CN209863859U - Front collimation device for static CT imaging system and static CT imaging system thereof - Google Patents
Front collimation device for static CT imaging system and static CT imaging system thereof Download PDFInfo
- Publication number
- CN209863859U CN209863859U CN201920223101.3U CN201920223101U CN209863859U CN 209863859 U CN209863859 U CN 209863859U CN 201920223101 U CN201920223101 U CN 201920223101U CN 209863859 U CN209863859 U CN 209863859U
- Authority
- CN
- China
- Prior art keywords
- ring
- beam limiting
- inner ring
- static
- outer ring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
- A61B6/02—Devices for diagnosis sequentially in different planes; Stereoscopic radiation diagnosis
- A61B6/03—Computerised tomographs
- A61B6/032—Transmission computed tomography [CT]
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
- A61B6/40—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment with arrangements for generating radiation specially adapted for radiation diagnosis
- A61B6/4007—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment with arrangements for generating radiation specially adapted for radiation diagnosis characterised by using a plurality of source units
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
- A61B6/42—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment with arrangements for detecting radiation specially adapted for radiation diagnosis
- A61B6/4266—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment with arrangements for detecting radiation specially adapted for radiation diagnosis characterised by using a plurality of detector units
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
- A61B6/44—Constructional features of apparatus for radiation diagnosis
- A61B6/4429—Constructional features of apparatus for radiation diagnosis related to the mounting of source units and detector units
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
- A61B6/54—Control of apparatus or devices for radiation diagnosis
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Medical Informatics (AREA)
- Radiology & Medical Imaging (AREA)
- Molecular Biology (AREA)
- Biophysics (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Optics & Photonics (AREA)
- Pathology (AREA)
- Physics & Mathematics (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- High Energy & Nuclear Physics (AREA)
- Surgery (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Pulmonology (AREA)
- Theoretical Computer Science (AREA)
- Apparatus For Radiation Diagnosis (AREA)
Abstract
The utility model discloses a preceding collimating device for static CT imaging system, include: the beam limiting inner ring, the beam limiting outer ring, at least two transmission assemblies and a plurality of supporting assemblies are arranged on the beam limiting inner ring; wherein, the beam limiting inner ring and the beam limiting outer ring are arranged between the ray source ring and the detector ring in parallel; the beam limiting outer ring is fixedly arranged; the beam limiting inner ring can move relative to the beam limiting outer ring under the action of the transmission assembly and the support assembly, so that the beam limiting width between the beam limiting inner ring and the beam limiting outer ring is changed. The front collimating device for the static CT imaging system drives the beam limiting inner ring to move through the transmission assembly, and can continuously adjust the beam limiting width between the beam limiting inner ring and the beam limiting outer ring, so that the layer thickness of CT scanning is adjusted. The front collimating device with the double-ring structure is suitable for being used in a static CT imaging system with a whole-ring structure of a ray source and a detector. The utility model discloses the static CT imaging system of collimation device before including above-mentioned simultaneously.
Description
Technical Field
The utility model relates to a preceding collimating device for static CT imaging system relates to the static CT imaging system including above-mentioned preceding collimating device simultaneously, belongs to X ray radiation imaging field.
Background
Ct (computed tomography) is an abbreviation for computed tomography. The CT scanner is a powerful medical image diagnosis device, and it uses X-ray to make layer-by-layer transverse scanning on a certain range of human body to obtain projection information, then uses computer to make data processing and image reconstruction. The imaging process of the X-ray mainly comprises the following steps: the X-ray source generates X-ray photons, and the X-ray photons are emitted to all directions along a straight line at the focus of the X-ray source; among the X-photons entering the imaged object, a portion is directly absorbed by atoms of the imaged object; a portion of the X-photons, i.e. direct X-photons, which information is used for image reconstruction, penetrate directly through the object to be imaged to the detector opposite the X-ray source. However, in practice, a part of the X-photons, i.e. scattered X-photons, collide with atoms of the object to be imaged to change the direction of motion and lose part of the energy. The scattered X-photons do not meet the requirements of an image reconstruction algorithm, and even if the scattered X-photons reach a detector, the scattered X-photons cannot contribute to imaging, but if the scattered X-photons cannot be eliminated, the noise of a reconstructed image is increased, and the quality of a CT image is influenced.
In order to solve the problem of X-ray scattering, in a conventional CT scanner provided with a ray source and an arc-shaped detector assembly, a front collimating device is generally arranged on one side of the X-ray source facing a detector by taking a focus of the X-ray source as a circle center, fan-shaped X-rays emitted from the focus penetrate through the front collimating device, the front collimating device adjusts layer thickness parameters by controlling the width of an X-ray beam and shields the harm of invalid scattered X-rays to a human body, and the front collimating device can be tightly attached to an emission window of the X-rays.
At present, in static CT imaging systems with a ring-shaped source of several sources, there is also a similar pre-collimator. For example, the invention patent application with publication number CN102379716A discloses a static CT scanner system, wherein the X-ray source system includes a plurality of X-ray source modules based on carbon nanotubes, the plurality of X-ray source modules are uniformly distributed on an annular track, and a collimator is correspondingly disposed below each X-ray source module, and the plurality of collimators form a collimator ring; the detector system comprises a plurality of detector modules, and the detection surfaces of the plurality of detector modules form an annular ring and are then placed in parallel with the annular track; the X-ray source system can project the emitted X-ray beams onto a detection surface of the detector system through a collimator slit of the collimator.
However, for a static CT imaging system having a ring-shaped source of closely spaced multiple focal spot sources, the above-described way of providing the front collimator in one-to-one correspondence with the X-ray sources is not applicable. For example, in the invention patent application with publication number CN105361900A, a static real-time CT imaging system and an imaging control method thereof are disclosed, the static CT imaging system is composed of an annular detector and an annular X-ray source, and the fan-shaped X-rays emitted from each focal point of the annular X-ray source are overlapped with the fan-shaped X-rays emitted from the adjacent focal points, so that a corresponding single front collimator cannot be arranged at the X-ray outlet of each X-ray source for beam limitation, like the conventional spiral CT.
Disclosure of Invention
The utility model aims to solve the first technical problem that a preceding collimating device for static CT imaging system is provided.
Another technical problem to be solved by the present invention is to provide a static CT imaging system including the front collimator.
In order to realize the technical purpose, the utility model adopts the following technical scheme:
according to the utility model discloses an aspect provides a preceding collimating device for static CT imaging system, include: the beam limiting inner ring, the beam limiting outer ring, at least two transmission assemblies and a plurality of supporting assemblies are arranged on the beam limiting inner ring;
the beam limiting inner ring and the beam limiting outer ring are arranged between the ray source ring and the detector ring in parallel; the beam limiting outer ring is fixedly arranged; the beam limiting inner ring can move relative to the beam limiting outer ring under the action of the transmission assembly and the support assembly, so that the beam limiting width between the beam limiting inner ring and the beam limiting outer ring is changed.
Preferably, the transmission assembly comprises a motor, a motor frame, a coupler, a screw fixed end bearing seat, a screw floating end bearing seat and a beam-limiting inner ring adapter;
the lead screw floating end bearing block is fixed on the detector support, the lead screw fixed end bearing block is fixed on the support outer ring, the motor is arranged on the outer side of the support outer ring through the motor frame, the motor is connected with the lead screw through the coupler, and the lead screw is provided with the beam-limiting inner ring adapter; the beam-limiting inner ring adapter is connected with the beam-limiting inner ring;
when the motor rotates, the motor drives the screw rod to rotate, and the beam limiting inner ring is driven to move relative to the beam limiting outer ring through the beam limiting inner ring adapter.
Preferably, the support assembly comprises an optical axis guide rail, an outer ring switching support and an inner ring moving switching piece; wherein the content of the first and second substances,
one end of the optical axis guide rail is connected with the detector ring, and the other end of the optical axis guide rail is connected with the support outer ring; the beam limiting inner ring is connected with the optical axis guide rail through the inner ring moving adapter and can freely move on the optical axis guide rail; the beam limiting outer ring is connected with the optical axis guide rail through the outer ring switching support, and the beam limiting outer ring is fixed.
Preferably, the transmission assembly and the support assembly are respectively arranged in a mounting gap between two adjacent ray source modules in the ray source ring.
Preferably, the two transmission assemblies are symmetrically arranged in two opposite mounting gaps, and the plurality of support assemblies are respectively arranged in the rest mounting gaps.
Preferably, the X-ray shielding device further comprises an X-ray shielding inner ring and an X-ray shielding outer ring, the X-ray shielding inner ring is arranged between the beam limiting inner ring and the detector ring, and the X-ray shielding outer ring is arranged on the supporting outer ring.
Preferably, the beam limiting inner ring and the beam limiting outer ring have the same diameter, and the end faces of the speed limiting inner ring and the beam limiting outer ring are parallel.
Preferably, the inner and outer restraint rings are circular ring structures made of metal materials, the cross section of each ring structure is L-shaped, and a layer of lead sheet is adhered to the inner side of each ring structure.
Preferably, the two transmission assemblies are driven synchronously through a control system.
Preferably, the control system comprises a computer, a main controller, a motor driver, a motor, an encoder and a limit switch, wherein the motor driver, the motor, the encoder and the limit switch are respectively provided with 2 groups.
Preferably, the limit switch is an infrared photoelectric switch, the limit switch is arranged on the detector support and is fixed in position, and the limit switch stop block is arranged on the beam limiting inner ring.
According to a second aspect of the embodiments of the present invention, there is provided a static CT imaging system including the above-mentioned front collimator. The static CT imaging system also comprises a ray source ring and a detector ring which are axially arranged in parallel; the radiation source ring consists of a plurality of X-ray sources which are closely arranged into a ring shape, and the detector ring consists of a plurality of detectors which are closely arranged into a ring shape;
under the control of the scanning time sequence controller, each X-ray source emits X-rays according to a scanning time sequence, and the X-rays irradiate the corresponding detector after passing through the front collimating device.
The utility model provides a preceding collimating device for static CT imaging system, restraint the inner ring and restraint the outer loop by the limit and constitute, drive the limit through drive screw and restraint the inner ring and remove, can restraint the width to the limit between the inner ring and the limit and restraint the outer loop and carry out continuous adjustment, can adjust the bed thickness of CT scanning. The front collimating device with the double-ring structure is suitable for being used in a static CT imaging system with a whole-ring structure of a ray source and a detector, is used for limiting beams of X rays emitted by a multi-focus ray source, and cannot influence the X rays emitted by all the ray sources. The front collimating device with the double-ring structure has the advantages of novel structure, good beam limiting adjustment and shielding effects on X-rays, simple structure and low cost.
Drawings
FIG. 1 is a schematic structural view of a static CT imaging system showing a source ring and a detector ring;
FIG. 2 is a schematic view of a focal spot distribution and fan-beam range of a multi-focal spot source of the ring of radiation sources shown in FIG. 1;
FIG. 3 is a schematic diagram of the arrangement of the transmission assembly and the support assembly in the front collimator according to the present invention;
FIG. 4 is a schematic structural diagram of a front collimator according to the present invention;
FIG. 5 is a schematic diagram of a drive assembly of the front collimator provided by the present invention;
fig. 6 is a schematic diagram of a beam limiting principle of the front collimator provided by the present invention;
FIG. 7 is a schematic diagram of a support assembly of a front collimator assembly according to the present invention;
FIG. 8 is a schematic view of the motion control of the front collimator provided by the present invention;
fig. 9 is a view showing an installation structure of a limit switch in the front collimator.
Detailed Description
The technical solution of the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
The utility model provides a preceding collimating device can be used to limit a bundle and shield invalid X scattered ray to the X ray bundle that the dense multifocal ray source of arranging sent in the radiation source ring among the static CT imaging system.
The static CT imaging system shown in fig. 1 includes a radiation source ring 1 and a detector ring 2 which are axially arranged in parallel, the radiation source ring 1 and the detector ring 2 are not in the same plane, and the radiation source ring 1 and the detector ring 2 are concentrically arranged. The radiation source ring 1 is composed of a plurality of X-ray sources 20 which are arranged in a ring shape closely, and the detector ring 2 is composed of a plurality of detectors 21 which are arranged in a ring shape closely; under the control of the scanning time sequence controller, each X-ray source 20 emits narrow-beam X-rays according to a scanning time sequence, the narrow-beam X-rays penetrate through the front collimating device and then penetrate through a measured object to be projected onto the corresponding detector 21, meanwhile, the scanning time sequence controller controls the corresponding detector 21 to carry out pixel acquisition, and pixel areas of other detectors are in an unresponsive state, so that the contribution of scattered rays to an effective acquisition area is greatly reduced. The detector 21 then feeds the corresponding exposure information to the CT mainframe for real-time reconstruction and visual reconstruction of the image.
Fig. 2 is a schematic diagram of a focal point distribution and ray ranges in the radiation source ring 1 shown in fig. 1, wherein the radiation source ring 1 includes a plurality of X-ray focal points 3 arranged densely, each of the X-ray focal points 3 emits a narrow beam of X-rays, the narrow beam of X-rays has an X-ray fan angle with an angle θ, and the X-ray ranges corresponding to the narrow beam of X-rays emitted by adjacent X-ray focal points 3 all have an overlap. As can be seen from the figure, in the radiation source ring 1 shown in fig. 1, a front collimator cannot be installed right in front of each single focus like the conventional spiral CT, otherwise the radiation range of the adjacent other focuses is blocked.
Therefore, the utility model provides a brand-new preceding collimating device with dicyclo structure, this preceding collimating device realizes restricting the beam and shielding the X ray that a plurality of focuses sent through suitable mounted position to it is adjustable to restrict the beam width, thereby restricts the bed thickness of beam width adjustment CT scanning through the adjustment. The slice thickness of a CT scan is an important indicator in clinical applications of CT.
As can be seen from fig. 3 to 7, the front collimating device for the static CT imaging system provided by the present invention includes a beam limiting inner ring 11 and a beam limiting outer ring 12, wherein the beam limiting inner ring 11 and the beam limiting outer ring 12 have the same diameter and are disposed between the radiation source ring 1 and the detector ring 2 in parallel, and the end surfaces of the beam limiting inner ring 11 and the beam limiting outer ring 12 are parallel. All the X-rays emitted by the focal points in the radiation source ring 1 within the fan angle theta can pass between the beam limiting inner ring 11 and the beam limiting outer ring 12, and the beam limiting inner ring 11 and the beam limiting outer ring 12 are used for limiting the width of the X-rays. The beam limiting outer ring 12 is fixedly arranged, the beam limiting outer ring 12 has a fine adjustment function, and the beam limiting outer ring 12 is fixed after being adjusted in place; the beam limiting inner ring 11 is movable relative to the beam limiting outer ring 12 to change the beam limiting width between the beam limiting inner ring 11 and the beam limiting outer ring 12. Fig. 6 is a schematic diagram showing that X-rays emitted by a single focus pass through between the beam limiting inner ring 11 and the beam limiting outer ring 12, and the beam limiting inner ring 11 and the beam limiting outer ring 12 respectively limit the widths of two sides of the X-rays, and the beam limiting width between the beam limiting inner ring 11 and the beam limiting outer ring 12 determines the scanning layer thickness.
The front collimating apparatus further includes at least two drive assemblies and a plurality of support assemblies. The plurality of transmission assemblies are used for simultaneously driving the beam limiting inner ring 11 to move corresponding to the beam limiting outer ring 12, and the plurality of support assemblies are used for providing stable support for the movement of the beam limiting inner ring 11. The number of the transmission assemblies and the supporting assemblies can be determined according to the number of the radiation source modules in the radiation source ring 1. The beam limiting inner ring 11 can move relative to the beam limiting outer ring 12 under the action of the transmission assembly and the support assembly, so that the beam limiting width between the beam limiting inner ring 11 and the beam limiting outer ring 12 is changed.
The arrangement of the transmission assembly and the support assembly will be described with reference to fig. 1 to 3, taking the radiation source ring 1 with 6 radiation source modules as an example. As shown in fig. 2, the densely arranged focal spots 3 in the radiation source ring 1 have several openings, the number of which depends on the structural design of the radiation source ring. Generally, the radiation source ring 1 is difficult to be made into a whole, the radiation source ring 1 is usually composed of several radiation source modules, which are screwed together, there is a mounting gap between two adjacent radiation source modules, and the transmission assembly and the support assembly are respectively disposed in the mounting gap between two adjacent radiation source modules in the radiation source ring 1. As shown in fig. 1, in the example given in this embodiment, the radiation source ring 1 is composed of six radiation source modules, the installation gap between adjacent radiation source modules is exactly the focal point vacancy position 5, and the transmission assembly and the support assembly are respectively disposed in 6 installation gaps in the radiation source ring 1. This position can be used as a mounting position for a threaded spindle in the transmission assembly or for an optical axis guide rail in the support assembly.
The following description will be given by taking the installation manner of 2 transmission assemblies and 4 support assemblies as an example. As shown in fig. 3, the first transmission assembly 13 and the second transmission assembly 14 are respectively disposed at two opposite focal point vacant positions 5, and the first support assembly 15, the second support assembly 16, the third support assembly 17 and the fourth support assembly 18 are respectively disposed at the remaining four focal point vacant positions 5, so that the two transmission assemblies in combination with the four support assemblies can provide stable driving and supporting for the inner ring 11 and the outer ring 12, so that the whole ring structure of the inner ring 11 can move synchronously.
The structure of the front collimator according to the present invention will be described in detail with reference to fig. 4 to 7. The front collimating device comprises a beam limiting inner ring 11, a beam limiting outer ring 12, an X-ray shielding inner ring 23, an X-ray shielding outer ring 24, a first transmission assembly 13, a second transmission assembly 14, a first supporting assembly 15, a second supporting assembly 16, a third supporting assembly 17 and a fourth supporting assembly 18.
The inner and outer restraint rings 11 and 12 are circular structures made of metal materials, the cross section of each restraint ring is L-shaped (see fig. 6), and a layer of lead sheet is respectively adhered on the inner sides of the restraint rings to increase the X-ray shielding capability. The X-ray shielding inner ring 23 is arranged between the beam limiting inner ring 11 and the detector ring 2 and is used for shielding scattered rays irradiated between the beam limiting inner ring 11 and the detector ring 2; an outer X-ray shield ring 24 is mounted on the support outer ring 6 for shielding scattered radiation impinging between the beam limiting outer ring 12 and the source ring 1. Thus, the inner ring 23 of the X-ray shield, the ring 2 of the detector, the ring 1 of the source of the radiation and the outer ring 24 of the X-ray shield form an enclosure of the X-rays, and the leakage of ineffective X-rays is prevented.
The first transmission assembly 13 and the second transmission assembly 14 have the same structure, and only the structure of one of the transmission assemblies will be described. As shown in fig. 5, the transmission assembly includes a motor 7 (including a motor driver and an encoder), a motor frame 27, a coupling 28, a lead screw 8 (such as a ball screw), a lead screw fixed end bearing seat 29, a lead screw floating end bearing seat 26, and a beam-limiting inner ring adapter 9. The lead screw floating end bearing block 26 is fixed on the detector support 10, the lead screw fixed end bearing block 29 is fixed on the support outer ring 6, the motor 7 is arranged on the outer side of the support outer ring 6 through a motor frame 27, the motor 7 is connected with the lead screw 8 through a coupler 28, and the lead screw 8 is provided with a beam-limiting inner ring adapter 9; the beam-limiting inner ring adapter 9 is coupled with the beam-limiting inner ring 11. As shown in fig. 6, when the motor 7 rotates, the motor 7 drives the screw 8 to rotate, and drives the beam limiting inner ring 11 to move relative to the beam limiting outer ring 12 through the beam limiting inner ring adaptor 9. The distance between the beam limiting inner ring 11 and the beam limiting outer ring 12 is the beam limiting width. The first transmission assembly 13 and the second transmission assembly 14 are symmetrically arranged on the circumference, and can simultaneously provide the same driving force for the whole circular ring structure of the restriction inner ring 11 to drive the whole circular ring to synchronously move.
The first support member 15, the second support member 16, the third support member 17 and the fourth support member 18 have the same structure, and only one of the support members is described herein. As shown in fig. 7, the support assembly includes an optical axis guide 30, an outer ring adapter support 31, and an inner ring movement adapter 32. One end of each of the four optical axis guide rails 30 is connected with the detector ring 2, and the other end is connected with the outer support ring 6, and the whole set of front collimation support structure is formed by the structure. The beam-limiting inner ring 11 is connected with the optical axis guide rail 30 through an inner ring movement adapter 32 and can freely move on the optical axis guide rail 30; the beam limiting outer ring 12 is connected with the optical axis guide rail 30 through an outer ring switching support 31, and the beam limiting outer ring 12 is fixed after being micro-adjusted to a proper position. When the first transmission assembly 13 and the second transmission assembly 14 drive the beam limiting inner ring 11 to move relative to the beam limiting outer ring 12, the beam limiting inner ring 11 drives the inner ring movement adaptor 32 to stably move along the optical axis guide rail 30, so that the whole circular ring structure of the beam limiting inner ring 11 is ensured to synchronously move relative to the beam limiting outer ring 12.
The structure of the front collimator is described above, and the control system of the front collimator is described below with reference to fig. 8.
The first transmission assembly 13 and the second transmission assembly 14 can be driven synchronously by the control system shown in fig. 8. The lead screw 8 is connected with the beam limiting inner ring 11 through the inner ring adapter 9, so that the beam limiting inner ring 11 can move back and forth, a gap formed between the beam limiting inner ring 11 and the beam limiting outer ring 12 after the beam limiting inner ring moves is the beam limiting width, fine adjustment of the beam limiting width can be achieved through accurate movement of the lead screw 8, and requirements of different scanning layer thicknesses are met.
The schematic diagram of the motion control of the pre-collimator is shown in fig. 8, and the motion control part is composed of a computer, a main controller, a motor driver, a motor 7, an encoder and a limit switch 35, wherein the motor driver, the motor 7, the encoder and the limit switch 35 are respectively provided with 2 groups. The computer is used for sending a motion control instruction and receiving the position of the encoder and the state of the limit switch; the main controller is used for realizing the motion control function of the front collimating device, and comprises a motion control instruction sent by a computer and a control pulse generated by a motor driver, counting the position pulse fed back by the encoder, detecting the state of a limit switch, and feeding back the position information to the computer; the motor driver is used for generating a driving voltage current signal of the stepping motor according to the received control pulse and the control direction; the motor 7 is used for driving the motion executing mechanism of the front collimating device to move under the control of the motor driver; the encoder is used for measuring the real-time position of the movement, outputting the measured real-time position to the main controller in the form of pulses, counting the pulses output by the encoder by the main controller and calculating an actual position value.
The structure diagram of the limit switch is shown in fig. 9, the limit switch 35 can be an infrared photoelectric switch, the position of the limit switch 35 mounted on the detector support 10 is fixed, the limit switch stopper 36 is mounted on the beam limiting inner ring 11, when the opening between the beam limiting inner ring 11 and the beam limiting outer ring 12 is the largest, the limit switch stopper 36 moves into the limit switch 35, the state of the photoelectric limit switch changes, and the main controller can detect the real-time state of the limit switch 35. The limit switch 35 has two functions, one is used as limit detection of the maximum opening position of the beam limiting inner ring 11 and the beam limiting outer ring 12, and the other is used as an encoder count value initial position correction switch.
The motion control process is as follows: after the system is powered on, the main controller controls the 2 motors 7 to move to the limit switches 35 to stop, the opening between the beam limiting inner ring 11 and the beam limiting outer ring 12 is the largest at the moment, when the main controller detects that the 2 limit switches 35 are in place, the count values of the 2 encoders are set as initial values respectively, and in the following movement control, the main controller performs addition and subtraction counting on the basis of the initial values. And after receiving a motion control instruction sent by the computer, the main controller synchronously controls the two motors 7 to move together, the moving speeds of the two motors 7 are the same as the total moving pulse number, and motion compensation is performed according to an actual count value fed back by the encoder, so that the beam limiting inner ring 11 and the beam limiting outer ring 12 are kept parallel when stopping.
The front collimator for the static CT imaging system provided by the present invention is introduced above. The utility model discloses provide simultaneously including above-mentioned preceding collimating device's static CT imaging system. For set up the collimator alone below every X ray source module, the utility model provides a preceding collimating device has a dicyclo structure, through limit a bundle inner ring and limit a bundle outer loop that set up the parallel between source ring and detector ring, limits a bundle to the X ray that the multifocal ray source that closely arranges sent from source ring for the X ray homoenergetic that adjacent focus sent passes through between limit a bundle inner ring and the limit a bundle outer loop, and can not lead to the fact the influence to the X ray of all source transmissions. Compared with the collimator arranged in front of a single ray source independently, the double-ring structure can avoid the obstruction of X rays emitted by the closely arranged multi-focus ray sources in the circumferential direction.
To sum up, the utility model provides a preceding collimating device for static CT imaging system comprises restraint inner ring and restraint outer loop, drives the restraint inner ring through drive screw and removes, can carry out continuous control to restraint the width to restraint between restraint inner ring and the restraint outer loop to adjust the bed thickness of CT scanning. The front collimating device with the double-ring structure is suitable for being used in a static CT imaging system with a whole-ring structure of a ray source and a detector, and is used for realizing beam limitation of X rays emitted by a multi-focus ray source and shielding of ineffective scattered rays. The front collimating device with the double-ring structure has the advantages of novel structure, good beam limiting adjustment and shielding effects on narrow-beam X-rays, simple structure and low cost. And, the utility model discloses provide the drive assembly and the supporting component of dicyclo structure simultaneously, two drive assemblies through synchronous movement have realized the synchronous movement of interior whole ring structure of restriction.
It is right above that the utility model provides a preceding collimating device for static CT imaging system and static CT imaging system thereof carried out detailed description. Any obvious modifications to the above would be obvious to those of ordinary skill in the art, without departing from the spirit of the present invention, and it is intended to constitute a violation of the patent rights of the present invention and to bear the relevant legal responsibility.
Claims (12)
1. A front collimation device for a static CT imaging system is characterized by comprising a beam limiting inner ring, a beam limiting outer ring, at least two transmission assemblies and a plurality of supporting assemblies;
the beam limiting inner ring and the beam limiting outer ring are arranged between the ray source ring and the detector ring in parallel; the beam limiting outer ring is fixedly arranged; the beam limiting inner ring can move relative to the beam limiting outer ring under the action of the transmission assembly and the support assembly, so that the beam limiting width between the beam limiting inner ring and the beam limiting outer ring is changed.
2. The pre-collimation apparatus for a static CT imaging system as recited in claim 1, wherein:
the transmission assembly comprises a motor, a motor frame, a coupler, a lead screw fixed end bearing seat, a lead screw floating end bearing seat and a beam-limiting inner ring adapter;
the lead screw floating end bearing block is fixed on the detector support, the lead screw fixed end bearing block is fixed on the support outer ring, the motor is arranged on the outer side of the support outer ring through the motor frame, the motor is connected with the lead screw through the coupler, and the lead screw is provided with the beam-limiting inner ring adapter; the beam-limiting inner ring adapter is connected with the beam-limiting inner ring;
when the motor rotates, the motor drives the screw rod to rotate, and the beam limiting inner ring is driven to move relative to the beam limiting outer ring through the beam limiting inner ring adapter.
3. The pre-collimation apparatus for a static CT imaging system as recited in claim 1, wherein:
the supporting assembly comprises an optical axis guide rail, an outer ring switching support and an inner ring moving switching piece; one end of the optical axis guide rail is connected with the detector ring, and the other end of the optical axis guide rail is connected with the support outer ring; the beam limiting inner ring is connected with the optical axis guide rail through the inner ring moving adapter and can freely move on the optical axis guide rail; the beam limiting outer ring is connected with the optical axis guide rail through an outer ring switching support, and the beam limiting outer ring is fixed.
4. The pre-collimation apparatus for a static CT imaging system as recited in claim 1, wherein:
the transmission assembly and the supporting assembly are respectively arranged in an installation gap between two adjacent ray source modules in the ray source ring.
5. The pre-collimation apparatus for a static CT imaging system as recited in claim 4, wherein:
the two transmission assemblies are symmetrically arranged in two opposite mounting gaps, and the plurality of supporting assemblies are respectively arranged in the rest mounting gaps.
6. The pre-collimation apparatus for a static CT imaging system as recited in claim 1, further comprising an X-ray shield inner ring mounted between the beam limiting inner ring and the detector ring and an X-ray shield outer ring mounted on a support outer ring.
7. The pre-collimation apparatus for a static CT imaging system as recited in claim 1, wherein:
the beam limiting inner ring and the beam limiting outer ring have the same diameter, and the end faces of the beam limiting inner ring and the beam limiting outer ring are parallel.
8. The pre-collimation apparatus for a static CT imaging system as recited in claim 1, wherein:
the inner beam limiting ring and the outer beam limiting ring are of circular structures made of metal materials respectively, the cross section of each circular structure is L-shaped, and a layer of lead sheet is pasted on the inner side of each circular structure.
9. The pre-collimation apparatus for a static CT imaging system as recited in claim 1, wherein:
and the two transmission assemblies realize synchronous driving through a control system.
10. The pre-collimation apparatus for a static CT imaging system as recited in claim 9, wherein:
the control system comprises a computer, a main controller, a motor driver, a motor, an encoder and a limit switch, wherein the motor driver, the motor, the encoder and the limit switch are respectively provided with 2 groups.
11. The pre-collimation apparatus for a static CT imaging system as recited in claim 10, wherein:
the limit switch is an infrared photoelectric switch, is arranged on the detector bracket and is fixed in position; and the limit switch stop block is arranged on the beam limiting inner ring.
12. A static CT imaging system comprising a source ring and a detector ring arranged axially in parallel, characterized by further comprising a pre-collimation device as claimed in any one of claims 1 to 11;
the radiation source ring consists of a plurality of X-ray sources which are closely arranged into a ring shape, and the detector ring consists of a plurality of detectors which are closely arranged into a ring shape;
under the control of the scanning time sequence controller, each X-ray source emits X-rays according to a scanning time sequence, and the X-rays irradiate the corresponding detector after passing through the front collimating device.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2019201519061 | 2019-01-29 | ||
| CN201910084890 | 2019-01-29 | ||
| CN2019100848901 | 2019-01-29 | ||
| CN201920151906 | 2019-01-29 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209863859U true CN209863859U (en) | 2019-12-31 |
Family
ID=66196684
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920223101.3U Active CN209863859U (en) | 2019-01-29 | 2019-02-22 | Front collimation device for static CT imaging system and static CT imaging system thereof |
| CN201910131701.1A Pending CN109674486A (en) | 2019-01-29 | 2019-02-22 | Preceding collimator apparatus and its static state CT imaging system for static CT imaging system |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910131701.1A Pending CN109674486A (en) | 2019-01-29 | 2019-02-22 | Preceding collimator apparatus and its static state CT imaging system for static CT imaging system |
Country Status (1)
| Country | Link |
|---|---|
| CN (2) | CN209863859U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109674486A (en) * | 2019-01-29 | 2019-04-26 | 北京纳米维景科技有限公司 | Preceding collimator apparatus and its static state CT imaging system for static CT imaging system |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5493599A (en) * | 1992-04-03 | 1996-02-20 | Picker International, Inc. | Off-focal radiation limiting precollimator and adjustable ring collimator for x-ray CT scanners |
| US5442673A (en) * | 1994-03-30 | 1995-08-15 | Siemens Aktiengesellschaft | Fixed septum collimator for electron beam tomography |
| CN100574827C (en) * | 2005-08-25 | 2009-12-30 | 深圳市海博科技有限公司 | Radiotherapy unit |
| US8897413B2 (en) * | 2008-05-21 | 2014-11-25 | Koninklijke Philips N.V. | Dynamic adjustable source collimation during fly-by scanning |
| US8637841B2 (en) * | 2010-08-23 | 2014-01-28 | Varian Medical Systems, Inc. | Multi level multileaf collimators |
| CN102688558B (en) * | 2012-05-29 | 2015-06-03 | 武汉数码刀医疗有限公司 | Radiation therapy equipment |
| CN102783960A (en) * | 2012-08-24 | 2012-11-21 | 北京东方惠尔图像技术有限公司 | Beam limitation adjusting device and beam limitation adjusting method of rays and imaging device |
| CN104684482B (en) * | 2012-10-01 | 2019-02-12 | 东芝医疗系统株式会社 | Image processing apparatus and X ray CT device |
| CN103839603B (en) * | 2012-11-27 | 2017-12-22 | Ge医疗系统环球技术有限公司 | CT collimators and the CT system for including the CT collimators |
| CN103337272B (en) * | 2013-06-27 | 2016-02-03 | 东软飞利浦医疗设备系统有限责任公司 | X-ray collimator and collimation thereof crack width adjustment method |
| CN209863859U (en) * | 2019-01-29 | 2019-12-31 | 北京纳米维景科技有限公司 | Front collimation device for static CT imaging system and static CT imaging system thereof |
-
2019
- 2019-02-22 CN CN201920223101.3U patent/CN209863859U/en active Active
- 2019-02-22 CN CN201910131701.1A patent/CN109674486A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109674486A (en) * | 2019-01-29 | 2019-04-26 | 北京纳米维景科技有限公司 | Preceding collimator apparatus and its static state CT imaging system for static CT imaging system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109674486A (en) | 2019-04-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| AU654621B2 (en) | Improved X-ray volumetric CT scanner | |
| US9579075B2 (en) | Detector array comprising energy integrating and photon counting cells | |
| CN1192746C (en) | Operating method of CT machine and CT machine | |
| US9724056B2 (en) | Method and system for spectral computed tomography (CT) with inner ring geometry | |
| US7170975B2 (en) | Method for operating a computed tomography apparatus having a diaphragm at the radiation detector | |
| US8094775B2 (en) | X-ray computer tomography apparatus including a pair of separably movable collimators | |
| KR101181939B1 (en) | Method and device for collimating an energy input beam | |
| US20150282778A1 (en) | X-ray ct apparatus and controlling method | |
| JP5559875B2 (en) | Multi-detector array imaging system | |
| US9087619B2 (en) | Apparatus for scatter reduction for CT imaging and method of fabricating same | |
| EP2822467B1 (en) | X-ray beam shaper | |
| US10314553B2 (en) | Focal spot position control using pre-patient collimator with beam tracking | |
| EP2648620B1 (en) | Post-patient dynamic filter for computed tomography (ct) | |
| CN209863859U (en) | Front collimation device for static CT imaging system and static CT imaging system thereof | |
| JP2009066403A (en) | Computerized tomography system and apparatus | |
| US10799193B2 (en) | Method and apparatus for anatomically-specified conformation computed tomography | |
| JP2007282740A (en) | X-ray ct apparatus | |
| JP2007319496A (en) | Control device for radiotherapy system and radiation irradiation method | |
| JP3265035B2 (en) | Computer tomography equipment | |
| US4277687A (en) | Tomographic apparatus for producing transverse layer images | |
| JPH04297241A (en) | X-ray ct system | |
| JP2009297577A (en) | X-ray computed tomography scanner |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |