CN116990854A - CT system and security inspection equipment - Google Patents

Abstract

The invention relates to the technical field of CT imaging equipment, and discloses a CT system and security inspection equipment. The CT system includes a rectangular channel extending along the Z direction, a rotating component, a ray source and a detector component. The detector assembly includes a middle detector and an edge detector. The rays from the ray source pass through the rectangular channel and are irradiated on the detector assembly. When the turret rotates 360 degrees, a ring edge of the rectangular channel is formed between the ray source and the edge detector. Detection area, the overlapping part of the annular edge detection area and the rectangular channel is not larger than the non-overlapping part of the annular edge detection area and the rectangular channel; the row number of the crystal modules on the first sub-edge detector and the second sub-edge detector is the middle detection Half the number of rows of crystal modules on the detector; the crystal modules of the first sub-edge detector and the crystal modules of the second sub-edge detector are staggered along the Z direction without overlapping positions.

Description

A CT system and security inspection equipment

Technical field

The present invention relates to the technical field of CT imaging equipment, and in particular, to a CT system and security inspection equipment.

Background technique

At present, the CT (Computed Tomography) system consists of a radiation source, a detector, a rotor, a data transmission system, a computer, a rack, and a transmission system. The ray source and detector are both mounted on the rotor and rotate together. The object to be detected is placed on the conveyor belt and transmitted along the Z-axis direction. The ray source emits X-rays. After the X-rays pass through the object to be inspected, the remaining rays are received by the detector. The data received by the detector is transmitted to the computer through the wireless data transmission system. The computer processes the data and analyzes the internal density of the object to be inspected and other information. , finally forming a CT image. The ray source and detector continuously rotate around the object to be detected, irradiate the object from different angles and receive the remaining X-rays. The data received by the detector is transmitted to the computer through a wireless data transmission system. The computer processes the data, analyzes the shape and atomic number of the detected object, and finally forms a CT image of the detected object.

In the prior art, the edge detector affects the rotation radius. In order to reduce the size of the CT system, the edge detector is moved toward the radiation source, thereby reducing the maximum rotation radius of the gantry. However, when the edge detector moves toward the ray source, the edge detector needs to become proportionally smaller along the Z-axis direction. Therefore, the crystal row spacing of the edge detector must become smaller to meet conventional algorithms and performance requirements. However, as the row spacing becomes smaller, the manufacturing difficulty of the detector increases, which will increase the cost, and even the current technical level cannot meet the processing of edge detectors.

Based on this, there is an urgent need for a CT system and security inspection equipment to solve the above existing problems.

Contents of the invention

Based on the above, the purpose of the present invention is to provide a CT system and security inspection equipment to reduce the processing difficulty of the first sub-edge detector and the second sub-edge detector, thereby reducing production costs.

In order to achieve the above objects, the present invention adopts the following technical solutions:

On the one hand, a CT system is provided, including:

A rectangular channel extending along the Z direction;

A rotating assembly, which includes a rotating frame, the rotating frame is ringed in the rectangular channel;

A ray source and a detector assembly, the ray source and the detector assembly are both mounted on the turret, and the ray source and the detector assembly are arranged on both sides of the rectangular channel;

The detector assembly includes a middle detector and an edge detector. The edge detector includes a first sub-edge detector and a second sub-edge detector symmetrically arranged on both sides of the middle detector. The ray source The rays pass through the rectangular channel and are irradiated on the detector assembly. When the turret rotates 360 degrees, an annular edge detection area for detecting the rectangular channel is formed between the ray source and the edge detector. The overlapping portion of the annular edge detection area and the rectangular channel is no larger than the non-overlapping portion of the annular edge detection area and the rectangular channel;

The middle detector, the first sub-edge detector and the second sub-edge detector are all provided with multiple rows of crystal modules evenly spaced along the Z direction. The crystal modules on the first sub-edge detector The number of rows is the same as the number of rows of crystal modules on the second sub-edge detector, and the number of rows of crystal modules on the first sub-edge detector is the number of rows of crystal modules on the middle detector half of;

The crystal module of the first sub-edge detector and the crystal module of the second sub-edge detector are staggered along the Z direction without overlapping positions.

As a preferred technical solution of the CT system, the middle detector is arranged on the first arc surface, the edge detector is arranged on the second arc surface, the first arc surface and the second arc surface are The arc surfaces are arranged coaxially, and the ray source is arranged on the axis of the first arc surface and the second arc surface.

As a preferred technical solution of the CT system, the second arc surface does not interfere with the rectangular channel, and the second arc surface does not exceed the outer diameter of the turret.

As a preferred technical solution of the CT system, the radius of the second arc surface is smaller than the radius of the first arc surface.

As a preferred technical solution of the CT system, the radius of the first arc surface is Ra, the radius of the second arc surface is Rb, the length of the intermediate detector is Da, and the length of the intermediate detector is Da. The length is Da, where Ra/Rb=Da/Db.

As a preferred technical solution of the CT system, the distance between the crystal modules on the middle detector is da, the distance between the crystal modules on the first sub-edge detector and the distance between the crystal modules on the second sub-edge detector. The intervals between modules are all db, and the first sub-edge detector is provided with N rows of crystal modules, and the middle detector is provided with 2N rows of crystal modules, where Db=db*(N-1), Da=da *(2N-1).

As a preferred technical solution of the CT system, the distance between the crystal module of the first sub-edge detector and the crystal module of the second sub-edge detector along the Z direction is 1/2db.

As a preferred technical solution of the CT system, the adjacent sides of the ray path irradiated by the ray source on the edge detector and the ray path irradiated by the ray source on the middle detector coincide with each other.

As a preferred technical solution of a CT system, there are multiple sets of edge detectors and multiple second arc surfaces, and multiple sets of edge detectors correspond to multiple second arc surfaces in one-to-one correspondence. .

On the other hand, a security inspection equipment is provided, including the CT system described in any of the above solutions.

The beneficial effects of the present invention are:

The invention provides a CT system and security inspection equipment. During operation, the turntable drives the radiation source and the detector assembly to rotate around the rectangular channel together. When the turntable rotates 360 degrees, a detection rectangular channel is formed between the radiation source and the edge detector. Annular edge detection area, in which the overlapping part of the annular edge detection area and the rectangular channel is the area that needs to be imaged, and the non-overlapping part of the annular edge detection area and the rectangular channel is air. There is no need to calculate and reconstruct the image, and the calculation amount is small. Therefore, the first sub-edge detector and the second sub-edge detector only need a small number of crystal modules to form an image of this layer thickness. The overlapping part of the annular edge detection area and the rectangular channel of the present invention is no larger than the non-overlapping part of the annular edge detection area and the rectangular channel, that is, the four sharp corner areas of the rectangular channel are detected. Compared with the middle detector, the edge detector needs to calculate the data The amount is reduced by more than half, so the number of rows of crystal modules on the first sub-edge detector and the number of rows of crystal modules on the second sub-edge detector can be set to half the number of rows of crystal modules on the middle detector, When the number of upper rows of the first sub-edge detector and the second sub-edge detector is reduced, the spacing between the crystal modules can be relatively increased, which reduces the processing difficulty of the first sub-edge detector and the second sub-edge detector, thereby reducing production cost.

Furthermore, since the first sub-edge detector and the second sub-edge detector are symmetrically arranged on both sides of the middle detector, the detection positions of the first sub-edge detector and the second sub-edge detector are in the same annular edge detection area. In order to To ensure the imaging effect of the annular edge detection area, the crystal module of the first sub-edge detector and the crystal module of the second sub-edge detector are staggered along the Z direction without overlapping positions, that is, the crystal module of the first sub-edge detector acquires The sum of the number of data layers and the number of data layers acquired by the crystal module of the second sub-edge detector is equal to the number of data layers acquired by the crystal module of the first sub-edge detector, which meets the imaging requirements of the CT system to form CT images.

Description of the drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, a brief introduction will be made below to the drawings needed to describe the embodiments of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention. , For those of ordinary skill in the art, other drawings can also be obtained based on the content of the embodiments of the present invention and these drawings without exerting creative efforts.

Figure 1 is one of the front views of a CT system provided by a specific embodiment of the present invention;

Figure 2 is a top view of an edge detector provided by a specific embodiment of the present invention;

Figure 3 is a top view of an intermediate detector provided by a specific embodiment of the present invention;

Figure 4 is a left view of the partial structure of the CT system provided by the specific embodiment of the present invention;

Figure 5 is the second front view of the CT system provided by the specific embodiment of the present invention;

Figure 6 is a schematic structural diagram of the security inspection equipment provided by the specific embodiment of the present invention.

The markings in the figure are as follows:

10. Object to be detected;

1. Rectangular channel;

2. Rotating component; 21. Turret; 22. Frame;

3. Ray source;

4. Detector assembly; 41. Middle detector; 42. Edge detector; 421. First sub-edge detector; 422. Second sub-edge detector; 423. Annular edge detection area; 4231. Overlapping part; 4232. Non-overlapping parts; 43. Crystal module; 44. Ray path;

5. Conveyor belt; 6. Data transmission components.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and examples. It can be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention. In addition, it should be noted that, for convenience of description, only some but not all structures related to the present invention are shown in the drawings.

In the description of the present invention, unless otherwise clearly stated and limited, the terms "connected", "connected" and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral body. ; It can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be an internal connection between two elements or an interaction between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.

In the present invention, unless otherwise expressly provided and limited, the term "above" or "below" a first feature of a second feature may include direct contact between the first and second features, or may also include the first and second features. Not in direct contact but through additional characteristic contact between them. Furthermore, the terms "above", "above" and "above" a first feature on a second feature include the first feature being directly above and diagonally above the second feature, or simply mean that the first feature is higher in level than the second feature. “Below”, “under” and “under” the first feature is the second feature includes the first feature being directly below and diagonally below the second feature, or simply means that the first feature is less horizontally than the second feature.

In the description of this embodiment, the terms "upper", "lower", "left", "right" and other orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplified operation. It is not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore is not to be construed as a limitation of the invention. In addition, the terms "first" and "second" are only used for descriptive purposes and have no special meaning.

As shown in FIGS. 1 to 3 , this embodiment provides a CT system, which includes a rectangular channel 1 extending along the Z direction, a rotating component 2 , a radiation source 3 and a detector component 4 .

Specifically, the rotating assembly 2 includes a turret 21, which is arranged around the rectangular channel 1; the ray source 3 and the detector assembly 4. Both the ray source 3 and the detector assembly 4 are installed with the turret 21, and the ray source 3 and the detection The detector assembly 4 is arranged on both sides of the rectangular channel 1; the detector assembly 4 includes a middle detector 41 and an edge detector 42. The edge detector 42 includes a first sub-edge detector 421 and a first sub-edge detector 421 that are symmetrically arranged on both sides of the middle detector 41. In the second sub-edge detector 422, the rays from the ray source 3 pass through the rectangular channel 1 and are irradiated on the detector assembly 4. When the turret 21 rotates 360 degrees, a detection rectangular channel 1 is formed between the ray source 3 and the edge detector 42. The annular edge detection area 423, the overlapping part 4231 of the annular edge detection area 423 and the rectangular channel 1 is not larger than the non-overlapping part 4232 of the annular edge detection area 423 and the rectangular channel 1; the middle detector 41, the first sub-edge detector 421 and The second sub-edge detectors 422 are each provided with multiple rows of crystal modules 43 evenly spaced along the Z direction. The number of rows of crystal modules 43 on the first sub-edge detector 421 and the number of rows of crystal modules 43 on the second sub-edge detector 422 are The number of rows is the same, and the number of rows of crystal modules 43 on the first sub-edge detector 421 is half of the number of rows of crystal modules 43 on the middle detector 41; the crystal modules 43 of the first sub-edge detector 421 and the second The crystal modules 43 of the sub-edge detectors 422 are staggered along the Z direction without overlapping positions.

During operation, the turret 21 drives the ray source 3 and the detector assembly 4 to rotate together around the rectangular channel 1. When the turret 21 rotates 360 degrees, an annular edge detection system for detecting the rectangular channel 1 is formed between the ray source 3 and the edge detector 42. Area 423, in which the overlapping portion 4231 of the annular edge detection area 423 and the rectangular channel 1 is the area that needs imaging, and the non-overlapping portion 4232 of the annular edge detection area 423 and the rectangular channel 1 is air. There is no need to calculate and reconstruct the image. Calculate The amount is small, so the first sub-edge detector 421 and the second sub-edge detector 422 only need a small amount of crystal modules 43 to form an image with this layer thickness. In this embodiment, the overlapping portion 4231 of the annular edge detection area 423 and the rectangular channel 1 is no larger than the non-overlapping portion 4232 of the annular edge detection area 423 and the rectangular channel 1, that is, the four sharp corner areas of the rectangular channel 1 are detected, relative to the middle detector 41. The amount of data that the edge detector 42 needs to calculate is reduced by more than half, so the row number of the crystal module 43 on the first sub-edge detector 421 and the row number of the crystal module 43 on the second sub-edge detector 422 can be set. becomes half the number of rows of crystal modules 43 on the middle detector 41. When the number of rows on the first sub-edge detector 421 and the second sub-edge detector 422 is reduced, the spacing of the crystal modules 43 can be relatively increased, reducing the The processing difficulty of the first sub-edge detector 421 and the second sub-edge detector 422 thereby reduces production costs.

Furthermore, as shown in Figures 1 to 3, since the first sub-edge detector 421 and the second sub-edge detector 422 are symmetrically arranged on both sides of the middle detector 41, the first sub-edge detector 421 and the second sub-edge detector 421 are symmetrically arranged on both sides of the middle detector 41. The detection position of the detector 422 is the same annular edge detection area 423. In order to ensure the imaging effect of the annular edge detection area 423, the crystal module 43 of the first sub-edge detector 421 and the crystal module 43 of the second sub-edge detector 422 are arranged along Arranged staggered in the Z direction without overlapping positions, the crystal module 43 of the first sub-edge detector 421 and the crystal module 43 of the second sub-edge detector 422 are equivalent to twice the actual size, as shown in Figures 2 and 3, that is, the first The sum of the number of data layers acquired by the crystal module 43 of the first sub-edge detector 421 and the number of data layers acquired by the crystal module 43 of the second sub-edge detector 422 is equal to the data layer acquired by the crystal module 43 of the first sub-edge detector 421 number to meet the imaging needs of the CT system to form CT images.

It should be noted that, as shown in FIG. 1 , the edge annular detection area formed between the ray source 3 and the edge detector 42 is an existing technology. Specifically, according to the two edges of the ray path 44 irradiated by the ray source 3 on the edge detector 42, a circumscribed circle is formed and two tangent points are formed. The center of the circumscribed circle is on the axis of the turret 21, and the two tangent points are connected. The line rotates around the axis of the turret 21 to form an edge annular detection area.

In this embodiment, as shown in FIG. 1 , the middle detector 41 is disposed on the first arc surface, and the edge detector 42 is disposed on the second arc surface. The first arc surface and the second arc surface are coaxial. is set, and the ray source 3 is set on the axis of the first arc surface and the second arc surface, so as to meet the imaging requirements of the CT system. Among them, on the first arc surface and the second arc surface, the turret 21 is provided with a mounting plate at corresponding positions, and the middle detector 41 and the edge detector 42 can be installed on the mounting plate.

Furthermore, the second arc surface does not interfere with the rectangular channel 1 , preventing the edge detector 42 from interfering with the rectangular channel 1 when rotating around the rectangular channel 1 , and the second arc surface does not exceed the outer diameter of the turret 21 .

In this embodiment, the radius of the second arc surface is smaller than the radius of the first arc surface. In this embodiment, the edge detector 42 is arranged on a smaller arc radius, so that the rotation radius of the turret 21 becomes smaller, thereby reducing the Small CT system size. In other embodiments, the radius of the second arc surface can also be larger than the radius of the first arc surface, thereby increasing the spacing between the crystal modules 43 on the edge detector 42 and reducing the production difficulty and cost of the edge detector 42 .

Further, as shown in Figures 2 to 4, the radius of the first arc surface is Ra, the radius of the second arc surface is Rb, the length of the middle detector 41 is Da, and the length of the middle detector 41 is Da, Among them, Ra/Rb=Da/Db, so as to meet the imaging requirements of the CT system. Among them, after selecting the positions of the first arc surface and the second arc surface, Ra, Rb and Da are all known numbers, and Db can be calculated according to Ra/Rb=Da/Db.

The distance between the crystal modules 43 on the middle detector 41 is da, the distance between the crystal modules 43 on the first sub-edge detector 421 and the distance between the crystal modules 43 on the second sub-edge detector 422 are both db, and the first The sub-edge detector 421 is provided with N rows of crystal modules 43, and the middle detector 41 is provided with 2N rows of crystal modules 43, where Db=db*(N-1) and Da=da*(2N-1). Among them, after Db is calculated, db can be calculated according to Db=db*(N-1), and da can be calculated according to Da=da*(2N-1). Among them, N is a natural number, and the selection of the N value is an existing technology and can be set according to the detection requirements.

Further preferably, the distance between the crystal module 43 of the first sub-edge detector 421 and the crystal module 43 of the second sub-edge detector 422 along the Z direction is 1/2db. The data layers formed by the crystal modules 43 of the two sub-edge detectors 422 have consistent intervals, which improves imaging quality and reduces calculation difficulty.

Preferably, as shown in FIG. 1 , the adjacent sides of the ray path 44 irradiated by the ray source 3 on the edge detector 42 and the ray path 44 irradiated by the ray source 3 on the middle detector 41 overlap to prevent the ray path 44 from collapsing. A gap is created between them to meet the imaging needs of the CT system.

Further preferably, as shown in FIG. 5 , there are multiple sets of edge detectors 42 and multiple second arc surfaces. The multiple sets of edge detectors 42 correspond to the multiple second arc surfaces one-to-one. The multiple edge detectors 42 can be installed on the second arc surface of different layers to further reduce the size of the CT system. The shape and area ratio of the theoretical imaging area and the actual position area of different groups of edge detectors 42 are also different, so different groups of edge detectors 42 can choose different configurations.

As shown in Figure 6, this embodiment also provides security inspection equipment, including the above-mentioned CT system. The rotating assembly 2 also includes a frame 22. The security inspection equipment also includes a conveyor belt 5 and a data transmission assembly 6. The turntable 21 is rotatably connected to the frame 22. The conveyor belt 5 is arranged in the rectangular channel 1, and the detected object 10 is installed on the conveyor belt. The data transmission component 6 performs calculation and imaging based on the detection information of the CT system. It should be noted that the CT system can also be used in CT equipment and other equipment used for CT imaging.

Note that the above are only the preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, it can also include more other equivalent embodiments, and the present invention The scope is determined by the scope of the appended claims.

Claims (10)

1. A CT system, characterized in that it includes: Rectangular channel (1) extending along the Z direction; A rotating assembly (2), which includes a rotating frame (21), and the rotating frame (21) is arranged around the rectangular channel (1); A ray source (3) and a detector assembly (4) are installed on the turret (21), and the ray source (3) and the detector assembly (4) are Detector components (4) are arranged on both sides of the rectangular channel (1); The detector assembly (4) includes a middle detector (41) and an edge detector (42). The edge detector (42) includes first sub-edges symmetrically arranged on both sides of the middle detector (41). The detector (421) and the second sub-edge detector (422), the rays of the ray source (3) pass through the rectangular channel (1) and irradiate the detector assembly (4), and the rotation When the frame (21) rotates 360 degrees, an annular edge detection area (423) for detecting the rectangular channel (1) is formed between the ray source (3) and the edge detector (42). The overlapping portion (4231) of the area (423) and the rectangular channel (1) is no larger than the non-overlapping portion (4232) of the annular edge detection area (423) and the rectangular channel (1); The middle detector (41), the first sub-edge detector (421) and the second sub-edge detector (422) are all provided with multiple rows of crystal modules (43) evenly spaced along the Z direction, The number of rows of crystal modules (43) on the first sub-edge detector (421) and the number of rows of crystal modules (43) on the second sub-edge detector (422) are the same, and the first The number of rows of crystal modules (43) on the sub-edge detector (421) is half of the number of rows of crystal modules (43) on the intermediate detector (41); The crystal module (43) of the first sub-edge detector (421) and the crystal module (43) of the second sub-edge detector (422) are staggered along the Z direction without overlapping positions. 2. The CT system according to claim 1, characterized in that the middle detector (41) is arranged on the first arc surface, and the edge detector (42) is arranged on the second arc surface, The first arc surface and the second arc surface are arranged coaxially, and the ray source (3) is arranged on the axis of the first arc surface and the second arc surface. 3. The CT system according to claim 2, characterized in that the second arc surface does not interfere with the rectangular channel (1), and the second arc surface does not exceed the turret (21) ) outer diameter. 4. The CT system according to claim 3, wherein the radius of the second arc surface is smaller than the radius of the first arc surface. 5. The CT system according to claim 2, characterized in that the radius of the first arc surface is Ra, the radius of the second arc surface is Rb, and the length of the intermediate detector (41) is Da, and the length of the intermediate detector (41) is Da, where Ra/Rb=Da/Db. 6. The CT system according to claim 5, characterized in that the spacing between the crystal modules (43) on the middle detector (41) is da, and the crystal modules on the first sub-edge detector (421) The spacing between the modules (43) and the spacing between the crystal modules (43) on the second sub-edge detector (422) are both db, and the first sub-edge detector (421) is provided with N rows of crystal modules ( 43), the intermediate detector (41) is provided with 2N rows of crystal modules (43), where Db=db*(N-1) and Da=da*(2N-1). 7. The CT system according to claim 6, characterized in that the crystal module (43) of the first sub-edge detector (421) and the crystal module (43) of the second sub-edge detector (422) are arranged along The interval in the Z direction is 1/2db. 8. The CT system according to claim 1, characterized in that the ray path (44) irradiated by the ray source (3) on the edge detector (42) is the same as the ray path (44) irradiated by the ray source (3) on the edge detector (42). The ray path (44) of the middle detector (41) coincides with the two adjacent sides. 9. The CT system according to claim 2, characterized in that the edge detectors (42) are in multiple groups, the second arc surfaces are in multiple groups, and the edge detectors (42) in multiple groups are The plurality of second arc surfaces correspond to each other one by one. 10. Security inspection equipment, characterized by comprising the CT system according to any one of claims 1-9.