CN116671951A - Focus adjustment system and method for static CT - Google Patents
Focus adjustment system and method for static CT Download PDFInfo
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- 238000004364 calculation method Methods 0.000 description 1
- 238000002591 computed tomography Methods 0.000 description 1
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- A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
- A61B6/02—Arrangements for diagnosis sequentially in different planes; Stereoscopic radiation diagnosis
- A61B6/03—Computed tomography [CT]
- A61B6/032—Transmission computed tomography [CT]
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- A61B6/4007—Arrangements for generating radiation specially adapted for radiation diagnosis characterised by using a plurality of source units
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- A61B6/42—Arrangements for detecting radiation specially adapted for radiation diagnosis
- A61B6/4266—Arrangements for detecting radiation specially adapted for radiation diagnosis characterised by using a plurality of detector units
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- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
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- A61B6/588—Setting distance between source unit and detector unit
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Abstract
The invention discloses a focus adjusting system and a focus adjusting method for static CT. The focus adjustment system includes: the radiation source support is arranged on the frame and is provided with a radiation source ring, and the radiation source ring is surrounded by a plurality of radiation sources to form a circular ring; the detector ring is arranged on the ray source bracket; the imaging object support is arranged on one side of the ray source support and provided with an imaging object ring, the imaging object ring is surrounded by a plurality of imaging objects to form a circular ring, and the imaging objects are in one-to-one correspondence with the ray sources; the focal point adjusting part comprises a plurality of focal point adjusting units which are respectively and correspondingly connected with the plurality of ray sources so as to respectively drive the corresponding ray sources to reciprocate; the controller is arranged on the frame and used for performing exposure control on the plurality of ray sources; the focus offset of each ray source is calculated; and also for controlling the movement of the focus adjustment units to adjust the focus position of the respective radiation sources. By using the invention, the geometric relationship between the theoretical focal position and the detector can be ensured to be accurate.
Description
Technical Field
The invention relates to a focus adjusting system of static CT, and also relates to a corresponding focus adjusting method, belonging to the technical field of computer tomography.
Background
The radiation source of static CT is formed from several radiation sources, and is distributed in the form of circular ring. The focal position of each ray source is required to be coplanar on the XY plane, and because the ray source die has an error of about +/-1.5 mm during manufacturing, the ray source focal point of the static CT after installation can have larger deviation, the geometric relationship between the ray source and components such as a beam limiter, a detector and the like is influenced, and accurate calibration operation on the static CT is not easy to perform.
The coincidence of the source focus with the detector at the theoretical center directly affects the quality of the reconstructed image. In some cases, the number of radiation sources of static CT can be up to 24, so that the focus of each radiation source is coincident with the detector in the theoretical center, and the error is controlled within +/-1 pixel.
In the Chinese patent with patent number ZL 201711121001.1, a geometric calibration device of a static cone beam CT imaging system is disclosed. The device comprises a plurality of cold cathode X-ray tubes which are arranged in a linear or arc shape to form a multi-beam X-ray source array, wherein each cold cathode X-ray tube is used as an X-ray emission source; the support frame reserves the regulation space on X, Y and Z axle to make a plurality of cold cathode X-ray tube install on the support frame after, every cold cathode X-ray tube position can realize adjusting respectively in X, Y or three directions of Z axle. By adjusting each cold cathode X-ray tube in three directions of X, Y or Z axis, the geometric position of each X-ray source is accurately calibrated, and the calibration precision is extremely high.
However, in the above technical solution, although the position of each X-ray source can be adjusted, the focus offset of each X-ray source in the static CT system cannot be found, so that the physical adjustment after the focus offset of the static CT system is difficult to be realized, and further, the geometric relationship between the theoretical focus position and the detector cannot be ensured to be accurate.
Disclosure of Invention
The primary technical problem to be solved by the invention is to provide a focus adjusting system of static CT.
Another technical problem to be solved by the present invention is to provide a focus adjustment method for static CT.
In order to achieve the technical purpose, the invention adopts the following technical scheme:
according to a first aspect of an embodiment of the present invention, there is provided a focal point adjustment system of a static CT, including:
the radiation source support is arranged on the frame, a radiation source ring is arranged on the radiation source support, and the radiation source ring is surrounded by a plurality of radiation sources to form a circular ring;
the detector ring is arranged on the ray source bracket, and the axis of the detector ring is coincident with the axis of the ray source ring;
the imaging object support is arranged on one side of the ray source support, an imaging object ring is arranged on the imaging object support, the imaging object ring is surrounded by a plurality of imaging objects to form a circular ring shape, and the axis of the imaging object ring is overlapped with the axis of the detector ring; the imaging objects are in one-to-one correspondence with the radiation sources, so that each radiation source can emit X rays towards the corresponding imaging object and form a projection image on the detector ring;
the focal point adjusting part comprises a plurality of focal point adjusting units, the focal point adjusting units are respectively and correspondingly connected with the ray sources, and each focal point adjusting unit respectively drives the corresponding ray source to reciprocate along the axis direction of the detector ring;
the controller is arranged on the rack and is electrically connected with the plurality of ray sources so as to perform exposure control on the plurality of ray sources; the controller is also electrically connected with the detector ring to calculate focus offset of each ray source based on projection images of the detector ring; the controller is also electrically connected with the focus adjustment part, so as to control each focus adjustment unit to drive the corresponding ray source to move along the axis direction of the detector ring based on the focus offset of each ray source, thereby respectively adjusting the focus position of each ray source.
Wherein preferably, the focus offset of each ray source is calculated based on the projection image of the detector ring, and specifically comprises:
determining coordinates of actual pixel points of each ray source in a preset space coordinate system according to the projection image of the detector ring; the preset space coordinate system is constructed by taking a theoretical focus as an origin, taking the axial direction of the detector ring as a Z axis, taking the horizontal direction which is perpendicular to the Z axis and passes through the origin as an X axis and taking the vertical direction which is perpendicular to the Z axis and passes through the origin as a Y axis;
the focus offset Z of each ray source is calculated according to the following formula Offset of deflection ；
Z Offset of deflection = (actual pixel-theoretical pixel)/(SID-SOD) SOD pixel size;
the detector ring consists of a plurality of pixel points, and each pixel point has corresponding coordinates in a preset space coordinate system; SID denotes the size of the source focus to the detector surface; SOD represents the radial dimension of the focal ring of the source.
Preferably, the focus adjusting unit specifically includes:
the adjusting seat is arranged on the ray source bracket;
the adjusting screw is arranged on the adjusting seat and is fixedly connected with the ray source, the axial direction of the adjusting screw is parallel to the axial direction of the detector ring, and the ray source can be driven to reciprocate along the axial direction of the detector ring by rotating the adjusting screw.
Wherein preferably the imaging subject ring comprises a plurality of T-shaped prisms and a light transmissive ring;
the T-shaped prisms are uniformly arranged on one side, facing the ray source support, of the imaging object support around the axis of the ray source support, and are jointly enclosed into a ring shape, and the T-shaped prisms are respectively in one-to-one correspondence with the ray sources; the light-transmitting ring is arranged on one side, far away from the imaging object support, of the T-shaped prisms, and is used for transmitting X rays.
Wherein preferably, the radiation source bracket is provided with a waist-shaped hole, and the length direction of the waist-shaped hole is parallel to the axis direction of the detector ring;
the frame is provided with a guide pin which is arranged in the waist-shaped hole so that the ray source bracket and the frame can move relatively in the moving range of the waist-shaped hole, to adjust the position of the source holder in the direction of the detector ring axis.
Wherein preferably the imaging subject support is removably mounted to one side of the source support.
Preferably, a positioning groove is formed in one side of the ray source support, a positioning column is arranged on one side of the imaging object support, which faces the ray source support, and the positioning column is inserted into or separated from the positioning groove.
According to a second aspect of the embodiment of the present invention, there is provided a focus adjustment method of static CT, including the steps of:
exposing through the ray source ring to enable each ray source to emit X rays towards a corresponding imaging object respectively, and forming a projection image on the detector ring;
collecting projection images of all the ray sources through the detector ring;
the projection images of the ray sources are acquired through a controller, and the projection offset of the ray sources is calculated respectively;
respectively judging whether the projection offset of each ray source exceeds a preset reasonable deviation range;
if the focus is not exceeded, the focus is not required to be adjusted; if the projection images of the regulated ray sources are not more than the preset reasonable deviation range, the controller controls the focus regulating part to drive each ray source to be regulated to move along the axis direction of the detector ring according to the focus deviation amount of each ray source to be regulated so as to regulate the focus, and after the focus is regulated, the regulated ray sources are used for exposure again so as to collect the projection images of the regulated ray sources again, and the projection deviation amounts of all the ray sources do not exceed the preset reasonable deviation range.
Preferably, the exposing mode of the ray source ring at least comprises:
exposing the plurality of ray sources one by one according to a preset sequence; or at least two ray sources are exposed simultaneously, and the exposure is performed sequentially according to a preset sequence;
wherein the projection images of at least two radiation sources exposed simultaneously do not overlap each other.
Wherein preferably, before the radiation source ring is exposed, the imaging object support provided with the imaging object ring is arranged on the radiation source support in advance; and after the focal point is adjusted, the imaging object support provided with the imaging object ring is detached from the ray source support.
Compared with the prior art, the invention has the following technical effects:
1. the accurate system focus offset position of the static CT can be found, physical adjustment is further achieved, and the coplanarity of a plurality of ray sources in an XY plane is achieved, so that the geometric relationship between the theoretical focus position and the detector is ensured to be accurate.
2. The imaging object rings are arranged so that a plurality of imaging objects are respectively in one-to-one correspondence with a plurality of ray sources, and focus adjustment is carried out on each ray source respectively. And the imaging object ring can be detached for recycling.
3. The Z-axis center of the detector ring is used as a focus theoretical projection position, and the detector ring is not required to be adjusted in the Z-axis direction, so that the convenience of installation and fixation of the detector ring is improved.
Drawings
FIG. 1 is a schematic view of a focal point adjustment system of a static CT according to a first embodiment of the present invention;
FIG. 2 is a schematic view of the structure of FIG. 1 at another angle;
FIG. 3 is a schematic view showing a combined structure of a gantry and a source of radiation in a first embodiment of the present invention;
FIG. 4 is a schematic diagram showing a combined structure of an object holder and an object ring according to a first embodiment of the present invention;
fig. 5 is a flowchart of a focus adjustment method for static CT according to a second embodiment of the present invention.
Detailed Description
The technical contents of the present invention will be described in detail with reference to the accompanying drawings and specific examples.
First embodiment
As shown in fig. 1 to 3, a focal point adjusting system for static CT according to a first embodiment of the present invention includes a gantry 10, a source support 1, a detector ring 2, an object support 3, an object ring 4, a focal point adjusting portion 5, and a controller.
In particular, the source holder 1 comprises a base 11 and an annular body 12. The base 11 is mounted on the frame 10, and a waist-shaped hole 111 is formed in the base 11, and the length direction of the waist-shaped hole 111 is parallel to the axis direction of the annular main body 12. The gantry 10 is provided with a guide pin 110, and the guide pin 110 is disposed in the waist-shaped hole 111, so that the radiation source support 1 and the gantry 10 can relatively move within the movement range of the waist-shaped hole 111, so as to adjust the position of the radiation source support 1 in the axial direction of the annular main body 12. The ring-shaped body 12 is provided with a plurality of radiation sources 101, and the plurality of radiation sources 101 are arranged in a circular shape around the axis direction of the ring-shaped body 12.
The detector ring 2 is attached to the inner ring surface of the ring body 12, and the axis of the detector ring 2 coincides with the axis of the radiation source ring for image detection.
As shown in fig. 4, the imaging material holder 3 is mounted on one side of the radiation source holder 1. And, one side of the imaging object support 3 facing the radiation source support 1 is provided with a positioning column 31, and correspondingly, one side of the radiation source support 1 is provided with a positioning groove, and the positioning column 31 is inserted into or separated from the positioning groove so as to detachably mount the imaging object support 3 on the radiation source support 1. The imager support 3 has an imager ring 4 mounted thereon, and as shown with reference to fig. 4, the imager ring 4 includes a plurality of T-shaped prisms 41 and a light transmissive ring 42. Wherein, the T-shaped prism 41 is made of metal material, a plurality of T-shaped prisms 41 are uniformly arranged on one side of the imaging object bracket 3 facing the ray source bracket 1 around the axis of the detector ring 2 and are jointly enclosed into a circular ring shape; the plurality of T-shaped prisms 41 are in one-to-one correspondence with the plurality of radiation sources 101, respectively. The light-transmitting ring 42 is annular and made of a material with higher light transmittance, and the light-transmitting ring 42 is arranged on one side of the plurality of T-shaped prisms 41 far away from the imaging object support 3 for transmitting X rays and supporting the plurality of T-shaped prisms, so that the plurality of T-shaped prisms are uniformly arranged in the light-transmitting ring 42. It will be appreciated that in one embodiment of the invention, a plurality of imaging subjects can be formed using a plurality of T-prisms 41 in combination with a light transmissive ring 42, and the plurality of imaging subjects are in one-to-one correspondence with the plurality of radiation sources 101 such that each radiation source 101 is capable of emitting X-rays toward the corresponding imaging subject and forming a projection image on the detector ring 2.
In this embodiment, the focal point adjusting portion 5 includes a plurality of focal point adjusting units 51, where the plurality of focal point adjusting units 51 are respectively connected to the plurality of radiation sources 101, and each focal point adjusting unit 51 drives the corresponding radiation source 101 to reciprocate along the axis direction of the detector ring 2, so as to implement focal point adjustment for each radiation source 101. As shown in fig. 3, in the present embodiment, the focus adjustment unit 51 includes an adjustment seat 511 and an adjustment screw 512, wherein the adjustment seat 511 is disposed on the radiation source holder 1; the adjusting screw 512 is mounted on the adjusting seat 511 and is fixedly connected with the radiation source 101, the axial direction of the adjusting screw 511 is parallel to the axial direction of the detector ring 2, and the radiation source 101 can be driven to reciprocate along the axial direction of the detector ring 2 by rotating the adjusting screw 512, so that the focus adjustment of the radiation source 101 is realized. Furthermore, in one embodiment of the present invention, the adjustment screw 511 is displaced by 0.5mm per rotation and 0.05mm per rotation of the cell, and the adjustment is specifically made according to the actual offset position of the focal spot of each radiation source 101.
A controller is provided on the gantry 10, and the controller is electrically connected to the plurality of radiation sources 101 to perform exposure control on the plurality of radiation sources 101. The controller is also electrically connected to the detector ring 2 to calculate the focus offset of each of the radiation sources 101 based on the projection image of the detector ring 2 according to a predetermined algorithm program. The controller is further electrically connected to the focus adjustment unit 5 to control each of the focus adjustment units 51 to move the corresponding radiation source 101 in the axial direction of the detector ring 2 based on the focus offset amount of each of the radiation sources 101, thereby adjusting the focus position of each of the radiation sources 101, respectively.
In the above-described embodiment, the focus offset calculation of each radiation source is performed by:
firstly, determining coordinates of actual pixel points of each ray source 101 in a preset space coordinate system according to projection images of the detector ring 2; the preset space coordinate system is constructed by taking a theoretical focus as an origin, taking the axial direction of the detector ring 2 as a Z axis, taking the horizontal direction which is perpendicular to the Z axis and passes through the origin as an X axis, and taking the vertical direction which is perpendicular to the Z axis and passes through the origin as a Y axis. Then, the focus offset amount zoffset of each of the radiation sources 101 is calculated according to the following formula.
Z-bias= (actual pixel-theoretical pixel)/(SID-SOD) SOD pixel size;
the detector ring consists of a plurality of pixel points, and each pixel point has corresponding coordinates in a preset space coordinate system; SID denotes the size of the source focus to the detector surface; SOD represents the radial dimension of the focal ring of the source.
It can be understood that when the focus adjustment system is specifically used, firstly, the center point of each projection image is found by importing the projection image into a preset algorithm program; then, looking at the pixel position of the center point on the detector ring 2, and finding the offset position of each ray source 101 by using a formula; finally, the radiation source focus is adjusted to the theoretical correct position by finding the accurate radiation source focus offset position. Therefore, by finding the accurate system focus offset position of the static CT, physical adjustment is realized, and the coplanarity of a plurality of ray sources in an XY plane is realized, so that the geometric relationship between the theoretical focus position and the detector 2 is ensured to be accurate.
Second embodiment
As shown in fig. 5, on the basis of the first embodiment, a second embodiment of the present invention further provides a focal point adjusting method of static CT, which specifically includes steps S1 to S5:
s1: the radiation source 101 is exposed.
Specifically, exposure is performed by the radiation source ring so that each radiation source 101 emits X-rays toward the corresponding imaging object, respectively, and a projection image is formed on the detector ring 2. In this embodiment, the exposure mode of the radiation source ring at least includes: the plurality of radiation sources 101 are exposed one by one according to a preset sequence; or at least two ray sources are exposed simultaneously, and the exposure is performed sequentially according to a preset sequence; wherein the projection images of at least two radiation sources 101 exposed simultaneously do not overlap each other.
S2: projection images of the individual radiation sources 101 are acquired by the detector ring 2.
S3: the projection offset of each radiation source 101 is calculated.
Specifically, the controller acquires projection images of the respective radiation sources 101 to find the center point of each projection image; the pixel locations of the center points on the detector ring 2 are then examined and the projection offset for each source 101 is found using the above formula.
S4: it is determined whether the projection offset of each of the radiation sources 101 exceeds a preset reasonable deviation range, respectively.
Specifically, if the projection offset of the radiation source 101 does not exceed the preset reasonable deviation range, the focus adjustment is not required. Otherwise, if the radiation source to be adjusted exceeds the preset value, the controller controls the focus adjusting part 5 to drive each radiation source 101 to be adjusted to move along the axis direction of the detector ring 2 according to the focus offset of each radiation source 101 to be adjusted so as to perform focus adjustment. And, after the focus adjustment is completed, exposure is performed again by the adjusted ray source 101 to re-acquire the projection images of the adjusted ray source 101 until the projection offset of all ray sources 101 does not exceed the preset reasonable deviation range.
S5: the imaging object holder 3 is removed.
Specifically, before the exposure of the radiation source ring, the imaging material support 3 provided with the imaging material ring 4 is mounted on the radiation source support 1 in advance. When the focal spot adjustment is completed, the imaging object holder 3 provided with the imaging object ring 4 is detached from the radiation source holder 1. So that the imaging subject support 3 provided with the imaging subject ring 4 can be reused for focus adjustment of other stationary CT systems.
In summary, the system and the method for adjusting the focus of the static CT provided by the embodiment of the invention have the following beneficial effects:
1. the accurate system focus offset position of the static CT can be found, physical adjustment is further achieved, and the coplanarity of a plurality of ray sources in an XY plane is achieved, so that the geometric relationship between the theoretical focus position and the detector is ensured to be accurate.
2. The imaging object rings are arranged so that a plurality of imaging objects are respectively in one-to-one correspondence with a plurality of ray sources, and focus adjustment is carried out on each ray source respectively. And the imaging object ring can be detached for recycling.
3. The Z-axis center of the detector ring is used as a focus theoretical projection position, and the detector ring is not required to be adjusted in the Z-axis direction, so that the convenience of installation and fixation of the detector ring is improved.
The focus adjustment system and method for static CT provided by the invention are described in detail above. Any obvious modifications to the present invention, without departing from the spirit thereof, would constitute an infringement of the patent rights of the invention and would take on corresponding legal liabilities.
Claims (10)
1. A focal point adjustment system for static CT, comprising:
the radiation source support is arranged on the frame, a radiation source ring is arranged on the radiation source support, and the radiation source ring is surrounded by a plurality of radiation sources to form a circular ring;
the detector ring is arranged on the ray source bracket, and the axis of the detector ring is coincident with the axis of the ray source ring;
the imaging object support is arranged on one side of the ray source support, an imaging object ring is arranged on the imaging object support, the imaging object ring is surrounded by a plurality of imaging objects to form a circular ring shape, and the axis of the imaging object ring is overlapped with the axis of the detector ring; the imaging objects are in one-to-one correspondence with the radiation sources, so that each radiation source can emit X rays towards the corresponding imaging object and form a projection image on the detector ring;
the focal point adjusting part comprises a plurality of focal point adjusting units, the focal point adjusting units are respectively and correspondingly connected with the ray sources, and each focal point adjusting unit respectively drives the corresponding ray source to reciprocate along the axis direction of the detector ring;
the controller is arranged on the rack and is electrically connected with the plurality of ray sources so as to perform exposure control on the plurality of ray sources; the controller is also electrically connected with the detector ring to calculate focus offset of each ray source based on projection images of the detector ring; the controller is also electrically connected with the focus adjustment part, so as to control each focus adjustment unit to drive the corresponding ray source to move along the axis direction of the detector ring based on the focus offset of each ray source, thereby respectively adjusting the focus position of each ray source.
2. The focus adjustment system of claim 1, wherein said calculating a focus offset for each radiation source based on projection images of said detector ring, comprises:
determining coordinates of actual pixel points of each ray source in a preset space coordinate system according to the projection image of the detector ring; the preset space coordinate system is constructed by taking a theoretical focus as an origin, taking the axial direction of the detector ring as a Z axis, taking the horizontal direction which is perpendicular to the Z axis and passes through the origin as an X axis and taking the vertical direction which is perpendicular to the Z axis and passes through the origin as a Y axis;
calculating the focus offset Z offset of each ray source according to the following formula;
z-bias= (actual pixel-theoretical pixel)/(SID-SOD) SOD pixel size;
the detector ring consists of a plurality of pixel points, and each pixel point has corresponding coordinates in a preset space coordinate system; SID denotes the size of the source focus to the detector surface; SOD represents the radial dimension of the focal ring of the source.
3. The focus adjustment system according to claim 1, characterized in that the focus adjustment unit comprises in particular:
the adjusting seat is arranged on the ray source bracket;
the adjusting screw is arranged on the adjusting seat and is fixedly connected with the ray source, the axial direction of the adjusting screw is parallel to the axial direction of the detector ring, and the ray source can be driven to reciprocate along the axial direction of the detector ring by rotating the adjusting screw.
4. The focal length adjustment system of claim 1, wherein the imager ring comprises a plurality of T-shaped prisms and a light transmissive ring;
the T-shaped prisms are uniformly arranged on one side, facing the ray source support, of the imaging object support around the axis of the ray source support, and are jointly enclosed into a ring shape, and the T-shaped prisms are respectively in one-to-one correspondence with the ray sources; the light-transmitting ring is arranged on one side, far away from the imaging object support, of the T-shaped prisms so as to transmit X rays.
5. The focal length adjustment system of claim 1, wherein:
the radiation source bracket is provided with a waist-shaped hole, and the length direction of the waist-shaped hole is parallel to the axis direction of the detector ring;
the frame is provided with a guide pin which is arranged in the waist-shaped hole so that the ray source bracket and the frame can move relatively in the moving range of the waist-shaped hole, to adjust the position of the source holder in the direction of the detector ring axis.
6. The focal length adjustment system of claim 1, wherein:
the imaging object support is detachably mounted on one side of the radiation source support.
7. The focal length adjustment system of claim 6, wherein:
a positioning groove is formed in one side of the ray source support, a positioning column is arranged on one side, facing the ray source support, of the imaging object support, and the positioning column is inserted into or separated from the positioning groove.
8. A focus adjustment method for static CT, comprising the steps of:
exposing through the ray source ring to enable each ray source to emit X rays towards a corresponding imaging object respectively, and forming a projection image on the detector ring;
collecting projection images of all the ray sources through the detector ring;
the projection images of the ray sources are acquired through a controller, and the projection offset of the ray sources is calculated respectively;
respectively judging whether the projection offset of each ray source exceeds a preset reasonable deviation range;
if the focus is not exceeded, the focus is not required to be adjusted; if the projection images of the regulated ray sources are not more than the preset reasonable deviation range, the controller controls the focus regulating part to drive each ray source to be regulated to move along the axis direction of the detector ring according to the focus deviation amount of each ray source to be regulated so as to regulate the focus, and after the focus is regulated, the regulated ray sources are used for exposure again so as to collect the projection images of the regulated ray sources again, and the projection deviation amounts of all the ray sources do not exceed the preset reasonable deviation range.
9. The focus adjustment method according to claim 8, wherein the exposure mode of the radiation source ring at least includes:
exposing the plurality of ray sources one by one according to a preset sequence; or at least two ray sources are exposed simultaneously, and the exposure is performed sequentially according to a preset sequence;
wherein the projection images of at least two radiation sources exposed simultaneously do not overlap each other.
10. A focus adjustment method as claimed in claim 8, characterized in that:
before the radiation source ring is exposed, an imaging object bracket provided with an imaging object ring is arranged on the radiation source bracket in advance; and after the focal point is adjusted, the imaging object support provided with the imaging object ring is detached from the ray source support.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310795784.0A CN116671951A (en) | 2023-06-30 | 2023-06-30 | Focus adjustment system and method for static CT |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310795784.0A CN116671951A (en) | 2023-06-30 | 2023-06-30 | Focus adjustment system and method for static CT |
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