Radiography apparatus, image generation method, radiation photography system, and program

Abstract

To make an accurate adjustment of positions with no displacements of separately taken images of an object that is beyond the size of a single imaging and has no unique features.SOLUTION: A radioactive imaging device includes: generation means (a control unit 51) having a radioactive source, a plurality of lattices, and a radioactive detector which are lined in the direction of a radiation application axis, the generation means generating a re-configuration image on the basis of a moire fringe image obtained by irradiating an object arranged in a position overlapping with the direction of the radiation application axis, with radiation, from the radiation source and performing imaging; acquisition means (a control unit 51) for acquiring relative position information on a relative position in at least two-dimension of the object to the lattices; and control means (a control unit 51) for relating relative position information and the re-configuration image to each other.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a radiographic apparatus, an image generating method, a radiographic system, and a program. [Background technology]

[0002] Conventionally, X-ray imaging devices using a Talbot interferometer or Talbot-Lau interferometer with multiple gratings (hereinafter referred to as X-ray Talbot imaging devices) have been known. In X-ray Talbot imaging devices, the imaging range is determined by the size (area) of the gratings. However, manufacturing gratings is difficult, and increasing their size is also extremely difficult. Therefore, when imaging an object larger than the imaging range of a single shot, it is necessary to photograph the object while shifting its position, and then align the images using image processing and combine the images. Orientation photography is also being performed, in which multiple images of different orientations relative to the lattice are taken by rotating the object, and then image processing is performed to derive information such as the degree of orientation that cannot be determined from each image alone. Then, image processing is used to correct the positional deviation that occurs when the object is rotated, and alignment is performed.

[0003] Regarding alignment, the invention described in Patent Document 1 performs alignment using an absorption image. In addition, alignment is generally performed using a marker made of a material (such as lead) that has a high X-ray absorption rate. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6780591 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the subject is too large to fit within a single shooting range and is a flat plate without any major features, it is difficult to perform accurate alignment. In the alignment method described in Patent Document 1, alignment is performed by matching pixels in the absorption image, but in the case of a flat plate without any major features, there may be a misalignment of several pixels. Furthermore, when markers are used, there is a problem that the markers are reflected in the captured image, causing defects.

[0006] Therefore, an object of the present invention is to provide a radiographic imaging device, an image generation method, a radiographic imaging system, and a program that can align images captured multiple times with high precision, even for subjects that do not have significant features on the image and whose size exceeds the range of a single imaging session. [Means for solving the problem]

[0007] In order to solve the above problems, the radiation imaging apparatus of the present invention comprises: a generating means for generating a reconstructed image based on a Moiré fringe image obtained by irradiating a subject, which is disposed at a position overlapping with the radiation irradiation axis direction, with radiation from the radiation source and photographing the subject; and an acquisition means for acquiring relative position information that is a relative position of the subject with respect to the grid in two or more dimensions; a control means for linking the relative position information with the reconstructed image; Equipped with 、 The control means determines whether or not photography is possible based on information about the material and / or composition of the subject and information about the thickness of the subject obtained from the relative position information. do. The radiation imaging apparatus of the present invention further comprises: a generating means for generating a reconstructed image based on a Moiré fringe image obtained by irradiating a subject, which is disposed at a position overlapping with the radiation irradiation axis direction, with radiation from the radiation source and photographing the subject; and an acquisition means for acquiring relative position information that is a relative position of the subject with respect to the grid in two or more dimensions; a control means for linking the relative position information with the reconstructed image; Equipped with The control means derives photographing conditions from information on the material and / or composition of the subject and information on the thickness of the subject obtained from the relative position information.

[0008] Further, the image generating method of the present invention includes: a generating means for generating a reconstructed image based on a Moiré fringe image obtained by irradiating a subject placed at a position overlapping with the radiation irradiation axis direction with radiation from the radiation source and capturing the image, the generating means including a radiation source, a plurality of gratings, and a radiation detector arranged in a line in the radiation irradiation axis direction; acquiring relative position information, which is a relative position of the subject relative to the grid in two or more dimensions, by an acquisition means; The control means links the relative position information with the reconstructed image. 、 The control means determines whether or not photography is possible based on information about the material and / or composition of the subject and information about the thickness of the subject obtained from the relative position information. do. Further, the image generating method of the present invention includes: a generating means for generating a reconstructed image based on a Moiré fringe image obtained by irradiating a subject placed at a position overlapping with the radiation irradiation axis direction with radiation from the radiation source and capturing the image, the generating means including a radiation source, a plurality of gratings, and a radiation detector arranged in a line in the radiation irradiation axis direction; acquiring relative position information, which is a relative position of the subject relative to the grid in two or more dimensions, by an acquisition means; linking the relative position information with the reconstructed image by a control means; The control means derives photographing conditions from information on the material and / or composition of the subject and information on the thickness of the subject obtained from the relative position information.

[0009] The radiation imaging system of the present invention further comprises: the radiation imaging device; a device for outputting image data that allows the photographing range and the subject to be grasped in the same coordinate system; A radiography system comprising: The analysis results of the device and the reconstructed image are collated in terms of position using the relative position information.

[0010] The radiation imaging system of the present invention further comprises: A radiation imaging system including the radiation imaging apparatus, Using the relative position information, the reconstructed image and the optical image obtained by the imaging means are displayed in an overlapping manner.

[0011] The program of the present invention also includes: A computer of a radiographic apparatus in which a radiation source, a plurality of gratings, and a radiation detector are arranged in a direction of a radiation irradiation axis, a generating means for generating a reconstructed image based on a moiré fringe image obtained by irradiating radiation from the radiation source onto a subject disposed at a position overlapping with the radiation irradiation axis direction and performing imaging; an acquisition means for acquiring relative position information that is a relative position of the subject with respect to the grid in two or more dimensions; The relative position information is linked to the reconstructed image. 、 The control means determines whether or not photography is possible based on information about the material and / or composition of the subject and information about the thickness of the subject obtained from the relative position information. do. The program of the present invention also includes: A computer of a radiographic apparatus in which a radiation source, a plurality of gratings, and a radiation detector are arranged in a direction of a radiation irradiation axis, a generating means for generating a reconstructed image based on a moiré fringe image obtained by irradiating radiation from the radiation source onto a subject disposed at a position overlapping with the radiation irradiation axis direction and performing imaging; an acquisition means for acquiring relative position information that is a relative position of the subject with respect to the grid in two or more dimensions; functioning as a control means for linking the relative position information with the reconstructed image; The control means derives photographing conditions from information on the material and / or composition of the subject and information on the thickness of the subject obtained from the relative position information. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a radiographic imaging device, an image generation method, a radiographic imaging system, and a program that can align images captured multiple times with high precision, even when there are no significant features on the image and the subject is larger than the range of a single imaging session. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a diagram showing an example of the arrangement of an X-ray Talbot imaging apparatus according to a first embodiment. [Figure 2] FIG. 2 is a plan view of a multi-slit. [Figure 3] FIG. 2 is a block diagram showing the functional configuration of a controller. [Figure 4] FIG. 1 is a diagram illustrating the principle of a Talbot interferometer. [Figure 5] 10 is a flowchart showing an image capturing process a executed in the first embodiment (Example 1). [Figure 6] FIG. 2 is a diagram illustrating the relationship between a subject and a photographing position in the first embodiment (Example 1). [Figure 7] FIG. 10 is a diagram illustrating the relationship between a subject and a photographing position in the second embodiment. [Figure 8] FIG. 11 is a diagram showing the relationship between a subject and a photographing position in the third embodiment. [Figure 9]FIG. 10 is a diagram showing the relationship between parent samples and child samples in Example 4. [Figure 10] 13 is a flowchart showing a photographing possibility determination process b executed in the fifth embodiment. [Figure 11] 10 is an example of deriving a position correction amount. [Figure 12] FIG. 10 is a diagram illustrating an example of the configuration of an X-ray Talbot imaging apparatus according to a second embodiment. [Figure 13] 10 is a display example 1 in the second embodiment. [Figure 14] 10 is a display example 2 in the second embodiment. [Figure 15] FIG. 10 is a diagram illustrating an example of the configuration of an X-ray Talbot imaging apparatus according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, although the embodiments described below are subject to various technically preferable limitations for carrying out the present invention, the technical scope of the present invention is not limited to the following embodiments and illustrated examples.

[0015] [First embodiment] (Configuration of Radiography System) FIG. 1 is a diagram schematically showing an X-ray Talbot imaging apparatus 100 according to a first embodiment of the present invention.

[0016] As shown in FIG. 1, the X-ray Talbot imaging device 100 includes a main body 1 and a controller 5. As shown in Fig. 1, the main body 1 includes a radiation source 11, a first cover unit 120 including a multi-slit 12 and an additional filter / collimator 112, a second cover unit 130 including a subject table 13, a first grating 14, a second grating 15, and a radiation detector 16, a support 17, and a base 19. The Talbot-Lau interferometer of the main body 1 is vertical, and the radiation source 11, the multi-slit 12, the subject table 13, the first grating 14, the second grating 15, and the radiation detector 16 are arranged in this order in the z direction, which is the direction of gravity (vertical). A camera 21 is provided outside the X-ray irradiation range.

[0017] The multi-slit 12, the subject table 13, the first grating 14, the second grating 15, and the radiation detector 16 are held by the same base unit 19 and attached to a support 17. The base unit 19 may be configured to be movable in the z-direction relative to the support 17. In addition to the base 19, the radiation source 11 is also attached to the support 17. The radiation source 11 is held by the support 17 via a buffer member 17a. The buffer member 17a may be made of any material that can absorb shock and vibration, and examples thereof include elastomer. Because the radiation source 11 generates heat when irradiated with radiation, it is preferable that the buffer member 17a on the radiation source 11 side is also made of a heat insulating material.

[0018] The radiation source 11 includes an X-ray tube that generates X-rays and irradiates them in the z direction (the direction of gravity). The X-ray tube may be, for example, a Coolidge X-ray tube or a rotating anode X-ray tube. The anode may be made of tungsten or molybdenum. The focal diameter of the radiation source 11 is preferably 0.03 to 3 (mm), and more preferably 0.1 to 1 (mm). In this embodiment, an example will be described in which imaging is performed using X-rays, but other radiation such as neutron rays or gamma rays may also be used.

[0019] The first cover unit 120 is a unit provided directly below the radiation source 11. As shown in Fig. 1, the first cover unit 120 is configured to include a multi-slit 12, an attachment arm 12b, an additional filter / collimator 112, etc. Each component of the first cover unit 120 is covered and protected by a cover member.

[0020] The multi-slit 12 (G0 grating) is a diffraction grating, and as shown in Figure 2, it has multiple slits arranged at a predetermined interval in the x-direction, which is perpendicular to the radiation irradiation axis direction (here, the z-direction). The multi-slit 12 is formed from a material with high radiation shielding properties, i.e., high radiation absorption, such as tungsten, lead, or gold, on a substrate made of a material with low radiation absorption, such as silicon or glass. For example, a resist layer is masked with slits using photolithography, and UV light is irradiated to transfer the slit pattern onto the resist layer. A slit structure with the same shape as the pattern is obtained by exposure, and metal is then filled in between the slit structures by electroforming, forming the multi-slit 12.

[0021] The slit period (grating period) of the multi-slit 12 is 1 to 60 μm. As shown in FIG. 2, the distance between adjacent slits is defined as one period. The slit width (the length of each slit in the slit period direction (x direction)) is 1 to 60% of the slit period, and more preferably 10 to 40%. The slit height (height in the z direction) is 1 to 1500 μm, and preferably 30 to 1000 μm. The multi-slit 12 is supported by a mounting arm 12b and attached to a base 19. The multi-slit 12 (G0 grating) may be omitted if the focal point of the X-ray tube of the radiation source 11 is small, such as in a microfocus radiation source.

[0022] The additional filter collimator 112 limits the irradiation area of ​​the X-rays emitted from the radiation source 11 and removes low energy components from the X-rays emitted from the radiation source 11 that do not contribute to imaging.

[0023] 1, the second cover unit 130 is configured to include the subject table 13, the first grating 14 and the second grating 15, a moving mechanism 15a, a radiation detector 16, etc. The upper surface of the second cover unit 130 is the subject table 13, and by covering the periphery of the subject table 13 with a cover member, the internal components are protected from damage caused by contact with the subject H or an engineer and from the intrusion of dust. In addition, because the temperature inside the unit is less susceptible to the influence of the outside air, fluctuations in the grating position due to thermal expansion of the first grating 14 and the second grating 15 can be reduced.

[0024] The subject table 13 is a table on which the subject H is placed. The subject table 13 is movable in two dimensions and in rotation (XY axes and Θ axis).

[0025] The first grating 14 (G1 grating), like the multi-slit 12, is a diffraction grating in which multiple slits are arranged in the x-direction perpendicular to the z-direction, which is the radiation irradiation axis direction. The first grating 14 can be formed by UV photolithography, like the multi-slit 12, or by forming a grating structure solely from silicon by deep etching a silicon substrate with fine wires using the so-called ICP method. The slit period of the first grating 14 is 1 to 20 μm. The slit width is 20 to 70% of the slit period, preferably 35 to 60%. The slit height is 1 to 100 μm.

[0026] Similar to the multi-slit grating 12, the second grating 15 (G2 grating) is a diffraction grating in which multiple slits are arranged in the x-direction perpendicular to the z-direction, which is the radiation irradiation axis direction. The second grating 15 can also be formed by photolithography. The slit period of the second grating 15 is 1 to 20 μm. The slit width is 30 to 70% of the slit period, and preferably 35 to 60%. The slit height is 1 to 100 μm. A moving mechanism 15a that moves the second grating 15 in the x-direction is provided adjacent to the second grating 15. The moving mechanism 15a may have any configuration as long as it can linearly move the second grating 15 in the x-direction by driving a motor or the like.

[0027] The radiation detector 16 has conversion elements arranged two-dimensionally, which generate electrical signals in response to irradiated radiation, and reads the electrical signals generated by the conversion elements as image signals. The pixel size of the radiation detector 16 is 10 to 300 (μm), and more preferably 50 to 200 (μm). The radiation detector 16 is preferably fixed in position on the base part 19 so as to abut against the second grating 15. This is because the greater the distance between the second grating 15 and the radiation detector 16, the more blurred the moiré fringe image obtained by the radiation detector 16.

[0028] A flat panel detector (FPD) can be used as the radiation detector 16. FPDs include an indirect conversion type that converts radiation into an electric signal using a photoelectric conversion element via a scintillator, and a direct conversion type that directly converts radiation into an electric signal, and either type may be used. Furthermore, a radiation detector that is given the intensity modulation effect of the second grating 15 may be used as the radiation detector 16. For example, a slit scintillator detector in which grooves are carved into the scintillator to form a grid-shaped scintillator may be used as the radiation detector 16 in order to give the scintillator dead regions with the same period and width as the slits of the second grating 15. In this case, the radiation detector 16 combines the second grating 15 and the radiation detector 16, so there is no need to provide a separate second grating 15. In other words, providing a slit scintillator detector is the same as providing both the second grating 15 and the radiation detector 16.

[0029] The Talbot-Lau interferometer of the main body 1 has been described as being configured to irradiate X-rays from the radiation source 11 provided on the upper side toward the subject H below (a so-called vertical type), but the present invention is not limited to this and may be configured to irradiate X-rays from the radiation source 11 provided on the lower side toward the subject H above. It is also possible to configure the interferometer to irradiate X-rays in any direction, such as horizontally (a so-called horizontal type).

[0030] The camera 21 is capable of acquiring images including depth information and is an RGB-D camera (Red Green Blue-Depth camera) that can obtain RGB-D images including three-dimensional point cloud data. In other words, the camera 21 is capable of acquiring three-dimensional information and RGB images (two-dimensional images). Furthermore, the camera 21 is adjusted to match the absolute position of the X-ray Talbot imaging device 100 (G0 lattice, G1 lattice, G2 lattice). Specifically, the coordinates of the RGB-D image captured by the camera 21 and the reconstructed image captured and generated by the radiation detector 16 are matched. For example, highly X-ray absorbing markers are placed on the subject table 13 at five locations, at the four corners and the center of the imaging range, and the coordinates of the captured RGB-D image and the absorption image are matched. Therefore, the camera 21 functions as an imaging means for capturing an image from which the relative position (relative position information) of the subject relative to the grid in two or more dimensions can be obtained. The relative position information may be obtained using multiple cameras. For example, a means for obtaining a two-dimensional image of the subject H and a means for obtaining a three-dimensional image may be provided separately. Alternatively, the subject H may be held by a robot arm, and the relative position information may be obtained from the movement information of the robot arm. Alternatively, the relative position information may be obtained with high precision using a 3D scanner. Alternatively, if the subject H is a flat plate, the thickness information may be obtained by photographing it with a camera from the side (a combination of a normal camera from above and a normal camera from the side).

[0031] As shown in FIG. 3, the controller 5 includes a control unit 51, an operation unit 52, a display unit 53, a communication unit 54, and a storage unit 55. The control unit 51 is composed of a CPU (Central Processing Unit), RAM (Random Access Memory), etc. The control unit 51 is connected to each part of the main body 1 (for example, the radiation source 11, the radiation detector 16, the moving mechanism 15a, the camera 21, etc.) and controls the operation of each part. In addition, the control unit 51 executes various processes including an imaging process a described below in cooperation with a program stored in the storage unit 55. The control unit 51 also functions as a generating means for generating a reconstructed image based on a moiré fringe image obtained by irradiating radiation from the radiation source 11 to the subject H placed at a position overlapping with the radiation irradiation axis direction and capturing the image in cooperation with the radiation source 11, the gratings (multi-slit 12, first grating 14, second grating 15), the radiation detector 16, etc. The control unit 51 also functions as an acquiring means for acquiring relative position information, which is the relative position of the subject H with respect to the grating in two or more dimensions. The control unit 51 also functions as a control means for linking the relative position information with a reconstructed image, which will be described later.

[0032] The operation unit 52 includes a group of keys used for inputting the exposure switch and the imaging conditions, as well as a touch panel that is integrated with the display of the display unit 53, and outputs operation signals corresponding to these operations. and outputs it to the control unit 51. The display unit 53 displays an operation screen, the operating status of the main body unit 1, etc. on the display in accordance with the display control of the control unit 51.

[0033] The communication unit 54 includes a communication interface and communicates with external devices on the network.

[0034] The storage unit 55 is configured with a non-volatile semiconductor memory, a hard disk, etc., and stores programs executed by the control unit 51, data required for executing the programs, a shooting history, etc. The photographing history is linked to the photographing conditions, subject material information / molding conditions, the parent-child relationship of the subject (some of the child samples relative to the parent sample), environmental information such as temperature / vibration / air pressure at the time of photographing, various test data (in-situ, ash content measurement results, etc.), etc. The photographing history and the linked information may be recorded in an image header or the like, and then recorded in the memory unit 55. The memory unit 55 may be provided with a database (DB) separate from the controller 5, and the photographing history and the linked information may be managed in the DB.

[0035] (Photographed using a Talbot interferometer and a Talbot-Lau interferometer) Here, the imaging method using the Talbot interferometer and the Talbot-Lau interferometer will be explained. As shown in Figure 4, when X-rays emitted from the radiation source 11 pass through the first grating 14, the transmitted X-rays form images at regular intervals in the z direction. These images are called self-images, and the phenomenon of forming self-images is called the Talbot effect. The second grating 15 is positioned roughly parallel to the self-image at the position where the self-images are formed. A Moiré fringe image (indicated by Mo in Figure 4) is obtained from the X-rays that pass through the second grating 15. That is, the first grating 14 forms a periodic pattern, and the second grating 15 converts this periodic pattern into Moiré fringes. If an object H is present between the radiation source 11 and the first grating 14, the phase of the X-rays is shifted by the object H, causing the Moiré fringes on the Moiré fringe image to become distorted at the edge of the object H, as shown in Figure 4. This Moiré fringe distortion can be detected by processing the Moiré fringe image, allowing the object image to be visualized. This is the principle of the Talbot interferometer.

[0036] In the main body 1, a multi-slit 12 is placed between the radiation source 11 and the first grating 14 and close to the radiation source 11, and X-ray imaging is performed using a Talbot-Lau interferometer. The Talbot interferometer is based on the premise that the radiation source 11 is an ideal point radiation source, but in actual imaging, a focal spot with a relatively large focal diameter is used, and therefore the multi-slit 12 produces an effect as if X-rays were being irradiated from a series of multiple point radiation sources. This is the X-ray imaging method using a Talbot-Lau interferometer, and even when the focal spot diameter is relatively large, a Talbot effect similar to that of a Talbot interferometer can be obtained.

[0037] In the main body 1 of this embodiment, Moiré fringe images necessary to generate a reconstructed image of the subject H are captured by a fringe scanning method. Fringe scanning generally refers to relatively moving one (in this embodiment, the second grating 15) or two of the gratings (the multi-slit 12, the first grating 14, and the second grating 15) in the slit period direction (x direction) M times (M is a positive integer, M>2 for absorption images, and M>3 for differential phase images and small-angle scattering images) to capture M Moiré fringe images necessary to generate a reconstructed image. Specifically, if the slit period of the moving grating is d (μm), the grating is moved in the slit period direction by d / M (μm) steps, and capturing images is repeated to capture M Moiré fringe images.

[0038] Reconstructed images generated based on the Moiré fringe images include small-angle scattering images, differential phase images, and absorption images. Small-angle scattering images are images of X-ray scattering in microstructures, and the greater the X-ray scattering, the greater the signal value. Small-angle scattering images can capture aggregates of microstructures ranging from a few microns to tens of microns, which is smaller than the pixel size. Differential phase imaging visualizes the refraction of X-rays by the subject, with the greater the refraction of the X-rays, the greater the signal value. While absorption imaging has lower sensitivity for lighter elements, differential phase imaging maintains high sensitivity even for light elements, making it possible to detect changes in materials that are difficult to capture with absorption imaging. An absorption image is an image of the absorption of X-rays by the subject, and is equivalent to a conventional plain X-ray image.

[0039] To generate a reconstructed image, for example, first, offset correction, gain correction, defective pixel correction, X-ray intensity variation correction, etc. are applied to the subject moiré fringe image (moiré fringe image with the subject present). Next, a reconstructed image is generated based on the corrected subject moiré fringe image and a BG (Background) moiré fringe image used to generate the constituent images. The BG moiré fringe image is a moiré fringe image acquired by moving second grating 15 under the same X-ray irradiation conditions (tube voltage, mAs value, filter) as those for the subject moiré fringe image, with subject H removed from subject table 13. The absorption image is generated by logarithmically transforming a transmittance image generated by dividing an added image of M subject moiré fringe images by an added image of M BG moiré fringe images. The differential phase images are generated by calculating the phase of the moiré fringes for each of the subject moiré fringe image and the BG moiré fringe image using the principles of fringe scanning to generate a differential phase image with and without the subject, and then subtracting the differential phase image without the subject from the generated differential phase image with the subject. The small-angle scattering image is generated by calculating the visibility of the moiré fringes (visibility = amplitude ÷ average value) for each of the subject moiré fringe image and the BG moiré fringe image using the principles of fringe scanning to generate a small-angle scattering image with an object and a small-angle scattering image without an object, and then dividing the generated small-angle scattering image with an object by the small-angle scattering image without an object.

[0040] (Operation of X-ray Talbot Imaging Device 100 Example 1) Next, the operation of the X-ray Talbot imaging device 100 will be described. 5 is a flowchart showing imaging process a executed by cooperation between the control unit 51 of the X-ray Talbot imaging device 100 and a program stored in the storage unit 55. In imaging process a, the subject H is moved to four positions as shown in FIG. 6, images are taken at imaging positions A to D, and the reconstructed images (small-angle scattering image, differential phase image, absorption image) generated for each imaging position A to D are combined to generate an image capturing an area larger than the imaging area captured in a single imaging operation.

[0041] When the imaging process a is started, the control unit 51 acquires M BG moiré fringe images (Ref images) without the subject H placed on the subject table 13 by moving the second grating 15 under the same X-ray irradiation conditions (tube voltage, mAs value, filter) as those for the subject moiré fringe image (step S11). In the first embodiment, it is assumed that four images are acquired. After acquiring the BG moiré fringe image (Ref image), the user places the subject H on the subject stage 13.

[0042] Next, the control unit 51 causes the camera 21 to capture an image of the subject H and acquire an RGB-D image (step S12).

[0043] Next, the control unit 51 acquires relative position information, which is the relative position of the subject H with respect to the grid in two or more dimensions, from the RGB-D image (step S13).

[0044] Next, the control unit 51 controls the radiation source 11, the moving mechanism 15a, the radiation detector 16, etc. to perform imaging (referred to as Talbot imaging) to obtain moiré fringe images (Spl images) using the Talbot effect (step S14). In this embodiment, M (four) moiré fringe images (Spl images) of the subject are obtained by moving the grating (second grating 15 in this embodiment) in the slit periodic direction using a fringe scanning method.

[0045] Next, the control unit 51 determines whether the position of the subject H has changed (step S15). In the first embodiment, since image capture is performed at four locations, namely, image capture positions A to D shown in FIG. 6, steps S11 to S14 are repeated four times. Therefore, after repeating the image capture position change four times, the control unit 51 determines that the position of the subject H has not changed (step S15: NO) and proceeds to step S16. If the control unit 51 determines that the position of the subject H has changed (step S15: YES), the user moves the subject H from the subject table 13 and then proceeds to step S11. Note that if the control unit 51 determines that the position of the subject H has changed (step S15: YES), the user may proceed to step S12 without acquiring a BG moiré fringe image again. Note that the subject H may be moved from the subject table 13 manually, but it is preferable to use an electric stage or the like in terms of movement accuracy.

[0046] Next, reconstructed images (small-angle scattering image, differential phase image, absorption image) are generated based on the BG fringe moiré image at each photographing position and the subject moiré fringe image (step S16). In Example 1, four images are generated. The reconstructed images are associated with relative position information at each photographing position, an image number for identifying the image, inspection conditions, photographing conditions in Talbot photography, photographing date and time, etc., and are stored in storage unit 55.

[0047] Next, the control unit 51 derives a position correction amount based on the relative position information at each imaging position (step S17). The derivation of the position correction amount will be described later. For example, a gradient descent method may be used. Note that when the subject is thick, the influence of oblique X-ray incidence cannot be ignored, and this influence must be taken into consideration.

[0048] Finally, the control unit 51 corrects the positional shift of the reconstructed image at each position based on the position correction amount derived in step S17, and combines the reconstructed images at each position (step S18). Note that if the position of the subject H is never moved, steps S17 and S18 may be completed without being executed. Furthermore, the positional shift correction may be performed on the subject moiré fringe image before creating the reconstructed image. This method provides higher accuracy.

[0049] Therefore, by using the relative position of the subject H with respect to the grid in two or more dimensions, it is possible to align the subject with high precision and generate an image capturing a larger range than the range of a single shot. In addition, since alignment can be performed without using markers, no missing parts occur.

[0050] Example 2 In Example 2, as shown in Figure 7, subject H is moved to three shooting positions (relative angles to the lattice are 0°, 60°, and 120°) and photographed, and the reconstructed images (small-angle scattering images) generated for each shooting position are combined to generate a small-angle scattering orientation image. The processing flow is the same as in Example 1, and in step S18, the control unit 51 generates a small-angle scattering orientation image. The small-angle scattering orientation image is an image showing the orientation of materials such as fibers inside the subject H, obtained by analyzing multiple small-angle scattering images generated based on Moiré fringe images taken by setting the relative angle between the subject H and the lattice around the radiation irradiation axis to three or more angles.

[0051] 7 shows three shooting positions with relative angles to the grid of 0°, 60°, and 120°, but this is not limiting. The relative angle to the grid is determined by the number of times (N) of shooting, and is determined based on the following formula (1). Relative angle = 180° / N (*N is an integer of 3 or greater)... Equation (1)

[0052] Therefore, by using the relative position of the subject H with respect to the lattice in two or more dimensions, it is possible to align the position with high precision and generate a small-angle scattering orientation image. Furthermore, since correction can be performed without attaching markers, no missing parts occur. Furthermore, since it is possible to correct the positional deviation by knowing the rotation center of the subject, by returning the rotation around the pixel corresponding to the rotation center of the subject, it is possible to correct the positional deviation with higher precision than by returning the rotation at the center of the image. When correcting positional deviation from an image, it is not known which pixel the actual rotation center corresponds to, so it is necessary to rotate back using the rotation center (usually the center of the image) as designed for the subject table 13 of the X-ray Talbot imaging device 100 as the rotation center, which can be a source of error.

[0053] Example 3 In Example 3, as shown in Fig. 8, subject H is moved to two imaging positions (at relative angles of 0° and 90° with respect to the grating) and images are taken, and the reconstructed images (small-angle scattering image, differential phase image, absorption image) generated for each imaging position are combined to generate reconstructed images (small-angle scattering image, differential phase image, absorption image). The processing flow is the same as in Example 1, and in step S18, control unit 51 generates the combined reconstructed images (small-angle scattering image, differential phase image, absorption image).

[0054] 8, in the image combination in step S18, specifically, the value of each pixel is calculated using the average of each pixel or the square root of the sum of squares of each pixel as shown in the following formula: In particular, for small-angle scattering images and differential phase images, the influence of the orientation of the subject H relative to the grid can be reduced.

number

[0055] Therefore, by using the relative position of the subject H with respect to the grid in two or more dimensions, it is possible to align the subject with high precision and generate small-angle scattering images, differential phase images, and absorption images. Furthermore, since correction can be performed without attaching markers, no missing parts occur. Furthermore, since it is possible to correct the positional deviation by knowing the center of rotation of the subject, it is possible to align the subject by returning the rotation based on the center of the image, which means that it is possible to correct the positional deviation with higher precision than correcting the positional deviation using images.

[0056] Example 4 In Example 4, as shown in FIG. 9 , reconstructed images (small-angle scattering image, differential phase image, absorption image) of six child samples of subject H (parent sample) are captured and combined based on positional information of the child samples relative to the parent sample (the relative position of subject H relative to the lattice in two or more dimensions) to generate reconstructed images of the parent sample (small-angle scattering image, differential phase image, absorption image). The processing flow is the same as in Example 1, and in step S18, the control unit 51 generates reconstructed images of the parent sample (small-angle scattering image, differential phase image, absorption image). Furthermore, before capturing images, it is necessary to cut out the child samples from the parent sample and manage the parent-child relationships and cut-out positions of the samples in a DB.

[0057] Therefore, the state of the parent sample can be accurately restored from images of multiple child samples.

[0058] Example 5 10 is a flowchart showing imaging feasibility determination process b executed by cooperation between the control unit 51 of the X-ray Talbot imaging device 100 and a program stored in the storage unit 55. The imaging feasibility determination process b is a process for determining whether imaging is possible based on material and composition information input using the operation unit 52, thickness information of the subject H obtained from the RGB-D image, past imaging information, and current imaging conditions.

[0059] First, the control unit 51 obtains information on the material and composition of the subject H via the operation unit 52 (step S21).

[0060] Next, the control unit 51 causes the camera 21 to capture an image of the subject H and acquire an RGB-D image (step S22).

[0061] Next, the control unit 51 acquires relative position information (particularly, thickness information) that is the relative position of the subject H with respect to the grid in two or more dimensions from the RGB-D image (step S23).

[0062] Next, the control unit 51 refers to the photographing conditions of similar subjects photographed in the past stored in the storage unit 55 based on the material, composition information, and thickness information, compares them with the current photographing conditions, and determines whether or not photographing is possible (step S24). Note that photographing possible conditions may also be derived. Specifically, the subject H may be a thick aluminum plate. In this case, if the X-rays irradiated from the radiation source 11 are weak, they will not penetrate the subject H and imaging will not be possible. Therefore, in step S24, the control unit 51 determines that imaging is not possible. The control unit 51 also derives the setting (mAs value) of the radiation source 11 according to the thickness. In the above, whether or not imaging is possible is determined by referring to past imaging information, but this is not limiting. For example, whether or not imaging is possible may be determined by calculating the amount of transmitted X-rays based on physical property information of the subject H.

[0063] Next, the control unit 51 notifies the user whether or not photography is possible via the display unit 53 (step S25). Finally, the control unit 51 notifies the user of the photography possible conditions via the display unit 53 (step S26). The notification method is not limited to a screen display, and may be sound, audio, or LED display. Furthermore, if it is determined that shooting is not possible, the configuration may be such that shooting does not begin. Furthermore, if a command to start shooting is given and shooting will not produce a good-quality image, the configuration may be such that shooting will not be possible, and the device may still be able to shoot. Furthermore, if shooting is possible, the processing may end without issuing a notification of whether shooting is possible (step S25) or a notification of shooting possible conditions (step S26).

[0064] Therefore, the user can accurately grasp the conditions under which an image with the required image quality (contrast, etc.) can be captured, and the effort required to determine whether or not a capture is possible can be reduced.

[0065] (Derivation of position correction amount) The derivation of the position correction amount executed by the control unit 51 in step S17 of FIG. 5 will be described based on photographing the subject H at two photographing positions (relative angles to the grid are 0° and 90°) (Example 3). As shown in the upper part of FIG. 11, the imaging positions are two positions rotated by 90° around the radiation irradiation axis. The second row from the top of Figure 11 shows relative position information of subject H when considered in three dimensions at two imaging positions. The circles on subject H are markers. Checking the left and right diagrams reveals that subject H is rotated 90 degrees around the radiation irradiation axis. Note that the markers are provided to make the explanations and diagrams easier to understand, and are not necessary for the present invention. The third row from the top in Fig. 11 shows the reconstructed images (reconstructed image A0, reconstructed image B0) at the two shooting positions and the relative position information of subject H. Because the reconstructed images are two-dimensional, they are compressed in the z direction, and the three-dimensional relative position information is converted to two dimensions. The fourth row from the top in FIG. 11 shows the relative position information between the subject H and a reconstructed image B1 obtained by rotating a reconstructed image of the subject H at an imaging position rotated 90 degrees around the radiation irradiation axis by minus 90 degrees.

[0066] The amount of position correction is derived by comparing the relative position information of the same location of the subject H in the reconstructed image A0 and the reconstructed image B1. The amount of position correction is derived in the parallel direction (Xcor, Ycor) and the rotational direction (ΘCor). For example, using the following equation (2), Xcor, Ycor, and Θcor that minimize diff are derived by gradient descent, and positional deviation correction (translation and rotation) is applied to the reconstructed image A0 or the reconstructed image B1. diff=|x3-X1|+|x4-X2|+|y3-Y1|+|y4-Y2| ...Equation (2) Note that methods other than the gradient descent method may also be used.

[0067] [Second embodiment] In the second embodiment, as shown in Fig. 12, in addition to the first embodiment, an RGB-D camera is used to perform imaging even when imaging using another modality. The control unit 51 then acquires an image and relative position information (acquired from an RGB-D image in the other modality) from the other modality, and matches the other modality with the subject image of the X-ray Talbot imaging device 100 based on the relative position information. The other modality may be any modality that outputs image data that allows the imaging range and subject to be grasped in the same coordinate system, and examples thereof include SEM, μCT, and high-resolution Talbot. In other words, the control unit 51 functions as an acquisition means for acquiring relative position information, which is the relative position of the subject relative to the grid in two or more dimensions (relative position information acquired in another modality and relative position information in imaging using the X-ray Talbot imaging device 100).

[0068] 13 shows an example in which a reconstructed image A1 obtained by the X-ray Talbot imaging device 100 and an image A2 obtained by another modality (SEM) are displayed side by side on the display unit 53. Since the position coordinates of the reconstructed image A1 and the image A2 correspond to each other, it is possible to display an image A2 corresponding to a part of the reconstructed image A1.

[0069] 14 shows an example in which a reconstructed image A3 obtained by the X-ray Talbot imaging device 100 and images A4 and A5 obtained by another modality (SEM) are displayed side by side on the display unit 53. Since the position coordinates of the reconstructed image A3, images A4, and A5 correspond to each other, it is possible to display images A4 and A5 corresponding to a part of the reconstructed image A3.

[0070] Therefore, by using the relative position of the subject H with respect to the grid in two or more dimensions, accurate registration is possible, enabling position matching of images between two or more different modalities. In addition, because registration can be performed without using markers, no missing parts occur.

[0071] [Third embodiment] In the third embodiment, as shown in FIG. 15, in addition to the first embodiment, CAD is used, and the control unit 51 matches the coordinates of the reconstructed images (small-angle scattering image, differential phase image, absorption image) obtained by the X-ray Talbot imaging device 100 with the coordinates of the images created by CAD, based on the relative position of the subject H in two or more dimensions with respect to the grid obtained from the RGB-D image, and generates data in a format that can be fed back to CAE (computer-aided engineering). In other words, the control unit 51 functions as an acquisition means for acquiring relative position information (coordinate information of an image created by CAD and relative position information obtained from an RGB-D image) which is the relative position of the subject relative to the grid in two or more dimensions.

[0072] 15, a fluid analysis result of three-dimensional information is obtained from a 3D model of the subject created by CAD, and the information in the Z direction is compressed (integrated taking into account vectors) to obtain a fluid analysis result A6 of a two-dimensional image. The position of the fluid analysis result A6 of the two-dimensional image is matched to the position of a reconstructed image A7 obtained by the X-ray Talbot imaging device 100.

[0073] Therefore, by using the relative position of the subject H with respect to the grid in two or more dimensions, it is possible to align the subject with high precision, and it is possible to accurately match the position with the image obtained from CAD. In addition, since alignment can be performed without using markers, no missing parts occur. This is particularly useful because it allows accurate comparison of fluid analysis results with orientation images.

[0074] [Other embodiments] It is also possible to overlay the reconstructed image and the RGB-D image, allowing you to compare and check them.

[0075] Furthermore, even higher accuracy in positioning is possible by using the photographing history and associated information stored in the memory unit 55. In particular, this is possible by understanding the state of the subject H based on environmental information such as temperature, vibration, and atmospheric pressure at the time of photographing, and on the relationship with various test data (in-situ, ash content measurement results, etc.).

[0076] As described above, the radiographic imaging device has a radiation source, multiple gratings, and a radiation detector arranged in the direction of the radiation irradiation axis, and is equipped with a generation means (control unit 51) that generates a reconstructed image based on a moiré fringe image obtained by irradiating a subject positioned at a position overlapping the direction of the radiation irradiation axis with radiation from the radiation source and photographing the subject, an acquisition means (control unit 51) that acquires relative position information that is the relative position of the subject with respect to the grating in two or more dimensions, and a control means (control unit 51) that links the relative position information to the reconstructed image.This makes it possible to align images taken multiple times with high precision and without positional deviation, even for subjects that do not have significant features on the images and are larger than the range of a single photograph. The acquisition means (control unit 51) may acquire captured images and relative position information acquired by a modality other than the radiation imaging device.

[0077] The acquisition means may acquire the relative position information from an image captured by an image capture means that captures an image from which relative position information can be acquired.

[0078] In addition, the generating means generates a plurality of reconstructed images, and uses the relative position information to correct the positions of the plurality of reconstructed images to generate a combined image. Therefore, even if there are no significant features on the image and the subject is larger than the range of a single shot, the images taken multiple times can be aligned with high precision without any positional deviation, making it possible to combine the images with high precision.

[0079] In addition, the generation means uses relative position information of the subject cut out from the parent sample to combine reconstructed images of the subject cut out from the same parent sample to generate a reconstructed image of the parent sample.Therefore, even for subjects that do not have significant features on the image and are larger than the range of a single shot, images taken multiple times can be aligned with high precision without any positional deviation, making it possible to combine the images with high precision.

[0080] In addition, the generation means generates multiple reconstructed images, which are small-angle scattering images, and the generation means generates an orientation image using small-angle scattering images at three or more angles rotated around the radiation irradiation axis and whose positions have been corrected using relative position information.Therefore, even if there are no major features on the image and the subject is larger than the range of a single shooting, images taken multiple times can be aligned with high precision without any positional deviation, making it possible to obtain a highly accurate orientation image.

[0081] Furthermore, the generating means generates a plurality of reconstructed images, which are small-angle scattering images or differential phase images, and the generating means generates an image by combining small-angle scattering images or differential phase images at two or more angles that have been rotated around the radiation irradiation axis and whose positions have been corrected using relative position information.Therefore, even if there are no major features on the image and the subject is larger than the range of a single shooting, images taken multiple times can be aligned with high precision without any positional deviation, making it possible to combine the images with high precision.

[0082] In addition, the generation means associates the coordinate information of the CAD (computer-aided design) model with the relative position information and generates data in a format that can be fed back to CAE (computer-aided engineering), making it possible to align the CAD image and the reconstructed image with high precision and without any positional deviation.

[0083] Furthermore, the control means determines whether or not photography is possible based on information about the material and / or composition of the subject and information about the subject's thickness obtained from the relative position information, thereby reducing the user's effort in determining whether or not photography is possible.

[0084] In addition, the control means derives the photographing conditions from the material and / or composition information of the subject and the thickness information of the subject obtained from the relative position information, so that the user can set appropriate photographing conditions by deriving the photographing conditions.

[0085] Furthermore, the image generation method uses a generation means to generate a reconstructed image based on a moiré fringe image obtained by irradiating a subject positioned in a direction overlapping with the radiation irradiation axis with radiation from the radiation source and capturing the image, in which a radiation source, a plurality of gratings, and a radiation detector are arranged side by side in the direction of the radiation irradiation axis, and the acquisition means acquires relative position information, which is the relative position of the subject with respect to the grating in two or more dimensions, and the control means links the relative position information to the reconstructed image. Therefore, even for a subject that does not have any significant features on the image and is larger than the range of a single capture, it is possible to align and combine images captured multiple times with high precision and without any positional deviation, and generate a reconstructed image.

[0086] In addition, the radiography system is a radiography system that includes the above-mentioned radiography device and a device that includes at least one of μCT, SEM, and high-resolution Talbot, and the analysis results of the device and the reconstructed image are position-matched using relative position information, making it possible to align the analysis results of another device and the reconstructed image obtained from the radiography device with high precision without any positional deviation.

[0087] Furthermore, the radiation imaging system includes the radiation imaging device and uses relative position information to display the reconstructed image and the optical image obtained by the imaging means in an overlapping manner, thereby enabling the overlapping to occur without any positional deviation.

[0088] The program also causes the computer of a radiographic imaging device, in which a radiation source, multiple gratings, and a radiation detector are arranged in the radiation irradiation axis direction, to function as a generation means for generating a reconstructed image based on a moiré fringe image obtained by irradiating a subject positioned in a position overlapping the radiation irradiation axis direction with radiation from the radiation source and photographing the subject; an acquisition means for acquiring relative position information, which is the relative position of the subject in two or more dimensions with respect to the grating; and a control means for linking the relative position information with the reconstructed image.This makes it possible to align images taken multiple times with high precision and without positional deviation, even for subjects that do not have significant features on the images and are larger than the range of a single photograph.

[0089] The first and second embodiments of the present invention and their modifications have been described above, but the description of the above-described embodiments is a preferred example of the present invention, and the present invention is not limited to this.

[0090] For example, in the above embodiment, an inspection device using a Talbot-Lau interferometer in which the second grating 15 is moved relative to the multi-slit 12 and the first grating 14 during imaging using the fringe scanning method has been described as an example. However, the present invention may also be applied to an inspection device using a Talbot-Lau interferometer in which either the multi-slit 12, the first grating 14, or the second grating 15, or two of these gratings, are moved during imaging using the fringe scanning method. The present invention may also be applied to an inspection device using a Talbot interferometer in which either the first grating 14 or the second grating 15 is moved relative to the other grating. The present invention may also be applied to an inspection device using a Law interferometer in which either the multi-slit 12 or the first grating 14 is moved relative to the other grating. The present invention may also be applied to a Talbot-Lau interferometer, Talbot interferometer, or Law interferometer that uses a Fourier transform method that does not require fringe scanning.

[0091] Furthermore, in the above embodiment, an example has been described in which a small-angle scattering image, a differential phase image, and an absorption image are generated based on a moiré fringe image obtained by Talbot photography, but the present invention can be realized as long as a small-angle scattering image and / or a differential phase image is generated.

[0092] Furthermore, for example, in the above description, examples have been disclosed in which a hard disk or a semiconductor nonvolatile memory is used as a computer-readable medium for the program according to the present invention, but the present invention is not limited to this example. Portable recording media such as CD-ROMs can also be used as other computer-readable media. Furthermore, carrier waves can also be used as a medium for providing data for the program according to the present invention via a communication line.

[0093] In addition, the detailed configuration and detailed operation of each device constituting the X-ray Talbot imaging device can be modified as appropriate without departing from the spirit of the invention. [Explanation of symbols]

[0094] 100 X-ray Talbot Imaging Device 1 Main body 11 Radiation source 12 Multi-slit 13 Subject stand 14 1st grid 15 2nd grid 15a Moving mechanism 16 Radiation detector 17 Posts 17a Cushioning material 111 focus 112 Additional filter / collimator 120 First cover unit 130 Second cover unit 19 Base 21 Camera 5 Controllers 51 Control section 52 Operation section 53 Display section 54 Communications Department 55 Storage section

Claims

1. a generating means for generating a reconstructed image based on a moiré fringe image obtained by irradiating a subject, which is disposed at a position overlapping with the radiation irradiation axis direction, with radiation from the radiation source and photographing the subject; and an acquisition means for acquiring relative position information that is a relative position of the subject with respect to the grid in two or more dimensions; a control means for linking the relative position information with the reconstructed image; Equipped with The control means determines whether or not imaging is possible based on information about the material and / or composition of the subject and information about the thickness of the subject obtained from the relative position information.

2. a generating means for generating a reconstructed image based on a moiré fringe image obtained by irradiating a subject, which is disposed at a position overlapping with the radiation irradiation axis direction, with radiation from the radiation source and photographing the subject; and an acquisition means for acquiring relative position information that is a relative position of the subject with respect to the grid in two or more dimensions; a control means for linking the relative position information with the reconstructed image; Equipped with The control means derives imaging conditions from material and / or composition information of the subject and thickness information of the subject obtained from the relative position information.

3. 3. The radiographic imaging apparatus according to claim 1, wherein the acquisition unit acquires the relative position information from an image captured by an imaging unit that captures an image from which the relative position information can be acquired.

4. the generating means generates a plurality of reconstructed images; 4. The radiographic imaging apparatus according to claim 1, wherein the generating unit generates a combined image by correcting the positions of the plurality of reconstructed images using the relative position information.

5. The radiographic imaging device according to any one of claims 1 to 4, characterized in that the generating means uses the relative position information of the subject cut out from the parent sample to combine the reconstructed images of the subject cut out from the same parent sample, thereby generating the reconstructed image of the parent sample.

6. the generating means generates a plurality of reconstructed images; the reconstructed image is a small-angle scattering image; 4. The radiographic imaging device according to claim 1, wherein the generating means generates an orientation image using the small-angle scattering image rotated at three or more angles around the radiation irradiation axis after position correction using the relative position information.

7. the generating means generates a plurality of reconstructed images; the reconstructed image is a small-angle scattering image or a differential phase image; 4. The radiographic imaging apparatus according to claim 1, wherein the generating means generates an image by combining the small-angle scattering images or the differential phase images at two or more angles rotated around the radiation irradiation axis after position correction using the relative position information.

8. 8. The radiographic apparatus according to claim 1, wherein the generating means associates coordinate information of a CAD (computer-aided design) model with the relative position information and generates data in a format that can be fed back to CAE (computer-aided engineering).

9. a generating means for generating a reconstructed image based on a Moiré fringe image obtained by irradiating a subject placed at a position overlapping with the radiation irradiation axis direction with radiation from the radiation source and capturing the image, the generating means including a radiation source, a plurality of gratings, and a radiation detector arranged in a line in the radiation irradiation axis direction; acquiring relative position information, which is a two-dimensional or more dimensional relative position of the subject with respect to the grid, by an acquisition means; linking the relative position information with the reconstructed image by a control means; The control means determines whether or not photography is possible based on information about the material and / or composition of the subject and information about the thickness of the subject obtained from the relative position information.

10. a generating means for generating a reconstructed image based on a Moiré fringe image obtained by irradiating a subject placed at a position overlapping with the radiation irradiation axis direction with radiation from the radiation source and capturing the image, the generating means including a radiation source, a plurality of gratings, and a radiation detector arranged in a line in the radiation irradiation axis direction; acquiring relative position information, which is a two-dimensional or more dimensional relative position of the subject with respect to the grid, by an acquisition means; linking the relative position information with the reconstructed image by a control means; The control means derives photographing conditions from material and / or composition information of the subject and thickness information of the subject obtained from the relative position information.

11. The radiographic imaging apparatus according to any one of claims 1 to 8, a device for outputting image data that allows the photographing range and the subject to be grasped in the same coordinate system; A radiography system comprising: A radiation imaging system that performs positional matching between the analysis result of the device and the reconstructed image using the relative position information.

12. A radiation imaging system comprising the radiation imaging apparatus according to claim 3, A radiation imaging system that uses the relative position information to align and superimpose the reconstructed image and the optical image obtained by the imaging means and displays them.

13. A computer of a radiographic apparatus in which a radiation source, a plurality of gratings, and a radiation detector are arranged in a direction of a radiation irradiation axis, a generating means for generating a reconstructed image based on a moiré fringe image obtained by irradiating radiation from the radiation source onto a subject disposed at a position overlapping with the radiation irradiation axis direction and performing imaging; an acquisition means for acquiring relative position information that is a relative position of the subject with respect to the grid in two or more dimensions; functioning as a control means for linking the relative position information with the reconstructed image; The control means is a program for determining whether or not photography is possible based on information on the material and / or composition of the subject and information on the thickness of the subject obtained from the relative position information.

14. A computer of a radiographic apparatus in which a radiation source, a plurality of gratings, and a radiation detector are arranged in a direction of a radiation irradiation axis, a generating means for generating a reconstructed image based on a moiré fringe image obtained by irradiating radiation from the radiation source onto a subject disposed at a position overlapping with the radiation irradiation axis direction and performing imaging; an acquisition means for acquiring relative position information that is a relative position of the subject with respect to the grid in two or more dimensions; functioning as a control means for linking the relative position information with the reconstructed image; The control means is a program for deriving photographing conditions from information on the material and / or composition of the subject and information on the thickness of the subject obtained from the relative position information.

Images