JP4016534B2 - X-ray tomography system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an industrial or medical X-ray tomographic imaging apparatus that captures a tomographic image of a subject.
[0002]
[Prior art]
For example, in an industrial X-ray tomographic imaging apparatus, an object to be inspected (inspection object) placed on a turntable is positioned between an X-ray tube and an X-ray detector arranged to face each other. The turntable (inspection object) is rotated around the rotation center axis of the object to collect X-ray transmission data from the rotation direction of the inspection object, and a tomogram is obtained by a well-known calculation method using the X-ray transmission data. It is configured to reconfigure.
[0003]
In this type of X-ray tomographic imaging apparatus, an X-ray tube, an X-ray detector, and a turntable (inspected) are arranged in a direction in which the tomographic position of the object to be inspected is changed (a direction along the rotation center axis of the turntable). A moving mechanism for relatively moving the body) and tomographic images of various parts of the object to be inspected.
[0004]
By the way, in the calculation for reconstructing the tomogram, the reconstruction parameter is determined by the position of the rotation center axis for rotating the turntable (inspection object), and the tomogram is reconstructed using the reconstruction parameter. Then, regardless of the tomographic position, the tomographic image is reconstructed with the position of the rotation center axis always being the same position.
[0005]
[Problems to be solved by the invention]
However, the conventional example having such a configuration has the following problems.
That is, as shown in FIG. 10A, if the moving direction MY of the moving mechanism is parallel to the rotation center axis J of the turntable 3 (inspection object), the rotation center axis J is There is no particular problem with a conventional apparatus that reconstructs a tomographic image with the position always the same.
[0006]
However, in reality, due to a mechanical error or the like, it is almost impossible to make the moving direction MY of the moving mechanism completely parallel to the rotation center axis J of the turntable 3 (inspected object). As shown in FIG. 10B, when the position of the moving mechanism in the moving direction MY changes, the position of the rotation center axis J changes. Therefore, there is a problem that the tomographic image cannot be reconstructed with an appropriate reconstruction parameter, and the image quality of the reconstructed tomographic image is deteriorated.
[0007]
The present invention has been made in view of such circumstances, and an X-ray tomographic imaging apparatus capable of always reconstructing a high-quality tomographic image by determining the position of an accurate rotation center axis for each tomographic position. The purpose is to provide.
[0008]
[Means for Solving the Problems]
In order to achieve such an object, the present invention has the following configuration.
That is, the present invention includes (1) an X-ray irradiation means for irradiating an object to be inspected with X-rays, and (2) an X-ray that is disposed opposite to the X-ray irradiation means and detects X-ray transmission data of the object to be inspected. And (3) in order to collect X-ray transmission data from the circumferential direction of the object to be inspected, the X-ray irradiation means and the X-ray detection means around the predetermined rotation center axis with respect to the X-ray irradiation means and the X-ray detection means. A rotating means for rotating the inspection object; and (4) a tomographic image reconstruction means for reconstructing a tomographic image of the inspection object using each collected X-ray transmission data from the circumferential direction of the inspection object; (5) An X-ray tomographic imaging apparatus comprising a moving means for relatively moving the X-ray irradiation means, the X-ray detection means, and the inspection object in a direction in which the tomographic position of the inspection object is changed (A) during each rotation at a plurality of detection positions along the moving direction of the moving means. A rotation center axis position detection means for detecting a position of a mandrel; and (b) a position of the rotation center axis at an imaging adjustment position along a moving direction of the movement means when taking a tomographic image. A rotation center axis position determination unit that determines the position based on the position of each rotation center axis at the plurality of detection positions detected by the position detection unit.
[0009]
[Action]
The operation of the present invention is as follows.
Before taking a tomographic image, the rotation center axis position detection means detects the position of each rotation center axis at a plurality of detection positions along the movement direction of the movement means.
[0010]
Thereafter, the moving means relatively moves the X-ray irradiating means, the X-ray detecting means, and the object to be inspected, and the position of the object to be inspected with respect to the X-ray irradiating means and the X-ray detecting means is determined as a tomography at a desired imaging position. Adjust to an imaging adjustment position where an image can be taken.
[0011]
Next, the rotation center axis position determination means determines the position of the rotation center axis at the imaging adjustment position based on the position of each rotation center axis at the plurality of detection positions previously detected by the rotation center axis position detection means. decide.
[0012]
In addition, if the imaging adjustment position exists in a plurality of detection positions where the position of the rotation center axis is detected by the rotation center axis position detection means, the position of the rotation center axis detected with respect to the detection position is It is determined as the position of the rotation center axis at the imaging adjustment position. In addition, if the imaging adjustment position does not exist in the plurality of detection positions, for example, a rotation center axis detected for two detection positions close to the imaging adjustment position in the plurality of detection positions. Are interpolated to determine the position of the rotation center axis at the imaging adjustment position.
[0013]
Then, while irradiating the inspection object from the X-ray irradiation means, the inspection object is rotated with respect to the X-ray irradiation means and the X-ray detection means around the rotation center axis by the rotation means, and the X-ray detector The X-ray transmission data from the rotation direction of the object to be inspected is collected, and the tomographic image reconstruction means reconstructs the tomographic image of the inspection object using the collected X-ray transmission data from the rotation direction of the inspection object Then, a tomographic image is taken. At this time, the reconstruction parameter used for reconstruction of the tomographic image is determined by the position of the rotation center axis at the imaging adjustment position determined by the rotation center axis position determination means.
[0014]
Thereafter, the adjustment to the imaging adjustment position according to the tomographic position by the moving means described above, the determination of the position of the rotation center axis at the imaging adjustment position by the rotation center axis position determining means, and the imaging of the tomographic image are switched back to a plurality of tomographic images. Images can be taken continuously.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of an X-ray tomographic imaging apparatus according to an embodiment of the present invention, and FIG. 2 is a plan view of an X-ray tube, an X-ray detector and a turntable. In each figure, XYZ orthogonal coordinates for indicating the positional relationship of each component device are attached.
[0016]
This embodiment is an industrial X-ray tomographic imaging apparatus for capturing a tomographic image of an object to be inspected (inspected object) M, and includes an X-ray tube 1 and an X-ray detecting means corresponding to X-ray irradiation means. The corresponding X-ray detection unit 2 is arranged oppositely and fixed, and the inspection object M placed on the turntable 3 can be arranged between the X-ray tube 1 and the X-ray detector 2. Has been.
[0017]
The X-ray tube 1 is configured so that required power is supplied from an X-ray high voltage generator (not shown) and radiates radial X-rays toward the X-ray detector 2.
[0018]
The X-ray detector 2 is an image intensifier (I) that two-dimensionally detects X-ray transmission data irradiated from the X-ray tube 1 and transmitted through the object M to be converted into a two-dimensional visible image of visible light. I) 4 and I.4. Two-dimensional X-ray transmission data of the object M to be inspected, including an imaging device 5 such as a CCD camera for imaging a two-dimensional perspective image of visible light converted by I4 via an optical system (not shown). Is detected and output as an electric signal (video signal such as an NTSC signal). The electrical signal output from the X-ray detection unit 2 is converted into digital data by an A / D (analog to digital) converter 6 and then stored in the X-ray detection data storage unit 7.
[0019]
The turntable 3 is configured to be movable (lifted / lowered) in the Z direction in the figure by a Z direction moving mechanism 8 corresponding to a moving means, and arbitrarily changes the tomographic position of the inspection object M placed on the turntable 3. It is configured to be adjustable. The turntable 3 is configured to be rotatable around a rotation center axis J parallel to the Z direction by a motor 9 corresponding to a rotating means. The Z-direction moving mechanism 8 and the motor 9 are controlled by a movement / rotation control unit 10. The movement / rotation control unit 10 drives the Z-direction movement mechanism 8 based on the imaging adjustment position set from the operation unit 11 or the detection position stored in the detection position storage unit 12, and turns the turntable to the set position. 3 is moved, and an arbitrary tomographic position of the inspection object M placed on the turntable 3 is arranged at the imaging position. In addition, the movement / rotation control unit 10 drives the motor 9 according to an instruction from the operation unit 11 to rotate the turntable 3 (inspected object M, phantom F, which will be described later) around the rotation center axis J.
[0020]
From the operation device 11, it is possible to set a tomographic width at the time of capturing a tomographic image, an instruction to detect each rotation center axis position at a plurality of detection positions, an instruction to image a tomographic image, and the like.
[0021]
The detection position storage unit 12 stores a plurality of detection positions. The plurality of detection positions stored in the detection position storage unit 12 can be set, added, changed, deleted, etc. from the operation device 11.
[0022]
The rotation center axis position detection unit 13 detects the position of the rotation center axis J at the detection position by a method described later every time the turntable 3 is positioned at each detection position stored in the detection position storage unit 12. . The detected position of each rotation center axis J for each detected position is stored in the rotation center axis position storage unit 14 in association with each detected position.
[0023]
The movement / rotation control unit 10, the detection position storage unit 12, the rotation center position detection unit 13, and the like constitute rotation center position detection means in the present invention.
[0024]
The rotation center position determination unit 15 corresponding to the rotation center axis position determination means determines the position of the rotation center axis J at the position in the Z direction (imaging adjustment position) of the turntable 3 when capturing a tomographic image. Based on the data stored in the storage unit 14, the determination is made as described later.
[0025]
As will be described later, the tomogram reconstruction unit 16 corresponding to the tomogram reconstruction unit uses two-dimensional X-ray transmission data from the circulation direction of the object M collected in the X-ray detection data storage unit 7 as described later. A tomographic image is reconstructed by a known calculation method. When the tomographic image is reconstructed, the tomographic image is reconstructed by determining the reconstruction parameter based on the position of the rotation center axis J at the imaging adjustment position at the time of capturing the tomographic image determined by the rotational center position determining unit 15. To do. For example, the reconstructed tomographic image is stored in the tomographic image storage unit 17 or displayed on the image monitor 18.
[0026]
Note that the X-ray detection unit 2 of this embodiment collects two-dimensional X-ray transmission data from the circulation direction of the subject M, but X-ray transmission data used for reconstruction of tomographic images is two-dimensional. This is a part of the X-ray transmission data. This will be described next.
[0027]
In this embodiment, as shown in FIG. 3, the imaging position is determined so that the X-ray XC irradiated in the horizontal direction from the X-ray tube 1 coincides with the center position CL of the tomographic image. The X-ray XC irradiated from the X-ray tube 1 in the horizontal direction is The height positions of the X-ray tube 1 and the X-ray detector 2 are adjusted so as to coincide with the center position ICL in the Z direction on the detection surface 4a of I4.
[0028]
As shown in FIG. 3, the tomographic width DH set from the operation unit 11 is I.I. The tomographic region IH projected on the detection surface 4a of I4 is obtained by the following equation (1) by a proportional relationship.
[0029]
IH = (DH × LA) / LD (1)
[0030]
In the above formula (1), DH is a set value (set value of tomographic width). LA is the X-ray focal point XP of the X-ray tube 1 and I.I. The distance between the detection surface 4a of I4 and LD is the distance from the X-ray focal point XP of the X-ray tube 1 to the set tomographic width DH in the inspected object M, both of which are known. Therefore, the set fault width DH is I.I. The tomographic region IH projected on the detection surface 4a of I4 can be obtained.
[0031]
Of the digital two-dimensional X-ray transmission data XD collected in the X-ray detection data storage unit 7, the X-ray transmission data in the pixel region GH corresponding to the tomographic region IH indicated by the oblique lines in FIG. Used for image reconstruction. Note that the symbol GC in FIG. A pixel row corresponding to the center position ICL in the Z direction on the detection surface 4a of I4 is shown. In addition, when the two-dimensional X-ray transmission data detected by the X-ray detection unit 2 has distortion or the like, an area slightly wider than the pixel area GH shown in FIG. The tomographic image may be reconstructed using the X-ray transmission data in ().
[0032]
Each of the storage units 7, 12, 14 and the movement / rotation control unit 10, the operation unit 11, the rotation center axis position detection unit 13, the rotation center position determination unit 15, the tomographic image reconstruction unit 16, and the like are, for example, a personal computer. The process control configured and executed by each unit is realized by software.
[0033]
Next, the operation of the above apparatus will be described.
First, before taking a tomographic image, the position of each rotation center axis J at a plurality of detection positions along the Z direction of the turntable 3 is detected.
[0034]
For example, a phantom F as shown in FIG. 5 is used to detect the position of each rotation center axis J at each detection position. In this phantom F, a linear subject 21 is accommodated in a case 20. As shown in FIG. 5, the operator places the phantom F on the turntable 3 with the subject 21 parallel to the Z direction, and the position of each rotation center axis J at the plurality of detection positions from the operation device 11. Instruct detection.
[0035]
Thereby, the movement rotation control part 10 reads each detection position memorize | stored in the detection position memory | storage part 12 one by one, and makes the turntable 3 position in each detection position sequentially.
[0036]
Here, it is assumed that the respective detection positions stored in the detection position storage unit 12 are the three positions P1 to P3 shown in FIG.
[0037]
When the turn table 3 is positioned at the first detection position P1, the movement / rotation control unit 10 drives the motor 9 to rotate the turn table 3 around the rotation center axis J. As the turntable 3 rotates, X-rays are emitted from the X-ray tube 1, and the X-ray transmission data of the phantom F (subject 21) for one rotation of the turntable 3 is detected by the X-ray detector 2. Collected in the detection data storage unit 7.
[0038]
When attention is paid to the X-ray transmission data of the pixel column GC shown in FIG. 4 among the X-ray transmission data of the phantom F (subject 21) for one rotation of the turntable 3 collected in the X-ray detection data storage unit 7, 1 The X-ray transmission data of the rotated pixel column GC is as shown in FIG.
[0039]
FIG. 7A shows a case where the subject 21 coincides with the rotation center axis J, and FIG. 7B shows a case where the subject 21 deviates from the rotation center axis J.
[0040]
In the case of FIG. 7A, the position of the rotation center axis J is j1 shown in FIG. On the other hand, in the case of FIG. 7B, the center position (j1 shown in FIG. 7B) of the fluctuation range R of the subject 21 that has changed in the horizontal direction during one turn of the turntable 3 is the position of the rotation center axis J. And
[0041]
When the rotation center axis position detection unit 13 detects the position (j1) of the rotation center axis J at the first detection position P1 as described above, the rotation center axis position detection unit 13 stores it in the rotation center axis position storage unit 14, and similarly, the detection position P2 , The position of the rotation center axis J at P3 is sequentially detected and stored in the rotation center axis position storage unit 14.
[0042]
The storage state of the rotation center axis position storage unit 14 in the state where the detection of the position of the rotation center axis J at all the detection positions P1 to P3 is completed, and the position (j1) of each rotation center axis J at each detection position P1 to P3. An example of the positional relationship of .about.j3) is shown in FIG.
[0043]
When the detection of the position of each rotation center axis J at the plurality of detection positions is completed, a tomographic image is next captured.
[0044]
That is, first, the operator places the inspection object M on the turntable 3 instead of the phantom F, sets the tomographic width DH from the operating device 11, and sets the imaging adjustment position of the turntable 3. The tomographic width DH is given to the tomographic image reconstruction unit 16, and the imaging adjustment position is given to the movement rotation control unit 10 and the rotation center axis position determination unit 15. When the imaging adjustment position is given, the movement / rotation control unit 10 drives the Z-direction moving mechanism 8 to position the turntable 3 at the imaging adjustment position, and the tomographic position of the object M to be inspected accordingly is taken as the imaging position. To be located. When the turntable 3 is located at the imaging adjustment position, the operator instructs the operator 11 to capture a tomographic image. Thereby, as will be described later, a tomographic image of a tomographic position corresponding to the current imaging adjustment position is captured. When the imaging of one tomographic image is completed, the operator sets the next imaging adjustment position from the operation device 11, and when the turntable 3 is positioned at the imaging adjustment position, the operator performs imaging of the tomographic image from the operation device 11. By repeating the instruction, it is possible to continuously capture tomographic images at a plurality of tomographic positions.
[0045]
Here, it is assumed that five tomographic images having a tomographic width DH at the imaging adjustment positions H1 to H5 (tomographic positions D1 to D5) as shown in FIG. 9 are taken.
[0046]
When imaging of the tomographic image is instructed from the operation unit 11, the two-dimensional X-ray transmission data from the circulation direction of the object M is collected in the X-ray detection data storage unit 7, while the rotation center axis position determination unit 15. Determines the position of the rotation center axis J at the current imaging adjustment position.
[0047]
That is, the X-ray tube 1 irradiates the subject M with X-rays, the motor 9 is driven and the turntable 3 is rotated around the rotation center axis J, and the X-ray detector 2 circulates the subject M. Two-dimensional X-ray transmission data from the direction is detected and collected in the memory 7.
[0048]
On the other hand, the rotation center axis position determination unit 15, if the imaging adjustment position exists in the plurality of detection positions P1 to P3 that previously detected the position of the rotation center axis J as in H3, is set to the detection position P2. The detected position j2 of the rotation center axis J is determined as the position of the rotation center axis J at the imaging adjustment position H3. Further, if there is no imaging adjustment position among the plurality of detection positions P1 to P3 as in H1, H2, H4, and H5, the imaging adjustment positions H1 and H2 among the plurality of detection positions P1 to P3. , H4 and H5 are interpolated between the positions of the rotation center axis J detected with respect to the two detection positions (H1 and H2 are P1 and P2, H4 and H5 are P2 and P3), and the imaging adjustment positions H1 and H2 , H4, and H5 are determined as the positions of the rotation center axis J.
[0049]
The above interpolation is calculated by linear interpolation or the like. For example, the position (jH1) of the rotation center axis J at the imaging adjustment position H1 is obtained by the following equation (2).
[0050]
jH1 = j1 + {(H1-P1) × (j2-j1) / (P2-P1)} (2)
Note that P1 <P2.
[0051]
The position of the rotation center axis J at the imaging adjustment position H2 may be obtained by replacing “H1” in the above formula (2) with “H2”. The position of the rotation center axis J at the imaging adjustment positions H4 and H5 is “j1” in the above formula (2) as “j2”, “j2” and “j3”, “P1” as “P2”, “ Instead of “P2” and “33”, “H1” may be replaced with “H4” and “H5”.
[0052]
When the X-ray transmission data is collected in the X-ray detection data storage unit 7 and the position of the rotation center axis J at the current imaging adjustment position is determined, the tomographic image reconstruction unit 16 collects the data in the X-ray detection data storage unit 7. A tomographic image is reconstructed based on the obtained X-ray transmission data and the position of the rotation center axis J at the current imaging adjustment position.
[0053]
As described above, according to this embodiment, the Z-direction moving mechanism for detecting the positions of the respective rotation center axes J at a plurality of detection positions along the moving direction of the Z-direction moving mechanism 8 and capturing a tomographic image. Since the position of the rotation center axis J at the imaging adjustment position along the movement direction of 8 is determined based on the position of each rotation center axis J at the plurality of previously detected detection positions, it is always accurate at any tomographic position. A tomographic image can be reconstructed based on the position of the rotation center axis J, and a high-quality tomographic image can be obtained.
[0054]
Further, according to this embodiment, since the positions of the respective rotation center axes J at the plurality of detection positions are detected, it is possible to subsequently capture tomographic images at a plurality of tomographic positions. Therefore, for example, each time a tomographic image is taken, the labor of the operator is reduced compared with the case where the tomographic image is taken after detecting the position of the rotation center axis J at the tomographic position of the tomographic image. You can also
[0055]
Incidentally, the plurality of detection positions may coincide with the imaging adjustment position corresponding to the tomographic position of the next tomographic image to be imaged. However, as described above, the position of the rotation center axis J at the imaging adjustment position may be obtained by interpolation. Therefore, the plurality of detection positions can be adopted at arbitrary positions regardless of the imaging adjustment position corresponding to the tomographic position of the tomographic image to be imaged next. Therefore, if the position of each rotation center axis J at a plurality of representative detection positions is detected, an accurate position of the rotation center axis J can be obtained even if a tomographic image at an arbitrary tomographic position is taken, and high image quality can be obtained. A tomographic image can be obtained.
[0056]
In the above-described embodiment, for example, the position of each rotation center axis J at a plurality of detection positions is detected before the tomographic image of the inspection object M is captured every time the inspection object M is changed. .
[0057]
Moreover, in the said Example, although comprised so that a some detection position was memorize | stored in the detection position memory | storage part 12, it is the rotation center axis | shaft J in each detection position, setting each detection position from the operation device 11 grade | etc.,. You may comprise so that a position may be detected sequentially.
[0058]
Furthermore, in the above-described embodiment, the imaging adjustment positions are sequentially set by the operator 11 while the operator sets the imaging adjustment positions, and the tomographic images at the respective tomographic positions are sequentially picked up. You may comprise so that the tomogram of the tomographic position according to each imaging adjustment position may be automatically performed. In this case, when a plurality of imaging adjustment positions are set together, the position of each rotation center axis J at each imaging adjustment position may be determined collectively.
[0059]
Instead of setting each imaging adjustment position, a plurality of imaging adjustment positions may be set by setting an initial imaging adjustment position and a movement pitch.
[0060]
Further, in the above-described embodiment, the turntable 3 is configured to be movable only in the Z direction. In addition, the turntable 3 is configured to be movable in the X direction and the Y direction. You may comprise so that the position of the to-be-inspected object M mounted in the turntable 3 between the detection parts 2 can also be changed to a X direction or a Y direction. In this configuration, after the position of the turntable 3 in the X direction and the Y direction is adjusted, the position of each rotation center axis J at a plurality of detection positions is detected, and then a tomographic image is taken. Good.
[0061]
In the above embodiment, I.I. Although the X-ray detection means is configured by I4 and the image pickup device 5 and the like, the present invention is not limited to this. For example, the X-ray detection means may be constituted by a flat panel type X-ray sensor that detects X-ray transmission data two-dimensionally and directly converts the detection data into an electrical signal for each pixel. The line detection means is not limited to one that can detect X-ray transmission data two-dimensionally, but may be one that can detect X-ray transmission data one-dimensionally.
[0062]
Furthermore, in the above-described embodiment, the position of the rotation center position J at each detection position is detected using the phantom F shown in FIG. 5, but the position of the rotation center position J at each detection position is detected with other configurations. You may go.
[0063]
Moreover, in the said Example, although comprised so that the to-be-inspected object M side might be moved to the direction (Z direction) which changes a tomographic position with respect to the X-ray tube 1 and the X-ray detection part 2, On the other hand, the present invention can be similarly applied to an apparatus configured to move the X-ray tube 1 and the X-ray detection unit 2 side in the direction (Z direction) in which the tomographic position of the object M is changed.
[0064]
Further, in the above-described embodiment, the inspection object is the inspection object M, and an industrial X-ray tomographic imaging apparatus that captures a tomographic image for inspecting the inside of the inspection object has been described as an example. The present invention can also be applied to the case where a tomographic image for medical diagnosis is taken as the inspection object M.
[0065]
【The invention's effect】
As is apparent from the above description, according to the present invention, the position of the rotation center axis at a plurality of detection positions along the moving direction of the moving means is detected, and the moving means for capturing a tomographic image is detected. Since the position of the rotation center axis at the imaging adjustment position along the moving direction is determined based on the position of each rotation center axis at a plurality of previously detected detection positions, the rotation center axis is always accurate at any tomographic position. The tomographic image can be reconstructed based on the position of, and a high-quality tomographic image can be obtained.
[0066]
In addition, since the positions of the respective rotation center axes at the plurality of detection positions are detected, it is possible to continuously capture tomographic images at a plurality of tomographic positions. For example, each time one tomographic image is captured. Compared to the case where the tomographic image is picked up after detecting the position of the rotation center axis at the tomographic position of the tomographic image, it is possible to reduce the labor of the operator.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration of an X-ray tomographic imaging apparatus according to an embodiment of the present invention.
FIG. 2 is a plan view of an X-ray tube, an X-ray detector, and a turntable.
FIG. 3 is a diagram for explaining an X-ray transmission data portion used for reconstruction of a tomographic image in two-dimensional X-ray transmission data.
FIG. 4 is a diagram showing an X-ray transmission data portion used for reconstruction of a tomographic image in two-dimensional X-ray transmission data.
FIG. 5 is a perspective view showing a phantom used for detection of each rotation center axis position at a plurality of detection positions.
FIG. 6 is a diagram illustrating an example of a plurality of detection positions.
FIG. 7 is a diagram illustrating a method of detecting the position of the rotation center axis at each detection position.
FIG. 8 is a diagram illustrating an example of a storage state of a rotation center axis position storage unit after detecting a position of a rotation center axis at each detection position and a positional relationship between positions of the rotation center axes at each detection position; .
FIG. 9 is a diagram illustrating an example of an imaging adjustment position.
FIG. 10 is a diagram for explaining a problem of a conventional device.
[Explanation of symbols]
1: X-ray tube 2: X-ray detection unit 3: Turntable 4: Image intensifier 5: Imager 7: X-ray detection data storage unit 8: Z-direction moving mechanism 9: Motor 10: Moving rotation control unit 11: Controller 12: Detection position storage unit 13: Rotation center axis position detection unit 14: Rotation center axis position storage unit 15: Rotation center axis position determination unit 16: Tomographic reconstruction unit M: Inspected object J: Rotation center axis P1 to P1 P3: A plurality of detection positions j1 to j3: Positions H1 to H5 of each rotation center axis at each detection position: Each imaging adjustment position D1 to D5: A tomographic position of the object to be inspected according to each imaging adjustment position

Claims (1)

(1) X-ray irradiation means for irradiating the object to be inspected with X-rays, (2) X-ray detection means for detecting X-ray transmission data of the object to be inspected, disposed opposite to the X-ray irradiation means, 3) Rotation of rotating the inspection object relative to the X-ray irradiation means and the X-ray detection means around a predetermined rotation center axis in order to collect X-ray transmission data from the rotating direction of the inspection object Means, (4) tomographic image reconstruction means for reconstructing a tomographic image of the object to be inspected using each collected X-ray transmission data from the circulation direction of the object to be inspected, and (5) the object to be inspected An X-ray tomographic imaging apparatus comprising: a moving unit that relatively moves the X-ray irradiation unit, the X-ray detection unit, and the subject to be examined in a direction in which a tomographic position of a body is changed; A rotation detecting position of each rotation center axis at a plurality of detection positions along the moving direction of the moving means. A rotation center axis position detection unit; and (b) a position of the rotation center axis at an imaging adjustment position along a moving direction of the movement unit when capturing a tomographic image is detected by the rotation center axis position detection unit. An X-ray tomographic imaging apparatus comprising: a rotation center axis position determining unit that determines a position based on the position of each rotation center axis at the plurality of detection positions.

Images