Rotating collimation type static CT imaging system and collimation method

Abstract

The present invention provides a rotating collimation type static CT imaging system and a collimation method, comprising: a control system; a gantry disposed on the ground; a single X-ray ring, the X-ray ring being disposed on the gantry and communicatively connected to a scanning timing controller; a single detection ring, the single detection ring being disposed on the gantry and communicatively connected to the scanning timing controller; a double-ring collimation system, the double-ring collimation system including a collimation driving device, a rotating frame, a first collimation ring and a second collimation ring, the collimation driving device being communicatively connected to a collimation controller, the rotating frame being rotatably arranged on the gantry and drivingly connected to the collimation driving device, the first collimation ring and the second collimation ring both being fixedly arranged on the rotating frame to rotate synchronously with the rotating frame, and a detection collimation area and an X-ray collimation area being correspondingly arranged obliquely radially. The present invention can not only realize the dynamic collimation function of the X-ray source and the dynamic collimation function of the detector, but also effectively reduce the radiation dose to the patient.

Description

Technical Field

[0001] The present invention relates to the technical field of static CT, and particularly to a rotating collimator type static CT imaging system and a collimation method. Background Art

[0002] Traditional CT consists of several major components including a gantry, a high-voltage generator, an X-ray tube, and detectors. The gantry is a rotating system, and the three main components, namely the high-voltage generator, the X-ray tube, and the detectors, are installed on the rotating gantry. Electric energy is generally transmitted to the rotating gantry through slip rings, and the power supply for the moving components on the gantry is transmitted through slip rings. The rotation of the gantry will bring huge acceleration, and all the components installed on the gantry have to bear huge centrifugal forces, which will cause great manufacturing difficulties for these components and affect the service life of the components. In order to improve its performance, including issues such as time resolution and dose, the rotation speed of the gantry is getting faster and faster. Now it has become a bottleneck restricting the development of CT and it is very difficult to further improve. In order to break through the current bottleneck, the next-generation revolutionary CT is recognized as static CT.

[0003] Static CT is defined as the sixth-generation CT in the development history of CT. Adopting a brand-new imaging method, it is an innovative slip-ring-free multi-source CT, which can obtain imaging characteristics of ultra-high speed, ultra-low radiation dose, and ultra-high-definition images, leading CT into the mesoscopic imaging stage.

[0004] The core components of static CT include a detector ring and a radiation source ring. The detector ring is configured with an annular detector, which is composed of multiple photon stream detectors. The radiation source ring is composed of distributed X-ray tubes or array-type integrated radiation sources.

[0005] In terms of structural design, static CT no longer uses slip rings and consists of a double-ring mechanical geometric structure composed of a detector ring and a radiation source ring. Among them, dozens to hundreds of radiation source foci are arranged on the radiation source ring, and a full-ring detector is arranged on the detector ring, so that the X-rays emitted by each radiation source focus can be imaged by the opposite detector. The distributed X-ray source foci on the radiation source ring alternately emit X-rays under the exposure control timing and collect images by the corresponding detector ring, essentially producing an effect similar to the ray source rotation projection of a spiral CT device, so that the time resolution of the CT device no longer depends on the mechanical rotation speed.

[0006] In static CT, the existing design method of the collimator has encountered challenges. In order to observe the target to be measured from various angles, the X-ray source needs to be exposed one by one. One problem encountered in this way is that the position of the corresponding X-ray source for the detector changes at a high speed each time, and there is no way to ensure that the pixel exposure moment of the corresponding detector is exactly facing the X-ray source. Summary of the Invention

[0007] In view of the above-mentioned disadvantages of the prior art, the technical problem to be solved by the present invention is to provide a rotation collimation type static CT imaging system and a collimation method, which can not only realize the dynamic collimation function of the X-ray source and the dynamic collimation function of the detector, but also effectively reduce the radiation dose to the patient. In addition, it can greatly exert the advantages of the static CT and improve the imaging quality of the static CT.

[0008] To solve the above technical problems, the present invention provides a rotation collimation type static CT imaging system, including:

[0009] A control system, which includes a CT host, a scan timing controller communicatively connected to the CT host, and a collimation controller communicatively connected to the CT host;

[0010] A gantry disposed on the ground;

[0011] A single X-ray ring, which is disposed on the gantry and communicatively connected to the scan timing controller. The X-ray ring includes a plurality of X-ray sources arranged in a circumferential array;

[0012] A single detection ring, which is disposed on the gantry and communicatively connected to the scan timing controller. The single detection ring is coaxially arranged on one side of the X-ray ring. The detection ring includes a plurality of detectors arranged in a circumferential array;

[0013] A double-ring collimation system, which includes a collimation driving device, a rotating frame, a first collimation ring, and a second collimation ring. The collimation driving device is communicatively connected to the collimation controller. The rotating frame is rotatably arranged on the gantry and is drivingly connected to the collimation driving device. The first collimation ring and the second collimation ring are both fixedly arranged on the rotating frame to rotate synchronously with the rotating frame. The first collimation ring has an X-ray collimation area and is coaxially located inside the X-ray ring. The second collimation ring has a detection collimation area and is coaxially located inside the detection ring. The detection collimation area and the X-ray collimation area are correspondingly arranged radially and obliquely.

[0014] Preferably, the number of the detection collimation areas is multiple and arranged in a circumferential array, and the number of the X-ray collimation areas is multiple and arranged in a circumferential array. All the detection collimation areas and the X-ray collimation areas correspond to each other one by one.

[0015] Preferably, the first collimation ring includes a first circular ring body and a collimation hole structure radially penetrating through the first circular ring body. The collimation hole structure is used to restrict the emission range and emission angle of the X-rays emitted by the X-ray source.

[0016] Preferably, the collimation hole structure includes an arc-shaped long and narrow hole, and the center of the circle corresponding to the arc-shaped long and narrow hole is located on the axis of the first circular ring body.

[0017] Preferably, the detection collimation area of the second collimation ring has a grid structure.

[0018] Preferably, the X-ray source includes an arc-shaped extended vacuum tube, the center of the circle corresponding to the vacuum tube is located on the axis of the X-ray ring, and a plurality of windows allowing X-rays to pass through are provided on the radially inward tube wall of the vacuum tube; the X-ray collimation area of the first collimation ring is radially aligned with at least one window.

[0019] Preferably, the X-ray source further includes a cathode end and an anode target located in the vacuum tube, the number of cathode ends and the number of anode targets are both multiple and correspond one by one, and at least one anode target is radially aligned with a single window.

[0020] Preferably, the rotating frame has a circular ring structure, and the rotating frame, the first collimation ring and the second collimation ring are coaxially arranged.

[0021] Preferably, all the detectors are circumferentially divided into multiple groups along the detection ring, and all the detectors belonging to the same group are used to simultaneously receive the X-rays passing through the detection collimation area.

[0022] The present invention also provides a collimation method using the rotating collimation type static CT imaging system, including the following steps:

[0023] Set a preset scanning program on the CT host;

[0024] At least one X-ray source of the X-ray ring emits narrow-beam X-rays according to the preset scanning program under the control of the scanning timing controller; meanwhile, the collimation driving device drives the rotating frame under the control of the collimation controller, and the first collimation ring and the second collimation ring rotate synchronously driven by the rotating frame, and based on the preset scanning program, the X-ray collimation area of the first collimation ring is always radially aligned with the X-ray source that is emitting X-rays, and the detection collimation area of the second collimation ring is always radially aligned with the detector that is detecting X-rays;

[0025] The exposure information collected by all the detectors is fed back to the CT host, and a CT image of the object to be measured is formed in the CT host.

[0026] As described above, the rotating collimation type static CT imaging system and collimation method of the present invention have the following beneficial effects: The control system includes a CT host, a scan timing controller communicatively connected to the CT host, and a collimation controller communicatively connected to the CT host. The CT host has a human-computer interaction system and an image forming system. The scan mode program in the scan timing controller can be input or modified by the CT host. The collimation mode program in the collimation controller is adapted to the scan mode program. The gantry is installed on the ground and serves as the main load-bearing and installation structure of the rotating collimation type static CT imaging system. The main innovation point of the rotating collimation type static CT imaging system of the present invention lies in: The double-ring collimation system includes a collimation driving device, a rotating frame, a first collimation ring, and a second collimation ring. The collimation driving device is communicatively connected to the collimation controller. The rotating frame is rotatably arranged on the gantry and is drivingly connected to the collimation driving device. The first collimation ring and the second collimation ring are both fixedly arranged on the rotating frame to rotate synchronously with the rotating frame. The first collimation ring has an X-ray collimation area and the first collimation ring is coaxially located within the X-ray ring. The second collimation ring has a detection collimation area and the second collimation ring is coaxially located within the detection ring. The detection collimation area and the X-ray collimation area are arranged to correspond to each other radially and obliquely. That is to say, when the X-ray ring switches different X-ray emission points according to a preset scan sequence, the collimation driving device drives the rotating frame to rotate at a high speed under the control of the collimation controller, and then drives the first collimation ring and the second collimation ring to rotate synchronously at a high speed, so that the X-ray collimation area of the first collimation ring can follow and radially align with the above-mentioned X-ray emission points, and the detection collimation area of the second collimation ring can follow and radially align with the X-ray detection points. When the X-ray source exposes point by point, the detection points of the detector are also constantly changing. The first collimation ring and the second collimation ring rotate synchronously at a high speed, which can ensure that at each exposure point, the X-ray collimation area of the first collimation ring can accurately collimate the emitted X-rays, reducing the dose of X-rays; the detection collimation area of the second collimation ring can accurately collimate the incident X-rays, effectively preventing the influence of stray X-rays on the image quality and improving the image quality. This design method not only realizes the collimation function of the X-ray source and the collimation function of the detector, but also effectively reduces the radiation dose to the patient. Therefore, the rotating collimation type static CT imaging system of the present invention can not only realize the dynamic collimation function of the X-ray source and the dynamic collimation function of the detector, but also effectively reduce the radiation dose to the patient. In addition, it can greatly exert the advantages of static CT and improve the imaging quality of static CT. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It shows a perspective view of the rotating collimation type static CT imaging system of the present invention;

[0028] Figure 2 It shows a front view of the rotating collimation type static CT imaging system of the present invention;

[0029] Figure 3 Shown as a sectional view along Figure 2 section line A-A in

[0030] Figure 4 Shown as Figure 3 an enlarged view of part B in

[0031] Figure 5 a perspective view of the double-ring collimation system;

[0032] Figure 6 a perspective view of the X-ray ring;

[0033] Figure 7 a perspective view of the X-ray source;

[0034] Figure 8 Shown as a partial sectional view of the X-ray source.

[0035] Description of Component Labels

[0036] 1 Control System

[0037] 11 CT Mainframe

[0038] 12 Scanning Timing Controller

[0039] 13 Collimation Controller

[0040] 2 Gantry

[0041] 3 X-ray Ring

[0042] 31 X-ray Source

[0043] 311 Vacuum Tube

[0044] 312 Cathode End

[0045] 313 Anode Target

[0046] 314 Temperature Sensor

[0047] 315 Window

[0048] 4 Detection Ring

[0049] 41 Detector

[0050] 5 Double-ring Collimation System

[0051] 51 First Collimation Ring

[0052] 511 First Torus

[0053] 512 Arc-shaped Narrow Hole

[0054] 52 Second Collimation Ring Detailed Implementation Manner

[0055] The following specific embodiments illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0056] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the limited conditions for the implementation of the present invention. Therefore, they do not have substantial technical significance. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle", and "one" cited in this specification are only for the convenience of clear narration, and are not used to limit the scope for the implementation of the present invention. The change or adjustment of their relative relationships, without substantial change in the technical content, should also be regarded as the scope for the implementation of the present invention.

[0057] The present invention provides a rotating collimation type static CT imaging system. The basic imaging principle of this rotating collimation type static CT imaging system is as follows: Use an X-ray beam and an X-ray detector with extremely high sensitivity to perform layer-by-layer cross-sectional scanning on a certain part of the human body. The scintillating material on the X-ray detector receives the X-rays passing through this layer and converts them into visible light. Then, it is converted into an electrical signal by a photoelectric converter, amplified, and then converted into a digital signal through analog / digital conversion processing and input into a computer for processing. In the computer, the selected layer is divided into several cubes with the same volume, which are called voxels (Voxel). After the information obtained from the layer-by-layer cross-sectional scanning is calculated, the X-ray attenuation coefficient or absorption coefficient of each voxel is obtained, and then arranged into a matrix, that is, a voxel digital matrix. The digital information in the voxel digital matrix is converted into small squares with different gray levels from black to white, which are called pixels (Pixel) in a two-dimensional projection. Arranged in a tomographic manner, they constitute a CT image.

[0058] In existing static CTs, the X-ray source and the detector need to be fixedly arranged on the entire annular gantry. To maximize the utilization of X-rays and space and at the same time reduce the dose, the best way is to use multi-row detectors. When using multi-row detectors, in order to reduce the influence of stray X-rays, a collimator needs to be installed in front of the detector. Since the X-ray source and the detector in existing static CTs are in a fixed state and the relative directions of the X-ray source and the detector need to be constantly changed, existing collimators are no longer applicable.

[0059] To meet the collimation requirements of static CT,

[0060] The present invention proposes to use a dynamically collimating structure with high-speed rotation on a static CT to achieve the purpose of collimating the X-ray source and detector for each exposure. That is,

[0061] As Figure 1 , Figure 2 and Figure 3 shown, the present invention provides a rotating collimation type static CT imaging system, including:

[0062] A control system 1, which includes a CT host 11, a scanning timing controller 12 communicatively connected to the CT host 11, and a collimation controller 13 communicatively connected to the CT host 11;

[0063] A gantry 2 installed on the ground;

[0064] A single X-ray ring 3, the X-ray ring 3 is installed on the gantry 2 and communicatively connected to the scanning timing controller 12, and the X-ray ring 3 includes a plurality of X-ray sources 31 arranged in a circumferential array;

[0065] A single detection ring 4, the single detection ring 4 is installed on the gantry 2 and communicatively connected to the scanning timing controller 12, the single detection ring 4 is coaxially arranged on one side of the X-ray ring 3, and the detection ring 4 includes a plurality of detectors 41 arranged in a circumferential array;

[0066] A double-ring collimation system 5 (see specifically Figure 5 ), the double-ring collimation system 5 includes a collimation driving device, a rotating frame, a first collimation ring 51 and a second collimation ring 52. The collimation driving device is communicatively connected to the collimation controller 13. The rotating frame is rotatably arranged on the gantry 2 and is drivingly connected to the collimation driving device. Both the first collimation ring 51 and the second collimation ring 52 are fixedly arranged on the rotating frame to rotate synchronously with the rotating frame. The first collimation ring 51 has an X-ray collimation area and the first collimation ring 51 is coaxially located inside the X-ray ring 3. The second collimation ring 52 has a detection collimation area and the second collimation ring 52 is coaxially located inside the detection ring 4. The detection collimation area and the X-ray collimation area are arranged to correspond to each other obliquely in the radial direction.

[0067] In the present invention, the control system 1 includes a CT host 11, a scan timing controller 12 communicatively connected to the CT host 11, and a collimation controller 13 communicatively connected to the CT host 11. The CT host 11 has a human-computer interaction system and an image formation system. The scan mode program in the scan timing controller 12 can be input or modified by the CT host 11. The collimation mode program in the collimation controller 13 is adapted to the scan mode program. The gantry 2 is provided on the ground, and the gantry 2 is the main load-bearing and installation structure of the rotating collimation type static CT imaging system. The main innovation of the rotating collimation type static CT imaging system of the present invention lies in that: the double-ring collimation system 5 includes a collimation driving device (not shown), a rotating frame (not shown), a first collimation ring 51, and a second collimation ring 52. The collimation driving device is communicatively connected to the collimation controller 13. The rotating frame is rotatably arranged on the gantry 2 and is drivingly connected to the collimation driving device. The first collimation ring 51 and the second collimation ring 52 are both fixedly arranged on the rotating frame to rotate synchronously with the rotating frame. The first collimation ring 51 has an X-ray collimation area and the first collimation ring 51 is coaxially located within the X-ray ring 3. The second collimation ring 52 has a detection collimation area and the second collimation ring 52 is coaxially located within the detection ring 4. The detection collimation area and the X-ray collimation area are arranged to be radially corresponding and inclined. That is to say,

[0068] When different X-ray emission points are switched in the X-ray ring 3 according to a preset scan order, the collimation driving device drives the rotating frame to rotate at a high speed under the control of the collimation controller 13, and then drives the first collimation ring 51 and the second collimation ring 52 to rotate synchronously at a high speed, so that the X-ray collimation area of the first collimation ring 51 can follow and radially align with the above-mentioned X-ray emission points, and the detection collimation area of the second collimation ring 52 can follow and radially align with the X-ray detection points. When the X-ray source 31 exposes point by point, the detection points of the detector 41 are also constantly changing. The first collimation ring 51 and the second collimation ring 52 rotate synchronously at a high speed, which can ensure that at each exposure point, the X-ray collimation area of the first collimation ring 51 can accurately collimate the emitted X-rays, reducing the dose of X-rays; the detection collimation area of the second collimation ring 52 can accurately collimate the incident X-rays, effectively preventing the influence of stray X-rays on the image quality and improving the image quality. This design method not only realizes the collimation function of the X-ray source 31 and the collimation function of the detector 41, but also effectively reduces the radiation dose to the patient.

[0069] Therefore, the rotating collimation type static CT imaging system of the present invention can not only realize the dynamic collimation function of the X-ray source 31 and the dynamic collimation function of the detector 41, but also effectively reduce the radiation dose to the patient. In addition, it can greatly exert the advantages of static CT and improve the imaging quality of static CT.

[0070] When at least two of all the above-mentioned detectors 41 can emit X-rays simultaneously, the number of the above-mentioned detection collimation regions is multiple and in a circumferential array, the number of the above-mentioned X-ray collimation regions is multiple and in a circumferential array, and all the detection collimation regions and the X-ray collimation regions correspond to each other one by one. During operation, the collimation driving device drives the rotating frame to rotate at a high speed under the control of the collimation controller 13, the first collimation ring 51 and the second collimation ring 52 rotate synchronously at a high speed, and the multiple X-ray collimation regions of the first collimation ring 51 can respectively follow and radially align with the multiple above-mentioned X-ray emission points, and the multiple detection collimation regions of the second collimation ring 52 can respectively follow and radially align with the multiple above-mentioned X-ray detection points.

[0071] To simplify the structure of the above-mentioned first collimation ring 51, the first collimation ring 51 includes a first circular ring body 511 and a collimation hole structure that penetrates the first circular ring body 511 radially, and the collimation hole structure is used to restrict the emission range and emission angle of the X-rays emitted by the X-ray source 31.

[0072] To form a narrow beam of X-rays, the above-mentioned collimation hole structure includes an arc-shaped long and narrow hole 512, and the center of the circle corresponding to the arc-shaped long and narrow hole 512 is located on the axis of the first circular ring body 511.

[0073] To avoid the influence of X-ray scattering or reflection on the imaging quality, the detection collimation regions of the above-mentioned second collimation ring 52 have a grid structure.

[0074] As Figure 4 、 Figure 6 、 Figure 7 and Figure 8 shown, as an embodiment of the above-mentioned X-ray source 31: the above-mentioned X-ray source 31 includes a vacuum tube 311, in the vacuum tube 311 there are provided a cathode end 312 that emits an electron beam, an anode target 313 bombarded by the electron beam, and a deflection structure that controls the movement trajectory of the electron beam. The deflection structure can be an electromagnetic coil.

[0075] As an embodiment of the above-mentioned X-ray source 31, the above-mentioned X-ray source 31 further includes a grid, and the grid can be used to control the dynamic movement trajectory of the electron beam and directly change the tilt irradiation angle. The grid can achieve multiple functions at the same time. One is to change the focus position to achieve the adjustment function of the tilt irradiation angle, and the other is to control the intensity of the electron beam to achieve the function of dynamic current control, which can reduce the local temperature of the anode target 313 and improve the service life of the anode target 313. In addition, the X-ray source 31 also requires a high-voltage generator to drive.

[0076] To detect the temperature of the above-mentioned anode target 313, the above-mentioned X-ray source 31 further includes a temperature sensor 314, and the temperature sensor 314 is arranged on the side of the anode target 313 facing away from the cathode end 312 and is communicatively connected to the CT host 11.

[0077] To reduce the outer diameter size of the above-mentioned X-ray ring 3, the above-mentioned cathode end 312 and the anode target 313 are arranged in alignment along the direction parallel to the axis of the X-ray ring 3. A window 315 is provided on the radially inward tube wall of the above-mentioned vacuum tube 311. The window 315 is radially aligned with the anode target 313 along the X-ray ring 3. The anode target 313 has a thick target structure to direct the X-rays generated by the electron beam bombardment from the bombardment surface of the electron beam towards the window 315.

[0078] Furthermore, to improve the compactness of the above-mentioned X-ray source 31, the above-mentioned vacuum tube 311 extends in an arc with the axis of the X-ray ring 3 as the center line. The number of the above-mentioned cathode ends 312 and the number of the anode targets 313 are both multiple and correspond one by one. All the cathode ends 312 are arranged in sequence along the extension direction of the vacuum tube 311, and all the anode targets 313 are arranged in sequence along the extension direction of the vacuum tube 311.

[0079] Since the above-mentioned anode target 313 has a thick target structure, to direct the X-rays from the bombardment surface of the electron beam towards the window 315, the side surface of the above-mentioned anode target 313 bombarded by the electron beam is a wedge-shaped surface.

[0080] To improve the integration of the above-mentioned X-ray source 31, the above-mentioned X-ray source 31 includes a vacuum tube 311 extending in an arc. The center corresponding to the vacuum tube 311 is located on the axis of the X-ray ring 3. A plurality of windows 315 allowing X-rays to pass through are provided on the radially inward tube wall of the vacuum tube 311; the X-ray collimation area of the above-mentioned first collimation ring 51 is radially aligned with at least one window 315. For example, three windows 315 in an arc array are provided on a single vacuum tube 311. A single X-ray collimation area can be aligned with a single window 315, can be aligned with two windows 315 simultaneously, or can be aligned with three windows 315 simultaneously, so as to adjust the scanning range and radiation dose.

[0081] To improve the integration of the above-mentioned X-ray source 31, the above-mentioned X-ray source 31 further includes a cathode end 312 and an anode target 313 located in the vacuum tube 311. The number of the cathode ends 312 and the number of the anode targets 313 are both multiple and correspond one by one. At least one anode target 313 is radially aligned with a single window 315.

[0082] To improve the connection stability between the above-mentioned first collimation ring 51 and the second collimation ring 52, the above-mentioned rotating frame has a circular ring structure, and the rotating frame, the first collimation ring 51 and the second collimation ring 52 are coaxially arranged.

[0083] In addition, all the above-mentioned detectors 41 are circumferentially divided into multiple groups along the detection ring 4. All the detectors 41 belonging to the same group are used to simultaneously receive the X-rays passing through the detection collimation area.

[0084] The present invention also provides a collimation method using the above-mentioned rotation collimation type static CT imaging system, comprising the following steps:

[0085] Set a preset scanning program on the CT host 11;

[0086] At least one X-ray source 31 of the X-ray ring 3 emits narrow-beam X-rays according to the preset scanning program under the control of the scanning timing controller 12; meanwhile, the collimation driving device drives the rotating frame under the control of the collimation controller 13, and the first collimation ring 51 and the second collimation ring 52 rotate synchronously driven by the rotating frame, and based on the preset scanning program, the X-ray collimation area of the first collimation ring 51 is always radially aligned with the X-ray source 31 that is emitting X-rays, and the detection collimation area of the second collimation ring 52 is always radially aligned with the detector that is detecting X-rays;

[0087] The exposure information collected by all the detectors 41 is fed back to the CT host 11, and a CT image of the object to be measured is formed in the CT host 11.

[0088] The collimation method of the present invention can not only achieve the dynamic collimation function of the X-ray source 31 and the dynamic collimation function of the detector 41, but also effectively reduce the radiation dose to the patient. In addition, it can greatly exert the advantages of the static CT and improve the imaging quality of the static CT.

[0089] In summary, the rotation collimation type static CT imaging system and the collimation method of the present invention can not only achieve the dynamic collimation function of the X-ray source and the dynamic collimation function of the detector, but also effectively reduce the radiation dose to the patient. In addition, it can greatly exert the advantages of the static CT and improve the imaging quality of the static CT. Therefore, the present invention effectively overcomes various disadvantages in the prior art and has high industrial utilization value.

[0090] The above embodiments are only illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A rotary collimation type static CT imaging system, characterized in that, Comprising: A control system (1), the control system (1) includes a CT host (11), a scan timing controller (12) communicatively connected to the CT host (11), and a collimation controller (13) communicatively connected to the CT host (11); A gantry (2) provided on the ground; A single X-ray ring (3), the X-ray ring (3) is provided on the gantry (2) and communicatively connected to the scan timing controller (12), the X-ray ring (3) includes a plurality of X-ray sources (31) arranged in a circumferential array; A single detection ring (4), the single detection ring (4) is provided on the gantry (2) and communicatively connected to the scan timing controller (12), the single detection ring (4) is coaxially arranged on one side of the X-ray ring (3), and the detection ring (4) includes a plurality of detectors (41) arranged in a circumferential array; A double-ring collimation system (5), the double-ring collimation system (5) includes a collimation drive device, a rotating frame, a first collimation ring (51) and a second collimation ring (52), the collimation drive device is communicatively connected to the collimation controller (13), the rotating frame is rotatably arranged on the gantry (2) and is drivingly connected to the collimation drive device, the first collimation ring (51) and the second collimation ring (52) are both fixedly arranged on the rotating frame to rotate synchronously with the rotating frame, the first collimation ring (51) has an X-ray collimation area and the first collimation ring (51) is coaxially located inside the X-ray ring (3), the second collimation ring (52) has a detection collimation area and the second collimation ring (52) is coaxially located inside the detection ring (4), and the detection collimation area and the X-ray collimation area are arranged to correspond to each other radially and obliquely.

2. The rotational collimation type static CT imaging system according to claim 1, wherein: The number of the detection collimation areas is multiple and arranged in a circumferential array, the number of the X-ray collimation areas is multiple and arranged in a circumferential array, and all the detection collimation areas and the X-ray collimation areas correspond to each other one by one.

3. The rotating collimator type static CT imaging system according to claim 1, wherein: The first collimation ring (51) includes a first circular ring body (511) and a collimation hole structure radially penetrating the first circular ring body (511), and the collimation hole structure is used to restrict the emission range and emission angle of the X-rays emitted by the X-ray sources (31).

4. The rotational collimation type static CT imaging system according to claim 3, wherein: The collimation hole structure includes an arc-shaped long and narrow hole (512), and the center of the circle corresponding to the arc-shaped long and narrow hole (512) is located on the axis of the first circular ring body (511).

5. The rotational collimation type static CT imaging system according to claim 1, characterized in that: The detection collimation area of the second collimation ring (52) has a grid structure.

6. The rotation collimation type static CT imaging system according to claim 1, wherein: The X-ray source (31) includes an arc-shaped extended vacuum tube (311), the center of the circle corresponding to the vacuum tube (311) is located on the axis of the X-ray ring (3), and a plurality of windows (315) allowing X-rays to pass through are provided on the inner radial wall of the vacuum tube (311); the X-ray collimation area of the first collimation ring (51) is radially aligned with at least one window (315).

7. The rotating collimator type static CT imaging system according to claim 6, characterized in that: The X-ray source (31) further includes a cathode end (312) and an anode target (313) located inside the vacuum tube (311), the number of the cathode ends (312) and the number of the anode targets (313) are both multiple and correspond to each other one by one, and at least one anode target (313) is radially aligned with a single window (315).

8. The rotation collimation type static CT imaging system according to claim 1, wherein: The rotating frame has a circular ring structure, and the rotating frame, the first collimation ring (51) and the second collimation ring (52) are coaxially arranged.

9. The rotating collimator type static CT imaging system according to claim 1, wherein: All the detectors (41) are circumferentially divided into multiple groups along the detection ring (4), and all the detectors (41) belonging to the same group are used to simultaneously receive the X-rays passing through the detection collimation area.

10. A collimation method using a rotating collimation type static CT imaging system according to any one of claims 1 to 9, characterized in that, Including the following steps: Set a preset scanning program on the CT host (11); At least one X-ray source (31) of the X-ray ring (3) emits narrow-beam X-rays according to the preset scanning program under the control of the scanning timing controller (12); meanwhile, the collimation driving device drives the rotating frame under the control of the collimation controller (13), and the first collimation ring (51) and the second collimation ring (52) rotate synchronously under the drive of the rotating frame, and based on the preset scanning program, the X-ray collimation area of the first collimation ring (51) is always radially aligned with the X-ray source (31) that is emitting X-rays, and the detection collimation area of the second collimation ring (52) is always radially aligned with the detector (41) that is detecting X-rays; The exposure information collected by all the detectors (41) is fed back to the CT host (11), and a CT image of the object to be measured is formed in the CT host (11).

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