Device for imaging system, ray filtering device and imaging system

Abstract

The invention relates to a device for an imaging system, a ray filtering device and the imaging system. The apparatus comprises a first filter assembly comprising at least one filter and located on one side of a path of the radiation beam; a second filter assembly including at least one filter and located on the other side of the path of the radiation beam; and a drive system for moving the first filter assembly and the second filter assembly relative to each other to move one filter in the first filter assembly and / or one filter in the second filter assembly into the path of the radiation beam; wherein in the path direction of the radiation beam, the first filter assembly at least comprises a first-layer filter and a second-layer filter which are located at different heights, the second filter assembly at least comprises a third-layer filter, and the third-layer filter and the first-layer filter or the second-layer filter are located at different heights.

Description

Technical Field

[0001] The present invention relates to the field of medical imaging, and in particular to a device used in an imaging system, a ray filtering device and an imaging system. Background Art

[0002] Non-invasive imaging modalities can transmit energy in the form of radiation into an imaging subject. Based on the transmitted energy, an image indicating structural or functional information inside the imaging subject can then be generated. In computed tomography (CT) imaging, radiation is transmitted from a radiation source through an imaging subject to a detector. A ray filter can be positioned between the radiation source and the imaging subject to adjust the spatial distribution of the radiation energy based on the anatomical structure of the imaging subject. The ray filter can be designed to allocate higher radiation energy to a specific imaging area of ​​the subject. Therefore, the amplitude of the signal received by the imaging detector is improved, and the radiation dose around the specific imaging subject is reduced. A bowtie filter is a commonly used ray filter, and different subjects and different anatomical structures of the same subject may require different bowtie filters. For example, bowtie filters of different shapes and sizes can be designed to image subjects of different body shapes or different areas of the subject's body (such as the head, chest, and abdomen). In order to adapt to different scanning requirements, the imaging system needs to be configured with a variety of different types of ray filters, but too many ray filters will make the overall size of the filter device larger and occupy more space. Therefore, a combination of filters can be used to meet the needs. For example, a bowtie filter can be designed for large subjects, and then different shaping or hardening filters can be combined with the bowtie filter to adjust the beam to scan and image subjects of different sizes or different body parts of the same subject. In addition, different functional filters may need to be positioned separately between the radiation source and the detector to adapt to different clinical purposes or to calibrate the imaging system.

[0003] Therefore, a new design of a filter device for integrating a plurality of filters to realize various ray filtering functions is required. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned and / or other problems in the prior art. It provides a new design of a ray filtering device, which can utilize a filter assembly including multi-layer filters disposed on both sides of the path of the radiation beam to achieve multiple ray filtering functions.

[0005] According to a first aspect of the present invention, there is provided a device for an imaging system. The device comprises: a first filter assembly, which comprises at least one filter and is located on one side of a path of a radiation beam; a second filter assembly, which comprises at least one filter and is located on the other side of the path of the radiation beam; and a driving system for moving the first filter assembly and the second filter assembly relative to each other to move a filter in the first filter assembly and / or a filter in the second filter assembly into the path of the radiation beam; wherein in the path direction of the radiation beam, the first filter assembly comprises at least a first layer of filters and a second layer of filters located at different heights, and the second filter assembly comprises at least a third layer of filters, and the third layer of filters is located at a different height from the first layer of filters.

[0006] Preferably, the third layer filter comprises a bowtie filter suitable for filtering the radiation beam when imaging a small object or a child's head.

[0007] Preferably, the first layer of filters includes at least a first filter having a first filtering characteristic and a second filter having a second filtering characteristic, the second layer of filters includes at least a third filter having a third filtering characteristic, and the third layer of filters includes at least a fourth filter having a fourth filtering characteristic.

[0008] Preferably, the first filter and the fourth filter are simultaneously movable into the path of the radiation beam to form a filter combination, wherein the fourth filter is a bow tie filter. Preferably, the first filter is an adult head filter, so that the filter combination is suitable for filtering the radiation beam when imaging an adult head.

[0009] Preferably, the first filter is a shaping filter having a cross-shaped hollow portion, and the radiation beam passes through the cross-shaped hollow portion of the first filter without attenuation.

[0010] Preferably, said fourth filter is adapted to filter said radiation beam when imaging a large object.

[0011] Preferably, the second filter comprises a transfer function correction filter or a blocking filter preventing the radiation beam from penetrating therethrough.

[0012] Preferably, the first layer of filters and the second layer of filters do not overlap in a fan beam width direction of the radiation beam.

[0013] Preferably, the second filter assembly comprises a fourth layer of filters, and the fourth layer of filters and the first layer of filters are located at a different height in the path direction of the radiation beam.

[0014] Preferably, the fourth layer of filters includes at least one filter which does not overlap with the third layer of filters in a fan-beam width direction of the radiation beam.

[0015] Preferably, the third layer filter further comprises a fifth filter having a fifth filtering characteristic, and the fifth filter does not overlap with the fourth filter in the fan beam width direction of the radiation beam.

[0016] Preferably, the third filter and the fourth filter are simultaneously movable into the path of the radiation beam to form a filter combination.

[0017] Preferably, the third filter is adapted to filter the radiation beam when imaging a small object or a child's head.

[0018] Preferably, the fourth filter is an adult head filter, so that the filter combination is suitable for filtering the radiation beam when imaging an adult head.

[0019] Preferably, the fourth filter is a shaping filter having a cross-shaped hollow portion, and the radiation beam passes through the cross-shaped hollow portion of the first filter without attenuation.

[0020] Preferably, the bowtie filter is adapted to filter the radiation beam when imaging large objects.

[0021] According to a second aspect of the present invention, a ray filtering device for an imaging system is provided. The device comprises: a first filter assembly, which comprises at least one filter and is located on one side of the path of a radiation beam; a second filter assembly, which comprises at least one filter and is located on the other side of the path of the radiation beam; and a driving system for moving the first filter assembly and the second filter assembly relative to each other to move a filter in the first filter assembly and / or a filter in the second filter assembly into the path of the radiation beam, wherein in the path direction of the radiation beam, the first filter assembly comprises at least a first layer of filters and a second layer of filters located at different heights, the second filter assembly comprises at least a third layer of filters, and the third layer of filters is located at a different height from the first layer of filters or the second layer of filters; the first layer of filters comprises at least a first filter having a first filtering characteristic and a second filter having a second filtering characteristic; the second layer of filters comprises at least a third filter having a third filtering characteristic; the third layer of filters comprises at least a fourth filter having a fourth filtering characteristic, and the fourth filter can form a combined filter with at least one of the first filter, the second filter or the third filter.

[0022] Preferably, the first layer of filters and the second layer of filters do not overlap in a fan beam width direction of the radiation beam.

[0023] Preferably, the first filter is a shaping filter having a cross-shaped hollow portion, and the radiation beam passes through the cross-shaped hollow portion of the first filter without attenuation.

[0024] Preferably, the first filter and the second filter are installed on the same plane, and the first filter is located between the second filter and the radiation path of the ray.

[0025] Preferably, the first filter and the fourth filter are located together on the path of the radiation beam to form a first combined filter.

[0026] Preferably, the fourth filter is a bowtie filter, and the first combined filter is suitable for filtering the radiation beam when imaging an adult head.

[0027] Preferably, the second filter assembly comprises a fourth layer of filters, and the fourth layer of filters comprises at least one sixth filter which does not overlap with the fourth filter in the fan-beam width direction of the radiation beam.

[0028] Preferably, the sixth filter can form a combined filter with at least one of the first filter, the second filter or the third filter.

[0029] Preferably, the sixth filter can be located together with the third filter on the path of the radiation beam to form a second combined filter.

[0030] According to a third aspect of the present invention, there is provided an imaging system which performs an imaging examination based on a scanning protocol, the imaging system comprising: a gantry for accommodating a scanned object; a radiation source positioned in the gantry for emitting a radiation beam; a detector positioned opposite the gantry relative to the radiation source; a motorized worktable for moving the scanned object within the gantry; an apparatus as described above; and a controller, the controller being configured to control the drive system based on the scanning protocol so that filters in the first filter assembly and / or the second filter assembly that comply with the scanning protocol are moved into the path of the radiation beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention may be better understood by describing exemplary embodiments of the present invention in conjunction with the accompanying drawings, in which:

[0032] Figure 1 An exemplary CT imaging system is shown.

[0033] Figure 2 Shows something like Figure 1 An exemplary imaging system of a CT imaging system.

[0034] Figures 3A-3E is a schematic block diagram of an apparatus 300 for an imaging system according to a first exemplary embodiment of the present invention.

[0035] Figures 4A-4C is a schematic block diagram of an apparatus 400 for an imaging system according to a second exemplary embodiment of the present invention.

[0036] Figure 5 is a schematic block diagram of a ray filtering device 500 for an imaging system according to a third exemplary embodiment of the present invention.

[0037] Figure 6 A schematic diagram showing a shaping filter having a cross-shaped hollow portion.

[0038] Figure 7 is an exemplary structure of a ray filtering device 700 constructed according to the third exemplary embodiment of the present invention.

[0039] Figure 8-Figure 13 Examples of multiple working positions of the ray filtering device 700 are shown respectively. DETAILED DESCRIPTION

[0040] The specific embodiments of the present invention will be described below. It should be noted that in the specific description of these embodiments, in order to provide a concise description, it is impossible for this specification to provide a detailed description of all the features of the actual embodiments. It should be understood that in the actual implementation of any embodiment, just as in the process of any engineering project or design project, in order to achieve the specific goals of the developer and to meet system-related or business-related restrictions, various specific decisions are often made, and this will also change from one embodiment to another. In addition, it can also be understood that although the efforts made in this development process may be complex and lengthy, for ordinary technicians in the field related to the content disclosed by the present invention, some changes such as design, manufacturing or production based on the technical content disclosed in this disclosure are just conventional technical means, and should not be understood as insufficient content of this disclosure.

[0041] Unless otherwise defined, the technical or scientific terms used in the claims and the specification shall have the usual meanings understood by persons with ordinary skills in the technical field to which the invention belongs. The words "first", "second" and similar words used in the patent application specification and the claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "one" or "a" do not indicate a quantitative limitation, but indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalent elements, and do not exclude other elements or objects. Words such as "connect" or "connected" and similar words are not limited to physical or mechanical connections, nor are they limited to direct or indirect connections. "Scanning objects" generally include but are not limited to patients, animals or other objects detected by medical imaging equipment.

[0042] The device for an imaging system provided according to an embodiment of the present disclosure is described in detail below with reference to the accompanying drawings.

[0043] Figure 1 to Figure 2 An exemplary embodiment of an imaging system is shown, wherein the apparatus for an imaging system provided by the disclosed embodiments is positioned between a radiation source and a scanned object. Although a CT system is described by way of example, it should be understood that the techniques of the present invention may also be useful when applied to images acquired using other imaging modalities, such as tomosynthesis, C-arm angiography, etc. The present invention's discussion of the CT imaging modality is provided merely as an example of one suitable imaging modality.

[0044] Various embodiments may be implemented in conjunction with different types of imaging systems. For example, various embodiments may be implemented in conjunction with a CT imaging system, in which a radiation source projects a fan or cone beam that is collimated to lie within the xy plane of a Cartesian coordinate system and is generally referred to as an "imaging plane." The x-ray beam passes through a scanned object, such as a patient. The beam is attenuated by the scanned object and irradiates an array of radiation detectors. The intensity of the attenuated radiation beam received at the detector array depends on the attenuation of the x-ray beam by the scanned object. Each detector element of the array generates a separate electrical signal that is a measure of the beam intensity at the detector position. Intensity measurements from all detectors are collected individually to generate a transmission distribution.

[0045] In third generation CT systems, the radiation source and detector array are rotated in an imaging plane around an object to be imaged (such as a region of a scanned object) using a gantry so that the angle at which the x-ray beam intersects the imaged scanned object is constantly changing. A full gantry rotation occurs when the gantry completes a full 360 degree rotation. A set of x-ray attenuation measurements (e.g., projection data) from the detector array at one gantry angle is called a "view." Thus, a view is each incremental position of the gantry. A "scan" of an object includes a set of views made at different gantry angles or viewing angles during one rotation of the x-ray source and detector.

[0046] In an axial diagnostic scan, the projection data is processed to construct images corresponding to two-dimensional slices taken through the scanned object. A scout scan (also referred to herein as a scout scan) provides projection views along the longitudinal axis of the scanned object and typically provides aggregates, each of which includes the internal structure of the scanned object. A method for reconstructing an image from a set of projection data is known in the art as a filtered backprojection technique. The method converts attenuation measurements from the scan into integers called "CT numbers" or "Houëtsberg units" (HU), which are used to control the brightness of corresponding pixels on a display.

[0047] For detection scans (also referred to herein as positioning scans) and diagnostic scans, beam characteristics such as size, shape, and energy may be different. During certain detection scans and diagnostic scans, it is desirable to use a higher power x-ray source. Higher power improves the quality of diagnostic scans and improves the thermal stability of the x-ray tube including the target. However, the increase in x-ray power can increase the patient's exposure to x-ray radiation. Filters can be used in the path of the beam to attenuate the rays and reduce their energy before the x-ray beam enters the patient's body. It may be particularly desirable to use multiple filters for combined filtering during smaller beams (lower beam coverage), while scans with larger beam coverage can use a single filter. Multiple filters can be mounted on separate brackets that can be moved in and out of the beam as needed. However, adding multiple brackets will increase the cost and complexity of the device. Similarly, since the bracket needs to be moved in and out of the beam between the various parts of the scan, the time to complete the scan may be longer. Therefore, according to the embodiments disclosed herein, the ray filtering device may include filter assemblies arranged on both sides of the path of the radiation beam in the Z direction, and each filter assembly may include one or more filters. Based on the scanning setting, one or more filters from the two filter assemblies can be placed in the path of the radiation beam. By arranging at least one filter assembly to include a multilayer filter, any layer of which can form a combined filter with a filter in another filter assembly, the number of filters (especially bowtie filters) required can be reduced, thereby reducing the cost and complexity of the device.

[0048] Figure 1 An exemplary CT system 100 configured to allow rapid and iterative image reconstruction is shown. Specifically, the CT system 100 is configured to image a scanned object 112 (such as a patient, an inanimate object, one or more manufactured parts) and / or a foreign object (such as a dental implant, a stent, and / or a contrast agent present in the body placed on a movable table 228). In one embodiment, the CT system 100 includes a gantry 102, which in turn may also include at least one x-ray radiation source 104, which is configured to project an x-ray radiation beam 106 for imaging the scanned object 112. The x-ray radiation source 104 includes an x-ray tube and a target. The x-ray tube generates x-rays by accelerating and focusing a high-energy electron beam onto a rotating target. When each electron strikes the target, the energy released by interacting with the atoms of the target isotropically produces x-ray photons under a polychromatic spectrum, and the maximum energy of these x-ray photons matches the maximum energy of the incident electrons. The x-ray photons leave the tube through a window that defines the x-ray beam. The beam can then be collimated and conditioned using collimator blades and one or more filters.

[0049] Specifically, radiation source 104 is configured to project x-rays 106 toward a detector array 108 positioned on an opposite side of gantry 102. Figure 1 Only a single radiation source 104 is depicted, but in some embodiments, multiple radiation sources may be employed to project multiple x-rays 106 to acquire projection data corresponding to the scanned object 112 at different energy levels. The radiation source may include an x-ray target made of graphite and metal.

[0050] In some embodiments, the CT system 100 further includes an image processing unit 110 configured to use an iterative or analytical image reconstruction method to reconstruct an image of a target volume of the scanned object 112. For example, the image processing unit 110 may use an analytical image reconstruction method such as filtered back projection (FBP) to reconstruct an image of the target volume of the scanned object 112. For another example, the image processing unit 110 may use an iterative image reconstruction method such as advanced statistical iterative reconstruction (ASIR), conjugate gradient (CG), maximum likelihood expectation maximization (MLEM), model-based iterative reconstruction (MBIR), etc. to reconstruct an image of the target volume of the scanned object 112.

[0051] Figure 2 Shows something like Figure 1 1. An exemplary imaging system 200 of the CT system 100 of FIG. According to aspects of the present disclosure, the system 200 is configured to perform automatic exposure control in response to user input. In one embodiment, the system 200 includes a detector array 108 (see FIG. Figure 1 ). The detector array 108 also includes a plurality of detector elements 202 that together sense the x-ray beam 106 that passes through a scan object 204 (such as a patient) (see Figure 1 ) to collect corresponding projection data. Therefore, in one embodiment, the detector array 108 is manufactured in a multi-slice configuration including multiple rows of cells or detector elements 202. In such a configuration, one or more additional rows of detector elements 202 are arranged in a parallel configuration for collecting projection data.

[0052] The filter arrangement 240 may be mounted in the gantry 102 between the radiation source 104 and the scanned object 204. The filter arrangement 240 may include filter assemblies disposed on both sides of the path of the radiation beam in the z-direction (described in detail below with reference to FIGS. 3-13 ). The filter assemblies may travel into and out of the beam in the z-direction when the beam is substantially in the y-direction. At least one filter assembly in the filter arrangement 240 may include multiple layers of filters. For example, in Figure 2Two layers of filters are shown in FIG. 2 , an upper filter 241 and a lower filter 242. The lower filter 242 may include a bowtie filter. The bowtie filter is shown here as a rectangular diagram as a schematic diagram, not in actual form. The bowtie filter is rigid and non-deformable. The bowtie filter may alternatively have different shapes and material structures to provide appropriate x-ray special spectra to image various types of anatomical structures. The upper filter 241 may include a functional filter with specific filtering characteristics. The upper filter 241 and the lower filter 242 may belong to the same filter assembly (i.e., the relative position cannot be changed) and be staggered in the Z direction, in which way, either the upper filter 241 or the lower filter 242 may be moved in the Z direction into the path of the radiation beam to filter the radiation beam. The upper filter 241 and the lower filter 242 may also belong to different filter components (i.e., may be movable relative to each other), in which case one or both of the upper filter 241 and the lower filter 242 may be moved in the Z direction into the path of the radiation beam to filter the radiation beam individually or in combination.

[0053] A bowtie filter can change the spatial distribution of a radiation beam in an axial plane of a scanned object (such as a patient). For example, the redistributed radiation beam can have higher energy in the center of the scanned object and lower energy at the periphery of the scanned object. Bowtie filters can be designed to image specific anatomical structures or parts of the human body, such as the head, chest, and abdomen. During imaging, a bowtie filter or filter combination can be selected based on the anatomical structure of the scanned object to be scanned, and the selected filter or filter combination can be placed in the radiation beam path. In response to changes in the anatomical structure, the filter can be changed from one to another. Based on the nature of the scan, the filter assembly can be positioned so that the filter can be placed or not placed in the path of the radiation beam. The filter can attenuate the beam and remove low-energy components, thereby adjusting the beam for a specific scan such as a detection scan.

[0054] The filter drive system can be coupled to each filter assembly of device 240 to move one or more filters into and out of the radiation beam path. In one embodiment, the motor can couple the filter in the bracket by an axis. The filter can be introduced into the beam path or removed from the beam path by utilizing the motor rotating axis to translate the filter along the axis. One of the filters can be selected and translated into the x-ray beam between the radiation source and the scanned object to image a specific part of the human body. The computing device 216 can send a command to the motor of the filter drive system to move the selected filter into the radiation beam. The filter drive system can also send filter position information back to the computing device 216.

[0055] In some embodiments, the system 200 is configured to traverse different angular positions around the scan object 204 to collect the desired projection data. Thus, the gantry 102 and the components mounted thereon (such as the radiation source 104, the filter device 240, and the detector 202) can be configured to rotate around the rotation center 206 to collect, for example, projection data at different energy levels. Alternatively, in embodiments where the projection angle relative to the scan object 204 varies over time, the mounted components can be configured to move along a general arc rather than along a section of a circle.

[0056] In one embodiment, the system 200 includes a control mechanism 208 to control the movement of components, such as the rotation of the gantry 102 and the operation of the x-ray radiation source 104. In certain embodiments, the control mechanism 208 also includes an x-ray controller 210 configured to provide power and timing signals to the radiation source 104. Additionally, the control mechanism 208 includes a gantry motor controller 212 configured to control the rotational speed and / or position of the gantry 102 based on imaging requirements.

[0057] In certain embodiments, the control mechanism 208 also includes a data acquisition system (DAS) 214 that is configured to sample analog data received from the detector elements 202 and convert the analog data into digital signals for subsequent processing. The data sampled and digitized by the DAS 214 is transmitted to a computing device (also referred to as a processor) 216. In one example, the computing device 216 stores the data in a storage device 218. For example, the storage device 218 may include a hard drive, a floppy disk drive, a compact disk-read / write (CD-R / W) drive, a digital versatile disk (DVD) drive, a flash drive, and / or a solid-state storage device.

[0058] In addition, the computing device 216 provides commands and parameters to one or more of the DAS 214, the x-ray controller 210, and the gantry motor controller 212 to control system operations, such as data acquisition and / or processing. In certain embodiments, the computing device 216 controls system operations based on operator input. The computing device 216 receives operator input, which includes, for example, commands and / or scan parameters, via an operator console 220 operatively coupled to the computing device 216. The operator console 220 may include a keyboard or a touch screen to allow an operator to specify commands and / or scan parameters.

[0059] Although Figure 2Only one operator console 220 is shown, but more than one operator console may be coupled to the system 200, e.g., for inputting or outputting system parameters, requesting exams, and / or viewing images. In addition, in certain embodiments, the system 200 may be coupled to multiple displays, printers, workstations, and / or the like located locally or remotely, e.g., within an institution or hospital or at an entirely different location, via one or more configurable wired and / or wireless networks, such as the Internet and / or a virtual private network.

[0060] For example, in one embodiment, the system 200 includes or is coupled to a picture archiving and communication system (PACS) 224. In one exemplary implementation, the PACS 224 is further coupled to a remote system (such as a radiology department information system, a hospital information system) and / or to an internal or external network (not shown) to allow operators at different locations to supply commands and parameters and / or gain access to image data.

[0061] The computing device 216 uses operator-supplied and / or system-defined commands and parameters to operate the table motor controller 226, which in turn can control the motorized table 228. Specifically, the table motor controller 226 moves the table 228 to properly position the scan object 204 in the gantry 102 to acquire projection data corresponding to a target volume of the scan object 204.

[0062] As previously described, the DAS 214 samples and digitizes the projection data acquired by the detector elements 202. Subsequently, the image reconstructor 230 uses the sampled and digitized x-ray data to perform high-speed reconstruction. Figure 2 The image reconstructor 230 is shown as a separate entity, but in certain embodiments, the image reconstructor 230 may form part of the computing device 216. Alternatively, the image reconstructor 230 may not be present in the system 200, and instead the computing device 216 may perform one or more functions of the image reconstructor 230. Furthermore, the image reconstructor 230 may be located locally or remotely, and the image reconstructor 230 may be operably connected to the system 100 using a wired or wireless network. In particular, one exemplary embodiment may use computing resources in a "cloud" network cluster for the image reconstructor 230.

[0063] In one embodiment, the image reconstructor 230 stores the reconstructed image in the storage device 218. Alternatively, the image reconstructor 230 transmits the reconstructed image to the computing device 216 to generate usable patient information for diagnosis and evaluation. In some embodiments, the computing device 216 transmits the reconstructed image and / or patient information to a display 232 that is communicatively coupled to the computing device 216 and / or the image reconstructor 230.

[0064] The present invention provides a device for an imaging system. The device comprises: a first filter assembly, which comprises at least one filter and is located on one side of the path of a radiation beam; a second filter assembly, which comprises at least one filter and is located on the other side of the path of the radiation beam; and a driving system for moving the first filter assembly and the second filter assembly relative to each other to move a filter in the first filter assembly and / or a filter in the second filter assembly into the path of the radiation beam; wherein in the path direction of the radiation beam, the first filter assembly comprises at least a first layer of filters and a second layer of filters located at different heights, and the second filter assembly comprises at least a third layer of filters, and the third layer of filters is located at a different height from the first layer of filters or the second layer of filters. Since the third layer of filters is located at a different height from the first layer of filters or the second layer of filters, the device of the present invention allows the use of filters in the first layer of filters or the second layer of filters combined with filters in the third layer of filters to form a variety of different combined filters to achieve a variety of ray filtering functions.

[0065] First embodiment

[0066] refer to Figures 3A-3E , Figures 3A-3E is a schematic block diagram of an apparatus 300 for an imaging system according to a first exemplary embodiment of the present invention. Figure 3A As shown, the apparatus 300 for an imaging system may include a first filter component 310 , a second filter component 320 , and a driving system 330 .

[0067] The first filter assembly 310 may include at least one filter and is located on one side of the path of the radiation beam 10 ( Figure 3A In the path direction of the radiation beam 10 (i.e., the Y direction), the first filter assembly 310 may include at least a first filter layer 311 and a second filter layer 312 located at different heights. In the present invention, "the first filter layer 311 and the second filter layer 312 are located at different heights in the Y direction" means that the first filter layer 311 and the second filter layer 312 are staggered in the Y direction, that is, the projections on the Y axis do not overlap.

[0068] The second filter assembly 320 may include at least one filter and is located on the other side of the path of the radiation beam 10 ( Figure 3AThe second filter assembly 320 may include at least a third filter 323. In the path direction of the radiation beam 10 (i.e., the Y direction), the third filter 323 is located at a different height from the first filter 311 or the second filter 312, i.e., at least one of the first filter 311 and the second filter 312 is staggered from the third filter 323 in the Y direction, i.e., the projections on the Y axis do not overlap.

[0069] The drive system 330 may be configured to move the first filter assembly 310 and the second filter assembly 320 relative to each other to move one filter in the first filter assembly 310 and / or one filter in the second filter assembly 320 into the path of the radiation beam 10. Specifically, the drive system 330 may be configured to move the first filter assembly 310 in the Z direction so that the radiation beam 10 passes through one filter in the first filter assembly 310, and / or to move the second filter assembly 320 in the Z direction so that the radiation beam 10 passes through one filter in the second filter assembly 320. The drive system 330 may move each of the first filter assembly 310 and the second filter assembly 320 independently.

[0070] In some embodiments of the present invention, the third layer filter 323 is at least located at a different height from the first layer filter 311. The third layer filter 323 and the second layer filter 312 may be located at the same height, or may be located at different heights. Figure 3A In the first exemplary embodiment shown, the third layer filter 323 and the second layer filter 312 can be located at the same height, which means that the third layer filter 323 and the second layer filter 312 are not completely offset in the Y direction, that is, the projections on the Y axis will partially overlap or completely overlap.

[0071] In the imaging system device 300 of the present invention, since the third filter layer 323 and the first filter layer 311 are located at different heights, the filters in the first filter layer and the filters in the third filter layer can be combined to form a variety of different combined filters to achieve a variety of ray filtering functions.

[0072] In some embodiments of the present invention, the first layer filter 311 may include at least a first filter 301 having a first filtering characteristic and a second filter 302 having a second filtering characteristic, the second layer filter 312 may include at least a third filter 303 having a third filtering characteristic, and the third layer filter 323 may include at least a fourth filter 304 having a fourth filtering characteristic.

[0073] In the first exemplary embodiment, the fourth filter 304 may be a bow tie filter. Since the third layer filter 323 (including the fourth filter 304) and the first layer filter 311 (including the first filter 301) are located at different heights in the Y direction, the first filter 301 and the fourth filter 304 can be moved simultaneously into the path of the radiation beam 10 to form a filter combination, such as Figure 3B shown.

[0074] In some embodiments of the present invention, the first filter 301 may be an adult head filter, so that the filter combination is suitable for filtering the radiation beam 10 when imaging an adult head. In this case, the fourth filter 304 may be a bowtie filter suitable for filtering the radiation beam 10 when imaging a small object or a child's head. In this way, imaging of anatomical structures of different morphologies can be achieved using a single bowtie filter, thereby saving the number of bowtie filters.

[0075] In some embodiments of the present invention, the first filter 301 may be a shaping filter 601 having a cross-shaped hollow portion, such as Figure 6 As shown. The radiation beam 10 can pass through the cross-shaped hollow portion 20 of the shaping filter 601 without attenuation. The peripheral portion ( Figure 6 The black area in the figure) can be formed of a material (e.g., tungsten alloy) that can attenuate the radiation beam 10. The shaping filter 601 can form a filter combination with the bowtie filter, so as to be used to filter the radiation beam 10 when performing imaging scanning on a specific anatomical structure of the scanned object. The advantage of the shaping filter 601 is that the radiation beam 10 can be made to pass through the cross-shaped hollow portion 20 to perform imaging scanning on a specific anatomical structure (e.g., heart) of the scanned object, while the peripheral portion can attenuate or absorb the radiation beam 10 to reduce the radiation dose reaching the patient, thereby ensuring the required imaging scanning of the specific anatomical structure of the scanned object while reducing damage to the scanned object.

[0076] In some embodiments of the invention, the fourth filter 304 adapted to be moved into the path of the radiation beam 10 simultaneously with the shaping filter 601 to form a filter combination may be a bowtie filter adapted to filter the radiation beam 10 when imaging large objects.

[0077] In some embodiments of the present invention, the second filter 302 may include a functional filter that can be used alone. As an example, the second filter 302 may be a transfer function correction (TFC) filter for performing correction operations on the imaging system. As an example, the correction operation may be as follows: the radiation beam is emitted from the tube and passes through the TFC filter. The high absorption coefficient material (such as tungsten alloy) on the TFC filter and its sharp edges are expected to leave a projection on the detector. The sharpness of the projection boundary is analyzed to determine the optimization parameters of the tube focus jump design. As another example, the second filter 302 may be a blocking filter that prevents the radiation beam 10 from penetrating therethrough.

[0078] In some embodiments of the present invention, one of the second filter 302, the third filter 303 and the fourth filter 304 can be moved into the path of the radiation beam 10 to filter the radiation beam 10, such as Figure 3C , 3D Or as shown in 3E.

[0079] In some embodiments of the present invention, the filters in the first filter assembly 310 and the second filter assembly 320 may not be located on the path of the radiation beam 10, so that there is a gap between the first filter assembly 310 and the second filter assembly 320 that allows the radiation beam 10 to pass directly, such as Figure 3A shown.

[0080] In some embodiments of the present invention, the first layer filter 311 and the second layer filter 312 may not overlap in the fan beam width direction (Z direction) of the radiation beam 10, which means that the first layer filter 311 and the second layer filter 312 are completely offset in the Z direction, that is, the projections on the Z axis do not overlap.

[0081] In some embodiments of the present invention, the first filter 301 and the second filter 302 may be installed on the same plane. In the Z direction, the first filter 301 may be located between the second filter 302 and the path of the radiation beam 10, and between the third filter 303 and the path of the radiation beam 10. In other words, the first filter 301 may be closer to the path of the radiation beam 10 than the second filter 302 and the third filter 303, and thus may be moved first into the path of the radiation beam 10 to form a filter combination with the fourth filter 304. Although Figure 3A It is shown that the second filter 302 is located between the first filter 301 and the third filter 303 in the Z direction, but the positions of the second filter 302 and the third filter 303 may be swapped in the Z direction.

[0082] Second embodiment

[0083] refer to Figures 4A-4C , Figures 4A-4C 4 is a schematic block diagram of an apparatus 400 for an imaging system according to a second exemplary embodiment of the present invention. Figure 4A As shown, the apparatus 400 for an imaging system may include a first filter component 410 , a second filter component 420 , and a driving system 430 .

[0084] The first filter assembly 410 may include at least one filter and is located on one side of the path of the radiation beam 10 ( Figure 4A In the path direction of the radiation beam 10 (i.e., the Y direction), the first filter assembly 410 may include at least a first filter layer 411 and a second filter layer 412 located at different heights. In the present invention, "the first filter layer 411 and the second filter layer 412 are located at different heights in the Y direction" means that the first filter layer 411 and the second filter layer 412 are staggered in the Y direction, that is, the projections on the Y axis do not overlap.

[0085] The second filter assembly 420 may include at least one filter and is located on the other side of the path of the radiation beam 10 ( Figure 4A The second filter assembly 420 may include at least a third filter 423. In the path direction of the radiation beam 10 (i.e., the Y direction), the third filter 423 is located at a different height from the first filter 411 and the second filter 412, i.e., each of the first filter 411 and the second filter 412 is staggered from the third filter 423 in the Y direction, i.e., the projections on the Y axis do not overlap.

[0086] The drive system 430 may be configured to move the first filter assembly 410 and the second filter assembly 420 relative to each other to move one filter in the first filter assembly 410 and / or one filter in the second filter assembly 420 into the path of the radiation beam 10. Specifically, the drive system 430 may be configured to move the first filter assembly 410 in the Z direction so that the radiation beam 10 passes through one filter in the first filter assembly 410, and / or to move the second filter assembly 420 in the Z direction so that the radiation beam 10 passes through one filter in the second filter assembly 420. The drive system 430 may move each of the first filter assembly 410 and the second filter assembly 420 independently.

[0087] In the device 400 for an imaging system of the present invention, since each of the first layer filter 411 and the second layer filter 412 and the third layer filter 423 are located at different heights, the filters in the first layer filter 411 or the second layer filter 412 can be combined with the filters in the third layer filter 423 to form a variety of different combined filters to achieve a variety of ray filtering functions.

[0088] In some embodiments of the present invention, in the path direction of the radiation beam 10 (i.e., the Y direction), the third layer filter 423 can be located between the first layer filter 411 and the second layer filter 412, so that when the first filter assembly 410 and the first filter assembly 410 move relative to each other, the third layer filter 423 can be inserted between the first layer filter 411 and the second layer filter 412.

[0089] In some embodiments of the present invention, the first filter layer 411 may include at least a first filter 401 having a first filtering characteristic and a second filter 402 having a second filtering characteristic, the second filter layer 412 may include at least a third filter 403 having a third filtering characteristic, and the third filter layer 423 may include at least a fourth filter 404 having a fourth filtering characteristic and a fifth filter 405 having a fifth filtering characteristic. The fourth filter 404 and the fifth filter 405 may not overlap in the fan beam width direction (Z direction) of the radiation beam 10, which means that the fourth filter 404 and the fifth filter 405 are completely staggered in the Z direction, that is, the projections on the Z axis do not overlap.

[0090] In the second exemplary embodiment, since the third layer filter 423 (including the fourth filter 404) and the third layer filter 412 (including the third filter 403) are located at different heights in the Y direction, the third filter 403 and the fourth filter 404 can be moved simultaneously into the path of the radiation beam 10 to form a filter combination, such as Figure 4B shown.

[0091] In some embodiments of the present invention, the fourth filter 404 may be an adult head filter, so that the filter combination is suitable for filtering the radiation beam 10 when imaging an adult head. In this case, the third filter 403 may be a bowtie filter suitable for filtering the radiation beam 10 when imaging a small-sized object or a child's head. In this way, imaging of anatomical structures of different morphologies can be achieved using a single bowtie filter, thereby saving the number of bowtie filters.

[0092] In some embodiments of the present invention, the fourth filter 404 may be a shaping filter 601 having a cross-shaped hollow portion, such as Figure 6As shown. The radiation beam 10 can pass through the cross-shaped hollow portion 20 of the shaping filter 601 without attenuation. The peripheral portion ( Figure 6 The black area in the figure) can be formed of a material (e.g., tungsten alloy) that can attenuate the radiation beam 10. The shaping filter 601 can form a filter combination with the bowtie filter, so as to be used to filter the radiation beam 10 when performing imaging scanning on a specific anatomical structure of the scanned object. The advantage of the shaping filter 601 is that the radiation beam 10 can be made to pass through the cross-shaped hollow portion 20 to perform imaging scanning on a specific anatomical structure (e.g., heart) of the scanned object, while the peripheral portion can attenuate or absorb the radiation beam 10 to reduce the radiation dose reaching the patient, thereby ensuring the required imaging scanning of the specific anatomical structure of the scanned object while reducing damage to the scanned object.

[0093] In some embodiments of the invention, the third filter 403 adapted to be moved into the path of the radiation beam 10 simultaneously with the shaping filter 601 to form a filter combination may be a bowtie filter adapted to filter the radiation beam 10 when imaging large objects.

[0094] In some embodiments of the present invention, the fifth filter 405 may include a functional filter that can be used alone. As an example, the fifth filter 405 may be a transfer function correction (TFC) filter for performing correction operations on the imaging system. As an example, the correction operation may be as follows: the radiation beam is emitted from the tube and passes through the TFC filter. The high absorption coefficient material (such as tungsten alloy) and its sharp edges on the TFC filter are expected to leave a projection on the detector. The sharpness of the projection boundary is analyzed to determine the optimization parameters of the tube focus jump design. As another example, the fifth filter 405 may be a blocking filter that prevents the radiation beam 10 from penetrating therethrough. The fifth filter 405 can be moved into the path of the radiation beam 10 to filter the radiation beam 10, such as Figure 4C shown.

[0095] In some embodiments of the present invention, one of the first filter 401 , the second filter 402 and the third filter 403 may be individually moved into the path of the radiation beam 10 to filter the radiation beam 10 .

[0096] In some embodiments of the present invention, the first layer filter 411 and the second layer filter 412 may not overlap in the fan beam width direction (Z direction) of the radiation beam 10, which means that the first layer filter 411 and the second layer filter 412 are completely offset in the Z direction, that is, the projections on the Z axis do not overlap.

[0097] In some embodiments of the present invention, the fourth filter 404 and the fifth filter 405 may be installed in the same plane. In the Z direction, the fourth filter 404 may be located between the fifth filter 405 and the path of the radiation beam 10. In other words, the fourth filter 404 may be closer to the path of the radiation beam 10 than the fifth filter 405, and thus may be first moved into the path of the radiation beam 10 to form a filter combination with the third filter 403.

[0098] Third embodiment

[0099] refer to Figure 5 , Figure 5 FIG. 5 is a schematic block diagram of a ray filtering device 500 for an imaging system according to a third exemplary embodiment of the present invention. Several details of the ray filtering device 500 are the same as those of the device 300 or 400 described above with respect to FIG. 3-4 , and are not described in detail here. The following mainly describes the special features of the ray filtering device 500. Figure 5 As shown, the ray filtering device 500 for an imaging system may include a first filter component 510 , a second filter component 520 and a driving system 530 .

[0100] The first filter assembly 510 may include at least one filter and be located on one side of the path of the radiation beam 10. In the path direction of the radiation beam 10 (i.e., the Y direction), the first filter assembly 510 may include at least a first upper filter 511 and a first lower filter 512 located at different heights. The first upper filter 511 may include at least a first filter 501 having a first filtering characteristic and a second filter 502 having a second filtering characteristic, and the first lower filter 512 may include at least a third filter 503 having a third filtering characteristic. The first filter 501, the second filter 502, and the third filter 503 may not overlap in the fan beam width direction (Z direction) of the radiation beam 10.

[0101] The second filter assembly 520 may include at least one filter and is located on the other side of the path of the radiation beam 10. The second filter assembly 520 may include a second upper filter 523 and / or a second lower filter 524. The second lower filter 524 may include a fourth filter 504 having a fourth filtering characteristic. The second upper filter 523 may include a fifth filter 505 having a fifth filtering characteristic. The fourth filter 504 and the fifth filter 505 may not overlap in the fan beam width direction (Z direction) of the radiation beam 10.

[0102] In the path direction (i.e., Y direction) of the radiation beam 10, the second upper filter 523 (including the fifth filter 505) is located at different heights from the first upper filter 511 and the first lower filter 512 (including the third filter 503). In this way, the fifth filter 505 can be located together with the third filter 503 on the path of the radiation beam 10 to form a first combined filter.

[0103] In the path direction (i.e., Y direction) of the radiation beam 10, the second lower filter 524 (including the fourth filter 504) is located at a different height from at least the first upper filter 511 (including the first filter 501 and the second filter 502). In this way, the fourth filter 504 can be located together with at least one of the first filter 501 or the second filter 502 on the path of the radiation beam 10 to form a second combined filter.

[0104] In the ray filtering device 500 for an imaging system of the present invention, since the first filter component 510 and the second filter component 520 opposite to each other on both sides of the path of the radiation beam 10 have multilayer filters located at different heights, multilayer filters from different filter components can be combined to form a variety of different combined filters to achieve a variety of ray filtering functions.

[0105] In some embodiments of the present invention, the second upper filter 523 may further include a sixth filter 506 having a sixth filtering characteristic. The fourth filter 504, the fifth filter 505 and the sixth filter 506 may not overlap in the fan beam width direction (Z direction) of the radiation beam 10.

[0106] The drive system 530 can be configured to move the first filter assembly 510 and the second filter assembly 520 relative to each other to move a filter (501 / 502 / 503) in the first filter assembly 510 and / or a filter (504 / 505 / 506) in the second filter assembly 520 into the path of the radiation beam 10.

[0107] In some embodiments of the present invention, the fifth filter 505 may be an adult head filter, so that the first filter combination (fifth filter 505+third filter 503) is suitable for filtering the radiation beam 10 when imaging an adult head. The third filter 503 may be a bowtie filter suitable for filtering the radiation beam 10 when imaging a small object or a child's head. The first filter 501 may be a shaping filter 601 having a cross-shaped hollow portion. The fourth filter 504, which is suitable for moving into the path of the radiation beam 10 simultaneously with the shaping filter 601 to form a second filter combination, may be a bowtie filter suitable for filtering the radiation beam 10 when imaging a large object. In this way, imaging of anatomical structures of different morphologies can be achieved using a single bowtie filter, thereby saving the number of bowtie filters.

[0108] In some embodiments of the present invention, the fifth filter 505 may be a shaping filter 601 having a cross-shaped hollow portion. The third filter 503 adapted to be moved into the path of the radiation beam 10 simultaneously with the shaping filter 601 to form the first filter combination may be a bowtie filter adapted to filter the radiation beam 10 when imaging a large object. The first filter 501 may be an adult head filter, so that the second filter combination (first filter 501 + fourth filter 504) is adapted to filter the radiation beam 10 when imaging an adult head. The fourth filter 304 may be a bowtie filter adapted to filter the radiation beam 10 when imaging a small object or a child's head.

[0109] In some embodiments of the present invention, the second filter 502 or the sixth filter 507 may include functional filters that can be used separately. As an example, the second filter 502 may be a transfer function correction (TFC) filter, and the sixth filter 507 may be a blocking filter that prevents the radiation beam 10 from penetrating therethrough. As another example, the second filter 502 may be a blocking filter that prevents the radiation beam 10 from penetrating therethrough, and the sixth filter 506 may be a transfer function correction (TFC) filter.

[0110] In some embodiments of the present invention, the first filter 501 and the second filter 502 may be installed on the same plane. In the Z direction, the first filter 501 may be located between the second filter 502 and the path of the radiation beam 10, and between the third filter 503 and the path of the radiation beam 10. In other words, the first filter 501 may be closer to the path of the radiation beam 10 than the second filter 502 and the third filter 503, and thus may be first moved into the path of the radiation beam 10 to form a filter combination with the fourth filter 504.

[0111] In some embodiments of the present invention, the fifth filter 505 and the sixth filter 506 may be installed on the same plane. In the Z direction, the fifth filter 505 may be located between the sixth filter 506 and the path of the radiation beam 10, and between the fourth filter 504 and the path of the radiation beam 10. In other words, the fifth filter 505 may be closer to the path of the radiation beam 10 than the sixth filter 506 and the fourth filter 504, and thus may be first moved into the path of the radiation beam 10 to form a filter combination with the third filter 503.

[0112] refer to Figure 7 , Figure 7 is an exemplary structure of a ray filtering device 700 constructed according to a third exemplary embodiment of the present invention, wherein Figure 7 The left side shows an oblique view of the ray filtering device 700. Figure 7 The right side shows a side view of the ray filtering device 700. Several details of the ray filtering device 700 are the same as those of the devices 300, 400 or 500 described above with respect to FIGS. 3-5 and will not be described in detail here. Figure 7 As shown, the ray filtering device 700 may include a first filter component 710, a second filter component 720 and a driving system.

[0113] The first filter assembly 710 may include a first filter 701, a second filter 702, and a third filter 703. In the path direction of the radiation beam 10 (i.e., the Y direction), the first filter 701 and the second filter 702 may be installed in the same plane and located at a different height from the third filter 703. The first filter 701, the second filter 702, and the third filter 703 do not overlap in the fan beam width direction (Z direction) of the radiation beam 10. As an example, the first filter 701 is a shaping filter having a cross-shaped hollow portion, the second filter 702 is a blocking filter that prevents the radiation beam 10 from penetrating therethrough, and the third filter 703 is a first bowtie filter. The first bowtie filter is suitable for filtering the radiation beam 10 when imaging a small-sized object or a child's head.

[0114] The second filter assembly 720 may include a fourth filter 704, a fifth filter 705, and a sixth filter 706. In the path direction of the radiation beam 10 (i.e., the Y direction), the fifth filter 705 and the sixth filter 706 may be installed in the same plane, located in a different plane from the first filter 501 and the second filter 502, and located at a different height from the fourth filter 704. The fourth filter 704, the fifth filter 705, and the sixth filter 706 do not overlap in the fan beam width direction (Z direction) of the radiation beam 10. As an example, the fourth filter 704 is a second bowtie filter, the fifth filter 705 is an adult head filter, and the sixth filter 706 is a TFC filter. The second bowtie filter is suitable for filtering the radiation beam 10 when imaging a large object.

[0115] The first filter assembly 710 may have a first support. The first support has a first body 711, and the first body 711 has a cavity for accommodating the third filter 703. Directly above the third filter 703, the first body 711 has a hollow structure. The first support also has a plurality of first cantilevers 712, each of which extends from both ends of the first body 711 toward the second filter assembly 720 to support the first filter 703 and the second filter 704.

[0116] The ray filtering device 700 may further include a first stationary component 740. The drive system may include a first motor 731 and a first shaft 732. The first motor 731 is fixed to the first stationary component 740. The first shaft 732 is coupled to the first motor 731 and the first filter assembly 710. The first stationary component 740 may be fixed to the frame of the imaging system to remain stationary. The first filter assembly 710 may be moved between a plurality of positions by actuating the first motor 731, thereby moving one of the first filter 701, the second filter 702, and the third filter 703 into or out of the path of the radiation beam 10.

[0117] The second filter assembly 720 may have a second support. The second support has a second body 721, and the second body 721 has a cavity for accommodating the fourth filter 704. The second body 721 has a hollow structure directly above the fourth filter 704. The second support also has a plurality of second cantilevers 722, each of which extends from both ends of the second body 721 toward the first filter assembly 710 to support the fifth filter 705 and the sixth filter 706.

[0118] The ray filtering device 700 may further include a second stationary component 750. The drive system may further include a second motor 733 and a second shaft 734. The second motor 733 is fixed to the second stationary component 750. The second shaft 734 is coupled to the second motor 733 and the second filter assembly 720. The second stationary component 750 may be fixed to the frame of the imaging system to remain stationary. The second filter assembly 720 may be moved between a plurality of positions by actuating the second motor 733, thereby moving one of the fourth filter 704, the fifth filter 705, and the sixth filter 706 into or out of the path of the radiation beam 10.

[0119] See also Figure 8-Figure 13 , which shows examples of multiple working positions of the ray filtering device 700.

[0120] exist Figure 8 In the example of FIG. 7 , the third filter 703 is moved into the path of the radiation beam 10 and the radiation beam 10 is filtered only by the third filter 703 to implement the first ray filtering function. The first ray filtering function is suitable for imaging of small objects or children's heads.

[0121] exist Fig. 9 In the example of FIG. 7 , the second filter 702 is moved into the path of the radiation beam 10 and the radiation beam 10 is filtered only by the third filter 702 to implement the second ray filtering function. The second ray filtering function is suitable for scenarios where the radiation beam 10 does not pass through the device 700 but reaches the scanning area.

[0122] exist Fig.10 In the example of FIG. 1 , the first filter 701 and the fourth filter 704 are moved into the path of the radiation beam 10 and the radiation beam 10 is filtered using the first filter combination formed by the first filter 701 and the fourth filter 704 to implement the third ray filtering function. The third ray filtering function is suitable for imaging processes that require shaping the radiation beam 10 into a cross shape for specific anatomical structures.

[0123] exist Fig.11 In the example of FIG. 1 , the third filter 703 and the fifth filter 705 are moved into the path of the radiation beam 10 and the radiation beam 10 is filtered using the second filter combination formed by the third filter 703 and the fifth filter 705 to implement the fourth ray filtering function. The fourth ray filtering function is suitable for imaging of an adult head.

[0124] exist Fig.12 In the example of FIG. 7 , the sixth filter 706 is moved into the path of the radiation beam 10 and the radiation beam 10 is filtered only by the sixth filter 706 to implement the fifth ray filtering function. The fifth ray filtering function is suitable for the transfer function correction process performed on the imaging system.

[0125] exist Fig.13 In the example of FIG. 7 , the fourth filter 704 is moved into the path of the radiation beam 10 and the radiation beam 10 is filtered only by the fourth filter 704 to implement the sixth ray filtering function. The sixth ray filtering function is suitable for imaging of large objects.

[0126] from Figure 7-13 It can be seen that the ray filtering device 700 of the present invention has the following characteristics: the first filter component 710 and the second filter component 720 are opposite to each other on both sides of the path of the radiation beam 10, and respectively include double-layer filters; the first filter component 710 and the second filter component 720 respectively have four working positions (positions where no filter is located in the path of the radiation beam 10 and positions where three filters are located in the path of the radiation beam 10); the third filter 703 for filtering the radiation beam 10 when imaging a small object or a child's head is arranged on the same side as the first filter 701 that shapes the radiation beam 10 into a cross shape, and a filter 702 is separated in the middle; the adult head filter 705 is designed at the outermost part of the second filter component 720 on the opposite side of the first filter component 710 (including the third filter 703); the third and fourth filters 703 and 704 closest to the drive motor are both designed to be hollowed-out structures; at least 7 types of ray filtering operation functions (the above-mentioned first to sixth ray filtering functions and the radiation beam pass-through function without a filter) can be realized.

[0127] The invention also provides a corresponding imaging system.

[0128] Imaging systems (e.g. Figure 1 The imaging system 100 or 200 in the embodiment of the present invention can perform an imaging examination based on a scanning protocol. The imaging system can include a gantry 102, a radiation source 104, a detector 108, an electric table 228, the apparatus 300 / 400 / 500 / 700 described above, and a controller. The controller can be configured to control the drive system based on the scanning protocol so that the filters in the first filter assembly and / or the second filter assembly that comply with the scanning protocol are moved into the path of the radiation beam.

[0129] So far, the ray filtering device according to the present invention and the imaging system including the same have been described. In the ray filtering device of the present invention, since the first filter assembly and the second filter assembly opposite to each other on both sides of the path of the radiation beam have multilayer filters located at different heights, multilayer filters from different filter assemblies can be combined to form a variety of different combined filters to achieve a variety of ray filtering functions, so as to achieve different clinical purposes and calibration purposes. In addition, the device can reduce the number of bowtie filters required by combining filters, thereby saving costs and device volume. At the same time, the device can have a compact layout in the Z direction, saving space, and is conducive to adapting to various existing or future imaging systems on the market.

[0130] Some exemplary embodiments have been described above. However, it should be understood that various modifications may be made to the exemplary embodiments described above without departing from the spirit and scope of the present invention. For example, if the described techniques are performed in a different order and / or if the components in the described systems, architectures, devices, or circuits are combined in different ways and / or replaced or supplemented by other components or their equivalents, suitable results may be achieved, and accordingly, these modified other implementations also fall within the scope of protection of the claims.

Claims

1. A device for an imaging system, comprising: a first filter assembly comprising at least one filter and located to one side of the path of the radiation beam; a second filter assembly comprising at least one filter and located on the other side of the path of the radiation beam; and a drive system for moving the first filter assembly and the second filter assembly relative to each other to move a filter in the first filter assembly and / or a filter in the second filter assembly into a path of the radiation beam; Wherein in the path direction of the radiation beam, the first filter assembly includes at least a first layer of filters and a second layer of filters located at different heights, and the second filter assembly includes at least a third layer of filters, and the third layer of filters is located at a different height from the first layer of filters.

2. The device according to claim 1, characterized in that The first layer of filters includes at least a first filter having a first filtering characteristic and a second filter having a second filtering characteristic, the second layer of filters includes at least a third filter having a third filtering characteristic, and the third layer of filters includes at least a fourth filter having a fourth filtering characteristic.

3. The device according to claim 2, characterized in that The first filter and the fourth filter are simultaneously movable into the path of the radiation beam to form a filter combination, wherein the fourth filter is a bow-tie filter.

4. The apparatus of claim 3, the first filter being an adult head filter, such that the filter combination is suitable for filtering the radiation beam when imaging an adult head.

5. The device according to claim 2, characterized in that The first filter is a shaping filter having a cross-shaped hollow portion, and the radiation beam passes through the cross-shaped hollow portion of the first filter without being attenuated.

6. The device according to claim 2, characterized in that The second filter includes a transfer function correction filter or a blocking filter that prevents the radiation beam from penetrating therethrough.

7. The device according to claim 1, characterized in that The first layer of filters and the second layer of filters do not overlap in a fan-beam width direction of the radiation beam.

8. The device according to claim 2, characterized in that The second filter assembly includes a fourth layer of filters, which is located at a different height from the first layer of filters in the path direction of the radiation beam.

9. The device according to claim 8, characterized in that The fourth layer of filters includes at least one filter that does not overlap with the third layer of filters in the fan-beam width direction of the radiation beam.

10. The device according to claim 2, characterized in that The third layer of filters further comprises a fifth filter having a fifth filtering characteristic, wherein the fifth filter does not overlap with the fourth filter in a fan-beam width direction of the radiation beam.

11. The device according to claim 2, characterized in that The third filter and the fourth filter are simultaneously moveable into the path of the radiation beam to form a filter combination.

12. The device according to claim 11, characterized in that The fourth filter is a shaping filter having a cross-shaped hollow portion, and the radiation beam passes through the cross-shaped hollow portion of the fourth filter without being attenuated.

13. A ray filtering device for an imaging system, comprising: a first filter assembly comprising at least one filter and located to one side of the path of the radiation beam; a second filter assembly comprising at least one filter and located on the other side of the path of the radiation beam; and a drive system for moving the first filter assembly and the second filter assembly relative to each other to move a filter in the first filter assembly and / or a filter in the second filter assembly into the path of the radiation beam, Wherein, in the path direction of the radiation beam, the first filter assembly comprises at least a first layer of filters and a second layer of filters located at different heights, and the second filter assembly comprises at least a third layer of filters, and the third layer of filters and the first layer of filters are located at different heights; The first layer of filters at least includes a first filter having a first filtering characteristic and a second filter having a second filtering characteristic; The second layer of filters comprises at least a third filter having a third filtering characteristic; The third layer filter includes at least a fourth filter having a fourth filtering characteristic, and the fourth filter can form a combined filter with at least one of the first filter, the second filter or the third filter.

14. The device according to claim 13, characterized in that The first filter is a shaping filter having a cross-shaped hollow portion, and the radiation beam passes through the cross-shaped hollow portion of the first filter without being attenuated.

15. The device according to claim 13, characterized in that The first filter and the second filter are installed on the same plane, and the first filter is located between the second filter and the ray radiation path.

16. The device according to claim 14, characterized in that The first filter and the fourth filter are located together in the path of the radiation beam to form a first combined filter.

17. The device according to claim 13, characterized in that The second filter assembly comprises a fourth layer of filters including at least one sixth filter that does not overlap with the fourth filter in a fan-beam width direction of the radiation beam.

18. The device according to claim 17, characterized in that The sixth filter may form a combined filter with at least one of the first filter, the second filter or the third filter, respectively.

19. The device according to claim 18, characterized in that The sixth filter may be co-located with the third filter in the path of the radiation beam to form a second combined filter.

20. An imaging system, the imaging system performing an imaging examination based on a scanning protocol, the imaging system comprising: A frame for receiving a scan object; a radiation source positioned in the gantry for emitting a radiation beam; a detector positioned opposite the gantry from the radiation source; An electric workbench, the electric workbench is used to move the scanning object in the frame; The device as claimed in any one of claims 1 to 19; and A controller is configured to control the drive system based on the scanning protocol so that filters in the first filter assembly and / or the second filter assembly that comply with the scanning protocol are moved into the path of the radiation beam.

Images