Multi-source imaging apparatus and method

Abstract

The present disclosure provides a multi-source imaging device and method, the imaging device can include a rotation control mechanism, a plurality of sources, a detection module and an image reconstruction module, the rotation control mechanism is connected with the plurality of sources and the detection module respectively, controls the synchronous rotation of the detection module and the plurality of sources around the rotation center in the imaging process, and the relative position of the detection module and the plurality of sources is unchanged in the rotation process, the emission end of the source is arranged opposite to the receiving end of the detection module, each source is configured to emit a first ray to the detection module in a rotation manner in the rotation process, the detection module receives the first ray after passing through the object to be detected, and forms a projection image according to the received first ray, the image reconstruction module reconstructs the image according to the projection image to obtain a three-dimensional image of the object to be detected, improves the utilization rate and sampling efficiency of the source, meets the heat dissipation requirement of the source, and improves the service life of the source.

Description

Technical Field

[0001] This disclosure relates to the field of X-ray imaging technology, and in particular to a multi-source imaging device and method. Background Technology

[0002] Currently, the main method for scanning target objects using X-rays is to use a radiation generator (source) and a radiation plate detection module. The two are installed and connected by a frame, and the source emits X-rays to the detection module to scan the target object.

[0003] In the process of realizing this disclosure, the inventors discovered that the scanning time of the above-mentioned implementation method is relatively long, and a lot of heat is generated during the scanning process, requiring additional time to dissipate heat, thus resulting in low equipment utilization.

[0004] It should be noted that the information disclosed in this background section is only for understanding the background technology of this disclosure concept, and therefore may contain information that does not constitute prior art. Summary of the Invention

[0005] To address at least one of the aforementioned technical problems, this disclosure provides a multi-source imaging apparatus and method.

[0006] To achieve the above objectives, the first aspect of this disclosure provides a multi-source imaging device, comprising:

[0007] A rotation control mechanism is connected to multiple radiation sources and a detection module. The rotation control mechanism is configured to control the detection module and the multiple radiation sources to rotate synchronously around a rotation center during the imaging process, and the relative position of the detection module and the multiple radiation sources remains unchanged during the rotation.

[0008] The plurality of radiation sources, wherein the emitting ends of the plurality of radiation sources are arranged facing the receiving end of the detection module, and the plurality of radiation sources are configured to emit a first ray toward the detection module in a rotating manner during rotation;

[0009] The detection module is configured to receive the first ray after passing through the object to be tested, and to form a projection image based on the received first ray, wherein the object to be tested is located between the detection module and the plurality of radiation sources;

[0010] The image reconstruction module is configured to perform image reconstruction based on the projected image to obtain a three-dimensional image of the object under test.

[0011] According to one embodiment of this disclosure, the plurality of radiation sources are two radiation sources, and the detection module includes a planar detector, wherein the two radiation sources are arranged horizontally and symmetrically on both sides of the planar detector.

[0012] According to one embodiment of this disclosure, the first ray is an X-ray, and the two sources alternately emit X-rays toward the planar detector during rotation.

[0013] According to one embodiment of this disclosure, the rotation center is the intersection point on the line of intersection of the ray boundaries of the two radiation sources that is farthest from the planar detector.

[0014] According to one embodiment of this disclosure, the rotation angle of the detection module and the two radiation sources around the rotation center is not less than π+max(2γ,β), where γ is the ray range angle formed by the projection of the first ray emitted by the radiation source onto the rotation plane, β is the angle between the rays formed by the projection of the inner boundaries of the rays of the two radiation sources onto the rotation plane, and max is the maximum value function.

[0015] According to one embodiment of this disclosure, on the plane of rotation of the two radiation sources and the planar detector, the distance between the emitting ends of the two radiation sources is equal to the length of the receiving end of the planar detector.

[0016] According to one embodiment of this disclosure, the image reconstruction module performs image reconstruction on the projected image using the FDK algorithm.

[0017] According to one embodiment of this disclosure, when the image reconstruction module performs image reconstruction on the projected image using the FDK algorithm, the scaling factor used during the three-dimensional weighted back projection is:

[0018]

[0019] Where R is the distance between the field of view boundary and the rotation center, max is the maximum value function, γ is the ray range angle formed by the projection of the first ray onto the rotation plane, β is the angle between the rays formed by the projection of the ray boundaries of the two sources onto the rotation plane, and r is the distance between the reconstructed point on the three-dimensional image and the rotation center.

[0020] To achieve the above objectives, a second aspect of this disclosure provides a multi-source imaging method, which is applied to the imaging apparatus described in any of the above embodiments, the method comprising:

[0021] During the imaging process, the detection module and multiple radiation sources are controlled to rotate synchronously around the rotation center, and the relative positions of the detection module and the multiple radiation sources remain unchanged during the rotation.

[0022] The multiple radiation sources are controlled to emit a first ray toward the detection module in a rotating manner during rotation;

[0023] The detection module receives the first ray after it passes through the object to be tested, and forms a projection image based on the received first ray, wherein the object to be tested is located between the detection module and the plurality of radiation sources;

[0024] A three-dimensional image of the object under test is obtained by reconstructing the image based on the projected image.

[0025] According to one embodiment of this disclosure, the first ray is an X-ray, the plurality of sources are two sources, the detection module includes a planar detector, and the two sources alternately emit X-rays toward the planar detector during rotation.

[0026] According to one embodiment of this disclosure, image reconstruction based on the projected image to obtain a three-dimensional image of the object under test includes: image reconstruction of the projected image using the FDK algorithm.

[0027] According to one embodiment of this disclosure, when reconstructing the projected image using the FDK algorithm, the scaling factor used in the three-dimensional weighted back projection is:

[0028]

[0029] Where R is the distance between the field of view boundary and the rotation center, max is the maximum value function, γ is the ray range angle formed by the projection of the first ray onto the rotation plane, β is the angle between the rays formed by the projection of the ray boundaries of the two sources onto the rotation plane, and r is the distance between the reconstructed point on the three-dimensional image and the rotation center.

[0030] This disclosure employs multiple radiation sources for oral image sampling. Compared to single-source sampling, it increases the duty cycle of the pulse signal at the same sampling frequency. When the first radiation source is turned off, the second source can be immediately activated for sampling. This ensures that the first source can cool down while maintaining image sampling, increasing the overall duty cycle and reducing the cooling time of each source. It also guarantees sufficient cooling time for each source, improving source utilization and sampling efficiency, meeting heat dissipation requirements, and extending source lifespan. Furthermore, this disclosure allows for acquiring a larger field of view using a short scanning angle range without changing the detector size, reducing reconstruction time and meeting the clinical needs for short scan times and large fields of view, thus improving sampling quality. Attached Figure Description

[0031] The accompanying drawings illustrate exemplary embodiments of the present disclosure and, together with the description thereof, serve to explain the principles of the present disclosure. These drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification.

[0032] Figure 1 This is a schematic diagram of the positional relationship of a multi-source imaging apparatus according to an embodiment of the present disclosure from a top-down perspective.

[0033] Figure 2 yes Figure 1 A schematic diagram showing the positional relationship between the source and the detection module when they rotate synchronously by an angle β.

[0034] Figure 3 This is a schematic diagram of the positional relationship of a multi-source imaging device according to another embodiment of the present disclosure from a top-down perspective.

[0035] Figure 4 This is a schematic flowchart of a multi-source imaging method according to one embodiment of the present disclosure.

[0036] Figure 5 This is a schematic flowchart of a multi-source imaging method according to another embodiment of the present disclosure.

[0037] The specific labels in the attached figures are as follows:

[0038] 102 - Source, 104 - Detection module, 106 - Area detector. Detailed Implementation

[0039] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the disclosure. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present disclosure are shown in the accompanying drawings.

[0040] It should be noted that, where there is no conflict, the embodiments and features described in this disclosure can be combined with each other. The technical solutions of this disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0041] Unless otherwise stated, the exemplary implementations / embodiments shown are to be understood as providing exemplary features of various details that provide ways in which the technical concepts of this disclosure can be implemented in practice. Therefore, unless otherwise stated, the features of various implementations / embodiments may be additionally combined, separated, interchanged and / or rearranged without departing from the technical concepts of this disclosure.

[0042] The use of crosshairs and / or shading in the accompanying drawings is generally used to clarify the boundaries between adjacent components. Thus, unless otherwise stated, the presence or absence of crosshairs or shading does not convey or indicate any preference or requirement for the specific material, material properties, dimensions, proportions, commonalities between the illustrated components, or any other characteristics, properties, etc., of the components. Furthermore, in the accompanying drawings, the dimensions and relative dimensions of components may be exaggerated for clarity and / or descriptive purposes. When exemplary embodiments can be implemented differently, a specific process sequence may be performed in a different order than that described. For example, two consecutively described processes may be performed substantially simultaneously or in the reverse order of their description. Furthermore, the same reference numerals denote the same components.

[0043] When a component is referred to as being "on" or "above" another component, "connected to," or "joined to" another component, the component may be directly on, directly connected to, or directly joined to the other component, or there may be intermediate components. However, when a component is referred to as being "directly on" another component, "directly connected to," or "directly joined to" another component, there are no intermediate components. Therefore, the term "connection" can refer to a physical connection, an electrical connection, etc., and may or may not have intermediate components.

[0044] For descriptive purposes, this disclosure may use spatial relative terms such as “below,” “under,” “below,” “down,” “above,” “above,” “higher,” and “side (e.g., in a “sidewall”)” to describe the relationship between one component and another component as shown in the accompanying drawings. In addition to the orientations depicted in the drawings, the spatial relative terms are also intended to encompass different orientations of the device during use, operation, and / or manufacture. For example, if the device in the drawings is flipped, a component described as “below” or “under” another component or feature would subsequently be positioned “above” said other component or feature. Thus, the exemplary term “below” can encompass both “above” and “below” orientations. Furthermore, the device may be otherwise positioned (e.g., rotated 90 degrees or in other orientations), thus interpreting the spatial relative descriptive terms used herein accordingly.

[0045] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “the” are intended to include the plural forms as well. Furthermore, when the terms “comprising” and / or “including” and variations thereof are used in this specification, it indicates the presence of the stated features, integrals, steps, operations, parts, components, and / or groups thereof, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, parts, components, and / or groups thereof. It should also be noted that, as used herein, the terms “substantially,” “about,” and other similar terms are used as approximate terms rather than as terms of degree, thus explaining the inherent biases in measurements, calculated values, and / or provided values ​​that would be recognized by one of ordinary skill in the art.

[0046] The multi-source imaging apparatus, method, electronic device, and readable storage medium of this disclosure are described below with reference to the accompanying drawings.

[0047] Figure 1 A schematic diagram showing the positional relationship of a multi-source imaging apparatus according to an embodiment of the present disclosure from a top-down perspective is illustrated. Figure 1 As shown, the multi-source imaging device of this embodiment includes: a rotation control mechanism, multiple sources 102, a detection module 104, and an image reconstruction module.

[0048] The multi-source imaging device 1000 can be applied to various scenarios and fields that require scanning of the test object 202 using high-frequency rays. For example, it can be applied to the field of oral medical imaging, where the user's oral cavity is scanned to obtain an image of the user's oral cavity, and then the oral cavity image is used to analyze the user's oral cavity condition, thus serving as the basis for dental implants and orthodontics.

[0049] The rotation control mechanism is connected to multiple radiation sources 102 and detection modules 104 respectively.

[0050] For example, the rotation control mechanism may include a rotating part and two rotating arms. The rotating part may be mounted on the ground and surround the outer side of the lower part of the user seat. The two rotating arms may be plate-like structures extending upward from the rotating part. Each radiation source 102 is mounted on one of the rotating arms, and the detection module 104 is mounted on the other rotating arm.

[0051] For example, the rotation control mechanism may include a support arm, a rotating part, and two rotating arms. The support arm may be mounted on the ground and located horizontally on one side of the user's seat. The support arm may include a base and a connecting part. The base has an L-shaped structure, with one end mounted on the ground and the other end extending horizontally towards the user's seat. The connecting part may be integrally formed with the other end of the base and may extend from the other end of the base towards the user's seat below. The rotating part is mounted on the bottom of the connecting part and is rotatably connected to it. The two rotating arms may be plate-like structures extending downwards from the rotating part. Each radiation source 102 is mounted on one of the rotating arms, and the detection module 104 is mounted on the other rotating arm.

[0052] The rotation control mechanism is configured to control the detection module 104 and multiple radiation sources 102 to rotate synchronously around the rotation center during the imaging process, and the relative positions of the detection module 104 and multiple radiation sources 102 remain unchanged during the rotation.

[0053] The rotating part is configured to rotate horizontally, and the two rotating arms rotate with the rotation of the rotating part. The center of rotation is point O. The center positions of each radiation source 102 and detection module 104 are approximately the same in the height direction, enabling the two rotating arms to rotate horizontally around the user seat on the outside of the user seat. Each radiation source 102 and detection module 104 can be fixedly mounted on the rotating arm or detachably mounted on the rotating arm, so that each radiation source 102 and detection module 104 can rotate synchronously around the user seat. During the rotation, the distance between each radiation source 102 and detection module 104 remains constant at any given moment.

[0054] The emitting ends of multiple radiation sources 102 are arranged facing the receiving end of the detection module 104, and the multiple radiation sources 102 are configured to emit first rays toward the detection module 104 in a rotating manner during rotation.

[0055] The first beam can be X-rays, and the beams emitted by each source 102 can be cone beams to facilitate the acquisition of oral medical images using CBCT (Cone Beam Computer Tomography). It is understood that the imaging field of cone beam CT is a three-dimensional cylindrical region.

[0056] Each source 102 can use the same model of product, such as Figure 1 As shown, taking the use of two radiation sources 102 as an example, the two radiation sources 102 can be arranged horizontally and symmetrically on both sides of the detection module 104 to form a symmetrical dual-source model. It can be understood that the two radiation sources 102 can also be arranged asymmetrically on both sides of the detection module 104.

[0057] The angle of the ray range formed by the projection of the X-rays emitted by each source 102 onto the plane of rotation is γ. The angle between the rays formed by the projection of the inner boundaries B1 of the rays emitted by the two sources 102 onto the plane of rotation is β. That is, the angle between the boundary lines of the ray range angles formed by the projection of the X-rays emitted by the two sources 102 onto the plane of rotation, and the boundary lines of the two sources 102 that are closer to the opposite source 102, is β.

[0058] The two radiation sources 102 alternately emit X-rays to the detection module 104 during rotation. For example, at time T1, the first radiation source 102 begins emitting X-rays, while the second radiation source 102 is turned off. By time T2, the two radiation sources 102 have rotated a small angle clockwise or counterclockwise, at which point the second radiation source 102 begins emitting X-rays, while the first radiation source 102 is turned off, and so on. Specifically, each radiation source 102 can be exposed sequentially in a pulse mode, and the pulse signals between each radiation source 102 are configured such that their exposure times do not overlap. That is, at most one radiation source 102 has a high-level pulse signal at any given time.

[0059] According to the embodiments of this disclosure, the multi-source imaging device uses multiple sources for oral cavity image sampling. Compared with single-source oral cavity image sampling, it can increase the duty cycle of the pulse signal at the same sampling frequency. When the first source 102 is turned off, the second source 102 can be started immediately for sampling. While ensuring that the first source 102 can be cooled, image sampling can still be carried out. Overall, the duty cycle is increased and the cooling time of the sources is reduced. At the same time, the cooling time of each source 102 can be guaranteed, which improves the utilization rate and sampling efficiency of the source 102, meets the heat dissipation requirements of the source 102, and improves the lifespan of the source.

[0060] The detection module 104 is configured to receive the first ray after passing through the object under test, and to form a projection image based on the received first ray. The object under test is located between the detection module 104 and multiple radiation sources 102.

[0061] The detection module 104 may include a planar detector, and two radiation sources 102 may be arranged horizontally and symmetrically on both sides of the planar detector to receive X-rays. The planar detector may be a flat panel detector.

[0062] The rotation center O can be the intersection point farthest from the surface detector on the intersection line of the ray boundaries of the two radiation sources 102, thereby obtaining the maximum field of view. The user seat is located between each radiation source 102 and the surface detector of the detection module 104, so that the user's oral and maxillofacial region, which is the object to be tested, can be at least partially or entirely located within the projection area (imaging field of view) of the radiation source 102. The X-rays emitted by the radiation source 102 pass through the object to be tested and reach the surface detector. The detection module 104 generates a corresponding two-dimensional projection image based on the X-rays received by the surface detector.

[0063] by Figure 1 Taking counterclockwise rotation as an example, as the rotation control mechanism operates, the two radiation sources 102 and the detection module 104 rotate in a counterclockwise direction. Figure 1 The object rotates in the direction indicated by the dotted arrow, with the rotation amount gradually increasing. Simultaneously, the two radiation sources 102 continuously and alternately emit X-rays. The detection module 104 generates multiple two-dimensional projection images corresponding to different rotation angles based on the X-rays that pass through the object and reach the surface detector at different rotation angles. After the rotation stops, the number of two-dimensional projection images acquired during this rotation process can reach hundreds or more.

[0064] The rotation angle of the detection module 104 and the two radiation sources 102 around the rotation center O can be set to be no less than π+max(2γ,β). Where γ is the angle of the ray range formed by the projection of the X-rays emitted by the radiation source 102 onto the rotation plane, β is the angle between the rays formed by the projection of the inner boundaries of the rays of the two radiation sources 102 onto the rotation plane, and max is the maximum value function.

[0065] When reconstructing an object under test (i.e., the target object to be reconstructed) using CT, every point of the object needs to be scanned 180 degrees. The cone-beam X-ray emission range is fan-shaped on the horizontal plane. Assuming the angle of this fan is 'a', the source 102 and the planar detector need to be rotated around the object under test by an angle of (180° + a) to ensure that every point of the object under test is scanned 180 degrees.

[0066] Figure 2 yes Figure 1 The schematic diagram shows the positional relationship of the radiation source 102 and the detection module 104 when they rotate synchronously by an angle β. Figure 2 This section explains the numerical settings for the rotation angle.

[0067] like Figure 2 As shown, during the rotation of the planar detector 106 and each radiation source around the rotation center O, after a certain period of rotational motion, in Figure 1 The upper-positioned source 102 will emit light from the corresponding... Figure 1The position of the dashed box in the position status is moved to the position of the solid box corresponding to the current moment (rotated by an angle β), as shown by the dotted line arrow. The direction of the X-rays emitted by the source 102 will also change accordingly. The X-rays emitted at the position of the solid box pass through... Figure 2 The solid lines in the diagram represent this. It should be noted that... Figure 1 The middle position on the upper side refers to when viewed at eye level. Figure 1 From the perspective of the upper side, the two radiation sources 102 are arranged horizontally in actual space.

[0068] When source 102 moves from the dashed box position to the solid box position, it is equivalent to coinciding with the position of another source some time ago. At this time, the other source that was at the solid box position some time ago can be combined with source 102 at the solid box position at the current moment and regarded as a virtual source with an emission angle of 2γ. Thus, the scanning results of the two sources 102 can be combined into the scanning data of a single virtual source.

[0069] Since the radiation source 102 needs to rotate by an angle β from the position within the dashed box to the position of another radiation source some time ago, the rotation control mechanism can ensure that the angle requirements for CT reconstruction are met by controlling the area detector 106 and each radiation source 102 to rotate by an angle of (π+2γ+β). The 2γ angle of rotation is used to compensate for any gaps in the fan-shaped beam. However, this overlaps with the radiation angle required for rotating by an angle β, meaning there is scanning redundancy when rotating by an angle of (π+2γ+β). Therefore, rotating by an angle of π+max(2γ,β) is preferable. This satisfies the scanning requirements for the object under test, completely covers the scanning range of the virtual radiation source, and avoids scanning angle redundancy.

[0070] Furthermore, the detection range of the detector corresponding to the virtual radiation source is also expanded. When the radiation source 102 is at the dashed box position, the corresponding position of the area detector 106 is also at the dashed box position; when the radiation source 102 is at the solid box position, the corresponding position of the area detector 106 is also at the solid box position. At this time, the area detector 106 at the dashed box position some time ago can be combined with the radiation source 102 at the solid box position at the current moment, and regarded as a detector with a receiving end length of L2, where L2>L1.

[0071] Understandably, the length of L2 is specifically affected by the position of the radiation source relative to the position of the detector, and the length of L2 can be determined based on the position of each radiation source relative to the detector. For example, when the distance between the transmitting ends of the two radiation sources 102 is the same as the length of the receiving end of the area detector 106, the length L2 of the virtual radiation source is increased to 2cos(γ) times L1. If the distance between the transmitting ends of the two radiation sources 102 is not equal to the length of the receiving end of the area detector 106, then the length L2 of the virtual radiation source is greater than or less than 2cos(γ) times L1.

[0072] Figure 3 A schematic diagram showing the positional relationship of a multi-source imaging apparatus according to another embodiment of the present disclosure from a top-down perspective is illustrated. Figure 3 As shown, on the plane of rotation of the two emission sources 102 and the area detector 106, the distance G between the transmitting ends of the two emission sources 102 is equal to the length L1 of the receiving end of the area detector 106.

[0073] The actual imaging field of view of a multi-source imaging device is a circular region with the rotation center as the center and D*sin(γ) as the radius, where D is the distance from the source 102 to the rotation center O. The CT field of view is mainly related to the length of the planar detector and the distance D between the rotation center and the source 102.

[0074] In single-source 180-degree scanning mode, the distance R from the outer boundary (field of view) of the radiation source 102 to the rotation center O is R = D*sin(γ / 2). R is the range of CT reconstruction, a value derived from the geometric relationship between the radiation source and the area detector; only objects within this range can be reconstructed. R is related to the radiation range angle γ; the larger γ is, the larger the field of view. γ is related to the length L1 of the area detector 106 and the vertical distance SID between the radiation source 102 and the area detector 106. Field of view radius

[0075] like Figure 3 As shown, in dual-source mode, the distance R from the outer boundary B2 (field of view boundary) of the ray from source 102 to the rotation center O is R = D*sin(γ), where γ = arctan(L1 / SID). Therefore, R = D*sin[arctan(L1 / SID)]. Since SID and D are fixed, the field of view radius in dual-source mode is significantly larger than that in single-source mode, which is equivalent to utilizing the entire planar detector, while a single-source 180-degree scan field of view can only utilize half of the planar detector.

[0076] Therefore, when using a single source, the maximum field of view will be less than (L1) / 2 at a rotation angle of (180°+2γ). To fully utilize the detector size to generate a large field of view, a 360-degree rotation is required. Reducing scan time requires minimizing the cost of reconstructing the field of view.

[0077] When using dual sources, the scanning field of view can exceed (L1) / 2 with a rotation angle of 180 degrees plus the included angle β between the two sources. Therefore, compared to a single source, the multi-source imaging device proposed according to the embodiments of this disclosure can acquire a larger field of view using a short scanning angle range without changing the detector size, reducing reconstruction time, while meeting the clinical application requirements for short-time scanning and a large field of view, and improving sampling effect.

[0078] The image reconstruction module is configured to perform image reconstruction based on the projected image to obtain a three-dimensional image of the object under test.

[0079] The image reconstruction module can reconstruct the projected image using the FDK (Feldkamp-Davis-Kress) algorithm. It is understood that the field of view in cone-beam CT imaging is a three-dimensional cylindrical region. When using the FDK reconstruction method, each cross-section on the cylindrical region can be reconstructed using a weighted approximation of the fan-beam reconstruction method. Therefore, only the central cross-section needs to be analyzed and processed.

[0080] The image reconstruction module uses the FDK algorithm to reconstruct projected images, specifically including the following steps: weighting the projected data using a corresponding function to correct the distance and angular difference between the voxel and the source point; performing one-dimensional ramp filtering on the projected images at different rotation angles in the horizontal direction to obtain filtered data; and performing three-dimensional weighted backprojection on the filtered data along the direction of the first ray. Here, the reconstruction point refers to any point on the target object to be reconstructed (e.g., the oral and maxillofacial region). CT reconstruction aims to obtain the X-ray absorption coefficient of each reconstruction point on the target three-dimensional object. It can be understood that the weighting function in the backprojection can be determined based on the distance between the reconstruction point and the focal point, and the reconstructed voxel value can be the sum of the contributions of X-rays from all projection angles passing through that voxel.

[0081] Since the fan-beam projection requires each reconstruction point to be measured 180 degrees, and points on the fan-beam boundary need to be completely scanned within a 180-degree range, the overall rotation must be more than 180 degrees. The closer to the center of the X-ray beam, the greater the measurement redundancy. To improve the numerical accuracy of the reconstruction results, the scaling factor used by the image reconstruction module during 3D weighted backprojection can be:

[0082]

[0083] Where R is the distance between the field of view boundary and the rotation center, max is the maximum value function, γ is the ray range angle formed by the projection of the first ray onto the rotation plane, β is the angle between the rays formed by the projection of the ray boundaries of the two sources onto the rotation plane, and r is the distance between the reconstructed point on the 3D image and the rotation center.

[0084] Figure 4 A schematic flowchart of a multi-source imaging method according to one embodiment of the present disclosure is shown. The multi-source imaging method in this embodiment is implemented based on an embodiment of the multi-source imaging apparatus of the present disclosure.

[0085] The multi-source imaging device includes: a rotation control mechanism, multiple sources, a detection module, and an image reconstruction module.

[0086] The rotation control mechanism is connected to multiple radiation sources and detection modules respectively. The rotation control mechanism is configured to control the detection modules and multiple radiation sources to rotate synchronously around the rotation center during the imaging process, and the relative positions of the detection modules and multiple radiation sources remain unchanged during the rotation.

[0087] The emitting ends of each radiation source are positioned facing the receiving end of the detection module, and each radiation source is configured to emit a first ray toward the detection module in a rotating manner during rotation.

[0088] The detection module is configured to receive the first ray after it passes through the object under test, and to form a projection image based on the received first ray. The object under test is located between the detection module and each ray source.

[0089] The image reconstruction module is configured to perform image reconstruction based on the projected image to obtain a three-dimensional image of the object under test.

[0090] like Figure 4 As shown, the multi-source imaging method S100 of this embodiment may include the following steps.

[0091] S102, during the imaging process, the detection module and multiple radiation sources are controlled to rotate synchronously around the rotation center, and the relative positions of the detection module and multiple radiation sources remain unchanged during the rotation.

[0092] S104 controls multiple radiation sources to emit the first ray to the detection module in a rotating manner during the rotation process.

[0093] S106, the detection module receives the first ray after passing through the object to be tested, and forms a projection image based on the received first ray, wherein the object to be tested is located between the detection module and multiple radiation sources.

[0094] S108, Reconstruct the three-dimensional image of the object under test by performing image reconstruction based on the projected image.

[0095] The first ray can be X-rays, and the multi-source imaging device can be configured with a total of two sources. The detection module can include a planar detector. S104 controls the multiple sources to emit the first ray to the detection module alternately during rotation; specifically, it controls the two sources to alternately emit X-rays to the planar detector during rotation.

[0096] In S108, when reconstructing the three-dimensional image of the object under test based on the projected image, the FDK algorithm can be used to reconstruct the three-dimensional image of the object under test from the projected image. When reconstructing the projected image using the FDK algorithm, the scaling factor used in the three-dimensional weighted back projection is:

[0097]

[0098] Where R is the distance between the field of view boundary and the rotation center, max is the maximum value function, γ is the ray range angle formed by the projection of the first ray onto the rotation plane, β is the angle between the rays formed by the projection of the ray boundaries of the two sources onto the rotation plane, and r is the distance between the reconstructed point on the 3D image and the rotation center.

[0099] It should be noted that for details not disclosed in the multi-source imaging method of this embodiment, please refer to the details disclosed in the multi-source imaging device embodiment of this disclosure, which will not be repeated here.

[0100] Figure 5 A schematic flowchart of a multi-source imaging method according to another embodiment of the present disclosure is shown. Figure 5 As shown, the multi-source imaging method S200 of this embodiment may include the following steps.

[0101] S202 controls the planar detector and two radiation sources to rotate synchronously around the rotation center during the imaging process, and the relative positions of the planar detector and the two radiation sources remain unchanged during the rotation.

[0102] S204 controls two radiation sources to alternately emit X-rays towards the planar detector during rotation.

[0103] S206, the planar detector receives the first ray after passing through the object to be tested, and forms a projection image based on the received first ray, wherein the object to be tested is located between the planar detector and the two ray sources.

[0104] S208 uses the FDK algorithm to reconstruct the three-dimensional image of the object under test.

[0105] It should be noted that for details not disclosed in the multi-source imaging method of this embodiment, please refer to the details disclosed in the multi-source imaging device embodiment of this disclosure, which will not be repeated here.

[0106] In the description of this specification, the references to terms such as "one embodiment / mode," "some embodiments / modes," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment / mode or example is included in at least one embodiment / mode or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment / mode or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments / modes or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments / modes or examples described in this specification, as well as the features of different embodiments / modes or examples.

[0107] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0108] Those skilled in the art should understand that the above embodiments are merely for illustrating the present disclosure and are not intended to limit the scope of the disclosure. Those skilled in the art can make other changes or modifications based on the above disclosure, and these changes or modifications still fall within the scope of the present disclosure.

Claims

1. A multi-source imaging device, characterized in that, include: A rotation control mechanism is connected to multiple radiation sources and a detection module. The rotation control mechanism is configured to control the detection module and the multiple radiation sources to rotate synchronously around a rotation center during the imaging process, and the relative position of the detection module and the multiple radiation sources remains unchanged during the rotation. The plurality of radiation sources, wherein the emitting ends of the plurality of radiation sources are arranged facing the receiving end of the detection module, and the plurality of radiation sources are configured to emit a first ray toward the detection module in a rotating manner during rotation; The detection module is configured to receive the first ray after passing through the object to be tested, and to form a projection image based on the received first ray, wherein the object to be tested is located between the detection module and the plurality of radiation sources; The image reconstruction module is configured to perform image reconstruction based on the projected image to obtain a three-dimensional image of the object under test. The plurality of radiation sources are two radiation sources. The detection module includes a planar detector. The two radiation sources are arranged horizontally and symmetrically on both sides of the planar detector. The rotation angle of the detection module and the two radiation sources around the rotation center is not less than π + max(2γ,β), where γ is the ray range angle formed by the projection of the first ray emitted by the radiation source onto the rotation plane, β is the angle between the rays formed by the projection of the inner boundaries of the rays of the two radiation sources onto the rotation plane, and max is the maximum value function.

2. The apparatus according to claim 1, characterized in that, The first ray is an X-ray, and the two sources alternately emit X-rays toward the planar detector during rotation.

3. The apparatus according to claim 1, characterized in that, The rotation center is the intersection point on the line of intersection of the ray boundaries of the two radiation sources that is farthest from the planar detector.

4. The apparatus according to claim 1, characterized in that, On the plane of rotation of the two radiation sources and the planar detector, the distance between the emitting ends of the two radiation sources is equal to the length of the receiving end of the planar detector.

5. The apparatus according to claim 1, characterized in that, The image reconstruction module reconstructs the projected image using the FDK algorithm.

6. The apparatus according to claim 5, characterized in that, When the image reconstruction module reconstructs the projected image using the FDK algorithm, the scaling factor used during three-dimensional weighted back projection is: Where R is the distance between the field of view boundary and the rotation center, max is the maximum value function, γ is the ray range angle formed by the projection of the first ray emitted by the source onto the rotation plane, β is the angle between the rays formed by the projection of the inner boundaries of the rays of the two sources onto the rotation plane, and r is the distance between the reconstructed point on the three-dimensional image and the rotation center.

7. A multi-source imaging method, characterized in that, The imaging method is applied to the apparatus of any one of claims 1-6, the method comprising: During the imaging process, the detection module and multiple radiation sources are controlled to rotate synchronously around the rotation center, and the relative positions of the detection module and the multiple radiation sources remain unchanged during the rotation. The multiple radiation sources are controlled to emit a first ray toward the detection module in a rotating manner during rotation; The detection module receives the first ray after it passes through the object to be tested, and forms a projection image based on the received first ray, wherein the object to be tested is located between the detection module and the plurality of radiation sources; A three-dimensional image of the object under test is obtained by reconstructing the image based on the projected image.

8. The method according to claim 7, characterized in that, The first ray is an X-ray, the plurality of sources are two sources, the detection module includes a planar detector, and the two sources alternately emit X-rays toward the planar detector during rotation.

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