Imaging method of CT imaging system

Abstract

An embodiment of the present invention provides an imaging method of a CT imaging system, which relates to the field of radiation scanning technology. The CT imaging system includes: an imaging channel; M distributed ray sources, at least one of which includes q target points; N detectors; the q target points included in at least one of the M distributed ray sources are arranged at intervals along a first straight line, and the first straight line is arranged obliquely relative to a first direction. The imaging method includes: placing an object to be imaged in an imaging channel; controlling the q target points of at least one distributed ray source to emit a ray beam to form an imaging area; using at least one detector to detect rays emitted from at least one distributed ray source and passing through the object to be imaged, and generating projection data based on the detected rays; generating a computerized tomography image of the object to be imaged based on the projection data. The beam emission time interval is determined based on the inclination angle of the extension direction of the first straight line relative to the first direction.

Description

Technical Field

[0001] The present invention relates to the field of radiation scanning technology, and more specifically, to an imaging method of a CT imaging system. Background Art

[0002] CT (Computed Tomography) scanning system is a non-destructive testing technology widely used in biomedicine, image-guided intervention, security inspection, industrial and agricultural production, geophysics and petroleum exploration, etc. It has fast imaging speed and high precision, and can fully present the three-dimensional information of the inspected part.

[0003] With the continuous expansion of CT application scenarios, the demand for fast CT has emerged in more and more fields. For example, CT scanning of active tissues and organs in clinical diagnosis. Spiral CT has greatly reduced the scanning time by relying on slip ring technology, but the rotation speed of the slip ring has basically reached its limit, and it is difficult to further shorten the scanning time; the emergence of multi-source spiral CT has further shortened the CT scanning time. Multi-source spiral CT has obvious advantages in scanning speed. The more sources there are, the shorter the scanning time. However, multi-source systems also bring challenges such as high costs and huge amounts of data.

[0004] In recent years, the emergence of distributed light sources has made it possible to further shorten the scanning time. Distributed light sources avoid the use of slip rings and can be imaged by simply exposing in sequence, completely avoiding mechanical movement. However, existing distributed light source scanning solutions generally have problems such as limited angle scanning, data truncation, and motion artifacts. These problems increase the difficulty of data processing and image reconstruction, and also affect the imaging quality.

[0005] It should be noted that the above information disclosed in this section is only used for understanding the background of the inventive concept of the present invention, and therefore, the above information may include information that does not constitute the prior art. Summary of the invention

[0006] In view of at least one aspect of the above technical problems, the present invention provides an imaging method of a CT imaging system, the CT imaging system comprising: an imaging channel, at least a portion of which extends along a first direction; M distributed ray sources, the M distributed ray sources are arranged along the circumference of the imaging channel, at least one of the distributed ray sources comprises q target points, M and q are both positive integers greater than or equal to 2; and N detectors, the N detectors are arranged along the circumference of the imaging channel, N is a positive integer greater than or equal to M, wherein the q target points comprised by at least one of the M distributed ray sources are arranged at intervals along a first straight line, and the extension of the first straight line The extension direction is inclined relative to the first direction, and the imaging method includes: placing the object to be imaged in the imaging channel and controlling q target points of at least one distributed ray source among the M distributed ray sources to emit ray beams according to a predetermined beam-emitting sequence and a predetermined beam-emitting time interval to form an imaging area; using at least one of the detectors to detect rays emitted from the at least one distributed ray source and passing through the object to be imaged, and generating projection data based on the detected rays; and generating a computerized tomography image of the object to be imaged based on the projection data, wherein the beam-emitting time interval is determined based on the inclination angle of the extension direction of the first straight line relative to the first direction.

[0007] According to some exemplary embodiments, the imaging method further includes: controlling the object to be imaged to move at a predetermined moving speed in the imaging channel.

[0008] According to some exemplary embodiments, the beam emission time interval is further determined based on a distance between two adjacent target points among the q target points and the moving speed.

[0009] According to some exemplary embodiments, when the object to be imaged moves at a predetermined moving speed, the beam emission time interval satisfies: within the imaging time, along the first direction, the q target points and the object to be imaged are in a relatively stationary state.

[0010] According to some exemplary embodiments, controlling q target points of at least one of the M distributed ray sources to emit ray beams according to a predetermined beam emitting order and a predetermined beam emitting time interval includes: when the object to be imaged is located in the imaging area, controlling the kth target point of at least two of the M distributed ray sources to emit beams simultaneously, 1≤k≤q.

[0011] According to some exemplary embodiments, the controlling q target points of at least one of the M distributed ray sources to emit ray beams according to a predetermined beam emitting order and a predetermined beam emitting time interval includes: when the object to be imaged is located in the imaging area, controlling the multiple target points to emit beams according to the following beam emitting order: when j takes values ​​from 1 to q-1 in sequence, the j-th target point of the M distributed ray sources emits beams at the same time; then, the j+1-th target point of the M distributed ray sources emits beams at the same time, wherein, in the first direction, the j+1-th target point is located on the downstream side of the j-th target point.

[0012] According to some exemplary embodiments, the imaging method includes: determining the beam-emitting time interval based on the following relationship: t=s*cosθ / v, wherein t is the beam-emitting time interval, s is the interval distance between two adjacent target points among the q target points, v is the moving speed, and θ is the inclination angle of the q target points relative to the first direction.

[0013] According to some exemplary embodiments, controlling q target points of at least one of the M distributed ray sources to emit ray beams according to a predetermined beam emitting order and a predetermined beam emitting time interval includes: when the object to be imaged is located in the imaging area, controlling the kth target point of at least two of the M distributed ray sources to emit beams in time, 1≤k≤q.

[0014] According to some exemplary embodiments, the controlling q target points of at least one of the M distributed ray sources to emit ray beams according to a predetermined beam emitting order and a predetermined beam emitting time interval includes: when the object to be imaged is located in the imaging area, controlling multiple target points to emit beams according to the following beam emitting order: when j takes values ​​from 1 to q-1 in sequence, the j-th target point of the M distributed ray sources emits beams in sequence and in time; then, the j+1-th target point of the M distributed ray sources emits beams in sequence and at the same time, wherein, in the first direction, the j+1-th target point is located on the downstream side of the j-th target point.

[0015] According to some exemplary embodiments, the imaging method includes: determining the beam-emitting time interval based on the following relationship: t=s*cosθ / (M*v), wherein t is the beam-emitting time interval, s is the interval distance between two adjacent target points among the q target points, v is the moving speed, and θ is the inclination angle of the q target points relative to the first direction.

[0016] According to some exemplary embodiments, the beam emission time interval reaches the microsecond level; and / or the single acquisition time of the detector is 30-150 microseconds; and / or the imaging resolution of the imaging method is 1-30 milliseconds.

[0017] According to an embodiment of the present invention, by adopting a predetermined beam-emission sequence and time interval determined based on the tilt angle of the target relative to the first direction, accurate timing control and data acquisition of the imaging process are achieved. The tilted target and the precise beam-emission time interval can provide richer angle data, increase data redundancy, and facilitate subsequent image reconstruction and artifact reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0019] Figure 1 is a schematic structural diagram of a ray scanning imaging system according to some exemplary embodiments of the present invention;

[0020] Figure 2 is a schematic structural diagram of a CT imaging system based on a three-segment coplanar scanning structure according to some exemplary embodiments of the present invention;

[0021] Figure 3A According to some exemplary embodiments of the present invention, Figure 2 A three-dimensional schematic diagram of a CT imaging system, wherein the arrangement of multiple distributed ray sources and multiple detectors is schematically shown;

[0022] Figure 3B According to some exemplary embodiments of the present invention, Figure 2 Schematic diagram of the imaging optical path of the CT imaging system;

[0023] Figure 4A is a plan view schematically illustrating an arrangement of distributed ray sources and detectors included in a CT imaging system according to some exemplary embodiments of the present invention, wherein two distributed ray sources and two detectors are schematically illustrated;

[0024] Figure 4B is a plan view schematically illustrating an arrangement of distributed ray sources and detectors included in a CT imaging system according to some exemplary embodiments of the present invention, wherein five distributed ray sources and five detectors are schematically illustrated;

[0025] Figure 4C is a plan view schematically illustrating an arrangement of distributed ray sources and detectors included in a CT imaging system according to some exemplary embodiments of the present invention, wherein a plurality of distributed ray sources and a plurality of detectors are schematically illustrated;

[0026] Figure 5A three-dimensional schematic diagram of a CT imaging system according to some exemplary embodiments of the present invention is shown, wherein the detector includes two types of detectors;

[0027] Figure 6 According to some exemplary embodiments of the present invention, Figure 5 Schematic diagram of the imaging optical path of the CT imaging system;

[0028] Figure 7 is a schematic diagram of an imaging optical path of a CT imaging system according to some other exemplary embodiments of the present invention;

[0029] Fig. 8A is a schematic plan view schematically illustrating an arrangement of distributed ray sources and detectors included in a CT imaging system according to some other exemplary embodiments of the present invention, wherein two distributed ray sources and two detectors are schematically illustrated;

[0030] Figure 8B is a schematic plan view schematically illustrating an arrangement of distributed ray sources and detectors included in a CT imaging system according to some other exemplary embodiments of the present invention, wherein five distributed ray sources and five detectors are schematically illustrated;

[0031] Figure 8C is a schematic plan view schematically illustrating an arrangement of distributed ray sources and detectors included in a CT imaging system according to some other exemplary embodiments of the present invention, wherein a plurality of distributed ray sources and a plurality of detectors are schematically illustrated;

[0032] Fig.8D A schematic diagram showing an arrangement of a distributed ray source and a second sub-detector according to some embodiments of the present invention;

[0033] Fig. 8E A schematic diagram showing an arrangement of distributed ray sources and second sub-detectors according to some other embodiments of the present invention;

[0034] Fig. 9A A schematic diagram showing a layout design of densely arranged detectors according to some embodiments of the present invention;

[0035] Fig. 9B A schematic diagram showing a layout design of sparsely arranged detectors according to some other embodiments of the present invention;

[0036] Fig. 9C A schematic diagram showing a layout design of a mixed arrangement of detectors according to some further embodiments of the present invention;

[0037] Fig. 10A A schematic diagram showing the ray angle coverage in a CT imaging system according to some embodiments of the present invention is shown;

[0038] Fig. 10B A schematic diagram showing the ray angle coverage range in a CT imaging system according to some other embodiments of the present invention;

[0039] Fig.11A A schematic diagram showing an effective imaging area in a CT imaging system according to some embodiments of the present invention;

[0040] Fig. 11B A schematic diagram showing an effective imaging area in a CT imaging system according to some other embodiments of the present invention;

[0041] Fig.12 is a stereoscopic schematic diagram of a CT imaging system according to some exemplary embodiments of the present invention, wherein a target point of a distributed ray source is arranged obliquely;

[0042] Fig.13A is a schematic diagram of a distributed ray source of a CT imaging system according to some exemplary embodiments of the present invention;

[0043] Fig. 13B is a schematic diagram of a distributed ray source of a CT imaging system according to some other exemplary embodiments of the present invention;

[0044] FIG. 13C to FIG. 13E Schematic diagrams showing the arrangement of the distributed ray source and the second sub-detector according to some embodiments of the present invention are shown respectively, wherein: Fig. 13C It shows that the second sub-detector is arranged on both sides of the distributed ray source. Fig.13D It shows that a second sub-detector is arranged on the upper side of the distributed ray source. Fig.13E It is shown that a second sub-detector is arranged on the lower side of the distributed ray source;

[0045] Fig.14A shows a schematic diagram showing a second sub-detector arrangement according to some embodiments of the present invention;

[0046] Fig. 14B A schematic diagram showing an arrangement of second sub-detectors according to some other embodiments of the present invention;

[0047] Fig.15 A flow chart showing an imaging method of a CT imaging system according to some exemplary embodiments of the present invention is shown;

[0048] Fig.16 A schematic diagram of a projection surface of a CT imaging system with multiple target points emitting beams simultaneously according to some exemplary embodiments of the present invention is shown;

[0049] Fig.17A schematic diagram of a projection surface of multi-target time-sharing beam output of a CT imaging system according to some embodiments of the present invention is shown;

[0050] Fig.18A It is an image obtained by using an imaging system and an imaging method in the related art;

[0051] Fig.18B is an image obtained by using the imaging system and imaging method provided by the embodiments of the present invention; and

[0052] Fig.19 A block diagram of an electronic device suitable for implementing the imaging method according to an embodiment of the present invention is schematically shown. DETAILED DESCRIPTION

[0053] Below, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of concepts of the present invention.

[0054] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

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

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

[0057] It should be noted that in this article, computed tomography (also known as CT) imaging refers to the use of radiation to perform tomographic scanning on the object to be imaged, and the analog signal received by the detector is converted into a digital signal. The attenuation coefficient of each pixel is calculated by an electronic computer, and the image is reconstructed, thereby displaying the tomographic structure of each part of the object to be imaged.

[0058] Below, taking the CT scanning imaging system for luggage as an example, the embodiment of the present invention is described in detail. It should be understood that the embodiment of the present invention is not limited to the CT scanning imaging scene of luggage, and it can be applied to various scanning imaging scenes. For example, it can be applied to scanning imaging scenes including various different inspection objects, including but not limited to vehicle scanning imaging, luggage / package scanning imaging, human or animal scanning imaging, organ / tissue scanning imaging, small object scanning imaging, large object scanning imaging such as containers, etc. It should be noted that the description of the scanning imaging scene here is not an exhaustive description, and the following exemplary description should not be understood as limiting the scope of protection of the present invention.

[0059] Figure 1 is a schematic diagram of the structure of a ray scanning imaging system according to some exemplary embodiments of the present invention. Figure 1 In the figure, a CT imaging system based on X-ray scanning is schematically shown as an example of the X-ray scanning imaging system. Figure 1As shown, the CT imaging system according to this embodiment includes: a gantry 20, a conveying mechanism 40, a controller 50, a data processing device 60 (such as a computer), an imaging channel 80, etc. The gantry 20 includes a radiation source 10 that emits X-rays for inspection, such as an X-ray machine, and a detection and acquisition device 30. The imaging channel 80 extends along a first direction z, and the imaging channel 80 is used to place an object to be imaged 70 during the imaging process. For example, at least a portion of a carrying device can be arranged in the imaging channel 80, and the object to be imaged 70 can be placed on the carrying device. During the scanning process, the object to be imaged 70 can be placed still in the imaging area. For another example, at least a portion of the conveying mechanism 40 is placed in the imaging channel 80. The conveying mechanism 40 carries the object to be imaged (such as checked luggage) 70 through the scanning area between the radiation source 10 of the gantry 20 and the detection and acquisition device 30. The conveying mechanism 40 can drive the object to be imaged 70 to move along the first direction z, and the rays emitted by the radiation source 10 can penetrate the object to be imaged 70, and CT scanning is performed on the object to be imaged 70. The detection and acquisition device 30 includes, for example, a detector and a data acquisition device with an integral module structure, such as a flat panel detector, for detecting the rays penetrating the object to be imaged 70, obtaining analog signals, and converting the analog signals into digital signals, thereby outputting the projection data of the object to be imaged 70 for the X-rays. The controller 50 is used to control the various parts of the entire system to work synchronously. The data processing device 60 is used to process the data collected by the data acquisition device, process and reconstruct the data, and output the results.

[0060] like Figure 1 As shown, the ray source 10 is placed on one side of the object 70 to be imaged, and the detection and acquisition device 30 is placed on the other side of the object 70 to be imaged, including a detector and a data acquisition device, which is used to obtain the transmission data and / or multi-angle projection data of the object 70 to be imaged. The data acquisition device includes a data amplification and shaping circuit, which can work in a (current) integration mode or a pulse (counting) mode. The data output cable of the detection and acquisition device 30 is connected to the controller 50 and the data processing device 60, and the collected data is stored in the data processing device 60 according to the trigger command.

[0061] In an embodiment of the present invention, a ray scanning imaging module may be deployed in the data processing device 60, and an image recognition model or a target recognition model may be deployed in the ray scanning imaging module. The ray scanning imaging module may use the image recognition model or the target recognition model to recognize the collected field data (e.g., ray scanning images), and the recognition may include target detection, for example, detecting the target object or the object of interest in the ray scanning image. For example, the target object or the object of interest may be various types of contraband. It should be understood that the specific category of the target object or the object of interest depends on the scanning imaging site arranged by the ray scanning imaging system, or in other words, the specific category of the target object or the object of interest is determined by the user of the ray scanning imaging system according to the specific scanning imaging needs, and it can be dynamically adjusted according to the scanning imaging needs.

[0062] In the embodiment of the present invention, the ray source 10 may be, for example, an X-ray machine, and a suitable X-ray machine target size may be selected according to the imaging resolution. In other embodiments, an X-ray machine may not be used, but a linear accelerator may be used to generate an X-ray beam.

[0063] The detection and acquisition device 30 includes an X-ray detector and a data acquisition circuit. The X-ray detector may be a solid detector, a gas detector or other detectors, but the embodiments of the present invention are not limited thereto. The data acquisition circuit includes a readout circuit, an acquisition trigger circuit, and a data transmission circuit.

[0064] The combination of the controller 50 and the data processing device 60 includes, for example, a computer device installed with a control program and a data processing program, which is responsible for completing the control of the operation process of the CT imaging device, including mechanical rotation, electrical control, safety interlock control, etc., reconstructing CT images from projection data, training image recognition models or target recognition models, and using the trained image recognition models or target recognition models to recognize X-ray scanning images, etc.

[0065] Further, the embodiment of the present invention is described in detail by taking a CT imaging system with a three-segment scanning structure as an example. It should be understood that the following CT imaging system with a three-segment coplanar scanning structure is only an exemplary CT imaging system structure for the convenience of description. Those skilled in the art should understand that the number and position of the ray source and the detector can be adjusted according to specific needs to adapt to objects of different sizes and shapes to be imaged.

[0066] Figure 2 is a schematic structural diagram of a CT imaging system based on a three-segment coplanar scanning structure according to some exemplary embodiments of the present invention. Figure 3A According to some exemplary embodiments of the present invention, Figure 2A three-dimensional schematic diagram of a CT imaging system is shown, which schematically shows the arrangement of multiple distributed ray sources and multiple detectors. Figure 3B According to some exemplary embodiments of the present invention, Figure 2 Schematic diagram of the imaging optical path of the CT imaging system. Figure 4A is a plan view schematically illustrating an arrangement of distributed ray sources and detectors included in a CT imaging system according to some exemplary embodiments of the present invention, wherein two distributed ray sources and two detectors are schematically illustrated; Figure 4B is a plan view schematically illustrating an arrangement of distributed ray sources and detectors included in a CT imaging system according to some exemplary embodiments of the present invention, wherein five distributed ray sources and five detectors are schematically illustrated; Figure 4C It is a plan view schematically illustrating the arrangement of distributed ray sources and detectors included in a CT imaging system according to some exemplary embodiments of the present invention, wherein a plurality of distributed ray sources and a plurality of detectors are schematically illustrated.

[0067] Combined with reference Figures 1 to 4C In some exemplary embodiments, the ray source 10 of the CT imaging system 100 may include a plurality of distributed ray sources, for example, M distributed ray sources, where M is a positive integer greater than or equal to 2. Figures 2 to 3B In the exemplary embodiment shown, M=3, that is, 3 distributed ray sources are provided. Figure 4A In the exemplary embodiment shown, M=2, that is, two distributed ray sources are provided. Figure 4B In the exemplary embodiment shown, M=5, that is, 5 distributed ray sources are provided. Figure 4C In the exemplary embodiment shown, M is a plurality, that is, a plurality of distributed ray sources are provided. In this document, for the convenience of description, the M distributed ray sources are numbered as a first distributed ray source 101, a second distributed ray source 102, a third distributed ray source 103, ..., an Mth distributed ray source 10M.

[0068] In an embodiment of the present invention, a distributed ray source includes multiple targets (also called focal points). For example, multiple X-ray targets can be arranged at a high density in a vacuum chamber of a ray tube. Compared with a traditional single ray source, a distributed ray source has multiple independent ray emission points, which can work independently and can be controlled individually. For example, the distributed X-ray source developed by the applicant of the present invention can integrate hundreds of ray targets in a ray tube, and each target can be independently controlled and quickly switched as required. For example, the emission of each target can be precisely regulated, including parameters such as the intensity and emission time of the ray, so that when performing CT scanning, the output of the ray can be flexibly adjusted according to different scanning parts, object density and other factors, so as to obtain a better quality image. For example, the intensity distribution of the X-ray beam can be modulated by controlling the ray intensity of different targets to meet the imaging requirements of different objects. For another example, by using a distributed ray source with multiple targets, fast scanning imaging capabilities can be achieved. Since multiple ray targets are provided, the distributed ray source can scan the target object simultaneously or quickly in sequence from multiple different positions, greatly improving the scanning speed. Compared with traditional CT scanning methods, it is possible to obtain complete image information of an object in a shorter time, which is of great significance for scenarios that require rapid imaging, such as medical emergency and security inspection. For another example, high-quality imaging effects can be achieved, and the coordinated work of multiple targets and precise control capabilities enable distributed radiation sources to provide higher-resolution and lower-noise images. When imaging complex objects or tiny structures, the internal structure and details of the object can be presented more clearly, providing more accurate information for doctors' diagnosis or other application scenarios.

[0069] Combined with reference Figures 1 to 4C In some exemplary embodiments, the detection and acquisition device 30 of the CT imaging system 100 may include a plurality of detectors, for example, N detectors, where N is a positive integer greater than or equal to 2. For example, N is a positive integer greater than or equal to M. Figures 2 to 3B In the exemplary embodiment shown, N=3, that is, 3 detectors are provided. Figure 4A In the exemplary embodiment shown, N=2, that is, 2 detectors are provided. Figure 4B In the exemplary embodiment shown, N=5, that is, 5 detectors are provided. Figure 4C In the exemplary embodiment shown, N is a plurality, that is, a plurality of detectors are provided. In this document, for the convenience of description, the N detectors are numbered as the first detector 301, the second detector 302, the third detector 303, ... the Nth detector 30N.

[0070] Reference Figures 2 to 4CIn some exemplary embodiments, among the M distributed ray sources, at least one distributed ray source includes q target points 1011, where q is a positive integer greater than or equal to 2. For example, the M distributed ray sources each include more than 2 target points. Figure 2 In the illustrated embodiment, q=11, i.e., a distributed ray source includes 11 target points. In this document, for the convenience of description, the q target points 1011 are numbered as the first target point 111, the second target point 112, the third target point 113, ... the qth target point 11q. Exemplarily, the q target points are configured to be activated in a predetermined order to emit rays.

[0071] It should be understood that the 2, 3 or 5 distributed ray sources and 2, 3 or 5 detectors herein are only exemplary embodiments and should not be understood as limiting the number of distributed ray sources and detectors in the embodiments of the present invention. In other embodiments, the CT imaging system may include a smaller number of distributed ray sources and detectors, such as 4, or a larger number of distributed ray sources and detectors, such as 6, 8, 10 or more. When more than 2 distributed ray sources and detectors are provided, rays can be emitted and received simultaneously or sequentially from different angles and positions, thereby improving the speed and resolution of imaging. Alternatively, 3, 4 or 5 distributed ray sources and detectors are provided, and the combination of more than 3 distributed ray sources and detectors can provide a more comprehensive and detailed scan for the imaging of complex objects. For another example, 6 distributed ray sources and detectors are provided, which can cover rays in a larger range, and have significant advantages for the imaging of large objects or specific application scenarios requiring high resolution. In some cases, more than 8 distributed ray sources and detectors can be set. The configuration of more than 8 distributed ray sources and detectors can achieve more complex scanning modes and multi-angle imaging, providing richer image information for security inspection scenes, doctors' diagnoses and researchers' analysis. It should be understood that as the number of distributed ray sources increases, the CT imaging system can achieve more sophisticated imaging, and the observation of tiny structures and high-precision detection tasks will become more handy. In an embodiment of the present invention, the number of distributed ray sources and detectors can be flexibly adjusted according to specific application requirements to meet CT imaging requirements in different fields and scenarios.

[0072] It should also be understood that Figure 2The distributed ray source in the figure includes 11 targets, and the number of targets shown in other figures are only exemplary embodiments and should not be understood as limiting the number of targets in the embodiments of the present invention. In other embodiments, the distributed ray source of the CT imaging system may include a smaller number of targets, such as less than 10, or a larger number of targets, such as 20, 50, 100, hundreds or more. In the embodiments of the present invention, the number of targets of the distributed ray source can be flexibly adjusted according to specific application requirements to meet the CT imaging requirements in different fields and scenarios.

[0073] It should be noted that, unless otherwise specifically stated, the expressions "first", "second", "third", etc. recorded in this document are only for the purpose of more conveniently and quickly referring to different components in the description process, such as the distributed ray sources, targets and detectors herein, and should not be understood as any form of limitation on the structures of, for example, the distributed ray sources, targets and detectors. In an embodiment of the present invention, the structures of the first distributed ray source 101, the second distributed ray source 102, the third distributed ray source 103, ... the Mth distributed ray source 10M may be the same, or the structures of some of the distributed ray sources may be the same, and the structures of the other part of the distributed ray sources may be different. For example, the first distributed ray source 101, the second distributed ray source 102, the third distributed ray source 103, ... the Mth distributed ray source 10M may include the same number of targets, or the number of targets included in some of the distributed ray sources may be different from the number of targets included in another part of the distributed ray sources, or the number of targets included in any two distributed ray sources is different. In an embodiment of the present invention, the structures of the first detector 301, the second detector 302, the third detector 303, ... the Nth detector 30N may be the same, or the structures of some of the detectors may be the same and the structures of other detectors may be different.

[0074] It should also be noted that the structure of distributed radiation sources is highly flexible and diverse, and its design and construction depend on many factors, including but not limited to specific application scenarios, imaging requirements, technical requirements, and engineering feasibility. Each distributed radiation source can be independently optimized and adjusted according to actual conditions to achieve the best performance. Whether in the fields of medical diagnosis, security inspection, industrial inspection, or scientific research, the structure of distributed radiation sources can be customized according to different goals and tasks without being constrained by the simple numbering method used here. This numbering method is only for the convenience of distinguishing and discussing each distributed radiation source in the text description, and should not be misunderstood as setting any fixed pattern or limitation for its complex and sophisticated structure.

[0075] Combined with reference Figures 1 to 4C In this article, for the convenience of description, the first direction z, the second direction x, the third direction y, the circumferential direction c and the radial direction r of the imaging channel are described respectively. For example, the first direction z corresponds to the extension direction of the imaging channel 80, or, when the object 70 to be imaged moves, corresponds to its moving direction. The second direction x and the third direction y intersect, and the first direction z is perpendicular to both the second direction x and the third direction y. For example, the second direction x corresponds to the width direction of the CT imaging system, and the third direction y corresponds to the height direction of the CT imaging system. The circumferential direction c and the radial direction r of the imaging channel intersect, and the first direction z is perpendicular to both the circumferential direction c and the radial direction r of the imaging channel. For example, the radial direction r of the imaging channel 80 corresponds to the direction from the center of the imaging channel 80 to the periphery of the imaging channel 80, and the circumferential direction c of the imaging channel 80 corresponds to the direction surrounding the imaging channel 80.

[0076] Reference Figures 2 to 4C , M distributed ray sources 101 ~ 10M are arranged along the circumferential direction c of the imaging channel 80 . Exemplarily, the M distributed ray sources 101 ~ 10M are arranged at intervals along the circumferential direction c of the imaging channel 80 .

[0077] Continue to refer to Figures 2 to 4C , N detectors 301 ~ 30N are arranged along the circumferential direction c of the imaging channel 80. Exemplarily, the N detectors 301 ~ 30N are arranged at intervals along the circumferential direction c of the imaging channel 80.

[0078] In some exemplary embodiments, the M distributed ray sources 101-10M and the N detectors 301-30N are alternately arranged along the circumferential direction c of the imaging channel 80. For example, the M distributed ray sources 101-10M are arranged at equal intervals along the circumferential direction c of the imaging channel 80, and one detector is arranged between two adjacent distributed ray sources. The N detectors 301-30N are arranged at equal intervals along the circumferential direction c of the imaging channel 80, and one distributed ray source is arranged between two adjacent detectors.

[0079] It should be understood that Figure 2 , Figure 3B , FIG. 4A to FIG. 4C They respectively represent the plane schematic diagrams perpendicular to the first direction z, that is, Figure 2 , Figure 3B , FIG. 4A to FIG. 4C The paper plane where is perpendicular to the first direction z. Figure 2 , Figure 3B , FIG. 4A to FIG. 4C As shown, in a plane perpendicular to the first direction z, M distributed ray sources 101-10M and N detectors 301-30N surround and form a closed or approximately closed polygon. Figure 2 and Figure 3B In the figure, three distributed ray sources 101-103 and three detectors 301-303 surround and form a hexagon; Figure 4A In the figure, two distributed ray sources 101-102 and two detectors 301-302 surround and form a quadrilateral; Figure 4B In the figure, five distributed ray sources 101-105 and five detectors 301-305 surround and form a decagon; Figure 4C In the figure, M distributed ray sources 101-10M and N detectors 301-30N surround and form a (M+N)-gon.

[0080] In some exemplary embodiments of the present invention, the CT imaging system 100 includes a plurality of imaging components.

[0081] It should be noted that, in this article, the expression "imaging component" may refer to a component that can perform imaging based on detected rays, which may include a ray source for emitting rays and a detector for detecting rays emitted by the ray source, and it can perform imaging based on the rays detected by the detector.

[0082] For example, an imaging assembly may include at least one distributed ray source and at least one detector. In the same imaging assembly, the distributed ray source and the detector are arranged face to face in the radial direction r of the imaging channel 80. Figure 2 and Figure 3B In the figure, the first distributed ray source 101 and the first detector 301 are arranged face to face in the radial direction r of the imaging channel 80, and the two constitute an imaging component; the second distributed ray source 102 and the second detector 302 are arranged face to face in the radial direction r of the imaging channel 80, and the two constitute an imaging component; the third distributed ray source 103 and the third detector 303 are arranged face to face in the radial direction r of the imaging channel 80, and the two constitute an imaging component.

[0083] In some exemplary embodiments of the present invention, in the same imaging assembly, a plurality of target points of the distributed ray source and at least a portion of the detector are located in the same plane perpendicular to the first direction z.

[0084] In some exemplary embodiments of the present invention, q target points of at least one distributed radiation source are arranged at intervals along a straight line. Figure 3A and Figure 3B, the q target points of the first distributed ray source 101 are arranged at intervals along the first straight line L1. The extension direction of the first straight line L1 may be perpendicular to both the first direction z and the radial direction r. In the same imaging assembly including the first distributed ray source 101 and the first detector 301, the first straight line L1 and at least a portion of the first detector 101 (the portion directly facing the first distributed ray source 101) are located in the same first plane P1 perpendicular to the first direction z.

[0085] That is, in the embodiment of the present invention, the CT imaging system adopts a source-detector coplanar structure. Specifically, multiple distributed ray sources and multiple detectors are located in the same plane perpendicular to the first direction z. By adopting the design of distributed ray sources and source-detector coplanar at the same time, more complete data can be obtained at different angles, thereby reducing signal loss, obtaining more detailed image details, and allowing faster scanning.

[0086] It should be noted that, in this article, unless otherwise specified, the expressions "source and detector are coplanar", "coplanar", "located in the same plane" and other similar expressions not only include that two components (such as a ray source and a detector) are located in the same plane in a geometric sense, but also include that two components (such as a ray source and a detector) are located in the same plane in an engineering sense. For example, the plane in which the two components are located may have a certain thickness, and the thickness of the plane may be determined by the process dimensions of the components. For example, it may be determined by the size of the target point of the ray source along the first direction z. When the detector includes multiple rows of detector units, it may be determined by the size of a single row of detectors along the first direction z.

[0087] In some exemplary embodiments of the present invention, the multiple target points of the M distributed radiation sources included in the CT imaging system are all located in the same plane perpendicular to the first direction z. Figure 3A and Figure 3B The q target points of the first distributed ray source 101, the q target points of the second distributed ray source 102, and the q target points of the third distributed ray source 103 are all located in the same first plane P1 perpendicular to the first direction z.

[0088] That is to say, in the embodiment of the present invention, the overall source-detector arrangement of the CT imaging system adopts a source-detector coplanar structure. By adopting the design of distributed ray sources and overall source-detector coplanarity at the same time, the CT imaging system can be made compact and miniaturized, and more complete data can be obtained at different angles, thereby reducing signal loss, obtaining finer image details, and allowing faster scanning.

[0089] For example, refer to Figure 2The CT imaging system 100 may further include a collimator 104. For example, the collimator 104 may be located in front of the distributed ray source to limit the direction and range of the ray beam emitted by the distributed ray source, ensuring that the ray beam can be accurately projected onto the object to be imaged, thereby reducing the interference of scattered rays and improving the clarity of imaging.

[0090] In the embodiment of the present invention, the controller 50 can adjust the scanning mode of each target in the distributed ray source through several key parameters to achieve the best image quality and imaging efficiency. For example, the controller 50 can control at least one of the following aspects of each target according to the actual imaging requirements: the activation time of each target, the emission range, the beam sequence, the emission intensity, and the beam combination mode of each target.

[0091] In an embodiment of the present invention, M distributed ray sources can be arranged at intervals along the circumferential direction of the imaging channel and distributed at different angles in the imaging area, so as to irradiate the object to be imaged from multiple directions and obtain perspective images at different angles; and N detectors can also be arranged at intervals along the circumferential direction of the imaging channel, respectively opposite to the M distributed ray sources, for receiving ray signals passing through the object to be imaged and converting them into electrical signals to obtain CT projection data.

[0092] For example, Figure 3A As shown in the figure, three distributed ray sources are distributed at different angles in the imaging area and arranged in a polygonal shape. This design can irradiate the object to be imaged from multiple directions, thereby obtaining perspective images at different angles; in contrast to the distributed ray sources, three detectors are arranged around the imaging area to receive ray signals that pass through the object to be imaged. The positional relationship between the detectors and the ray sources ensures that the system can obtain high-quality CT projection data.

[0093] like Figure 3BAs shown, the dotted line marked in the figure represents the longest imaging optical path of the X-ray emitted from the distributed ray source after passing through the object to be imaged to reach the detector on the opposite side. Exemplarily, for the first distributed ray source 101 located at the top, the optical path LP1 represents the optical path of the ray emitted from the first target point located at the far left and incident on the rightmost unit of the first detector 301, and the optical path LP2 represents the optical path of the ray emitted from the qth target point located at the far right and incident on the leftmost unit of the first detector 301. The two optical paths LP1 and LP2 intersect at point Q1 in the plane P1 where the source and the detector are located. The area enclosed by the two optical paths LP1 and LP2 and the detection surface of the first detector 301 is the first imaging area of ​​the imaging assembly including the first distributed ray source 101 and the first detector 301. For the second distributed ray source 102 located on the left, the optical path LP3 represents the optical path of the ray emitted from the first target point located on the uppermost side and incident on the lowermost unit of the second detector 302, and the optical path LP4 represents the optical path of the ray emitted from the qth target point located on the lowermost side and incident on the uppermost unit of the second detector 302. The two optical paths LP3 and LP4 intersect at point Q2 in the plane P1 where the source and detector are located. The area enclosed by the two optical paths LP3 and LP4 and the detection surface of the second detector 302 is the second imaging area of ​​the imaging assembly including the second distributed ray source 102 and the second detector 302. For the third distributed ray source 103 located on the right, the optical path LP5 represents the optical path of the ray emitted from the first target point located at the uppermost side and incident on the lowermost unit of the third detector 303, and the optical path LP6 represents the optical path of the ray emitted from the qth target point located at the lowermost side and incident on the uppermost unit of the third detector 303. The two optical paths LP5 and LP6 intersect at point Q3 in the plane P1 where the source and detector are located. The area enclosed by the two optical paths LP5 and LP6 and the detection surface of the third detector 303 is the third imaging area of ​​the imaging assembly including the third distributed ray source 103 and the third detector 303. The overlapping area of ​​the first imaging area, the second imaging area and the third imaging area constitutes a polygonal area. For example, in Figure 3B In the example, an approximately triangular area is formed, and the maximum inscribed circle of the polygonal area constitutes the effective imaging area S.

[0094] The applicant has found through research that although the closed-loop structure in which the target of the distributed ray source is coplanar with the detector and distributed around the object to be imaged can bring convenience in design and operation, due to the limitation of the source-detector spacing and the source-detector length ratio, the ray angle coverage is limited, which may lead to the problem of limited angle scanning. In the image reconstruction process, it is necessary to consider the related issues of limited angle reconstruction, and the area of ​​the object to be imaged is limited. In addition, since the effective imaging area covered by the scanning path is limited, when some parts of the object to be imaged exceed the effective imaging area S, the projection data of this part may not be obtained, resulting in missing or distorted information in some areas of the reconstructed image, that is, data truncation. In practical applications, especially when detecting complex or high-density objects, the problem of data truncation will affect the comprehensiveness and accuracy of detection and imaging.

[0095] The applicant has also discovered through research that, as another scanning imaging scheme for distributed light sources, the relevant technology has also proposed a scanning system in which the target point and the detector of the ray source are distributed in different planes, that is, the target point and the detector are distributed in two or more planes. This scanning method causes the rays to scan the object obliquely, resulting in data truncation problems.

[0096] Based on this, an embodiment of the present invention further proposes a CT imaging system, in which two types of detectors are provided, one type is the detector as described above, which is respectively provided face to face with each distributed ray source; the other type is provided on the same side as the distributed ray source. In this article, for the convenience of description, these two types of detectors are respectively described as the first sub-detector and the second sub-detector.

[0097] That is to say, in some embodiments of the present invention, by placing multiple target points of a distributed ray source and a first sub-detector in the same plane perpendicular to the imaging channel and arranging a second sub-detector on the same side of the ray source, the effective imaging area can be expanded and the imaging quality of the edges and corners of the object can be improved, thereby achieving more complete and effective ray projection and reception and improving imaging efficiency.

[0098] For example, some embodiments of the present invention provide a CT imaging system, comprising: an imaging channel, at least a portion of which extends along a first direction, the imaging channel being used to place an object to be imaged during an imaging process; M distributed ray sources, the M distributed ray sources being arranged at intervals along a circumferential direction of the imaging channel, at least one distributed ray source comprising q target points, the q target points being configured to be activated in a predetermined order to emit rays, M and q being positive integers greater than or equal to 2; and N detectors, the N detectors being arranged at intervals along a circumferential direction of the imaging channel, the N detectors being used to detect rays emitted from the M distributed ray sources and passing through the object to be imaged, N is a positive integer greater than M, wherein the detector includes a first sub-detector and a second sub-detector, the CT imaging system includes a plurality of imaging components, the imaging components include at least one distributed ray source and at least one first sub-detector, in the same imaging component, the distributed ray source and the first sub-detector are arranged face to face in a radial direction of an imaging channel, and, in the same imaging component, a plurality of target points of the distributed ray source and at least a portion of the first sub-detector are located in a same plane perpendicular to a first direction, and the radial direction is perpendicular to the first direction; and in the first direction, at least one side of at least one distributed ray source is provided with at least one second sub-detector.

[0099] In this embodiment, by arranging the second sub-detector on the same side of the ray source, the X-rays can be simultaneously received by multiple sub-detectors including the first sub-detector and the second sub-detector after passing through the object to be imaged, thereby enhancing the coverage of different angles, reducing data truncation or loss, and improving the detection accuracy.

[0100] Figure 5 A stereoscopic schematic diagram of a CT imaging system according to some exemplary embodiments of the present invention is shown, wherein the detector includes two types of detectors. Figure 6 According to some exemplary embodiments of the present invention, Figure 5 Schematic diagram of the imaging optical path of the CT imaging system. Fig. 8A is a plan view schematically illustrating an arrangement of distributed ray sources and detectors included in a CT imaging system according to some exemplary embodiments of the present invention, wherein two distributed ray sources and two detectors are schematically illustrated; Figure 8B is a plan view schematically illustrating an arrangement of distributed ray sources and detectors included in a CT imaging system according to some exemplary embodiments of the present invention, wherein five distributed ray sources and five detectors are schematically illustrated; Figure 8C It is a plan view schematically illustrating the arrangement of distributed ray sources and detectors included in a CT imaging system according to some exemplary embodiments of the present invention, wherein a plurality of distributed ray sources and a plurality of detectors are schematically illustrated.

[0101] It should be noted that, in the absence of conflict, the contents and features described above can be combined with the various embodiments described below. In order to save space, the description will not be repeated in the various embodiments below. For example, in the embodiments described below, a CT imaging system with a three-segment scanning structure is taken as an example to describe the embodiments of the present invention in detail. It should be understood that the following CT imaging system with a three-segment scanning structure is only an exemplary CT imaging system structure for the convenience of explanation. Those skilled in the art should understand that the number and position of ray sources and detectors can be adjusted according to specific needs to adapt to objects to be imaged of different sizes and shapes. For example, the situations of 3 distributed ray sources, 2 distributed ray sources, 5 distributed ray sources, and M distributed ray sources described above can be combined in the various embodiments described below.

[0102] Combined with reference Figure 1 , Figure 5 , Figure 6 and FIG. 8A to FIG. 8C In some exemplary embodiments, the ray source of the CT imaging system 200 may include a plurality of distributed ray sources, for example, M distributed ray sources, where M is a positive integer greater than or equal to 2. In this document, for the convenience of description, the M distributed ray sources are numbered as a first distributed ray source 210, a second distributed ray source 220, a third distributed ray source 230, ..., and an Mth distributed ray source 2M0.

[0103] In some exemplary embodiments, the detection and acquisition device 30 of the CT imaging system 200 may include a plurality of detectors, for example, N detectors 202, where N is a positive integer greater than or equal to 2. For example, N is a positive integer greater than or equal to M. In this embodiment, two types of detectors may be provided, that is, the detector 202 may include a first sub-detector 2021 and a second sub-detector 2022. For example, the CT imaging system 200 may include N1 first sub-detectors 2021 and N2 second sub-detectors 2022. N is equal to the sum of N1 and N2, where N1 is a positive integer greater than or equal to 2, and N2 is a positive integer greater than or equal to 2.

[0104] Exemplarily, N1 may be equal to M, that is, the number of first sub-detectors is equal to the number of distributed ray sources.

[0105] In this article, for the convenience of description, the N1 first sub-detectors are numbered as the first first sub-detector 20211, the second first sub-detector 20212, the third first sub-detector 20213, ... the N1th first sub-detector 2021N1; the N2 second sub-detectors are numbered as the first second sub-detector 20221, the second second sub-detector 20222, the third second sub-detector 20223, ... the N2th second sub-detector 2022N2.

[0106] That is, in this embodiment, the CT imaging system 200 may include: an imaging channel 80, at least a portion of which extends along a first direction z, and the imaging channel 80 is used to place an object to be imaged 70 during imaging; M distributed ray sources, which are arranged at intervals along a circumferential direction c of the imaging channel 80, and at least one distributed ray source includes q target points 2011, which are configured to be activated in a predetermined order to emit rays, and M and q are both positive integers greater than or equal to 2; and N detectors 202, which are arranged at intervals along a circumferential direction c of the imaging channel 80, and are used to detect rays emitted from the M distributed ray sources and passing through the object to be imaged 70, and N is a positive integer greater than M. The detector 202 includes a first sub-detector 2021 and a second sub-detector 2022. The CT imaging system 200 includes multiple imaging components, each of which includes at least one distributed ray source and at least one first sub-detector 2021. In the same imaging component, the distributed ray source and the first sub-detector 2021 are arranged face to face in the radial direction r of the imaging channel 80, and in the same imaging component, multiple target points 2011 of the distributed ray source and at least a portion of the first sub-detector 2021 are located in the same plane perpendicular to the first direction z, and the radial direction r is perpendicular to the first direction z; and in the first direction z, at least one second sub-detector 2022 is arranged on at least one side of at least one distributed ray source.

[0107] In this embodiment, the distributed ray source and the first sub-detector 2021 are not only arranged at intervals in the circumferential direction c, but at least a portion of the first sub-detectors and at least a portion of the multiple targets are in a plane perpendicular to the imaging channel 80. In addition, by introducing the second sub-detector 2022 to work in conjunction with the first detector 2021, rays from the distributed ray source can be received from different angles or positions, thereby expanding the detection range. This three-dimensional spatial arrangement breaks through the traditional design of circumferential arrangement, allowing the CT imaging system 200 to detect from multiple angles at the same time, improving the accuracy and breadth of detection, thereby effectively solving the limited angle scanning problem and data truncation problem.

[0108] Reference Figure 5 , Figure 6 and FIG. 8A to FIG. 8C , M distributed ray sources 210 ~ 2M0 are arranged along the circumferential direction c of the imaging channel 80. Exemplarily, the M distributed ray sources 210 ~ 2M0 are arranged at intervals along the circumferential direction c of the imaging channel 80.

[0109] Continue to refer to Figure 5 , Figure 6 and FIG. 8A to FIG. 8C , N1 first sub-detectors are arranged along the circumferential direction c of the imaging channel 80 . Exemplarily, the N1 first sub-detectors are arranged at intervals along the circumferential direction c of the imaging channel 80 .

[0110] In some exemplary embodiments, the M distributed ray sources 210-2M0 and the N1 first sub-detectors are alternately arranged along the circumferential direction c of the imaging channel 80. For example, the M distributed ray sources 210-2M0 are arranged at equal intervals along the circumferential direction c of the imaging channel 80, and one first sub-detector is disposed between two adjacent distributed ray sources. The N1 first sub-detectors are arranged at equal intervals along the circumferential direction c of the imaging channel 80, and one distributed ray source is disposed between two adjacent first sub-detectors.

[0111] It should be understood that Figure 6 and FIG. 8A to FIG. 8C They respectively represent the plane schematic diagrams perpendicular to the first direction z, that is, Figure 6 and FIG. 8A to FIG. 8C The paper plane where is perpendicular to the first direction z. Figure 6 and FIG. 8A to FIG. 8C As shown, in a plane perpendicular to the first direction z, the M distributed ray sources 210-2M0 and the N1 first sub-detectors surround and form a closed or approximately closed polygon. Figure 6 In the figure, three distributed ray sources 210-230 and three first sub-detectors 20211-20213 surround and form a hexagon; Fig. 8A In the figure, two distributed ray sources 210-220 and two first sub-detectors 20211-20212 surround and form a quadrilateral; Figure 8B In the figure, five distributed ray sources 210-250 and five first sub-detectors 20211-20215 surround and form a decagon; Figure 8C In the figure, M distributed ray sources 210-2M0 and N1 first sub-detectors 20211-2021N1 surround and form a (M+N1)-gon.

[0112] The arrangement of the ray source and detector determines the spatial resolution and field of view of CT imaging. This closed or nearly closed polygonal geometric layout optimizes the viewing angle of the imaging system, allowing each detector to receive signals from different angles, effectively increasing the amount of projection data to cover the imaging area to the greatest extent possible.

[0113] Reference Figure 5 The distributed ray source may include a first side 211 and a second side 212 that are arranged opposite to each other in a first direction z. For example, the first side 211 is downstream of the second side 212 .

[0114] In an embodiment of the present invention, for at least one distributed ray source, in the first direction z, one or more second sub-detectors may be arranged on at least one of the first side 211 and the second side 212 of the distributed ray source.

[0115] Fig.8D A schematic diagram showing an arrangement of distributed ray sources and second sub-detectors according to some embodiments of the present invention is shown. Fig. 8E Schematic diagrams showing arrangements of distributed ray sources and second sub-detectors according to other embodiments of the present invention.

[0116] Reference Figure 5 In the first direction z, second sub-detectors 2022 are respectively arranged on the first side 211 and the second side 212 of the distributed ray source.

[0117] Reference Fig.8D In the first direction z, a second sub-detector 2022 is arranged on only the first side 211 of the distributed ray source.

[0118] Reference Fig. 8E In the first direction z, a second sub-detector 2022 is respectively arranged on only the second side 212 of the distributed ray source.

[0119] In an embodiment of the present invention, in the first direction z, at least one second sub-detector 2022 is disposed on the first side 211 of the M' distributed ray sources; or, in the first direction z, at least one second sub-detector 2022 is disposed on the second side 212 of the M' distributed ray sources; or, in the first direction z, at least one second sub-detector 2022 is disposed on the first side 211 and the second side 212 of the M' distributed ray sources, respectively, wherein M' is greater than or equal to 1 and less than or equal to M.

[0120] In this embodiment, a second sub-detector 2022 is provided, and the position of the second sub-detector is flexibly arranged to work better with the first detector 2021, and rays from a distributed ray source can be received from different angles or positions, thereby expanding the detection range. This three-dimensional spatial arrangement breaks through the traditional design of circumferential arrangement, allowing the imaging system to detect from multiple angles simultaneously, improving the accuracy and breadth of detection, thereby effectively solving the limited angle scanning problem and data truncation problem.

[0121] For example, N2=2M, that is, the number of second sub-detectors N2 can be equal to twice the number of distributed ray sources, that is, a second sub-detector is set on both sides of each distributed ray source. Through such a setting, the detection range can be expanded for each distributed ray source, and the accuracy and breadth of detection can be better improved, so that the limited angle scanning problem and data truncation problem can be more effectively solved.

[0122] In some exemplary embodiments of the invention, the CT imaging system 200 includes a plurality of imaging components.

[0123] For example, in this embodiment, an imaging assembly may include at least one distributed ray source, at least one first sub-detector, and at least a portion of at least one second sub-detector. In the same imaging assembly, the distributed ray source and the first sub-detector are arranged face to face in the radial direction r of the imaging channel 80, and the distributed ray source and at least a portion of the second sub-detector are arranged face to face in the radial direction r of the imaging channel 80. For example, in Figure 5 and Figure 6 In the figure, the first distributed ray source 210 and the first first sub-detector 20211 are arranged face to face in the radial direction r of the imaging channel 80, the first distributed ray source 210 and a part of the third second sub-detector and a part of the fourth second sub-detector are arranged face to face in the radial direction r of the imaging channel 80, the first distributed ray source 210 and a part of the fifth second sub-detector and a part of the sixth second sub-detector are arranged face to face in the radial direction r of the imaging channel 80, and these face-to-face arranged components constitute an imaging assembly; by analogy, the second distributed ray source 220 and the detector part arranged face to face therewith constitute an imaging assembly, and the third distributed ray source 230 and the detector part arranged face to face therewith constitute an imaging assembly.

[0124] In some exemplary embodiments of the present invention, in the same imaging assembly, a plurality of target points of the distributed ray source and at least a portion of the first sub-detector are located in the same plane perpendicular to the first direction z.

[0125] In some exemplary embodiments of the present invention, q target points of at least one distributed radiation source are arranged at intervals along a straight line. Figure 5 and Figure 6 , the q target points of the first distributed ray source 210 are arranged at intervals along the first straight line L1. The extension direction of the first straight line L1 may be perpendicular to both the first direction z and the radial direction r. In the same imaging assembly including the first distributed ray source 210 and the first first sub-detector 20211, the first straight line L1 and at least a portion of the first first sub-detector 20211 (the portion directly facing the first distributed ray source 210) are located in the same first plane P1 perpendicular to the first direction z.

[0126] That is, in the embodiment of the present invention, the CT imaging system adopts a source-detector coplanar structure. Specifically, a plurality of distributed ray sources and a portion of a plurality of first sub-detectors are located in the same plane perpendicular to the first direction z. By adopting the design of distributed ray sources and source-detector coplanar at the same time, more complete data can be obtained at different angles, thereby reducing signal loss, obtaining finer image details, and allowing faster scanning.

[0127] In some exemplary embodiments of the present invention, the multiple target points of the M distributed radiation sources included in the CT imaging system are all located in the same plane perpendicular to the first direction z. Figure 5 and Figure 6 The q target points of the first distributed ray source 210, the q target points of the second distributed ray source 220, and the q target points of the third distributed ray source 230 are all located in the same first plane P1 perpendicular to the first direction z.

[0128] That is to say, in the embodiment of the present invention, the overall source-detector arrangement of the CT imaging system adopts a source-detector coplanar structure. By adopting the design of distributed ray sources and overall source-detector coplanarity at the same time, the CT imaging system can be made compact and miniaturized, and more complete data can be obtained at different angles, thereby reducing signal loss, obtaining finer image details, and allowing faster scanning.

[0129] In the embodiment of the present invention, the controller 50 can adjust the scanning mode of each target in the distributed ray source through several key parameters to achieve the best image quality and imaging efficiency. For example, the controller 50 can control at least one of the following aspects of each target according to the actual imaging requirements: the activation time of each target, the emission range, the beam sequence, the emission intensity, and the beam combination mode of each target.

[0130] In an embodiment of the present invention, M distributed ray sources can be arranged at intervals along the circumferential direction of the imaging channel, distributed at different angles of the imaging area, and irradiate the imaging object from multiple directions to obtain perspective images at different angles; and N1 first sub-detectors can also be arranged at intervals along the circumferential direction of the imaging channel, respectively opposite to the M distributed ray sources.

[0131] For example, Figure 5 As shown in the figure, three distributed ray sources are distributed at different angles in the imaging area and arranged in a polygonal shape. Such a design can irradiate the object to be imaged from multiple directions, thereby obtaining perspective images at different angles; in contrast to the distributed ray sources, three first sub-detectors are arranged around the imaging area to receive ray signals that pass through the object to be imaged. The positional relationship between the detector and the ray source ensures that the system can obtain high-quality CT projection data.

[0132] like Figure 6 As shown in the figure, the dotted line marked in the figure represents the longest imaging optical path of the X-ray emitted from the distributed ray source after passing through the object to be imaged to reach the detector on the opposite side. Exemplarily, for the first distributed ray source 210 located at the top, the optical path LP10 represents the optical path of the ray emitted from the first target point located at the far left and incident on the detection unit of a second sub-detector on the opposite side. It should be noted that since the second sub-detector is arranged on the opposite side of the first distributed ray source 210, the optical path LP10 can irradiate the object to be imaged at a larger angle.

[0133] Exemplarily, the optical path LP20 represents the optical path of the ray emitted from the qth target point located on the far right and incident on the detection unit of another second sub-detector opposite. It should still be noted that, since another second sub-detector is arranged opposite the first distributed ray source 210, the optical path LP20 can illuminate the object to be imaged at a larger angle.

[0134] The two optical paths LP10 and LP20 intersect at a point Q10 in the plane P1 where the source detector is located. The area enclosed by the two optical paths LP10 and LP20 and the detection surface of the detector is the first imaging area.

[0135] For the second distributed ray source 220 located on one side, the optical path LP30 represents the optical path of the ray emitted from the first target point located on the uppermost side and incident on the detection unit of a second sub-detector on the opposite side. The optical path LP40 represents the optical path of the ray emitted from the qth target point located on the lowermost side and incident on the detection unit of another second sub-detector on the opposite side. The two optical paths LP30 and LP40 intersect at point Q20 in the plane P1 where the source and detector are located, and the area enclosed by the two optical paths LP30 and LP40 and the detection surface of the detector includes the second imaging area.

[0136] For the third distributed ray source 230 located on the other side, the optical path LP50 represents the optical path of the ray emitted from the first target point located on the uppermost side and incident on the detection unit of a second sub-detector on the opposite side. The optical path LP60 represents the optical path of the ray emitted from the qth target point located on the lowermost side and incident on the detection unit of another second sub-detector on the opposite side. The two optical paths LP50 and LP60 intersect at point Q30 in the plane P1 where the source and detector are located, and the area enclosed by the two optical paths LP50 and LP60 and the detection surface of the detector is the third imaging area.

[0137] The overlapping area of ​​the first imaging area, the second imaging area and the third imaging area constitutes a polygonal area. Figure 6 In the example of FIG. 1 , a triangular area is formed, and the maximum inscribed circle of the polygonal area constitutes the effective imaging area S10.

[0138] Figure 7 Schematic diagram of imaging optical paths of CT imaging systems according to other exemplary embodiments of the present invention. It should be noted that: Figure 7 The imaging optical path diagram shown can be considered as Figure 6 A comparative example of the imaging optical path schematic diagram shown, that is, Figure 7 The CT imaging system is Figure 6 The CT imaging system targeted (i.e. Figure 5 The CT imaging system shown in the figure only differs in that: Figure 7 The second sub-detector mentioned above is not provided in the targeted CT imaging system.

[0139] like Figure 7 As shown in the figure, the dotted line marked in the figure represents the longest imaging light path of the X-ray emitted from the distributed ray source after passing through the object to be imaged and reaching the detector on the opposite side. Figure 7 In order to make the attached figure concise, the optical paths of the distributed ray sources are simplified. Since the optical paths of the rays emitted by some distributed ray sources overlap, Figure 7 Each light path schematically shown by the dashed line can represent some overlapping ray paths, that is, Figure 7 Can be seen as Figure 3B A simplified version of the optical path.

[0140] For example, Figure 7As shown, for the first distributed ray source 101 located at the top, the optical path LP01 represents the optical path of the ray emitted from the first target point located at the far left and incident on the rightmost unit of the first detector 301, and the optical path LP02 represents the optical path of the ray emitted from the qth target point located at the far right and incident on the leftmost unit of the first detector 301. The two optical paths LP01 and LP02 intersect at point Q01 in the plane P1 where the source and detector are located. The area enclosed by the two optical paths LP01 and LP02 and the detection surface of the first detector 301 is the first imaging area of ​​the imaging component including the first distributed ray source 101 and the first detector 301. For the second distributed ray source 102 located on one side, the optical path LP03 represents the optical path of the ray emitted from the first target point located on the uppermost side and incident on the lowermost unit of the second detector 302, and the optical path LP04 represents the optical path of the ray emitted from the qth target point located on the lowermost side and incident on the uppermost unit of the second detector 302. The two optical paths LP03 and LP04 intersect at point Q02 in the plane P1 where the source and detector are located. The area enclosed by the two optical paths LP03 and LP04 and the detection surface of the second detector 302 is the second imaging area of ​​the imaging assembly including the second distributed ray source 102 and the second detector 302. For the third distributed ray source 103 located on the other side, the optical path LP05 represents the optical path of the ray emitted from the first target point located at the uppermost side and incident on the lowermost unit of the third detector 303, and the optical path LP06 represents the optical path of the ray emitted from the qth target point located at the lowermost side and incident on the uppermost unit of the third detector 303. The two optical paths LP05 and LP06 intersect at point Q03 in the plane P1 where the source and detector are located. The area enclosed by the two optical paths LP05 and LP06 and the detection surface of the third detector 303 is the third imaging area of ​​the imaging assembly including the third distributed ray source 103 and the third detector 303. The overlapping area of ​​the first imaging area, the second imaging area and the third imaging area constitutes a polygonal area. For example, in Figure 7 In the example of , a triangular area is formed, and the maximum inscribed circle of the polygonal area constitutes the effective imaging area S1.

[0141] exist Figure 7 In the case of , since the second sub-detector is not arranged, only area S1 of the object to be imaged can be completely covered by the detector, and there is a data truncation problem outside the S1 area (only part of the rays can be covered); while Figure 6In the system shown, a second sub-detector is provided on at least one side of the distributed ray source, so that the angle range of rays that can be received by the detector from each ray source is expanded. That is to say, by providing a second sub-detector, the effective imaging area can be expanded from S1 to S10 while keeping factors such as the position and size of other components unchanged, thereby effectively reducing or even avoiding the problem of data truncation.

[0142] It should be noted that for a system with source and detector arranged in the circumferential direction, the rays intersect in the central area to form a polygonal effective imaging area, and this intersection is the main imaging area. For the convenience of explanation and comparison, the tangent circle of the polygon is used as the effective imaging area.

[0143] In the embodiments of the present invention, the detector can be a single-row detector, a multi-row detector or a surface detector, and a suitable detector type can be selected in different application scenarios to optimize the imaging efficiency and effect. Among them, the single-row detector includes a plurality of detection units, and the plurality of detection units are arranged along a straight line; the multi-row detector includes a plurality of rows of detector units, and each row of detector units includes a plurality of detector units, forming a matrix or grid structure; the surface detector covers a larger plane area, and the detection units are densely arranged to form a continuous detection surface.

[0144] In the embodiment of the present invention, a flexible detector layout design is also provided, which is applicable to the first sub-detector 2021 and the second sub-detector 2022. In other words, different arrangements can be designed to meet different imaging requirements.

[0145] Fig. 9A A schematic diagram showing a layout design of densely arranged detectors according to some embodiments of the present invention; Fig. 9B A schematic diagram showing a layout design of sparsely arranged detectors according to some other embodiments of the present invention; Fig. 9C A schematic diagram showing a layout design of a mixed arrangement of detectors according to some further embodiments of the present invention.

[0146] Combined with reference Figure 9A-9C For example, the first sub-detector 2021 may include multiple rows of detector units DU, and the multiple rows of detector units are densely arranged along the first direction z; or, the first sub-detector 2021 may include multiple rows of detector units, and the multiple rows of detector units are sparsely arranged along the first direction z; or, the first sub-detector 2021 may include multiple rows of detector units, in the middle area of ​​the first sub-detector 2021, a part of the multiple rows of detector units are densely arranged in the first direction z, and in the two side areas of the first sub-detector 2021, another part of the multiple rows of detector units are sparsely arranged in the first direction z.

[0147] Similarly, the second sub-detector 2022 may include multiple rows of detector units, which are densely arranged along the first direction z; or, the second sub-detector 2022 may include multiple rows of detector units, which are sparsely arranged along the first direction z; or, the second sub-detector 2022 may include multiple rows of detector units, in the middle area of ​​the second sub-detector 2022, a part of the multiple rows of detector units are densely arranged in the first direction z, and in the two side areas of the second sub-detector 2022, another part of the multiple rows of detector units are sparsely arranged in the first direction z.

[0148] According to an embodiment of the present invention, in the case of dense arrangement, the detector can collect more radiation information, thereby enhancing the details of the image, which is particularly useful when imaging a small area or requiring high-precision observation. This layout is suitable for high-resolution imaging, such as the detection of fine structures or medical applications that require precise measurement; sparse arrangement can reduce cost and complexity, or provide sufficient image quality when high-resolution imaging is not required, and is suitable for large-scale imaging or occasions with high requirements for imaging speed; for applications that need to consider cost, imaging range and detailed imaging of the central area at the same time, such as certain types of medical diagnosis or industrial inspection, the advantages of the first two configurations can be combined, using dense arrangement in the middle area of ​​the detector to ensure high resolution of the imaging center area, while sparse arrangement on both sides can expand the imaging range while controlling cost and complexity of processing data.

[0149] In an embodiment of the present invention, the above-mentioned multiple rows of detector units may further include a middle row of detector units, which are located in the middle of the multiple rows of detector units in the first direction z. In the same imaging assembly, the multiple targets of the distributed ray source and the middle row of detector units of the first sub-detector are located in the same plane perpendicular to the first direction. That is, the multiple targets of the distributed ray source and the middle row of detector units of the first sub-detector may be located in the same plane, thereby ensuring precise alignment between the ray source and the detector, and improving imaging quality and consistency.

[0150] According to an embodiment of the present invention, the CT imaging system may further include a plurality of source-detector assemblies, wherein the source-detector assemblies include a distributed ray source and at least one second sub-detector 2022. The plurality of source-detector assemblies may be flexibly combined and arranged to meet different imaging requirements. For example, the CT imaging system may adapt to imaging requirements of different sizes, shapes or resolutions by adding or reducing source-detector assemblies.

[0151] For example, an odd number of source-detection components may be provided, which may be as follows: Figure 5The three shown can also be five, etc. Using an odd number of source-detector assemblies can create a balance between symmetry and geometric center. This symmetry helps optimize the distribution of rays so that the CT imaging system can obtain more uniform coverage at different angles. At the same time, an odd number of sources can evenly distribute rays and provide more consistent exposure in different directions of the object to be imaged, thereby reducing imaging errors caused by angle deviations.

[0152] In the embodiment of the present invention, the orthographic projections of the distributed ray source and at least one second sub-detector 2022 of the same source-detector assembly along the first direction z may at least partially overlap. That is, in the CT imaging system according to the embodiment of the present invention, the arrangement of the distributed ray source and the second sub-detector relative to the object to be imaged should ensure that they have a good geometric alignment relationship during the imaging process to achieve a good detection effect.

[0153] Furthermore, in the same source detection component, if Figure 5 As shown, the dimension d11 of the distributed ray source along the extension direction of the first straight line L1 and the dimension d12 of the second sub-detector 2022 along the extension direction of the first straight line L1 can be substantially equal (the dimensions of each distributed ray source are the same). This design can ensure that the rays emitted by the ray source can be captured by the effective detector along the entire length of the imaging channel.

[0154] Fig. 10A A schematic diagram showing the ray angle coverage in a CT imaging system according to some embodiments of the present invention is shown; Fig. 10B FIG. 1 is a schematic diagram showing the ray angle coverage range in a CT imaging system according to some other embodiments of the present invention. It should be noted that Fig. 10A and Fig. 10B In the CT imaging systems shown in the figure, no second sub-detector is provided.

[0155] Take the arrangement of three distributed ray sources as an example. Fig. 10A As shown in the figure, the line connecting the center point of the polygon and the edge of the distributed ray source represents the ray angle coverage. Fig. 10A Each ray source shown covers an angle of 30°, providing a total scan coverage of 90°; Fig. 10B As shown, Fig. 10B Each ray source covers an angle of 54°, providing a total scanning coverage of 162°.

[0156] Combined with reference Fig. 10A and Fig. 10B, by changing the size of the ray source, or changing the size ratio of the ray source to the detector, the ray coverage angle range of each distributed ray source can be changed, thereby changing the scanning coverage range of the CT imaging system. For example, by increasing the size of the distributed ray source (for example, increasing the size of a single distributed ray source from Fig. 10A The size shown increases to Fig. 10B By increasing the size of the distributed ray source and the size of the detector, or increasing the ratio of the size of the distributed ray source to the size of the detector, the ray coverage angle range of a single distributed ray source can be increased, for example, from 30° to 54°. Correspondingly, the scanning coverage range of the CT imaging system is increased from 90° to 162°.

[0157] Fig.11A A schematic diagram showing an effective imaging area in a CT imaging system according to some embodiments of the present invention; Fig. 11B FIG. 1 is a schematic diagram showing an effective imaging area in a CT imaging system according to some other embodiments of the present invention. It should be noted that Fig.11A and Fig. 11B In the CT imaging systems shown in the figure, no second sub-detector is provided.

[0158] Combined with reference Fig.11A and Fig. 11B , by changing the size of the ray source, or changing the size ratio of the ray source to the detector, the imaging area of ​​each distributed ray source can be changed, thereby changing the effective imaging area of ​​the CT imaging system. For example, by reducing the size of the distributed ray source (for example, a single distributed ray source from Fig.11A The dimensions shown are reduced to Fig. 11B By reducing the size of the distributed ray source and the size of the detector, or by reducing the ratio of the size of the distributed ray source to the size of the detector, the imaging area of ​​the single distributed ray source can be increased. Accordingly, the effective imaging area of ​​the CT imaging system is increased from Sa to Sb.

[0159] In other words, combined with reference FIG. 10A to FIG. 11B When the relative position of the source and the detector and the distance between the source and the detector remain unchanged, reducing the size of the distributed ray source or reducing the ratio of the size of the distributed ray source to the size of the detector can increase the effective imaging area of ​​the CT imaging system, but the scanning coverage of the CT imaging system will be reduced; increasing the size of the distributed ray source or increasing the ratio of the size of the distributed ray source to the size of the detector can increase the scanning coverage of the CT imaging system, but the effective imaging area of ​​the CT imaging system will be reduced.

[0160] In an embodiment of the present invention, by arranging a second sub-detector located at the radiation source side, the increase of the effective imaging area and the increase of the scanning coverage can be achieved simultaneously, that is, the effective imaging area and the scanning coverage can be taken into account, thereby effectively improving the imaging quality.

[0161] Return to reference Figure 5 , Figure 6 and FIG. 8A to FIG. 8E In an embodiment of the present invention, by arranging a second sub-detector located on the side of the ray source, the ray angle coverage range of M distributed ray sources can reach 90°-120°; or the ray angle coverage range of M distributed ray sources can reach 120°-150°; or the ray angle coverage range of M distributed ray sources can reach 140°-160°.

[0162] In the embodiment of the present invention, in the same imaging assembly, the distributed ray source has a first dimension a1 along the extension direction of the first straight line L1, the first sub-detector 2021 has a second dimension a2 along the extension direction parallel to the first straight line L1, and the first dimension a1 is smaller than the second dimension a2. In other words, the effective coverage of the detector is greater than the length of the target line array, which helps the ray beam emitted by each target to be completely received by the detector, thereby increasing the effective imaging area.

[0163] By using different processing methods for moving and stationary objects, the embodiments of the present invention also provide a way to optimize the size of the detector to ensure that complete image data is obtained under various imaging conditions. For moving objects, the detector needs to consider the moving distance of the object and the ray magnification ratio to ensure that all possible motion ranges are covered; for stationary objects, the detector needs to ensure that the area of ​​interest is covered.

[0164] Specifically, for a moving object, the minimum size of the detector can be calculated based on the moving speed of the imaging object and the ray geometry. The size of the first sub-detector 2021 in the first direction z satisfies the following relationship:

[0165] LD=d*p (1)

[0166] Wherein, LD is the size of the first sub-detector in the first direction, d is the moving distance of the object to be imaged in the first direction during one exposure cycle, and p is the ray magnification ratio. The ray magnification ratio is defined as the ratio between the image size on the detector and the actual size of the object, which describes the degree to which the image is magnified due to the different distances between the object and the detector during the imaging process.

[0167] For stationary objects, the size of the first sub-detector 2021 in the first direction z can be greater than or equal to the size of the region of interest of the object to be imaged in the first direction z to ensure that the detector can completely cover the region to be imaged, thereby obtaining complete projection data and avoiding loss of image information.

[0168] In an embodiment of the present invention, Figure 6 and FIG. 8A to FIG. 8C As shown, in a plane perpendicular to the first direction z, M distributed ray sources 210~2M0 and N1 first sub-detectors surround and form a closed or approximately closed polygon. The effective imaging area S1 of the CT imaging system 200 can be located in the middle area of ​​the above-mentioned polygon. It should be noted that the expression "middle area" here refers to the area where the geometric center of the polygon is located and / or the area formed by radially extending a predetermined distance outward from the area where the geometric center is located. Through such a setting, the center of the imaging area coincides or substantially coincides with the geometric center of the polygon, so that the rays can evenly cover the area of ​​interest of the object to be imaged, thereby avoiding the loss of edge data.

[0169] In an embodiment of the present invention, the transmission mechanism 40 is located in the middle area of ​​the above-mentioned polygon. This layout supports the coordinated work between the effective imaging area of ​​the CT imaging system and the transmission mechanism. The transmission mechanism can move the object to be imaged to the middle area of ​​the polygon, so that the object to be imaged can always be in an ideal imaging position during the imaging process, further improving the accuracy and consistency of imaging. Furthermore, the transmission mechanism can be controlled so that the object to be imaged moves stably and smoothly during the imaging process, reducing or even avoiding problems such as image blur or deformation caused by position offset or irregular movement.

[0170] Fig.12 is a stereoscopic schematic diagram of a CT imaging system according to some exemplary embodiments of the present invention, wherein a target point of a distributed ray source is arranged tilted.

[0171] like Fig.12 As shown, the CT imaging system 300 may include: an imaging channel, at least a portion of which extends along a first direction z, and the imaging channel is used to place an object to be imaged during the imaging process; M distributed ray sources 310, which are arranged at intervals along the circumferential direction of the imaging channel, and at least one distributed ray source 310 includes q target points 3011, and the q target points 3011 are configured to be activated in a predetermined order to emit rays, and M and q are both positive integers greater than or equal to 2; and N detectors 402, which are arranged at intervals along the circumferential direction of the imaging channel, and the N detectors 402 are used to detect rays emitted from the M distributed ray sources 310 and passing through the object to be imaged, and N is a positive integer greater than or equal to M.

[0172] Fig.13A is a schematic diagram of a distributed ray source of a CT imaging system according to some exemplary embodiments of the present invention.

[0173] In some exemplary embodiments, the detector 402 includes a first sub-detector 4021, or the detector 402 only includes the first sub-detector 4021. That is, in this embodiment, Fig.13A As shown, the second sub-detector is not disposed on the upper side or the lower side of the distributed ray source 310 .

[0174] In this embodiment, the CT imaging system 300 includes multiple imaging components, the imaging components include at least one distributed ray source 310 and at least one first sub-detector 4021, in the same imaging component, the distributed ray source 310 and the first sub-detector 4021 are arranged face to face in the radial direction r of the imaging channel, and, in the same imaging component, at least one target point 3011 of the distributed ray source and at least a portion of the first sub-detector 4021 are located in the same plane perpendicular to the first direction z, and the radial direction is perpendicular to the first direction z; and the q target points included in at least one of the M distributed ray sources are arranged obliquely relative to the first direction z.

[0175] The applicant has found through research that the movement of an object during data acquisition may lead to inconsistency between consecutive image frames, which may cause motion artifacts. According to an embodiment of the present invention, when the object to be imaged moves relative to the CT imaging system (for example, the transport mechanism drives the object to be imaged to move), the q target points included in at least one of the M distributed ray sources are arranged obliquely relative to the first direction z, that is, there is a certain angle between the arrangement direction of the target points and the first direction z (see Fig.13A The angle θ in the image can reduce or even avoid motion artifacts, thereby improving imaging quality.

[0176] In an embodiment of the present invention, the CT imaging system 300 further includes a controller, which is configured to control the beam emission interval time of multiple target points and control the moving speed of the object to be imaged.

[0177] like Fig.13A As shown, the q target points 3011 of the distributed ray source may be arranged at intervals along the first straight line L1. For example, the inclination angle θ of the first straight line L1 relative to the first direction z may satisfy the following relationship:

[0178] cosθ=v*t / s (2)

[0179] Wherein, s is the interval distance between two adjacent target points among the q target points along the extension direction of the first straight line L1, v is the moving speed of the object to be imaged, and t is the beam emission interval time of the distributed ray source.

[0180] like Fig.13A As shown, within the beam-emitting interval time t, the moving distance of the object to be imaged 70 along the first direction z is v*t. The i-th target point and the i+1-th target point are two adjacent target points, and the distance between them along the extension direction of the first straight line L1 is s. In the process of the object to be imaged 70 moving along the first direction z, the i-th target point and the i+1-th target point emit beams in sequence according to the beam-emitting interval time t, and by setting s*cosθ=v*t, the rays emitted by the i-th target point and the i+1-th target point scan the same cross section of the object to be imaged 70 perpendicular to the first direction z. In other words, when imaging the moving object to be imaged 70, by designing the inclination angle of the target point, the distance between the target points, the beam-emitting time interval and the moving speed, the multiple target points and the object to be imaged are in a relatively static state along the moving direction, so as to obtain a higher spatial resolution of the current scanning area.

[0181] Fig. 13B Schematic diagram of a distributed ray source of a CT imaging system according to some other exemplary embodiments of the present invention.

[0182] According to the embodiments of the present invention, the tilted arrangement of the target point relative to the first direction z can be achieved through different design methods, thereby obtaining an inclined target point.

[0183] Reference Fig.13A and Fig. 13B The distributed radiation source 310 includes a radiation source body 3012 and q target points 3011 installed on the radiation source body.

[0184] like Fig.13A As shown, the ray source body 3012 may be perpendicular to the first direction z, that is, the two surfaces ( Fig.13A The q target points 3011 installed on the ray source body are relative to the two surfaces ( Fig.13A The upper surface and the lower surface of the ray source are arranged obliquely, so that the q target points 3011 are arranged obliquely relative to the first direction z. In this embodiment, the multiple target points can be flexibly arranged obliquely relative to the ray source body to improve the design freedom of the system.

[0185] like Fig. 13B As shown, the q target points 3011 installed on the radiation source body are relative to the two surfaces of the radiation source body 3012 along the first direction z ( Fig.13A The ray source body 3012 may be arranged in an inclined manner relative to the first direction z, that is, the two surfaces ( Fig.13AThe upper surface and the lower surface of the q target points 3011 are arranged tilted relative to the first direction z. In this way, the q target points 3011 are arranged tilted relative to the first direction z. In this embodiment, the entire ray source body can be tilted directly, which is more convenient and easier to ensure the tilt consistency of all target points.

[0186] In the embodiment of the present invention, the q target points 3011 of the M distributed ray sources 310 may also be arranged obliquely relative to the first direction z. The oblique arrangement of the q target points of each distributed ray source can better adapt to the geometric shape and motion state of the object to be imaged.

[0187] In an embodiment of the present invention, the q target points 3011 of the M distributed ray sources 310 may also have equal inclination angles relative to the first direction z. The equal inclination angles of the q target points of each distributed ray source can ensure that the ray source provides consistent coverage in the entire imaging area.

[0188] In an embodiment of the present invention, the q target points 3011 of the M distributed ray sources 310 may respectively have z-direction position coordinates in the first direction z. The z-direction position coordinates of the i-th target point of the M distributed ray sources 310 may be equal to each other; the z-direction position coordinates of the i-th target point of the M distributed ray sources 310 may also be unequal to each other, 1≤i≤q. That is, according to specific imaging requirements, the z-direction position of the target point may be adjusted to optimize the projection angle and distribution density of the ray.

[0189] Furthermore, the controller can be configured to control the M distributed ray sources 310 to emit beams at the same time at multiple targets with equal z-direction position coordinates. Equal z-direction coordinate positions mean that these targets are located at the same horizontal plane in the z direction, or they are located at the same height of the CT scanning area. Therefore, this design can ensure that the rays emitted by these targets pass through the same imaging section, thereby ensuring that multi-angle data of the same section can be collected at the same time, which helps to improve the details and accuracy of the cross-sectional image and can also reduce blurring and distortion caused by object movement.

[0190] In the embodiment of the present invention, the detector 402 may further include a second sub-detector 4022 . In the first direction z, at least one side of at least one distributed ray source 310 is provided with at least one second sub-detector 4022 .

[0191] FIG. 13C to FIG. 13E Schematic diagrams showing the arrangement of the distributed ray source and the second sub-detector according to some embodiments of the present invention are shown respectively, wherein: Fig. 13C It shows that the second sub-detector is arranged on both sides of the distributed ray source. Fig.13D It shows that a second sub-detector is arranged on the upper side of the distributed ray source. Fig.13EIt is shown that a second sub-detector is arranged at the lower side of the distributed ray source.

[0192] Reference Fig. 13C , in the first direction z, on the first side and the second side of the distributed ray source ( Fig. 13C A second sub-detector 4022 is provided on each of the upper and lower sides (in the middle, respectively).

[0193] Reference Fig.13D , in the first direction z, on only the first side 211 ( Fig.13D A second sub-detector 4022 is provided (in the middle, on the upper side).

[0194] Reference Fig.13E , in the first direction z, on only the second side 212 ( Fig.13E A second sub-detector 4022 is provided (in the middle, on the lower side).

[0195] In an embodiment of the present invention, multiple target points of at least one distributed ray source are arranged obliquely relative to the first direction z. In addition, in the first direction z, at least one second sub-detector 4022 is arranged on the first side 210 of M' distributed ray sources; or, in the first direction z, at least one second sub-detector 4022 is arranged on the second side 212 of M' distributed ray sources; or, in the first direction z, at least one second sub-detector 4022 is arranged on the first side 211 and the second side 212 of M' distributed ray sources, respectively, wherein M' is greater than or equal to 1 and less than or equal to M.

[0196] In this embodiment, by tilting the multiple target points of the distributed ray source and setting the second sub-detector 4022, the position of the second sub-detector can be flexibly arranged to work better with the first detector 4021, and the rays from the distributed ray source can be received from different angles or positions, thereby expanding the detection range. This three-dimensional spatial arrangement breaks through the traditional design of circumferential arrangement, allowing the CT imaging system to detect from multiple angles at the same time, improving the accuracy and breadth of detection, thereby effectively solving the limited angle scanning problem and data truncation problem.

[0197] For example, N2=2M, that is, the number of second sub-detectors N2 can be equal to twice the number of distributed ray sources, that is, a second sub-detector is set on both sides of each distributed ray source. Through such a setting, the detection range can be expanded for each distributed ray source, and the accuracy and breadth of detection can be better improved, so that the limited angle scanning problem and data truncation problem can be more effectively solved.

[0198] Fig.14AA schematic diagram showing a second sub-detector arrangement according to some embodiments of the present invention is shown. Fig. 14B Schematic diagrams showing arrangements of second sub-detectors according to other embodiments of the present invention.

[0199] Reference FIG. 13C to FIG. 13E In the case where the ray source body 3012 is arranged perpendicular to the first direction z, the second sub-detector 4022 may be arranged perpendicular to the first direction z. In other words, the ray source body 3012 and the second sub-detector 4022 are arranged in parallel.

[0200] Reference Fig.14A In the case where the ray source body 3012 is arranged obliquely relative to the first direction z, the second sub-detector 4022 can be arranged parallel to the ray source body 3012, that is, the second sub-detector 4022 is arranged obliquely relative to the first direction z. In other words, both surfaces of the second sub-detector 2022 in the first direction z are arranged obliquely relative to the first direction z.

[0201] Reference Fig. 14B When the ray source body 3012 is arranged obliquely relative to the first direction z, the second sub-detector 4022 may not be arranged parallel to the ray source body 3012, and at least one of the two surfaces of the second sub-detector 4022 in the first direction z is perpendicular to the first direction z.

[0202] According to an embodiment of the present invention, the selection of an inclined arrangement or a vertical arrangement depends on the specific imaging target, the nature of the object and the desired imaging effect. The arrangement of the second sub-detector tilted at a certain angle relative to the first direction z can optimize the detector's coverage of a specific area, especially in scenes where the motion trajectory of a dynamic object or an irregular shape needs to be captured, but may require more complex calibration and algorithm adjustment; the vertical arrangement is usually simpler, easy to implement, and does not require complex angle calibration.

[0203] It should be noted that in the CT imaging system 300 provided in the embodiment of the present invention, its technical solution can be combined with the relevant features in the CT imaging system 200, and this combination is not limited by specific forms and methods, and aims to achieve better technical effects through a variety of possible combinations. On this basis, the mutual combination between the two systems can be flexibly adjusted and optimized according to the actual application scenario.

[0204] An embodiment of the present invention further provides an imaging method of a CT imaging system. Fig.15 A flow chart of an imaging method of a CT imaging system according to some exemplary embodiments of the present invention is shown.

[0205] like Fig.15As shown, the imaging method may include steps S110-S140. It should be noted that steps S110-S140 are not a limitation on the order of the imaging method. In the absence of conflict, the imaging method may be executed in parallel or in a sequence different from that described in the text.

[0206] In step S110 , the object to be imaged is placed in an imaging channel.

[0207] In an embodiment of the present invention, the object to be imaged may be controlled to move at a predetermined moving speed in the imaging channel.

[0208] In step S120, q target points of at least one distributed ray source among the M distributed ray sources are controlled to emit ray beams according to a predetermined beam emitting sequence and a predetermined beam emitting time interval to form an imaging area.

[0209] Further, in order to reduce image artifacts caused by object motion, on the basis of the CT imaging system 300, that is, on the basis that the q target points included in at least one of the M distributed ray sources are arranged tilted relative to the first direction z, the beam-emitting interval time can be controlled to ensure the continuity of image acquisition. Specifically, the beam-emitting interval time can be determined based on the tilt angle of the q target points tilted relative to the first direction z.

[0210] In an embodiment of the present invention, at the same time, only one of the M distributed ray sources may generate X-rays. Alternatively, the same distributed ray source may have multiple targets generating X-rays at the same time. Alternatively, multiple distributed ray sources may generate X-rays at the target at the same position at the same time.

[0211] Exemplarily, when the object to be imaged is located in the imaging area, the k-th target point of at least two of the M distributed ray sources can be controlled to emit beams simultaneously, 1≤k≤q. Here, "simultaneous beam emission" means that during the imaging process, the emission of the ray beam can be accurately controlled within milliseconds or shorter, so as to control the target points of at least two or more of the M distributed ray sources to emit ray beams at almost the same time. The simultaneous beam emission method can acquire a large amount of data in a very short time, thereby significantly reducing the imaging time.

[0212] Fig.16 A schematic diagram of a projection surface of a CT imaging system with multiple target points emitting beams simultaneously according to some exemplary embodiments of the present invention is shown.

[0213] like Fig.16As shown, when the object to be imaged is located in the imaging area, the multiple target points can be controlled to emit beams according to the following beam emission sequence: when j takes values ​​from 1 to q-1 in sequence, the jth target point of the M distributed ray sources emits beams at the same time; then, the j+1th target point of the M distributed ray sources emits beams at the same time. In the first direction z, the j+1th target point is located at the downstream side of the jth target point.

[0214] For example, the beam-out sequence may be: the first target of all distributed ray sources, the second target of all distributed ray sources, and so on. The first and the second are only used to indicate the positional relationship between ray sources or targets. The beam-out time interval may be determined based on the following relationship:

[0215] t=s*cosθ / v (3)

[0216] Wherein, t is the beam-emitting time interval, s is the interval distance between two adjacent target points among the q target points, v is the moving speed, and θ is the inclination angle of the q target points relative to the first direction.

[0217] In an embodiment of the present invention, when the object to be imaged is located in the imaging area, the kth target point of at least two of the M distributed ray sources can also be controlled to emit beams in time. Among them, "time-sharing beam emission" corresponds to "simultaneous beam emission", which means that during the imaging process, the ray beams of different distributed ray sources can be emitted in sequence according to a predetermined beam emission sequence and a predetermined beam emission time interval, so as to separate the beam emission of the rays in the time dimension. The beam emission mode of time-sharing beam emission can reduce mutual interference between different ray beams, reduce signal overlap and noise, and thus improve the clarity and contrast of imaging.

[0218] Fig.17 A schematic diagram of a projection surface of multi-target time-sharing beam output of a CT imaging system according to some embodiments of the present invention is shown.

[0219] like Fig.17 As shown, when the object to be imaged is located in the imaging area, the beam emission of multiple target points can be controlled according to the following beam emission sequence: when j takes values ​​from 1 to q-1 in sequence, the j-th target point of the M distributed ray sources emits beams in sequence in a time-sharing manner; then, the j+1-th target point of the M distributed ray sources emits beams in sequence in a time-sharing manner, wherein in the first direction, the j+1-th target point is located on the downstream side of the j-th target point.

[0220] For example, the beam-emitting sequence may be: the first target of the first distributed ray source, the first target of the second distributed ray source, ..., the first target of the Nth distributed ray source, the second target of the first distributed ray source, the second target of the second distributed ray source, ..., the second target of the Nth distributed ray source, and so on. The beam-emitting time interval may be determined based on the following relationship:

[0221] t=s*cosθ / (M*v) (4)

[0222] Wherein, t is the beam-emitting time interval, s is the interval distance between two adjacent target points among the q target points, v is the moving speed, and θ is the inclination angle of the q target points relative to the first direction.

[0223] In the embodiment of the present invention, the beam emission time interval satisfies: within the imaging time, along the first direction, the q target points and the object to be imaged are in a relatively static state, so as to obtain a higher spatial resolution of the current scanning area.

[0224] By controlling the tilt of the ray source, multiple ray beams can scan the same cross section during the movement of the object. In this way, although the position of the object in space has changed, a relatively "static" perspective is captured during the imaging process because the ray is always aligned with a specific part of the object. Therefore, this relative static state ensures that the captured image will not shift in position due to the movement of the object during the imaging process. When the ray is always irradiated on the same interface or path of the object, the continuity of image acquisition is maintained, thereby greatly reducing artifacts caused by motion.

[0225] In the embodiment of the present invention, the beam emission time interval of the CT imaging system can reach the microsecond level; the single acquisition time of the detector can be 30-150 microseconds; and the imaging resolution of the imaging method can be 1-30 milliseconds.

[0226] In step S130, at least one detector is used to detect rays emitted from at least one distributed ray source and passing through the object to be imaged, and projection data is generated according to the detected rays.

[0227] In the embodiments of the present invention, when the radiation passes through the object to be imaged, tissues or substances of different densities and compositions will have different effects on the absorption and scattering of the radiation, and will be converted into projection data. These data are two-dimensional representations of the internal structure of the object, and contain information about the imaging object from different angles.

[0228] In step S140, a computer tomography image of the object to be imaged is generated based on the projection data. An algorithm (such as back-projection, iterative reconstruction, etc.) can be used to convert the two-dimensional projection data into a three-dimensional image.

[0229] In an embodiment of the present invention, by adopting a predetermined beam-out sequence and time interval determined based on the tilt angle of the target relative to the first direction, accurate timing control and data acquisition of the imaging process are achieved. The tilted target and the precise beam-out time interval can provide richer angle data, increase data redundancy, and facilitate subsequent image reconstruction and artifact reduction. The imaging method provided by the present invention not only significantly improves the imaging accuracy and quality, optimizes the synchronization of beam-out and data acquisition in dynamic imaging, but also effectively reduces image distortion and artifacts caused by object movement.

[0230] Fig.18A It is an image obtained using an imaging system and imaging method in the relevant technology. Fig.18B It is an image obtained by using the imaging system and imaging method provided by the embodiment of the present invention. Fig.18A and Fig.18B In an embodiment of the present invention, during the imaging time, along the first direction, the q target points and the object to be imaged are in a relatively static state, which can better avoid motion artifacts and obtain a higher quality image.

[0231] Fig.19 A block diagram of an electronic device suitable for implementing the method described above according to an embodiment of the present invention is schematically shown. Fig.19 The electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0232] like Fig.19 As shown, the electronic device 1900 according to an embodiment of the present invention includes a processor 1901, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 1902 or a program loaded from a storage part 1908 into a random access memory (RAM) 1903. The processor 1901 may include, for example, a general-purpose microprocessor (e.g., a CPU), an instruction set processor and / or a related chipset and / or a special-purpose microprocessor (e.g., an application-specific integrated circuit (ASIC)), etc. The processor 1901 may also include an onboard memory for caching purposes. The processor 1901 may include a single processing unit or multiple processing units for performing different actions of the method flow according to an embodiment of the present invention.

[0233] In RAM1903, various programs and data required for the operation of electronic device 1900 are stored. Processor 1901, ROM1902 and RAM1903 are connected to each other via bus 1904. Processor 1901 performs various operations of the method flow according to an embodiment of the present invention by executing the program in ROM1902 and / or RAM1903. It should be noted that the program can also be stored in one or more memories other than ROM1902 and RAM1903. Processor 1901 can also perform various operations of the method flow according to an embodiment of the present invention by executing the program stored in the one or more memories.

[0234] According to an embodiment of the present invention, the electronic device 1900 may further include an input / output (I / O) interface 1905, which is also connected to the bus 1904. The electronic device 1900 may further include one or more of the following components connected to the input / output (I / O) interface 1905: an input portion 1906 including a keyboard, a mouse, etc.; an output portion 1907 including a cathode ray tube (CrT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage portion 1908 including a hard disk, etc.; and a communication portion 1909 including a network interface card such as a LAN card, a modem, etc. The communication portion 1909 performs communication processing via a network such as the Internet. A drive 1910 is also connected to the input / output (I / O) interface 1905 as needed. A removable medium 1911, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 1910 as needed, so that a computer program read therefrom is installed into the storage portion 1908 as needed.

[0235] According to an embodiment of the present invention, the method flow according to an embodiment of the present invention can be implemented as a computer software program. For example, an embodiment of the present invention includes a computer program product, which includes a computer program carried on a computer-readable storage medium, and the computer program contains a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication part 1909, and / or installed from the removable medium 1911. When the computer program is executed by the processor 1901, the above-mentioned functions defined in the system of the embodiment of the present invention are executed. According to an embodiment of the present invention, the system, equipment, device, module, unit, etc. described above can be implemented by a computer program module.

[0236] The present invention also provides a computer-readable storage medium, which may be included in the device / apparatus / system described in the above embodiment; or may exist independently without being assembled into the device / apparatus / system. The above computer-readable storage medium carries one or more programs, and when the above one or more programs are executed, the method according to the embodiment of the present invention is implemented.

[0237] According to an embodiment of the present invention, the computer-readable storage medium may be a non-volatile computer-readable storage medium. For example, it may include but is not limited to: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EEPROM or flash memory), a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, an apparatus or a device.

[0238] For example, according to an embodiment of the present invention, the computer-readable storage medium may include the ROM 1902 and / or the RAM 1903 described above and / or one or more memories other than the ROM 1902 and the RAM 1903 .

[0239] An embodiment of the present invention also includes a computer program product, which includes a computer program, and the computer program contains program code for executing the method provided by the embodiment of the present invention. When the computer program product runs on an electronic device, the program code is used to enable the electronic device to implement the method provided by the embodiment of the present invention.

[0240] When the computer program is executed by the processor 1901, the above functions defined in the system / device of the embodiment of the present invention are executed. According to the embodiment of the present invention, the system, device, module, unit, etc. described above can be implemented by a computer program module.

[0241] In one embodiment, the computer program may rely on tangible storage media such as optical storage devices, magnetic storage devices, etc. In another embodiment, the computer program may also be transmitted and distributed in the form of signals on a network medium, and downloaded and installed through the communication part 1909, and / or installed from a removable medium 1911. The program code contained in the computer program may be transmitted using any appropriate network medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0242] According to an embodiment of the present invention, the program code for executing the computer program provided by the embodiment of the present invention can be written in any combination of one or more programming languages. Specifically, these computing programs can be implemented using high-level process and / or object-oriented programming languages, and / or assembly / machine languages. Programming languages ​​include, but are not limited to, such as Java, C++, qython, "C" language or similar programming languages. The program code can be executed completely on the user computing device, partially on the user device, partially on the remote computing device, or completely on the remote computing device or server. In the case of a remote computing device, the remote computing device can be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computing device (for example, using an Internet service provider to connect through the Internet).

[0243] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. In this regard, each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions. It can be understood by those skilled in the art that the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways, even if such a combination or combination is not explicitly recorded in the present invention. In particular, without departing from the spirit and teachings of the present invention, the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways. All these combinations and / or combinations fall within the scope of the present invention.

[0244] The embodiments of the present invention are described above. However, these embodiments are only for the purpose of illustration, and are not intended to limit the scope of the present invention. Although each embodiment is described above, it does not mean that the measures in each embodiment cannot be used in combination advantageously. Without departing from the scope of the present invention, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. An imaging method of a CT imaging system, characterized in that: The CT imaging system comprises: an imaging channel, at least a portion of which extends along a first direction; M distributed ray sources, which are arranged along the circumference of the imaging channel, at least one of which comprises q target points, where M and q are both positive integers greater than or equal to 2; and N detectors, which are arranged along the circumference of the imaging channel, where N is a positive integer greater than or equal to M, wherein the q target points comprised by at least one of the M distributed ray sources are arranged at intervals along a first straight line, and the extension direction of the first straight line is inclined relative to the first direction, The imaging method comprises: placing an object to be imaged in the imaging channel; Controlling q target points of at least one distributed ray source among the M distributed ray sources to emit ray beams according to a predetermined beam emitting sequence and a predetermined beam emitting time interval, and controlling the object to be imaged to move in the imaging channel at a predetermined moving speed to form an imaging area; Using at least one of the detectors to detect radiation emitted from the at least one distributed radiation source and passing through the object to be imaged, and generating projection data based on the detected radiation; and generating a computer tomography image of the object to be imaged according to the projection data, The beam emission time interval is determined based on the inclination angle of the extension direction of the first straight line relative to the first direction and the moving speed. During the imaging time, along the first direction, the q target points and the object to be imaged are in a relatively static state.

2. The imaging method of the CT imaging system according to claim 1, characterized in that: The beam emission time interval is also determined based on the interval distance between two adjacent target points among the q target points.

3. The imaging method of the CT imaging system according to claim 1 or 2, characterized in that: The step of controlling q target points of at least one distributed ray source among the M distributed ray sources to emit ray beams according to a predetermined beam emitting sequence and a predetermined beam emitting time interval comprises: When the object to be imaged is located in the imaging area, the k-th target points of at least two of the M distributed ray sources are controlled to emit beams simultaneously, 1≤k≤q.

4. The imaging method of the CT imaging system according to claim 3, characterized in that: The step of controlling q target points of at least one distributed ray source among the M distributed ray sources to emit ray beams according to a predetermined beam emitting sequence and a predetermined beam emitting time interval comprises: When the object to be imaged is located in the imaging area, multiple target points are controlled to emit beams according to the following beam emission sequence: when j takes values ​​from 1 to q-1 in sequence, the j-th target point of the M distributed ray sources emits beams at the same time; then, the j+1-th target point of the M distributed ray sources emits beams at the same time, wherein in the first direction, the j+1-th target point is located on the downstream side of the j-th target point.

5. The imaging method of the CT imaging system according to claim 3, characterized in that: The imaging method comprises: determining the beam emission time interval based on the following relationship: ， Wherein, t is the beam emission time interval, s is the interval distance between two adjacent target points among the q target points, v is the moving speed, and θ is the inclination angle of the q target points relative to the first direction.

6. The imaging method of the CT imaging system according to claim 1 or 2, characterized in that: The step of controlling q target points of at least one distributed ray source among the M distributed ray sources to emit ray beams according to a predetermined beam emitting sequence and a predetermined beam emitting time interval comprises: When the object to be imaged is located in the imaging area, the k-th target point of at least two of the M distributed ray sources is controlled to emit beams in a time-sharing manner, 1≤k≤q.

7. The imaging method of the CT imaging system according to claim 6, characterized in that: The step of controlling q target points of at least one distributed ray source among the M distributed ray sources to emit ray beams according to a predetermined beam emitting sequence and a predetermined beam emitting time interval comprises: When the object to be imaged is located in the imaging area, multiple target points are controlled to emit beams according to the following beam emission sequence: when j takes values ​​from 1 to q-1 in sequence, the j-th target point of the M distributed ray sources emits beams in sequence in a time-sharing manner; then, the j+1-th target point of the M distributed ray sources emits beams in sequence at the same time, wherein in the first direction, the j+1-th target point is located on the downstream side of the j-th target point.

8. The imaging method of the CT imaging system according to claim 6, characterized in that: The imaging method comprises: determining the beam emission time interval based on the following relationship: ， Wherein, t is the beam emission time interval, s is the interval distance between two adjacent target points among the q target points, v is the moving speed, and θ is the inclination angle of the q target points relative to the first direction.

9. The imaging method of the CT imaging system according to claim 5 or 8, characterized in that: The beam emission time interval reaches microsecond level; and / or, The single acquisition time of the detector is 30-150 microseconds; and / or, The imaging resolution of the imaging method is 1-30 milliseconds.

Images