Reference detector for ct scanning and ct imaging apparatus

Abstract

Embodiments of the present specification provide a reference detector for CT scanning and a CT imaging device. The reference detector includes a reference detector main body and a filter plate. The reference detector main body includes a detector pixel array. The detector pixel array is an array composed of a plurality of detector pixels, the detector pixel being a scintillator pixel or a semiconductor pixel, the scintillator pixel including a scintillator and a photodiode. The reference detector main body has two opposite surfaces, one of which is a receiving surface of radiation. The filter plate is disposed on the receiving surface side of the reference detector main body. The filter plate is provided with a plurality of through holes, wherein when the radiation irradiates the reference detector, the radiation reaches the plurality of detector pixels through the plurality of through holes.

Description

Technical Field

[0001] This manual relates to the field of medical imaging, and in particular to reference detectors and CT imaging equipment used for CT scans. Background Technology

[0002] Computed tomography (CT) is a commonly used medical imaging technique. In CT scans, air correction is performed by acquiring data from the scanning air to calibrate the detector response. Ideally, during air correction, light intensity is proportional to the current value (in mA). However, due to hardware limitations, the current value fed back by the CT system has a certain error, resulting in inaccurate calculated light intensity values ​​and thus affecting the quality of the reconstructed image. Typically, a reference detector (RD) is used to acquire the actual light intensity. The reference detector can be the edge channel of the main detector or a separate detector mounted on the proximal side of the CT tube. However, the edge channel is easily obstructed by objects, affecting the quality of the reconstructed image; while a reference detector mounted on the proximal side of the CT tube requires a complex design, resulting in high cost, large space occupation, and poor assembly robustness.

[0003] Therefore, it is desirable to provide a reference detector and CT imaging equipment for CT scans to improve the design of the reference detector while ensuring the quality of the reconstructed images. Summary of the Invention

[0004] One embodiment of this specification provides a reference detector for CT scanning. The reference detector includes a reference detector body and a filter plate. The reference detector body includes a detector pixel array and a signal readout assembly; the detector pixel array includes a plurality of detector pixels. The filter plate is used to cover the detector pixel array. The filter plate has a plurality of through-holes, wherein when radiation irradiates the reference detector, the radiation reaches the plurality of detector pixels through the plurality of through-holes.

[0005] In some embodiments, the filter plate includes a plurality of sub-regions, each sub-region being directly opposite one of the plurality of detector pixels along a first direction, and each sub-region having at least one through hole, the first direction being the incident direction of the radiation.

[0006] In some embodiments, the filter plate is fixedly connected to the detector pixel array.

[0007] In some embodiments, the detector pixel is a scintillator pixel, which includes a scintillator and a photodiode.

[0008] In some embodiments, the detector pixel is a semiconductor pixel.

[0009] One embodiment of this specification provides a reference detector for CT scanning. The reference detector includes a reference detector body and a filter plate. The reference detector body includes a detector pixel array, which is an array composed of multiple detector pixels. Each detector pixel is a scintillator pixel or a semiconductor pixel, and the scintillator pixel includes a scintillator and a photodiode. The reference detector body has two opposing surfaces, one of which is a radiation receiving surface. The filter plate is disposed on one side of the receiving surface of the reference detector body. The filter plate has multiple through-holes, wherein when radiation irradiates the reference detector, the radiation reaches the multiple detector pixels through the multiple through-holes.

[0010] In some embodiments, the detector pixels correspond one-to-one with the vias.

[0011] In some embodiments, the semiconductor pixel is made of cadmium zinc telluride, cadmium telluride, or silicon.

[0012] In some embodiments, the reference detector body further includes a signal readout component, which includes a dedicated readout circuit and a data acquisition board.

[0013] In some embodiments, a support member is provided between the filter plate and the reference detector body to form a gap between the filter plate and the detector pixel.

[0014] One embodiment of this specification provides a CT imaging apparatus, including an X-ray tube, a collimator, a main detector, and a reference detector as described in this embodiment. The X-ray tube is used to generate the radiation. The reference detector is disposed outside the collimator.

[0015] In some embodiments, the reference detector is disposed between the main detector and the collimator. The reference detector and the collimator are connected to the side facing the main detector.

[0016] In some embodiments, the main detector includes a detector pixel array, the detector pixel array of the main detector includes a plurality of detector pixels, and the filter plate of the reference detector includes a plurality of sub-regions, each sub-region having at least one through-hole, the total area of ​​the through-holes in each sub-region satisfying the relationship: S1=S2 (L1 / L2), where S1 is the total area, S2 is the pixel area of ​​each detector pixel on the main detector, L1 is the distance from the focal point of the X-ray tube to the detector pixel array of the reference detector, and L2 is the distance from the focal point of the X-ray tube to the detector pixel array of the main detector.

[0017] In some embodiments, the main detector includes a detector pixel array, which is an array composed of multiple detector pixels. The detector pixels in the main detector are scintillator pixels or semiconductor pixels. The filter plate of the reference detector includes multiple sub-regions, each sub-region having at least one through-hole. The total area of ​​the through-holes in each sub-region satisfies the relationship: S1 = S2. (L1 / L2), where S1 is the total area, S2 is the pixel area of ​​each detector pixel in the main detector, L1 is the distance from the focal point of the X-ray tube to the detector pixel array of the reference detector, and L2 is the distance from the focal point of the X-ray tube to the detector pixel array of the main detector.

[0018] One embodiment of this specification provides a CT imaging apparatus, including a gantry, an X-ray tube, a main detector, a collimator, and a reference detector as described in the embodiments of this specification. The gantry is rotatable. The X-ray tube is disposed within the gantry and is used to generate radiation. The main detector is disposed within the gantry and opposite to the X-ray tube, and is used to receive the radiation after it has passed through the scanned object. The collimator is disposed between the X-ray tube and the main detector, and is used to reduce the scattering of the radiation. The reference detector is disposed between the X-ray tube and the main detector, or between the collimator and the main detector, and is used to receive at least a portion of the radiation that has not passed through the scanned object.

[0019] In some embodiments, the reference detector includes a filter plate and a plurality of detector pixels, the filter plate having at least one through-hole that allows the radiation to pass through and be received by the detector pixels.

[0020] In some embodiments, the filter plate is made of tungsten or titanium.

[0021] In some embodiments, there are multiple vias, and each detector pixel corresponds to one via. The reference detector body of the reference detector includes detector pixels and a signal readout component, and the signal readout component includes a dedicated readout circuit and a data acquisition board.

[0022] In some embodiments, the reference detector includes a plurality of detector pixels, and a high-density and / or high atomic number material is disposed on one side of the receiving surface of the reference detector body of the reference detector, the high-density and / or high atomic number material being used to attenuate the intensity of the radiation received by the detector pixels.

[0023] One embodiment of this specification provides a method for manufacturing a CT imaging device applicable to the embodiments described in this specification. The manufacturing method includes: determining the mounting position of the reference detector; determining the structural parameters of the plurality of through holes based on the mounting position; fabricating the reference detector based on the structural parameters; and installing the fabricated reference detector at the mounting position.

[0024] In some embodiments, the main detector includes a detector pixel array, which is an array composed of multiple detector pixels, and the detector pixels in the main detector are scintillator pixels or semiconductor pixels. The filter plate of the reference detector includes multiple sub-regions, each sub-region having at least one through-hole. Determining the structural parameters of the multiple through-holes based on the installation position includes: determining L2 and S2, where L2 is the distance from the focal point of the X-ray tube to the detector pixel array of the main detector, and S2 is the pixel area of ​​each detector pixel in the main detector; determining L1 based on the installation position, where L1 is the distance from the focal point of the X-ray tube to the detector pixel array of the reference detector; and determining S1 based on L1, L2, and S2, where S1 is the total area of ​​the through-holes in each sub-region.

[0025] One embodiment of this specification provides a computer-readable storage medium that stores computer instructions. When a computer reads the computer instructions from the storage medium, the computer executes the manufacturing method of the CT imaging device described in this embodiment. Attached Figure Description

[0026] This specification will be further described by way of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting; in these embodiments, the same reference numerals denote the same structures, wherein: Figure 1 These are schematic diagrams of exemplary medical imaging systems according to some embodiments of this specification; Figure 2 This is a schematic diagram of an exemplary reference detector for CT scanning according to some embodiments of this specification; Figures 3A-3E This is a schematic diagram of the structure of an exemplary reference detector for CT scanning according to some embodiments of this specification; Figure 4 These are schematic diagrams of exemplary CT imaging apparatuses shown according to some embodiments of this specification; Figure 5 This is a schematic diagram illustrating an exemplary reference detector mounting location according to some embodiments of this specification; Figure 6This is a schematic diagram illustrating an exemplary reference detector mounting location according to some embodiments of this specification; Figure 7 This is a flowchart illustrating a method of manufacturing an exemplary CT imaging device according to some embodiments of this specification; Figure 8 This is a schematic diagram of an exemplary reference detector according to some embodiments of this specification; Figure 9 This is a schematic diagram of an exemplary reference detector according to some embodiments of this specification; Figure 10 This is a schematic diagram of an exemplary CT imaging system according to some embodiments of this specification. Detailed Implementation

[0027] To more clearly illustrate the technical solutions of the embodiments in this specification, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this specification. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0028] It should be understood that the terms “system,” “device,” “unit,” and / or “module” used herein are one way to distinguish different components, elements, parts, sections, or assemblies at different levels. However, if other terms can achieve the same purpose, they may be replaced by other expressions.

[0029] As indicated in this specification and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" do not specifically refer to the singular and may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0030] Flowcharts are used in this specification to illustrate the operations performed by the system according to embodiments of this specification. It should be understood that the preceding or following operations are not necessarily performed in exact order. Instead, the steps can be processed in reverse order or simultaneously. Furthermore, other operations can be added to these processes, or one or more steps can be removed from them.

[0031] Currently, in order to obtain the actual light intensity during CT scans, the actual light intensity passing through the air is usually collected through the edge channel of the main detector during patient scanning, that is, the edge channel of the main detector is used as a reference detector. Figure 8This is a schematic diagram of an exemplary reference detector according to some embodiments of this specification. For example... Figure 8 As shown, the X-rays emitted from the focal point of the CT tube pass through a collimator and filter (e.g., a Bowtie filter) and are directly received by the edge channel of the main detector, thus enabling the acquisition of data that has not passed through the scanned object (e.g., the patient). However, the edge channel may be obstructed by the scanned object or other objects within the aperture (e.g., when scanning a large patient or when the patient is mispositioned, the patient may block the edge channel of the main detector), resulting in data discontinuity, which in turn leads to a decrease in the quality of the reconstructed image or the appearance of significant artifacts.

[0032] An independent reference detector can avoid the problem of object occlusion. An independent reference detector is typically installed proximally to the side of the CT tube, where the X-ray flux is 10²-10 times higher than that of the main detector. 4 A scintillator saturation layer, when applied more than twice the density of the primary detector, can easily cause the reference detector to saturate and fail. This necessitates the addition of a very thick layer of attenuating material (e.g., high-density metals such as aluminum, tungsten, nickel, or iron) to prevent scintillator saturation. However, this leads to a significant difference in the energy spectrum received by the edge channels of the reference and primary detectors, affecting image quality. This difference can be overcome using indirect filtering, where only the reference detector receives scattered light from the filtering material, ensuring consistency between the reference detector's response and the primary detector's edge channel response. This requires designing complex blocking and scattering mechanisms. Figure 9 This is a schematic diagram of an exemplary reference detector according to some embodiments of this specification. For example... Figure 9 As shown, the reference detector is mounted to the side of the X-ray tube focal spot and very close to it. The rays emitted from the CT tube focal spot are directly received by the reference detector. The rays must pass sequentially through a light-shielding slice (e.g., a tungsten plate) and a filter plate (e.g., an aluminum block scattering grating) of the reference detector, becoming scattered light that is received by a scintillator and then converted into an electrical signal by a photodiode. It can be seen that the filter material used to manufacture the filter plate is very thick compared to other components of the reference detector, which greatly increases the space occupied by the reference detector and causes increased costs. Moreover, this reference detector is multi-layered, structurally complex, costly, and difficult to assemble.

[0033] This specification provides a reference detector for CT scanning, a CT imaging device, and a method for manufacturing the same. The reference detector includes a reference detector body and a filter plate. The reference detector body includes a detector pixel array and a signal readout assembly; the detector pixel array includes a plurality of detector pixels. The filter plate is used to cover the detector pixel array. The filter plate has a plurality of through-holes, wherein when radiation irradiates the reference detector, the radiation passes through the plurality of through-holes to reach the plurality of detector pixels.

[0034] According to the embodiments of this specification, by setting multiple through holes on the filter plate of the reference detector, dose attenuation can be achieved through the geometric duty cycle of the through holes (hole area / plate area), avoiding detector flicker and pixel saturation, while maintaining the authenticity of the energy spectrum, thereby ensuring image quality; the complex scattering and blocking structure is eliminated, which greatly reduces the overall size and weight of the reference detector, occupies very little space, and the simplification of the mechanism improves installation flexibility.

[0035] Figure 1 These are schematic diagrams of exemplary medical imaging systems according to some embodiments of this specification. Figure 1 As shown, system 100 includes medical imaging equipment 110, processing equipment 120, storage equipment 130, terminal 140, and network 150.

[0036] Medical imaging equipment 110 refers to a medical device that uses different media to reproduce images of the internal structures of the human body. In some embodiments, medical imaging equipment 110 includes a detector and a radiation source. The radiation source emits X-rays into the human body; the detector detects the X-ray signals passing through the human body and converts them into visible light and then into electrical signals, or the detector detects the X-ray signals passing through the human body and directly converts them into digital signals, and counts each detected X-ray photon to obtain its true energy information. The radiation source includes an X-ray tube, which emits different single-energy or multi-energy X-rays using tube voltages such as 80kV, 100kV, and 140kV. The detector includes types such as amorphous silicon flat panel detectors, amorphous selenium flat panel detectors, cesium iodide scintillation detectors, zinc cadmium telluride semiconductor detectors, cadmium telluride semiconductor detectors, and silicon semiconductor detectors. By way of example only, the medical imaging device 110 may be a single-modal system such as a computed tomography (CT) device, a direct digital radiography (DR) system, a computed radiography (CR) device, or a digital subtraction angiography (DSA) system, or a multimodal system such as a positron emission tomography-computed tomography (PET-CT) device. The medical imaging device 110 described above is for illustrative purposes only and is not intended to limit its scope. The detector in the medical imaging device 110 can receive radiation from a radiation source and measure the received radiation. Throughout this specification, the radiation is described using an X-ray beam emitted from the X-ray tube in a CT device as an example. In some embodiments, the medical imaging device 110 may exchange data and / or information with other components in the system 100 (e.g., processing device 120, storage device 130, terminal 140) via a network 150. In some embodiments, the medical imaging device 110 may be directly connected to other components in the system 100. In some embodiments, one or more components of the system 100 (e.g., processing device 120, storage device 130) may be included within the medical imaging device 110. The medical imaging device 110 includes a main detector, a collimator, and a reference detector, with the reference detector disposed outside or inside the collimator. Examples include main detector 440, main detector 640, CT detector 1040, reference detector 200, reference detector 300, reference detector 610, and reference detector 1020. The main detector is used to quantify the radiation received by the scanned object (e.g., a patient). The reference detector is used to perform air correction on the detector response of the main detector.A reference detector is an auxiliary detector used to monitor changes in X-ray dose and energy in real time. Its signal is used to correct response drift of the main detector and improve the quality of the reconstructed image. In some embodiments, the reference detector includes a reference detector body and a filter plate. The reference detector body includes a detector pixel array and a signal readout assembly. The detector pixel array includes multiple detector pixels. The filter plate is used to cover the detector pixel array. The filter plate has multiple through holes, through which radiation reaches the multiple detector pixels when the reference detector is irradiated.

[0037] Processing device 120 processes data and / or information obtained from other devices or system components, and performs a method for manufacturing a CT imaging apparatus as shown in some embodiments of this specification based on this data, information, and / or processing results to perform one or more functions described in some embodiments of this specification. For example, processing device 120 may determine the mounting location of a reference detector. As another example, processing device 120 may determine the structural parameters of a plurality of vias based on the mounting location. As another example, processing device 120 may fabricate a reference detector based on the structural parameters. As another example, processing device 120 may install the fabricated reference detector at the mounting location.

[0038] In some embodiments, the processing device 120 may include one or more sub-processing devices (e.g., a single-core processing device or a multi-core multi-chip processing device). By way of example only, the processing device 120 may include a central processing unit (CPU), an application-specific integrated circuit (ASIC), a graphics processing unit (GPU), a field-programmable gate array (FPGA), a reduced instruction set computer (RISC), or any combination thereof.

[0039] Storage device 130 stores data or information generated by other devices. For example, storage device 130 may store data and / or information acquired by medical imaging device 110. As another example, storage device 130 may store data and / or information processed by processing device 120. Storage device 130 may include one or more storage components, each of which may be a separate device or part of another device. The storage device may be local or implemented via the cloud.

[0040] Terminal 140 can control the operation of medical imaging equipment 110. For example, a doctor can issue operating instructions to medical imaging equipment 110 through terminal 140, so that medical imaging equipment 110 can irradiate and image a specified part of the patient's body. Terminal 140 can be one of or any combination of mobile devices 140-1, tablet computers 140-2, laptop computers 140-3, desktop computers, and other devices with input and / or output functions.

[0041] Network 150 connects the various components of the system and / or connects the system to external resources. Network 150 enables communication between the components and with other parts outside the system, facilitating the exchange of data and / or information. In some embodiments, one or more components of system 100 (e.g., medical imaging device 110, processing device 120, storage device 130, terminal 140) can send data and / or information to other components via network 150. Network 150 can be any one or more of a wired or wireless network.

[0042] It should be noted that the above description is provided for illustrative purposes only and is not intended to limit the scope of this specification. Various changes and modifications can be made by those skilled in the art based on the content of this specification. Features, structures, methods, and other features of the exemplary embodiments described herein can be combined in various ways to obtain other and / or alternative exemplary embodiments. For example, the processing device 120 may be based on a cloud computing platform, such as a public cloud, private cloud, community cloud, and hybrid cloud. However, these changes and modifications will not depart from the scope of this specification.

[0043] Figure 2 This is a schematic diagram of an exemplary reference detector for CT scanning, shown according to some embodiments of this specification. Figure 2 As shown, the reference detector 200 includes a reference detector body 210 and a filter plate 220. The reference detector 210 includes a detector pixel array 211 and a signal readout component 212.

[0044] The reference detector body 210 is used to receive and measure radiation emitted from a radiation source (e.g., an X-ray source). Figures 3A-3E This is a schematic diagram of the structure of an exemplary reference detector for CT scanning, shown according to some embodiments of this specification. Figure 3A As shown, the reference detector 300 includes a reference detector body 310, which includes a scintillator array 311. The reference detector body 310 has two opposing surfaces, one of which is a radiation receiving surface (e.g., X-rays, etc.), i.e., the surface facing the radiation.

[0045] The detector pixel array 211 is a detection component for receiving radiation. The detector pixel array comprises multiple detector pixels arranged in an array, where each detector pixel is a detection unit. The detector pixels are either scintillator pixels (i.e., scintillator detectors) or semiconductor pixels (i.e., semiconductor detectors). When the detector pixels are scintillator pixels, the detector pixel array is a scintillator array composed of multiple scintillator pixels, each including a scintillator and a photodiode. The photodiode is used to convert the light signal emitted by the scintillator into an electrical signal. The scintillator is made of a scintillating material, which includes various materials capable of converting X-ray photons into visible light, such as gadolinium oxysulfide (GOS). (This is just an example.) Figure 3A As shown, the scintillator array 311 includes an array 3111 composed of scintillators and an array 3112 composed of photodiodes. When the detector pixel is a semiconductor pixel, the detector pixel includes semiconductor pixels, and the detector pixel array is a semiconductor array composed of multiple semiconductor pixels. The semiconductor pixels are made of semiconductor materials, such as cadmium telluride, cadmium zinc telluride, or silicon. This specification will use scintillator pixels and scintillator arrays as examples for the following descriptions. The detector pixel array can include various forms of arrays, such as 4×5, 6×6, 8×8, etc., detector pixel arrays. This is only an example. Figure 3B As shown, the scintillator array 311 comprises a 3×3 array of scintillator pixels, where one scintillator pixel is scintillator pixel 311-1, and each scintillator pixel is a square with a side length of 1 mm. As another example, as... Figure 3E As shown, the scintillator array 311 includes an array of 4×5 scintillator pixels.

[0046] In some embodiments, the number of detector pixels in the detector pixel array 211 is 20-80. In some embodiments, the number of detector pixels in the detector pixel array 211 is 25-75. In some embodiments, the number of detector pixels in the detector pixel array 211 is 30-70. In some embodiments, the number of detector pixels in the detector pixel array 211 is 35-65. In some embodiments, the number of detector pixels in the detector pixel array 211 is 40-60. In some embodiments, the number of detector pixels in the detector pixel array 211 is 45-55. In some embodiments, the number of detector pixels in the detector pixel array 211 is 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, etc. By setting the number of detector pixels to 20-80, redundant design of detector pixels can be achieved. Even if a few micro-elements degrade in performance or fail completely due to aging or damage, the system can still calculate a reliable reference value from the remaining large number of normal pixels using statistical methods (e.g., outlier removal). Simultaneously, the total area of ​​the detector pixel array can be controlled, ensuring performance while controlling cost, and also enabling miniaturization of the detector body. In some embodiments, the number of detector pixels in the detector pixel array 211 can also be other numbers, such as 9, 90, 100, etc.

[0047] The signal readout component 212 is used to process and output the electrical signals of the detector pixels. The signal readout component includes a dedicated readout circuit and a data acquisition board. The dedicated readout circuit is used to read out the electrical signals; for example, the dedicated readout circuit may include one or any combination of an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a programmable logic controller (PLC), etc. The data acquisition board is used to acquire the readout data. In some embodiments, the signal readout component may also include other components, such as a data transmission component. For example, such as... Figure 3A As shown, the reference detector body 310 also includes a signal readout component 312, which includes a dedicated readout circuit 3121 and a data acquisition board 3122. The data acquired by the data acquisition board 3122 is transmitted to a processing device (e.g., processing device 120) for processing via a data transmission line. By including components such as the dedicated readout circuit and the data acquisition board, it is possible to ensure that after the detector pixels convert the optical signal into an electrical signal, they can further convert it into a data format that is easy to process.

[0048] The filter plate 220 is used to physically attenuate and filter incident X-rays. The filter plate 220 is located on the side of the detector pixel array 212 closest to the CT tube, i.e., on the receiving surface side of the reference detector body 210. For example, as... Figure 3D and Figure 3EAs shown, the filter plate 320 is located on the side of the scintillator array 311 in the reference detector body 310 near the CT tube, that is, on the upper side of the X-ray receiving surface of the reference detector body 310. After being filtered by the filter plate 320, the X-rays reach the scintillator array 311. The material of the filter plate 320 includes high-density and / or high atomic number metals, such as tungsten, titanium, or tungsten-nickel-iron alloys, which are used to attenuate the intensity of radiation received by the detector pixels.

[0049] The filter plate 220 includes multiple sub-regions and multiple through-holes, which allow X-rays to pass through and be received by detector pixels. A sub-region is a plurality of independent, functional local areas divided on the filter plate. Each sub-region faces one of the multiple detector pixels along a first direction. Specifically, there is a one-to-one correspondence between sub-regions and detector pixels, and the projection of each sub-region in the first direction at least partially or completely covers the corresponding detector pixel below it. Each sub-region has at least one through-hole, the first direction being the incident direction of the radiation, which is perpendicular to the surface of the filter plate 220, i.e., along the thickness direction of the filter plate 220. For example, as... Figure 3D As shown, the first direction is the direction of X-ray illumination, i.e., the direction of the arrow. It's understandable that radiation is directly received by the detector pixels through the aperture, while in areas without apertures, the radiation is blocked by a filter plate, causing attenuation. For example, as... Figure 3B As shown, the filter plate 320 in the reference detector 300 includes nine sub-regions, each with a through-hole. The through-hole in the sub-region corresponding to the scintillator pixel 311-1 is a through-hole 321, allowing radiation to be directly received by the scintillator pixel 311-1 through the through-hole 321. For example, as... Figure 3E As shown, the filter plate 320 in the reference detector 300 includes 20 sub-regions, each with a through-hole. Radiation can pass through these through-holes and be directly received by the scintillator pixels in the scintillator array 311, while radiation outside the through-holes is blocked and reflected. In some embodiments, the through-hole sizes of different sub-regions can be the same or different, and the through-hole sizes can be adjusted. By opening through-holes, dose attenuation and gating of X-rays are achieved; by making a one-to-one correspondence between sub-regions and detector pixels, crosstalk is avoided, ensuring the independence and accuracy of the signal of each detection unit; at the same time, fine-tuning the through-hole sizes of different sub-regions can adapt to small differences in local dose distribution, achieving more precise dose control.

[0050] Because the filter plate 220 has through holes, there is no need for complex blocking and scattering mechanisms. The thickness of the filter plate 220 can be less than or equal to a preset value, which can be set as needed to prevent detector pixels from saturating. In some embodiments, the preset value is 2-3 mm. For example, the filter plate 210 can be a tungsten plate with a thickness of 2-3 mm.

[0051] The total area of ​​the through holes on each sub-region of the filter plate 220 is the same. For example, as Figure 3C As shown, the area of ​​the through holes in each sub-region of the filter plate 220 is the same. It is understood that if the area of ​​the through holes is the same, the dose attenuation effect produced in each sub-region of the filter plate will be the same. By making the total area of ​​the through holes in each sub-region of the filter plate 220 the same, it is possible to ensure that each sub-region produces the same dose attenuation effect; at the same time, it simplifies signal processing and calculation, reduces manufacturing costs and complexity, and improves product consistency. In some embodiments, the total area of ​​the through holes in each sub-region of the filter plate 220 may be different.

[0052] In some embodiments, each sub-region has a single via, and the detector pixels correspond one-to-one with the via. For example, as... Figure 3C and Figure 3E As shown, each sub-region of the filter plate 320 has a single through-hole. This eliminates the internal structural complexity that might result from multiple through-holes within a sub-region, simplifying manufacturing and quality control. When each sub-region has a single through-hole, the single through-hole may be directly opposite to or not directly opposite the geometric center of the detector pixel; that is, the projection of the single through-hole in the first direction may be centered on the geometric center of the detector pixel, resulting in geometric symmetry or asymmetry. In some embodiments, each sub-region may have multiple through-holes, such as 2, 3, 4, etc.

[0053] Through-holes can have various cross-sectional shapes, such as circular, square, hexagonal, and irregular shapes. The equivalent diameter of each through-hole is a preset diameter. The equivalent diameter is used to uniformly measure the hole size. When the through-hole cross-section is circular, the equivalent diameter is the actual diameter; when the through-hole cross-section is square, hexagonal, or other shapes, the equivalent diameter is the diameter of a circle with the same area as the opening. For example, as... Figure 3C As shown, the through-hole 321 is square with a side length of 100μm, and its equivalent diameter is... μm. Understandably, the area of ​​a single via cannot be greater than or equal to the area of ​​a single sub-region. If the area of ​​a single via is too large, it cannot provide sufficient attenuation, resulting in excessively high X-ray intensity reaching the detector pixel, potentially saturating the detector or photodiode and failing to attenuate the light intensity. If the area of ​​a single via is too small, the photon flux reaching the detector pixel is too low, resulting in a weak light signal. This weak signal is easily masked by the background noise of the detector and readout circuit, leading to a low signal-to-noise ratio and affecting measurement accuracy. In some embodiments, the equivalent diameter ranges from 100 μm to 200 μm. In some embodiments, the equivalent diameter ranges from 110 μm to 190 μm. In some embodiments, the equivalent diameter ranges from 120 μm to 180 μm. In some embodiments, the equivalent diameter ranges from 130 μm to 170 μm. In some embodiments, the equivalent diameter ranges from 140 μm to 160 μm. In some embodiments, the equivalent diameter is 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, 2000μm, etc. By setting the equivalent diameter of each via to 100μm~200μm, an optimized balance between dose attenuation and signal quality is achieved. In some embodiments, the equivalent diameter can be other values, such as 80μm, 210μm, etc.

[0054] The filter plate 220 is fixedly connected to the detector pixel array 210, meaning that the filter plate and the detector pixel array are physically combined into a single component, for example, through bonding or mechanical fixation. In some embodiments, the filter plate 220 and the detector pixel array 210 are bonded using an adhesive (e.g., optical adhesive, structural adhesive, etc.), that is, the back side of the filter plate 220 (i.e., the side closest to the detector pixel array) is directly bonded and fixed to the front side of the detector pixel array (i.e., the photosensitive surface that receives X-rays). This allows for almost no gap between the filter plate and the detector pixel array, forming a compact detection unit, thereby minimizing the air gap between the filter plate and the detector pixels, effectively reducing X-ray scattering in this area, and thus reducing signal crosstalk between adjacent detector pixels. In some embodiments, the filter plate 220 and the detector pixel array 210 are fixed together using mechanical structures (e.g., screws, clips, etc.). By fixing the filter plate 220 and the detector pixel array 210 together, long-term stable alignment between the through-hole and the detector pixels can be ensured, thereby guaranteeing the accuracy and reliability of dose measurement.

[0055] In some embodiments, the reference detector 200 further includes a support member 230. The support member 230 provides physical support and positioning for the filter plate and the detector pixel array. The support member 230 is disposed between the filter plate 220 and the reference detector body 210, such that a gap is formed between the filter plate 220 and the detector pixels. The support member 230 is a detachable structure. For example, the support member 230 may include a frame, a housing, a base, a mounting plate, or any other structural component with a specific shape and rigidity. The material of the support member 230 may include metal, high-strength engineering plastics, etc. The filter plate 220 and the detector pixel array 210 are respectively connected to the support member 230. There is a gap between the filter plate 220 and the multiple detector pixels, that is, the filter plate 220 and the detector pixel array 211 are each independently fixed to the same support member 230, and there is physical space or distance between the filter plate 220 and the detector pixel array 211; they do not directly contact each other. The gap between the filter plate 220 and multiple detector pixels allows for the establishment of a thermal isolation zone between the filter plate 220 and the more temperature-sensitive photodiode and readout circuit, preventing detector performance drift due to temperature rise and improving heat dissipation. The filter plate and detector pixel array (especially brittle scintillation crystals) may have different coefficients of thermal expansion, and the gap allows them to expand and contract independently, avoiding the accumulation of thermal stress and isolating stress, thereby improving the product's environmental adaptability and reliability.

[0056] The size of the gap between the filter plate 220 and the plurality of detector pixels is less than or equal to a preset gap. In some embodiments, the preset gap is 5 mm. By making the gap between the filter plate 220 and the detector pixel array 211 less than or equal to the preset gap, excessive scattered X-rays can be prevented from entering non-corresponding detector pixels, causing signal crosstalk. In some embodiments, the preset gap can be other values, such as 1 mm, 0.5 mm, etc.

[0057] The total thickness of the reference detector 200 along a first direction is less than or equal to a preset thickness, where the first direction is the incident direction of the radiation. In some embodiments, the preset thickness is 10 mm, 9 mm, 8 mm, 7 mm, 6 mm, 5 mm, 4 mm, 3 mm, etc. As an example only, the filter plate 210 can be a tungsten plate with a thickness of 2-3 mm, and the detector pixel array 211 can be 1-2 mm thick, such that the total thickness of the reference detector 200 along the first direction is less than or equal to 10 mm. In some embodiments, the preset thickness can be other values, such as 11 mm, 12 mm, etc. By reducing the thickness of the reference detector 200, the volume and weight of the reference detector are reduced (e.g., a thickness less than or equal to 10 mm results in a weight of several hundred grams), improving installation flexibility and ease of maintenance.

[0058] In some embodiments of this specification, through holes are provided on the filter plate, and the light transmission area is controlled to achieve precise dose attenuation; by making the position of each sub-region on the filter plate correspond one-to-one with the detector pixel, signal interference is avoided and the signal processing and calibration process is simplified; by controlling the thickness of the filter plate, the area of ​​the through holes, and the size of the detector pixel array, the reference detector is miniaturized, thereby improving installation flexibility.

[0059] Figure 4 These are schematic diagrams of exemplary CT imaging apparatuses according to some embodiments of this specification. Figure 4 As shown, the CT imaging device 400 includes a reference detector 200, an X-ray tube 420, a collimator 430, a main detector 440, and a gantry 450. The main detector 440 includes a detector pixel array 441.

[0060] Reference detector 200 is used in CT scanning equipment to monitor changes in X-ray dose and energy in real time. Its signal is used to correct response drift of the main detector 440, ensuring image reconstruction quality. For example, reference detector 200 may include reference detector 1020. For more information on reference detector 200, see [link to relevant documentation]. Figure 2 .

[0061] The X-ray tube 420 is used to generate radiation, namely X-rays. The X-ray tube 420 is housed within the gantry 450. The X-ray tube 420 generates X-rays for scanning by applying a high voltage to cause electrons to bombard a metal target. For example, the X-ray tube 420 may include X-ray tube 1010.

[0062] Collimator 430 is used to shape the conical X-ray beam generated by the X-ray tube 420 into a desired fan-shaped or conical beam and to limit unwanted scattered radiation. Collimator 430 is positioned between the X-ray tube 420 and the main detector 440 to reduce radiation scattering. In some embodiments, collimator 420 is a mechanical structure made of a high-density material (e.g., tungsten) located in front of the X-ray exit of the X-ray tube 420.

[0063] The main detector 440 is used in an imaging device to receive X-rays that have passed through the scanned object and convert them into electrical signals. For example, the main detector 440 may include a CT detector 1040. The main detector is disposed within a gantry 450 and opposite to the X-ray tube 420 for receiving radiation that has passed through the scanned object. The main detector is also referred to as a detector system. The main detector 440 includes a detector pixel array consisting of multiple detector pixels to acquire projection data required for image reconstruction. The detector pixels in the main detector are scintillator pixels or semiconductor pixels.

[0064] Currently, the reference detector needs to be located close to the X-ray tube, so it is usually installed inside the collimator, occupying a large space, making installation difficult, and limiting installation flexibility due to the limited internal space of the collimator. For example, Figure 5 This is a schematic diagram illustrating exemplary reference detector mounting positions according to some embodiments of this specification. For example... Figure 5 As shown, the reference detector 510 is installed inside the collimator 530 near the X-ray tube 520. The X-ray source is located at the focal point of the X-ray tube 520. After being filtered by the filter 531 installed in the collimator 530, the X-rays irradiate the patient 550 and are then received by the main detector 540. It can be seen that due to the limited internal space of the collimator 530 containing components such as the filter 531, the available installation positions for the reference detector 550 are very limited.

[0065] In some embodiments, a reference detector 200 is disposed between the X-ray tube 420 and the main detector 440 to receive at least a portion of the radiation that does not penetrate the scanned object (e.g., a human body, a phantom, etc.). For example, the reference detector 200 may be disposed between the collimator 430 and the main detector 440, or between the X-ray tube 420 and the collimator 430.

[0066] In some embodiments, a reference detector 200 is disposed between the main detector 440 and the collimator 430. For example, Figure 6 This is a schematic diagram illustrating exemplary reference detector mounting positions according to some embodiments of this specification. For example... Figure 6 The CT imaging device shown can be implemented as a CT imaging device 400, with collimator 610, X-ray tube 620, reference detector 630, and main detector 640 corresponding to reference detector 200, X-ray tube 420, collimator 430, and main detector 440, respectively. Due to the small size of the reference detector 610, it is positioned between the main detector 640 and the collimator 630. X-rays are filtered by filter 631 installed in the collimator 630 and then received by the reference detector 610, simultaneously irradiating the patient 650, before being received by the main detector 640. By positioning the reference detector 200 between the main detector 440 and the collimator 430, the installation position is more flexible. In some embodiments, the reference detector 200 can also be positioned in other locations, for example, with... Figure 5 Similarly, the reference detector 200 can be positioned inside the collimator 430 near the X-ray tube 420.

[0067] The reference detector 200 is connected to the side of the collimator 430 facing the main detector 440. For example, as Figure 6As shown, the reference detector 610 can be connected to the side of the collimator 630 facing the main detector 640. In some embodiments, the reference detector 200 is attached to the outer surface of the collimator 430 facing the main detector 440, or mounted on a support structure close to that surface, for example, by means of screws, clips, adhesives, etc. The reference detector measures the intensity of the X-ray beam that is about to penetrate the patient. By connecting the reference detector 200 to the side of the collimator 430 facing the main detector 440, the position of the reference detector 200 is as close to the patient as possible. The reference signal acquired by the reference detector 200 directly reflects the actual radiation dose used for imaging, avoiding radiation components that might be included when measuring closer to the X-ray tube and subsequently blocked by the collimator 430. This results in a higher correlation between the reference signal and the signal acquired by the main detector 440, and higher correction accuracy. At the same time, since the reference detector 200 is mounted outside the collimator 430, maintainability is improved.

[0068] In some embodiments, a reference detector 200 is disposed between the X-ray tube 420 and the collimator 430. For example, as Figure 9 As shown, the reference detector is located between the X-ray tube and the collimator, and the rays emitted from the focal point of the CT X-ray tube are directly received by the reference detector.

[0069] As mentioned above, the filter plate of the reference detector 200 includes multiple sub-regions, each of which has at least one through-hole. The total area of ​​the through-holes in each sub-region is shown in formula (1): (1), Wherein, S1 is the total area of ​​the through holes in each sub-region of the filter plate of the reference detector 200; S2 is the pixel area of ​​each detector pixel (e.g., scintillator pixel, semiconductor pixel) on the main detector 440, and S2 is a constant (one of the parameters of the reference detector 200) determined according to the detector pixels; L1 is the distance from the focal point of the X-ray tube 420 (i.e., the source point of X-ray generation) to the detector pixel array (e.g., scintillator array, semiconductor array) of the reference detector 200 (i.e., the effective plane of signal conversion), and L1 is obtained by measurement; L2 is the distance from the focal point of the X-ray tube 420 to the detector pixel array of the main detector 440, and L2 is a constant (one of the parameters of the reference detector 200), which can also be obtained by measurement. By using precisely measured or fixed distances of L1 and L2, and the known fixed parameter S2 of the main detector 440, the total area of ​​the through holes in each sub-region of the filter plate can be calculated by formula (1). Based on the obtained total area of ​​the through holes, the radiation dose can be converted, so that the measurement result of the reference detector 200 is directly equivalent to the measurement value of the position of the main detector at the physical level, thus ensuring the accuracy of image correction.

[0070] The gantry 450 is used to support other components in the CT imaging apparatus 400, such as at least one of the reference detector 200, X-ray tube 420, collimator 430, and main detector 440. The gantry 450 is rotatable and includes a central scanning aperture (also called a scanning cavity) for accommodating the object being scanned. The gantry 450 is annular or similar in shape.

[0071] Figure 7 This is a flowchart illustrating a method for manufacturing an exemplary CT imaging apparatus according to some embodiments of this specification. For example... Figure 7 As shown, process 300 includes the following steps. In some embodiments, processing device 120 can manufacture a CT imaging device, such as medical imaging device 110 or CT imaging device 400, by performing at least some of the steps in process 300. This specification will now describe the manufacture of CT imaging device 400 as an example.

[0072] Step S710: Determine the installation location of the reference detector.

[0073] The processing device 120 determines the spatial position of the reference detector within the CT imaging device (e.g., CT imaging device 400) based on parameters such as the size of the reference detector (e.g., reference detector 200). For example, it may be installed on the outside of the collimator (e.g., collimator 430) towards the main detector (e.g., main detector 440). In some embodiments, the processing device 120 may also determine the installation position of the reference detector in other ways, such as according to the design drawings of the CT imaging device.

[0074] Step S720: Determine the structural parameters of multiple through holes based on the installation location.

[0075] The main detector includes a detector pixel array, which comprises multiple detector pixels, wherein the detector pixels in the main detector are scintillator pixels or semiconductor pixels. The filter plate of the reference detector (e.g., filter plate 220) includes multiple sub-regions, each sub-region having at least one through-hole. The structural parameters of the through-hole are parameters representing the size and location of the through-hole, and include multiple parameters. These structural parameters include L1, L2, S1, and S2, etc. L1 is the distance from the focal point of the X-ray tube of the CT imaging device (e.g., X-ray tube 420) to the detector pixel array of the reference detector (e.g., detector pixel array 211). L2 is the distance from the focal point of the X-ray tube of the CT imaging device to the detector pixel array of the main detector. S1 is the total area of ​​the through-holes in each sub-region of the filter plate. S2 is the pixel area of ​​each detector pixel on the main detector. In some embodiments, the through-hole structural parameters also include other parameters, such as the shape (e.g., square hole, round hole, etc.) and number of through-holes.

[0076] The processing device 120 determines the structural parameters of the through-hole by: determining L2 and S2, determining L1 based on the installation position, and determining S1 based on L1, L2, and S2. L2 and S2 are parameters of the CT imaging device, and the processing device 120 obtains L2 and S2 by acquiring the parameters of the CT imaging device. The processing device 120 can also obtain L2 by measurement using a measuring device (e.g., a laser rangefinder). Based on the installation position of the reference detector, the processing device 120 measures or calculates (e.g., using the design drawings of the CT imaging device) the distance L1 from the X-ray tube focal point to the reference detector. The processing device 120 inputs L1, L2, and S2 into formula (1) to obtain S1.

[0077] Step S730: Fabricate a reference detector based on structural parameters.

[0078] The processing device 120 processes a filter plate according to structural parameters using processing equipment (e.g., CNC machine tools, machining centers, robotic arms, etc.), assembles the reference detector body, and connects the filter plate to the reference detector body. For example, the processing device 120 uses materials such as tungsten to create through-holes with structural parameters through precision machining (e.g., laser drilling). Alternatively, the processing device 120 integrates a scintillator, photodiode, dedicated readout circuit, and data acquisition board using machine assembly. Or, the processing device 120 uses bonding or mechanical fixing to orient the filter plate toward the X-ray tube focal point, ensuring precise alignment of the through-holes with the detector pixels to form a complete reference detector. In some embodiments, the processing device 120 can display the structural parameters, allowing technicians to manually fabricate the reference detector based on these parameters.

[0079] Step S740: Install the prepared reference detector at the installation location.

[0080] The processing device 120 fixes the prepared reference detector in the installation position by means of bonding or mechanical fixing (e.g., screws, riveting, etc.) (e.g., by a robotic arm). In some embodiments, the prepared reference detector can be installed in the installation position manually.

[0081] In some embodiments of this specification, the core structural parameters (L1, L2, S1, and S2) of the reference detector are actively customized according to the installation position of the reference detector, thereby ensuring the accuracy of the reference signal; and the installation position of the reference detector is flexible and adjustable, which can adapt to the layout scheme of various imaging devices and improve the design flexibility of the imaging device.

[0082] It should be noted that the above description of process 700 is for illustrative purposes only and does not limit the scope of this specification. Those skilled in the art can make various modifications and changes to process 700 under the guidance of this specification. However, these modifications and changes are still within the scope of this specification. For example, after the main detector has been calibrated due to factors such as usage time, the installation position of the reference detector can be adjusted according to the parameters of the calibrated main detector.

[0083] Figure 10 These are schematic diagrams of exemplary CT scanning systems according to some embodiments of this specification. Figure 10 As shown, system 1000 includes an X-ray tube 1010, a reference detector 1020, a gantry 1030, a CT detector 1040, a data acquisition system 1050, and a processing device 1060. In some embodiments, at least one of the medical imaging device 110 and the CT imaging device 400 is implemented by system 1000.

[0084] The X-ray tube 1010 is housed within the gantry 1030 and is used to generate radiation, i.e., X-rays. A reference detector 1020 is positioned between the X-ray tube 1010 and the CT detector 1040 to receive at least a portion of the radiation that has not passed through the patient and to monitor changes in X-ray dose and energy in real time. Its signal is used to correct response drift of the CT detector 1040 (i.e., the main detector) to ensure image reconstruction quality. The gantry 1030 is used to support other components in the system 1000 (e.g., the X-ray tube 1010, the reference detector 1020, the CT detector 1040, and the data acquisition system 1050). The gantry 1030 is annular and rotatable, with a central scanning aperture for accommodating the patient. The CT detector 1040, the main detector in the system 1000, is housed within the gantry 1030 and positioned opposite the X-ray tube 1010. It receives the X-rays that have passed through the patient and converts them into electrical signals. Data acquisition system 1050 is used to collect data (electrical signals) acquired by detectors (e.g., at least one of reference detector 1020 and CT detector 1040) and transmit them to processing device 1060. Processing device 1060 is used to process the data acquired by the detectors, such as at least one of the data acquired by reference detector 1020 and CT detector 1040. Processing device 1060 is a device including a processor and memory, such as processing device 120.

[0085] like Figure 10As shown, the X-ray tube 1010, reference detector 1020, CT detector 1040, and data acquisition system are all housed within the gantry 1030, with the patient positioned within the scanning aperture at the center of the annular gantry 1030. The reference detector 1020 is positioned between the patient and the X-ray tube 1010, near the outer side of the tube. X-rays emitted from the X-ray tube 1010 directly irradiate the patient, while X-rays from the side of the tube 1010 are received by the reference detector 1020, and X-rays passing through the patient are received by the CT detector 1040. Data acquired by at least one of the reference detector 1020 and the CT detector 1040 is collected by the data acquisition system 1050 and then sent to the processing device 1060 for processing.

[0086] The basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this specification. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this specification. Such modifications, improvements, and corrections are suggested in this specification and therefore remain within the spirit and scope of the exemplary embodiments described herein.

[0087] Furthermore, this specification uses specific terms to describe embodiments thereof. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of this specification. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Moreover, certain features, structures, or characteristics in one or more embodiments of this specification can be appropriately combined.

[0088] Furthermore, unless expressly stated in the claims, the order of processing elements and sequences, the use of numbers and letters, or other names described in this specification are not intended to limit the order of the processes and methods described herein. Although various examples have been discussed in the foregoing disclosure of some embodiments of the invention that are currently considered useful, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments; rather, the claims are intended to cover all modifications and equivalent combinations that conform to the spirit and scope of the embodiments described herein. For example, while the system components described above can be implemented using hardware devices, they can also be implemented solely using software solutions, such as installing the described system on existing servers or mobile devices.

[0089] Similarly, it should be noted that, in order to simplify the description disclosed herein and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of embodiments in this specification may sometimes combine multiple features into a single embodiment, drawing, or description thereof. However, this method of disclosure does not imply that the subject matter of this specification requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of a single embodiment disclosed above.

[0090] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples with the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of range in some embodiments of this specification are approximate values, in specific embodiments, such values ​​are set as precisely as feasible.

[0091] For each patent, patent application, patent application publication, and other material such as articles, books, specifications, publications, and documents referenced in this specification, the entire contents of which are incorporated herein by reference. This excludes historical application documents that are inconsistent with or conflict with the content of this specification, as well as documents that limit the broadest scope of the claims in this specification (currently or subsequently appended to this specification). It should be noted that in the event of any inconsistency or conflict between the descriptions, definitions, and / or terminology used in the supplementary materials to this specification and the content of this specification, the descriptions, definitions, and / or terminology used in this specification shall prevail.

[0092] Finally, it should be understood that the embodiments described in this specification are merely illustrative of the principles of the embodiments described herein. Other variations may also fall within the scope of this specification. Therefore, alternative configurations of the embodiments described herein are intended to be illustrative rather than limiting, and should be considered consistent with the teachings of this specification. Accordingly, the embodiments described herein are not limited to those explicitly introduced and described herein.

Claims

1. A reference detector for CT scanning, characterized in that, include: The reference detector body includes a detector pixel array, which is an array composed of multiple detector pixels. The detector pixels are scintillator pixels or semiconductor pixels. The scintillator pixels include a scintillator and a photodiode. The reference detector body has two opposing surfaces, one of which is a radiation receiving surface. and A filter plate is disposed on one side of the receiving surface of the reference detector body. The filter plate has multiple through holes, wherein when the radiation irradiates the reference detector, the radiation reaches the multiple detector pixels through the multiple through holes.

2. The reference detector as claimed in claim 1, characterized in that, Each detector pixel corresponds to one of the through holes.

3. The reference detector as claimed in claim 1, characterized in that, The semiconductor pixels are made of cadmium zinc telluride, cadmium telluride, or silicon.

4. The reference detector as claimed in claim 1, characterized in that, The reference detector body also includes a signal readout component, which includes a dedicated readout circuit and a data acquisition board.

5. The reference detector as claimed in claim 4, characterized in that, A support member is provided between the filter plate and the reference detector body to form a gap between the filter plate and the detector pixel.

6. A CT imaging device, characterized in that, include: The frame is rotatable; An X-ray tube, housed within the frame, is used to generate radiation; The main detector, housed within the frame and positioned opposite the X-ray tube, is used to receive the radiation after it has passed through the scanned object. A collimator, positioned between the X-ray tube and the main detector, is used to reduce the scattering of the radiation. and A reference detector, disposed between the X-ray tube and the main detector, is used to receive at least a portion of the radiation that has not penetrated the scanned object; The reference detector includes a filter plate and a plurality of detector pixels. The filter plate has at least one through hole that allows the radiation to pass through and be received by the detector pixels.

7. The CT imaging device as described in claim 6, characterized in that, The filter plate is made of tungsten or titanium.

8. The CT imaging device as described in claim 6, characterized in that, There are multiple through holes, and each detector pixel corresponds to one through hole. The reference detector body includes detector pixels and a signal readout component. The signal readout component includes a dedicated readout circuit and a data acquisition board.

9. A CT imaging device, characterized in that, include: The frame is rotatable; An X-ray tube, housed within the frame, is used to generate radiation; The main detector, housed within the frame and positioned opposite the X-ray tube, is used to receive the radiation after it has passed through the scanned object. A collimator, positioned between the X-ray tube and the main detector, is used to reduce the scattering of the radiation. and A reference detector, disposed between the collimator and the main detector, is used to receive at least a portion of the radiation that has not penetrated the scanned object; The reference detector includes a filter plate and a plurality of detector pixels. The filter plate has at least one through hole that allows the radiation to pass through and be received by the detector pixels.

10. A CT imaging device, characterized in that, include: The frame is rotatable; An X-ray tube, housed within the frame, is used to generate radiation; The main detector, housed within the frame and positioned opposite the X-ray tube, is used to receive the radiation after it has passed through the scanned object. A collimator, positioned between the X-ray tube and the main detector, is used to reduce the scattering of the radiation. and A reference detector, disposed between the X-ray tube and the main detector, or disposed between the collimator and the main detector, is used to receive at least a portion of the radiation that has not penetrated the scanned object; The reference detector includes multiple detector pixels, and a high-density and / or high atomic number material is disposed on one side of the receiving surface of the reference detector body. The high-density and / or high atomic number material is used to reduce the intensity of the radiation received by the detector pixels.

Images