, and the fourth angle is greater than 0° and less than 90°.

26. The system of any one of claims 21-25, wherein: The main beam surface in the first fan angle direction includes a first cone angle, and the first cone angle corresponds to the size of at least one detector among the ni detectors in the first arrangement direction, and the first arrangement direction is perpendicular to the first arrangement direction; and / or, The main beam surface in the second fan angle direction includes a second cone angle, and the second cone angle corresponds to the size of at least one detector among the nj detectors in the first arrangement direction, and the first arrangement direction is perpendicular to the second arrangement direction; and / or, The main beam surface in the first cone angle direction includes a first fan angle, and the first fan angle corresponds to the size of the ni detectors in the second arrangement direction, and the second arrangement direction is parallel to the transmission direction; and / or, The main beam surface in the second cone angle direction includes a second fan angle, and the second fan angle corresponds to the size of the nj detectors in the second arrangement direction, and the second arrangement direction is parallel to the transmission direction.

27. The system of any one of claims 1 to 26, wherein: The scanning object includes at least one of a container, a car and a truck, and the multiple radiation sources include MeV energy level accelerators respectively; or, The scanning object includes at least one of a suitcase and a package, and the multiple radiation sources include KeV energy level X-ray machines.

28. A CT scanning imaging method applied to the system according to any one of claims 1 to 27, wherein: The method comprises: The conveying device drives the scanning object to move along a predetermined conveying direction in the scanning channel, wherein the conveying device includes a conveying surface for placing the scanning object; Controlling the scanned object to sequentially pass through p scanning areas formed by p scanning segments, wherein before the scanned object enters the scanning range of the i-th scanning segment among the p scanning segments, controlling mi radiation sources in the i-th scanning segment to alternately emit radiation beams to form a scanning area, so that the scanned object passes through the scanning area of ​​the i-th scanning segment, and in the process of the scanned object passing through the scanning area of ​​the i-th scanning segment, controlling ni detectors in the i-th scanning segment to detect projection data formed after the radiation beam passes through the scanned object, wherein i and j are positive integers greater than or equal to 1 and less than or equal to p, mi is a positive integer greater than or equal to 2, and ni is a positive integer greater than or equal to 1; and A computer tomography image of the scanned object is generated according to a plurality of projection data formed by the detectors in the p scanning segments.

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