CT imaging device and imaging method

Abstract

The present invention provides a CT imaging device and an imaging method, wherein the CT imaging device comprises an X-ray source, a detector, a rotating mechanism for connecting the X-ray source, and a first guide rail for connecting the detector, wherein the rotating mechanism and the first guide rail are located on the same plane, the X-ray source and the detector are relatively arranged on both sides of the rotation axis of the rotating mechanism, and the X-ray source can rotate along the circumference of the rotating mechanism; the detector can slide on the first guide rail, wherein the X-ray source uses a conical semi-fan beam as an outgoing beam, the X-ray source rotates a certain angle along the rotating mechanism, and the detector slides synchronously along the first guide rail, so that an imaging angle α is formed between the center line of the outgoing beam and the first guide rail, and 0°<α≤90°. Compared with the prior art, the present invention can realize non-stitched large field of view and wide object imaging to eliminate artifacts and reduce X-ray dose.

Description

Technical Field

[0001] The invention relates to a CT imaging device and an imaging method, and belongs to the field of medical imaging. Background Art

[0002] CBCT (Cone Beam Computer Tomography) is a new type of CT technology that has been used in clinical practice since the beginning of this century. It uses low-energy cone beam rays to rotate around the patient's imaging area to form an image, and has the characteristics of short imaging time and low radiation dose.

[0003] At present, the commonly used methods to increase the imaging field of view in CT systems include image stitching through multiple scans and offset imaging of the detector. However, the image stitching method is prone to produce stitching artifacts at the stitching point, affecting the imaging effect. Although the method of offset imaging of the detector can include the entire human cross section, since the cross section of the human body is wide and generally elliptical, the traditional circular large field of view imaging has blank imaging areas outside the human cross section, resulting in a waste of X-rays.

[0004] In view of this, it is indeed necessary to propose a CT imaging device and an imaging method to solve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a CT imaging device and an imaging method to achieve non-stitched large-viewing-field and wide-object imaging, so as to eliminate artifacts and reduce X-ray dose.

[0006] To achieve the above-mentioned purpose, the present invention provides a CT imaging device, comprising an X-ray source, a detector, a rotating mechanism for connecting the X-ray source, and a first guide rail for connecting the detector, wherein the rotating mechanism and the first guide rail are located on the same plane, the X-ray source and the detector are relatively arranged on both sides of the rotation axis of the rotating mechanism, and the X-ray source can rotate along the circumferential direction of the rotating mechanism; the detector can slide on the first guide rail, wherein the X-ray source uses a conical half-fan beam as an outgoing light beam, the X-ray source rotates a certain angle along the rotating mechanism, and the detector slides synchronously along the first guide rail, so that an imaging angle α is formed between the center line of the outgoing light beam and the first guide rail, and 0°<α≤90°.

[0007] As a further improvement of the present invention, the rotating mechanism is arranged in an arc shape, having a first end and a second end for connecting the first guide rail, the detector is slidably connected to the first guide rail and is located between the first end and the second end, and the sliding range of the detector on the first guide rail is smaller than the distance between the first end and the second end.

[0008] As a further improvement of the present invention, the first guide rail includes a fixing portion and a driving portion connected to the fixing portion, and the detector is connected to the driving portion and reciprocates along the extension direction of the first guide rail under the drive of the driving portion.

[0009] As a further improvement of the present invention, the X-ray source and the detector are linked during the imaging process, so that the detector can always receive the X-rays emitted by the X-ray source.

[0010] As a further improvement of the present invention, when the straight line where the centers of the X-ray source and the detector are located is defined to be coplanar with the rotation axis, the X-ray source and the detector are in an upright position, and the maximum moving distance of the detector from the upright position to both sides along the first guide rail is 20 cm.

[0011] As a further improvement of the present invention, the rotating mechanism is also provided with a second guide rail perpendicular to the first guide rail, the rotating mechanism and the first guide rail are in the same plane, the second guide rail is perpendicular to the rotation plane of the rotating mechanism, and the first guide rail and the second guide rail are both connected to the detector, and can respectively drive the detector to translate within the rotation plane or to translate relative to each other in a direction perpendicular to the rotation plane.

[0012] As a further improvement of the present invention, the rotating mechanism is further provided with a third guide rail and a fourth guide rail connected to the X-ray source, the rotating mechanism and the third guide rail are in the same plane, and the fourth guide rail is respectively arranged perpendicular to the third guide rail and the rotation plane, and can respectively drive the X-ray source to translate within the rotation plane or to translate relatively in a direction perpendicular to the rotation plane.

[0013] As a further improvement of the present invention, the first guide rail and the third guide rail are arranged opposite to and in parallel, the second guide rail and the fourth guide rail are arranged opposite to and in parallel, and the CT imaging device is also provided with a control component for controlling the rotation of the rotating mechanism, and the control component can control the detector to translate along the first guide rail and the second guide rail, and control the X-ray source to translate along the third guide rail and the fourth guide rail.

[0014] As a further improvement of the present invention, the distance from the X-ray source to the rotation axis is 60 cm, the distance from the detector to the rotation axis is 40 cm, and the area of ​​the detector is 43 cm*43 cm.

[0015] To achieve the above object, the present invention further provides a CT imaging method, which is applied to the CT imaging device as described above and mainly comprises the following steps:

[0016] Step S1, defining that when the straight line where the centers of the X-ray source and the detector are located is coplanar with the rotation axis, the X-ray source and the detector are in an upright position; then the control component controls the rotation mechanism to move to the region of interest of the object to be imaged, and drives the X-ray source and the detector to move to the upright position;

[0017] Step S2, the rotating mechanism drives the X-ray source and / or the detector to rotate along the extension direction of the rotating mechanism, so that the X-ray source and the detector rotate from the normal position to the offset position, so as to obtain a plurality of width projection data of the object to be imaged in its width direction;

[0018] Step S3, the rotating mechanism drives the X-ray source and / or the detector to translate along a direction parallel to the rotation axis, so that the X-ray source and the detector rotate from the upright position to the translated position, so as to obtain a plurality of length projection data of the object to be imaged in its length direction;

[0019] Step S4: the control component receives the plurality of width projection data and the plurality of length projection data to perform three-dimensional image reconstruction on the region of interest of the object to be imaged, so as to obtain a wide-field imaging image of the region of interest.

[0020] The beneficial effects of the present invention are as follows: the present invention can realize non-stitching large-viewing-field and wide-object imaging to eliminate artifacts and reduce X-ray dose. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a projection structure diagram of the CT imaging device of the first embodiment of the present invention when it is in the upright position.

[0022] Figure 2 yes Figure 1 Diagram of the projection structure when the detector is in the offset position.

[0023] Figure 3 yes Figure 1 A diagram showing the change in the relative position of the detector and the X-ray source.

[0024] Figure 4 It is a projection structure diagram of the CT imaging device of the second embodiment of the present invention when it is in the upright position.

[0025] Figure 5 yes Figure 4 Side view of.

[0026] Figure 6 yes Figure 3 Schematic diagram of the irradiation range of the imaging object when the X-ray source is located at 0°.

[0027] Figure 7yes Figure 3 Schematic diagram of the irradiation range of the imaging object when the X-ray source is located at 90°.

[0028] Figure 8 yes Figure 3 Schematic diagram of the irradiation range of the imaging object when the X-ray source is located at 180°.

[0029] Fig. 9 yes Figure 3 Schematic diagram of the irradiation range of the imaging object when the X-ray source is located at 270°.

[0030] Fig.10 is a comparison diagram of the field of view of the prior art and the imaging of the present invention, wherein Fig.10 a is the imaging field of view of the prior art, Fig.10 b is the imaging field of view of the present invention. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] It should be noted here that in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the scheme of the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0033] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0034] like Figure 1 and Figure 2 As shown, the present invention discloses a CT imaging device 100 for performing medical imaging on a human body. The CT imaging device 100 is provided with a base (not shown) and a rotating mechanism 3 arranged on the base, and the base is equipped with a moving component for moving the CT imaging device 100, and the moving component can be a pulley or other structure, which is not limited here.

[0035] An X-ray source 1 and a detector 2 are provided in the rotating mechanism 3. The X-ray source 1 and the detector 2 are relatively arranged on both sides of the rotating axis of the rotating mechanism 3. When rotating, the rotating mechanism 3 can drive the X-ray source 1 and the detector 2 to rotate synchronously, so that the X-ray source 1 is always facing the direction of the detector 2 during rotation, and the X-rays emitted by the X-ray source 1 can be correctly received by the detector 2.

[0036] Furthermore, the X-ray source 1 and the detector 2 are relatively stationary when they rotate synchronously. Under the condition of relative stillness, the detector 2 can rotate along the rotating mechanism 3 and around the rotating axis, so that the detector 2 is offset relative to the X-ray source 1, so that the imaging center can deviate from the rotating axis, thereby increasing the imaging field of view. Specifically, the detector 2 can move along the rotating mechanism 3, or the X-ray source 1 can move along the rotating mechanism 3, as long as the detector 2 and the X-ray source 1 move relative to each other, and there is no limitation here.

[0037] On this basis, the X-ray source 1 and the detector 2 are linked during the imaging process, so that the detector 2 can always receive the X-rays emitted by the X-ray source 1, that is, the X-ray source 1 can adjust the direction of the X-ray emission according to the position of the detector 2, and adjust the angle of the emitted cone beam X-rays. Since the projection area received by the detector 2 is the largest when the detector 2 is facing the X-ray source 1, the angle of the cone beam X-rays emitted by the X-ray source 1 is the largest at this time. When the detector 2 moves, the projection area of ​​the detector 2 relative to the X-ray source 1 changes. At this time, the X-ray source 1 should move with the detector 2 and reduce the angle of the emitted cone beam X-rays so that the detector 2 can completely receive the cone beam X-rays.

[0038] In a preferred embodiment of the present invention, the rotating mechanism 3 includes a first guide rail 21 fixed in the same plane as the rotating mechanism 3, and the detector 2 is disposed on the first guide rail 21 and can move back and forth along the first guide rail 21. Since the first guide rail 21 is fixed on the rotating mechanism 3, the first guide rail 21 is stationary relative to the rotating mechanism 3. At this time, during the rotation of the X-ray source 1 and the detector 2 driven by the rotating mechanism 3, the X-ray source 1 is in a stationary state relative to the first guide rail 21, and when the detector 2 moves along the first guide rail 21, the detector 2 can move relative to the X-ray source 1.

[0039] like Figure 1 and Figure 2As shown, the rotating mechanism 3 and the first guide rail 21 are located on the same plane, the X-ray source 1 and the detector 2 are relatively arranged on both sides of the rotation axis of the rotating mechanism 3, and the X-ray source 1 can rotate along the circumferential direction of the rotating mechanism 3; the detector 2 can slide on the first guide rail 21, wherein the X-ray source 1 uses a conical half-fan beam as an outgoing light beam, the X-ray source 1 rotates a certain angle along the rotating mechanism 3, and the detector 2 slides synchronously along the first guide rail 21, so that an imaging angle α is formed between the center line of the outgoing light beam and the first guide rail 21, and 0°<α≤90°.

[0040] Further, the rotating mechanism 3 is arranged in an arc shape, and has a first end and a second end for connecting the first guide rail 21, the detector 2 is slidably connected to the first guide rail 21 and is located between the first end and the second end, and the sliding range of the detector 2 on the first guide rail 21 is smaller than the distance between the first end and the second end. Further, the first guide rail 21 includes a fixing portion (not shown) and a driving portion (not shown) connected to the fixing portion, and the detector 2 is connected to the driving portion and reciprocates along the extension direction of the first guide rail 21 under the drive of the driving portion.

[0041] Specifically, the X-ray source 1 is arranged opposite to the first guide rail 21, and the distance from the X-ray source 1 to the rotation axis is set to 60 cm, the distance from the first guide rail 21 to the rotation axis is set to 40 cm, and the area of ​​the detector 2 is 43 cm*43 cm. That is, the distance from the X-ray source 1 to the first guide rail 21 is 100 cm, and the distance from the detector 2 to the rotation axis is also set to 40 cm.

[0042] like Figure 3The figure shows the relationship between the position change of the detector 2 relative to the first guide rail 21 and the X-ray source 1. When the straight line where the centers of the X-ray source 1 and the detector 2 are located is defined to be coplanar with the rotation axis, the X-ray source 1 and the detector 2 are in the normal position. The range in which the detector 2 can be displaced relative to the first guide rail 21 is [-20, 20] (cm), which is the range of the offset position. Among them, when the distance displaced by the detector 2 relative to the first guide rail 21 is 0 cm, the detector 2 is in the normal position. During the imaging process, when the detector 2 rotates synchronously with the X-ray source 1 and is in the normal position, the range in which the detector 2 is displaced relative to the first guide rail 21 is [0, 20] (cm). It is worth noting that the detector 2 only moves within the range on one side or the other side of the first guide rail 21 relative to the normal position. That is, in a single imaging process, the range of movement of the detector 2 relative to the upright position is [-20, 0] (cm) or (0, 20] (cm). In an embodiment of the present invention, the range of the maximum imaging field of view obtained based on the above movement range is 39cm*26cm. Furthermore, since the range of displacement of the detector 2 relative to the first guide rail 21 is [-20, 20] (cm), and the length and width of the detector 2 are both 43cm, the length of the first guide rail 21 is at least 83cm. When the length of the first guide rail 21 is greater than 83cm, the range of movement of the detector 2 is also increased accordingly. Such a setting can further expand the field of view in the width direction of the imaged object. The specific length of the first guide rail 21 can be set as needed and is not limited here.

[0043] like Figure 4 and Figure 5 As shown, in the second embodiment of the present invention, a CT imaging device 200 is also included, and the CT imaging device 200 includes an X-ray source 1, a detector 2, a rotating mechanism 3, and a first guide rail 21 and a second guide rail 22 arranged on the rotating mechanism. The X-ray source 1 and the detector 2 are relatively arranged on both sides of the rotation axis of the rotating mechanism 3, and the rotating mechanism 3 is used to drive the X-ray source 1 and the detector 2 to rotate synchronously in the rotation plane. The first guide rail 21 and the second guide rail 22 are both connected to the detector 2 to respectively drive the detector 2 to translate in the rotation plane, or to translate relatively in a direction perpendicular to the rotation plane. In this embodiment, the rotating mechanism 3 and the first guide rail 21 are in the same plane, and the second guide rail 22 is respectively arranged perpendicular to the first guide rail 21 and the rotation plane.

[0044] Furthermore, the rotating mechanism 3 is also provided with a third guide rail 11 and a fourth guide rail 12 connected to the X-ray source 1, so as to respectively drive the X-ray source 1 to translate in the rotation plane, or to translate relatively in a direction perpendicular to the rotation plane. The rotating mechanism 3 and the third guide rail 11 are in the same plane, and the fourth guide rail 12 is respectively arranged perpendicular to the third guide rail 11 and the rotation plane.

[0045] Specifically, the specific parameters of the second guide rail 22, the third guide rail 11 and the fourth guide rail 12 are the same as those of the first guide rail 21, and are not repeated here. In this embodiment, the first guide rail 21 and the third guide rail 11 are arranged opposite and in parallel, the second guide rail 22 and the fourth guide rail 12 are arranged opposite and in parallel, and the centers of the first guide rail 21 and the third guide rail 11 are in the upright position, and the X-ray source 1 and the detector 2 are initially arranged in the upright position. In this embodiment, the first guide rail 21 and the second guide rail 22 are roughly in the shape of a cross, and the third guide rail 11 and the fourth guide rail 12 are also roughly in the shape of a cross. Of course, the first guide rail 21 and the second guide rail 22, as well as the third guide rail 11 and the fourth guide rail 12 can also be other structural forms, including but not limited to L-shaped structures, as long as they can realize the translation of the detector 2 and the X-ray source 1 in two directions perpendicular to each other.

[0046] Based on the above embodiment, the detector 2 and the X-ray source 1 can be respectively separated from each other in the horizontal direction on the second guide rail 22 and the fourth guide rail 12. Since the first guide rail 21 and the third guide rail 11 are arranged in parallel, the second guide rail 22 and the fourth guide rail 12 are also parallel, that is, the X-ray source 1 can be displaced relative to the rotating mechanism 3 in a direction perpendicular to the rotation plane, and the detector 2 can be displaced relative to the rotating mechanism 3 in a direction perpendicular to the rotation plane, thereby expanding the imaging range in the axial direction.

[0047] Preferably, the rotating mechanism 3 is annular so as to drive the X-ray source 1 and the detector 2 to rotate when the rotating mechanism 3 rotates. In other embodiments of the present invention, the first guide rail 21 and the third guide rail 11 are arranged on the radial inner side of the rotating mechanism 3, and the first guide rail 21 and the third guide rail 11 can rotate around the rotating mechanism 3 respectively. Further, the CT imaging device 100 is also provided with a control component for controlling the rotation of the rotating mechanism 3, and the control component can control the detector 2 to translate along the first guide rail 21 and the second guide rail 22, and control the X-ray source 1 to translate along the third guide rail 11 and the fourth guide rail 12.

[0048] like Figures 6 to 9 As shown, the present invention also provides a CT imaging method, which mainly includes the following steps:

[0049] Step S1, when it is defined that the straight line where the centers of the X-ray source 1 and the detector 2 are located is coplanar with the rotation axis, the X-ray source 1 and the detector 2 are in an upright position; the control component controls the rotating mechanism 3 to move to the region of interest of the object to be imaged, and drives the X-ray source 1 and the detector 2 to move to the upright position;

[0050] Step S2, the rotating mechanism 3 drives the X-ray source 1 and / or the detector 2 to rotate along the extension direction of the rotating mechanism 3, so that the X-ray source 1 and the detector 2 rotate from the normal position to the offset position, so as to obtain a plurality of width projection data of the object to be imaged in its width direction;

[0051] Step S3, the rotating mechanism 3 drives the X-ray source 1 and / or the detector 2 to translate along a direction parallel to the rotation axis, so that the X-ray source 1 and the detector 2 rotate from the upright position to the translated position, so as to obtain a plurality of length projection data of the object to be imaged in its length direction;

[0052] Step S4: the control component receives the plurality of width projection data and the plurality of length projection data to perform three-dimensional image reconstruction on the region of interest of the object to be imaged, so as to obtain a wide-field imaging image of the region of interest.

[0053] Steps S1-S4 will be described in detail below.

[0054] In step S1, at the initial moment, when the X-ray source 1 and the detector 2 are in the same rotation plane, the control component controls the rotating mechanism 3 to drive the X-ray source 1 and the detector 2 to rotate synchronously. At this time, the X-ray source 1 and the detector 2 are arranged opposite to each other, and the rotating mechanism 3 and the first guide rail 21 respectively drive the X-ray source 1 and the detector 2 to rotate synchronously around the imaging object for imaging.

[0055] In step S2, the horizontal direction perpendicular to the rotation axis is defined as the width direction, and the direction of the rotation axis is defined as the length direction. That is, taking a side-lying human body as an example, the extension direction of the human body width is the width direction, and the extension direction of the human body height is the length direction.

[0056] When the X-ray source 1 is in the normal position, the detector 2 moves from the normal position to the offset position around the imaged object relative to the X-ray source 1 to detect the width portion of the imaged object to increase the field of view in the width direction of the imaged object.

[0057] When the rotating mechanism 3 drives the X-ray source 1 to rotate to the upright position and face the imaged object, the cone beam X-rays emitted by the X-ray source 1 are limited in angle and cannot cover the entire width of the imaged object. Therefore, the entire imaged object can be divided into two equal parts in the width direction, and the two parts are respectively projected for 180° continuously to obtain an image with an expanded field of view. Specifically, when the X-ray source 1 is in the upright position and faces the imaged object, the detector 2 moves to the offset position, and the direction of the cone beam X-rays emitted by the X-ray source 1 changes with the detector 2 to cover one of the two parts of the imaged object and project for 180° continuously; when the X-ray source 1 rotates to the other side of the upright position, it covers the other of the two parts of the imaged object and also projects for 180° continuously. Thus, while expanding the field of view of the imaged object in the width direction, a complete image of the imaged object in a non-stitched form can be obtained.

[0058] like Fig.10 As shown, when the X-ray source 1 is located in the width direction of the imaging object, the detector 2 is reset from the biased position to the normal position so that the field of view in the width direction of the imaging object adapts to the range of the imaging object. Since the imaging object is approximately elliptical, there is no need to bias the width portion to expand the imaging field of view. If the biased state of the detector 2 is maintained for projection, the obtained imaging image will have a large number of blank spaces in the height direction of the human body, resulting in waste. Specifically, when the X-ray source 1 is located in the width direction of the imaging object and is facing the imaging object, the cross section of the human body falls within the range of the cone beam X-ray. The detector 2 does not need to be biased for projection, and should be moved to the normal position so that the field of view in the normal position adapts to the range of the imaging object, so as to obtain multiple width projection data of the object to be imaged in its width direction.

[0059] In step S3, when the X-ray source 1 and the detector 2 are not in the same rotation plane, the X-ray source 1 and the detector 2 move away from each other in a direction perpendicular to the rotation plane to image the object in an inclined direction, thereby obtaining multiple length projection data of the object to be imaged in its length direction.

[0060] Since the X-ray source 1 and the detector 2 move away from each other in a direction perpendicular to the rotation plane, that is, the X-ray source 1 and the detector 2 move along the second guide rail and the fourth guide rail respectively, they can be translated in the same or opposite directions. When the X-ray source 1 and the detector 2 translate from the initial position to opposite directions on both sides, the vertical distance between the X-ray source 1 and the detector 2 remains unchanged, and the horizontal distance increases. The X-rays emitted by the X-ray source 1 are received by the detector 2 at a certain inclination angle, so that the imaged object is imaged in an inclined direction. In practical applications, the imaging object can be imaged from different angles without moving it. With this arrangement, when the rotating mechanism 3 is set horizontally or vertically, there is no need to rotate the rotating mechanism 3 to make it scan at an angle, so as to simplify the device structure.

[0061] In step S4, after multiple scanning and imaging, the control component reconstructs a three-dimensional image of the multiple width projection data and the multiple length projection data of the collected imaging object. In addition, it should be noted that the control component may include software, hardware, or a combination thereof. For example, the control component may be a virtual component, and its function may be implemented by executing corresponding software on a computer. In some embodiments, the control component may be a separate component or other components, such as a part of a computer.

[0062] In particular, the above description of the movement of the detector 2 relative to the X-ray source 1 does not limit the detector 2, but only represents the relative movement between the detector 2 and the X-ray source 1. That is to say, in other embodiments of the present invention, the X-ray source 1 may also be moved, which is not limited here.

[0063] In summary, the present invention can achieve non-stitching large field of view and wide object imaging to eliminate artifacts and reduce X-ray dose.

[0064] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A CT imaging device, characterized in that: The invention comprises an X-ray source, a detector, a rotating mechanism for connecting the X-ray source, and a first guide rail for connecting the detector, wherein the rotating mechanism and the first guide rail are located on the same plane, the X-ray source and the detector are relatively arranged on both sides of the rotation axis of the rotating mechanism, and the X-ray source can rotate along the circumference of the rotating mechanism; the detector can slide on the first guide rail, wherein the X-ray source uses a conical semi-fan beam as an outgoing light beam, the X-ray source rotates a certain angle along the rotating mechanism, and the detector slides synchronously along the first guide rail, so that an imaging angle α is formed between the center line of the outgoing light beam and the first guide rail, and 0°<α≤90°; the rotating mechanism is arranged in a superior arc shape, and has a first end and a second end for connecting to the first guide rail, the detector is slidably connected to the first guide rail, and is located at the first guide rail. The rotating mechanism is provided with a second guide rail which is perpendicular to the first guide rail, the rotating mechanism and the first guide rail are in the same plane, the second guide rail is perpendicular to the rotation plane of the rotating mechanism, the first guide rail and the second guide rail are both connected to the detector, and can respectively drive the detector to translate in the rotation plane or to translate relatively in a direction perpendicular to the rotation plane; the rotating mechanism is also provided with a third guide rail and a fourth guide rail which are connected to the X-ray source, the rotating mechanism and the third guide rail are in the same plane, the fourth guide rail is respectively perpendicular to the third guide rail and the rotation plane, and can respectively drive the X-ray source to translate in the rotation plane or to translate relatively in a direction perpendicular to the rotation plane.

2. The CT imaging device according to claim 1, characterized in that: The first guide rail includes a fixing portion and a driving portion connected to the fixing portion. The detector is connected to the driving portion and reciprocates along the extending direction of the first guide rail under the driving of the driving portion.

3. The CT imaging device according to claim 1, characterized in that: The X-ray source and the detector are linked together during the imaging process, so that the detector can always receive the X-rays emitted by the X-ray source.

4. The CT imaging device according to claim 1, characterized in that: When the straight line defining the centers of the X-ray source and the detector is coplanar with the rotation axis, the X-ray source and the detector are in an upright position, and the maximum moving distance of the detector from the upright position to both sides along the first guide rail is 20 cm.

5. The CT imaging device according to claim 1, characterized in that: The first guide rail and the third guide rail are arranged opposite to each other and in parallel, the second guide rail and the fourth guide rail are arranged opposite to each other and in parallel, and the CT imaging device is also provided with a control component for controlling the rotation of the rotating mechanism, and the control component can control the detector to translate along the first guide rail and the second guide rail, and control the X-ray source to translate along the third guide rail and the fourth guide rail.

6. The CT imaging device according to claim 1, characterized in that: The distance from the X-ray source to the rotation axis is 60 cm, the distance from the detector to the rotation axis is 40 cm, and the area of ​​the detector is 43 cm*43 cm.

7. A CT imaging method, applied to the CT imaging device according to any one of claims 1 to 6, characterized in that: The main steps include: Step S1, when it is defined that the straight line where the centers of the X-ray source and the detector are located is coplanar with the rotation axis, the X-ray source and the detector are in an upright position; the control component controls the rotation mechanism to move to the region of interest of the object to be imaged, and drives the X-ray source and the detector to move to the upright position; Step S2, the rotating mechanism drives the X-ray source and / or the detector to rotate along the extension direction of the rotating mechanism, so that the X-ray source and the detector rotate from the normal position to the offset position, so as to obtain a plurality of width projection data of the object to be imaged in its width direction; Step S3, the rotating mechanism drives the X-ray source and / or the detector to translate along a direction parallel to the rotation axis, so that the X-ray source and the detector rotate from the upright position to the translated position, so as to obtain a plurality of length projection data of the object to be imaged in its length direction; Step S4: the control component receives the plurality of width projection data and the plurality of length projection data to perform three-dimensional image reconstruction on the region of interest of the object to be imaged, so as to obtain a wide-field imaging image of the region of interest.

Images