Mobile digital X-ray machine and position calibration method

Abstract

The invention discloses a mobile digital X-ray machine and a position calibration method. The mobile digital X-ray machine comprises a radiation source, a magnetic field generator, a flat panel detector and a magnetic field sensor group, firstly, X-rays emitted by a ray source coincide with central magnetic lines of force of a magnetic field generator; secondly, the magnetic field sensor group is symmetrically arranged based on the geometric center of the surface of the flat panel detector; and finally, adjusting the position of the radiation source and / or the flat panel detector, so that the magnetic induction intensity detected by the magnetic field sensor group is symmetrical based on the X-ray, the X-ray is aligned with the geometric center of the surface of the flat panel detector, and the purpose of accurately aligning the radiation source and the flat panel detector is achieved. In addition, the device has the advantages of being simple in structure and convenient to operate.

Description

Technical Field

[0001] The present invention relates to the field of medical imaging, and in particular to a mobile digital X-ray machine and a position calibration method. Background Art

[0002] DR machine (digital X-ray machine) is a medical device based on digital imaging technology. The digital X-ray machine converts X-rays into digital signals through the internal flat-panel detector, and generates high-resolution images after computer processing. Therefore, digital X-ray machines are widely used in the field of clinical diagnosis. However, in clinical work, many patients are unable to go to the radiology department for routine radiological examinations due to their illness. Therefore, in order to facilitate the examination of critically ill patients, mobile digital X-ray machines came into being. For patients who are not convenient to go to the DR room for examination, medical staff can push the mobile digital X-ray machine to the bedside for photographic examination. For patients who are unable to move and need X-ray examinations, the risk of moving between wards and examination rooms is reduced.

[0003] However, for digital X-ray machines, it is necessary to ensure that the relative position between the internal radiation source and the internal flat-panel detector is calibrated to ensure the best imaging quality. When the relative position of the flat-panel detector and the radiation source changes, the calibration may fail and the image quality will be greatly reduced. Therefore, in the clinical application of mobile digital X-ray machines, due to the complex and changeable use environment, how to ensure the alignment of the radiation source and the flat-panel detector has become a difficult problem to solve.

[0004] Existing technologies attempt to solve the problem of calibration failure using optical and radio frequency means, but since there is usually a patient blocking the radiation source and the flat-panel detector, optical and radio frequency positioning means are difficult to solve the current calibration failure problem. At present, the alignment between the radiation source and the flat-panel detector inside the mobile digital X-ray machine still relies entirely on the experience of doctors or technicians. There is no auxiliary alignment method available. If the image cannot be used due to positioning problems, a second positioning exposure is usually selected, resulting in an increase in the patient's dose.

[0005] Therefore, how to accurately and quickly calibrate the relative position between the radiation source and the flat panel detector has become one of the problems that technicians in this field need to solve urgently.

[0006] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present invention and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because these solutions are described in the background technology section of the present invention. Summary of the invention

[0007] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a mobile digital X-ray machine and a position calibration method to solve the problem in the prior art that the relative position between the radiation source and the flat panel detector cannot be accurately and quickly calibrated.

[0008] To achieve the above-mentioned purpose and other related purposes, the present invention provides a mobile digital X-ray machine, which at least includes: a ray source, a magnetic field generator, a flat-panel detector and a magnetic field sensor group; the ray source is used to generate X-rays; the magnetic field generator is used to generate a magnetic field, and the central magnetic field lines of the magnetic field generator coincide with the X-rays; wherein the magnetic induction intensity in the cross-section of the X-rays is symmetrical based on the X-rays; the flat-panel detector is used to receive the X-rays, and the plane where the flat-panel detector is located is perpendicular to the X-rays; the magnetic field sensor group includes n magnetic field sensors, the n magnetic field sensors are all arranged on the surface of the flat-panel detector, the surface is perpendicular to the X-rays, and the magnetic field sensor group is symmetrically arranged based on the geometric center of the surface; wherein n is a natural number greater than or equal to 2.

[0009] Optionally, the magnetic field generator is any one of a circular coil or a solenoid.

[0010] More optionally, the magnetic field sensor group is arranged in an X-shape, a crisscross shape or a circle on the flat-panel detector.

[0011] Optionally, the magnetic field generator is any one of a rectangular coil, a regular hexagonal coil or a regular octagonal coil.

[0012] More optionally, the magnetic field sensor group is arranged on the flat-panel detector in a cross shape, a criss-cross shape, a rectangle, a regular hexagon or a regular octagon.

[0013] To achieve the above-mentioned purpose and other related purposes, the present invention also provides a position calibration method, the steps of which include at least: S1: making the plane where the flat-panel detector is located receive X-rays vertically; generating a magnetic field whose central magnetic lines of force coincide with the X-rays, and the magnetic induction intensity of the magnetic field is symmetrical based on the X-rays within the cross-section of the X-rays; setting a magnetic field sensor group on the surface of the flat-panel detector, and the surface is perpendicular to the X-rays; the magnetic field sensor group is symmetrically arranged based on the geometric center of the surface; S2: adjusting the position of the ray source and / or the flat-panel detector so that the geometric center of the surface is on the X-rays.

[0014] Optionally, in step S2, the ray source is translated in the cross-section of the X-ray and / or the flat-panel detector is translated in the cross-section of the X-ray to adjust the position of the ray source and / or the flat-panel detector.

[0015] Optionally, in step S2, when the magnetic induction intensity of the magnetic field sensor group is symmetrical based on the X-ray, it is determined that the geometric center of the surface is on the X-ray.

[0016] As described above, the mobile digital X-ray machine and position calibration method of the present invention have the following beneficial effects:

[0017] 1. The present invention firstly makes the X-rays emitted by the ray source coincide with the central magnetic lines of force of the magnetic field generator, and then sets the magnetic field sensor group around the geometric center of the flat-panel detector surface. When it is observed that the magnetic induction intensity is symmetrically distributed based on the X-rays, it can be considered that the X-rays have been aligned with the geometric center of the flat-panel detector surface. Therefore, the present invention can achieve the purpose of quickly and accurately aligning the ray source and the flat-panel detector.

[0018] 2. The present invention arranges the magnetic field sensor group on the surface of the flat-panel detector in a circle, rectangle, regular hexagon, regular octagon, X, cross or Piece shape, which can adapt to the magnetic field generated by a circular coil, a solenoid, a rectangular coil, a regular hexagonal coil or a regular octagonal coil. Therefore, the present invention can speed up the alignment of the radiation source and the flat-panel detector and improve the accuracy of the alignment of the radiation source and the flat-panel detector. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Shown is a structural schematic diagram of the mobile digital X-ray machine of the present invention.

[0020] Figure 2 It is a schematic diagram showing the first symmetry axis of the magnetic field generator of the present invention in the X-ray cross section.

[0021] Figure 3 It is a schematic diagram showing a second symmetry axis of the magnetic field generator of the present invention in the X-ray cross section.

[0022] Figure 4 It is a schematic diagram showing the third symmetry axis of the magnetic field generator of the present invention in the X-ray cross section.

[0023] Figure 5 It is a schematic diagram showing a first arrangement of the magnetic field sensor group of the present invention.

[0024] Figure 6 It is a schematic diagram showing a second arrangement of the magnetic field sensor group of the present invention.

[0025] Figure 7 It is a schematic diagram showing a third arrangement of the magnetic field sensor group of the present invention.

[0026] Figure 8 It is a schematic diagram showing a fourth arrangement of the magnetic field sensor group of the present invention.

[0027] Fig. 9 Shown is a flow chart of the position calibration method of the present invention.

[0028] Fig.10 It shows a first schematic diagram of the magnetic induction intensity of the magnetic field sensor group on the X-axis of the present invention.

[0029] Fig.11 A second schematic diagram showing the magnetic induction intensity of the magnetic field sensor group on the X-axis of the present invention is shown.

[0030] Component number description

[0031] 1 Radiation source

[0032] 2 Magnetic field generator

[0033] 3 Flat panel detector

[0034] 4 Magnetic Field Sensor Group

[0035] 4a First magnetic field sensor

[0036] 4b Second magnetic field sensor

[0037] 4c Third magnetic field sensor

[0038] 4d Fourth magnetic field sensor

[0039] 4e Fifth Magnetic Field Sensor

[0040] 4f Sixth magnetic field sensor

[0041] 4g seventh magnetic field sensor

[0042] 4h Eighth magnetic field sensor DETAILED DESCRIPTION

[0043] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0044] See also Figure 1-Figure 11 It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0045] Since there is an obstruction between the radiation source and the flat panel detector, it is difficult for optical and radio frequency positioning methods to solve the alignment problem between the radiation source and the flat panel detector, that is, it is difficult to align the X-rays emitted by the radiation source with the geometric center of the flat panel detector surface (the surface of the flat panel detector receiving the X-rays and the surface parallel to the surface receiving the X-rays). Therefore, the present invention takes into account the avoidance of the patient's obstruction, the reduction of the risk to human health, and the need for precise alignment of the digital X-ray machine, and selects the magnetic field as the physical parameter required for the positioning of the present invention from among many physical parameters. The specific implementation of the present invention is as follows:

[0046] Embodiment 1

[0047] like Figure 1 As shown, this embodiment provides a mobile digital X-ray machine, which includes: a ray source 1, a magnetic field generator 2, a flat panel detector 3 and a magnetic field sensor group 4.

[0048] like Figure 1 As shown, the radiation source 1 is used to generate X-rays.

[0049] Specifically, in this embodiment, the ray source 1 of the mobile digital X-ray machine emits X-rays, which can pass through the target object to obtain a two-dimensional image or a three-dimensional image of the target object. In this process, the target object will receive a certain amount of X-ray radiation. Therefore, quickly aligning the ray source 1 and the flat panel detector 3 can prevent the target object from excessively receiving X-ray radiation. In practical applications, any device that can generate X-rays can be used as the ray source 1 of the present invention, not limited to this embodiment.

[0050] like Figure 1 As shown, the magnetic field generator 2 is used to generate a magnetic field, and the central magnetic field lines of the magnetic field generator 2 coincide with the X-rays; wherein the magnetic induction intensity within the cross-section of the X-rays is symmetric based on the X-rays.

[0051] Specifically, in this embodiment, the magnetic field generator 2 can be any one of a rectangular coil (or a square coil), a regular hexagonal coil or a regular octagonal coil, and the magnetic field generator 2 can also be any one of a circular coil or a solenoid, wherein the central magnetic field line of the magnetic field generator extends along the axis of the magnetic field generator 2. When the central magnetic field line of the magnetic field generator 2 coincides with the X-ray, the magnetic field generated by the magnetic field generator 2 in the X-ray cross section will be symmetrical around the X-ray, and then the X-ray emitted by the ray source 1 can be located according to the characteristics of the central magnetic field line in the magnetic field. In practical applications, the magnetic field generator 2 can be any device that can generate a magnetic field in a cross section that is symmetrical around the central magnetic field line, and is not limited to this embodiment.

[0052] Specifically, in this embodiment, when the magnetic field generator 2 is a circular coil or a solenoid, in the cross section of the X-ray, Figure 2 As shown, the magnetic induction intensity on any symmetry axis of the magnetic field generator 2 is symmetric based on the central magnetic field line. Further, when the magnetic field generator 2 is a rectangular coil, a regular hexagonal coil or a regular octagonal coil, as Figure 3 and Figure 4 As shown, in the cross section of the X-ray, the magnetic induction intensity on any symmetry axis of the magnetic field generator 2 is also symmetric based on the central magnetic field line.

[0053] like Figure 1 As shown, the flat panel detector 3 is used to receive X-rays, and the plane where the flat panel detector 3 is located is perpendicular to the X-rays.

[0054] Specifically, in this embodiment, the target object is located between the ray source 1 and the flat panel detector 3, and the image of the target object can be obtained after the flat panel detector 3 receives the X-rays. Furthermore, the plane where the flat panel detector 3 is located is parallel to the surface of the flat panel detector 3 receiving the X-rays, so the X-rays are emitted vertically to the flat panel detector 3.

[0055] like Figure 1 As shown, the magnetic field sensor group 4 includes n magnetic field sensors, which are all arranged on the surface of the flat-panel detector 3, the surface of the flat-panel detector is perpendicular to the X-rays, and the magnetic field sensor group is arranged symmetrically based on the geometric center of the surface; wherein n is a natural number greater than or equal to 2.

[0056] Specifically, in this embodiment, the surface of the flat panel detector 3 refers to the surface of the flat panel detector 3 that receives X-rays and the surface of the flat panel detector 3 that is parallel to the surface. In order to align the X-rays with the geometric center of the surface of the flat panel detector 3, the magnetic field sensor group is symmetrically arranged based on the geometric center of the surface of the flat panel detector 3. Further, in order to achieve the purpose of quickly and accurately aligning the detector with the radiation source, the arrangement of the magnetic field sensor group 4 is set by observing the shape of the coil. When the magnetic field generator 2 is a circular coil or a solenoid, as shown in FIG. Figure 5 , Figure 6 and Figure 7 As shown, the magnetic field sensor group 4 can be arranged in an X-shape (the angle between the two sides of the X-shape can be arbitrary), a cross-shaped arrangement or a circular arrangement (the circular arrangement corresponds to a circular coil shape and a solenoid shape in an X-ray cross section). Furthermore, when the magnetic field generator 2 is a rectangular coil, as shown in FIG. Figure 5 As shown, the magnetic field sensor group 4 can be arranged in a cross shape; or as Figure 6 As shown, the magnetic field sensor group 4 can be arranged in a cross shape; or as Figure 8As shown, the magnetic field sensor group 4 can be arranged in a rectangular shape (rectangular arrangement corresponds to a rectangular coil shape). Furthermore, when the magnetic field generator 2 is a regular hexagonal coil, the magnetic field sensor group 4 can be arranged in a cross shape, a cross-shaped arrangement, or a regular hexagonal arrangement (regular hexagonal arrangement corresponds to a regular hexagonal coil shape). Furthermore, when the magnetic field generator 2 is a regular octagonal coil, the magnetic field sensor group 4 can be arranged in a cross shape, a cross-shaped arrangement, or a regular octagonal arrangement (regular octagonal arrangement corresponds to a regular octagonal coil shape). As an example, Figure 1 As shown, the magnetic field generator 2 is a rectangular coil, and the magnetic field sensor group 4 on the surface of the flat panel detector 3 is arranged in a cross shape; Figure 5 As shown, on one side of the cross: the first magnetic field sensor 4a, the second magnetic field sensor 4b, the third magnetic field sensor 4c, the fourth magnetic field sensor 4d, the fifth magnetic field sensor 4e, the sixth magnetic field sensor 4f, the seventh magnetic field sensor 4g and the eighth magnetic field sensor 4h are arranged in sequence, and are arranged symmetrically based on the geometric center of the surface of the flat panel detector. Further, when the magnetic induction intensity detected by the magnetic field sensor group 4 is symmetrical based on the X-ray, it can be considered that the geometric center of the surface of the flat panel detector 3 is already on the X-ray, so the present invention achieves the purpose of aligning the X-ray with the geometric center of the surface of the flat panel detector 3.

[0057] Embodiment 2

[0058] like Fig. 9 As shown, this embodiment provides a position calibration method, and the steps of the position calibration method include:

[0059] like Fig. 9 As shown, in step S1, the plane where the flat-panel detector 3 is located is made to receive X-rays vertically; a magnetic field is generated whose central magnetic force lines coincide with the X-rays, and the magnetic induction intensity of the magnetic field is symmetrical based on the X-rays in the cross-section of the X-rays; the magnetic field sensor group 4 is set on the surface of the flat-panel detector 3, and the surface of the flat-panel detector 3 is perpendicular to the X-rays; the magnetic field sensor group 4 is arranged symmetrically based on the geometric center of the surface of the flat-panel detector 3.

[0060] Specifically, in this embodiment, in order to align the X-rays with the geometric center of the surface of the flat panel detector 3, the magnetic field sensor group is arranged symmetrically based on the geometric center of the surface of the flat panel detector 3; wherein the surface of the flat panel detector 3 refers to the surface of the flat panel detector 3 receiving the X-rays and the surface of the flat panel detector 3 that is parallel to the surface receiving the X-rays. Further, a magnetic field is generated in which the central magnetic force line coincides with the X-rays, and the magnetic induction intensity of the magnetic field is symmetrical based on the central magnetic force line in the cross-section of the X-rays; therefore, when the X-rays are aligned with the geometric center of the surface of the flat panel detector 3, it can be observed that the magnetic induction intensity of the magnetic field sensor group is symmetrical based on the X-rays, and the present invention achieves the purpose of aligning the ray source 1 with the geometric center of the surface of the flat panel detector 3.

[0061] like Fig. 9 As shown, in step S2, the position of the ray source 1 and / or the flat panel detector 3 is adjusted so that the X-rays are aligned with the geometric center of the surface of the flat panel detector 3.

[0062] Specifically, in this embodiment, since the X-rays are emitted vertically toward the flat panel detector, in order to quickly align the ray source with the flat panel detector, the position of the ray source 1 and / or the flat panel detector 3 can be adjusted by: translating the ray source 1 in the cross-section of the X-rays (the position of the ray source in the direction of the X-rays remains unchanged) and / or translating the flat panel detector 3 in the cross-section of the X-rays (the position of the flat panel detector in the direction of the X-rays remains unchanged). In practical applications, any moving method that can quickly align the X-rays of the ray source 1 with the flat panel detector 3 is applicable to the present invention, and is not limited to this embodiment.

[0063] Specifically, in this embodiment, when the magnetic induction intensity of the magnetic field sensor group is symmetrical based on X-rays, it is determined that the geometric center of the surface of the flat-panel detector 3 is on the X-rays. In practical applications, the position calibration method of this embodiment can quickly align the ray source with the flat-panel detector by observing the magnetic induction intensity of the magnetic field sensor group. Furthermore, without the need for other auxiliary means, when the magnetic induction intensities detected by magnetic field sensors with equal distances to the geometric center are also equal, it can be considered that the magnetic induction intensity detected by the magnetic field sensor group is symmetrical based on X-rays. Furthermore, if Figure 5 , Figure 6 , Figure 7 and Figure 8 As shown, when the arrangement of each magnetic field sensor to the flat panel detector surface is in an X-shape, a cross, a cross, a rectangle, a circle, a regular hexagon or a regular octagon, when the magnetic induction intensity detected by each magnetic field sensor is symmetrically distributed based on the X-ray, it can be considered that the X-ray is symmetrically aligned with the geometric center of the flat panel detector surface. As an example, Figure 1 As shown, the magnetic field is generated by a square coil, and the X-rays coincide with the central magnetic field lines of the magnetic field, as shown in Figure 5 As shown, the magnetic field sensor group 4 is arranged in a cross shape on the surface of the flat panel detector 3; at the same time, the X-ray is perpendicular to the surface of the flat panel detector, as shown in FIG. Figure 1 As shown, the X-ray can be set to the Z axis, and since the flat panel detector surface is perpendicular to the X-ray, as shown Figure 5As shown, the two sides of the cross can be set as the X-axis and the Y-axis respectively (if it is a cross shape, any two sides of the cross shape can be defined as the X-axis and the Y-axis respectively), so the present invention can quickly establish a coordinate system; on this basis, the position of the ray source 1 is quickly adjusted so that the X-axis and the Y-axis are the symmetry axes of the square coil (when adjusting the position of the circular coil, solenoid, regular hexagonal coil, and regular octagonal coil, the X-axis and the Y-axis should also be the symmetry axes), and then the flat panel detector 3 is moved along the X-axis or the Y-axis to observe whether the magnetic induction intensity of the magnetic field sensor group on the X-axis or the Y-axis is symmetrical; as shown in FIG. Fig.10 As shown in FIG. 1 , when it is observed that the magnetic induction intensity of each magnetic field sensor in the X-axis direction is not symmetrical based on the Z-axis, the position of the ray source and / or the flat panel detector is continued to be moved, such as Fig.11 As shown, it is observed that the magnetic induction intensity of each magnetic field sensor in the X-axis direction is symmetrical based on the Z-axis (that is, the magnetic induction intensity of the first and eighth magnetic field sensors is equal, the magnetic induction intensity of the second and seventh magnetic field sensors is equal, the magnetic induction intensity of the third and sixth magnetic field sensors is equal, and the magnetic induction intensity of the fourth and fifth magnetic field sensors is equal). At this time, it can be considered that the ray source has been aligned with the geometric center of the flat panel detector surface, and there is no need to move the position of the ray source and the flat panel detector. In actual applications, the specific alignment method of the geometric center of the X-ray and the flat panel detector surface is selected according to actual needs, and is not limited to this embodiment.

[0064] In summary, the mobile digital X-ray machine and position calibration method of the present invention include: a ray source, a magnetic field generator, a flat-panel detector and a magnetic field sensor group; first, the X-rays emitted by the ray source are overlapped with the central magnetic field lines of the magnetic field generator; second, the magnetic field sensor group is symmetrically arranged based on the geometric center of the flat-panel detector surface; finally, the position of the ray source and / or the flat-panel detector is adjusted so that the magnetic induction intensity detected by the magnetic field sensor group is symmetrical based on the X-rays, and then the X-rays are aligned with the geometric center of the flat-panel detector surface, so as to achieve the purpose of rapid and accurate alignment of the ray source and the flat-panel detector. In addition, the present invention also has the advantages of simple structure and convenient operation. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has a high industrial utilization value.

[0065] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A mobile digital X-ray machine, characterized in that: The mobile digital X-ray machine at least comprises: a ray source, a magnetic field generator, a flat panel detector and a magnetic field sensor group; The ray source is used to generate X-rays; The magnetic field generator is used to generate a magnetic field, and the central magnetic force lines of the magnetic field generator coincide with the X-rays; Wherein, the magnetic induction intensity in the cross section of the X-ray is symmetric based on the X-ray; The flat panel detector is used to receive the X-rays, and the plane where the flat panel detector is located is perpendicular to the X-rays; The magnetic field sensor group includes n magnetic field sensors, and the n magnetic field sensors are all arranged on the surface of the flat-panel detector, and the surface is perpendicular to the X-ray; the magnetic field sensor group is arranged symmetrically based on the geometric center of the surface; Here, n is a natural number greater than or equal to 2.

2. The mobile digital X-ray machine according to claim 1, characterized in that: The magnetic field generator is any one of a circular coil or a solenoid.

3. The mobile digital X-ray machine according to claim 2, characterized in that: The magnetic field sensor group is arranged on the flat panel detector in an X-shape, a cross-shape or a circle.

4. The mobile digital X-ray machine according to claim 1, characterized in that: The magnetic field generator is any one of a rectangular coil, a regular hexagonal coil or a regular octagonal coil.

5. The mobile digital X-ray machine according to claim 4, characterized in that: The magnetic field sensor group is arranged on the flat panel detector in a cross shape, a cross-shaped shape, a rectangle, a regular hexagon or a regular octagon.

6. A position calibration method, characterized in that: The steps of the position calibration method at least include: S1: Make the plane where the flat panel detector is located receive X-rays vertically; generate a magnetic field whose central magnetic force lines coincide with the X-rays, and the magnetic induction intensity of the magnetic field is symmetrical based on the X-rays in the cross-section of the X-rays; set a magnetic field sensor group on the surface of the flat panel detector, the surface is perpendicular to the X-rays; the magnetic field sensor group is arranged symmetrically based on the geometric center of the surface; S2: Adjust the position of the ray source and / or the flat panel detector so that the geometric center of the surface is on the X-ray.

7. The position calibration method according to claim 6, characterized in that: In step S2, the ray source is translated in the cross-section of the X-ray and / or the flat panel detector is translated in the cross-section of the X-ray to adjust the position of the ray source and / or the flat panel detector.

8. The position calibration method according to claim 6, characterized in that: In step S2, when the magnetic induction intensity of the magnetic field sensor group is symmetric based on the X-ray, it is determined that the geometric center of the surface is on the X-ray.

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