WO2024203397A1

WO2024203397A1 - X-ray talbot imaging condition calculation device, x-ray talbot imaging condition calculation method, x-ray talbot imaging system, x-ray talbot imaging condition display device, and program

Info

Publication number: WO2024203397A1
Application number: PCT/JP2024/010042
Authority: WO
Inventors: 智宏森; 昌宏今田; 愛彦江口
Original assignee: コニカミノルタ株式会社
Priority date: 2023-03-31
Filing date: 2024-03-14
Publication date: 2024-10-03

Abstract

An X-ray Talbot imaging condition calculation device 2 calculates an imaging condition in a Talbot imaging means (X-ray imaging system 100), which generates a small-angle scattering image and/or a differential phase image of a subject, the X-ray Talbot imaging condition calculation device comprising: a reception means (control unit 21) that receives an input of subject information; and a calculation means (control unit 21) that calculates an imaging condition on the basis of the subject information and past imaging information and/or a theoretical calculation formula.

Description

X-ray Talbot radiography condition calculation device, X-ray Talbot radiography condition calculation method, X-ray Talbot radiography system, X-ray Talbot radiography condition display device and program

The present invention relates to an X-ray Talbot imaging condition calculation device, an X-ray Talbot imaging condition calculation method, an X-ray Talbot imaging system, an X-ray Talbot imaging condition display device, and a program.

Conventionally, X-ray Talbot imaging devices using a Talbot interferometer or a Talbot-Lau interferometer that utilizes the Talbot effect have been known. It is not easy to judge whether or not imaging is possible using the X-ray Talbot imaging device and to determine appropriate imaging conditions. This is because, in Talbot imaging, the X-ray transmittance and scattering strength change depending on the material and thickness of the subject.
For this reason, it is necessary to estimate the X-ray transmittance and scattering strength from the material and thickness of the subject to determine whether or not imaging is possible, or to consider in advance whether to change the imaging conditions.

Possible methods for advance consideration include Method A (Patent Document 1), which involves searching past imaging cases for cases similar to the subject to be imaged, and setting imaging conditions based on those conditions; and Method B (

Non-Patent Documents

1, 2, 3, 4, 5), which involves calculating the amount of X-ray transmission, refraction angle, amount of scattering, etc. from characteristic information such as the thickness and material of the subject, and setting imaging conditions by theoretically predicting image quality.

JP 2020-061284 A

The method A can present shooting conditions that are likely to obtain a desired image quality based on actual cases, but cannot present shooting conditions for an unknown subject for which there are no similar shooting cases.
In addition, in the above method B, by applying theoretical prediction, it is possible to predict image quality and present shooting conditions based on the image quality prediction even for unknown subjects. On the other hand, it is difficult to perform calculations by comprehensively inputting all the characteristics of real subjects. In other words, although there are theoretical calculation formulas for subjects with simple configurations, the characteristics of real subjects are complex, and there are no theoretical calculation formulas that can handle all patterns of configurations, so it is not necessarily appropriate to determine shooting conditions only by theoretical calculation formulas.
Also, if the subject to be photographed is actually at hand and the device is nearby, it is possible to adjust the parameters by actually placing the subject on the device and taking a test shot. However, this requires actual shooting, and it is necessary to secure time to use the device and then take multiple shots with parameter adjustments to check the shooting results, which is time-consuming and laborious. If the subject is not at hand or the device is not nearby, it is necessary to prepare a subject for testing, go to a location where the device is located, or send the subject to have it photographed, which takes even more time and labor.

The objective of the present invention is therefore to provide a means by which even inexperienced users can easily determine more appropriate shooting conditions for Talbot photography.

In order to solve the above problems, the X-ray Talbot radiography condition calculation device of the present invention comprises:
1. An X-ray Talbot imaging condition calculation device that calculates imaging conditions in a Talbot imaging means that captures a small-angle scattering image and/or a differential phase image of a subject, comprising:
A receiving means for receiving input of subject information;
A calculation means for calculating a photographing condition based on the subject information, past photographing information and/or a theoretical calculation formula;
Equipped with.

Further, the X-ray Talbot radiography condition calculation method of the present invention comprises the steps of:
1. An X-ray Talbot imaging condition calculation method using an X-ray Talbot imaging condition calculation device that calculates imaging conditions in a Talbot imaging means that captures a small angle scattering image and/or a differential phase image of a subject, comprising:
A receiving step of receiving input of subject information;
a calculation step of calculating a photographing condition based on the subject information, past photographing information and/or a theoretical calculation formula;
Includes.

Further, the X-ray Talbot imaging system of the present invention comprises:
a Talbot imaging means which comprises a radiation source, a plurality of gratings, and a radiation detector arranged in a direction of a radiation irradiation axis, and which captures at least a small-angle scattering image and/or a differential phase image of a subject based on a Moiré fringe image obtained by irradiating a subject arranged in the direction of the radiation irradiation axis with radiation from the radiation source and capturing the image;
A receiving means for receiving input of subject information;
A calculation means for calculating a photographing condition based on the subject information and past photographing information;
Equipped with.

In addition, the program of the present invention is
a computer of an X-ray Talbot imaging condition calculation device that calculates imaging conditions in a Talbot imaging means that captures a small angle scattering image and/or a differential phase image of a subject,
A receiving means for receiving input of subject information;
a calculation means for calculating a photographing condition based on the subject information, past photographing information and/or a theoretical calculation formula;
Function as.

The X-ray Talbot radiography condition display device of the present invention further comprises:
The X-ray Talbot imaging condition calculation device further includes a display unit for displaying the imaging conditions calculated by the calculation means of the X-ray Talbot imaging condition calculation device.

According to the present invention, even an inexperienced user can easily determine more appropriate shooting conditions for Talbot photography without taking test shots of the subject.

FIG. 1 is a schematic diagram illustrating an overall view of an X-ray Talbot imaging system. FIG. 1 is a diagram illustrating the principle of a Talbot interferometer. 3 is a schematic plan view of a source grating, a first grating, and a second grating. FIG. FIG. 2 is a block diagram showing a functional configuration of the image processing device. FIG. 13 is an image diagram of a shooting condition calculation process. 13 is a flowchart showing a shooting condition calculation process. FIG. 13 is an image diagram of an input screen. This is the relationship between X-ray energy and transmittance. FIG. 13 is an image diagram of an output screen. FIG. FIG. 13 is an image diagram of an input screen. FIG. 13 is an image diagram of a photography information database. This is the relationship between the thickness of the subject and the visibility rate. FIG. 13 is an image diagram of an output screen. FIG. FIG. 13 is an image diagram of an input screen. This is the relationship between X-ray energy and transmittance. This is the relationship between the mAs value and noise. This is the relationship between the mAs value and noise. This is the relationship between the mAs value and noise. 13 is an example of a calculation result of a differential phase image. 13 is an example of a calculation result of a differential phase image. FIG. 13 is an image diagram of an output screen. The relationship between orientation angle and frequency. The relationship between orientation angle and frequency. 1 is an example of a visual field arrangement. 1 is an example of a visual field arrangement. 1 is an example of a visual field arrangement. 1 is an example of a visual field arrangement. 1 is an example of a visual field arrangement. FIG. 13 is an image diagram of a feedback screen. This is the relationship between particle size and normalized signal value.

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

As shown in FIG. 1, an X-ray imaging system 100 according to this embodiment includes an X-ray Talbot imaging device 1 and an X-ray Talbot imaging condition calculation device 2.
The X-ray Talbot imaging device 1 employs a Talbot-Lau interferometer equipped with a source grating (also referred to as a G0 grating) 12. Note that it is also possible to employ an X-ray Talbot imaging device using a Talbot interferometer equipped only with a first grating (also referred to as a G1 grating) 14 and a second grating (also referred to as a G2 grating) 15 without the source grating 12.

[About the X-ray Talbot Imaging Device]
1 is a schematic diagram showing an overall image of an X-ray Talbot imaging device 1 according to this embodiment. As shown in FIG. 1, the X-ray Talbot imaging device 1 according to this embodiment includes an X-ray generator 11, a source grating 12, a subject table 13, a first grating 14, a second grating 15, an X-ray detector 16, a support 17, and a base unit 18.

According to the X-ray Talbot imaging device 1, at least three types of images can be reconstructed by capturing a moire image of the subject H at a predetermined position relative to the subject table 13 using a method based on the principle of the fringe scanning method, or by analyzing the moire image using the Fourier transform method (referred to as reconstructed images). In detail, the X-ray Talbot imaging condition calculation device 2 generates a reconstructed image based on the moire image read by the X-ray Talbot imaging device 1 and a moire image in a state where the subject H does not exist (referred to as a BG: Back Ground moire image). Note that the X-ray imaging system 100 captures a moire image in a state where the subject H does not exist at least once before or after the imaging of the subject H. However, imaging of another subject may be performed between the imaging of the subject H and the imaging of the BG moire image.
That is, there are three types of images: an absorption image (same as a normal X-ray absorption image) which visualizes the transmittance, which is the ratio between the average components of a BG moiré fringe image and a moiré fringe image; a differential phase image which visualizes the phase difference between a BG moiré fringe image and a moiré fringe image; and a small-angle scattering image which visualizes the visibility ratio, which is the ratio of the visibility (sharpness) of a BG moiré fringe image and a moiré fringe image.

The fringe scanning method is a method in which one of multiple gratings is moved in the direction of the slit period by 1/M (M is a positive integer, M>2 for absorption images, M>3 for differential phase images and small-angle scattering images) of the grating, and then reconstructed using the moiré images captured M times to obtain a high-resolution reconstructed image.

The Fourier transform method is a method in which, in the presence of a subject, a single moiré image is captured using an X-ray Talbot imaging device, and then in image processing, the moiré image is subjected to a Fourier transform or other process to reconstruct and generate an absorption image, differential phase image, and small-angle scattering image.

Next, the principle common to Talbot and Talbot-Lau interferometers will be explained using Figure 2.

Note that while Figure 2 shows the case of a Talbot interferometer, the case of a Talbot-Lau interferometer can be basically explained in the same way. Also, the z direction in Figure 2 corresponds to the vertical direction in the X-ray Talbot imaging device 1 in Figure 1, and the x and y directions in Figure 2 correspond to the horizontal directions (front-back and left-right directions) in the X-ray Talbot imaging device 1 in Figure 1.

As shown in FIG. 3 , the first grating 14 and the second grating 15 (and the source grating 12 in the case of a Talbot-Lau interferometer) have a plurality of slits S arranged at a predetermined period d in the x direction perpendicular to the z direction, which is the irradiation direction of the X-rays.
The periods of the source grating 12, the first grating 14, and the second grating 15 are not limited to being the same.

As shown in Figure 2, when X-rays irradiated from X-ray source 11a (X-ray generator 11) (in the case of a Talbot-Lau interferometer, the X-rays irradiated from X-ray source 11a are converted into multiple light sources by source grating 12 (not shown in Figure 2)) pass through first grating 14, the transmitted X-rays form images at regular intervals in the z direction. These images are called self-images (also called grating images, etc.), and the phenomenon in which self-images are formed at regular intervals in the z direction is called the Talbot effect.

In other words, the Talbot effect is a phenomenon in which, when coherent light passes through the first grating 14, which has slits S at a constant period d as shown in Figure 2, it forms self-images at constant intervals in the direction of light travel, as described above.

Then, as shown in FIG. 2, a second grating 15 having slits S with approximately the same period as the self-image of the first grating 14 is placed at the position where the self-image of the first grating 14 forms an image. At this time, if the extension direction of the slits S of the second grating 15 (i.e., the x-axis direction in FIG. 2) is placed approximately parallel to the extension direction of the slits S of the first grating 14, a moiré image Mo is obtained on the second grating 15.

In FIG. 2, the moire image Mo is drawn away from the second grating 15 because if the moire image Mo were drawn on the second grating 15, the moire fringes and slits S would be mixed together and would be difficult to understand. However, in reality, the moire image Mo is formed on the second grating 15 and downstream of it. This moire image Mo is then captured by the X-ray detector 16, which is placed directly below the second grating 15.

Also, as shown in FIG. 2, if the subject H is present between the X-ray source 11a (X-ray generator 11) and the first grating 14 (i.e., on the subject table 13 in FIG. 1), the subject H will cause the phase of the X-rays to shift or the X-rays to scatter. In the former case, the moire fringes of the moire image Mo will be disturbed at the boundary of the subject's edge, and in the latter case, the visibility rate of the scattered part will decrease, not limited to the subject's edge. On the other hand, although not shown, if the subject H is not present between the X-ray source 11a (X-ray generator 11) and the first grating 14, a moire fringe image that is not influenced by the subject H, that is, a BG moire image, will appear. This is the principle of the Talbot interferometer and the Talbot-Lau interferometer. The subject H may be placed behind the first grating 14.

Based on this principle, in the X-ray Talbot imaging device 1 according to this embodiment, for example as shown in FIG. 1, the second grating 15 is arranged in the second cover unit 130 at a position where the self-image of the first grating 14 forms an image. Also, as mentioned above, if the second grating 15 and the X-ray detector 16 are separated, the moire image Mo (see FIG. 2) becomes blurred, so in this embodiment, the X-ray detector 16 is arranged directly below the second grating 15.

The second cover unit 130 is provided to protect the X-ray detector 16, etc. by preventing people or objects from colliding with or touching the first grating 14, second grating 15, X-ray detector 16, etc.

Although not shown in the figure, the X-ray detector 16 is configured such that conversion elements that generate electrical signals in response to irradiated X-rays are arranged in a two-dimensional array (matrix), and the electrical signals generated by the conversion elements are read as image signals. In this embodiment, the X-ray detector 16 captures the moiré image Mo, which is an image of the X-rays formed on the second grating 15, as an image signal for each conversion element.

In this embodiment, the X-ray Talbot imaging device 1 captures multiple moiré images Mo using a so-called fringe scanning method. That is, in the X-ray Talbot imaging device 1 according to this embodiment, multiple moiré images Mo are captured while shifting the relative positions of the first grating 14 and the second grating 15 in the x-axis direction in Figures 1 to 3 (i.e., the direction perpendicular to the extension direction (y-axis direction) of the slit S). In another embodiment, the source grating 12 may be moved.

Then, the X-ray Talbot imaging condition calculation device 2 receives image signals of multiple moiré images Mo from the X-ray Talbot imaging device 1, and performs image processing to reconstruct an absorption image, a differential phase image, a small-angle scattering image, etc. based on the multiple moiré images Mo.

Therefore, in the X-ray Talbot imaging device 1 according to this embodiment, in order to capture multiple moire images Mo by the fringe scanning method, a moving device (not shown) is provided for moving the first grating 14 in the x-axis direction by a predetermined amount. Note that it is also possible to configure the device so that the second grating 15 is moved instead of the first grating 14, or so that both are moved. In another embodiment, the source grating 12 may be moved.

In addition, the X-ray Talbot imaging device 1 can be configured to capture only one moire image Mo while keeping the relative positions of the first grating 14 and the second grating 15 fixed, and then to reconstruct an absorption image, differential phase image, and small-angle scattering image by analyzing this moire image Mo using a Fourier transform method or the like in image processing in the image processing device.

When using this method, it is not necessary to provide the above-mentioned moving device etc. in the X-ray Talbot imaging device 1. Note that the present invention is also applicable to X-ray Talbot imaging devices that are not provided with such a moving device.

It is also possible to generate many more types of images by recombining the above three types of reconstructed images. For example, in orientation photography, small-angle scattering images taken at multiple (three or more) lattice facing angles are used, and after aligning each image, fitting is performed with a sine wave for each pixel to extract fitting parameters. A sine wave graph is a graph in which the horizontal axis represents the relative angle between the sample and the lattice, and the vertical axis represents the small-angle scattering signal value of a certain pixel. The amplitude, average, and phase of the sine wave are obtained as fitting parameters. An image showing the amplitude value for each pixel is called an orientation degree image, an image showing the average value for each pixel is called a scattering intensity image, and an image showing the phase for each pixel is called an orientation angle image. It is to be noted that the fitting method is not limited to a sine wave.
Hereinafter, the reconstructed image and the orientation images (orientation degree image, scattering intensity image, and orientation angle image) generated by recombining the reconstructed images will be referred to as a Talbot image.

The configuration of other parts of the X-ray Talbot imaging device 1 according to this embodiment will be described. This embodiment is a so-called vertical type, in which the X-ray generator 11, radiation source grating 12, subject table 13, first grating 14, second grating 15, and X-ray detector 16 are arranged in this order in the z direction, which is the direction of gravity. That is, in this embodiment, the z direction is the irradiation direction of X-rays from the X-ray generator 11.

The X-ray generator 11 is equipped with an X-ray source 11a, such as a Coolidge X-ray source or a rotating anode X-ray source that are widely used in medical settings. Other X-ray sources can also be used. The X-ray generator 11 of this embodiment is configured to irradiate X-rays in a cone beam shape from a focal point. In other words, the X-rays are irradiated so that they spread out the further away from the X-ray generator 11.

In this embodiment, the radiation source grating 12 is provided below the X-ray generator 11. In order to prevent vibrations of the X-ray generator 11 caused by the rotation of the anode of the X-ray source 11a, etc., from being transmitted to the radiation source grating 12, in this embodiment, the radiation source grating 12 is not attached to the X-ray generator 11, but is attached to a fixed member 18a attached to a base portion 18 provided on a support 17.

In this embodiment, a buffer member 17a is provided between the X-ray generator 11 and the support 17 to prevent vibrations from the X-ray generator 11 from propagating to other parts of the X-ray Talbot imaging device 1, such as the support 17 (or to reduce the amount of vibration that propagates).

In this embodiment, in addition to the radiation source grating 12, the fixed member 18a is equipped with a filtering filter (also called an additional filter) 112 for changing the radiation quality of the X-rays transmitted through the radiation source grating 12, an irradiation field aperture 113 for narrowing the irradiation field of the irradiated X-rays, and an irradiation field lamp 114 for irradiating the subject with visible light instead of X-rays for alignment before irradiating the subject with X-rays.

Note that the radiation source grating 12, the filtration filter 112, and the irradiation field aperture 113 do not necessarily have to be arranged in this order. In addition, in this embodiment, a first cover unit 120 is arranged around the radiation source grating 12 and other components to protect them.

The subject table 13 is a table on which the subject H is placed. The subject table 13 is provided with a fixing unit (not shown) that fixes the position of the subject H with respect to the X-rays irradiated from the X-ray generator 11. The fixing unit has a fixing part that can fix the subject H at a predetermined position, and a moving mechanism that can rotate the fixing part about the XY axis (two-dimensional direction) + Θ axis (any rotation angle in the XY plane). By using such a fixing unit and rotating the subject H in the XY plane, the same part of the subject H can be accurately photographed multiple times by the X-ray Talbot imaging device 1 with different shooting angles and lattice facing angles (lattice facing angles). Note that the subject H does not necessarily need to be fixed, and for example, if the subject H is a plate material or a dumbbell test piece that does not move on the subject table 13 even without being fixed, it can be photographed without being fixed.
Here, the imaging angle is an angle indicating the position of the subject H relative to the X-ray Talbot imaging device 1, and specifically, is a rotation angle from a reference position P of the subject table 13. Also, the grating facing angle is the relationship (angle) between the direction of the captured image (or the image displayed after imaging) and the direction of the gratings (the multi-slit 12, the first grating 14, and the second grating 15).

In addition, the degree of change in phase or the decrease in visibility rate varies depending on the relative angle between the lattice and the boundary between materials with different refractive indexes inside the subject, or the scatterer, and when generated as a reconstructed image, the image seen according to the angle varies. Therefore, by photographing the same part of the subject H multiple times with different lattice facing angles, it is possible to obtain multiple image sets of three types of reconstructed images (absorption image, differential phase image, small angle scattering image) based on the same moire image Mo for each angle. Here, in order to match the same part of the subject H in the images obtained for each lattice facing angle, alignment may be performed by image processing. In addition, the characteristics of the subject H may be used for alignment, or a marker for alignment other than the subject H may be photographed together with the subject H and the marker may be used.
In addition, in this embodiment, the imaging angle of the subject H is adjusted by the moving mechanism of the fixed unit, but a configuration may be adopted in which the X-ray source 11a, the

multiple gratings

12, 14, 15 (which may be grating holders), and the X-ray detector 16 rotate as a whole around the optical axis of the X-rays, thereby enabling imaging by changing the grating facing angle between the subject H and the gratings.

Although not shown in the figure, the X-ray Talbot imaging device 1 may be equipped with an optical photograph acquisition device that photographs a subject placed on a subject table from at least one of the x, y and z directions to acquire an optical photograph of the subject.

[About the X-ray Talbot radiography condition calculation device]
The X-ray Talbot imaging condition calculation device 2 can generate a Talbot image of the subject H and perform image processing of the Talbot image by using the moire image Mo obtained by the X-ray Talbot imaging device 1. Furthermore, the X-ray Talbot imaging condition calculation device 2 can calculate imaging conditions based on subject information, past imaging information and/or theoretical calculation formulas.
As shown in FIG. 4, the X-ray Talbot radiography condition calculation device 2 includes a control unit 21, an operation unit 22, a display unit 23, a communication unit 24, and a storage unit 25.
Moreover, the X-ray Talbot imaging condition calculation device 2 executes imaging condition calculation processing and imaging condition display processing, which will be described later.
The X-ray Talbot radiography condition calculation device 2 including the display unit 23 also functions as an image display device (X-ray Talbot radiography condition display device).

The control unit 21 is composed of a CPU (Central Processing Unit), a RAM (Random Access Memory), etc., and executes various processes including image processing, which will be described later, in cooperation with programs stored in the storage unit 25 .
The control unit 21 functions as a receiving unit that receives input of subject information.
The control unit 21 also functions as a calculation unit that calculates the shooting conditions based on the subject information, past shooting information and/or theoretical calculation formulas.
The control unit 21 also functions as a calculation means for calculating a predetermined feature amount based on past photographing information and/or a theoretical calculation formula. The feature amount refers to transmittance, scattering amount (visibility rate), etc. The visibility of the moire image Mo has the property of being reduced by scattering of the subject, and the greater the scattering amount, the smaller the visibility rate. Therefore, the visibility rate and the small-angle scattering image can be considered as visualization of the amount of X-ray scattering at each position of the subject.
The control unit 21 also functions as a selection unit that selects the imaging conditions based on the calculated feature amounts.
The control unit 21 also functions as a prediction unit that predicts the image quality of an image when photographed based on the photographing conditions.
The control unit 21 also functions as a determination unit that determines whether the predicted image quality satisfies a predetermined image quality condition.
The control unit 21 also functions as an extraction unit that searches the storage unit for past shooting information that matches or is similar to the subject information, and extracts shooting conditions in the matching or similar past shooting information.
The control unit 21 also functions as a display control unit that displays the shooting conditions on the display unit.
In addition, when the determination means determines that shooting conditions that satisfy the specified image quality conditions cannot be obtained, the control unit 21 functions as a second calculation means that calculates subject conditions in the subject information that satisfy the specified image quality conditions.
The control unit 21 also functions as a calculation means for calculating the degree of discrepancy between the image quality predicted when an image is captured based on the shooting conditions and the image quality of an image captured based on the shooting conditions.
The control unit 21 also functions as a feedback unit that performs feedback to the theoretical calculation formula based on the degree of deviation.
The control unit 21 also functions as a visualization unit that visualizes low-quality areas of a captured image.
The control unit 21 also functions as a means for calculating and presenting an appropriate arrangement of the photographing fields of view during tiling photographing.

The operation unit 22 is configured with a keyboard equipped with cursor keys, numeric input keys, various function keys, etc., and a pointing device such as a mouse, and outputs press signals of keys pressed on the keyboard and operation signals from the mouse as input signals to the control unit 21. It may also be configured with a touch panel integrated with the display of the display unit 23, and generate operation signals corresponding to these operations and output them to the control unit 21.

The display unit 23 is configured with a display such as a CRT (Cathode Ray Tube) or LCD (Liquid Crystal Display), and displays various display screens, etc., according to the display control of the control unit 21.

The communication unit 24 has a communication interface and communicates with the X-ray Talbot imaging device 1 on the communication network and with external systems such as a PACS (Picture Archiving and Communication System) via wired or wireless communication.

The storage unit 25 is configured with a non-volatile semiconductor memory, a hard disk, or the like, and stores the programs executed by the control unit 21, data necessary for executing the programs, and the like.
The storage unit 25 functions as a storage unit that stores the past shooting information in association with the subject information of the subject photographed using the past shooting information. Specifically, the storage unit 25 includes a shooting information database, which will be described later.
The storage unit 25 also functions as a storage means and stores theoretical calculation formulas.
The storage unit 25 also stores a learning model that is constructed from the subject information and the past shooting information and that calculates signal values of the small-angle scattering image and/or the differential phase image. In the following description, the term "model" refers to the learning model.

(Shooting condition calculation processing)
The photographing condition calculation process is a process in which the control unit 21 calculates the photographing conditions based on the subject information, past photographing information and/or theoretical calculation formulas. After calculating the photographing conditions, the control unit 21 functions as a display control means and executes a photographing condition display process for displaying the photographing conditions on the display unit 23.
The photographing condition calculation process and the photographing condition display process are executed by the control unit 21 in cooperation with a program stored in the storage unit 25 .

First, an image of the photographing condition calculation process will be described with reference to Fig. 5. The image shown in Fig. 5 is an image in which subject information is input, and the control unit 21 functioning as a calculation means performs theoretical calculations using theoretical formulas and/or calculations from data such as past photographing information, and outputs recommended photographing conditions.
The input subject information includes, for example, material, composition, structure, solid/composite material, fiber length, fiber diameter, defect information, and problem background.
The shooting conditions that are output include, for example, transmittance, scattering intensity, X-ray irradiation conditions, tube voltage, mAs value, number of shots (orientation shooting), number of shots (tiling shooting), arrangement of the shooting field of view (tiling shooting), and whether shooting is possible.
This allows the user to easily determine more appropriate shooting conditions for Talbot photography.

Example 1
Next, the flow of the shooting condition calculation process will be described with reference to FIG.
In Example 1, a user wants to know whether defects (voids) in aluminum die-cast products can be detected by Talbot images. The subject information in Example 1 is as follows: name: aluminum die-cast, category: metal part, thickness in the optical axis direction: 60 mm, and dimensions within the subject table: 100 mm x 100 mm.

First, the user uses the operation unit 22 to input subject information into the input screen shown in FIG. 7 displayed on the display unit 23. The control unit 21 accepts the subject information (step S1). At this time, the control unit 21 functions as a receiving unit.

Here, the input screen shown in FIG. 7 will be described.
The name field A1 is a field where the user inputs the name of the subject. The name of the subject is, for example, the product name or general name of the subject being photographed. The user can input the name manually, or by selecting from a selection of options using a pull-down menu, or by other methods. The category field A2 is a field where the user inputs the category of the subject. The category of the subject is, for example, a general classification of the subject. General classifications include resin/fiber-reinforced resin/electronic components/metal components, etc. The user can input the category to which the subject being photographed is thought to belong by manually inputting the name, or by selecting from a selection of options set in advance using a pull-down menu, or by other methods.

The element field A3 is a field where the user inputs the material and elements that make up the subject. In the following explanation, the contents input in the element field A3 are referred to as characteristics (elements). The material and element fields may be input manually, or may be selected from a pre-set element table or representative material examples (CFRP, GFRP, etc.). The shape field may be input manually, or may be selected from pre-set options (rectangular prism, sphere, columnar, plate, cylinder, etc.) using a pull-down menu. When the shape field is an option, the information to be input in the subject table surface dimension field changes depending on the set shape. For example, if "rectangular prism" is input, the in-plane dimension information can be input, but if "sphere" is input, the radius information can be input. The thickness field in the optical axis direction is a field where the dimension in the z-axis direction in FIG. 1 is input. The subject table surface dimension field is a field where the in-plane dimension, that is, the xy plane dimension in FIG. 1 is input. For example, if "rectangle" is selected in the shape field, x-dimension x y-dimension = X mm x Y mm can be input, and if sphere is selected, radius = R mm can be input. It may also be possible to directly load CAD data, etc., to input more complex shapes.

The contained substance field A4 is a field where the user inputs information about the contained substances contained within each element. The contained substances are, for example, packing materials, additives, and fillers. In the following explanation, the content input in the element field A3 is referred to as the characteristic (contained substance). The composition field may be input manually or may be input by selecting from a pre-set composition table. The shape field may be input manually or may be input by selecting from pre-set options (spherical, cylindrical, plate-like, etc.) using a pull-down menu. If "sphere" is selected in the shape field, information such as "radius" can be input in the field below the shape field, and if "cylindrical" is selected, information such as "diameter" and "orientation" can be input in the field below the shape field. The concentration field is a field where the concentration of the contained substance is input. If it is considered that no contained substance is contained, the contained substance field A4 may be left blank or deleted.

The visualization target field A5 is the target that the user wants to visualize. Such targets are, for example, cracks, voids, fibers, etc. The material/element field is a field in which the materials and elements that make up the visualization target are input. For example, air, fibers, etc. The shape field may be input manually, or may be input by selecting from pre-defined options (cuboid, sphere, columnar, plate, etc.) using a pull-down menu. If "sphere" is selected in the shape field, information such as "radius" can be input in the field below the shape field, and if "columnar" is selected, information such as "diameter" and "orientation" can be input. If the dimensions of the target to be visualized are unknown, the field may be left blank.
It is also possible to add or delete the number of elements, the substances contained in the elements, and their characteristic values for each subject.

The add characteristic button B1 is a button for adding an input field for a characteristic (element) or a characteristic (contained substance) to the element field A3 or the contained substance field A4.
The characteristic deletion button B2 is a button for deleting the input field of the characteristic (element) or characteristic (contained substance) in the element field A3 or the contained substance field A4.
The element addition button B3 is a button for adding an element field A3.
The element deletion button B4 is a button for deleting the element column A3.
The add substance button B5 is a button for adding a substance column A4.
The Delete Substances button B6 is a button for deleting the Substances column A4.
7, when element 1 is specified in element field A3, pressing the Add Ingredient Button B5 or the Add Property Button B1 adds an ingredient or property to element 1. Similarly, when element 1 is selected in element field A4, pressing the Add Property Button B1 adds a property to element 1.

The optical photo acquisition button B7 is a button that photographs the subject placed on the subject table 13 from at least one direction and acquires an optical photo. The acquired optical photo is displayed in the optical photo display area A6. By recognizing the subject part in this image, information such as the thickness and dimensions of the subject can be automatically calculated and reflected on the input screen. The user can also manually specify dimensions from the acquired optical photo. The photo can also be acquired by reading and displaying a photo of the sample taken separately.

The Import Drawing button B8 is a button for importing drawing information into the input screen when there is drawing information. For example, the thickness and dimensions of the subject, and the material type that constitutes the subject can be reflected on the input screen. Specifically, when the Import Drawing button B8 is pressed, a file selection dialog box is opened, and CAD data, etc. can be selected. The imported drawing information is displayed in the drawing display field A7.
The file load button B9 is a button for loading a text file containing information such as the components and substances contained in the subject, instead of manually inputting the information, and reflecting the information on the input screen.
The subject background field A8 is a field for the user to input and record the background and subject that led to wanting to take the photograph or taking the photograph.
The purpose column A9 is a column where the user inputs the purpose of the photography.
The calculation start button B10 is a button for proceeding with the photographing condition calculation process based on the input subject information.

Next, the user uses the operation unit 22 to press the calculation start button B10 displayed on the display unit 23. The control unit 21 accepts the pressing of the calculation start button B10 (step S2). The shooting condition calculation process proceeds to step S3.

Next, the control unit 21 searches the photography information database for photography information that matches or is similar to the input subject information (step S3). At this time, the control unit 21 functions as an extraction unit.
The search method may involve, for example, extracting shooting information that matches the name and category of the input object information from the shooting information database, and then searching for shooting information that matches or is similar to the object's material, thickness, etc.
If there is photographic information that is similar or coincident with the subject information (step S4; YES), the amount of scattering is calculated based on the photographic information in parallel with steps S6 to S8 (step S5). In this embodiment, it is assumed that there is no photographic information that coincides or is similar to the subject information, and the process proceeds to the next step.
If there is no shooting information similar or matching to the subject information (step S4; NO), the shooting condition calculation process does not calculate the amount of scattering based on the shooting information (step S5), and proceeds to step S9.
In the first embodiment, it is assumed that there is no shooting information similar or matching to the subject information, and therefore step S5 is skipped.
In the embodiment, the process of steps S4 to S5 and the process of steps S6 to S8 are performed in parallel, but the process of steps S4 to S5 and the process of steps S6 to S8 may each be performed independently.

Next, the control unit 21 calculates the transmittance (step S6). At this time, the control unit 21 functions as a calculation unit.
The control unit 21 calculates the transmittance of each X-ray energy when passing through the subject from the input subject information. In the transmittance calculation, the control unit 21 may treat the X-ray energy as polychromatic or may calculate as monochromatic. Here, for simplicity, the case of calculating as monochromatic will be described. First, the linear absorption coefficient is derived from the information of "material/element" of "element" in the input subject information. The linear absorption coefficient can be derived by referring to databases such as NIST (https://physics.nist.gov/PhysRefData/FFast/html/form.html) and science chronology and collating it with the subject information. The following formulas can be used for the calculation, for example.
(TR: transmittance, λ: wavelength (corresponding to energy), μ: linear absorption coefficient, t: thickness, i: type of element constituting the subject)

When there are multiple elements, the linear absorption coefficient for each element is derived, and the transmittance can be derived by substituting the linear absorption coefficient for each element together with the thickness of each element into Equation 1. The range of energy (maximum and minimum values) to be substituted into Equation 1 may be determined within a certain range based on the tube voltage and type of additional filter selectable for the X-ray source mounted on the device that the user can use. In this embodiment, the following calculations are performed assuming that the energy range is from 50 to 100 keV.
In Example 1, since there is only one type of element and the material is aluminum, the linear absorption coefficient of aluminum is derived and substituted into Equation 1 together with the thickness (=60 mm), and the subject transmittance for each X-ray energy is as shown in the following Figure 8. Figure 8 is a graph in which the horizontal axis is X-ray energy and the vertical axis is transmittance [%]. The solid line indicates the transmittance calculated based on the subject information input in this example.

Next, the control unit 21 determines whether the transmittance is equal to or greater than a threshold value (step S7).
A transmittance threshold is set as one of the criteria for whether Talbot imaging is possible or difficult. This threshold may be set in advance or may be set to an arbitrary value by the user. In step S6, the control unit 21 performs a theoretical calculation of the transmittance of the subject to check whether there is a condition in which the transmittance exceeds the threshold. If there is a condition in which the transmittance exceeds the threshold (step S7; YES), the process proceeds to the next step S8 for that condition. If there is no condition in which the transmittance exceeds the threshold (step S7; NO), it is determined that imaging is difficult with the currently set X-ray energy, and the imaging condition calculation process proceeds to step S14.
In addition, at the point in time when it is determined that photography is difficult, the calculation of countermeasures (step S14) may be performed without performing the subsequent calculation step S8 (calculation of the visibility rate), or the calculation of countermeasures (step S14) may be performed while performing the subsequent calculation step S8 (calculation of the visibility rate).
In Example 1, if the transmittance threshold is 10% (dotted line in FIG. 8), it can be seen that even at maximum energy (dotted line in FIG. 8), which is the condition under which the transmittance of the subject in this example is at its maximum, the transmittance is about 6%, which does not exceed the threshold. Therefore, since there are no shooting conditions for this subject under which the transmittance exceeds the threshold, it is determined that it is difficult to shoot this subject. In Example 1, the process proceeds to step S14, where a countermeasure is calculated.

Next, the control unit 21 calculates candidate countermeasures that will enable imaging (step S14). At this time, the control unit 21 functions as a second calculation means. For example, in the case of the subject in Example 1, the calculation of the transmittance based on formula (1) shows that the subject thickness at which the transmittance is ≧10% at the maximum energy of 100 keV is 4.9 cm or less (dotted line in FIG. 5). This calculation derives the subject thickness at which the transmittance exceeds the threshold value. In this example, the subject thickness is the subject condition. When calculating the candidate countermeasures, other parameters that can be adjusted include the X-ray energy (however, this is limited to a range smaller than the maximum tube voltage of the device specifications), the subject material/elements, the composition/shape of the contained substances, and the orientation of the subject during imaging.

Next, the control unit 21 outputs the calculation result (step S15). For example, the control unit 21 outputs the calculation result to the display unit 23 and displays it on the display unit 23 (shooting condition calculation processing), thereby presenting it to the user. For example, the control unit 21 may cause the display unit 23 to display a screen such as that shown in FIG. 9.

The output screen shown in FIG. 9 will be described.
The imaging condition display area A11 is an area for displaying at least one recommended imaging condition.
As imaging conditions, it is conceivable to output the tube voltage, mAs value, thickness of the additional filter, etc.
As a result of the calculation of image quality, transmittance, etc., the shooting conditions are displayed in an order that follows some rule. The rule for the display order may be, for example, displaying in ascending order from the condition with the best image quality, the highest transmittance, and the shortest shooting time. In this embodiment 1, there is no condition that exceeds the threshold value at the time of the transmittance calculation (step S6). Therefore, the condition to be output in the shooting condition display area A11 may be left blank, or the condition with the highest transmittance may be output.
Note that the setting value of the tube voltage displayed on the output screen does not necessarily coincide with the peak position of the X-ray energy distribution irradiated under that setting value. Therefore, the conditions of the tube voltage and additional filter that realize the X-ray energy (100 keV in the first embodiment) that maximizes the image quality and transmittance as a result of the calculation may be calculated separately and displayed in A11.

The calculation result display area A12 is an area for displaying the image quality and the predicted calculation result of the image quality when imaging is performed using the imaging conditions displayed in the imaging condition display area A11. In the first embodiment, only the transmittance is calculated, and only the subject transmittance at the X-ray energy calculated in step S6 is written, and the remaining fields are left blank. The imaging time is the time required for imaging. The time required to acquire one moire image Mo during BG imaging or actual imaging (referred to as the moire image acquisition time) is set in advance. The imaging time can be derived from a calculation formula such as moire image acquisition time x (number of moire images acquired in BG imaging + number of moire images acquired in actual imaging) x number of imaging. The calculation formula is not limited to this, and for example, a calculation formula that additionally takes into account various intervals such as the time for setting up the subject between BG and actual imaging may be used.
In addition, when the photographing method is orientation photographing, it may be possible to display the number of photographs required to achieve a desired orientation angle, the installation position of an appropriate mark for position correction, etc. In addition, when the photographing method is orientation photographing, it is necessary to photograph the BG photograph for each orientation angle, and the timing of the BG photographing may be displayed using text, a timing chart, or a flow chart.

The tiling photography method display area A13 is an area that displays a proposal for the tiling photography method. The tiling photography method display area A13 will be described later. Note that a recommended field of view arrangement for capturing the entire subject with as few shots as possible may be displayed in this area.

The photographing availability display area A14 is an area that displays "available" when there are photographing conditions that make photographing possible as a result of the calculation, and displays "not possible" when there are no photographing conditions that make photographing possible. In the first embodiment, since there were no photographing conditions that make photographing possible, "not possible" was displayed.
In addition, the possibility of photographing the subject may be judged from the viewpoint of the photographing time, S/N, spatial resolution, etc., and the possibility of photographing may be displayed. When the photographing time is used as the criterion for the possibility of photographing, if the photographing time of the calculation result exceeds the upper limit of the photographing time determined by the user or the device specifications, "Not possible" can be displayed, and vice versa. When the S/N is used as the criterion, the possibility of photographing can also be judged by comparing the S/N of the calculation result with the lower limit of the S/N set in advance. Similarly, for the spatial resolution, the possibility of photographing can also be judged by comparing the size of the visualized object with the spatial resolution of the device set in advance.
The cause display area A15 is an area where, if it is determined that photography is not possible as a result of the calculation, the cause of the determination is displayed. In the first embodiment, the cause of the determination is that there is no photography condition where the subject transmittance is equal to or greater than the threshold, so for example, "insufficient transmittance" is displayed.
The countermeasure display area A16 is an area that presents the user with countermeasure candidates that will enable photography if it is determined that photography is not possible as a result of the calculation. In the first embodiment, the condition for photography being possible was "subject thickness ≦ 4.9 cm," so for example, "subject thickness ≦ 4.9 cm" is displayed. If the photography condition is "subject thickness ≦ 4.9 cm," the transmittance is equal to or greater than the threshold, and photography is possible.

The recalculation button B11 is a button for returning to the input screen. When the recalculation button B11 is pressed, the user can re-input the subject information.
The calculation end button B12 is a button for ending the imaging condition calculation process and the imaging condition display process by the control unit 21. When the calculation end button B12 is pressed, the imaging condition calculation process and the imaging condition display process end. When the calculation end button B12 is pressed, the imaging conditions selected by the user are reflected in the X-ray Talbot imaging device 1.
In addition, when the imaging method is tiling imaging, the tiling imaging method and imaging flow may be output as a script together with the display in the tiling imaging method display area A13. The output script is read into the X-ray Talbot imaging device 1, and the X-ray Talbot imaging device 1 can execute tiling imaging based on the read script.

In this embodiment, since the calculated value of the subject transmittance did not exceed the threshold, it was determined that imaging was difficult, and the calculations in steps S8 to S13 were not performed. However, even if the transmittance is low, the calculations in steps S8 to S13 are possible, so they may be performed in parallel with the countermeasure calculation in step S14. In that case, the information output to the output screen in FIG. 9 may be such that at least one or more calculation results in steps S8 to S13 can be displayed in the calculation result display area A12 in addition to the information described in [0070] to [0074]. When multiple exposure conditions and calculation results are displayed, they may be displayed in an order based on the rules described in [0070].

Example 2
Next, the flow of the photographing condition calculation process will be described with reference to Fig. 6. In the second embodiment, it is assumed that the user wants to know the photographing conditions of the subject H having a rib structure provided on a resin plate.
The subject of Example 2 is a flat plate made of resin with a rib structure provided on it, as shown in Fig. 10. The user considers the base of this rib structure to be the area to be inspected (= area of interest), and wants to know whether a void B (Φ = 100 μm) that may be present in this area can be detected in a Talbot image. The resin of subject H is assumed to contain spherical silica filler with a particle size of 2 μm at a concentration of 10 vol% as a contained substance.

First, the user uses the operation unit 22 to input subject information into the input screen shown in FIG. 11 displayed on the display unit 23. The control unit 21 accepts the subject information (step S1). The items on the input screen are the same as those in the first embodiment, so a description thereof will be omitted.

The user uses the operation unit 22 to press the calculation start button B10 displayed on the display unit 23. The control unit 21 accepts the pressing of the calculation start button B10 (step S2). The shooting condition calculation process proceeds to step S3.

Next, based on the input subject information, the shooting information database in the storage unit 25 is searched for shooting information of similar subjects (step S3).

Here, the photographing information database in the storage unit 25 and the search method will be described.
As shown in FIG. 12, the photographing information database in the storage unit 25 stores, for example, the following information:
The shooting date and time is the date and time when the subject was photographed.
The subject information (subject name and category) is the name and category of the subject. The subject information (subject name and category) is used for the search in step S3. The subject information (subject name and category) corresponds to the name column A1 and the category column A2 on the input screen.
Subject information (elements) consists of issue, element, and characteristic (element). Issue is the background that led to the photograph and the problem to be solved. Issue corresponds to issue/background column A8 on the input screen. Elements are the materials that make up the subject, and if the subject is made up of multiple types of elements, the number of elements can be entered in the database. Characteristics (elements) are the characteristic values of each element. Characteristics (elements) include, for example, shape, thickness, and ratio to the subject. Subject information (elements) corresponds to element column A3 on the input screen.
The subject information (containing substances) is the material of the containing substances contained in each element. The characteristics (containing substances) are characteristic values of each containing substance. Examples of the characteristics (containing substances) include shape and size. The subject information (containing substances) corresponds to the containing substances column A4 on the input screen.
The imaging conditions are the conditions specified at the time of imaging, such as the tube voltage and mAs value.
The shooting result is the result of shooting under certain shooting conditions. The shooting result is the signal value, noise, etc. of the obtained image. The shooting result column may also include a sensory evaluation of whether the obtained image has a satisfactory image quality for the user.

A method for searching for shooting information of a similar subject will now be described.
For example, the control unit 21 narrows down the shooting information in the shooting information database in the following order to extract shooting information similar to the input information.
Step 1: The control unit 21 extracts items with matching names and categories.
Step 2: The control unit 21 extracts subjects whose elements match.
Step 3: The control unit 21 extracts items with matching contained substances.
It should be noted that the term "match" includes not only a perfect match but also a partial match.

In the second embodiment, it is assumed that the photographing information database search in step S3 finds that photographing information similar to the input subject information exists (step S4; YES), and the photographing condition calculation process proceeds to step S5.
The control unit 21 calculates the amount of scattering caused by the subject in the following manner: The control unit 21 uses the visibility ratio obtained by Talbot photography or the signal value of small angle scattering as an index of the amount of scattering.
The control unit 21 performs an interpolation calculation using the values of the imaging information extracted in step S3 for each of the values of the thickness of the element of the input object information and the concentration and particle size of the contained substance, and predicts the visibility ratio (small-angle scattering signal value) of the input object (step S5). At this time, the control unit 21 functions as a calculation means.

For example, the control unit 21 predicts the visibility rate using a graph in which the thickness of the subject and the concentration of the contained substance (filler) are variables, using the above-mentioned imaging information database shown in Fig. 13. Note that the following description will be given taking an example in which X-ray energy is 80 keV.
In the following description, experimental values refer to values in past photographing information.
The control unit 21 selects the experimental values on either side of the input subject thickness. Then, it derives an equation for a line connecting the thicknesses at those two points and the experimental value of the visibility ratio (dotted line in FIG. 13). Finally, the control unit 21 uses the input subject thickness between those two points and the equation to determine a predicted value of the visibility ratio.

In the above description, the thickness and the concentration of the contained substance (filler) are used as variables, but the variables are not limited to this.
In addition, in the example of Figure 13, the concentration of the substance contained in the input subject matches the thickness of the subject in the shooting information in the shooting information database, but if they do not match, the control unit 21 estimates the visibility rate by linear interpolation, as in the case of thickness.

Alternatively, the following may be used as a means of estimating visibility.
A model is constructed from similar imaging information extracted from the imaging information database, with various subject information and imaging conditions as explanatory variables and the visibility rate and small-angle scattering signal value to be estimated as objective variables. In this way, it becomes possible to predict the estimated visibility rate and small-angle scattering signal value for each imaging condition when new subject information is input. The accuracy of the model can be improved by providing feedback to the model each time an image of the subject is taken.

Steps S6 and S7, which are executed in parallel with steps S4 and S5, are similar to those in the first embodiment, and therefore the description thereof will be omitted.
In the second embodiment, it is assumed that the transmittance calculated in step S6 exceeds the threshold value, and the photographing condition calculation process proceeds to step S8.

The control unit 21 calculates the amount of scattering caused by the subject using the theoretical calculation formula stored in the memory unit 25 (step S8). At this time, the control unit 21 functions as a calculation means. The control unit 21 inputs the input subject information into the theoretical calculation formula, thereby enabling theoretical prediction of the visibility rate. Examples of the theoretical calculation formula include the formulas described in

Non-Patent Documents

2, 3, 4, and 5.

The control unit 21 judges whether the visibility rate is equal to or higher than a threshold (step S9). In the present invention, a threshold value of the visibility rate is set as one of the criteria for whether photography is possible or difficult. This threshold value may be set in advance or may be set to an arbitrary value by the user.
If there is a condition that causes the visibility rate to exceed the threshold, the photographing condition calculation process proceeds to step S12. If there is no condition that causes the visibility rate to exceed the threshold, the photographing condition calculation process proceeds to step S14.
Here, the predicted visibility rate may be derived from an experimental value in step S5 or from a theoretical calculation in step S8. Which of the two is to be used for the judgment is judged, for example, as follows.
Step 1: When there is no information in the imaging information database and derivation from experimental values is not possible, the control unit 21 adopts a predicted visibility based on a theoretical calculation formula.
Step 2: When it is possible to predict and calculate the visibility rate from the information in the photographing information database, the control unit 21 adopts the predicted visibility value based on the experimental value.
The determination procedure is not limited to the

above procedures

1 and 2, and may be a procedure in which the highest predicted visibility rate is adopted, or the results of

procedures

1 and 2 are presented to the user to allow the user to select.

In the second embodiment, the threshold value of the visibility rate is assumed to be 10% (FIG. 13, dotted line). The predicted visibility rate calculated from the information in the imaging information database is below the threshold value under the conditions shown in FIG. 13 (FIG. 13, estimated value). Therefore, it is determined that imaging is difficult at least under these imaging conditions (tube voltage and additional filter). Therefore, since there are no imaging conditions in which the visibility rate exceeds the threshold value for this subject, it is determined that imaging is difficult for this subject (step S9; NO).

The control unit 21 calculates potential countermeasures that will enable imaging (step S14). At this time, the control unit 21 functions as a second calculation means. For example, the control unit 21 can derive conditions under which the visibility rate exceeds a threshold value by performing an interpolation calculation from experimental values (step S5) or a calculation using a theoretical formula (step S8). Possible parameters to be adjusted include X-ray energy, subject thickness, and the composition/size/concentration of contained substances.

The control unit 21 outputs the calculation result (step S15). For example, the control unit 21 outputs the calculation result to the display unit 23 and displays it on the display unit 23 (shooting condition calculation processing) to present it to the user. For example, the control unit 21 may cause the display unit 23 to display a screen such as that shown in FIG. 14. Each item on the display screen in FIG. 14 is the same as in Example 1, so a description thereof will be omitted.

Example 3
Next, the flow of the photographing condition calculation process will be described with reference to Fig. 6. In the third embodiment, the user wishes to know whether or not a void B (Φ=100 μm) contained in the epoxy resin of the subject H, which is a copper plate C with a thickness of 0.1 mm and an epoxy resin E with a thickness of 3 mm layered thereon, can be detected in a Talbot image. It is assumed that the epoxy resin E contains spherical silica fillers with a particle size of 2 μm at a concentration of 5 vol% as a contained substance.

First, the user uses the operation unit 22 to input subject information into the input screen shown in FIG. 11 that is displayed on the display unit 23. The control unit 21 accepts the subject information (step S1).

Then, the control unit 21 searches the photography information database of the storage unit 25 for photography information of a similar subject based on the input subject information (step S3). In the third embodiment, it is assumed that photography information of a similar subject exists.

Next, the control unit 21 calculates the amount of scattering by the subject using the past imaging information (step S5). In the same manner as the method described in the second embodiment, the control unit 21 estimates the amount of scattering (=visibility rate) from the past imaging information. The control unit 21 searches the imaging information database for similar past imaging results based on information (composition, concentration, thickness) about the filler among the substances that make up the subject inputted on the input screen, and obtains the visibility rate under the closest conditions.
In addition, if there is no imaging information regarding similar concentration/thickness, the control unit 21 can handle this by calculating the interpolation/extrapolation of the visibility rate for both parameters in a manner similar to the procedure described in the second embodiment.

Next, the control unit 21 calculates the subject transmittance in the same manner as in Examples 1 and 2 (step S6). Figure 17 shows the relationship of the transmittance of a copper plate with a thickness of 0.1 mm.

Next, the control unit 21 judges whether the transmittance is equal to or greater than a threshold value (step S7). Assuming that the maximum X-ray energy that can be set is 100 keV and the transmittance threshold value is 10%, similarly to the first and second embodiments, the control unit 21 judges that if the X-ray energy is equal to or greater than 80 keV from the graph of FIG.
It is determined that the threshold value is exceeded (step S7; YES). Note that the graph in Fig. 17 shows the relationship between X-ray energy and transmittance. Therefore, in subsequent calculations, the control unit 21 performs image quality calculations at X-ray energies equal to or higher than this threshold value.

Then, the control unit 21 calculates the amount of scattering by the subject using a theoretical calculation formula (step S8). As in the second embodiment, the control unit 21 estimates the visibility rate using the theoretical calculation formula. Note that the predicted visibility may be performed for all X-ray energies that can be set, or may be performed only for X-ray energies for which the transmittance derived in step S6 is equal to or greater than a threshold value.

Next, the control unit 21 determines whether the predicted visibility rate is equal to or greater than the threshold value (step S9). As in the second embodiment, the control unit 21 determines whether the estimated visibility rate is equal to or greater than the threshold value based on the imaging information or by using a theoretical calculation formula. In the third embodiment, it is determined that the visibility rate exceeds the threshold value at any tube voltage under any imaging condition, and the process proceeds to the subsequent step S10.

Next, the control unit 21 predicts the image quality when shooting is performed under the shooting conditions (step S10). At this time, the control unit 21 functions as a prediction unit. As a specific example, the control unit 21 calculates the image quality ((1) noise, (2) signal value, (3) S/N) using a theoretical calculation formula. The calculation method will be described in order.
The control unit 21 performs calculations of only (1) or (1) to (3) for all conditions (tube voltages and filters) that exceeded the thresholds in step S9.
(1) Theoretical Calculation of Noise The control unit 21 calculates the noise of each image according to a theoretical calculation formula.
The control unit 21 can calculate the relationship between the detector output value and the noise of each image by using, for example, the theoretical formula described in Non-Patent Document 1 as a theoretical calculation formula. The detector output value is proportional to the mAs value of the radiation source. Therefore, the noise value can be predicted by using the mAs value as a variable parameter.
For example, the calculation result for the subject assumed here is as shown in Fig. 18. Fig. 18 is a graph made using the theoretical formula of Non-Patent Document 1. The theoretical formulas for noise of transmittance, phase, and visibility rate are shown in the order of Fig. 18A, Fig. 18B, and Fig. 18C. Note that the transmittance and visibility rate are normalized by the average value.
From this result, the control unit 21 calculates a mAs value that satisfies the required noise level. The control unit 21 calculates the minimum count value (the intersection of the blue line and the gray dotted line) among the count values that satisfy the noise required value (gray dotted line in FIG. 18) set in advance. Note that the required noise may be set for the Talbot images (absorption image, differential phase image, small angle scattering image), or may be set for only one of the images (for example, small angle scattering).
The control unit 21 may end the calculation in step (1) and output the conditions that the noise is equal to or less than a specified value and the shooting time is short on the output screen. The control unit 21 may additionally calculate the signal of the subject in the subsequent steps to calculate the S/N ratio.

(2) Theoretical Calculation of Signal Values If the shape and composition of the visualization target and the composition of the material surrounding the visualization target are specified, the control unit 21 can theoretically calculate the signal values of the visualization target at least for absorption and differential phase images. On the other hand, the control unit 21 may have difficulty performing theoretical calculations for small-angle scattering images. When the calculation is difficult, the control unit 21 searches and extracts similar shooting information from a database of past shooting history, and calculates the signal values.
For example, the control unit 21 can generate a simulation image of a differential phase image and a lateral profile of the assumed void as shown in Fig. 19. Fig. 19A is a simulation image of the signal values of the differential phase image. Fig. 19B is a lateral profile of the signal values of the differential phase image.

(3) Calculation of S/N The control unit 21 can calculate the S/N ratio by taking the ratio between the noise value and the signal value derived in (1) and (2), respectively.

Next, the control unit 21 judges whether the image quality predicted in step S10 satisfies a predetermined image quality condition (step S11). At this time, the control unit 21 functions as a judging unit.
If there is (step S11; YES), the shooting condition calculation process proceeds to step S12.
If not (step S11; NO), the process proceeds to step S 14. The process content of step S14 is the same as that of the second embodiment, except that the visibility rate is replaced with image quality.

Next, the control unit 21 selects the shooting conditions to be output (step S12). At this time, the control unit 21 functions as a selection unit. For example, when an upper limit is set for the number of shooting conditions to be output, the control unit 21 selects shooting conditions with good image quality, starting from the one with the best image quality.

Next, the control unit 21 outputs the photographing conditions (step S13), and the process ends. For example, the control unit 21 outputs the calculation result to the display unit 23 and displays it on the display unit 23 (photographing condition calculation process), thereby presenting it to the user. For example, the control unit 21 may display a screen as shown in Fig. 20 on the display unit 23. Each item on the display screen in Fig. 20 is the same as in Example 1, and therefore description thereof will be omitted.
In the example of the display screen in FIG. 20, multiple shooting conditions are output. When multiple shooting conditions are output, the shooting conditions may be sorted in a predetermined order. The sorting order may be, for example, arranging from the highest image quality, arranging from the condition with the shortest shooting time, arranging from the condition closest to the design value of the shooting device, etc. Some of the top sorted items are displayed on the output screen, and the image noise, S/N, and shooting time for each condition are presented. Even if there is no shooting condition that satisfies the required S/N and noise, sorting and display are performed, and at the same time, a countermeasure to satisfy the required S/N and noise is recommended in the countermeasure display area A16.

Example 4
Next, a fourth embodiment in which the present invention is applied to orientation photography for acquiring the above-mentioned orientation degree image and the like will be described with reference to FIG.
By photographing a subject containing scatterers at multiple angles while changing the relative angle with the lattice, the user can obtain the angle dependence of the signal value of the small-angle image at each angle, and by analyzing this, can obtain orientation analysis images called scattering intensity images, orientation degree images, and orientation angle images. From the scattering intensity image, the user can obtain information about the orientation of the scatterers, such as the in-plane distribution of the scattering intensity of the subject (corresponding to the in-plane distribution of the amount of scatterers), the degree of orientation of the scattering intensity from the orientation degree image (the degree to which scattering is strong in a specific direction or isotropically and randomly), and the direction and angle at which strong scattering occurs from the orientation angle image (corresponding to the orientation direction of the scatterers). This is called orientation photography.

In the case of this orientation photography, the user inputs information such as the material and thickness of the subject, and scattering bodies present inside, and multiple appropriate photography conditions are selected based on simulation (calculation) and a photography information database of photography information, and candidates are presented, which is the same as in the previous embodiments 1 to 3 in the embodiments 4 and onwards.
However, a problem specific to orientation photography is the accuracy of the acquired orientation angle. Figure 21A shows the results of calculations of how the accuracy of the orientation angle changes depending on the S/N ratio of the image.
The calculations were performed assuming that when the relative angle to the grid for a 100 x 100 pixel shooting area was changed to four angles, 0 degrees, 45 degrees, 90 degrees, and 135 degrees, the signal value would be sinusoidal with a peak at an angle of 0 degrees, and random noise was superimposed on the signal value of each pixel (amplitude of the sine wave) to analyze the orientation angle.
Fig. 21A shows a histogram when the noise-to-signal ratio (S/N) is changed from 2 to 10. In Fig. 21A, the horizontal axis represents the orientation angle, and the vertical axis represents the frequency, which corresponds to the number of pixels having the orientation angle corresponding to the angle on the horizontal axis within the analyzed region.
It should be noted that when there is absolutely no noise, all pixels are at 0 degrees because a sine wave having a peak at an angle of 0 degrees is used.
As can be seen from Fig. 21A, when the S/N is low, i.e., when there is a lot of noise, the orientation angle varies over a wide range, and the accuracy of the analysis of the orientation angle deteriorates. Also, as the S/N increases, the width of the histogram becomes narrower, which indicates that the accuracy of the obtained orientation angle increases.
In other words, even when photographing an actual subject, the fluctuation can be reduced and the analysis accuracy can be improved by changing the photographing conditions to reduce noise and increase the S/N ratio. Specific methods for reducing noise include increasing the dose (mAs value) or increasing the number of photographs. By increasing the mAs value, an image with a good S/N ratio can be obtained, and it is expected that the accuracy of the orientation angle distribution will be improved.

Next, Figure 21B shows the results of calculating the histogram when the number of images taken with the same S/N ratio, i.e. the number of relative angles between the grid and the subject being photographed, is changed from 4 to 12 angles. By increasing the number of shooting angles from 4 to 12 angles, the range of variation in the orientation angles is narrowed, and it can be seen that the analysis accuracy of the orientation angles is improved, just as when the dose is increased.

As described above, increasing the mAs value per shot or the number of angles shot at will have disadvantages such as an increase in the number of shots, a longer time required for shooting, and greater tube wear. Therefore, it is preferable to select appropriate conditions according to the purpose of the evaluation. For the analysis accuracy of the orientation angle, a simulation is performed by referring to the predicted and calculated results of the S/N of the small-angle scattering images described in Examples 1 to 3 and the shooting information database of previous shooting information, and information on the expected degree of orientation angle accuracy can be presented for each shooting condition, which can be used as reference information for the user to select appropriate shooting conditions. In addition, at this time, the control unit 21 does not simply present multiple candidates in parallel, but may present recommended conditions from the candidates in order of priority and the reasons therefor, for example, condition A is good if accuracy is prioritized, while condition B is good if the shooting time is to be shortened. At this time, the control unit 21 functions as a selection means.

Example 5
Next, a case will be described in which the user wishes to photograph the entire subject even though the in-plane size of the subject input to the operation unit 22 is larger than the field of view of the photographing device per photograph, as shown in FIG.
In this case, it is necessary to perform tiling photography in which the entire subject is photographed by photographing the subject multiple times while moving it. The function of the control unit 21 will be described below, which presents how to arrange the field of view relative to the subject during tiling photography so that the entire area to be photographed can be photographed with the minimum number of photographs required.

If the size of the subject is larger than the field of view based on the input information on the size of the subject, the control unit 21 presents a proposal for the field of view arrangement when performing tiling photography, as shown in FIG. 22A.
In addition, the display of the tiling photography arrangement may be switched ON/OFF at the user's choice. In other words, even if the subject is larger than the field of view, tiling photography may be turned OFF if tiling photography is not necessary.
In addition, the orientation of the subject at the time of shooting, the area of the subject that is to be photographed, or the area of the subject that is not required to be photographed may be input by some method such as a mouse, coordinate specification, or CAD data. The orientation of the subject at the time of shooting refers to which part of the subject is arranged in the horizontal or vertical direction. The area of the subject that is to be photographed refers to a case where it is sufficient to photograph only a certain area of the subject, not the entire subject. The area of the subject that is not required to be photographed refers to an area of the entire subject that is not required to be photographed, such as an edge of the subject or a metal member, which is difficult to photograph using a Talbot camera, and is therefore not required to be photographed by the user. For example, FIG. 22B shows a schematic diagram of a case where the user inputs that a part of the sample (F) does not need to be photographed, and the photographing fields of view V1, V2, and V3 are presented to the user so that the entire area other than F can be photographed.
Furthermore, as shown in Fig. 22B, when calculating the arrangement of the fields of view, the fields of view may be arranged so as to cover only the area to be photographed, rather than the entire subject, or the fields of view may not be arranged for areas that do not need to be photographed. This allows the number of photographed fields of view to be reduced, shortening the photographing time and suppressing tube wear.
In addition, when aligning individual images after shooting, it is easier for the control unit 21 or the user to perform alignment if the images overlap partially as shown in FIG. 22. The greater the overlap amount of the fields of view, the more information is available for alignment, making alignment easier, but on the other hand, if the overlap amount of the fields of view is too large, the number of fields of view required to shoot a subject of a certain size increases, which is not preferable. This overlap amount is preferably set to about 3 to 10 mm, but it may be possible to set a range larger or smaller than this range. It is preferable to present some value, such as 5 mm, as an initial value, and allow the user to change it. Also, by setting a negative value, tiling shooting may be performed with a certain gap between the fields of view. In this way, it is possible to shoot a subject that is several times larger than the field of view with a small number of shots to roughly grasp the overall trend.

In addition, in the case of a subject that has a distinctive outline or shape and little change in signal value, by placing some sort of alignment mark (alignment mark M) in the overlapping area of the fields of view (V1 to V4) as shown in FIG. 22 and photographing the subject at the same time, the control unit 21 or the user can more easily align the fields of view manually or automatically. When presenting the layout of the fields of view, the control unit 21 may also present a recommended position for placing the alignment mark M, taking into consideration the overlapping areas of the photographed fields of view.

In addition, when actually taking an image, the subject and the sample may be placed manually one by one on the subject table 13 alongside the sample. Alternatively, as an alternative method, the subject and alignment marks may be placed on a plate that transmits X-rays and scatters little, such as a transparent acrylic plate, and then fixed with tape or the like, and the acrylic plate may then be placed on the subject table 13 of the imaging device, which is preferable as it makes it easier to set up the actual subject.
To assist with such positioning, it would be good to have a function to print out necessary information such as contours that indicate the position of the subject, the positions of alignment marks, and the position of the field of view in actual size, or to display it on a panel such as a display.
By placing an acrylic plate on top of a printout or a panel that is placed horizontally on a desk and displays information, and then arranging the subjects and alignment marks so that they overlap the displayed arrangement and fixing them in place as necessary, it is possible to easily realize the presented arrangement of the subjects.

It is also preferable that the shooting times of adjacent fields of view are as close as possible, because as time passes, subtle changes occur in the images and signal values obtained due to environmental changes such as temperature changes, and this can result in noticeable seams when tiled.
To avoid such a situation, the control unit 21 may present not only the arrangement of the fields of view to be tiled, but also the desired shooting order at the same time.

In addition, because the joints between the fields of view are made by arranging images that were taken separately, it is easy for signal values to change due to the joints being joined together. Also, positional deviations are likely to occur when joining the images.
Therefore, when inputting subject information, a function may be provided that allows the user to input an area that is desired to be photographed in one field of view as much as possible and an area where seams of the fields of view are desired to be avoided as much as possible. When this input is received, when calculating the tiling of the fields of view, the control unit 21 calculates the field of view arrangement so that seams of the fields of view are not located in that area as much as possible and presents it to the user. This makes it possible to photograph according to the user's wishes.
Also, there may be a function that allows the user to see the presented field of view layout and correct it to a desired layout by moving the position of the field of view with a mouse, etc. In that case, the field of view specified by the user is used as a reference, and the fields of view are arranged at appropriate intervals around it, so that a shooting field of view layout that satisfies both the user's desire and shooting with a small field of view can be presented to the user.

Furthermore, the control unit 21 may temporarily save the presented visual field arrangement in a file so that the visual field arrangement and even the imaging conditions can be recalled and executed at a later date. The control unit 21 may also recall previous saved information and then use it by modifying a part of it by the control unit 21 or the user. Information may also be input to the X-ray Talbot imaging device 1 using a file and used during actual imaging. Information may also be transmitted directly to the X-ray Talbot imaging device 1 via a wireless/wired network without going through file storage. In this case, not only the visual field arrangement but also the imaging conditions may be transmitted.

Example 6
If the size of the subject is larger than the size of one field of view and it is desired to capture the orientation of the entire subject, it is necessary to perform the tiling capture described in Example 5 multiple times while changing the relative angle between the grid and the subject.
When taking a photograph by changing the relative angle between the grid and the subject, the subject's position will change, and the field of view arrangement will need to be reconsidered accordingly.
Therefore, in Example 5, even when the subject is rotated by a specified angle, by presenting an appropriate shooting field of view arrangement, it is possible to perform tiling shooting with a different relative angle between the subject and the grid.
For example, the arrangement in FIG. 23A is set to a relative angle of 0 degrees with respect to the grid, and FIG. 23B shows an example of the field of view arrangement when the subject is rotated 45 degrees to capture an image with a relative angle of 45 degrees with respect to the grid.
In addition, although not shown in the figure, when the subject is similarly rotated 90 degrees or 135 degrees, the user is presented with a shooting field of view arrangement that matches the orientation and arrangement of the sample at that time.The user can then use this to take images at multiple angles and tile the obtained shooting results, thereby obtaining multiple tiled images with different relative angles between the grid and the subject.
Furthermore, by performing orientation analysis using the multiple tiling images, the user can obtain orientation results for a large-area subject that is larger than the imaging field of view size.

Example 7
As described in Example 5, when tiling, there is a risk that slight misalignment (subpixel to several pixels) may occur when aligning the captured images of each field of view, or that changes in signal intensity may occur at the seams.
When orientation analysis is performed using images captured by tiling photography, such deviations and changes in signal values may adversely affect the results of the orientation analysis. For example, when orientation analysis is performed using tiling images obtained by tiling photography as in Figure 23 of Example 6, it is unavoidable that the images captured by tiling photography at each angle used for orientation analysis have seams.
However, as shown in Fig. 24, when orientation analysis is performed by first photographing the upper left region of the subject at 0 degrees, 45 degrees, 90 degrees, and 135 degrees, there are no tiling joints in the images of each angle used for orientation analysis, and orientation analysis results can be obtained without the risk of errors due to misalignment or changes in signal strength during tiling. At this time, an orientation analysis image within the inscribed circle of the photographing field of view shown by the dotted line in Fig. 24 is obtained. Then, such photographing is also performed at other positions within the subject, for example, the lower right region of the subject as shown in Fig. 24, and further, although not shown, it is performed over the entire region in which an orientation analysis image within the sample is to be obtained, and then the orientation analysis images obtained at each photographing position are tiled, so that the user can obtain an orientation analysis image of the entire subject larger than the field of view without the risk of errors due to tiling joints.
Therefore, the control unit 21 can assist the user in obtaining orientation photography results of the entire subject by presenting the user with the arrangement of the photography field of view, the order of photography, the photography time required at that time, etc. The control unit 21 may also save the presented field of view arrangement and photography procedure in a file or transmit it to the Talbot photography device so that it can be reused or used for actual photography.

(Feedback Processing)
A feedback (FB) input screen is shown in Fig. 25. After the user photographs a subject using the X-ray Talbot imaging device 1, the control unit 21 causes the display unit 23 to display a feedback input screen as shown in Fig. 25, which allows the user to feed back the results of the photographing including the image quality.
As for image quality indicators, there are indices that can be numerically derived from pixel values and indices that allow a user to visually and sensorily evaluate an image, as described below.
The above numerical and sensory image quality results can also be additionally recorded in the photography information database together with the subject information and photography parameters.

First, the numerical image quality index will be described.
Numerical image quality indicators include: (1) S/N, (2) visibility rate, and (3)
Transmittance, (4) Visibility × √Transmittance, etc.
The numerical image quality index may be calculated for the entire image or for a portion of the image.
When performing calculations on a partial region, the calculation region can be set by the user manually setting the region of interest on the image, or by automatically recognizing and setting a region that meets a certain definition, such as a blank area or a low image quality area.
The blank area is an area where no subject is captured. The blank area may be specified manually by the user or automatically by contour detection or other methods. The blank area may be used as the image quality calculation area in its entirety, or a portion of it may be specified.
The display of low image quality areas will now be described. The control unit 21 can calculate low image quality areas in at least one of the three Talbot images (absorption image, differential phase image, small angle scattering image) acquired with certain imaging parameters, and display the areas on the display unit 23 in a framed state to display to the user. At this time, the control unit 21 functions as a visualization means for visualizing the low image quality areas. This can also be used as a criterion for determining whether the images and signals confirmed in the images are reliable.
The calculation method for the low image quality part will be described. The low image quality part is defined by the following conditions, for example, and can be determined by automatically or manually searching for an area that satisfies this definition. The conditions are: (1) an area where the transmittance/visibility rate is significantly lower than the minimum required value; (2) an area where the S/N is significantly lower than the S/N of the non-transparent part; (3) an area where the S/N is significantly lower than a standard S/N set in advance.

Next, the sensory image quality index will be described. As an index of sensory image quality, the user can judge the quality of the image based on their own criteria. The judgment can be input to the control unit 21 using the operation unit 22 so that the better the image quality, the greater the number of numbers or symbols. If the user does not make a judgment, it is recorded in the memory unit 25 as "no evaluation."

(Signal value prediction using a model)
As described above, the accuracy of the model can be improved by constructing a model in which various object information and shooting conditions are used as explanatory variables and the visibility rate and small-angle scattering signal value to be estimated are used as objective variables, and having the model learn. In the following description, a small-angle scattering image is used as an example, but is not limited to a small-angle scattering image. As a method for constructing and updating this learning model, a method described in [0084] can be considered in which a model is constructed from similar shooting information extracted from the shooting information database in which various object information and shooting conditions are used as explanatory variables and the visibility rate and small-angle scattering signal value to be estimated are used as objective variables.
However, this method is only possible once a certain number of photographic examples of subjects in the same category have been accumulated in the database. When photographic examples are scarce and the amount of data is small, it is possible to start with a model based on the theory described below.
For example, the following formulas (2) to (4) are theoretical formulas described in Non-Patent Document 2 for small-angle scattering signal values, which assume a model in which spherical scatterers are randomly distributed in a certain medium. Using these formulas, it is possible to calculate the signal value (theoretical value) versus particle diameter when the scatterers are assumed to be spherical and randomly distributed. The signal value versus particle diameter is represented by the curve in the graph in FIG.

Furthermore, the signal values (experimental values) obtained when a user actually took a Talbot photograph are displayed as points in Figure 26. The subject photographed was a resin in which spherical silica particles were mixed and solidified. As can be seen from Figure 26, formulas (2) to (4) closely reproduce the change in signal value versus particle size obtained in the experiment.
However, in a real subject, the shape and distribution of particles may differ from the assumptions of the model, and the theoretical value and the experimental value may diverge. In other words, an increase in the number of divergent points suggests that a parameter other than the parameter (particle diameter) assumed by the theoretical formula affects the signal value. Therefore, if there are an increasing number of cases where the theoretical value and the experimental value diverge, a new model formula may be created using the subject information entered by the user, in which a parameter (such as particle shape) other than the parameter (such as particle diameter) used until then is added as a new explanatory variable, and this may be used to predict the signal value of the subject in question.
When the theoretical value and the experimental value deviate from each other, the control unit 21 (calculation means) may calculate a degree of deviation indicating the degree of deviation. For example, the degree of deviation may be calculated by dividing the number of experiments in which the theoretical value and the experimental value deviate from each other by a predetermined value or more by the total number of experiments.

(effect)
As described above, the X-ray Talbot imaging condition calculation device 2 is an X-ray Talbot imaging condition calculation device 2 that calculates imaging conditions in a Talbot imaging means (X-ray imaging system 100) that captures a small-angle scattering image and/or a differential phase image of a subject, and includes a receiving means (control unit 21) that receives input of subject information, and a calculation means (control unit 21) that calculates imaging conditions based on the subject information, past imaging information, and/or theoretical calculation formula. This allows a user to easily determine more appropriate imaging conditions and an arrangement of an imaging field of view in Talbot imaging.

The calculation means (control unit 21) also includes a calculation means (control unit 21) that calculates a predetermined characteristic amount based on past shooting information and/or a theoretical calculation formula, and a selection means (control unit 21) that selects shooting conditions based on the calculated characteristic amount. This allows the user to easily determine more appropriate shooting conditions for Talbot photography based on the selected shooting conditions.

The X-ray Talbot imaging condition calculation device 2 also includes a second calculation means (controller 21) that calculates subject conditions in subject information that satisfy the specified image quality conditions when the determination means (controller 21) determines that imaging conditions that satisfy the specified image quality conditions cannot be obtained. This allows the user to easily determine more appropriate imaging conditions for Talbot imaging without having to perform test imaging of the subject in advance.

The X-ray Talbot imaging condition calculation method is an X-ray Talbot imaging condition calculation method using an X-ray Talbot imaging condition calculation device that calculates imaging conditions in a Talbot imaging means that captures a small-angle scattering image and/or a differential phase image of a subject, and includes a reception step (step S1) for receiving input of subject information, and a calculation step (steps S5, S6, S8) for calculating imaging conditions based on the subject information, past imaging information, and/or theoretical calculation formulas. This allows the user to easily determine more appropriate imaging conditions for Talbot imaging.

The X-ray Talbot imaging system 100 also includes a radiation source, multiple gratings, and a radiation detector arranged in the radiation irradiation axis direction, and includes a Talbot imaging means (X-ray Talbot imaging device 1) that captures at least a small-angle scattering image and/or a differential phase image of a subject based on a moiré fringe image obtained by irradiating a subject arranged in the radiation irradiation axis direction with radiation from the radiation source and capturing the image, a receiving means (control unit 21) that receives input of subject information, and a calculation means (control unit 21) that calculates the imaging conditions based on the subject information and past imaging information. This allows the user to easily determine more appropriate imaging conditions for Talbot imaging.

The program also causes the computer of the X-ray Talbot imaging condition calculation device 2, which calculates the imaging conditions in the Talbot imaging means for capturing small-angle scattering images and/or differential phase images of the subject, to function as a receiving means (control unit 21) that receives input of subject information, and a calculation means (control unit 21) that calculates the imaging conditions based on the subject information, past imaging information, and/or theoretical calculation formulas. This allows the user to easily determine more appropriate imaging conditions for Talbot imaging.

The above describes an embodiment of the present invention, but the description of the above embodiment is a preferred example of the present invention and is not intended to be limiting.

For example, in the above, the X-ray Talbot radiography condition calculation device 2 equipped with the display unit 23 also functions as an image display device, but the X-ray Talbot radiography condition calculation device and the image display device may be separate devices. Specifically, the image display device may perform only display processing, and various processes and information management may be performed by a separate X-ray Talbot radiography condition calculation device. For example, the X-ray Talbot radiography condition calculation device may be a cloud, and only display processing may be performed by the image display device.

In addition, in the above explanation, examples have been disclosed in which a hard disk or a non-volatile semiconductor memory is used as a computer-readable medium for the program according to the present invention, but this is not a limitation. Portable recording media such as CD-ROMs can also be used as other computer-readable media.

In addition, the detailed configuration and operation of each device may be modified as appropriate without departing from the spirit of the invention.

This disclosure can be used in an X-ray Talbot imaging condition calculation device, an X-ray Talbot imaging condition calculation method, an X-ray Talbot imaging system, an X-ray Talbot imaging condition display device, and a program.

1 X-ray Talbot imaging device (Talbot imaging means)
2 X-ray Talbot imaging condition calculation device 11 X-ray generator 11a X-ray source 12 Source grating (G0 grating)
13 Subject stage 14 1st grid (G1 grid)
15 Second lattice (G2 lattice)
16 X-ray detector (FPD)
21 Control unit (acceptance means, calculation means, calculation means, selection means, prediction means, determination means, extraction means, display control means, second calculation means, calculation means, feedback means, visualization means)
22 Operation unit 23 Display unit (display means)
24 Communication unit 25 Storage unit (storage means)
100 X-ray imaging system H Subject S Slit Mo Moire image

Claims

1. An X-ray Talbot imaging condition calculation device that calculates imaging conditions in a Talbot imaging means that captures a small-angle scattering image and/or a differential phase image of a subject, comprising:
A receiving means for receiving input of subject information;
A calculation means for calculating a photographing condition based on the subject information, past photographing information and/or a theoretical calculation formula;
An X-ray Talbot radiography condition calculation device comprising:
The calculation means includes:
A calculation means for calculating a predetermined feature amount based on past photographing information and/or a theoretical calculation formula;
A selection means for selecting the photographing conditions based on the calculated feature amount;
2. The X-ray Talbot radiography condition calculation device according to claim 1, further comprising:
The X-ray Talbot imaging condition calculation device according to claim 2, wherein the calculation means includes a prediction means for predicting the image quality of an image when captured based on the imaging conditions.
The calculation means includes a determination means for determining whether the predicted image quality satisfies a predetermined image quality condition,
4. The X-ray Talbot imaging condition calculation device according to claim 3, wherein the selection means selects imaging conditions that provide image quality that is determined to satisfy the predetermined image quality condition.
The X-ray Talbot imaging condition calculation device according to claim 4, wherein the selection means selects imaging conditions that allow imaging to be completed within a predetermined imaging time.
The X-ray Talbot imaging condition calculation device according to claim 2, wherein the selection means selects imaging conditions based on the analytical accuracy of the orientation angle.
The X-ray Talbot imaging condition calculation device according to claim 1, wherein the subject information includes at least one of the following: thickness of the subject, composition of the material constituting the subject and its ratio to the subject, information on substances contained in each material, and composition, shape, and size of a region of interest in the subject.
The X-ray Talbot imaging condition calculation device according to claim 1, wherein the subject information includes defect information of the subject.
The X-ray Talbot imaging condition calculation device according to claim 1, further comprising a storage means for storing the past imaging information in association with subject information of a subject imaged using the past imaging information.
The X-ray Talbot imaging condition calculation device according to claim 9, wherein the storage means stores a theoretical calculation formula.
The X-ray Talbot imaging condition calculation device according to claim 9, wherein the calculation means includes an extraction means for searching the storage means for past imaging information that matches or is similar to the subject information, and extracting imaging conditions in the matching or similar past imaging information.
The X-ray Talbot imaging condition calculation device according to claim 1, further comprising a display control means for displaying the imaging conditions on a display means.
a display control means for displaying the photographing conditions on a display means;
5. The X-ray Talbot imaging condition calculation device according to claim 4, wherein said display control means displays the imaging condition selected by said selection means.
a display control means for displaying the photographing conditions on a display means;
5. The X-ray Talbot imaging condition calculation device according to claim 4, wherein said display control means, when there is no imaging condition that satisfies a predetermined image quality condition, causes said display means to display that effect.
The X-ray Talbot imaging condition calculation device according to claim 4, further comprising a second calculation means for calculating subject conditions in subject information that satisfy the predetermined image quality conditions when the determination means determines that imaging conditions that satisfy the predetermined image quality conditions cannot be obtained.
The X-ray Talbot imaging condition calculation device according to claim 3, further comprising a calculation means for calculating the degree of discrepancy between the image quality predicted when imaging is performed based on the imaging conditions and the image quality of the image captured based on the imaging conditions.
The X-ray Talbot imaging condition calculation device according to claim 16, further comprising a feedback means for providing feedback to the theoretical calculation formula based on the deviation.
A learning model is further provided that calculates a signal value of a small angle scattering image and/or a differential phase image constructed from the subject information and the past shooting information,
18. The X-ray Talbot imaging condition calculation device according to claim 17, wherein the calculation means calculates the imaging conditions by using the learning model.
The X-ray Talbot imaging condition calculation device according to claim 18, wherein the feedback means corrects the learning model based on at least one of the deviation degree, the original theoretical calculation formula, and the subject information used in the calculation.
The X-ray Talbot imaging condition calculation device according to claim 1, further comprising a visualization means for visualizing low-image-quality areas of the captured image.
The X-ray Talbot imaging condition calculation device according to claim 1, wherein the calculation means presents the arrangement of the imaging field when imaging a sample larger than the imaging field.
The X-ray Talbot imaging condition calculation device according to claim 21, wherein the arrangement of the imaging field of view is an arrangement of the imaging field of view for each imaging angle that indicates the position of the subject relative to the X-ray Talbot imaging device.
1. An X-ray Talbot imaging condition calculation method using an X-ray Talbot imaging condition calculation device that calculates imaging conditions in a Talbot imaging means that captures a small angle scattering image and/or a differential phase image of a subject, comprising:
A receiving step of receiving input of subject information;
a calculation step of calculating a photographing condition based on the subject information, past photographing information and/or a theoretical calculation formula;
The X-ray Talbot radiography condition calculation method includes the following:
a Talbot imaging means which comprises a radiation source, a plurality of gratings, and a radiation detector arranged in a direction of a radiation irradiation axis, and which captures at least a small-angle scattering image and/or a differential phase image of a subject based on a Moiré fringe image obtained by irradiating a subject arranged in the direction of the radiation irradiation axis with radiation from the radiation source and capturing the image;
A receiving means for receiving input of subject information;
A calculation means for calculating a photographing condition based on the subject information and past photographing information;
An X-ray Talbot imaging system comprising:
a computer of an X-ray Talbot imaging condition calculation device that calculates imaging conditions in a Talbot imaging means that captures a small angle scattering image and/or a differential phase image of a subject,
A receiving means for receiving input of subject information;
a calculation means for calculating a photographing condition based on the subject information, past photographing information and/or a theoretical calculation formula;
A program that functions as a
An X-ray Talbot image display device having a display unit that displays the imaging conditions calculated by the calculation means of the X-ray Talbot imaging condition calculation device described in claim 1.