Channel type X-ray linear array target assembly, CT bulb tube and CT equipment

Abstract

The invention relates to a channel type X-ray linear array target assembly, a CT bulb tube and CT equipment. The target assembly comprises a plurality of target discs and a target disc shaft, the target discs are sequentially installed on the target disc shaft, annular target bodies are arranged on the edge portions of the target discs, and except for the target disc located on the foremost side, gaps used for forming electron beam channels leading to the target disc are formed in any target disc and the target disc located in front of the target disc. The electron beam channels are aligned with the target surfaces on the corresponding target discs, and the electron beam channels leading to the target discs are sequentially arranged in the circumferential direction. The target assembly and an electron gun used for generating electron beams are arranged in a shell of the CT bulb tube. The CT equipment adopts the CT bulb tube. The detection speed can be improved, and the service life of equipment can be prolonged.

Description

Technical Field

[0001] This invention relates to a channel-type X-ray linear array target assembly, a CT tube, and CT equipment, belonging to the field of medical equipment technology. Background Technology

[0002] An X-ray tube (CT tube) mainly consists of a cathode, an anode, and a glass or metal-ceramic outer shell. The cathode contains a filament and a focusing cup. The filament heats up when energized and emits electrons, while the focusing cup focuses the electron beam. The anode is usually a rotating anode, consisting of a target disk and a drive motor that rotates the target disk shaft. The target disk is usually made of high-temperature resistant materials such as tungsten-rhenium alloy and has a target surface that generates an X-ray beam under electron beam bombardment. The outer shell is used to ensure an internal vacuum environment to facilitate the free acceleration of electrons, while also providing heat insulation and electrical insulation. Its main working principle and process are as follows: the filament is heated to a high temperature, releasing thermionic electrons. Under the action of the high-voltage electric field between the anode and cathode, the electrons accelerate towards the anode target disk. The high-speed electrons collide with the target disk, and some of their kinetic energy is converted into X-rays. Through the appropriate angle (taper) design of the target surface, the X-ray beam passes through the X-ray transmission window (referred to as the window) on the shell in a direction perpendicular to the axis of the target disk (or radial direction) to perform CT detection. However, although the rotating anode design can continuously change the impact position of the electron beam on the target disk, which helps to avoid excessive heat concentration in the target disk, the target disk is still prone to performance degradation or even damage due to overheating during high-power, long-term scanning, such as whole-body vascular imaging and multi-site combined scanning, which limits scanning throughput and efficiency. Therefore, how to improve efficiency while avoiding target disk overheating as much as possible has become a key technical problem that urgently needs to be solved. For example, Chinese patent document CN117517358A discloses a CT scanning system, including: a transport device for moving the scanned object in a scanning channel along a predetermined transport direction; p scan segments, each scan segment including a distributed X-ray source and a detector array, the p scan segments being arranged at intervals along the transport direction, where p is a positive integer greater than or equal to 2; in each scan segment, the distributed X-ray source including m target points, the m target points being configured to be activated in a predetermined order to emit X-ray beams, where m is a positive integer greater than or equal to 2; a detector array for detecting X-rays emitted from the distributed X-ray source and passing through the scanned object, and generating projection data based on the detected X-rays; and an image reconstruction device configured to generate a computed tomographic image of the scanned object based on the projection data detected by each detector in the p scan segments. For example, Chinese patent document CN119438258A discloses a CT imaging system based on a distributed micro-focus X-ray source. It includes a distributed X-ray source with multiple micro-focuses, a detector, a scanning carrier, a control module, and a data processing module. During the scanning process, the distributed X-ray source and the detector rotate simultaneously around the rotation center relative to the object to be detected. The multiple micro-focuses emit beams sequentially according to the beam emission strategy to disperse heat dissipation, which can effectively improve the peak power of the micro-focus X-ray source and reduce the time required for a single CT scan. By designing the beam emission strategy of the distributed X-ray source, the sampling distribution of multiple micro-focuses can be optimized to achieve sub-pixel-level image reconstruction and further improve spatial resolution.Chinese patent document CN120419986A discloses a multi-segment linear X-ray source static real-time CT imaging system, which includes a scanning device and a radiation source control unit. The scanning device is equipped with a multi-segment X-ray source array and a detector. The emitting end of the multi-segment X-ray source array faces the detector, and the multi-segment X-ray source array is connected to the radiation source control unit. These existing technologies each have their own characteristics and are suitable for their respective applications, but they still have certain limitations. For example, the scanning speed is limited: due to the physical limits of the mechanical rotating parts, the rotation speed of the rotating anode tube is difficult to increase significantly, and the single-turn scanning time is difficult to break through 0.2 seconds. When imaging dynamic organs (such as the heart), motion artifacts are easily generated due to organ movement, affecting the imaging accuracy and hindering the accurate detection of early small lesions. The bearing life is short: the high-speed rotating anode requires high-performance bearings for support. However, traditional ball bearings wear out rapidly when working in high-temperature (>500℃) and high-speed environments, with an average life of only 30,000-50,000 hours. Frequent bearing replacement increases equipment maintenance costs and downtime, reducing equipment efficiency. Summary of the Invention

[0003] The purpose of this invention is to improve detection speed and extend the service life of CT tubes.

[0004] The technical solution of this invention is: a channel-type X-ray linear array target assembly, including target disks and target disk shafts. Multiple target disks are sequentially mounted on the target disk shaft, forming a sequential arrangement of target disks along the axial direction. The edge of each target disk has an annular target body (the edge portion capable of supporting / setting the target surface; the position, area, and shape of the target surface on the corresponding target body should meet the requirements of electron beam bombardment). Except for the target disk located at the foremost edge (with the direction closest to the electron gun as the foremost), for any target disk, the target disk in front of it has a notch for forming an electron beam channel leading to that target disk (the size of the notch should meet the requirements for electron beam flow and is usually set on the target body). The electron beam channel is aligned with the target surface (electron beam bombardment area, which can be called the X-ray target, or the effective part of the X-ray target) on the corresponding target disk (or target body), leading to each target. The electron beam channels of the target disk are arranged sequentially in the circumferential direction (either counterclockwise or clockwise). This allows an electron gun to emit an electron beam parallel to the target disk's axis (the electron beam axis is parallel to the target disk's axis). During the rotation of the target assembly, except for the foremost target disk, the electron beam channels of each target disk sequentially pass through the path of the electron beam emitted by the relevant electron gun. The timely emitted electron beams pass through the corresponding electron beam channels (the corresponding notches on the front target disks) and bombard the target surface of the corresponding target disk (target body) (located at the position corresponding to the front electron beam channel). The target surface generates X-rays due to the electron beam bombardment. For the foremost target disk, since there are no other target disks obstructing it, the timely emitted electron beam bombards its target surface when the target surface (the part without notches) passes through the electron beam path, generating X-rays due to the electron beam bombardment.

[0005] Furthermore, when there are multiple notches used to form the same electron beam channel (corresponding to the case of multiple target disks in front), the notches forming the same electron beam channel are aligned with each other, thereby forming a linear electron beam channel parallel to the target disk axis.

[0006] The number of target plates can be determined according to actual needs, but no less than 2.

[0007] The target disk can typically be disc-shaped, or it can be any other suitable shape.

[0008] The base portion of the target disk and its edge ring (with or without notches) can be integrally machined.

[0009] Multiple target disks should work together to maintain the dynamic balance of the target assembly, in order to reduce vibration and wear. When appropriate, individual target disks should also be dynamically balanced.

[0010] Holes can be made in the target disk (including setting it into a spoke structure) and / or a hollow structure can be set in a suitable location to help reduce rotational inertia.

[0011] The target disk can be fixedly connected to the target disk shaft using any suitable existing technology, such as interference fit or flat key connection.

[0012] Preferably, a gap is left between adjacent target disks.

[0013] The spacing between the target disks can be determined according to actual needs.

[0014] Preferably, there are no fewer than two target disks, and the spacing between adjacent target disks is equal. That is, multiple target disks are distributed at equal intervals, thereby forming a linear array of X-rays (sources) to facilitate subsequent data processing. Depending on the actual situation, the spacing between adjacent target disks may also be unequal.

[0015] Furthermore, the electron impact region on the target has a target angle.

[0016] Preferably, the target surface (electron beam bombardment area) of the target body is truncated cone-shaped (the shape of the side of the truncated cone, with or without notches). The corresponding truncated cone is smaller at the front (smaller bottom surface at the front end) and larger at the rear (larger bottom surface at the rear end) with the axis of the target disk as its axis. In this case, the target angle of the target body is determined by the taper of the truncated cone. During the rotation of the target assembly, the angle / target angle between the target surface and the electron beam at the focal point remains unchanged. The size of the truncated cone taper / target angle is set according to actual needs, for example, so that the X-ray beam generated after being bombarded by the electron beam can be emitted radially from the window of the X-ray tube shell.

[0017] Preferably, the target surface (electron beam bombardment area) on the target body is helical, and the target surfaces of each target body are located on the same helical surface (equivalent to a part of this large helical surface).

[0018] Depending on the specific circumstances, the target surface can also be any other suitable shape.

[0019] Furthermore, the number of targets on the same target disk is one; or, the number of targets on the same target disk is multiple, and the multiple targets are distributed on the target disk in an equidistant or unequal interval distribution.

[0020] The CT tube has a housing, inside which is a target assembly and an electron gun for generating an electron beam. The target assembly adopts any of the channel-type X-ray linear array target assemblies disclosed in this invention. The electron beam direction of the electron gun is parallel to the axis of the target disk and faces the target assembly.

[0021] The distance between the electron beam (electron beam axis) and the target disk axis (the distance between the electron beam axis and the target disk axis) is the same as the distance between the target body and the target disk axis (the distance between the preset focal point on the target surface / the intersection of the target surface with the electron beam axis when it is bombarded by the electron beam and the target disk axis). The radial position corresponds to the electron beam channel, so that the electron beam can directly (for the foremost target disk) or pass through the electron beam channel (for target disks other than the foremost target disk) strike the target surface (the preset area on the target body, or X-ray target) of the corresponding target disk. During the rotation of the target assembly (target disk axis), each target body intersects with the electron beam in sequence, and the target surface is bombarded by the electron beam and emits an X-ray beam.

[0022] Furthermore, the interior of the shell is in a certain vacuum state.

[0023] Preferably, the housing is a closed housing, and its cavity is divided into (or includes) a first chamber and a second chamber. The first chamber can accommodate the electron gun and is provided with an electron beam channel that connects to the second chamber. The second chamber can accommodate the target assembly. The high-speed electron beam generated by the electron gun enters the second chamber from the first chamber through the electron beam channel and bombards the target surface blocked in its path.

[0024] Preferably, each target disk has or does not have a helical coil for electron beam focusing adjustment on its front side (front edge). The axial through-hole (central through-hole) of the helical coil is located in the electron beam path, allowing the electron beam to pass through the corresponding helical coil. Based on beam adjustment via the beam adjustment assembly, the high-speed electron beam can be further focused and adjusted by the helical coil located on the front side of each target disk. By applying a corresponding current to the helical coil, the electron beam can be constrained and controlled, ensuring that the focus of the electron beam falls on the target surface of the corresponding target (when the target is rotated into the electron beam path), forming a focal spot of the desired size. The coil on the front side of each target disk can be provided according to actual needs, or it can be omitted if appropriate.

[0025] Preferably, the side wall of the housing is provided with an X-ray window, through which the X-ray beam emitted from the target passes through the window on the vacuum-sealed housing to reach the outside of the X-ray tube, for irradiating the object (including the human body to be detected).

[0026] A CT device is provided with a CT tube for generating an X-ray beam, characterized in that the CT tube is any of the CT tubes disclosed in this invention.

[0027] Preferably, X-ray focus adjustment is performed in the following manner: electron beam focusing is performed by a beam-switching assembly; or, electron beam focusing is performed by a beam-switching assembly, and current is applied to the helical coils in front of each target disk, and the helical coils are further adjusted by controlling the current to form a focus on the target surface located behind it (when the target rotates into the electron beam path), and the focus has the desired size.

[0028] Existing electron beam adjustment methods can be used to adjust the electron beam current using a helical coil, based on the required operating conditions and actual circumstances.

[0029] The beneficial effects of this invention are as follows: since several target disks are set on the target disk axis, and by setting a notch on the front target disk to allow the electron beam to bombard different target disk surfaces in sequence, a time-sequential intermittent working mode of each target body is formed. By having each target disk work in turn to form a linearly moving X-ray beam, the heat load of each target body / target surface is greatly reduced. By reasonably setting the number of target disks, it is possible to control or reduce the temperature rise of the target surface and control or reduce the rotation speed of the target disk axis while increasing the detection speed. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of the X-ray tube involved in this invention; Figure 2 This is a three-dimensional structural schematic diagram of the channel-type X-ray linear array target assembly involved in this invention; Figure 3 This is a three-dimensional structural schematic diagram of the channel-type X-ray linear array target assembly involved in this invention from another angle.

[0031] Labels in the diagram: 100, First chamber; 110, Electron gun; 120, Beam modulation assembly; 130, Electron beam; 200, Second chamber; 210, Target disk; 220, Notch; 230, Target body; 231, Target surface; 240, Target disk shaft; 250, Helical coil; 300, X-ray beam; 400, Housing; 410, Rotor; 420, Bearing; 430, Stator; 440, X-ray window. Detailed Implementation

[0032] See Figure 1 and Figure 2This CT tube (or X-ray CT tube, or X-ray tube) has an electron gun (component / device for emitting an electron beam) 110 and a linear array target assembly (hereinafter referred to as the array target assembly, or target assembly) within its housing 400. The housing is a vacuum chamber, mainly used to provide a low-resistance environment for the electron beam movement. The vacuum chamber includes a first chamber (or first receiving chamber) 100 and a second chamber (or second receiving chamber) 200. The electron gun is located in the first chamber, and its emitted electron beam (electron beam current) 130 is parallel to the target disk axis 240 of the array target assembly and enters the second chamber. The array target assembly (including the entire target disk) is located in the second chamber. Depending on the rotation angle of the target disk axis, the electron beam entering the second chamber bombards the target surface 231 of the target body 230 located in its path, thereby generating an X-ray beam 300. An X-ray window (hereinafter referred to as a window) 440 is provided on the side wall of the housing of the second chamber to allow X-rays to pass through. The target is located at the edge of the target disk. When the electron beam bombards the target (target surface) located at the edge of the target disk, the generated X-rays are emitted through the X-ray window. The target angle / tilt angle (or the taper of the target surface, when the target surface is a frustum) can be reasonably set using existing technology to facilitate the emission of X-rays.

[0033] Depending on the actual needs, the target angle / taper of the electron beam impact region can be varied, or even distorted. For example, a preferred embodiment is that the electron beam impact regions on the target surfaces of each target disk are located on the same helical surface, or in other words, each target surface (electron beam impact region) is a part of the same helical surface.

[0034] To prevent the front target from obstructing the rear target, a notch 220 is made on the front target to form an electron beam channel to the rear target. The size of the notch should meet the requirements for electron beam passage. When there are multiple notches forming the same electron beam channel (corresponding to the case of multiple target disks in front), the notches forming the same electron beam channel are aligned with each other, thus forming a straight electron beam channel parallel to the target disk axis. The electron beam channels leading to each target disk are arranged sequentially in the circumferential direction (either counterclockwise or clockwise). This allows an electron gun to emit beams parallel to the target disk axis. During the rotation of the target assembly, except for the target disk at the foremost edge, the electron beam channels of each target disk sequentially pass through the paths of the electron beams emitted by the relevant electron guns. The timely emitted electron beams pass through the corresponding electron beam channels (the corresponding notches on the front target disks) and bombard the target surface of the corresponding target disk (target body). The target surface generates X-rays due to the bombardment of the electron beams. For the target disk located at the foremost edge, since there are no other target disks blocking it in front, the timely emitted electron beams bombard its target surface when the target body (the part without notches) passes through the electron beam path, and the target surface generates X-rays due to the bombardment of the electron beams.

[0035] The target disk (target body) located at the rear does not obstruct any target disk and does not require notches to form electron beam channels. The number of notches for forming electron beam channels on other target disks (target bodies) is equal to the number of target disks (target bodies) located behind them, and these notches are used to form electron beam channels to each target body behind them. Therefore, the number of notches for forming electron beam channels on any target body is Nn or an integer multiple of Nn (corresponding to the case where a target disk has multiple electron beam channels), where N is the total number of target disks and n is the sequence number of the target disks from front to back (the target disk at the front is numbered 1, and the target disk at the rear is numbered N).

[0036] The electron beam bombardment areas on each target (target surface) are preferably distributed at equal intervals in the circumferential direction. Since the electron beam bombardment area of ​​each target, except for the foremost target disk, is the area corresponding to the corresponding electron beam channel, the electron beam channels and the electron beam bombardment areas on the foremost target disk are distributed at equal intervals in the circumferential direction. That is, the distance between any two adjacent electron beam channels and the distance between the electron beam bombardment area on the foremost target disk and the adjacent electron beam channel (angular distance at the center position) are equal. This angular distance is the quotient of 360° divided by the total number of targets (the total number of targets on all target disks). This makes the targets uniformly distributed in the circumferential direction, and the resulting X-ray sequence is also equally spaced.

[0037] Preferably, the electron beam channels leading to each target disk are arranged in the same order in the circumferential direction as the target disks are arranged in the same order in the axial direction.

[0038] The shape and size of the first and second chambers are determined according to actual needs. A beam channel (e.g., a channel connecting the two chambers) is provided between the first and second chambers to allow the electron beam to pass through. The vacuum level inside the chambers should be adapted to the movement of the electron beam to reduce resistance to the electron beam.

[0039] The electron gun can employ any suitable existing technology to generate an electron beam capable of bombarding a target surface and causing the target surface to generate an X-ray beam under its bombardment. For example, the electron gun may include a cathode for emitting electrons, a grid for controlling the electron beam, and a high-voltage anode for accelerating the electron beam. A beam modulation assembly 120 located outside the first receiving cavity can be used to adjust the electron beam and form the desired electron beam current. The beam modulation assembly can employ any suitable existing technology; for example, it can employ any one or more (including some and all) of the following components: a helical coil, a quadrupole magnet, and an electromagnetic lens. The number of each component (helical coil, quadrupole magnet, or electromagnetic lens) can be one or more. The electron beam can be focused according to actual needs, and the focal position and focal spot size of the electron beam can be changed.

[0040] The linear array target assembly includes several target disks 210 and a target disk shaft 240. The target disks are arranged sequentially along the axial direction (e.g., at equal intervals) and fixedly mounted on the target disk shaft. The targets on each target disk are distributed sequentially in the circumferential direction. Thus, during the rotation of the target disk shaft, each target is bombarded by an electron beam through its corresponding electron beam channel in sequence (the electron beam bombarding the foremost target does not pass through the electron beam channel set on the target disk). Under the impact of the electron beam, an X-ray beam array is formed, with the focal axial position changing sequentially. The emission time (period) of the electron beam can be set according to the number of targets and the rotation speed of the target disk shaft, etc. In other words, the electron beam emission mode (duration, interval) is coordinated with the number of targets and the rotation speed of the target disk shaft. Whenever the electron beam channel of a target disk (or the bombardment area of ​​the foremost target disk) is located in the electron beam path (during the process of passing through the electron beam path), the emitted electron beam hits the target surface of the corresponding target.

[0041] Based on the axial arrangement of the target disks, except for the target disk located at the front, the electron beam channel of each target disk rotates (misaligns) by an angle clockwise or counterclockwise relative to the electron beam channel of the previous target disk in the circumferential direction. This angle is equal to the quotient of 360° divided by the total number of targets. As a result, the electron beam bombardment areas of all targets are distributed at equal intervals (equiangular intervals) in the circumferential direction.

[0042] The target surface can be prepared using any suitable existing technology. For example, it can be made of a high-melting-point metal, and its shape, size, and target angle can be set according to the needs of the CT equipment. When appropriate, the target surface material can be placed only in the electron beam bombardment area.

[0043] The target angles (the angle between the target surface and the electron beam) of each target can usually be equal, but can also be set separately according to actual needs if necessary. For example, all target angles can be equal, or not all equal (partially equal), or not equal at all. According to the requirements of CT equipment, the target angles on the same target (the target angles of different parts on the target surface of the same target) can be fixed or variable values.

[0044] Apart from the notch on the target body, each target disc and target body can adopt the same structure. If necessary, such as according to the needs of CT detection, different structures can also be adopted, such as different target angles.

[0045] A helical coil 250 for electron beam focusing and adjustment can be installed on the front side of each target disk (in front of the electron beam bombardment area). The helical coil is located in the second chamber, and its axial through-hole (central through-hole) is set in the path of the electron beam, allowing the electron beam to pass through the corresponding helical coil. The high-speed electron beam can be focused and adjusted by the helical coils located on the front side of each target disk. By applying a corresponding current to the helical coil, the electron beam can be constrained and controlled, controlling the focus of the electron beam to fall on the target surface of the corresponding target (when the target rotates into the electron beam path) and form a focal spot of the required size. Thus, through the coordination of the beam adjustment assembly and each helical coil, the entire range of electron beam adjustment can be achieved.

[0046] Both ends of the target disk shaft are mounted via bearings 420. One end of the target disk shaft can be coaxially connected to the rotor 410 of the drive motor (e.g., via a coupling), thus the bearing between the rotor shaft and the stator 430 of the drive motor can be considered as the drive end bearing of the target disk shaft. The drive motor for the target disk shaft can employ any suitable existing technology; for example, it can have stator coils and rotor coils. A specific magnetic field generated by passing current through the stator coils can drive the rotor coils to rotate, thereby driving the target disk shaft to rotate via the rotor shaft. Alternatively, a specific magnetic field generated by passing a specific current through the stator coils can stop the rotating rotor coils from rotating, thereby stopping the target disk shaft from rotating.

[0047] For the purpose of vacuum sealing, the rotor (including rotor coils) can be housed within a housing, with corresponding portions of the housing shaped to fit the rotor; this portion of the housing can be considered part of the stator. Bearings between the rotor and stator are mounted on the housing (e.g., the outer ring of the bearing is fixedly mounted on a corresponding portion of the housing), thereby achieving a rotational connection between the rotor and stator.

[0048] If necessary, a heat dissipation system can be set up based on existing technology, and / or, heat dissipation-related structures (e.g., the material and shape of the housing) can be set up to achieve the required efficient heat dissipation.

[0049] Based on existing technology, the various parts can work in a coordinated manner with the support of software. For example, a signal coordination module can be set up for signal transmission and synchronization control between multiple target discs and multiple X-ray tubes (when the same CT equipment has multiple X-ray tubes).

[0050] The working method of this invention, especially the X-ray focus adjustment method, is as follows: electrons emitted by the cathode in the electron gun can be controlled by the grid in the electron gun to emit an electron beam; the high-voltage anode in the electron gun accelerates the electron beam into a high-speed electron beam; the beam-adjusting assembly focuses / constrains the electron beam entering it, reducing the diameter of the already diverged electron beam; the electromagnetic lens adjusts the focus and focal spot of the electron beam, so that the focus can be located on the target surface of the target body of each corresponding target disk as needed.

[0051] In the second chamber, helical coils are arranged on the front side of each target disk, positioned between the target disks and along the path of the high-speed electron beam. During operation, current is applied to the helical coils to further focus and adjust the passing high-speed electron beam. If appropriate, helical coils may be omitted, and adjustment can be achieved solely through the beam-tuning assembly.

[0052] This invention has the following characteristics: 1) High scanning speed. Conventional X-ray CT tubes emit X-rays from a single target disk and a single focal point. This invention emits X-rays from multiple target disks and multiple focal points, which can be switched rapidly. 7-9 of these tubes are statically arranged around the human body (the specific number depends on actual needs and design), working sequentially and employing similar detection technology. Its scanning speed far exceeds that of current conventional third-generation CT scanners, making it particularly suitable for coronary artery scanning in patients with arrhythmias.

[0053] 2) High image quality. For example, assuming the use of 9 new X-ray tubes, each with 6 target disks, based on existing technology, each X-ray target on each disk can generate 10-20 (or more) projection data points per hit. Thus, a single scan can generate approximately 1000 (or more) projection data points, far exceeding the dozens of projection data points of current static CT. Therefore, this solution can quickly reconstruct high-quality images.

[0054] 3) Low cost and long lifespan. Conventional X-ray CT tubes emit X-rays continuously from a single target disk, requiring high-speed rotation of the anode to dissipate heat, placing extremely high demands on the bearings and resulting in a short lifespan. This invention, with multiple target disks rotating at low speeds, can generate linearly moving X-rays, reducing bearing requirements, significantly lowering costs, and extending the tube's lifespan.

[0055] Unless otherwise specified, the preferred and optional technical means disclosed in this invention can be arbitrarily combined to form several different specific embodiments when one preferred or optional technical means is a further limitation of another technical means.

Claims

1. A channel-type X-ray linear array target assembly, comprising a target disk and a target disk axis, characterized in that... There are multiple target disks, which are installed sequentially on the target disk shaft. The edge of the target disk is provided with an annular target body. Except for the target disk located at the foremost side, for any target disk, the target disk in front of it is provided with a notch to form an electron beam channel to the target disk. The electron beam channel is aligned with the target surface on the corresponding target disk. The electron beam channels to each target disk are arranged sequentially in the circumferential direction.

2. The channel-type X-ray linear array target assembly as described in claim 1, characterized in that... There is a gap between adjacent target disks.

3. The channel-type X-ray linear array target assembly as described in claim 1, characterized in that... The number of target disks shall not be less than two, and the spacing between adjacent target disks shall be equal or unequal.

4. The channel-type X-ray linear array target assembly as described in claim 1, characterized in that... The electron impact region of the target has a target angle.

5. The channel-type X-ray linear array target assembly as described in claim 1, characterized in that... The electron impact region of the target is shaped like a frustum, with the frustum being smaller at the front and larger at the back, with the axis of the target disk as its axis; or, the electron impact region of the target is shaped like a helical surface, and the electron impact regions of each target are located on the same helical surface.

6. The channel-type X-ray linear array target assembly as described in claim 1, characterized in that... The number of targets on the same target disk is one; or, the number of targets on the same target disk is multiple, and the multiple targets are distributed on the target disk in an equidistant or unequal interval pattern.

7. A CT tube, comprising a housing, characterized in that... The housing contains a target assembly and an electron gun for generating an electron beam. The target assembly is a channel-type X-ray linear array target assembly as described in any one of claims 1-6. The electron beam direction of the electron gun is parallel to the axis of the target disk and faces the target assembly.

8. The CT tube as described in claim 7, characterized in that... The housing is a closed housing, and its cavity includes a first chamber and a second chamber. The first chamber can accommodate the electron gun and is provided with an electron beam current channel that connects to the second chamber. The second chamber can accommodate the target assembly. Each target disk may or may not be provided with a helical coil for electron beam current adjustment on its front side.

9. A CT device, comprising a CT tube for generating an X-ray beam, characterized in that... The CT tube is the CT tube according to any one of claims 7-8.

10. The CT device as described in claim 9, characterized in that... X-ray focus adjustment is performed in the following ways: the electron beam is focused by a beam-switching assembly; or, the electron beam is focused by a beam-switching assembly and a current is applied to the helical coils in front of each target disk, and the current is controlled to further adjust the high-speed electron beam passing through the helical coils, forming a focus on the target surface behind it with a focal spot of the desired size.

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