Radiation Scanning Device

Abstract

The radiation scanning device includes a transmission device (1) for transporting a subject (6) through a scanning area of ​​the radiation scanning device, a radiation source (3) including a plurality of radiation source modules (31, 32, 33, 34) each having at least one radiation source point, the plurality of radiation source modules (31, 32, 33, 34) being arranged to surround the scanning area in a non-closed structure opening to one side of the scanning area as viewed along the transport direction of the subject (6), and a front end of a non-closed structure having ends connected to each other and opening to one side of the scanning area as viewed along the transport direction of the subject. and a detector (4) comprising a plurality of detector groups (41, 42, 43, 44) arranged to surround the scanning area and detecting radiation transmitted through the subject (6) during scanning, wherein an opening of the non-enclosed structure of the radiation source (3) and an opening of the non-enclosed structure of the detector are installed opposite each other, the plurality of detector groups (41, 42, 43, 44) of the detector (4) are fixed in the same plane perpendicular to the transport direction of the subject (6), and the plurality of radiation source modules (31, 32, 33, 34) of the radiation source (3) are arranged in a plurality of different planes perpendicular to the transport direction of the subject (6).

Description

[Technical Field]

[0001] This application claims priority to Chinese Patent Application No. 202110770212.8, entitled "Radiation Scanning Apparatus," filed on July 7, 2021, the entire contents of which are incorporated herein by reference.

[0002] The present application is in the field of data-based radiation imaging, and in particular relates to radiation scanning devices. [Background technology]

[0003] In conventional static computed tomography (CT) technology (distributed multi-point sources) or multiple viewing angles (single point sources) security inspection devices, multiple different viewing angles are usually arranged in different planes perpendicular or inclined to the transport direction of the object, or all radiation sources are concentrated in a single annular or rectangular sealed cavity. Most of the crystals in the detector array are perpendicular to the central plane of the radiation beam of the radiation source, and the same group of detector arrays corresponds to only one group of distributed multi-point sources or one single point source.

[0004] In the related art, there is also a static CT with a double-ring structure design that simulates the working principle of a slip-ring CT, in which the radiation source and detector are arranged in two different rings, and the radiation source ring and the detector ring are spaced apart at a certain interval along the transport direction of the subject. Summary of the Invention

[0005] The embodiments of the present application provide a radiation scanning device that can solve the problems of poor reliability and maintenance caused by concentrating multiple radiation sources in a single annular sealed cavity, and each detector group of the detector is shared by multiple radiation source modules, thereby reducing the cost of the device, facilitating detector replacement or maintenance when the coverage area of ​​the optical path is shortened as much as possible, and reducing the tilt angle between the center of the radiation beam and the surface of the detector, thereby improving image quality.

[0006] In a first aspect, an embodiment of the present application further provides a radiation scanning device comprising: a transmission device for transporting a subject through a scanning region of the radiation scanning device; a radiation source comprising a plurality of radiation source modules including at least one radiation source point for emitting a radiation beam, the plurality of radiation source modules being arranged above the transmission device around the scanning region and fixed in a plane perpendicular to the transport direction of the subject; and a detector for detecting radiation transmitted through the subject during scanning, the detector comprising a plurality of detector groups, the ends of the plurality of detector groups being connected to each other and arranged around the scanning region, the ends of the plurality of detector groups being fixed in a plane perpendicular to the transport direction of the subject, the detector being located between the radiation source and the scanning region along a direction perpendicular to the transport direction of the subject, the radiation source and the detector being arranged to at least partially overlap along the transport direction of the subject, and the plurality of radiation source modules being individually attachable and detachable from each other.

[0007] In the radiation scanning device according to this embodiment, the radiation source modules are arranged only above the transmission device so as to surround the scanning area, and no radiation source modules are arranged below the transmission device, and the detectors are arranged so as to surround the scanning area. As a result, such a radiation scanning device can reduce the height of the transmission device, making it easier to transfer the subject to the transmission device of the radiation scanning device, ensuring image quality and reducing manufacturing costs.

[0008] According to some embodiments, the radiation source modules are distributed multi-point sources, and the plurality of radiation source modules are arranged in a non-enclosed structure surrounding the scanning region and opening below the transmission device.

[0009] According to some embodiments, each of the plurality of radiation source modules is a linearly distributed multi-point source, and the plurality of linearly distributed multi-point sources are arranged above, to the left and to the right of the scanning region, and ends of the plurality of linearly distributed multi-point sources are directly connected or spaced apart.

[0010] According to some embodiments, the plurality of radiation source modules includes a plurality of first distributed multi-point sources and a plurality of second distributed multi-point sources, wherein the plurality of first distributed multi-point sources and the plurality of second distributed multi-point sources are alternately arranged, and are directly connected end to end or spaced apart.

[0011] According to some embodiments, the first distributed multi-point source is a linear distributed multi-point source and the second distributed multi-point source is a linear distributed multi-point source or an arc-shaped distributed multi-point source having a length shorter than that of the first distributed multi-point source.

[0012] According to some embodiments, each of the plurality of radiation source modules is a single point source group, and the plurality of single point source groups are arranged at least at a left field angle, a right field angle, a top field angle and a corner oblique field angle above the transmission device, and each single point source group includes at least two single point sources.

[0013] According to some embodiments, each radiation source module has a separate cavity for housing a respective radiation generating device.

[0014] According to some embodiments, the individual cavity of each radiation source module is provided with a mounting and positioning structure for mounting and positioning the radiation source module and for rotating the radiation source module to adjust the beam output angle of the radiation beam.

[0015] According to some embodiments, each detector group is a detector array including multiple detector units, and the multiple detector groups are arranged in a closed square, rectangular, polygonal, or elliptical structure surrounding the scanning area.

[0016] According to some embodiments, each detector group is a linear detector array, and the detector includes four linear detector arrays, which are arranged on four sides of the scanning area, above, below, left and right, forming a rectangular or square structure.

[0017] According to some embodiments, each detector group is a linear detector array, and the detector includes a plurality of first linear detector arrays and a plurality of second linear detector arrays, the second linear detector arrays being shorter than the first linear detector arrays, and the first linear detector arrays and the second linear detector arrays being alternately arranged around the scanning region to form a polygonal structure.

[0018] According to some embodiments, each detector group of detectors is independently detachable from the others.

[0019] According to some embodiments, each detector group of the detectors is attached and detached by being moved along the transport direction of the object to be detected.

[0020] According to some embodiments, each detector group of the detectors is configured such that some detector groups are attached and detached by moving them along the transport direction of the subject, and other detector groups are attached and detached by moving them along a direction perpendicular to the transport direction of the subject.

[0021] According to some embodiments, each detector group of the detectors includes a detector arm, the radiation scanning device includes a support frame fixed to a mounting base of the radiation scanning device, and the detector group is attached to or detached from the support frame by moving via the detector arm along the transport direction of the subject or a direction perpendicular to the transport direction of the subject.

[0022] According to some embodiments, each detector group of the detectors is configured to avoid the radiation beam of the radiation source module on the same side and to receive radiation of all remaining radiation source modules on the other side except the radiation source module on the same side.

[0023] According to some embodiments, each detector unit of the detector group includes a detector crystal for receiving radiation transmitted through the subject during scanning, the detector crystal being positioned at an end of the detector unit along the transport direction of the subject, adjacent to the edge of the radiation beam of the radiation source module on the same side in the transport direction of the subject, but not blocking the radiation beam.

[0024] According to some embodiments, each radiation source module of the radiation source is arranged such that the radiation beam avoids the detector group on the same side and illuminates the detector crystals of the detector group on the opposite side.

[0025] According to some embodiments, each radiation source module is configured to rotate about a target axis such that a central position of the radiation beam illuminates a detector crystal of an opposing detector bank.

[0026] According to some embodiments, the radiation scanning device further comprises an image processing module arranged to perform data compensation and / or reconstruction image restoration for missing projection data at the ends of the radiation source module to obtain a complete reconstructed image.

[0027] According to some embodiments, the image processing module is configured to perform image reconstruction by an iterative method, an image region inpainting method or a combination of both.

[0028] In a second aspect, an embodiment of the present application further provides a radiation scanning device comprising: a transmission device for transporting a subject through a scanning region of the radiation scanning device; a radiation source including a plurality of radiation source modules including at least one radiation source point for emitting a radiation beam, the radiation source being arranged around the scanning region in a non-enclosed structure that opens to the left or right side of the scanning region and fixed in a plane perpendicular to a transport direction of the subject; and a detector for detecting radiation transmitted through the subject during scanning, the detector including a plurality of detector groups, the ends of the plurality of detector groups being connected to each other and arranged around the scanning region, and the plurality of detector groups being fixed in a plane perpendicular to the transport direction of the subject, the detector being located between the radiation source and the scanning region along a direction perpendicular to the transport direction of the subject, the radiation source and the detector being arranged to at least partially overlap each other along the transport direction of the subject, and the plurality of radiation source modules being individually attachable and detachable from each other.

[0029] In the radiation scanning device of this embodiment, the radiation source modules are arranged above, below, and on the left or right side of the scanning area so as to surround the scanning area, and the detectors are arranged so as to surround the scanning area. This radiation scanning device is applied to detecting baggage at airports, and takes advantage of the characteristics of baggage at airports, which are large in width and small in thickness, to take into account the effects of self-shielding of the baggage and radiation attenuation on the projection data, thereby ensuring high image quality and reducing manufacturing costs.

[0030] According to some embodiments, the radiation source modules are distributed multi-point sources, and the plurality of radiation source modules surround the scanning region and form a non-enclosed structure that is open to the left or right side of the scanning region.

[0031] According to some embodiments, each of the plurality of radiation source modules is a linearly distributed multi-point source, and the plurality of linearly distributed multi-point sources are respectively arranged above, below, and on the left or right side of the scanning region to form a non-closed structure that is open to the left or right side of the scanning region, and ends of the plurality of linearly distributed multi-point sources are directly connected or spaced apart.

[0032] According to some embodiments, the plurality of radiation source modules includes a plurality of first distributed multi-point sources and a plurality of second distributed multi-point sources, wherein the plurality of first distributed multi-point sources and the plurality of second distributed multi-point sources are alternately arranged, and are directly connected end to end or spaced apart.

[0033] According to some embodiments, the first distributed multi-point source is a linear distributed multi-point source and the second distributed multi-point source is a linear distributed multi-point source or an arc-shaped distributed multi-point source having a length shorter than that of the first distributed multi-point source.

[0034] According to some embodiments, each of the plurality of radiation source modules is a single point source group, and the plurality of single point source groups are arranged at at least a top field angle, a bottom field angle, a left field angle or a right field angle and at least some corner oblique field angles of the scanning area, and each single point source group includes at least two single point sources.

[0035] According to some embodiments, each radiation source module has a separate cavity for housing a respective radiation generating device.

[0036] According to some embodiments, the cavity of each radiation source module includes a separate vacuum cavity for accommodating multiple target points.

[0037] According to some embodiments, the spacing between target points within each radiation source module is smaller than the spacing between target points at the ends of adjacent radiation source modules.

[0038] According to some embodiments, the individual cavity of each radiation source module is provided with a mounting and positioning structure for mounting and positioning the radiation source module and for rotating the radiation source module to adjust the beam output angle of the radiation beam.

[0039] According to some embodiments, each detector group is a detector array including multiple detector units, and the multiple detector groups are arranged in a closed square, rectangular, polygonal, or elliptical structure surrounding the scanning area.

[0040] According to some embodiments, each detector group is a linear detector array, and the detector includes four linear detector arrays, which are arranged on four sides of the scanning area, above, below, left, and right, forming a rectangular or square structure.

[0041] According to some embodiments, each detector group is a linear detector array, and the detectors include a plurality of first linear detector arrays and a plurality of second linear detector arrays, the second linear detector arrays being shorter than the first linear detector arrays, and the plurality of first linear detector arrays and the plurality of second linear detector arrays being alternately arranged around the scanning region to form a polygonal structure.

[0042] According to some embodiments, each detector group of detectors is independently detachable from the others.

[0043] According to some embodiments, the detector groups above and below the scanning region and at the opening of the radiation source structure are configured to be attached and detached by moving perpendicular to the transport direction of the subject, and the detector groups on the opposite side of the opening of the radiation source structure are configured to be attached and detached by moving along the transport direction of the subject.

[0044] According to some embodiments, each detector group of the detectors comprises a detector arm, the radiation scanning device comprises a support frame fixed to a mounting base of the radiation scanning device, and the detector groups are attached to or detached from the support frame via the detector arms.

[0045] According to some embodiments, each detector group of detectors is configured to avoid the radiation beam of the radiation source module on the same side and to receive radiation of all remaining radiation source modules on the other side except the radiation source module on the same side.

[0046] According to some embodiments, each detector unit of the detector group includes a detector crystal for receiving radiation transmitted through the subject during scanning, the detector crystal being positioned at an end of the detector unit along the subject transport direction and adjacent to the radiation beam edge of the radiation source module on the same side in the subject transport direction but not blocking the radiation beam.

[0047] According to some embodiments, each radiation source module of the radiation source is arranged such that the radiation beam avoids the detector group on the same side and illuminates the detector crystals of the detector group on the opposite side.

[0048] According to some embodiments, each radiation source module is configured to rotate about a target axis such that a central position of the radiation beam illuminates a detector crystal of an opposing detector bank.

[0049] According to some embodiments, the radiation scanning device further comprises an image processing module arranged to perform data compensation and / or reconstruction image restoration for missing projection data at the ends of the radiation source module to obtain a complete reconstructed image.

[0050] According to some embodiments, the image processing module is configured to perform image reconstruction by an iterative method, an image region inpainting method or a combination of both.

[0051] In a third aspect, an embodiment of the present application further provides a radiation scanning device comprising: a transmission device for transporting an object to pass through a scanning region of the radiation scanning device; a radiation source including a plurality of radiation source modules, each including at least one radiation source point for emitting a radiation beam, the plurality of radiation source modules being arranged around the scanning region in a non-enclosed structure opening to one side of the scanning region when viewed along the transport direction of the object; and a detector for detecting radiation that has passed through the object during scanning, the detector including a plurality of detector groups, wherein ends of the plurality of detector groups are connected to each other when viewed along the transport direction of the object and the plurality of detector groups are arranged around the scanning region in a non-enclosed structure opening to one side of the scanning region, the openings of the non-enclosed structure of the radiation source and the openings of the non-enclosed structure of the detector are arranged opposite each other, the plurality of detector groups of the detector are fixed in the same plane perpendicular to the transport direction of the object, and the plurality of radiation source modules of the radiation source are arranged in a plurality of different planes perpendicular to the transport direction of the object.

[0052] In the radiation scanning device of this embodiment, the radiation source and the detector both surround the scanning area on only three sides, and compared to a case in which the scanning area is surrounded on four sides (which may be one or two of the radiation source and the detector), sufficient data can be acquired to perform image reconstruction, thereby reducing the cost and weight of the device and providing a lightweight radiation scanning device.

[0053] According to some embodiments, a radiation source module, the radiation source of which is located on the open side of the non-enclosed structure of the detector, and a plurality of detector groups of the detector are fixed in the same plane perpendicular to the transport direction of the object, and other radiation source modules of the radiation source are fixed in other planes perpendicular to the transport direction of the object.

[0054] According to some embodiments, other radiation source modules of the radiation source are fixed in other coplanar planes perpendicular to the transport direction of the object.

[0055] According to some embodiments, the radiation source modules are individually detachable from one another.

[0056] According to some embodiments, each of the plurality of radiation source modules is a distributed multi-point source, and when viewed along the transport direction of the object, the plurality of distributed multi-point sources are respectively arranged on three sides of the scanning area, surrounding the scanning area and forming a non-enclosed structure with one side open.

[0057] According to some embodiments, the distributed multi-point source forms a straight line, an arc line, a polygonal line, or any combination thereof, so that the radiation sources form a right-angled rectangular, rounded rectangular, polygonal, or elliptical structure opening on one side of the scanning region when viewed from the transport direction of the subject.

[0058] According to some embodiments, each of the plurality of radiation source modules is a group of single point sources, each group of single point sources including at least two single point sources.

[0059] According to some embodiments, each radiation source module has a separate cavity for housing a respective radiation generating device.

[0060] According to some embodiments, the cavity of each radiation source module includes a separate vacuum cavity for accommodating multiple target points.

[0061] According to some embodiments, the spacing between target points within each radiation source module is smaller than the spacing between target points at the ends of adjacent radiation source modules.

[0062] According to some embodiments, the individual cavity of each radiation source module is provided with a mounting and positioning structure for mounting and positioning the radiation source module and for rotating the radiation source module to adjust the beam output angle of the radiation beam.

[0063] According to some embodiments, each detector group is a detector array including a plurality of detector units, and the detector array includes a linear detector array, an arc detector array, or a combination thereof.

[0064] According to some embodiments, each detector group is a linear detector array, and the detector includes three linear detector arrays, each of which is arranged on three sides of the scanning area, forming a rectangular or square structure with an opening on one side of the scanning area.

[0065] According to some embodiments, each detector group is a linear detector array, and the detectors include a plurality of first linear detector arrays and a plurality of second linear detector arrays, the second linear detector arrays being shorter than the first linear detector arrays, and the plurality of first linear detector arrays and the plurality of second linear detector arrays being alternately arranged around the scanning area to form a polygonal structure that is open on one side of the scanning area.

[0066] According to some embodiments, each detector group of detectors is independently detachable from the others.

[0067] According to some embodiments, the detector group of detectors is configured to be attached and detached by moving perpendicular or parallel to the direction of transport of the subject.

[0068] According to some embodiments, each detector group of the detectors comprises a detector arm, the radiation scanning device comprises a support frame fixed to a mounting base of the radiation scanning device, and the detector groups are attached to or detached from the support frame via the detector arms.

[0069] According to some embodiments, when viewed in the transport direction of the subject, the detector is arranged between the radiation source and the scanning region, and along the transport direction of the subject, other radiation source modules at least partially overlap with detector groups on the same side.

[0070] According to some embodiments, the detector group on the same side as the other radiation source modules of the detector is configured to avoid the radiation beam of the radiation source module on the same side and to receive radiation of all remaining radiation source modules on the other side except for the radiation source module on the same side.

[0071] According to some embodiments, each detector unit of the detector group includes a detector crystal for receiving radiation transmitted through the subject during scanning, the detector crystal being arranged at an end of the detector unit along the transport direction of the subject, and the detector crystal of the detector group on the same side as the other radiation source modules of the detector being arranged adjacent to the radiation beam edge of the radiation source module on the same side in the transport direction of the subject but not blocking the radiation beam.

[0072] According to some embodiments, the other radiation source modules of the radiation source are arranged such that the radiation beam avoids the detector group on the same side and illuminates the detector crystals of the detector group on the opposite side.

[0073] According to some embodiments, the other radiation source module is configured to rotate about the target axis such that the central position of the radiation beam illuminates the detector crystal of the opposite detector bank.

[0074] According to some embodiments, the radiation scanning device further comprises an image processing module arranged to perform data compensation and / or reconstruction image restoration for missing projection data at the ends of the radiation source module to obtain a complete reconstructed image.

[0075] According to some embodiments, the image processing module is configured to perform image reconstruction by an iterative method, an image region inpainting method or a combination of both.

[0076] In a fourth aspect, an embodiment of the present application provides a mounting and positioning structure for a radiation source of a radiation scanning device, the radiation scanning device comprising: a radiation source and a fixedly installed support frame; the mounting and positioning structure comprises a main body, the main body being fixedly connected to the radiation source and the support frame, thereby allowing the radiation source to be fixedly mounted to the support frame by the main body; the mounting and positioning structure further comprises a moving device, a first positioning device, a lifting device and a second positioning device, the radiation source being moved to a predetermined mounting position in a first plane by the moving device, the first positioning device being used to position the radiation source in the first plane, the lifting device being used to adjust the position of the radiation source along a first direction, the first direction being perpendicular to the first plane, and the second positioning device being used to fix the position of the radiation source in the first direction.

[0077] By using the mounting and positioning structure of the above embodiment, each radiation source module of the radiation source can be individually attached and detached, and the beam emission angle of the radiation source module can also be adjusted.

[0078] According to some embodiments, the moving device includes rollers provided at both ends along the longitudinal direction of the radiation source.

[0079] According to some embodiments, the first positioning device includes a first positioning pin and a first pin hole corresponding to the first positioning pin provided on the main body and the support frame.

[0080] According to some embodiments, the lifting device is provided at both ends along the longitudinal direction of the radiation source, the lifting device at one end being formed as a liftable roller and the lifting device at the other end being formed as a lift screw jack.

[0081] According to some embodiments, the second positioning device is formed as a positioning block, which is placed below the main body after the radiation source has been adjusted to a predetermined position along the first direction by the lifting device.

[0082] According to some embodiments, the mounting and positioning structure further includes an adjustment device for rotating the radiation source along a predetermined axis to adjust the beam output angle of the radiation source.

[0083] According to some embodiments, the radiation source is provided with a mounting shaft, the main body is provided with a corresponding axial hole, the main body is attached to the mounting shaft of the radiation source through the axial hole, the positioning mounting structure further includes a positioning member and a fastener, the main body is positioned relative to the radiation source by engagement of the positioning member with the axial hole and the mounting shaft, and is fixedly connected to the radiation source by the fastener, and the adjustment device includes a rotation drive device, which can rotate the radiation source around the mounting shaft when the positioning member and the fastener are loosened.

[0084] According to some embodiments, the rotation drive device includes an adjustment block fixed to the radiation source and a screw jack abutting against the adjustment block provided on the main body, and the screw jack can be rotated to move the adjustment block, thereby rotating the radiation source.

[0085] According to some embodiments, the positioning member includes a second positioning pin and a corresponding second pin hole formed in the body and the radiation source, and the fastener includes a fixing bolt and a corresponding screw hole formed in the body and the radiation source.

[0086] According to some embodiments, there is further provided a radiation scanning device including a radiation source and a fixedly mounted support frame, wherein the radiation source is fixedly attached to the support frame via the mounting and locating structure of any of the above embodiments.

[0087] According to some embodiments, the radiation scanning device adjusts the beam emission angle of the radiation source by rotating the radiation source using the mounting and positioning structure.

[0088] In a fifth aspect, an embodiment of the present application further provides a mounting and fixing structure for a detector used in a radiation scanning device, the radiation scanning device including a detector and a fixedly installed support frame, the detector including one or more detector groups, the detector groups being fixedly attached to the support frame or detached from the support frame via the mounting and fixing structure, the mounting and fixing structure including a first mounting portion, a second mounting portion and a fixing device, the first mounting portion being fixedly installed to the detector group, the second mounting portion being fixedly installed to the support frame and engaging with the first mounting portion so as to be linearly movable, the detector group being movable along the second mounting portion to a predetermined mounting position with the first mounting portion and the second mounting portion engaged with each other, the fixing device being provided on one side along the width direction of the detector group and being used to fix the detector group to an attachment reference surface on the support frame.

[0089] By utilizing the mounting and fixing structure according to the above embodiment, each detector group of detectors can be individually detached and placed inside the radiation source module, and can be detached and maintained without removing the radiation source module, thereby improving the convenience of attaching, detaching, and maintaining the detector groups.

[0090] According to some embodiments, the second mounting portion is further configured to support the detector cluster in a predetermined mounting position when engaged with the first mounting portion.

[0091] According to some embodiments, the first mounting portion includes a slider that extends along the length of the detector cluster, and the second mounting portion includes a fixed guide rail that engages the slider.

[0092] According to some embodiments, the fixing device includes a fastener and a positioning member provided on the support frame, the end face of the positioning member away from the support frame being formed as an attachment reference surface for abutting against a surface on one side along the width direction of the detector group, and the fastener passes through the positioning member to clamp the detector group against the end face of the positioning member.

[0093] According to some embodiments, the sliders are provided on opposite sides of the detector group in the width direction, and have inner extensions extending inward from the edges of the detector group on opposite sides facing each other in the width direction, and the fixed guide rail includes outer extensions extending outward on opposite sides facing each other in the width direction, and when the first mounting portion and the second mounting portion are engaged, the inner extensions of the sliders are located above the outer extensions of the fixed guide rails, and the two are arranged in contact and overlapping relation, so that the detector group is suspended from the fixed guide rails.

[0094] According to some embodiments, a fixed guide rail supports the slider below the slider.

[0095] According to some embodiments, the first mounting portion is formed as a slide groove extending along the width direction of the detector group, and the second mounting portion is formed as a slide rod that engages with the slide groove.

[0096] According to some embodiments, a protrusion is formed at one end of the slide rod close to the support frame, and the surface of the protrusion facing the detector group is formed as an attachment reference surface for abutting against the surface on the other side along the width direction of the detector group.

[0097] According to some embodiments, the fixing device is provided at the other end of the slide rod opposite the protrusion, and is arranged to abut against the protrusion on both sides of the detector group in the width direction.

[0098] According to some embodiments, the fixing device includes a positioning sleeve and a fastener, the positioning sleeve being fitted onto the other end of the slide rod and abutting one side along the width direction of the detector, and the fastener being used to fix the positioning sleeve to the other end of the slide rod.

[0099] According to some embodiments, the second mounting portion includes two slide rods, and the first mounting portion includes two slide grooves formed at both ends along the longitudinal direction of the detector group, and the two slide rods and the two slide grooves respectively engage with each other to position the detector group in a predetermined mounting position.

[0100] According to some embodiments, the first mounting portion is formed as a fixed block fixed to one side along the width direction of the detector group, the fixed block having an opening on one side facing the thickness direction of the detector group, and the second mounting portion is formed as a cantilever portion fixed to the support frame, and an extension portion is provided at the end of the cantilever portion away from the support frame that engages with the opening in the fixed block so as to be able to move linearly.

[0101] According to some embodiments, the fixing device includes a fixture and a fastener provided on the support frame, the end face of the fixture away from the support frame being formed as an attachment reference surface for abutting against one side surface along the width direction of the detector group, and the fastener being used to fasten the detector group to the end face of the fixture.

[0102] According to some embodiments, when the first mounting portion and the second mounting portion are engaged, the cantilever portion supports the detector group in a predetermined mounting position via the fixing block.

[0103] According to some embodiments, there is further provided a radiation scanning device including a detector and a fixedly installed support frame, wherein the detector includes one or more detector groups, and the detector groups are attached and fixed to the support frame by the attachment and fixation structure of any of the above embodiments, or are detached from the support frame.

[0104] According to some embodiments, the width direction of the detector group is parallel to the transport direction of the object, and the length and thickness directions of the detector group are perpendicular to the transport direction of the object, which is the direction in which the object is transported through the scanning area of ​​the radiation scanning device.

[0105] According to some embodiments, when the detector includes multiple detector groups, the mounting reference planes for each of the multiple detector groups lie in the same plane perpendicular to the transport direction of the object.

[0106] According to some embodiments, the direction of linear movement of the first mounting part relative to the second mounting part is parallel or perpendicular to the direction of transport of the subject.

[0107] Other features and technical advantages of the present application will become more apparent from the accompanying drawings and detailed description of other embodiments. [Brief explanation of the drawings]

[0108] In order to more clearly explain the technical solutions in the embodiments of the present application or related technologies, the following will briefly describe the drawings that need to be used in the description of the embodiments or related technologies. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings based on these drawings without any creative work.

[0109] [Figure 1] 1 shows a structural schematic diagram of a radiation scanning device according to some embodiments of the present application; [Figure 2] FIG. 2 is a specific structural schematic diagram of a radiation source and a detector of the radiation scanning device shown in FIG. [Figure 3] 1 shows a schematic diagram of a radiation beam shape of a radiation source according to some embodiments of the present application; [Figure 4] 1 shows a schematic diagram of a distribution of radiation sources shown in the form of target points according to some embodiments of the present application. [Figure 5] 1 is a schematic diagram of a mounting and positioning structure for a radiation source module according to some embodiments of the present application; [Figure 6] 1 is a schematic diagram of a distribution of detectors according to some embodiments of the present application; [Figure 7] 1 is a structural schematic diagram of a linear detector array according to some embodiments of the present application; [Figure 8] 1 is a schematic structural diagram of a detector unit according to some embodiments of the present application; [Figure 9] 1 is a schematic diagram of a mounting and fixing structure for a detector group according to some embodiments of the present application; [Figure 10]1 is a schematic diagram of a radiation source module and a corresponding relationship between the radiation source module and a detector group that receives the radiation, according to some embodiments of the present application; [Figure 11] 2 is a schematic cross-sectional view of the radiation scanning device shown in FIG. 1 along a center line in a transport direction of a subject according to some embodiments of the present application; FIG. [Figure 12] FIG. 1 is a top view schematic diagram of a detector and radiation source layout according to some embodiments of the present application. [Figure 13] 1 is a schematic diagram of a detector and radiation source combination according to some embodiments of the present application; [Figure 14] FIG. 14 is a schematic exploded view of the detector group in the detector and radiation source combination shown in FIG. 13 according to some embodiments of the present application; [Figure 15] 1 illustrates a suitable mounting structure for a detector cluster according to some embodiments of the present application. [Figure 16] 10 is a mounting structure suitable for a detector group according to some other embodiments of the present application. [Figure 17] 10 is a mounting and fixing structure suitable for a detector group according to yet another embodiment of the present application. [Figure 18] 1 is a schematic diagram of the arrangement of radiation sources and detectors in a radiation scanning device according to some embodiments of the present application; [Figure 19] 1 is a perspective schematic diagram of a layout of radiation sources and detectors in a radiation scanning device according to some embodiments of the present application; [Figure 20] FIG. 20 is a side view of the layout of the radiation sources and detectors of the radiation scanning device shown in FIG. 19 as viewed from the Z-axis direction. [Figure 21] FIG. 20 is a schematic top view showing the layout of radiation sources and detectors of the radiation scanning device shown in FIG. [Figure 22] 1 is a schematic diagram of a single point source distribution of a radiation source of a radiation scanning device according to some embodiments of the present application; [Figure 23] 1 is a structural schematic diagram of a detector of a radiation scanning device according to some embodiments of the present application; [Figure 24] 1 is a schematic diagram of a mounting and dismounting direction of a detector according to some embodiments of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0110] The following describes in detail the features and exemplary embodiments of each aspect of the present application. In order to more clearly understand the objectives, technical solutions, and advantages of the present application, the present application will be described in more detail below with reference to the drawings and specific examples. It should be understood that the specific examples described herein are intended only to interpret the present application and do not limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the examples is provided merely to illustrate the present application and to provide a better understanding of the present application.

[0111] It should be noted that, in this specification, relational terms such as "first" and "second" are merely used to distinguish one entity or operation from another and do not necessarily require or imply that such an actual relationship or order exists between those entities or operations. Furthermore, the terms "comprises," "having," or any other variations thereof are intended to cover a non-exclusive inclusion, whereby a process, method, article, or apparatus that includes a set of elements not only includes those elements, but also includes other elements not expressly listed or that are inherent in such process, method, article, or apparatus. Absent more limitations, elements qualified by the phrase "comprises" do not exclude the presence of other identical elements in a process, method, article, or apparatus that includes the elements.

[0112] The static CT (distributed multi-point source) or multiple field of view (single point source) device in the background art section above typically includes multiple planar lightwave circuits, which are arranged along the length of the device (i.e., the transport direction of the subject). This arrangement results in a long optical path coverage area for the entire static CT (distributed multi-point source) or multiple field of view (single point source) device, which is unfavorable for reducing the overall length and weight of the device.

[0113] Furthermore, in the device arranged as described above, one detector array corresponds to only one set of distributed multi-point sources or one single-point source, which increases the number of detector arrays in the entire device, which is detrimental to reducing the cost of the entire device.

[0114] In an apparatus arranged as described above, concentrating all of the radiation sources in a single annular or rectangular sealed cavity increases the complexity of the apparatus and reduces the reliability of the apparatus, particularly for an apparatus that needs to maintain a high degree of vacuum, and also makes it difficult to maintain the radiation sources.

[0115] In static CT with the above-mentioned double-ring structure design, the arrangement of the radiation source ring and the detector ring can ensure that a single detector can be shared by multiple radiation sources, but it still leaves unresolved the problems of poor reliability and maintainability caused by concentrating the radiation sources in a single annular sealed cavity. At the same time, if the radiation source ring and the detector ring are positioned too close together, the detector can only be replaced or maintained from inside the ring, making the detector difficult to maintain. If the distance between the radiation source ring and the detector ring is sufficiently large, the detector can be replaced or maintained from outside the ring. However, this arrangement increases the coverage area of ​​the optical path and increases the length of the device. Furthermore, an inclination angle exists between the center of the radiation beam and the surface of the detector crystal, causing the radiation beam to be obliquely irradiated onto the detector crystal, affecting image quality.

[0116] In order to solve the various technical problems described above, an embodiment of the present application provides a radiation scanning device, which includes: a transmission device for transporting a subject through a scanning area of ​​the radiation scanning device; a radiation source including a plurality of radiation source modules, each including at least one radiation source point for emitting a radiation beam, the plurality of radiation source modules being arranged around the scanning area and fixed in a plane perpendicular to a transport direction of the subject; and a detector for detecting radiation transmitted through the subject during scanning, the detector including a plurality of detector groups whose ends are connected to each other so as to be arranged around the scanning area and fixed in a plane perpendicular to the transport direction of the subject, the detector being located between the radiation source and the scanning area along a direction perpendicular to the transport direction of the subject, the radiation source and the detector being arranged so as to at least partially overlap along the transport direction of the subject, and the plurality of radiation source modules being individually attachable and detachable from each other.

[0117] According to the radiation scanning device of the present invention, the radiation source is formed by arranging a plurality of radiation source modules around the scanning region, and the plurality of radiation source modules are individually detachable from each other, i.e., each radiation source module has an individual cavity for accommodating a respective radiation generating device. Compared with a radiation source that integrally surrounds the scanning region, the radiation source formed by combining a plurality of radiation source modules of the present invention can reduce the size of the housing of a single radiation source module and the volume of the internal vacuum cavity, so that the single radiation source module has a small volume and a light weight, thereby facilitating the detachment and installation of the radiation source. In addition, since multiple target points of a single radiation source module can adopt individual vacuum cavities, the risk of ignition in the cavity during maintenance of the radiation source can be reduced.

[0118] According to some embodiments of the present application, the individual cavity of each radiation source module is provided with an attachment and positioning structure for fixing the radiation source module at a corresponding position in the radiation scanning device, for example, for positioning the radiation source module with respect to the support frame and for rotating the radiation source module around a predetermined axis to adjust the beam output angle of the radiation beam. The attachment and positioning structure can also determine the position of each radiation source module, thereby ensuring that the multiple radiation source modules of the radiation source are positioned in a plane (e.g., the same plane or different planes) perpendicular to the transport direction of the object after being attached.

[0119] Here, optionally, the radiation source modules may be distributed multi-point sources, surrounding the scanning region to form a ring structure, such as a rectangular ring, a polygonal ring, or an elliptical ring. Specifically, the radiation source modules may be linearly distributed multi-point sources, each of which may include multiple target points, and the multiple radiation source modules may be distributed above, below, left, and right of the scanning region to form a rectangular ring surrounding the scanning region. The ends of the radiation source modules may be directly connected to form a continuous rectangular ring, or may be spaced apart by a certain gap to form a discontinuous rectangular ring. According to other embodiments, the radiation source may further include a plurality of short linearly distributed multi-point sources, alternating with a plurality of long linearly distributed multi-point sources, and connected end-to-end directly to form a continuous polygonal arrangement, or spaced end-to-end to form a discontinuous polygonal arrangement; or the radiation source may further include a plurality of short arc-shaped distributed multi-point sources, alternating with a plurality of long linearly distributed multi-point sources, and connected end-to-end directly to form a continuous rounded rectangular arrangement, or spaced end-to-end to form a discontinuous rounded rectangular arrangement; or the radiation source may further include other numbers, shapes and / or lengths of radiation source modules to form other polygonal or elliptical structures, etc.

[0120] In addition, each radiation source module of the radiation source may be a single point source group, and each single point source group includes at least two single point sources, and optionally, the multiple single point source groups of the radiation source are distributed at a bottom field angle, left and right side field angles, a top field angle and a corner oblique field angle surrounding the scanning area to form a multiple field angle arrangement.

[0121] In other embodiments, the radiation source modules may be arranged to surround the scanning area on only three sides, such as the upper, left, and right sides, or the upper, lower, and left or right sides (it should be noted that in this specification, the upper, lower, left, and right sides of the scanning area refer to the upper, lower, left, and right sides when viewing the scanning area along the transport direction of the subject). Accordingly, the radiation source may be arranged in a non-closed structure that is open on one side surrounding the scanning area, such as a rectangular structure, a polygonal structure, or an elliptical structure that is open on one side. More specifically, the radiation source may be a discontinuous or continuous rectangular structure, a continuous polygonal structure, a continuous rounded rectangle, a discontinuous polygonal or discontinuous rounded rectangle structure, and other polygonal and elliptical structures that are open on one side surrounding the scanning area. If the radiation source is a single point source, it is accordingly not necessary to install a single point source on one side of the scanning area.

[0122] In the radiation scanning device of the present application, the detector has a structure surrounding the scanning area formed by connecting the ends of multiple detector groups. Optionally, depending on the arrangement of the various radiation sources, the detector may have a structure surrounding the scanning area on all four sides (top, bottom, left, and right), or a non-closed structure opening to one side of the scanning area, such as a rectangular structure, polygonal structure, or elliptical structure opening to one side of the scanning area (more specifically, a continuous or discontinuous rectangular structure opening to one side surrounding the scanning area, a continuous or discontinuous polygonal structure, a continuous or discontinuous rounded rectangular structure, a single-point source with multiple viewing angles, etc.), and the multiple detector groups are arranged as a closed rectangular structure, square structure, polygonal structure, or elliptical structure surrounding the scanning area. Specifically, each detector group may include multiple detector units and a detector arm, and the multiple detector units are linearly arranged on the detector arm. The detector may include four detector groups arranged on the four sides of the scanning area, respectively, to form a closed rectangular or square structure surrounding the scanning area. The detector may also include a plurality of long detector groups and a plurality of short detector groups to form a closed polygonal structure surrounding the scanning area. Alternatively, in accordance with the non-closed structure of the radiation source that is open on one side of the scanning area, the multiple detector groups of the detector may be arranged in a non-closed structure that is open on one side surrounding the scanning area, such as a rectangular, square, polygonal, or elliptical structure that is open on one side.

[0123] According to some embodiments, the multiple detector groups of the detector are individually detachable. This allows each detector group to be detached and attached individually, facilitating maintenance of the detectors. Alternatively, the multiple detector groups of the detector may be configured to be attached and detached by moving them in the transport direction of the subject. Alternatively, when the radiation source is arranged in a non-enclosed structure surrounding the scanning region and having an opening on one side, some of the multiple detector groups of the detector may be attached and detached by moving them in a direction perpendicular to the transport direction of the subject, and other parts may be attached and detached by moving them in the transport direction of the subject. This allows the detector groups to be attached and detached or maintained without removing the radiation source module, even when the detectors are arranged inside the radiation source in a direction perpendicular to the transport direction of the subject, thereby improving the workability of attaching, detaching, and maintaining the detectors.

[0124] In addition, according to some embodiments, the attachment and detachment of the detector group can be achieved by linear movement engagement, such as linear sliding or linear rolling engagement, between the detector arm of the detector group and an attachment portion of the radiation scanning device, for example, on the support frame of the radiation scanning device, which may be, for example, a slider guide rail engagement provided between the detector arm and the support frame, or an engagement between a linear ball bearing and a cylindrical shaft.

[0125] According to some embodiments, each detector unit of a detector group includes a detector crystal for receiving radiation, and the detector units of each detector group are arranged on the detector arm so that the detector crystals face the same direction. As described above, in the present application, each detector group is located in a plane perpendicular to the transport direction of the object, and particularly, is located in the same plane, which specifically means that the detector crystals of each detector group are located in the same plane perpendicular to the transport direction of the object. According to other embodiments, each detector group may be located in a different plane perpendicular to the transport direction of the object.

[0126] In the radiation scanning device according to the present application, the radiation source according to any one of the above embodiments is combined with the detector according to any one of the above embodiments, and in the combined state, each radiation source module of the radiation source is located in a plane (in one or more planes) perpendicular to the transport direction of the object, each detector group of the detector is located in another plane (particularly in the same plane) perpendicular to the transport direction of the object, the detectors are located inside the radiation source in a direction perpendicular to the transport direction, and the radiation source and the detector are arranged to at least partially overlap in the transport direction of the object. By at least partially overlapping the radiation source and the detector in the transport direction of the object, the arrangement length of the radiation source and the detector can be reduced, which is advantageous for reducing the overall length of the radiation scanning system.

[0127] In some embodiments, each detector group of the detectors is positioned so as not to block the radiation beam of the radiation source module on the same side, and can receive radiation from each radiation source module on the remaining side, thereby allowing different radiation source modules to share the same detector group and reducing the total number of detectors.

[0128] In some embodiments, the detector crystals of each detector group of the detectors are arranged at an end of the detector unit along the transport direction of the object, adjacent to the edge of the radiation beam of the radiation source module on the same side in the transport direction of the object, but not blocking the radiation beam of the radiation source module on the same side, thereby making it possible to minimize the cover length of the optical path between the radiation source and the detector, and further reducing the length of the apparatus.

[0129] In some embodiments, each radiation source module is arranged so that the radiation beam avoids the detector group on the same side and irradiates the detector crystal of the detector group on the opposite side. More specifically, the radiation source module can be rotated about a predetermined axis, such as a target axis, to adjust the beam emission angle of the radiation beam (for example, by using the mounting and positioning structure of the radiation source module), so that the center position of the radiation beam from the radiation source module can be irradiated onto the detector crystal of the detector group on the opposite side. Since the detector crystal of the detector is located at the end position of the detector unit in the transport direction of the subject and is located adjacent to the edge of the radiation beam of the radiation source on the same side, the radiation source module only needs to be rotated by a small angle so that the center position of the radiation beam can be irradiated onto the detector crystal, thereby minimizing the adverse effect on imaging caused by the radiation beam being obliquely incident on the surface of the detector crystal. The adjustment of the beam emission angle of the radiation source can also be achieved by other appropriate methods, such as setting the aperture direction of the radiation source module or adjusting the collimator.

[0130] According to some embodiments, the image processing module of the radiation scanning device of the present application is configured to have a data compensation function that can compensate for missing data in the field of view and / or perform restoration on the reconstructed image to improve image quality. Specifically, the image processing module is configured to perform image reconstruction using an iterative method, an image region restoration method, or a combination of both, thereby compensating for missing projection data due to an increase in the distance between target points at the ends of adjacent radiation source modules, and improving the quality of the reconstructed image.

[0131] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0132] FIG. 1 is a schematic diagram of a radiation scanning device according to some embodiments of the present application. The radiation scanning device shown in FIG. 1 includes a transmission device 1, a passageway 2, a radiation source 3, a detector 4, and a support frame 5. The transmission device 1 is used to transport a subject 6 through a scanning area of ​​the radiation scanning device, which is defined by the radiation source 3 and the detector 4. The subject 6 enters the passageway 2 from an opening at one end of the passageway 2 and leaves the opening at the other end of the passageway 2 by being driven by the transmission device 1. The passageway 2 shields radiation from the radiation source 3 from the external environment, thereby avoiding radiation injury to people near the device and limiting the volume of the subject 6 that enters the passageway 2. The radiation source 3 is fixed to the support frame 5 outside the passageway 2 so as to emit a radiation beam for irradiating the subject 6 during scanning. The detector 4 is also fixed to the support frame 5 outside the passageway 2 and is used to detect radiation that has passed through the subject 6 during scanning. The support frame 5 is used to support and fix devices such as the transmission device 1, the passage 2, the radiation source 3, and the detector 4, and is fixed to the ground. Note that the radiation source 3 and the detector 4 are both located outside the passage 2, but an escape area is provided in the passage 2 in the scanning area so that the radiation beam of the radiation source 3 is not blocked and the detector 4 does not interfere with receiving radiation.

[0133] The radiation scanning device according to the embodiment of the present application may further include a control device that controls the operation of each component of the radiation scanning device, for example, the emission of radiation from the radiation source 3 and the data output from the detector 4. The control device may further include an image processing module that performs image reconstruction based on the information output from the detector 4 to obtain a scanned image of the subject 6.

[0134] The transmission device 1 may be, for example, a transmission belt, and the subject 6 may be, for example, various items such as parcels and luggage that require security checks.

[0135] The radiation source 3 may include multiple radiation source modules, each of which is arranged around the scanning region and located in a plane perpendicular to the transport direction of the object 6. The radiation source modules may be arranged in the same plane perpendicular to the transport direction of the object 6 or in different planes. In this embodiment, the radiation source modules are arranged in the same plane perpendicular to the transport direction of the object 6 (specifically, the radiation apertures of each radiation source module are arranged in the same plane perpendicular to the transport direction of the object 6), but the present invention is also applicable to the case where the radiation source modules are arranged in different planes. FIG. 1 shows the traveling direction Z of the object 6, and the transport direction of the object 6 (hereinafter sometimes abbreviated as the transport direction or the Z direction) is defined as the traveling direction of the object 6 and includes the opposite direction to the traveling direction. FIG. 1 also shows an XYZ coordinate system, which can be used as a reference coordinate system to describe the positions of components in the radiation scanning device. The description of these positions is intended to clearly explain the principles of the present application and is not intended to be limiting. The traveling direction Z of the subject 6 is the same as the Z direction of this XYZ coordinate system.

[0136] According to some embodiments, each radiation source module of the radiation source 3 of the radiation scanning device according to the embodiments of the present application may be a distributed multi-point source, and the multiple radiation source modules may be arranged in a rectangular structure, a polygonal structure, an elliptical structure, etc. surrounding the scanning area, and part of the structure is located below the transmission device 1 so as to completely surround the transmission device 1.

[0137] Specifically, as a distributed multi-point source, each radiation source module can have multiple target points, and each target point of each radiation source module can generate a radiation beam independently. Each target point can generate a radiation beam in a predetermined time sequence under the control of the control device. The radiation beam can be a fan beam with an opening angle A, as shown in Figure 3. Of course, the shape of the radiation beam is not limited to a fan beam, and can be a radiation beam of other shapes such as a cone beam or a parallel beam, and can be specifically configured as needed.

[0138] The specific arrangement of the radiation source 3 is as follows. Figure 2 shows a structural schematic diagram of a radiation source and detector according to some embodiments, in which multiple radiation source modules of the radiation source 3 are arranged in a rectangular structure surrounding the scanning area. Specifically, the radiation source 3 includes four radiation source modules 31, 32, 33, and 34, each of which is a linearly distributed multi-point source (i.e., multiple target points are arranged in a line). The four radiation source modules 31, 32, 33, and 34 are respectively arranged above, below, left, and right of the scanning area, forming a rectangular structure surrounding the scanning area. Since there is a certain distance between the ends of the radiation source modules 31, 32, 33, and 34, they form a discontinuous rectangular structure (as shown in Figure 4(a) , the target points are similarly arranged in a discontinuous rectangle).

[0139] The arrangement of the radiation source 3 is not limited to the embodiments shown in Figures 2 and 4(a) and may include several other alternative arrangements. For example, the ends of the radiation source modules 31, 32, 33, and 34 can be directly connected to each other, so that the radiation source 3 is arranged around the scanning area in a continuous rectangular structure (as shown in Figure 4(b) , the target points are arranged in a continuous rectangular shape). Alternatively, based on the embodiment shown in Figure 2, the radiation source 3 may further include four other linearly distributed radiation source modules 35, 36, 37, and 38, which are shorter in length than the radiation source modules 31, 32, 33, and 34, are arranged alternately with the radiation source modules 31, 32, 33, and 34, and have directly connected ends, so that the radiation source 3 is arranged in a continuous polygonal structure (as shown in Figure 4(c) , the target points are arranged in a continuous polygonal shape). Alternatively, the radiation source modules 35, 36, 37, and 38 may be arc-shaped distributed radiation sources, and may be arranged alternately with the radiation source modules 31, 32, 33, and 34, with their ends directly connected, so that the radiation source 3 is arranged in a continuous rounded rectangular structure. Of course, the ends of the radiation source modules 31, 32, 33, 34, 35, 36, 37, and 38 may be spaced apart by a certain distance (not shown) so that the radiation source 3 is arranged in a discontinuous polygonal structure or a discontinuous rounded rectangular structure. Alternatively, the lengths of the radiation source modules 35, 36, 37, and 38 may be the same as or longer than the lengths of the radiation source modules 31, 32, 33, and 34, or the radiation source 3 may include other numbers (pluralities) and / or lengths of radiation source modules to form a polygonal structure different from the polygon shown in FIG. 4(c). Alternatively, the radiation source 3 may include other numbers (pluralities), lengths, and / or shapes of radiation source modules to form an elliptical structure.

[0140] In some embodiments, the radiation source modules included in the radiation source 3 are individually detachable from each other, i.e., each radiation source module has an individual cavity for accommodating a respective radiation generating device. Each radiation source module having an individual cavity means that multiple target points of each radiation source module share one individual vacuum cavity. The spacing between the multiple target points of each radiation source module within the vacuum cavity can be determined by the number of target points and the length of the cavity. According to some embodiments, the number of target points in a single radiation source module may be 192, 264, etc., and the spacing between the target points in a single radiation source module may be 4 mm, 12 mm, etc. It should be noted here that the spacing between the target points at the ends of adjacent radiation source modules is larger than the spacing between the target points within a single radiation source module, even if the ends of adjacent radiation source modules are directly connected, i.e., two individual cavities are directly connected. The fact that each radiation source module has its own cavity has the advantage that, compared to a radiation source with an integral annular cavity (i.e., all target points of the radiation source are located in the same annular vacuum cavity), the size of the housing of the single radiation source module and the volume of the internal vacuum cavity are reduced, and the volume and weight of the single radiation source module are reduced, making it convenient to attach and detach the radiation source. In addition, the use of a separate vacuum cavity for each radiation source module reduces the risk of ignition in the cavity during maintenance of the radiation source module.

[0141] According to some embodiments, each radiation source module of the radiation source 3 is provided with a mounting and positioning structure for facilitating mounting and adjustment of the radiation source module. The mounting and positioning structure allows each radiation source module of the radiation source 3 to be mounted and fixed at a predetermined position in the radiation scanning device (e.g., a specific position relative to the XYZ reference coordinate system in the radiation scanning device), ensuring, for example, that the multiple radiation source modules are positioned in the same plane perpendicular to the transport direction of the object 6. The mounting and positioning structure also allows the radiation source module to be rotated, thereby adjusting the beam emission angle of the radiation beam.

[0142] Since the radiation source modules of the radiation source 3 are located at different positions in the radiation scanning device, different mounting methods and different mounting structures may be used. For example, the radiation source modules located above and to the sides of the scanning area may be mounted in a suspended manner using an overhead travelling vehicle or other device. However, the radiation source modules located below the scanning area are not suitable for the suspended method and must be mounted in a different manner. To facilitate the mounting of such radiation source modules, embodiments of the present application provide a mounting structure that can easily mount and fix radiation source modules that are not suitable for the suspended method at predetermined positions in the radiation scanning device and also rotate the radiation source modules to adjust the beam output angle of the radiation beam. According to some embodiments, the mounting structure includes a main body that is fixedly connected to the support frame so that the radiation source modules are fixedly mounted to the support frame of the radiation scanning device and the radiation source modules via the main body. Here, the mounting and positioning structure includes a moving device that moves the radiation source module to a predetermined mounting position in a first plane (e.g., the XZ plane in Figure 1), a first positioning device that positions the radiation source module in the first plane, a lifting device that adjusts the position of the radiation source module along a first direction (e.g., the Y direction in Figure 1 that is perpendicular to the XZ plane), where the first direction is perpendicular to the first plane, and a second positioning device that fixes the position of the radiation source module in the first direction.

[0143] FIG. 5 shows a specific embodiment of the mounting and positioning structure for the radiation source module. As shown in FIG. 5, the mounting and positioning structure includes main bodies 11 and 12, which are located at both ends of the radiation source module in the longitudinal direction and fixedly connected to the radiation source module (here, the radiation source module is described as the radiation source module 33 of the radiation source 3 in FIG. 2 by way of example, but may be other suitable radiation source modules). The radiation source module 33 is fixedly mounted to the support frame 5 (not shown in FIG. 5) via the main bodies 11 and 12. The moving devices of the mounting and positioning structure are specifically rollers 13 and 14 mounted on the main bodies 11 and 12, respectively. The radiation source module 33 is moved to a predetermined mounting position in the XZ plane by being pushed by the rollers 13 and 14. Of course, the moving devices of the mounting and positioning structure are not limited to rollers. In other embodiments, the radiation source module may be moved by a sliding mechanism. For example, a linear sliding engagement may be provided between the mounting and positioning structure and the support frame 5 to move the radiation source module 33 to a predetermined mounting position.

[0144] The first positioning device includes first positioning pins 15, 16 and corresponding first pin holes (not shown) provided on the main body 11, 12 and the support frame 5 of the radiation scanning device, and after the radiation source module 33 is moved to a predetermined mounting position via the rollers 13, 14, the first positioning pins 15, 16 can be inserted into the corresponding first pin holes to position the radiation source module 33 on the XZ plane.

[0145] The lifting device includes rollers 13 provided on the main body 11, and the rollers 13 are specifically provided as liftable rollers, and further include a lift screw jack 17 provided on the main body 12, one end of which abuts against the support frame 5. By turning the lift screw jack 17, the main body 12 and the radiation source module 33 can be raised and lowered relative to the support frame 5. By adjusting the liftable rollers 13 and the lift screw jack 17, the position of the radiation source module 33 relative to the support frame 5 can be adjusted along the Y direction. The second positioning device is formed as positioning blocks 19 and 20. After adjusting the liftable rollers 13 and the lift screw jack 17 to adjust the radiation source module 33 to a predetermined position along the Y direction, the positioning blocks 19 and 20 can be placed below the main bodies 11 and 12, respectively, to fix the height of the radiation source module 33 relative to the support frame 5, and the radiation source module 33 can be positioned along the first direction Y. Optionally, the positioning block 20 below the main body 12 may be installed in a U-shape, and the lower part of the lift screw jack 17 may be located in the opening of the U-shaped positioning block 20 to prevent the two from interfering with each other. The mounting and positioning structure may further include first fixing bolts 21, 22 and corresponding first screw holes provided in the main bodies 11, 12, the positioning blocks 19, 20, and the support frame 5, and the first fixing bolts 21, 22 may be inserted into and tightened to fix the positioning blocks 19, 20 to the main bodies 11, 12 and the support frame 5, and the radiation source module 33 may be fixedly connected to the support frame 5.

[0146] According to some embodiments, the mounting and positioning structure further includes an adjusting device for rotating the radiation source module along a predetermined axis to adjust the beam emission angle thereof. According to the specific embodiment of Fig. 5, the radiation source module 33 is provided with a mounting shaft 331, and the main bodies 11 and 12 are each provided with an axial hole, and the main bodies 11 and 12 are mounted on the mounting shaft 331 through the axial hole. The mounting and positioning structure further includes second positioning pins 23 and 24, and the main bodies 11 and 12 and the radiation source module 33 are each provided with second pin holes corresponding to the second positioning pins 23 and 24. By engaging the axial holes of the main bodies 11 and 12 with the mounting shaft 331 and inserting the second positioning pins 23 and 24 into the corresponding second pin holes, the main bodies 11 and 12 can be positioned relative to the radiation source module 33. The mounting and positioning structure further includes second fixing bolts 25, 26 for fixedly connecting the main bodies 11, 12 to the radiation source module 33, and corresponding second screw holes provided in the main bodies 11, 12 and the radiation source module 33. By screwing the second fixing bolts 25, 26 into the corresponding second screw holes, the main bodies 11, 12 can be fixedly connected to the radiation source module 33. By pulling out the second positioning pins 23, 24 and loosening the second fixing bolts 25, 26, the main bodies 11, 12 can be loosened from the radiation source module 33. In this state, the adjustment device can drive the radiation source module 33 to rotate about the mounting axis 331 relative to the main bodies 11, 12.

[0147] In a specific embodiment, the adjustment device includes a rotation drive mechanism, which includes an adjustment block 27 fixed to the radiation source module 33 and a screw jack 28 provided on the main body 11 and abutting against the adjustment block 27, and the screw jack 28 can be turned to push and move the adjustment block 27 to rotate the radiation source module 33. Here, the rotation drive mechanism is provided on only one main body of the mounting and positioning structure, i.e., only one end along the longitudinal direction of the radiation source module 33. Because both ends of the radiation source module 33 are supported by the mounting shaft 331, the radiation source module 33 can be pushed and rotated at one end, and the entire radiation source module 33 can be rotated accordingly. After rotating the radiation source module 33 by a predetermined angle, the second positioning pins 23, 24 are again inserted into the corresponding second pin holes, and the second fixing bolts 25, 26 are again screwed into the corresponding second screw holes, so that the main bodies 11, 12 are fixedly connected to the radiation source module 33.

[0148] In the above embodiment, the mounting axis 331 of the radiation source module 33 can overlap with the virtual connecting line of multiple target points of the radiation source module 33, so that by rotating the radiation source module 33 around the mounting axis 331, the radiation source module 33 can be rotated around the target axis.

[0149] Furthermore, although the mounting and positioning structure of the above embodiment has been described using the radiation source module 33 of the radiation source 3 in FIG. 2 as an example, the mounting and positioning structure can be applied to the mounting, positioning, and adjustment of any suitable radiation source in a radiation scanning device. Of course, the mounting, positioning, and adjustment of the radiation source module 33 of the radiation source 3 in FIG. 2 are not limited to the mounting and positioning structure of the above embodiment, and any other suitable structure may be adopted. For example, in the embodiment shown in FIG. 5, the lifting device is realized by the elevatable roller 13 and the lift screw jack 17. However, the lifting device is not limited to the specific structure of this embodiment and may be realized as other suitable structures, such as lift screw jacks for both the two bodies. Similarly, the specific implementations of the moving device, first positioning device, second positioning device, and adjustment device are not limited to the specific structures of the above embodiment, and other suitable structures may be adopted as long as they can achieve their functions.

[0150] In the above embodiment, the radiation source module of the radiation source 3 of the radiation scanning device shown in Figure 1 is a distributed radiation source. Alternatively, the radiation source 3 may be composed of a plurality of single point source groups, each single point source group including at least two single point sources. Each single point source can individually emit a radiation beam, for example a fan beam having an opening angle A (shown in Figure 3). Each single point source of the radiation source 3 can emit radiation according to a predetermined time sequence under the control of a control device of the radiation scanning system. Figure 4(d) shows a layout of a radiation source including a plurality of single point source groups according to some embodiments. 4(d), the radiation source includes a plurality of single point source groups arranged at the bottom, left, right, top, and corner oblique viewing angles around the scanning region, where the bottom viewing angle single point source group includes three single point sources arranged at the left bottom, middle bottom, and right bottom viewing angles, respectively; the top viewing angle single point source group includes three single point sources arranged at the left top, middle top, and right top viewing angles, respectively; the left viewing angle single point source group includes two single point sources arranged at the upper left and lower left viewing angles, respectively; the right viewing angle single point source group includes two single point sources arranged at the upper right and lower right viewing angles, respectively; and the corner oblique viewing angle single point source group includes four single point sources arranged at the upper left, upper right, lower left, and lower right oblique viewing angles, respectively. According to other embodiments, each single point source group may include more single point sources. Similarly, each single point source includes a respective mounting and positioning structure that allows the single point source to be mounted and positioned to ensure that the multiple single point sources are located in the same plane perpendicular to the transport direction of the subject 6. The mounting and positioning structure is also used to rotate the single point sources to adjust the beam emission angle of the radiation of each single point source.

[0151] The arrangement of the detector 4 of the radiation scanning device shown in FIG. 1 will be described in detail below. The detector 4 may include multiple detector groups, which are located in a plane perpendicular to the transport direction of the object 6, with the ends of each detector group connected to each other and arranged to surround the scanning area. The multiple detector groups may be located in the same plane or in different planes perpendicular to the transport direction of the object 6. Optionally, they are installed in the same plane. In this embodiment, the detectors are located in the same plane as an example, but different planes are also applicable. Specifically, each detector group of the detector 4 is a detector array including multiple detector units, and the multiple detector groups may be arranged in a closed square, rectangular, polygonal, or elliptical structure surrounding the scanning area, with a portion of the structure located below the transmission device 1 so as to completely surround the transmission device 1.

[0152] FIG. 2 illustrates a detector arrangement according to some embodiments. The detector 4 includes four detector groups 41, 42, 43, and 44. Each detector group 41, 42, 43, and 44 is a linear detector array including multiple detector units arranged along a straight line. The four detector groups 41, 42, 43, and 44 are arranged on the four sides of the scanning area, with their ends connected to each other to form a closed rectangular structure (as shown in FIG. 6(a)) or a square structure. The arrangement of the detector 4 is not limited to the examples shown in FIGS. 2 and 6(a) and may instead have other configurations. For example, the detector 4 may include four long linear detector arrays and four short linear detector arrays, which are alternately arranged around the scanning area and whose ends are connected to each other to form a closed polygonal structure (as shown in FIG. 6(b)). Detector 4 can include other numbers of multiple long linear detector arrays and other numbers of multiple short linear detector arrays, alternating around the scan area and connected at their ends to form other closed polygonal structures. Detector 4 may also include other numbers, lengths, and / or shapes of detector groups to form other shapes of closed structures, such as elliptical structures.

[0153] A detector group in the form of a linear detector array may have any appropriate structure, and according to some embodiments, its specific structure is as shown in FIG. 7. As shown in FIG. 7, the detector group includes a plurality of detector units 45 and a detector arm 46, and the plurality of detector units 45 are arranged side by side along a line on the detector arm 46. The specific structure of the detector unit 45 may also have another appropriate structure, as shown in FIG. 8. As shown in FIG. 8, the detector unit 45 includes a detector crystal 451 for receiving radiation. The plurality of detector units 45 are arranged side by side on the detector arm 46 so that the detector crystals 451 face the same direction. The structure of the detector arm 46 is not limited to the embodiment shown in FIG. 7, and other appropriate structures (detector arm structures shown in FIGS. 9 and 15-17 below) may also be employed. The detector group of the present application is not limited to the form of a linear detector array, but may also have the form of an arc-shaped detector array to form a detector with an elliptical structure. The arc-shaped detector array may include a plurality of arc-shaped detector units and an arc-shaped detector arm, where the plurality of arc-shaped detector units are arranged side by side on the arc-shaped detector arm, and where the detector crystals of the detector units face in the same direction.

[0154] According to some embodiments, each detector group of the detector 4 can be individually detachable, thereby improving the maintainability of the detector. Optionally, the detector groups of the detector 4 are configured to be detached, attached, and adjusted along the transport direction of the object 6. In this way, when the detector 4 is arranged inside the radiation source 3 along a direction perpendicular to the transport direction of the object 6, the detector groups can be detached, adjusted, and maintained without the need to remove the radiation source, thereby further improving the maintainability of the detector.

[0155] Specifically, the detector group mounting and fixing structure of the present application allows the detector group of detector 4 to be moved along the transport direction of the subject 6 relative to the mounting position (e.g., support frame 5) in the radiation scanning device, and removed from or mounted to the mounting position.

[0156]

[0013] Hereinafter, a mounting structure for a detector group according to some embodiments of the present application will be described in detail. The mounting structure for a detector group according to some embodiments of the present application specifically includes a first mounting portion fixed to the detector group, a second mounting portion fixed to a support frame of a radiation scanning device and linearly movable to engage with the first mounting portion, the detector group being movable along the second mounting portion to a predetermined mounting position while the first mounting portion and the second mounting portion are engaged with each other, and a fixing device installed on one side along the width direction of the detector group and fixing the detector group to a mounting reference surface of the support frame. In some specific embodiments, the detector group is mounted and fixed to the support frame of the radiation scanning device via a detector arm, the first mounting portion being fixed to the detector arm of the detector group, and the fixing device being installed on one side along the width direction of the detector arm and fixing the detector arm to the support frame to fix the detector group.

[0157] 9 shows a detector group mounting and fixing structure according to some specific embodiments, where (a) in FIG. 9 shows an exploded perspective view of a detector arm and the mounting and fixing structure, and (b) in FIG. 9 is a partial cross-sectional view of the detector arm in the mounted and fixed state of the detector group. In FIG. 9, the complete detector group is not shown, but only the detector arm is shown, and multiple detector units may be arranged side by side along the longitudinal direction on the illustrated detector arm to form the complete detector group.

[0158] As shown in FIG. 9 , the first mounting portion of the detector group mounting and fixing structure is specifically formed as a slide groove 471 extending in the width direction of the detector arm 47. Here, when the detector arm 47 is mounted on the support frame 5 of the radiation scanning device, the width direction of the detector arm 47 coincides with the transport direction of the subject 6. The second mounting portion is formed as a slide rod 472 that engages with the slide groove 471. The slide groove 471 is formed as a semicircular opening slide groove, and the slide rod 472 is formed as a corresponding cylindrical slide rod. The slide rod 472 is fixed to the support frame 5 or formed integrally with the support frame 5, and its longitudinal direction coincides with the transport direction of the subject 6. One end of the slide rod 472 close to the support frame 5 is larger in size than the rest of the slide rod 472, and a protrusion 473 is formed. The end face of the protrusion 473 facing the detector arm 47 serves as a mounting reference surface 474 that abuts against a surface 475 on one side along the width direction of the detector arm 47. The surface 475 is a mounting surface for the detector arm 475, and is processed to have good flatness together with the mounting reference surface 474, and when the mounting surface 475 of the detector group is positioned by abutting against the mounting reference surface 474, the detector group can be accurately positioned in the width direction, i.e., in the transport direction of the subject 6. The protrusion 473 also functions as a position restricting part that, when mounting the detector group, aligns the slide groove 471 with the slide rod 472 and pushes the detector arm 47 along the slide rod 472 toward the support frame 5 until the detector arm 47 abuts against the protrusion 473, thereby moving the detector arm 47 to a predetermined mounting position.

[0159] The fixing device is provided at the other end of the slide rod 472 facing the protrusion 473, and is arranged so as to abut on both sides of the detector arm 471 along the width direction together with the protrusion 473, thereby determining the position of the detector arm 47 in the width direction. Specifically, the fixing device includes a positioning sleeve 476 and a fastener 477, the positioning sleeve 476 is fitted onto the other end of the slide rod 472 facing the protrusion 473, and abuts on a surface 478 on the other side along the width direction of the detector arm 47, and the fastener 477 fixes the positioning sleeve 476 to the other end of the slide rod 472 facing the protrusion 473. Specifically, the fastener 477 may be a fastening screw, and threaded holes are provided on both the positioning sleeve 476 and the other end of the slide rod 472. By screwing the fastening screw into the threaded hole, the positioning sleeve 476 is tightened relative to the slide rod 472, and the detector arm 47 is fixed in the width direction relative to the slide rod 472 (i.e., the support frame 5). At the same time, the engagement of the shapes of the slide rod 472 and the slide groove 471 restricts other degrees of freedom, so that the detector arm 47 can be perfectly positioned and fixed.

[0160] When attaching the detector group using the above-described attachment and fixation structure, first, with the detector unit facing the scanning area and the width direction aligned with the transport direction of the subject 6, the slide groove 471 of the detector arm 47 is aligned with the slide rod 472, and the detector arm 47 is moved along the slide rod 472 until it abuts against the convex portion 473, and then the positioning sleeve 476 is fitted onto one end of the slide rod 472 facing the convex portion 473 and fixed to the slide rod 472 with a screw, thereby fixing the detector arm 47. To remove the detector group, the reverse operation is performed.

[0161] With this mounting and fixing structure, the slide rod 472 extends along the transport direction of the subject 6, i.e., the linear movement engagement between the detector group and the support frame 5 is along the transport direction of the subject, and the fixing device is provided on one side along the width direction of the detector group, which coincides with the transport direction of the subject 6. Therefore, with the above mounting and fixing structure, the detector group can be attached and detached by moving it along the transport direction of the subject 6, and the tightening operation can also be performed on the side of the detector group along the transport direction of the subject, so that the detectors can be attached, detached, or maintained from the side along the transport direction of the subject, and even if the detector is arranged inside the radiation source along a direction perpendicular to the transport direction, attachment, detachment, or maintenance can be performed without interfering with the radiation source, and without the need to remove the radiation source, improving the convenience of attachment, detachment, and maintenance of the detectors.

[0162] Optionally, the second mounting portion of the mounting and fixing structure is arranged to support the detector group at a predetermined mounting position while engaged with the first mounting portion. Specifically, the second mounting portion includes two slide rods 472, and the detector arm 47 has two corresponding slide grooves 471 formed at both ends along the longitudinal direction of the detector arm 47. After the detector arm 47 is moved to the predetermined mounting position by the two slide rods 472, the two slide rods 472 can support the detector group at the predetermined mounting position without requiring any other auxiliary structure and / or tools. In this way, the detector group can be tightened without requiring any extra tools and the operator does not need to hold the detector group, improving operational convenience.

[0163] In Figure 9, the detector arm is shown as being vertically oriented, but the mounting and fixing structure is not limited to being used only for attaching and detaching a group of detectors arranged vertically in a radiation scanning device, and the mounting and fixing structure can also be used for a group of detectors arranged in other directions.

[0164] Of course, the mounting and fixing structure between the detector group and the support frame 5 is not limited to the embodiment shown in FIG. 9, and other suitable mounting and fixing structures may be adopted. For example, according to some embodiments, the linear movement engagement of the mounting and fixing structure may be other suitable engagement, for example, a linear rolling engagement such as engagement between a linear ball bearing and a cylindrical shaft. According to some other embodiments, the cross section of the slide groove 471 is not limited to a semicircular shape, but may be a shape such as a semirectangular shape, and accordingly, the slide rod 472 is not limited to a cylindrical body, but may be a shape such as a square pillar that engages with the slide groove 471.

[0165] Furthermore, when the detector includes multiple detector groups, by arranging the respective mounting reference surfaces of the multiple detector groups in the same plane perpendicular to the transport direction of the specimen 6, it is possible to ensure that the multiple detector groups, after being mounted, are located in the same plane perpendicular to the transport direction of the specimen 6. Specifically, when each detector group is mounted using a mounting and fixing structure such as that shown in Fig. 9, the end faces of the protrusions 473 corresponding to each detector group facing the detector arms 47, i.e., the mounting reference surfaces 474, are located in the same plane perpendicular to the transport direction of the specimen 6, and the mounting surfaces 475 along the width direction of each detector group are all abutted against and fixed to the respective mounting reference surfaces 474, so that the multiple detector groups, after being mounted, must be located in the same plane perpendicular to the transport direction of the specimen 6.

[0166] The relative arrangement of the radiation source 3 and the detector 4 of the radiation scanning device according to the embodiment of the present application will be further described below. As described above, the radiation source 3 includes a plurality of radiation source modules, each of which is arranged around the scanning region and located in the same plane perpendicular to the transport direction of the object 6. The detector 4 includes a plurality of detector groups, each of which is located in the same plane perpendicular to the transport direction of the object 6, and ends of each detector group are connected to each other so as to be arranged around the scanning region. Furthermore, in a combined state of the radiation source 3 and the detector 4, the detector 4 is arranged inside the radiation source 3 in a direction perpendicular to the transport direction of the object 6, and the radiation source 3 and the detector 4 are arranged to at least partially overlap each other in the transport direction of the object 6. The plurality of radiation source modules of the radiation source 3 may be arranged in any of the structures of the above-mentioned embodiments, such as a rectangular structure, a polygonal structure, or an elliptical structure. The plurality of detector groups of the detector 4 may be arranged in any of the structures of the above-mentioned embodiments, such as a square structure, a rectangular structure, a polygonal structure, or an elliptical structure. Hereinafter, the detailed arrangement of the combined state of the radiation source 3 and the detector 4 will be described using the embodiment shown in FIG. 2 as an example. In FIG. 2, the four linearly distributed radiation source modules 31, 32, 33, 34 of the radiation source 3 are arranged in a discontinuous rectangular structure, and the four linear detector arrays 41, 42, 43, 44 of the detector 4 are arranged in a closed rectangular structure. The detailed arrangement of the combined state described using FIG. 2 as an example can also be applied to any other structural combination of the radiation source 3 and the detector 4.

[0167] Optionally, each detector group 41, 42, 43, 44 of the detector 4 is arranged so as not to block the radiation beam of the radiation source module on the same side, and can receive radiation from each radiation source module on the other side. Since the radiation source 3 and the detector 4 are both arranged in a ring shape, the same detector group is shared by different radiation source modules of the radiation source. Figure 10 shows the correspondence between each radiation source module and the detector group that receives the radiation, where the radiation beam of each target point of each radiation source module 31, 32, 33, 34 of the radiation source 3 is shown as a fan beam (a radiation beam having an opening angle A as shown in Figure 3) as an example, and the radiation beam emitted from each radiation source module 31, 32, 33, 34 is detected by the detector groups on three sides of the detector 4, and the detector groups that can receive radiation and their parts are indicated by thick solid lines. 10(a) shows a detector group and its part corresponding to the radiation beam of the radiation source module 31 above the scanning area, and the detector group 42, 43, and 44 of detector 4 receive the radiation beam from the radiation source module 31. FIG. 10(b) shows a detector group and its part corresponding to the radiation beam of the radiation source module 32 on the right side of the scanning area, and the detector group 41, 43, and 44 of detector 4 receive the radiation beam from the radiation source module 32. FIG. 10(c) shows a detector group and its part corresponding to the radiation beam of the radiation source module 33 below the scanning area, and the detector group 41, 42, and 44 of detector 4 receive the radiation beam from the radiation source module 33. FIG. 10(d) shows a detector group and its part corresponding to the radiation beam of the radiation source module 34 on the left side of the scanning area, and the detector group 41, 42, and 43 of detector 4 receive the radiation beam from the radiation source module 34. As can be seen from Figure 10, radiation from one radiation source module is received by a detector group on the other side other than the detector group on the same side, and different radiation source modules can share the same detector group, for example, radiation source module 31 and radiation source module 32 share detector groups 43 and 44, radiation source modules 32 and 33 share detector groups 41 and 44, and radiation source modules 33 and 34 share detector groups 41 and 42.Furthermore, radiation from each radiation source module is not only detected by the detector group on the opposite side but also received by the detector groups on the other side other than the detector on the same side, so that radiation from each radiation source module is detected by as many detectors as possible. Therefore, the detector of the present application can improve image quality and reduce the number of detector groups, thereby reducing device costs.

[0168] Optionally, the detector crystal of each detector group of the detector 4 is disposed at an end of the detector unit along the transport direction of the object 6, adjacent to the edge of the radiation beam of the radiation source module on the same side in the transport direction of the object 6, but not blocking the radiation beam of the radiation source module on the same side. This minimizes the covering length of the optical path between the radiation source and the detector, thereby reducing the length of the device. More specifically, this is shown in FIGS. 11 and 12. FIG. 11 is a schematic cross-sectional structural view of the radiation scanning device shown in FIG. 1 according to some embodiments, taken along the center line along the transport direction of the object. 11, the detector unit may be, for example, the detector unit 45 shown in FIG. 7, and the detector crystal may be, for example, the detector crystal 451 shown in FIG. 7, where the surface of the detector crystal 451 is arranged parallel to the transport direction of the object 6 and is located at the end of the detector unit 45 along the transport direction of the object 6. At the same time, other members of the detector group, such as other elements and detector arms of the detector unit 45, are flush with the detector crystal 451 at the end of the detector unit 45, and all avoid the radiation beam exit port of the radiation source on the same side. Also, FIG. 12 shows a schematic plan view of the layout of detectors and radiation sources according to some embodiments, where the radiation source modules on the left and right sides in the figure are radiation source modules 34 and 32 of the radiation source 3, respectively, and detector crystals 451-4 and 451-2 on the left and right sides represent the positions of the detector crystals of the detector group 44 and 42, respectively. 12, the detector crystal 451-4 is provided adjacent to the edge of the radiation beam of the radiation source module 34 on the same side in the transport direction of the object 6 and does not block the radiation beam of the radiation source module 34 on the same side, and the detector crystal 451-2 is provided adjacent to the edge of the radiation beam of the radiation source module 32 on the same side in the transport direction of the object 6 and does not block the radiation beam of the radiation source module 32 on the same side. With the above configuration, the radiation source 3 and the detector 4 can be overlapped to the maximum extent in the transport direction of the object 6, so that the covering length of the optical path between the radiation source and the detector can be shortened as much as possible, and the length of the apparatus can be shortened.

[0169] Optionally, each radiation source module of the radiation source 3 is arranged so that the radiation beam avoids the detector group on the same side and irradiates the detector crystal of the detector group on the opposite side. As shown in FIG. 12 , the radiation beam of the radiation source module 34 can avoid the detector group 44 on the same side and irradiate the detector crystal 451-2 of the detector group 42 on the opposite side, and the radiation beam of the radiation source module 32 can avoid the detector group 42 on the same side and irradiate the detector crystal 451-4 of the detector group 44 on the opposite side. Furthermore, each radiation source module of the radiation source 3 is arranged so that the detector crystal of the detector group on the opposite side is irradiated at the center position of the radiation beam. Specifically, the radiation source module can be rotated by a predetermined angle with respect to the target axis to adjust the beam emission angle of the radiation beam of the radiation source module, so that the radiation beam can irradiate the detector crystal at its center position. Here, the target axis is a line that virtually connects multiple target points in the radiation source module. Since the detector crystal of the detector is located at the end position of the detector unit in the transport direction of the object 6 and is disposed adjacent to the edge of the radiation beam of the radiation source on the same side, the radiation beam can be irradiated at its center position by rotating the radiation source module by a very small predetermined angle, for example, 1.5 degrees. In this way, it is possible to minimize the adverse effects on imaging caused by the radiation beam being incident obliquely on the surface of the detector crystal. Furthermore, the rotation of the radiation source module is not limited to rotation around the target axis, and the radiation source module may be rotated about an axis other than the target axis to adjust the beam exit angle of the radiation beam. Here, the rotation of the radiation source about the target axis or another axis can be realized by the above-mentioned mounting and positioning structure of the radiation source module. Furthermore, the manner in which the beam exit angle of the radiation beam is adjusted is not limited to the above embodiment. As long as the above-mentioned arrangement of the radiation source can be realized, the radiation beam exit angle may be changed by other methods, such as changing the aperture direction of the radiation source module, adjusting the collimator, or other appropriate methods.

[0170] In the radiation scanning device of the present application, the radiation source comprises a plurality of radiation source modules, the ends of which may be directly connected or spaced apart. When the ends of the radiation source modules are directly connected, the radiation source points between adjacent radiation source modules are not necessarily contiguous due to the mechanical connection between the ends. For example, the distance between the target points at the ends of two adjacent radiation source modules is significantly greater than the distance between the target points within the radiation source module, even when the ends of the radiation source modules are spaced apart. Therefore, during the scanning process, the target points at the ends of adjacent radiation source modules are missing, resulting in missing projection data. In response to this, according to some embodiments, the image processing module of the radiation scanning device of the present application is configured to have a data compensation function that can compensate for missing data in the field of view and / or repair the reconstructed image, thereby improving image quality. Specifically, the image processing module is configured to perform image reconstruction using an iterative method, an image region repair method, or a combination of both.

[0171] The iterative method specifically includes the following steps:

[0172] In step 1, image reconstruction is performed using missing field of view data, which is initial data measured by a detector, and the initial data lacks projection data for field of view angles where there is no target point. For example, if a radiation scanning device uses a radiation source with a discontinuous rectangular structure as shown in Figure 2 or Figure 4(a), the initial data measured by the detector lacks projection data for oblique field of view angles at the four corners of the rectangular structure.

[0173] In step 2, the reconstructed image acquired in step 1 is reprojected forward according to complete geometry. Here, the reconstructed image acquired in step 1 may present an object with an incomplete geometric structure because it uses missing data from the viewing angle. Performing forward projection according to complete geometry refers to performing forward reprojection when the geometric shape is completely completed. Specifically, the geometric shape can be completely completed by methods such as inference and hypothesis.

[0174] In step 3, the reprojected data obtained in step 2 is referenced, and the missing data in the field of view is restored in the projection region using an image restoration algorithm, and image reconstruction is performed again using the restored data.

[0175] In step 4, the forward reprojection step, the view angle missing data repair step, and the image reconstruction step are repeated multiple times, and the image obtained in the final image reconstruction step is taken as the final reconstructed image.

[0176] In the above iterative method, a convergence threshold can be preset, and if the image acquired in the image reconstruction step satisfies the set convergence threshold, the iteration is stopped and the image is taken as the final reconstructed image, and if the image acquired in the image reconstruction step does not satisfy the set convergence threshold, the next iteration, i.e., the forward reprojection step, the view angle missing data repair step, and the image reconstruction step, is continued until the image acquired in the image reconstruction step satisfies the set convergence threshold.

[0177] In the above iterative method, the image restoration algorithm in step 2 includes various conventional algorithms, such as methods based on TV regularization, wavelet analysis, dictionary learning, etc., and artificial neural network methods.

[0178] In the above iterative method, the image reconstruction method includes conventional algorithms such as an analytical algorithm and an iterative algorithm.

[0179] According to another embodiment, the image processing module can also obtain a reconstructed image using an image domain inpainting method. Specifically, the image processing module can perform image reconstruction using missing field of view data, i.e., initial data measured by a detector, and then perform artifact removal and data correction processing on the reconstructed image using an image domain inpainting algorithm in the image domain to obtain a final reconstructed image. In this embodiment, the image inpainting algorithm can include various conventional algorithms, such as methods based on TV regularization, wavelet analysis, dictionary learning, and artificial neural network methods.

[0180] According to some other embodiments, the image processing module can perform image reconstruction using a combination of the iterative method and the image region inpainting method to improve image quality. Specifically, the image processing module can first use the iterative method to fill in missing data in the projection domain to obtain a reconstructed image that satisfies a set convergence threshold, and then use the image region inpainting method to perform artifact removal and data correction processing on the reconstructed image obtained by the iterative method in the image domain using an image inpainting algorithm to obtain a final reconstructed image.

[0181] Compared with a radiation source adopting a distributed multi-point source, the source points of a radiation source adopting a single-point source format are relatively sparse, and the image processing module can adopt an image reconstruction algorithm applied to sparse field of view data to obtain a scanned image.

[0182] In the radiation scanning device of the above embodiment, the radiation source surrounds the scanning area on four sides, i.e., top, bottom, left, and right. According to another embodiment, the present application further provides a radiation scanning device, the layout of which is basically the same as that of the radiation scanning device of the above embodiment, with the main difference being the layout of the radiation source, in which the radiation source surrounds the scanning area on only one of the top, bottom, left, and right sides. In the following description, the case where the radiation source is arranged on the top, bottom, and right sides of the scanning area will be described as an example, but the same applies when the radiation source is arranged on the top, bottom, and left sides of the scanning area.

[0183] Specifically, in the radiation scanning device of the above embodiment, each radiation source module of the radiation source 3 is a distributed multi-point source, and the multiple radiation source modules may be arranged in a rectangular structure, a polygonal structure, an elliptical structure, etc. surrounding the scanning area. In this embodiment, the multiple radiation source modules of the radiation source may still be distributed multi-point sources, with the difference being that the multiple radiation source modules are arranged in an open structure surrounding the scanning area and opening on the left side of the scanning area, such as a rectangular structure, a polygonal structure, an elliptical structure, etc. opening on the left side, where the left side of the scanning area refers to the left side in a direction perpendicular to the transport direction of the object 6 in the scanning area. In the above embodiments, the radiation sources 3 are arranged in a discontinuous or continuous rectangular structure, a continuous polygonal structure, a continuous rounded rectangle, a discontinuous polygonal or discontinuous rounded rectangle structure, and other polygonal and elliptical structures. Accordingly, in this embodiment, the radiation sources are arranged in a discontinuous or continuous rectangular structure, a continuous polygonal structure, a continuous rounded rectangle, a discontinuous polygonal or rounded rectangle structure, and other polygonal and elliptical structures that open to the left of the scanning region. For example, compared to the radiation source shown in FIG. 2 , the radiation source 3 of this embodiment does not include at least the radiation source module 34 on the left side of the scanning region. For example, compared to the radiation sources shown in FIGS. 4(b) to 4(c), the radiation source 3 of this embodiment does not include at least the radiation source module on the left side of the object 6.

[0184] Similarly to the previous embodiment, the radiation source of this embodiment may be composed of a group of multiple single point sources. The only difference from the previous embodiment is that the radiation source 3 of this embodiment does not include a single point source at the left field of view, or does not include single point sources at the left field of view, the upper-left oblique field of view, and the lower-left oblique field of view.

[0185] Except for the above differences, the other features of the radiation source of this embodiment are all the same as those of the radiation source 3 of the previous embodiment.

[0186] The detector of this embodiment has basically the same features as the detector 4 of the previous embodiment, except that in this embodiment, the detector is combined with radiation sources that surround the scanning area only from the upper, lower, and right sides, and there is no radiation source module on the same side of the detector group located on the left side of the scanning area of ​​the detector 4. Therefore, the detector groups of the detector 4 can be attached and detached in the same manner as in the previous embodiment, or in a different manner from the previous embodiment, as described below, which further facilitates the attachment, detachment, and maintenance of the detectors. Specifically, taking the combination of the detector group and radiation source shown in FIG. 13 as an example (here, the detector group is the same as the detector group shown in FIG. 2, and the radiation source is missing a radiation source module on the left side of the scanning area compared to the radiation source shown in FIG. 2), the detector 4 is such that detector groups 41′, 43′, and 44′ are attached to and detached from the support frame 5 in a direction perpendicular to the transport direction of the subject 6 (X direction as shown in FIG. 14), and detector group 42′ is attached to and detached from the support frame 5 along the transport direction of the subject 6 (Z direction as shown in FIG. 14).

[0187] Detector group 42' can be attached or detached to support frame 5 using the same mounting and fastening structure as in the above-described embodiment (as shown in FIG. 9). However, the mounting and fastening structure in the above-described embodiment is not suitable for attaching or detaching detector groups 41', 43', and 44' along the X direction, so a different mounting and fastening structure is required. Specific examples of these mounting and fastening structures are described in detail below.

[0188] Similar to the mounting and fixing structure of the above embodiment, the mounting and fixing structure suitable for attaching and detaching the detector groups 41', 43', 44' in the X direction also specifically comprises a first mounting part, a second mounting part, and a fixing device, the first mounting part is fixedly installed on the detector group, the second mounting part is fixedly installed on the support frame of the radiation scanning equipment and engages with the linear movement of the first mounting part, wherein the detector group can move to a predetermined mounting position along the second mounting part with the first mounting part and the second mounting part engaged with each other, and the fixing device is provided on one side along the width direction of the detector group and is used to fix the detector group to the mounting reference surface on the support frame. In some specific embodiments, the detector groups 41', 43', 44' are attached and fixed to the support frame of the radiation scanning equipment via detector arms, wherein the first attachment portion is fixedly attached to the detector arm, and the fixing device is provided on one side along the width direction of the detector arm, and fixes the detector group by fixing the detector arm to the support frame.

[0189] 15 shows a mounting and fixing structure suitable for a detector group 41' according to some specific embodiments, in which (a) of FIG. 15 shows a perspective view of the detector group in an mounted state, (b) of FIG. 15 shows a side view of the detector group in an mounted state, (c) of FIG. 15 shows a perspective view of the detector group in a detached state, and (d) of FIG. 15 shows a cross-sectional view of the detector group with the fixing device in an mounted state. As shown in FIG. 15, a first mounting portion of the mounting and fixing structure for the detector group 41' includes a slider 412 provided on a detector arm 411, and the slider 412 extends along the longitudinal direction of the detector arm 411, and when the detector group 41' is mounted on the radiation scanning device, the longitudinal direction of the detector arm 411 is perpendicular to the transport direction of the subject 6. 15, the slider 412 extends a portion of the length of the detector arm 411, in other embodiments the slider 412 may be provided to extend the entire length of the detector arm 411 or some other length. The slider 412 may also be secured to the detector arm 411 by a bolted connection or the like. According to other embodiments, the slider 412 may be integrally formed with the detector arm 411.

[0190] The second mounting portion is formed as a fixed guide rail 413 that engages with the slider 412. The fixed guide rail 413 is fixedly connected to a support frame 5 (not shown in FIG. 15) of the radiation scanning device, and may be molded integrally with the support frame 5. The longitudinal direction of the fixed guide rail 413 is perpendicular to the direction in which the subject 6 is transported in the radiation scanning device. A position restricting portion (not shown) may be provided at one end along the longitudinal direction of the fixed guide rail 413, and when mounting the detector group 41′, the slider 412 is aligned with the fixed guide rail 413, and the detector group 41′ is pushed along the fixed guide rail 413 until the detector arm 411 abuts against the position restricting portion, thereby moving the detector group 41′ to a predetermined mounting position.

[0191] The fixing device is provided on one side of the detector group 41′ in the width direction and abuts against a surface 414 on one side of the detector arm 411 in the width direction. Specifically, the fixing device includes a positioning member 415 and a fastener 416. The positioning member 415 is fixedly connected to the support frame 5, and an end face away from the support frame 5 is formed as a mounting reference surface 417. The mounting reference surface 417 is used to abut against the surface 414 on one side of the detector arm 411 in the width direction. The surface 414 is the mounting surface of the detector arm 411 and is machined to have good flatness together with the mounting reference surface 417. When the mounting surface 414 of the detector arm 411 is fixed in abutment against the mounting reference surface 417, the detector group 41′ can be accurately positioned in the width direction. The fastener 416 passes through the positioning member 415 and can fasten the detector group 41′ to the end face of the positioning member 415. Specifically, the fasteners 416 may be, for example, fastening bolts, and corresponding screw holes are provided on the positioning member 415 and on the side surfaces of the detector arm 411 facing the positioning member 415, and the fastening bolts 416 can be passed through the corresponding screw holes and tightened to fasten the detector group 41′ to the end surface of the positioning member 415. A plurality of fixing devices, for example at least two, may be provided along the longitudinal direction of the detector group 41′ so as to firmly fix the detector group 41′ to the support frame 5.

[0192] When attaching the detector group 41' using the above-described attachment and fixation structure, first, with the detector units of the detector group 41' facing downward, the sliders 412 of the detector group 41' are aligned with the fixed guide rails 413, the detector group 41' is moved along the fixed guide rails 413 until it abuts against the position restricting portions of the fixed guide rails 413, and then the fastening bolts 416 are passed through corresponding screw holes in the positioning member 415 and the detector arm 411 and tightened, thereby positioning the detector group 41' with respect to the end face of the positioning member 415, i.e., the attachment reference surface 417. When removing the detector group 41', the reverse operation can be performed.

[0193] Because the length direction of the fixed guide rail is perpendicular to the direction in which the object 6 of the radiation scanning device is transported and there is no interference from the radiation source on one side of the detector group 41' along the X direction, the above mounting and fixing structure allows the detector group 41' to be attached to and detached from the support frame 5 in a direction perpendicular to the direction in which the object 6 of the radiation scanning device is transported. In addition, because the fixing device is installed on one side of the detector group along the width direction, i.e., on one side of the detector along the Z direction, the detector group can be fastened without shielding the radiation source, which makes it convenient to attach, detach, and maintain the detector group.

[0194] Optionally, in the above mounting and fixing structure, the second mounting portion may be arranged to support the detector group 41' at a predetermined mounting position while engaged with the first mounting portion. Specifically, the slider 412 is provided on both opposing sides along the width direction of the detector arm 411, and has inner extending portions 4121, 4122 extending inward from edges of the detector arm 411 on both opposing sides along the width direction (see FIG. 15(b)), the fixed guide rail 413 includes outer extending portions 4131, 4132 extending outward on both opposing sides along the width direction (see FIG. 15(b)), and when the slider 412 is engaged with the fixed guide rail 413, the inner extending portions 4121, 4122 of the slider 412 are located above the outer extending portions 4131, 4132 of the fixed guide rail 413, and the two are arranged in contact with each other and overlap each other. As a result, after the detector group 41' has moved along the fixed guide rail 413 to a predetermined mounting position, the detector group 41' is suspended from the outer extending portions 4131, 4132 of the fixed guide rail 413 by the inner extending portions 4121, 4122 of the slider 412. In this way, the fixed guide rail 413 can support the detector group 41' at a predetermined mounting position, without requiring any additional auxiliary structure or tool, and the operator does not need to hold the detector group 41' when tightening the detector group 41', thereby improving convenience of operation.

[0195] Similar to the detector group 41', the detector group 43' is attached and detached using a combination of a slider and a fixed guide rail. Specifically, Fig. 16 shows an attachment and fixing structure suitable for the detector group 43' according to some specific embodiments, with Fig. 16(a) showing a perspective view of the detector group in an attached state and Fig. 16(b) showing a side view of the detector group in an attached state.

[0196] 16, a first mounting portion of the mounting and fixing structure for the detector group 43' includes a slider 432 provided on a detector arm 431, the slider 432 extending along the longitudinal direction of the detector arm 431, and when the detector group 43' is attached to the radiation scanning device, the longitudinal direction of the detector arm 431 is perpendicular to the transport direction of the subject 6 in the radiation scanning device. The slider 432 may be fixed to the detector arm 431 by bolt connection or the like, or may be molded integrally with the detector arm 431. A groove 433 extending in the longitudinal direction is formed in the detector arm 431, and the slider 432 is provided in this groove 433.

[0197] The second mounting portion is formed as a fixed guide rail 434 that engages with the slider 432. The fixed guide rail 434 is fixedly connected to a support frame 5 of the radiation scanning device and may be molded integrally with the support frame 5. The longitudinal direction of the fixed guide rail 434 is perpendicular to the transport direction of the subject 6. A position restricting portion (not shown) may be provided at one end along the longitudinal direction of the fixed guide rail 434, and when mounting the detector group 43', the slider 432 is aligned with the fixed guide rail 434, and the detector group 43' is pushed along the fixed guide rail 434 until the detector arm 431 abuts against the position restricting portion, thereby moving the detector group 43' to a predetermined mounting position.

[0198] The fixing device for the detector group 43' is the same as that for the detector group 41', and the specific structure of the fixing device will not be described in detail here. This fixing device allows the detector group 43' to be fastened and fixed to a corresponding mounting reference surface on the support frame 5. A mounting surface is also provided on one side of the detector arm 431 of the detector group 43' along the width direction. Similarly, this mounting surface and the mounting reference surface of the support frame 5 are processed to have good flatness, so that the detector group 43' can be accurately positioned in the width direction when the mounting surface of the detector arm 431 abuts on the mounting reference surface. Similarly, multiple fixing devices, for example at least two, may be provided along the longitudinal direction of the detector group 43' to firmly fix the detector group 43' to the support frame 5.

[0199] When attaching the detector group 43' using the above-described attachment and fixation structure, if the detector units are facing upward, first align the sliders 432 of the detector group 43' with the fixed guide rails 434, move the detector group 43' along the fixed guide rails 434 until it abuts against the position regulating portions of the fixed guide rails 434, and then pass the fastening bolts through the corresponding screw holes in the positioning member and detector arms and tighten them, thereby positioning the detector group 43' with respect to the attachment reference surface of the positioning member. To remove the detector group 43', simply perform the reverse operation.

[0200] Because the length direction of the fixed guide rail is perpendicular to the direction in which the object 6 is transported in the radiation scanning device and there is no interference from the radiation source on one side of the detector group 43' along the X direction, the above-mentioned mounting and fixing structure allows the detector group 43' to be attached to and detached from the support frame 5 in a direction perpendicular to the direction in which the object 6 is transported in the radiation scanning device. In addition, because the fixing device is provided on one side of the detector group 43' along the width direction, i.e., on one side of the detectors along the Z direction, the detector group can be fastened without blocking the radiation source, which makes it convenient to attach, detach, and maintain the detector group.

[0201] Optionally, in the above mounting and fixing structure, the second mounting portion may be configured to support the detector group 43' at a predetermined mounting position while engaged with the first mounting portion. Specifically, as shown in Fig. 16, the fixed guide rail 434 includes receiving portions 4341 and 4342, which not only slidably engage with the slider 432 but also support the slider 432 below, thereby supporting the detector group 43' at the predetermined mounting position from below after the detector group 43' has moved along the fixed guide rail 434 to the predetermined mounting position. This allows the detector group 43' to be tightened without the need for a separate tool or for the operator to support the detector group 43', improving operability.

[0202] Figure 17 shows a mounting and fixing structure suitable for a detector group 44' in some specific embodiments, where (a) of Figure 17 shows a perspective view of the detector group in an mounted state, (b) of Figure 17 is a schematic diagram of the mounting and fixing structure in a state where the first mounting part and the second mounting part are separated, and (c) of Figure 17 and (d) of Figure 17 are perspective views of different viewing angles in a state where the first mounting part and the second mounting part of the mounting and fixing structure are engaged.

[0203] The first mounting portion of the mounting and fixing structure for the detector group 44' is specifically formed as a fixing block 442 provided on one side along the width direction of the detector arm 441, and the fixing block 442 has an opening 443 on one side along the thickness direction of the detector arm 441. When the detector group 44' is mounted, the width direction of the detector arm 441 coincides with the transport direction of the subject 6 of the radiation scanning device, and the thickness direction is perpendicular to the transport direction of the subject 6. The opening 443 of the fixing block 442 may be U-shaped or have any other appropriate shape. The fixing block 442 may be fixedly connected to the detector arm 441 by a method such as bolt fixing, or may be formed integrally with the detector arm 441.

[0204] The second mounting portion is formed as a cantilever portion 444 fixed to the support frame 5, and an extension portion 445 is provided at the end of the cantilever portion 444 away from the support frame 5. The extension portion 445 is engaged with the opening 443 in the fixed block 442 so as to be linearly movable, i.e., the extension portion 445 can be linearly moved from the edge of the opening 443 to the inside of the opening 443. The longitudinal direction of the cantilever portion 444 coincides with the direction of transportation of the subject 6 in the radiation scanning device. The bottom of the opening 443 functions as a position restriction portion that, when mounting the detector group 44′, defines the detector group 44′ at a predetermined mounting position by aligning the opening 443 of the fixed block 442 on the detector arm 441 with the extension portion 445 and moving the detector arm 441 linearly relative to the extension portion 445 until the bottom of the opening 443 abuts against the extension portion 445.

[0205] The fixing device is provided on one side of the detector arm 441 along the width direction (the same side as the fixing block 442), and an end face of the fixing device is formed as a mounting reference surface, and the detector arm 441 is fastened to the mounting reference surface. Specifically, the fixing device may include a fixing tool 446 and a fastener 447, and the end face of the fixing tool 446 away from the support frame 5 is formed as a mounting reference surface 448 for abutting against a surface 449 on one side along the width direction of the detector arm 441. The surface 449 is the mounting surface of the detector arm 441 and is machined to have good flatness together with the mounting reference surface 448. When the mounting surface 449 of the detector arm 441 is abutted against the mounting reference surface 448 and fixed, the detector group 44′ can be accurately positioned in the width direction. The fastener 447 is used to fasten the detector arm 441 to the end face 448 of the fixing tool 446. The fastener 447 may be a fixing bolt, and a corresponding screw hole is formed in the fixing device 446 and on the side of the detector arm 441 facing the fixing device 446 along the width direction, and the fixing bolt 447 passes through the corresponding screw holes in the fixing device 446 and the detector arm 441 and is tightened to fasten the detector group 44' to the mounting reference surface 448. Also, a plurality of fixing devices, for example at least two, may be included, and the plurality of fixing devices may be arranged at intervals along the longitudinal direction of the detector group 44' to firmly fix and position the detector group 44'.

[0206] When attaching the detector group 44' using the above-described attachment and fixation structure, first, with the detector units facing the scanning region and with their width direction coinciding with the transport direction of the subject 6, the openings 443 of the fixing blocks 442 in the detector group 44' are aligned with the extensions 445 of the cantilever portions 444, and the detector group 44' is moved along the extensions 445 until the bottoms of the openings 443 abut against the extensions 445, and then the fasteners 447 are passed through the corresponding screw holes in the fixture 446 and the detector arm 441 and tightened to position the detector group 44' relative to the attachment reference surface 448 of the fixture 446. To remove the detector group 44', the reverse operation is performed.

[0207] As a result, by utilizing the above-mentioned mounting and fixing structure, the cantilever portion 444 extends along the transport direction of the subject 6 in the radiation scanning device, the width direction of the detector group 44' is parallel to the transport direction of the subject 6, and the opening 443 of the fixing block 442 faces the thickness direction side of the detector group 44', so that by facing the detector crystal toward the scanning area, the detector group 44' can be attached or detached in a direction perpendicular to the transport direction of the subject 6.

[0208] Optionally, in the above mounting and fixing structure, the second mounting portion is arranged to support the detector group 44' at a predetermined mounting position while engaged with the first mounting portion. That is, after the detector group 44' is moved to a predetermined installation position relative to the extension portion 445 of the cantilever portion 444, the entire detector group 44' can be supported by the fixing block 442, without the need for other auxiliary structures or tools. In this way, no extra tools are needed when fastening the detector group 44', and the operator can perform the operation without holding the detector group 44', improving convenience of operation.

[0209] Each of the detector groups 41', 42', 43', and 44' is attached to and detached from the support frame 5 using a different fixed mounting structure, but after being attached, each detector group may be located together with the other detector groups in the same plane perpendicular to the transport direction of the test object 6. Specifically, by setting the mounting reference plane of each detector group in the same plane perpendicular to the transport direction of the test object 6, it is possible to ensure that each of the detector groups 41', 42', 43', and 44' is located in the same plane perpendicular to the transport direction of the test object 6 after being attached.

[0210] In addition, the linear movement engagement between the first mounting part and the second mounting part of the fixed mounting structure in Figures 15 and 16 employs an engagement between a slider and a guide rail, but according to other embodiments, the fixed mounting structure of the present application may employ other linear movement engagements, such as a linear slide or linear rolling engagement, or may employ an engagement between a linear ball bearing and a cylindrical shaft.

[0211] The above has described the mounting and fixing structure of the detector group of the detector 4 of the radiation scanning device of this embodiment. Below, the features of other aspects of the radiation scanning device of this embodiment will be described.

[0212] The relative arrangement of the radiation source 3 and the detector 4 of the radiation scanning device of this embodiment is basically the same as that of the previous embodiment. As in the previous embodiment, the radiation source 3 includes a plurality of radiation source modules, each of which is arranged so as to surround the scanning region and is located in a plane, particularly in the same plane, perpendicular to the transport direction of the object 6; the detector 4 includes a plurality of detector groups, each of which is located in another plane, particularly in the same plane, perpendicular to the transport direction of the object 6, and the ends of each detector group are connected to each other and arranged so as to surround the scanning region; and further, in a combined state of the radiation source 3 and the detector 4, the detector 4 is arranged so as to surround the scanning region in a direction perpendicular to the transport direction of the object 6. The detector 4 is disposed inside the radiation source 3, and the radiation source 3 and the detector 4 are disposed so as to at least partially overlap in the transport direction of the subject 6. The group of multiple detectors in the detector 4 may have any of the structures described in the above-mentioned embodiments, such as a closed square structure, rectangular structure, polygonal structure, or elliptical structure, surrounding the scanning area. What is different from the above-mentioned embodiment is that the multiple radiation source modules in the radiation source 3 are disposed in an open structure surrounding the scanning area, which is open on the left side of the scanning area, and may be, for example, a rectangular structure, polygonal structure, or elliptical structure, which is open on the left side.

[0213] As in the previous embodiment, each detector group of the detector 4 in this embodiment can be selectively positioned so as not to block the radiation beam of the radiation source module on the same side, while receiving radiation from each radiation source module on the other side. Because the radiation source 3 and the detector 4 are both arranged in a ring shape (the radiation source 3 is a half-open ring with an open left side), the same detector group can be shared by different radiation source modules of the radiation source. Furthermore, radiation from each radiation source module of the radiation source 3 can be detected not only by the detector group on the opposite side but also by the detector group on the other side, allowing as much radiation from each radiation source module as possible to be detected by the detector. Therefore, the detector of this embodiment similarly improves image quality and reduces the number of detector groups, thereby reducing device costs.

[0214] Also, similarly to the above embodiment, the detector crystals of each detector group of the detector 4 are optionally arranged at an end of the detector unit along the transport direction of the object 6, adjacent to the edge of the radiation beam of the radiation source module on the same side in the transport direction of the object 6, but not blocking the radiation beam of the radiation source module on the same side. This makes it possible to minimize the covering length of the optical path between the radiation source and the detector, thereby reducing the length of the apparatus.

[0215] As in the previous embodiment, each radiation source module of the radiation source 3 is optionally arranged so that its radiation beam avoids the detector group on the same side and irradiates the detector crystal of the detector group on the opposite side. Specifically, as in the previous embodiment, the radiation source module can be rotated by a predetermined angle with respect to the target axis to adjust the beam exit angle of the radiation beam from the radiation source module, thereby irradiating the detector crystal at the center position of the radiation beam. Because the detector crystal of the detector is located at the end position of the detector unit in the transport direction of the subject 6 and is arranged adjacent to the edge of the radiation beam of the radiation source on the same side, the radiation source module can be rotated by a very small predetermined angle, for example, 1.5 degrees, to irradiate the detector crystal at the center position of the radiation beam. In this way, adverse effects on imaging caused by the radiation beam being obliquely incident on the surface of the detector crystal can be minimized. As in the previous embodiment, the radiation source module can be rotated about the target axis or another axis, or the beam exit angle of the radiation beam can be adjusted by any other appropriate method described in the previous embodiment.

[0216] In addition, since the radiation source of this embodiment also lacks projection data at the end of the adjacent radiation source module, similar to the previous embodiment, the image processing module of the radiation scanning device of this embodiment is also configured with a data compensation function to compensate for the missing data in the field of view and / or restore the reconstructed image to improve image quality. The image processing module of the radiation scanning device of this embodiment performs image reconstruction in the same manner as the previous embodiment.

[0217] The radiation scanning device of this embodiment has the same effects as the radiation scanning devices of the above-described embodiments, and also has the following advantages.

[0218] The radiation scanning device of this embodiment is particularly applicable to airport baggage security checks. Airport baggage is characterized by its small volume (e.g., typically less than 600mm x 400mm), large length, width, and small thickness. When placed on a transmission device for detection, the thickness is typically along the vertical direction, the width along the horizontal direction, and the length along the transport direction. The radiation scanning device of this embodiment has radiation source modules located on both the top and bottom of the scanning area to scan the baggage in the thickness direction. This allows for more projection data to be obtained in the thickness direction, which is a small size. Furthermore, because the baggage is thin, the projection data in the thickness direction is less affected by self-shielding and radiation attenuation, so the projection data in the thickness direction is more accurate and clearer than in other directions, which is advantageous for improving image quality. At the same time, the radiation source of the radiation scanning device of the present application is provided with a radiation source module installed on only one side of the width direction of the luggage, and in the width direction, the projection data is significantly affected by self-shielding and radiation attenuation by the luggage, so the quality of the projection data is poorer than the quality of the projection data in the thickness direction. Therefore, by installing a radiation source module on only one side of the width direction of the luggage, it is possible to ensure image quality and reduce the cost of the radiation source.

[0219] Although the radiation scanning device of this embodiment does not have a radiation source installed on the left side of the scanning area, a right detector group is still installed opposite the left side of the scanning area, and the right detector group can receive radiation from the radiation source modules above and below, thereby increasing the corresponding detection data of the radiation from the radiation source modules above and below, thereby improving image quality compared to when detector groups are installed only on the opposite sides of each radiation source module.

[0220] Furthermore, although the present embodiment has been described by way of example in which the multiple radiation source modules of the radiation source are arranged in the same plane perpendicular to the transport direction of the subject, the present embodiment can also be applied to a case in which the multiple radiation source modules of the radiation source are arranged in different planes perpendicular to the transport direction of the subject.

[0221] In addition, in this embodiment, an example has been described in which multiple detector groups of detectors are arranged in the same plane in the transport direction of the subject, but the same applies to cases in which multiple detector groups of detectors are arranged in different planes perpendicular to the transport direction of the subject.

[0222] In the above embodiment, the radiation scanning device is described in which the radiation source surrounds the scanning area on all four sides (top, bottom, left, and right). In another embodiment, the present application further provides a radiation scanning device whose layout is essentially the same as that of the radiation scanning device in the above embodiment, with the main difference being the layout of the radiation source. In this embodiment, the radiation source surrounds the scanning area only on three sides (top, bottom, left, and right). That is, the radiation source surrounds the scanning area only above the transmission device, and no radiation source module is provided below the transmission device (see FIG. 18 , which shows a schematic layout of the radiation source and detector according to this embodiment). Here, “above the transmission device” refers not only to directly above the transmission device, but also to above the side of the transmission device. Furthermore, “above the transmission device” does not necessarily have to be strictly higher than the transmission device; cases where the height is approximately the same as that of the transmission device or slightly lower than that of the transmission device are also included within the scope of this embodiment.

[0223] Specifically, in the radiation scanning device of the above embodiment, each radiation source module of the radiation source 3 is a distributed multi-point source, and the multiple radiation source modules may be arranged in a rectangular structure, a polygonal structure, an elliptical structure, etc. surrounding the scanning area. In this embodiment, the multiple radiation source modules of the radiation source may be distributed multi-point sources, with the difference being that the multiple radiation source modules are arranged in an open structure opening below the transmission device surrounding the scanning area, such as a rectangular structure, a polygonal structure, an elliptical structure, etc. In the above-mentioned embodiments, the radiation sources 3 are arranged in a discontinuous or continuous rectangular structure, a continuous polygonal structure, a continuous rounded rectangle, a discontinuous polygonal or discontinuous rounded rectangle structure, and other polygonal and elliptical structures. However, in the present embodiment, the radiation sources are arranged in a discontinuous or continuous rectangular structure, a continuous polygonal structure, a continuous rounded rectangle, a discontinuous polygonal or discontinuous rounded rectangle structure, and other polygonal and elliptical structures that open below the transmission device. For example, compared to the radiation source shown in FIG. 2 , the radiation source 3 of this embodiment does not include at least the lower radiation source module 33, and in some cases does not include the parts of the radiation source modules 32 and 34 that are lower than the transmission device 1. For example, compared to the radiation sources shown in FIGS. 4(b) to 4(c), the radiation source 3 of this embodiment does not include at least the radiation source module below the subject 6.

[0224] Also, similar to the above embodiment, the radiation source of this embodiment may be composed of a group of multiple single point sources, the only difference being that the radiation source 3 of this embodiment does not include single point sources at the bottom viewing angle, the lower left oblique viewing angle and the lower right oblique viewing angle.

[0225] Except for the above differences, the other features of the radiation source of this embodiment are all the same as those of the radiation source 3 of the previous embodiment.

[0226] The detector of this embodiment has essentially the same features as the detector 4 of the previous embodiment, except that the detector is combined with radiation sources that surround the scanning area only from the upper, left, and right sides, and the detector groups located below the scanning area of ​​the detector 4 do not have radiation source modules on the same side, so that the installation and removal of the detector groups located below the scanning area of ​​the detector 4 is not hindered by the lower radiation source module. Therefore, each detector group of the detector can be installed and removed using the same mounting and fastening structure as in the previous embodiment, and can also be installed and removed from the support frame 5 in a direction perpendicular to the transport direction of the object 6, provided that the detector groups located below the scanning area are not hindered by the radiation source modules on the left or right sides. Specifically, they can be installed and removed using the mounting and fastening structure described with reference to FIG.

[0227] The relative arrangement of the radiation source 3 and the detector 4 of the radiation scanning device of this embodiment is basically the same as that of the above-mentioned embodiment. Specifically, similar to the above-mentioned embodiment, the radiation source 3 includes a plurality of radiation source modules, each of which is arranged around the scanning region and located in a plane, particularly in the same plane, perpendicular to the transport direction of the object 6; the detector 4 includes a plurality of detector groups, each of which is located in another plane, particularly in the same plane, perpendicular to the transport direction of the object 6, and ends of each detector group are connected to each other so as to be arranged around the scanning region; and further, in a combined state of the radiation source 3 and the detector 4, the detector 4 is located inside the radiation source 3 in a direction perpendicular to the transport direction of the object 6. The radiation source 3 and the detector 4 are arranged in a non-closed structure around the scanning region, and the radiation source 3 and the detector 4 at least partially overlap in the transport direction of the object 6, and the detector group of the detector 4 may have any of the structures described in the above-mentioned embodiments, such as a closed square structure, a rectangular structure, a polygonal structure, or an elliptical structure, which open around the scanning region. Different from the above-mentioned embodiments, the radiation source 3 has a non-closed structure around the scanning region, which open below the transmission device, and may have any of the structures described in this embodiment, such as a rectangular structure, a polygonal structure, an elliptical structure, which open below the transmission device.

[0228] As in the previous embodiment, each detector group of the detector 4 in this embodiment is arranged so as to selectively not block the radiation beam of the radiation source module on the same side and to receive radiation from each radiation source module on the other side. Because the radiation source 3 and the detector 4 are both arranged in a ring shape (the radiation source 3 is a half-open ring with an open bottom), the same detector group can be shared by different radiation source modules of the radiation source. Furthermore, radiation from each radiation source module of the radiation source 3 can be detected not only by the detector group on the opposite side but also by the detector group on the other side, so that as much radiation as possible from each radiation source module can be detected by the detector. Therefore, the detector of this embodiment similarly improves image quality and reduces the number of detector groups, thereby reducing device costs.

[0229] Also, similarly to the above embodiment, the detector crystals of each detector group of the detector 4 are optionally arranged at an end of the detector unit along the transport direction of the object 6, adjacent to the edge of the radiation beam of the radiation source module on the same side in the transport direction of the object 6, but not blocking the radiation beam of the radiation source module on the same side. This makes it possible to minimize the covering length of the optical path between the radiation source and the detector, thereby reducing the length of the apparatus.

[0230] As in the previous embodiment, optionally, each radiation source module of the radiation source 3 is arranged so that the radiation beam avoids the detector group on the same side and irradiates the detector crystal of the detector group on the opposite side. Specifically, as in the previous embodiment, the radiation source module can be rotated by a predetermined angle with respect to the target axis to adjust the beam exit angle of the radiation beam from the radiation source module, thereby irradiating the detector crystal at the center position of the radiation beam. Since the detector crystal of the detector is located at the end position of the detector unit in the transport direction of the subject 6 and is arranged adjacent to the edge of the radiation beam of the radiation source on the same side, the radiation source module can be rotated by a very small predetermined angle, for example, 1.5 degrees, to irradiate the detector crystal at the center position of the radiation beam. In this way, adverse effects on imaging caused by the radiation beam being obliquely incident on the surface of the detector crystal can be minimized. As in the previous embodiment, the radiation source module can be rotated about the target axis or another axis, or the beam exit angle of the radiation beam can be adjusted by any other appropriate method described in the previous embodiment.

[0231] In addition, since the radiation source of this embodiment also lacks projection data at the end of the adjacent radiation source module, similar to the previous embodiment, the image processing module of the radiation scanning device of this embodiment is also configured with a data compensation function to compensate for the missing data in the field of view and / or restore the reconstructed image to improve image quality. The image processing module of the radiation scanning device of this embodiment performs image reconstruction in the same manner as the previous embodiment.

[0232] The radiation scanning device of this embodiment has the same advantages as the radiation scanning devices of the above-described embodiments, as well as the following advantages.

[0233] In the radiation scanning device of this embodiment, the radiation source module is not arranged below the transmission device, so the height of the transmission device can be reduced, which makes it convenient to transport the test object to the transmission device. Furthermore, compared to the above-mentioned embodiment in which the radiation source module is also arranged below the transmission device, this embodiment can reduce the cost of the device.

[0234] Although the radiation scanning device of this embodiment does not have a lower radiation source, an upper detector group is still installed at the lower position opposite the radiation source module, and the upper detector group can receive radiation from the radiation source modules on both sides, thereby increasing the corresponding detection data of the radiation from the radiation source modules on both sides, thereby improving the image quality compared to when detector groups are installed only on the opposite sides of each radiation source module.

[0235] Furthermore, although the present embodiment has been described by way of example in which the multiple radiation source modules of the radiation source are arranged in the same plane perpendicular to the transport direction of the subject, the present embodiment can also be applied to a case in which the multiple radiation source modules of the radiation source are arranged in different planes perpendicular to the transport direction of the subject.

[0236] In addition, in this embodiment, an example has been described in which multiple detector groups of detectors are arranged in the same plane in the transport direction of the subject, but the same applies to cases in which multiple detector groups of detectors are arranged in different planes perpendicular to the transport direction of the subject.

[0237] In the above embodiment, the radiation scanning device is described in which the radiation source and the detector surround the scanning area on four sides (top, bottom, left, right). In another embodiment, the present application has a radiation scanning device that is basically the same in structure as the above embodiment, but differs in the arrangement of the radiation source and the detector. Specifically, in this embodiment, when viewed from the direction of transport of the subject, the multiple radiation source modules of the radiation source are arranged in a non-enclosed structure opening on one side of the scanning region to surround the scanning region, and the multiple detector groups of the detector are also arranged in a non-enclosed structure opening on one side of the scanning region to surround the scanning region, the openings of the non-enclosed structures of the detectors are located opposite the openings of the non-enclosed structures of the radiation source, and the multiple detector groups of the detector are fixed in the same plane perpendicular to the direction of transport of the subject, and the multiple radiation source modules of the radiation source are fixed in different planes perpendicular to the direction of transport of the subject. For example, the radiation source module and each detector group of the detector arranged on the side of the opening of the non-enclosed structure of the detector of the radiation source are fixed in the same plane perpendicular to the direction of transport of the subject, and the other radiation source modules of the radiation source are fixed in different planes perpendicular to the direction of transport of the subject.

[0238] The configuration and arrangement of the radiation source of the radiation scanning device according to this embodiment will be described in detail below.

[0239] Similar to the previous embodiment, the radiation source of the radiation scanning device of this embodiment includes multiple radiation source modules, and each radiation source module may be a distributed multi-point source. As a distributed multi-point source, each radiation source module may have multiple target points, and each target point of each radiation source module may generate a radiation beam individually, and each target point may generate a radiation beam in a predetermined time sequence under the control of the control device. The radiation beam may be a fan beam with an opening angle A, as shown in FIG. 3. Of course, the shape of the radiation beam is not limited to a fan beam, and may be a radiation beam of other shapes, such as a cone beam or a parallel beam, and may be specifically configured as needed.

[0240] In the above embodiment, when viewed along the transport direction of the subject, the multiple radiation source modules of the radiation source surround the scanning area on four sides, but in the present embodiment, when viewed along the transport direction of the subject, the multiple radiation source modules of the radiation source are arranged to surround the scanning area on only three sides, that is, they are arranged to surround the scanning area in a non-closed structure that is open to the scanning area side. Specifically, as shown in FIGS. 19 to 21 (FIG. 19 is a three-dimensional schematic diagram of the layout of the radiation source and detector of the radiation scanning device of this embodiment, FIG. 20 is a schematic side view of the radiation source and detector shown in FIG. 19 viewed along the transport direction of the subject, and FIG. 21 is a schematic plan view of the layout of the radiation source and detector shown in FIG. 19), where the radiation source modules on the left and right sides of the scanning region are arranged in the same plane perpendicular to the transport direction of the subject (as shown by the positions of the solid radiation exit ports in FIG. 21), and the radiation source module below the scanning region is arranged in another plane perpendicular to the transport direction of the subject (as shown by the positions of the radiation exit ports with dashed lines in FIG. 21), when viewed from the transport direction of the subject, the radiation source 3 includes radiation source modules 31, 32, and 33 arranged on the left, right, and below the scanning region, respectively, and the radiation source modules 31, 32, and 33 form a non-enclosed structure surrounding the scanning region which opens above the scanning region. In the illustrated embodiment, the radiation source modules are linearly distributed multi-point sources, and the open structure of the radiation source is a right-angled rectangular structure opening above the scanning region. The radiation source modules 31, 32, and 33 of the radiation source 3 are not limited to linearly distributed multi-point sources, and may be arc-shaped, polygonal, or other shapes in other embodiments. The linear, arc-shaped, or polygonal radiation source modules can be arranged or combined as needed to form a rounded rectangular structure, polygonal structure, elliptical structure, or other shape surrounding the scanning region, with the radiation source 3 opening above the scanning region, as viewed in the direction of object transport. Furthermore, as viewed in the direction of object transport, the radiation source modules of the radiation source 3 are not limited to being arranged on the left, right, and bottom of the scanning region. For example, they may be arranged on the top, left, and right sides, or both upper and lower and left sides, or both upper and lower and right sides, depending on the actual application scenario.In the following description of this embodiment, the case where the radiation source modules are provided on the left, right, and bottom sides of the scanning area will be described as an example, but the principles described will also be applicable to cases where the radiation source modules are arranged on any of the other three sides.

[0241] Similar to the previous embodiment, the multiple radiation source modules of the radiation source of this embodiment are also individually detachable from each other, i.e., each radiation source module has its own vacuum cavity for accommodating its respective radiation generating device. The fact that each radiation source module has its own vacuum cavity means that the multiple target points of each radiation source module share one individual vacuum cavity. The spacing between the multiple target points of each radiation source module within the vacuum cavity can be determined by the number of target points and the length of the cavity. According to some embodiments, the number of target points in a single radiation source module may be 192, 264, etc., and the spacing between the target points in a single radiation source module may be 4 mm, 12 mm, etc. The advantage of each radiation source module having its own cavity is that, compared to a radiation source with an integral annular cavity (i.e., all target points of the radiation source are located in the same annular vacuum cavity), the size of the housing of the single radiation source module and the volume of the internal vacuum cavity can be reduced, and the volume and weight of the single radiation source module are reduced, making it convenient to attach and detach the radiation sources. In addition, the use of a separate vacuum cavity for each radiation source module reduces the risk of ignition in the cavity when performing maintenance on the radiation source modules.

[0242] Furthermore, as in the previous embodiment, each radiation source module of the radiation source 3 is provided with a mounting and positioning structure for facilitating the mounting and adjustment of the radiation source module. The mounting and positioning structure allows each radiation source module of the radiation source 3 to be mounted and fixed at a predetermined position in the radiation scanning device. The mounting and positioning structure also allows the radiation source module to be rotated to adjust the beam output angle of the radiation beam. Since the radiation source modules of the radiation source 3 are located at different positions in the radiation scanning device, different mounting methods and mounting and positioning structures may be used. For example, the radiation source modules located on the left and right sides of the scanning area may be mounted in a suspended manner using a device such as an overhead vehicle. The radiation source module located below the scanning area does not conform to the suspended method and may be mounted and fixed using the mounting and positioning structure described in the previous embodiment (such as the mounting and positioning structure shown in FIG. 5 ) or have its beam output angle adjusted.

[0243] Similarly to the above embodiment, the radiation source 3 may be composed of multiple single point sources, and each radiation source module may be a single point source group, with each single point source group including at least two single point sources. Each single point source can individually emit a radiation beam, for example, a fan beam having an opening angle A (as shown in FIG. 3). Each single point source of the radiation source 3 can emit radiation in a predetermined time sequence under the control of a control device of the radiation scanning system. When each radiation source module is a single point source group, the single point source group can be distributed at least over the bottom, left, and right field angles, and further over corner oblique field angles, such as the lower left oblique field angle and the lower right oblique field angle, and can further include the upper left oblique field angle and the upper right oblique field angle, as shown in FIG. 22.

[0244] The arrangement of the detector 4 of the radiation scanning device of this embodiment will be described in detail below. As in the previous embodiment, the detector 4 may include multiple detector groups, which are selectively located in the same plane perpendicular to the transport direction of the subject 6. Also, as in the previous embodiment, the detector group of this embodiment is a detector array including multiple detector units.

[0245] Furthermore, in the above-described embodiment, the multiple detector groups of the detector 4 are arranged to surround the scanning area on four sides, forming a closed structure surrounding the scanning area, as viewed in the direction of subject transport. However, in this embodiment, the detector groups of the detector 4 are arranged to surround the scanning area on only three sides, as viewed along the direction of subject transport. That is, they are arranged to surround the scanning area in an open structure that opens to one side of the scanning area. Specifically, as shown in FIGS. 19 to 21 , the detector 4 includes detector groups 41, 42, and 43 arranged on the left, right, and upper sides of the scanning area, respectively. The ends of the detector groups 41, 42, and 43 are connected to each other to form an open structure that surrounds the scanning area and opens to the lower side of the scanning area. In the example shown in FIGS. 19 to 21 , the detector groups 41, 42, and 43 are linear detector arrays including multiple detector units arranged along a straight line, thereby forming an open rectangular or square structure that opens to the lower side of the scanning area. However, the detector 4 of this embodiment is not limited to the above configuration and may have other configurations. For example, detector 4 may include three relatively long linear detector arrays and two relatively short linear detector arrays, which are arranged alternately around the scanning area and connected at their ends to form a non-closed polygonal structure that opens below the scanning area (as shown in FIG. 23). Detector 4 may also include other numbers of multiple relatively long linear detector arrays and other numbers of multiple relatively short linear detector arrays, which are arranged alternately around the scanning area and connected at their ends to form other non-closed polygonal structures that open below the scanning area. The detector group of detector 4 in this embodiment may also be an arc-shaped detector array, which includes multiple arc-shaped detector arrays arranged around the scanning area and connected at their ends to form a non-closed elliptical structure that opens below the scanning area. The detector group of the detector 4 in this embodiment may be a combination of a linear detector array and an arc-shaped detector array, or form other shapes of non-closed structures that open to the bottom of the scanning area, such as a rounded rectangular structure that opens to the bottom of the scanning area, etc. Here, the structure of the detector unit and the structures of the detector groups in the form of a linear detector array and an arc-shaped detector array are completely the same as those described in the above embodiments.

[0246] 19 to 21, the detector group of detector 4 is not limited to being installed on the left, right, and upper sides of the scanning area, but may be installed, for example, on the lower side, left and right sides, or on both the upper and lower sides and the left side, or on both the upper and lower sides and the right side, as long as the openings of the non-enclosed structures of the radiation sources can be made to face each other. In this embodiment, a case where the detector groups shown in FIGS. 19 to 21 are installed on the left, right, and upper sides of the scanning area will be described as an example, but this embodiment is also applicable to cases where the detector groups are installed on any of the other three sides.

[0247] Furthermore, similar to the above-described embodiments, in some embodiments, each detector group of the detector 4 can be individually attached and detached, thereby improving the maintainability of the detector. Similarly to the above-described embodiments, the multiple detector groups of the detector 4 in this embodiment are configured to be attached and detached by moving along the transport direction of the subject 6. In this way, when the detector groups of the detector 4 are arranged inside the radiation source 3 along a direction perpendicular to the transport direction of the subject 6, the detector groups can be attached and detached, adjusted, and maintained without the need to remove the radiation source, further improving the maintainability of the detector. As in the detector 4 shown in FIGS. 19 to 21 , the detector groups 41, 42, and 43 can be attached and detached by moving parallel to the transport direction of the subject 6, and the detector groups can be attached and detached, adjusted, and maintained without the need to remove the radiation source modules 31, 32, and 33. The detector groups 41, 42, and 43 of the detector 4 can be removed from or attached to their mounting positions by moving them along the transport direction of the subject 6 relative to the mounting positions of the detector groups in the radiation scanning device using the same mounting and fixing structure described in the above embodiments (such as the embodiment shown in FIG. 9 and its variations). For example, similar to the above embodiments, the detector groups 41, 42, and 43 can be attached to or removed from the support frame 5 of the radiation scanning device via detector arms.

[0248] Furthermore, when the open-ended openings of the radiation source or detector face the left or right side of the scanning region, the detector group of detector 4 can be attached or detached by moving along a direction perpendicular to the transport direction of the object. As shown in FIG. 24 , when viewed along the transport direction of the object, the open-ended openings of radiation source modules 31, 32, and 33 of the radiation source face the left side of the scanning region, and the open-ended openings of detector groups 41, 42, and 43 of detector 4 face the right side of the scanning region. In this case, the detector groups 41, 42, and 43 can be attached or detached to or from an attachment position such as support frame 5 along a direction perpendicular to the transport direction of the object, as shown by the arrows in FIG. 24(b). Because no radiation source module is installed on the left side of the scanning region, the radiation source does not interfere with the above-mentioned detector movement, making it easy to detach the detector group. Such a detachable method can employ an attachment / fixing structure that is adapted to attach and detach the detector group along a direction perpendicular to the transport direction of the subject described above, such as the attachment / fixing structure and its variations described with reference to Figures 15 to 17.

[0249] Furthermore, some of the detector groups of the detector 4 may be attached or detached by moving them in the direction of transport of the subject, and other parts may be attached or detached by moving them in a direction perpendicular to the direction of transport of the subject. For example, in the embodiment shown in FIGS. 19 to 21 , if the highest point of the radiation source modules 31, 32 on the left or right side of the scanning region is lower than the detector group 41 above the scanning region, the detector group 41 may be attached or detached by moving it in a direction perpendicular to the direction of transport of the subject. A specific mounting and fixing structure may be the embodiment shown in FIG. 15 or its modified example. Similarly, if the detector groups of the detector 4 are arranged on the left, right, and lower sides of the scanning region, and the lower detector group is lower than the lowest points of the radiation source modules on the left and right sides, the lower detector group may also be attached or detached by moving it in a direction perpendicular to the direction of transport of the subject. A specific mounting and fixing structure may be the embodiment shown in FIG. 16 or its modified example.

[0250] Also, similar to the above embodiment, the multiple detector groups of the detectors are in the same plane perpendicular to the transport direction of the specimen 6 after being mounted, due to their respective mounting surfaces and corresponding mounting reference surfaces (installed in the same plane perpendicular to the transport direction of the specimen 6).

[0251] The relative arrangement of the radiation source 3 and the detector 4 of the radiation scanning device according to this embodiment will be further described below. In this embodiment, the relative arrangement of the radiation source 3 and the detector 4 differs from that of the above-described embodiment. In this embodiment, in a combined state of the radiation source and the detector, the opening of the non-enclosed structure of the radiation source and the opening of the non-enclosed structure of the detector are arranged opposite to each other, multiple detector groups of the detector are fixed in the same plane perpendicular to the transport direction of the subject, and multiple radiation source modules of the radiation source are arranged in multiple planes perpendicular to the transport direction of the subject, for example, the radiation source module of the radiation source arranged on the side of the opening of the non-enclosed structure of the detector and each detector group of the detector are fixed in the same plane perpendicular to the transport direction of the subject, and other radiation source modules of the radiation source are fixed in other planes perpendicular to the transport direction of the subject. The other radiation source modules of the radiation source can be located in another single plane perpendicular to the transport direction of the subject or in other multiple different planes, optionally in another single plane, and this embodiment will be described as an example in which the other radiation source modules are arranged in another single plane perpendicular to the transport direction of the subject (as shown in Figure 21), but the same applies to the case of other multiple different planes.

[0252] In the combined state of the radiation source and the detector, the radiation source may have any of the structures described in the above embodiments, such as a rectangular, polygonal, or elliptical structure opening on one side of the scanning region when viewed along the transport direction of the subject, and the detector may have any of the structures described in the above embodiments, such as a square, rectangular, polygonal, or elliptical structure opening on one side of the scanning region, as long as the openings of the radiation source and the detector structure are arranged opposite each other. Hereinafter, the detailed arrangement of the combined state of the radiation source 3 and the detector 4 will be described using the embodiments shown in Figures 19 to 21 as examples, but the same principle can be applied to any other combination of the radiation source 3 and the detector 4.

[0253] In particular, similar to the above embodiment, based on the combination of the radiation source 3 and the detector 4, in a circular (half-open) arrangement of the detectors, the detector groups 41, 42, and 43 of the detector 4 may be arranged so that they can receive radiation from each radiation source module on the remaining side, allowing multiple radiation source modules of the radiation source to share each detector group of the detector. This reduces the number of detector groups. Furthermore, radiation from the radiation source modules 31 and 32 can be detected not only by the detector groups 42 and 41 on the opposite side, but also by detector groups on other sides other than the detectors on the same side. Radiation from the radiation source module 33 can be received by all the detector groups 41, 42, and 43, so that as many radiation sources as possible can be detected by the detectors. As a result, even if the radiation source modules and detectors are arranged on only three sides of the scanning area, the radiation scanning device of this embodiment can still obtain sufficient detection data for image reconstruction. At the same time, the weight of the device can be reduced by reducing the number of radiation source modules and detector groups, which is advantageous for configuring a lightweight radiation scanning device.

[0254] In particular, the radiation source module 33 of the radiation source 3 and the detector groups 41, 42, and 43 of the detector 4 are arranged in the same plane perpendicular to the transport direction of the subject. This specifically means that the radiation exit port of the radiation source module 33 faces directly toward the detector crystals of each detector group (as shown in FIG. 21). This allows the radiation beam of the radiation source module 33 to cover more detector crystals, which is advantageous for obtaining more detection data and improving image quality.

[0255] Furthermore, particularly similar to the detector groups in the above-described embodiment, when viewed from the transport direction of the subject, i.e., in a direction perpendicular to the transport direction of the subject, the detector groups 41, 42 on the same side as the other radiation source modules 31, 32 of the detector 4 are disposed between the other radiation source modules 31, 32 of the radiation source 3 and the scanning region, respectively, so that the other radiation source modules 31, 32 at least partially overlap the detector groups 41, 42 on the same side in the transport direction of the subject (as shown in FIG. 21 ). This reduces the length of the apparatus covered by the optical path between the radiation source and the detector, thereby reducing the overall length of the apparatus.

[0256] Also, similar to each detector group in the above embodiment, when the detector groups 41 and 42 at least partially overlap with the radiation source modules 31 and 32 in the transport direction of the subject, the detector groups 41 and 42 are configured to avoid the radiation beams of the radiation source modules 31 and 32 on the same side, respectively, and to receive radiation from all remaining radiation source modules other than the radiation source module on the same side.

[0257] Furthermore, similar to the above embodiment, the detector crystals of each detector group of the detector 4 are arranged at the end of the detector unit along the transport direction of the object to be detected, and the detector groups 41, 42 of the detector 4 on the same side as the other radiation source modules 31, 32 are arranged adjacent to the radiation beam edges of the radiation source modules 31, 32 on the same side in the transport direction of the object to be detected, but not to block the radiation beams of the radiation source modules 31, 32 on the same side. This allows the radiation source 3 and the detector 4 to overlap to the maximum extent in the transport direction of the object to be detected, and the length of the apparatus covered by the optical path between the radiation source and the detector can be made as small as possible, thereby reducing the overall length of the apparatus.

[0258] Furthermore, particularly, similar to the previous embodiment, the radiation source modules 31 and 32 of the radiation source 3 are arranged so that the radiation beams irradiate the detector crystals of the detector groups 41 and 42 on the opposite side, avoiding the detector groups 41 and 42 on the same side. Furthermore, similar to the previous embodiment, the radiation source modules 31 and 32 can be rotated by a predetermined angle about their respective target axes to adjust the beam exit angles of their respective radiation beams, thereby irradiating the detector crystals on the opposite sides at the center positions of their respective radiation beams. Because the detector crystals of the detectors are located at the end positions of the detector units in the transport direction of the subject and adjacent to the edge of the radiation beam of the radiation source on the same side, the radiation source modules can be rotated by a very small predetermined angle, for example, 1.5 degrees, to irradiate the detector crystals at the center positions of the radiation beams. In this way, adverse effects on imaging caused by the radiation beams being obliquely incident on the surfaces of the detector crystals can be minimized. Also, similar to the previous embodiment, the radiation source modules can be rotated about the target axis or another axis, or the beam exit angles of the radiation beams can be adjusted by any other appropriate method described in the previous embodiment.

[0259] Similarly to the previous embodiment, projection data may also be missing at the ends of adjacent radiation source modules of the radiation source in this embodiment. For example, in the embodiment shown in Figures 19 to 21, the distance between the target points at the adjacent ends of radiation source modules 31 and 33 and at the adjacent ends of radiation source modules 33 and 32 may be greater than the distance between the target points within each radiation source, resulting in missing projection data at these ends. Therefore, similar to the previous embodiment, the image processing module of the radiation scanning device in this embodiment is also configured with a data compensation function that can improve image quality by compensating for missing data in the field of view and / or repairing the reconstructed image. The image processing module of the radiation scanning device in this embodiment performs image reconstruction in the same manner as the previous embodiment.

[0260] Of course, according to other embodiments, the radiation source modules 31, 32 and the radiation source module 33 are arranged in different planes perpendicular to the transport direction of the object, in particular so that adjacent ends of the radiation source modules 31, 33 and / or adjacent ends of the radiation source modules 33, 32 can be arranged to overlap along the transport direction of the object, such that the target points at adjacent ends of adjacent radiation source modules 31, 33 or 32, 33 overlap or the spacing between the target points is equal to or smaller than the spacing between the target points within each radiation source. In this case, there is no loss of projection data, and therefore there is no need to perform image reconstruction using the data correction function of the image processing module accordingly.

[0261] The radiation scanning device of this embodiment has the same advantages as the radiation scanning device of the above embodiment, as well as the following advantages.

[0262] The radiation source and detector of this embodiment surround the scanning area on only three sides, and compared to a case where the scanning area is surrounded on four sides (which may be the radiation source or the detector, or both), sufficient data can be acquired to perform image reconstruction, thereby reducing the cost and weight of the device and providing a lightweight radiation scanning device.

[0263] In addition, in this embodiment, the radiation source modules on one side of the scanning area can be individually positioned facing the detector crystals of the detector, so that the radiation from the radiation source modules can be covered by more detector units, which is advantageous in increasing the amount of data and improving the image quality.

[0264] The above describes a radiation scanning device in which the radiation sources surround the scanning area on four sides (top, bottom, left, right) or any three of those sides. However, in other embodiments, the radiation sources may be arranged to surround the scanning area on only any two of the four sides (top, bottom, left, right).

[0265] The above describes the mounting and positioning structure of each radiation source module used in the radiation source. However, the mounting and positioning structure is not limited to being used in the radiation scanning device of the present application, and may be used in other appropriate radiation scanning devices.

[0266] The above describes various mounting and fixing structures used for detector groups, but the above mounting and fixing structures are not limited to being used in the radiation scanning device of the present application, and may be used in other appropriate radiation scanning devices, and the mounting and fixing structures of each embodiment may be used individually or in combination in a single radiation scanning device.

[0267] The above is only a preferred embodiment of the present application and is not intended to limit the present application. Those skilled in the art can make various modifications and changes to the embodiments of the present application. Any modifications, equivalent replacements, improvements, etc. made within the inventive concept and principles of the present application shall be included within the protection scope of the present application.

[0268] As those skilled in the art will understand, the above embodiments are illustrative and not restrictive. Different technical features appearing in different embodiments can be combined to achieve beneficial effects. Those skilled in the art can understand and implement other variations of the disclosed embodiments after studying the drawings, the specification, and the claims. In the claims, the term "comprises" does not exclude other devices or steps, and is intended to include one or more items and be used interchangeably with "one or more items" when the item is not modified by a quantifier. The terms "first" and "second" are intended to indicate names, not to indicate any particular order. Any reference numerals in the claims do not limit the scope of the claims. The functions of multiple parts recited in the claims may be realized by a single hardware or software module. The fact that some technical features appear in different dependent claims does not mean that these technical features cannot be combined to achieve beneficial effects.

Claims

1. 1. A radiation scanning device, comprising: a transmission device for transporting the subject through a scanning region of the radiation scanning device; a radiation source including a plurality of radiation source modules each having at least one radiation source point for emitting a radiation beam, the plurality of radiation source modules being arranged to surround the scanning region in a non-enclosed structure that is open on only one of four sides, i.e., top, bottom, left, and right, of the scanning region, as viewed along a transport direction of the subject; a detector including a plurality of detector groups arranged to surround the scanning region in a non-closed structure, the ends of which are connected to each other and which are open only on one of four sides (top, bottom, left, and right) of the scanning region, when viewed along the transport direction of the subject, and which detects radiation transmitted through the subject during scanning; an opening of the non-enclosed structure of the radiation source and an opening of the non-enclosed structure of the detector are disposed opposite to each other; a plurality of detector groups of the detector are fixed in the same plane perpendicular to a transport direction of the object, and a plurality of radiation source modules of the radiation source are arranged in a plurality of different planes perpendicular to the transport direction of the object, the radiation source module of the radiation source located on the open side of the non-enclosed structure of the detector and the plurality of detector groups of the detector are fixed in the same plane perpendicular to the transport direction of the subject, and other radiation source modules of the radiation source are fixed in other planes perpendicular to the transport direction of the subject; Radiation scanning device.

2. another radiation source module of the radiation source is fixed in another same plane perpendicular to the transport direction of the object; 2. A radiation scanning device according to claim 1.

3. the plurality of radiation source modules are individually detachable from one another; 3. A radiation scanning device according to claim 2.

4. each of the plurality of radiation source modules is a distributed multi-point source, and the plurality of distributed multi-point sources are respectively arranged on three sides of the scanning region when viewed along the transport direction of the object, to form a non-closed structure surrounding the scanning region and having one side open; The radiation scanning device according to any one of claims 1 to 3.

5. The distributed multi-point source is formed in a linear, arc-shaped, polygonal, or any combination thereof so that the radiation source is formed as a right-angled rectangle, a rounded rectangle, a polygon, or an elliptical structure opening on one side of the scanning region when viewed from the transport direction of the subject.

5. A radiation scanning device according to claim 4.

6. each of the plurality of radiation source modules is a single point source group, and each single point source group includes at least two single point sources; The radiation scanning device according to any one of claims 1 to 3.

7. Each radiation source module has a separate cavity for housing a respective radiation generating device. The radiation scanning device according to any one of claims 1 to 3.

8. each radiation source module cavity includes a separate vacuum cavity for accommodating multiple target points; 8. A radiation scanning device according to claim 7.

9. the spacing between the target points within each radiation source module is smaller than the spacing between the target points at the ends of adjacent radiation source modules; 9. A radiation scanning device according to claim 8.

10. an attachment and positioning structure is provided in each cavity of the radiation source module for attaching and positioning the radiation source module and for rotating the radiation source module to adjust the beam output angle of the radiation beam; 8. A radiation scanning device according to claim 7.

11. Each detector group is a detector array including a plurality of detector units, and the detector array includes a linear detector array, an arc detector array, or a combination thereof. The radiation scanning device according to any one of claims 1 to 3.

12. Each detector group is a linear detector array, and the detector includes three linear detector arrays, which are respectively arranged on three sides of the scanning area to form a rectangular or square structure opening on one side of the scanning area.

12. A radiation scanning device according to claim 11.

13. each detector group is a linear detector array, the detectors including a plurality of first linear detector arrays and a plurality of second linear detector arrays, the second linear detector arrays being shorter than the first linear detector arrays, the plurality of first linear detector arrays and the plurality of second linear detector arrays being alternately arranged around the scanning area to form a polygonal structure opening on one side of the scanning area; 12. A radiation scanning device according to claim 11.

14. Each detector group of the detectors is individually detachable from each other.

12. A radiation scanning device according to claim 11.

15. The detector group of the detectors is configured to be attached and detached by moving perpendicularly or parallel to the transport direction of the subject.

15. A radiation scanning device according to claim 14.

16. each detector group of the detectors includes a detector arm, the radiation scanning device includes a support frame fixed to a mounting base of the radiation scanning device, and the detector groups are attached to or detached from the support frame via the detector arms; 16. A radiation scanning device according to claim 15.

17. the detector is disposed between the radiation source and the scanning region when viewed from a transport direction of the subject; along the transport direction of the object, the other radiation source module at least partially overlaps with the detector group on the same side. The radiation scanning device according to any one of claims 1 to 3.

18. a detector group on the same side as the other radiation source module of the detectors is configured to avoid radiation beams of the radiation source modules on the same side and to receive radiation beams of all remaining radiation source modules on the sides other than the radiation source module on the same side; 18. A radiation scanning device according to claim 17.

19. each detector unit of the detector group includes a detector crystal for receiving radiation transmitted through the object during scanning, and the detector crystal is disposed at an end of the detector unit along a transport direction of the object; a detector crystal of a detector group on the same side of the detector as the other radiation source module is positioned adjacent to the radiation beam edge of the radiation source module on the same side in the transport direction of the object but not blocking the radiation beam; 18. A radiation scanning device according to claim 17.

20. the other radiation source module of the radiation source is arranged so that the radiation beam avoids the detector group on the same side and irradiates the detector crystal of the detector group on the opposite side; 20. A radiation scanning device according to claim 19.

21. the other radiation source module is configured to rotate about a target axis so as to irradiate a detector crystal of an opposite detector group at a central position of the radiation beam; 21. A radiation scanning device according to claim 20.

22. further comprising an image processing module, the image processing module being configured to perform data compensation and / or reconstruction image restoration for missing projection data at an end of the radiation source module to obtain a complete reconstructed image. The radiation scanning device according to any one of claims 1 to 3.

23. the image processing module is configured to perform image reconstruction by an iterative method, an image region inpainting method, or a combination of both; 23. A radiation scanning device according to claim 22.

Images