Imaging system for radiographic examination

Abstract

The present application relates to an imaging system for radiographic examination. Disclosed is an imaging system for radiographic examination, comprising: a first radiation source assembly comprising a plurality of radiation sources; a second radiation source assembly comprising a plurality of radiation sources, target points of all the radiation sources of the first radiation source assembly being arranged in a first radiation source plane, and target points of all the radiation sources of the second radiation source assembly being arranged in a second radiation source plane; a plurality of first detector units arranged in a first detector plane; a plurality of second detector units arranged in a second detector plane; and a detector support, the plurality of first detector units and the plurality of second detector units being both mounted on the detector support, wherein the first radiation source plane, the second radiation source plane, the first detector plane and the second detector plane are sequentially distributed along a travel direction.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fluoroscopy imaging, and in particular, to an imaging system for radiographic examination. BACKGROUND

[0002] Distributed radiation sources have been widely used in the field of fluoroscopy imaging, such as CT (Computed Tomography) devices for article inspection, medical diagnosis, etc. CT scanning generates three-dimensional scan images and has high recognition capability. According to the movement of the radiation source relative to the object under examination during the scanning process, existing CT scanning systems can include dynamic helical CT scanning systems and static CT scanning systems.

[0003] In a dynamic helical CT scanning system, the radiation source continuously rotates around the object under examination while the conveying device uniformly conveys the object under examination horizontally through the examination region during the scanning process. The dynamic helical CT scanning system usually requires a slip ring and a bearing, and the slip ring needs to rotate at a high speed during the scanning process. The existing static CT scanning system keeps the radiation source fixed during the entire scanning process and uses an integrated radiation source around the detection region for scanning.

[0004] Compared with the dynamic helical CT using a slip ring, the static CT scanning system can have a more flexible design. For example, the static CT scanning system can have different scanning channel sizes, device heights, and conveying speeds, etc. according to application requirements. The static CT scanning system can reduce noise and cost as it does not require a slip ring, etc., and can achieve instant scanning and termination, thereby shortening the preparation time.

[0005] According to the CT reconstruction theory, the scanned object needs to reach a certain scanning angle (e.g. at least 120 degrees) in the CT scanning system to meet the data completeness and ensure the accuracy of numerical reconstruction. A single distributed radiation source usually cannot meet this requirement due to the mechanical structure limitation. When multiple distributed radiation sources are arranged in combination, it is difficult to meet the data completeness requirement by arranging multiple distributed radiation sources in the same plane due to the structural interference between different radiation sources or between the radiation source and the detector. Usually, multiple (three or more) planes are needed, and a set of radiation sources and an opposite set of detectors are arranged in each plane, and the radiation beam plane of the radiation source coincides with the central plane of the detector. This arrangement increases the size of the entire system and the number of detectors.

[0006] Therefore, there is a need for an improved imaging system and method. SUMMARY

[0007] An object of the present application is to provide an imaging system capable of avoiding structural interference. An object of the present application is to provide an imaging system satisfying the need of CT reconstruction. An object of the present application is to provide an imaging system capable of improving imaging quality. An object of the present application is to provide an imaging system capable of reducing the size and cost of equipment. An object of the present application is to provide an imaging system capable of flexibly designing an optical path.

[0008] An aspect of the present application provides an imaging system for radiographic examination, comprising: an examination region, wherein an object under examination can be conveyed through the examination region along a direction of travel; a first source assembly comprising a plurality of sources; a second source assembly comprising a plurality of sources, wherein each source of the first source assembly and the second source assembly comprises a separate housing to define a vacuum space and comprises a plurality of target points enclosed within the housing, the target points of all sources of the first source assembly are arranged in a first source plane, the target points of all sources of the second source assembly are arranged in a second source plane; a plurality of first detector units for receiving X-rays emitted from the first source assembly and passing through the examination region, the plurality of first detector units are arranged in a first detector plane; a plurality of second detector units for receiving X-rays emitted from the second source assembly and passing through the examination region, the plurality of second detector units are arranged in a second detector plane; and a detector support, the plurality of first detector units and the plurality of second detector units are both mounted on the detector support, wherein the first source plane, the first detector plane, the second detector plane and the second source plane are distributed in sequence along the direction of travel.

[0009] According to certain embodiments of the present application, the first source plane, the first detector plane, the second detector plane and the second source plane are substantially perpendicular to the direction of travel and substantially parallel to each other.

[0010] According to certain embodiments of the present application, the imaging system is further configured to reconstruct a three-dimensional scan image of the object under examination based on detection data of the plurality of first detector units and the plurality of second detector units.

[0011] According to certain embodiments of the present application, the imaging system further comprises a source control device for controlling the emission of X-rays by the sources of the first source assembly and the second source assembly, wherein the source control device is configured such that at most one target point in the first source assembly emits X-rays and at most one target point in the second source assembly emits X-rays at the same time.

[0012] According to certain embodiments of the present application, the plurality of first detector units covers at least the range of X-ray emission of the first source assembly, and the plurality of second detector units covers at least the range of X-ray emission of the second source assembly.

[0013] According to certain embodiments of the present application, the plurality of first detector units are configured to extend completely around the examination region to form a first detector ring; and / or the plurality of second detector units are configured to extend completely around the examination region to form a second detector ring.

[0014] According to certain embodiments of the present application, the distribution of target points in the first source assembly does not completely overlap the distribution of target points in the second source assembly, as viewed in the direction of travel.

[0015] According to certain embodiments of the present application, the distribution of target points in the first source assembly is offset from the distribution of target points in the second source assembly, as viewed in the direction of travel.

[0016] According to certain embodiments of the present application, the projection of each source of the first source assembly does not completely fall within the projection of any source of the second source assembly, and the projection of each source of the second source assembly does not completely fall within the projection of any source of the first source assembly, as viewed in the direction of travel.

[0017] According to certain embodiments of the present application, the projections of the plurality of sources of the first source assembly are offset from the projections of the plurality of sources of the second source assembly, as viewed in the direction of travel.

[0018] According to certain embodiments of the present application, the target point of each source of the first source assembly is disposed to deflect in the direction of travel toward the plurality of first detector units by a first deflection angle, such that the X-rays emitted by each source of the first source assembly are not blocked by the plurality of first detector units prior to passing through the examination region; and / or the target point of each source of the second source assembly is disposed to deflect in the direction of travel toward the plurality of second detector units by a second deflection angle, such that the X-rays emitted by each source of the second source assembly are not blocked by the plurality of second detector units prior to passing through the examination region.

[0019] According to certain embodiments of the present application, the first source assembly further comprises a first collimator to deflect the direction of the X-rays emitted by the first source assembly in the direction of travel toward the plurality of first detector units by a first tilt angle; and / or the second source assembly further comprises a second collimator to deflect the direction of the X-rays emitted by the second source assembly in the direction of travel toward the plurality of second detector units by a second tilt angle.

[0020] According to certain embodiments of the present application, the first source assembly and the second source assembly have a combined scan angle relative to the examination region that is greater than 120 degrees, as viewed in the direction of travel.

[0021] According to some embodiments of the present application, the first and second radiation source assemblies have a combined scanning angle of more than 180 degrees relative to the examination region, as viewed in the direction of travel.

[0022] According to some embodiments of the present application, at least one of the target points of the first and second radiation source assemblies is a digital radiography (DR) target point, and the radiation source control device is configured such that the radiation emission frequency of the DR target point is higher than that of the other target points.

[0023] According to some embodiments of the present application, the first detector unit comprises a single row of detector crystals or a plurality of rows of detector crystals, and / or the second detector unit comprises a single row of detector crystals or a plurality of rows of detector crystals.

[0024] According to some embodiments of the present application, the imaging system has two radiation source assemblies and one detector assembly, the two radiation source assemblies form two radiation source planes, and the two radiation source planes are respectively located on two sides of the detector assembly, wherein the detector assembly comprises two groups of detector units, which respectively correspond to the two radiation source assemblies and form two detector planes. In some embodiments, the two groups of detector units are mounted on the same detector support, so as to effectively shorten the length and weight of the imaging device and reduce the difficulty of radiation protection. In some embodiments, the radiation sources in each radiation source assembly are arranged without interfering with each other, and each radiation source plane is arranged to be spaced apart from the corresponding detector plane, so that the imaging system can avoid interference between the radiation sources and between the radiation sources and the detectors, so as to have a larger scanning angle covering the examination region and provide more complete detection data. In some embodiments, each radiation source assembly comprises a plurality of radiation sources, and the detectors in the corresponding group of detector units can be shared by the plurality of radiation sources, so as to reduce the cost of the imaging system. In some embodiments, the target point distribution positions of the two radiation source assemblies can complement each other, so as to obtain more complete projection data and improve the imaging quality and accuracy. In some embodiments, the arrangement of the light source target points and the detectors of the imaging system and the light path design are more flexible, so as to meet more application requirements. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is a schematic view of an imaging system according to some embodiments of the present application.

[0026] Figure 2 is a perspective view of an imaging system according to some embodiments of the present application.

[0027] Figure 3 is a schematic view of a detector assembly according to some embodiments of the present application.

[0028] Figure 4is a schematic view of the relative positions of a radiation source assembly and a detector assembly according to certain embodiments of the present application.

[0029] Figure 5 is a schematic view of an imaging system according to certain embodiments of the present application.

[0030] Figure 6A is a schematic view of a radiation source and detector unit according to certain embodiments of the present application.

[0031] Figure 6B is a schematic view of a radiation source and detector unit according to certain embodiments of the present application.

[0032] Figure 7 is a schematic view of a target point distribution of an imaging system according to certain embodiments of the present application. DETAILED DESCRIPTION

[0033] In the following, embodiments of the present application are described with reference to the accompanying drawings. The following detailed description and drawings are used to illustrate the principles of the present application by way of example only, which is not limited to the preferred embodiments described. Rather, the scope of the present application is defined by the claims. The present application is now described with reference to the example embodiments illustrated in the drawings, in which some embodiments are illustrated by way of example. The following detailed description describes embodiments with reference to the drawings, in which like numerals indicate like elements, and in which:

[0034] An imaging system for radiographic inspection according to embodiments of the present application can be applied in an inspection system for performing a perspective imaging inspection of an object or a human body, etc.

[0035] According to certain embodiments of the present application, the inspection system can comprise an imaging system and a conveyor. The conveyor is configured to convey an object under inspection through an inspection region in a direction of travel. In example embodiments, the direction of travel is substantially parallel to a horizontal direction. In some embodiments, the conveyor conveys the object under inspection in a uniform linear motion.

[0036] Figure 1 is a schematic view of an imaging system according to certain embodiments of the present application. Figure 2 is a perspective view of an imaging system according to certain embodiments of the present application. Figure 3 is a schematic view of a detector assembly according to certain embodiments of the present application. Figure 4 is a schematic view of the relative positions of a radiation source assembly and a detector assembly according to certain embodiments of the present application.

[0037] According to certain embodiments of the present application, as Figure 1As shown, the imaging system includes two radiation source assemblies 10, 20 and a detector assembly 30. The radiation source assemblies 10, 20 are configured to emit X-rays. The detector assembly 30 is configured to receive X-rays emitted from the radiation source assemblies 10, 20 and passing through an examination region. According to certain embodiments of the present application, the radiation source assemblies 10, 20 and the detector assembly 30 remain stationary during operation of the imaging system, i.e., the imaging system is a static imaging system.

[0038] According to certain embodiments of the present application, the imaging system defines an examination region. In this context, an "examination region" means that an object under examination can be conveyed through the examination region in a direction of travel. When the object under examination is located in the examination region, X-rays emitted from the radiation source assemblies 10, 20 can penetrate the object under examination and be received by the detector assembly 30. In exemplary embodiments, the examination region includes a first end and a second end. In some embodiments, the object under examination is conveyed into the examination region from one of the first end and the second end and exits the examination region from the other one of the first end and the second end.

[0039] According to certain embodiments of the present application, as Figure 1 As shown, the imaging system can further include a shielding member 40. In exemplary embodiments, the shielding member 40 can be arranged to surround the examination region of the imaging system. In exemplary embodiments, the radiation source assemblies 10, 20 and the detector assembly 30 are arranged outside of the examination region, i.e., on a side of the shielding member 40 that is distal from the examination region.

[0040] The structure of the radiation source assemblies according to certain embodiments of the present application is described in detail below with reference to the accompanying drawings.

[0041] According to certain embodiments of the present application, the radiation source assembly 10 includes a plurality of radiation sources 100. According to certain embodiments of the present application, the radiation source assembly 20 includes a plurality of radiation sources 100. In Figure 1 and Figure 2 In certain embodiments as shown, the radiation source assemblies 10 and 20 include three radiation sources 100, respectively.

[0042] The above describes that the radiation source assembly 10 and the radiation source assembly 20 include a plurality of radiation sources 100, respectively. However, the present application is not limited thereto. According to certain embodiments of the present application, the radiation source assembly 10 or the radiation source assembly 20 can include one or more radiation sources 100.

[0043] According to certain embodiments of the present application, each radiation source 100 is a distributed radiation source. In exemplary embodiments, each radiation source 100 has a separate housing to define a separate vacuum space. Each radiation source 100 includes a plurality of target points (not shown) encapsulated within the housing. Figure 1 and Figure 2The plurality of target points of each of the ray sources 100 can have a uniform target point spacing in exemplary embodiments.

[0044] As described above, when the imaging system includes a plurality of ray sources 100, each of the ray sources 100 defines a separate vacuum space, and thus does not share the vacuum space with other ray sources 100. The vacuum spaces of different ray sources 100 are not communicated. According to certain embodiments of the present application, each of the ray sources 100 can be detached and / or installed in the imaging system independently from other ray sources 100.

[0045] In some embodiments, the plurality of target points of each of the ray sources 100 can be distributed along a straight line. In some embodiments, the shape of the housing of the ray source 100 can also correspond to the distribution of the target points. For example, when the target points of the ray source 100 are distributed along a straight line, the housing of the ray source 100 can also have a straight line-shaped outer contour, for example Figure 1 as shown.

[0046] The above describes that the plurality of target points in each of the ray sources 100 are arranged along a straight line. However, the present application is not limited thereto. In some embodiments, the plurality of target points in the ray source 100 can also be arranged along an arc line, a broken line, or the like. Figure 5 is a schematic view of an imaging system according to certain embodiments of the present application. In some embodiments, as shown in Figure 5 , the plurality of target points in the ray source 100 located below the examination region (not shown in Figure 5 ) are arranged along an arc line. Accordingly, the housing of the ray source 100 can also have an arc-shaped outer contour as viewed in the direction of travel. In this case, the arc-shaped contour of the ray source 100 can provide sufficient space for the installation of the transport device.

[0047] According to certain embodiments of the present application, the plurality of ray sources 100 of the ray source assembly 10 can have the same or different sizes. According to certain embodiments of the present application, the plurality of ray sources 100 of the ray source assembly 20 can have the same or different sizes. For example, as shown in Figure 1 and Figure 2 , the three ray sources of the ray source assembly 10 have two different sizes, and the three ray sources of the ray source assembly 20 also have two different sizes.

[0048] According to some embodiments of the present application, each of the radiation sources 100 of the radiation source assembly 10, 20 has a radiation emission range. According to some embodiments of the present application, when the radiation source assembly 10 includes a plurality of radiation sources 100, the plurality of radiation sources 100 of the radiation source assembly 10 can provide a combined radiation emission range. In some embodiments, the combined radiation emission range of the radiation source assembly 10 can be continuous or discontinuous. According to some embodiments of the present application, when the radiation source assembly 20 includes a plurality of radiation sources 100, the plurality of radiation sources 100 of the radiation source assembly 20 can provide a combined radiation emission range. In some embodiments, the combined radiation emission range of the radiation source assembly 20 can be continuous or discontinuous.

[0049] In some embodiments, the radiation emission range of the radiation source assembly 10, 20 is selected such that the entire examined object can fall within the radiation emission range. In this way, the entire examined object can be subjected to a complete perspective examination, thereby improving the imaging integrity of the imaging system.

[0050] In some embodiments, the radiation emission range of the radiation source assembly 10, 20 is selected such that a portion of interest of the examined object can fall within the radiation emission range. In this way, perspective examination can be focused only on the portion of interest of the examined object, thereby reducing the power consumption and cost of the imaging system while meeting the imaging requirements.

[0051] According to some embodiments of the present application, when the radiation source assembly 10 includes a plurality of radiation sources 100, the target points of all of the radiation sources 100 of the radiation source assembly 10 are arranged in a same plane (hereinafter referred to as "a first radiation source plane"), i.e., the plurality of radiation sources 100 of the radiation source assembly 10 are co-planar. According to some embodiments of the present application, when the radiation source assembly 20 includes a plurality of radiation sources 100, the target points of all of the radiation sources 100 of the radiation source assembly 20 are arranged in a same plane (hereinafter referred to as "a second radiation source plane"), i.e., the plurality of radiation sources 100 of the radiation source assembly 20 are co-planar. In this context, "the target points are arranged in a same plane" means that the beam exit points of the target points are arranged in a same plane.

[0052] In exemplary embodiments, the first radiation source plane is substantially parallel to the second radiation source plane. In some embodiments, the first radiation source plane is substantially perpendicular to the direction of travel. In some embodiments, the second radiation source plane is substantially perpendicular to the direction of travel.

[0053] According to certain embodiments of the present application, the plurality of radiation sources 100 of the radiation source assembly 10 are arranged without mutual interference. In some embodiments, when the radiation source assembly 10 includes a plurality of radiation sources 100, the plurality of radiation sources 100 of the radiation source assembly 10 are arranged to be spaced apart around the examination region. In some embodiments, when the radiation source assembly 10 includes a plurality of radiation sources 100, the plurality of radiation sources 100 of the radiation source assembly 10 are arranged to be continuously distributed around the examination region. In some embodiments, for example as shown in FIG. 1, as viewed in the direction of travel, the plurality of radiation sources 100 of the radiation source assembly 10 can include radiation sources 100 located below the examination region, radiation sources 100 located to the left of the examination region, and / or radiation sources 100 located to the right of the examination region. Figure 1

[0054] According to certain embodiments of the present application, the plurality of radiation sources 100 of the radiation source assembly 20 are arranged without mutual interference. In some embodiments, when the radiation source assembly 20 includes a plurality of radiation sources 100, the plurality of radiation sources 100 of the radiation source assembly 20 are arranged to be spaced apart around the examination region. In some embodiments, when the radiation source assembly 20 includes a plurality of radiation sources 100, the plurality of radiation sources 100 of the radiation source assembly 20 are arranged to be continuously distributed around the examination region. In some embodiments, for example as shown in FIG. 2, as viewed in the direction of travel, the plurality of radiation sources 100 of the radiation source assembly 20 can include radiation sources 100 located below the examination region, radiation sources 100 located to the left of the examination region, and / or radiation sources 100 located to the right of the examination region. Figure 1

[0055] The structure of the detector assembly according to certain embodiments of the present application is described in detail below with reference to the accompanying drawings.

[0056] According to certain embodiments of the present application, for example as shown in FIG. 3, the detector assembly 30 includes a plurality of first detector units 310, a plurality of second detector units 320, and a detector support 330. The plurality of first detector units 310 are configured to receive X-rays emitted from the radiation source assembly 10 and passing through the examination region. The plurality of second detector units 320 are configured to receive X-rays emitted from the radiation source assembly 20 and passing through the examination region. According to certain embodiments of the present application, the plurality of first detector units 310 and the plurality of second detector units 320 are both mounted on the detector support 330. Figure 3

[0057] According to certain embodiments of the present application, each of the detector units 310, 320 can be a single-energy detector unit, a dual-energy detector unit, or a spectral detector unit, etc. However, it should be understood that the type of detector unit of the present application is not limited to the above three types of detector units.

[0058] ​​​In example embodiments, the plurality of first detector units 310 are arranged in a same plane (hereinafter referred to as "first detector plane"). In example embodiments, the plurality of second detector units 320 are arranged in a same plane (hereinafter referred to as "second detector plane"). In this context, "detector units arranged in a same plane" means that the center planes of the detector units (e.g. the center planes of the detector crystals) are arranged in a same plane. For example, the center planes of the plurality of first detector units 310 or the plurality of second detector units 320 are arranged in a same plane by the same positioning reference. In some embodiments, the first detector units 310 comprise a single row of detector crystals or multiple rows of detector crystals, and / or the second detector units 320 comprise a single row of detector crystals or multiple rows of detector crystals.

[0059] In example embodiments, the first detector plane is substantially parallel to the second detector plane. In some embodiments, the first detector plane is substantially perpendicular to the direction of travel. In some embodiments, the second detector plane is substantially perpendicular to the direction of travel.

[0060] In some embodiments, the first ray source plane of the ray source assembly 10 is spaced apart from the first detector plane of the plurality of first detector units 310 along the direction of travel. In example embodiments, the first ray source plane of the ray source assembly 10 is substantially parallel to the first detector plane of the plurality of first detector units 310.

[0061] In some embodiments, the second ray source plane of the ray source assembly 20 is spaced apart from the second detector plane of the plurality of second detector units 320 along the direction of travel. In example embodiments, the second ray source plane of the ray source assembly 20 is substantially parallel to the second detector plane of the plurality of second detector units 320.

[0062] According to certain embodiments of the present application, the first ray source plane, the first detector plane, the second detector plane and the second ray source plane are sequentially arranged along the direction of travel. In example embodiments, for example as shown in FIG. 1, the ray source assembly 10 and the ray source assembly 20 are respectively arranged on two sides of the detector assembly 30 along the direction of travel. Thus, the imaging system according to certain embodiments of the present application has two ray source planes, which are respectively located on two sides of the detector assembly. Figure 2

[0063] In some embodiments, the first ray source plane, the first detector plane, the second detector plane and the second ray source plane are substantially parallel to each other. In some embodiments, the first ray source plane, the first detector plane, the second detector plane and the second ray source plane are substantially perpendicular to the direction of travel.

[0064] In some embodiments, the detector support 330 has a detector support center plane, for example as shown in FIG. 1.​Figure 2 In this context, the "detector support center plane" refers to a geometric center plane of the detector support 330 along the travel direction. According to certain embodiments of the present application, the detector support center plane is substantially parallel to the first and / or second ray source planes. In some embodiments, the detector support center plane is substantially parallel to the first and / or second detector planes. In exemplary embodiments, the detector support center plane is substantially perpendicular to the travel direction. According to certain embodiments of the present application, the first ray source plane, the detector support center plane and the second ray source plane are sequentially distributed along the travel direction. Thus, the imaging system according to certain embodiments of the present application has two ray source planes and one detector support center plane, the two ray source planes being located on two sides of the detector support center plane, respectively.

[0065] According to certain embodiments of the present application, the ray source assemblies 10, 20 and the detector assembly 30 are arranged without mutual interference. In some embodiments, along the travel direction, the plurality of ray sources 100 of the ray source assembly 10 is spaced apart from the adjacent outermost portion of the detector assembly 30 (e.g., the plurality of first detector units 310 or the outermost portion of the detector support 330 opposite to the ray source assembly 10) by a predetermined distance. In some embodiments, along the travel direction, the plurality of ray sources 100 of the ray source assembly 20 is spaced apart from the adjacent outermost portion of the detector assembly 30 (e.g., the plurality of second detector units 320 or the outermost portion of the detector support 330 opposite to the ray source assembly 20) by a predetermined distance. In some embodiments, as shown in FIG. 1, the detector units 310 (or 320) are spaced apart from the target points of the ray sources 100. Thus, the X-rays emitted by the ray source assemblies 10 or 20 will not be blocked by the detector assembly 30 before passing through the examination region. Figure 4

[0066] In some embodiments, the arrangement of the detector units in the detector assembly 30 can be set according to the arrangement of the ray sources 10, 20 and / or the size of the subject to be examined, etc. In some embodiments, the arrangement of the detector units in the detector assembly 30 can also employ a cost-effective arrangement, i.e., with as few detector units as possible to meet the imaging requirements.

[0067] According to certain embodiments of the present application, the plurality of first detector units 310 of the detector assembly 30 is arranged to cover at least the ray emission range of the ray source assembly 10. According to certain embodiments of the present application, the plurality of second detector units 320 of the detector assembly 30 is arranged to cover at least the ray emission range of the ray source assembly 20. Thus, the detector assembly 30 can cover the ray emission ranges of the ray source assemblies 10 and 20, and thus can cover the entire imaging range in the examination region. In this case, the arrangement of the detector assembly 30 can make full use of the X-rays emitted by the ray sources, improving the imaging quality and examination accuracy.​

[0068] In some embodiments, the plurality of first detector units 310 is arranged to cover at least a portion of the radiation emission range of the radiation source assembly 10 (e.g. corresponding to the radiation emission range of the portion of interest of the subject under examination). According to certain embodiments of the present application, the plurality of second detector units 320 is arranged to cover at least a portion of the radiation emission range of the radiation source assembly 20 (e.g. corresponding to the radiation emission range of the portion of interest of the subject under examination). Thereby, the detector assembly 30 can cover selected radiation emission ranges of the radiation source assemblies 10 and 20, and thereby can cover a main imaging range in the examination region. In this case, the arrangement of the detector assembly 30 can reduce the cost of the imaging system while ensuring sufficient imaging quality and examination accuracy.

[0069] In exemplary embodiments, the plurality of first detector units 310 of the detector assembly 30 extends completely around the examination region. Thereby, the plurality of first detector units 310 forms a complete and continuous first detector ring. In some embodiments, the first detector ring can be a circular ring, a square ring, a rectangular ring, a polygonal ring, etc. For example, as shown in Figs. 1 and 2, the plurality of first detector units 310 forms a square ring. Figure 2 and Figure 3 As shown in Figs. 3 and 4, the plurality of second detector units 320 forms a square ring.

[0070] In exemplary embodiments, the plurality of second detector units 320 of the detector assembly 30 extends completely around the examination region. Thereby, the plurality of second detector units 320 forms a complete and continuous second detector ring. In some embodiments, the second detector ring can be a circular ring, a square ring, a rectangular ring, a polygonal ring, etc. For example, as shown in Figs. 3 and 4, the plurality of second detector units 320 forms a square ring. Figure 2 and Figure 3 As shown in Figs. 3 and 4, the plurality of second detector units 320 forms a square ring.

[0071] The above describes that the plurality of first detector units 310 or the plurality of second detector units 320 forms a complete detector ring. However, the present application is not limited thereto. In certain embodiments, the detector ring formed by the plurality of first detector units 310 or the plurality of second detector units 320 can be incomplete, i.e. there are missing portions. In certain embodiments, the plurality of first detector units 310 is divided into multiple segments, and the first detector units 310 of different segments can be distributed at intervals around the examination region. In certain embodiments, the plurality of second detector units 320 is divided into multiple segments, and the second detector units 320 of different segments can be distributed at intervals around the examination region.

[0072] According to some embodiments of the present application, the imaging system can also be configured to reconstruct a three-dimensional scan (CT) image of the subject of examination based on the detection data of the first and second plurality of detector units 310 and 320 of the detector assembly 30. According to some embodiments of the present application, the imaging system can employ an iterative reconstruction algorithm, an analytic reconstruction algorithm, or a combination of different reconstruction algorithms when reconstructing the three-dimensional scan image of the subject of examination. For example, if the combined scan angle of the radiation source assemblies 10 and 20 with respect to the examination region is greater than 180 degrees, the imaging system can preferentially select an analytic reconstruction algorithm to improve the reconstruction speed and reduce the requirement on the computing performance. For example, if the combined scan angle of the radiation source assemblies 10 and 20 with respect to the examination region is less than 150 degrees, the imaging system can preferentially select an iterative reconstruction algorithm or use the analytic result as the initial value of the iterative algorithm. According to some embodiments of the present application, the identification algorithm employed by the imaging system can be based on the three-dimensional scan (CT) image or the digital radiography (DR) image alone, or both.

[0073] According to some embodiments of the present application, each radiation source 100 has a scan angle. In this context, the "scan angle" of each radiation source 100 refers to the range of angles of all target points of the radiation source 100 with respect to the examination region (e.g., with respect to the central axis of the examination region). In this context, the central axis of the examination region refers to an axis that passes through the approximate center of the examination region and is substantially perpendicular to the detector support center plane when viewed in the direction of travel. According to some embodiments of the present application, when the imaging system includes a plurality of radiation sources 100, the plurality of radiation sources 100 (all of the radiation sources 100 of the radiation source assemblies 10 and 20) at different scan positions with respect to the examination region can provide a combined scan angle. In this context, the "combined scan angle" refers to the scan angle resulting from the combination of the scan angles of the plurality of radiation sources 100 at the plurality of scan positions with respect to the examination region. In some embodiments, the combined scan angle of the plurality of radiation sources 100 at the plurality of scan positions with respect to the examination region can be continuous or discontinuous.

[0074] According to some embodiments of the present application, the radiation source assemblies 10 and 20 have a combined scan angle with respect to the examination region that is greater than 120 degrees when viewed in the direction of travel. When the combined scan angle of the imaging system is greater than 120 degrees, the imaging system is able to substantially achieve three-dimensional image reconstruction. In exemplary embodiments, the radiation source assemblies 10 and 20 have a combined scan angle with respect to the examination region that is greater than 180 degrees when viewed in the direction of travel. When the imaging system has a combined scan angle that exceeds 180 degrees, the imaging system is able to produce more complete scan data and produce better CT scanning results and better three-dimensional scan images.

[0075] According to certain embodiments of the present application, the imaging system is configured such that X-rays emitted by the radiation source assembly 10 are able to pass through the examination region and be received by the plurality of first detector units 310, and X-rays emitted by the radiation source assembly 20 are able to pass through the examination region and be received by the plurality of second detector units 320. In some embodiments, the imaging system is configured such that X-rays emitted by the radiation source assembly 10 are able to cover the first detector units 310 in the direction of travel, and / or X-rays emitted by the radiation source assembly 20 are able to cover the second detector units 320 in the direction of travel.

[0076] According to certain embodiments of the present application, the imaging system is configured such that X-rays emitted by each of the radiation sources 100 are not blocked by the detector assembly 30 prior to passing through the examination region. In exemplary embodiments, each of the first detector units 310 of the detector assembly 30 is positioned to not block X-rays emitted by one or more of the radiation sources 100 on the same side of the radiation source assembly 10, and is able to receive X-rays emitted by one or more of the radiation sources 100 on the other side of the radiation source assembly 10. In exemplary embodiments, each of the second detector units 320 of the detector assembly 30 is positioned to not block X-rays emitted by one or more of the radiation sources 100 on the same side of the radiation source assembly 20, and is able to receive X-rays emitted by one or more of the radiation sources 100 on the other side of the radiation source assembly 20.

[0077] The arrangement of radiation sources and detector units according to certain embodiments of the present application is described in detail below with reference to the accompanying drawings.

[0078] According to certain embodiments of the present application, the target point of each of the radiation sources 100 of the radiation source assembly 10 is positioned to deflect X-rays emitted by each of the radiation sources 100 of the radiation source assembly 10 by a first deflection angle in the direction of travel towards the plurality of first detector units 310, such that the X-rays emitted by each of the radiation sources 100 of the radiation source assembly 10 are able to pass through the examination region and be received by the plurality of first detector units 310. In some embodiments, the first deflection angle is positioned such that the X-rays emitted by each of the radiation sources 100 of the radiation source assembly 10 are able to cover the first detector units 310 in the direction of travel. In some embodiments, the first deflection angle is positioned such that the X-rays emitted by each of the radiation sources 100 of the radiation source assembly 10 are not blocked by the plurality of first detector units 310 prior to passing through the examination region.

[0079] According to certain embodiments of the present application, the target point of each of the x-ray sources 100 of the x-ray source assembly 20 is arranged to deflect the x-rays emitted by each of the x-ray sources 100 of the x-ray source assembly 20 by a second deflection angle in the direction of travel towards the plurality of second detector units 320, such that the x-rays emitted by each of the x-ray sources 100 of the x-ray source assembly 20 can pass through the examination region and be received by the plurality of second detector units 320. In some embodiments, the second deflection angle is arranged such that the x-rays emitted by each of the x-ray sources 100 of the x-ray source assembly 20 can cover the second detector units 320 in the direction of travel. In some embodiments, the second deflection angle is arranged such that the x-rays emitted by each of the x-ray sources 100 of the x-ray source assembly 20 are not blocked by the plurality of second detector units 320 before passing through the examination region.

[0080] In exemplary embodiments, the first deflection angle is equal to the second deflection angle.

[0081] Figure 6A A cross-sectional schematic view of an x-ray source and detector unit according to certain embodiments of the present application is shown. In exemplary embodiments, as shown, the x-ray source 100 is deflected by an angle in the direction of travel towards the detector unit 310 (or 320). Note that in Figure 6A the x-ray source 100 is deflected by an angle in the direction of travel towards the detector unit 310 (or 320). Note that in Figure 6A some embodiments, each x-ray source 100 is deflected about an axis of its target point. In exemplary embodiments, each x-ray source 100 is deflected such that the x-rays emitted by the x-ray source 100 can cover the corresponding detector unit 310 (or 320) in the direction of travel. By deflecting the x-ray source 100 relative to the detector unit, the x-rays emitted by the x-ray source 100 can be more effectively received by the corresponding detector unit. Furthermore, the x-rays emitted by the x-ray source 100 can avoid the detector unit on the same side and can also be received by the detector units on the other sides.

[0082] According to certain embodiments of the present application, the x-ray source assembly 10 can further comprise a collimator for deflecting the direction of the x-rays emitted by the x-ray sources 100 of the first x-ray source assembly 10 by a first tilt angle in the direction of travel towards the plurality of first detector units 310, such that the x-rays emitted by the x-ray sources 100 of the x-ray source assembly 10 can pass through the examination region and be received by the plurality of first detector units 310. In some embodiments, the first tilt angle is arranged such that the x-rays emitted by each of the x-ray sources 100 of the x-ray source assembly 10 can cover the first detector units 310 in the direction of travel. In some embodiments, the first tilt angle is arranged such that the x-rays emitted by each of the x-ray sources 100 of the x-ray source assembly 10 are not blocked by the plurality of first detector units 310 before passing through the examination region.

[0083] According to certain embodiments of the present application, the ray source assembly 20 can further comprise a collimator for deflecting the direction of the X-rays emitted by the ray source 100 of the second ray source assembly 20 by a second tilt angle along the travel direction towards the plurality of second detector units 320, such that the X-rays emitted by the ray source 100 of the ray source assembly 20 can pass through the examination region and be received by the plurality of second detector units 320. In some embodiments, the second tilt angle is set such that the X-rays emitted by each ray source 100 of the ray source assembly 20 can cover the second detector units 320 in the travel direction. In some embodiments, the second tilt angle is set such that the X-rays emitted by each ray source 100 of the ray source assembly 20 are not blocked by the plurality of second detector units 320 before passing through the examination region.

[0084] In exemplary embodiments, the first tilt angle is equal to the second tilt angle.

[0085] Figure 6B A cross-sectional view of a ray source and a detector unit according to certain embodiments of the present application is shown. In exemplary embodiments, as shown in Figure 6B the X-rays emitted by the ray source 100 are constrained by a collimator (shown as a shaded portion), such that the direction of the X-rays emitted by the ray source 100 is deflected by an angle towards the detector unit 310 (or 320). Note that Figure 6B only one detector unit opposite the ray source 100 is shown, and not the detector unit on the same side as the ray source 100. In exemplary embodiments, the collimator is configured to deflect the X-rays emitted by the ray source 100 to cover the corresponding detector unit 310 (or 320) in the travel direction. By deflecting the direction of the X-rays emitted by the ray source 100 by the collimator, the X-rays emitted by the ray source 100 can be more effectively received by the corresponding detector unit. In addition, the X-rays emitted by the ray source 100 can avoid the detector unit on the same side, and can also be received by the detector unit on the other side.

[0086] The above describes deflecting the ray source or using a collimator to enable the X-rays to be received by the detector unit. However, the present application is not limited thereto. According to certain embodiments of the present application, the ray source 100 of the imaging system can also be configured such that the emitted X-rays have a sufficiently wide beam width along the travel direction to cover the detector unit 310 or 320 in the travel direction. For example, the collimator of the ray source 100 can have a wider slit width. In this case, part of the X-rays emitted by the ray source 100 can fall outside the receiving range of the detector unit. In some embodiments, the imaging system can further provide an additional shielding component (e.g. provided on one side of the detector unit along the travel direction) to shield the X-rays falling outside the receiving range of the detector unit.

[0087] In some embodiments, the detector assembly 30 is disposed closer to the center of the examination region relative to the source assemblies 10, 20. In some embodiments, when the imaging system includes multiple source assemblies 100, the detector assembly 30 is disposed closer to the center of the examination region relative to all of the source assemblies 100. As such, the detector assembly 30 is disposed radially inward of the source assemblies 10, 20.

[0088] According to certain embodiments of the present application, the number of target points in the source assembly 10 can be the same or different from the number of target points in the source assembly 20. According to certain embodiments of the present application, the distribution of the target points in the source assembly 10 does not completely overlap the distribution of the target points in the source assembly 20 as viewed along the direction of travel. Figure 7 is a schematic diagram of the target point distribution of an imaging system according to certain embodiments of the present application. In some embodiments, as shown in Figure 7 , the distribution of the target points in the source assemblies 10 and 20 does not completely overlap. As such, the distribution of the target points of the source assembly 10 and the source assembly 20 can complement each other to increase the number of target points for effective imaging and to provide a larger combined scan angle.

[0089] In some embodiments, the distribution of the target points in the source assembly 10 does not completely overlap the distribution of the target points in the source assembly 20 as viewed along the direction of travel. As such, the distribution of the target points in the source assemblies 10 and 20 avoids having two target points at the same location. Thus, the imaging system can take full advantage of the completely interleaved target points of the source assemblies 10 and 20 for imaging and can improve the imaging accuracy and quality.

[0090] According to certain embodiments of the present application, the projection of each source 100 of the source assembly 10 does not completely fall within the projection of any source 100 of the source assembly 20 and the projection of each source 100 of the source assembly 20 does not completely fall within the projection of any source 100 of the source assembly 10 as viewed along the direction of travel. In this case, for example, as shown in Figure 1 and Figure 2 , the arrangement of the sources 100 in the source assembly 10 and the source assembly 20 is not completely uniform, there is no source 100 in the source assembly 10 and 20 that completely overlaps each other or there is no source 100 that completely falls within the range of another source 100. As such, the range of the radiation emission and the scan range of the source assembly 10 and the source assembly 20 can complement each other to increase the number of target points for effective imaging and to provide a larger combined scan angle.

[0091] In some embodiments, the projections of the plurality of radiation sources 100 of the radiation source assembly 10 are staggered with the projections of the plurality of radiation sources 100 of the radiation source assembly 20, as viewed in the direction of travel. In this case, the individual radiation sources 100 in the radiation source assembly 10 and the radiation source assembly 20 are arranged completely interleaved with each other. In this way, the imaging system can make full use of all the radiation sources of the radiation source assemblies 10 and 20 for imaging, and the imaging precision and quality can be improved.

[0092] According to some embodiments of the present application, the imaging system can further comprise a radiation source control device. The radiation source control device is configured to control the radiation emission of the radiation source assemblies 10 and 20. In some embodiments, the radiation source control device is configured such that at most one target point in the radiation source assembly 10 and at most one target point in the radiation source assembly 20 emit X-rays at the same time. In this way, there will be no more than two target points in the first radiation source plane and no more than two target points in the second radiation source plane emitting X-rays at the same time. At the same time, there can be one target point from the first radiation source plane and one target point from the second radiation source plane emitting X-rays at the same time. According to some embodiments of the present application, the radiation source control device can be configured to control the radiation emission of the radiation source assemblies 10 and 20, such as the emission sequence, the emission frequency, the emission current, etc., respectively.

[0093] According to some embodiments of the present application, at least one target point of the radiation source assemblies 10 and 20 is a digital radiography (DR) target point. The X-rays emitted by the DR target point can be used to generate a DR image after being received by the detector assembly 30. In this way, the imaging system according to some embodiments of the present application can be used for both CT imaging and DR imaging. In some embodiments, the radiation source control device is configured such that the radiation emission frequency of the digital radiography target point is higher than that of the other target points. In some embodiments, the imaging system comprises a plurality of DR target points selected from the radiation source assemblies 10 and 20. In some embodiments, when the imaging system has a plurality of DR target points, the DR target points can be at different scanning positions with respect to the examination region, i.e. for generating DR images at different viewing angles.

[0094] The above describes selecting one or more target points in the radiation source assemblies 10 and 20 as DR target points. However, the present application is not limited thereto, and in some embodiments, the imaging system can further provide a separate DR target point, i.e. the DR target point is independent of the target points in the radiation source assemblies 10 and 20. In this case, the imaging system can further provide a separate DR detector unit to receive the X-rays emitted by the separate DR target point.

[0095] It should be understood that the arrangement, number and shape of the ray source and the detector unit described above are only exemplary and should not be considered as a limitation of the present application.

[0096] The imaging method according to certain embodiments of the present application will be described in detail below. The imaging method can be implemented using any of the imaging systems described above according to certain embodiments of the present application.

[0097] The imaging method according to certain embodiments of the present application will be described below with the example that the object to be examined passes through the ray source assembly 10 and the ray source assembly 20 in sequence. However, it should be understood that the object to be examined can also pass through the ray source assembly 20 and the ray source assembly 10 in sequence.

[0098] In step S10, the object to be examined is carried on the conveying device, and the conveying device conveys the object to be examined through the examination region along the advancing direction. In step S20, the target points of the ray source assemblies 10, 20 are controlled to emit X-rays in a predetermined order. In step S30, the emitted X-rays pass through the object to be examined located in the examination region and are received by the detector assembly 30.

[0099] In some embodiments, the imaging method can further include step S40: reconstructing a three-dimensional scan image of the object to be examined according to the detection data of the plurality of first detector units 310 and the plurality of second detector units 320. In some embodiments, the imaging method can further include identifying the object to be examined and providing an identification result after reconstructing the three-dimensional scan image of the object to be examined. In some embodiments, the imaging method can further include displaying the three-dimensional scan image and / or the identification result.

[0100] In some embodiments, before step S10 is performed, the imaging method can further pre-load or produce configuration information or correction information, such as background data, air data, etc.

[0101] In some embodiments, the imaging method can further include detecting whether the object to be examined enters the beam face of the X-rays emitted by the ray source assembly 10 by the plurality of first detector units 310 of the detector assembly 30. In some embodiments, the imaging method can further include detecting whether the object to be examined enters the beam face of the X-rays emitted by the ray source assembly 20 by the plurality of second detector units 320 of the detector assembly 30. For example, by detecting whether the object to be examined enters the beam face of the X-rays of the ray source assemblies 10, 20 in real time, the imaging method can provide a reference for subsequent operations.

[0102] In some embodiments, the imaging method can further include buffering and / or pre-processing the detection data of the first plurality of detector units 310 when it is determined that the object under examination enters the beam face of the X-rays emitted by the radiation source assembly 10. In some embodiments, the imaging method can start reconstructing a three-dimensional scan image of the object under examination from the detection data of the first plurality of detector units 310 and the second plurality of detector units 320 when it is determined that the object under examination enters the beam face of the X-rays emitted by the radiation source assembly 20. In some embodiments, the imaging method can further include controlling the radiation source assemblies 10, 20 to stop emitting X-rays when it is determined that the object under examination has completely passed the beam face of the X-rays emitted by the radiation source assembly 20.

[0103] In some embodiments, the imaging method can further include controlling the DR target to emit X-rays to generate a DR image. In some embodiments, when a separate DR target is provided, the imaging method can receive, by a separate DR detector unit, X-rays emitted by the separate DR target and passing through the object under examination. In some embodiments, when one or more targets in the radiation source assemblies 10 and 20 are selected as the DR target, the imaging method can receive, by the detector assembly 30, X-rays emitted by the DR target and passing through the object under examination.

[0104] In the imaging method according to certain embodiments of the present application, other implementations of the imaging system used are described above and are incorporated into the embodiments of the imaging method accordingly, and are not repeated here.

[0105] While the application has been described with reference to example embodiments, it will be understood by those skilled in the art that various changes can be made and equivalents can be substituted for elements thereof without departing from the scope of the application. In addition, many modifications can be made to adapt a particular situation or material to the teachings of the application without departing from the central inventive concept described herein. Additionally, while a number of example combinations have been shown and described, other combinations, including more, fewer, or only a single element from the combinations, are also within the scope of the application.

Claims

1. An imaging system for radiographic examination, comprising: An inspection area, through which the object to be inspected can be conveyed in the direction of travel; A first radiation source assembly includes a plurality of radiation sources, each radiation source of the first radiation source assembly including a separate housing to define a vacuum space and including a plurality of target points encapsulated within the housing, and the target points of all radiation sources of the first radiation source assembly are arranged in the plane of the first radiation source. The second radiation source assembly includes multiple radiation sources. Each radiation source in the second radiation source assembly includes a separate housing to define a vacuum space and includes multiple target points encapsulated within the housing. The target points of all radiation sources in the second radiation source assembly are arranged in the plane of the second radiation source. A plurality of first detector units are provided for receiving X-rays emitted from the first X-ray source assembly and passing through the inspection area, the plurality of first detector units being arranged in a first detector plane; A plurality of second detector units are provided for receiving X-rays emitted from the second X-ray source assembly and passing through the inspection area, and the plurality of second detector units are arranged in the plane of the second detector. and A single detector bracket, on which the plurality of first detector units and the plurality of second detector units are mounted. The first radiation source plane, the first detector plane, the second detector plane, and the second radiation source plane are arranged at intervals and sequentially along the direction of travel, and The first ray source plane, the first detector plane, the second detector plane, and the second ray source plane are substantially perpendicular to the direction of travel and substantially parallel to each other.

2. The imaging system according to claim 1, wherein, The imaging system is also configured to reconstruct a three-dimensional scan image of the object being inspected based on the detection data from the plurality of first detector units and the plurality of second detector units.

3. The imaging system of claim 2 further includes a radiation source control device for controlling radiation emission from the first radiation source assembly and the second radiation source assembly, wherein the radiation source control device is configured such that at most one target point in the first radiation source assembly emits X-rays and at most one target point in the second radiation source assembly emits X-rays at any given time.

4. The imaging system according to claim 1, wherein, The plurality of first detector units at least cover the radiation emission range of the first radiation source assembly, and the plurality of second detector units at least cover the radiation emission range of the second radiation source assembly.

5. The imaging system according to claim 4, wherein, The plurality of first detector units are configured to extend completely around the inspection area to form a first detector ring; and / or The plurality of second detector units are configured to extend completely around the inspection area to form a second detector ring.

6. The imaging system according to claim 1, wherein, When observed along the direction of travel, the distribution positions of the target points in the first radiation source assembly and the distribution positions of the target points in the second radiation source assembly do not completely overlap.

7. The imaging system according to claim 6, wherein, When viewed along the direction of travel, the distribution positions of the target points in the first radiation source assembly and the distribution positions of the target points in the second radiation source assembly are staggered.

8. The imaging system according to claim 1, wherein, When viewed along the direction of travel, the projection of each ray source of the first ray source assembly does not fall completely within the projection of any ray source of the second ray source assembly, and the projection of each ray source of the second ray source assembly does not fall completely within the projection of any ray source of the first ray source assembly.

9. The imaging system according to claim 8, wherein, When viewed along the direction of travel, the projections of the multiple radiation sources of the first radiation source assembly are offset from the projections of the multiple radiation sources of the second radiation source assembly.

10. The imaging system according to claim 1, wherein, The target point of each radiation source in the first radiation source assembly is configured to deflect a first deflection angle toward the plurality of first detector units along the travel direction, so that the X-rays emitted by each radiation source in the first radiation source assembly are not blocked by the plurality of first detector units before passing through the inspection area. and / or The target point of each radiation source in the second radiation source assembly is configured to deflect a second deflection angle toward the plurality of second detector units along the direction of travel, such that the X-rays emitted by each radiation source in the second radiation source assembly are not blocked by the plurality of second detector units before passing through the inspection area.

11. The imaging system according to claim 1, wherein, The first X-ray source assembly further includes a first collimator for deflecting the direction of the X-rays emitted by the first X-ray source assembly toward the plurality of first detector units by a first tilt angle along the direction of travel; and / or The second X-ray source assembly further includes a second collimator for deflecting the direction of the X-rays emitted by the second X-ray source assembly toward the plurality of second detector units by a second tilt angle along the direction of travel.

12. The imaging system according to claim 1, wherein, When viewed along the direction of travel, the first X-ray source assembly and the second X-ray source assembly have a combined scanning angle of more than 120 degrees relative to the inspection area.

13. The imaging system according to claim 12, wherein, When viewed along the direction of travel, the first X-ray source assembly and the second X-ray source assembly have a combined scanning angle of more than 180 degrees relative to the inspection area.

14. The imaging system according to claim 3, wherein, At least one target of the first radiation source assembly and the second radiation source assembly is a digital imaging (DR) target, and the radiation source control device is configured such that the radiation emission frequency of the digital imaging target is higher than the radiation emission frequency of other targets.

15. The imaging system according to claim 1, wherein, The first detector unit includes a single-row detector crystal or a multi-row detector crystal, and / or the second detector unit includes a single-row detector crystal or a multi-row detector crystal.

Images