JP6935854B2 - How to adjust the grid - Google Patents

Description

The present invention relates to a method for adjusting a grid, and more particularly to a method for adjusting a grid used in an X-ray phase imaging apparatus that produces a phase contrast image including at least one of an absorption image, a phase differential image, and a dark field image.

Conventionally, there is known a method for adjusting a grid used in an X-ray phase imaging apparatus that generates a phase contrast image including at least one of an absorption image, a phase differential image, and a dark field image. Such an X-ray phase imaging apparatus is disclosed in, for example, International Publication No. 2018/016369.

International Publication No. 2018/016369 is irradiated with an X-ray source, an X-ray from the X-ray source, a first lattice for forming a self-image, and an X-ray that has passed through the first lattice. An X-ray phase imaging apparatus including a second lattice and a detection unit that detects X-rays that have passed through the second lattice is disclosed. In the X-ray phase imaging apparatus of International Publication No. 2018/016369, a phase contrast image including an absorption image, a phase differential image and a dark field image is generated based on the X-ray intensity signal detected by the detection unit.

In the X-ray phase imaging device of International Publication No. 2018/016369, the adjustment mechanism for adjusting the position of the first grid or the second grid and the adjustment mechanism for the first grid based on the moire fringes detected by the detection unit. It is provided with a control unit for adjusting the misalignment or the misalignment of the second grid. As a result, in the X-ray phase imaging device of International Publication No. 2018/016369, when unintended moire fringes occur, the misalignment of the first grid or the misalignment of the second grid so as to eliminate the unintended moire fringes ( By adjusting (misalignment between the first grid and the second grid), deterioration of the image quality of the captured image due to unintended moire fringes is suppressed. The X-ray phase imaging apparatus of International Publication No. 2018/016369 is configured to adjust the misalignment of the first grid or the misalignment of the second grid in the following four directions. The four directions are the first orthogonal direction (first direction) of the X-ray irradiation axis direction, the rotation direction around the X-ray irradiation axis direction, and the in-plane direction orthogonal to the X-ray irradiation axis direction. The rotation direction (first rotation direction) and the rotation direction (second rotation direction) around the second orthogonal direction (second direction) orthogonal to the first orthogonal direction in the in-plane direction.

International Publication No. 2018/016369

Here, although not described in International Publication No. 2018/016369, in a conventional X-ray phase imaging apparatus such as International Publication No. 2018/016369, the first rotation direction and the second of the four directions are used. It is known that the misalignment of the grid (first grid or second grid) in the rotation direction has relatively little effect on the occurrence of unintended moire fringes. Therefore, the misalignment of the grids in the first rotation direction and the second rotation direction (parallelism between the first grid and the second grid in the in-plane direction orthogonal to the X-ray irradiation axis direction) can be determined, for example, before the device is shipped. If the grid is adjusted and fixed only once, unintended moire fringes are unlikely to occur even if the grid is slightly displaced in the first rotation direction and the second rotation direction after the adjustment. In this case, when using the device, it is considered possible to omit the adjustment of the misalignment of the grid in the first rotation direction and the second rotation direction in order to suppress the occurrence of unintended moire fringes.

Therefore, unlike the case where the positional deviation of the grid in the first rotation direction and the second rotation direction is adjusted based on the moire fringes detected by the detection unit, the apparatus does not perform imaging for acquiring the moire fringes. A simple method for adjusting only once before shipping is desired.

The present invention has been made to solve the above problems, and one object of the present invention is parallelism in an in-plane direction orthogonal to the X-ray irradiation axis direction in an X-ray phase imaging apparatus. Is to provide a grid adjustment method capable of easily adjusting.

In order to achieve the above object, the method of adjusting the lattice in one aspect of the present invention is arranged between the X-ray source and the detection unit, and forms a self-image by the X-rays emitted from the X-ray source. The first lattice of the In a method of adjusting a grid used in an X-ray phase imaging device that generates a phase contrast image containing at least one of images, adjustment is performed from an adjustment light source arranged between the first grid and the second grid. A step of irradiating adjustment light toward either the first lattice or the second lattice through an opening arranged so that the relative position with the adjustment light source is fixed in the vicinity of the light source, and the first step. The first reflection adjustment light reflected by either one of the first lattice or the second lattice and the second reflection adjustment light reflected by either the first lattice or the second lattice of the first reflection adjustment light. The first rotation direction around the first direction of the in-plane direction orthogonal to the X-ray irradiation axis direction connecting the X-ray source and the detection unit, and the in-plane so that both pass through the opening. A step of adjusting the positional deviation between the first lattice and the second lattice in at least one of the second rotation directions around the second direction orthogonal to the first direction of the directions is provided.

In the method for adjusting the lattice according to one aspect of the present invention, as described above, the first reflection adjusting light and the first reflection adjusting light reflected by either the first lattice or the second lattice are the first. Of the in-plane direction orthogonal to the X-ray irradiation axis direction, so that the second reflection adjusting light reflected by either the lattice or the second lattice passes through the opening. (Rotation direction around the first direction) and second rotation direction (rotation direction around the second direction orthogonal to the first direction in the in-plane direction) Provide a step of adjustment. Here, when both the first reflection adjusting light and the second reflection adjusting light pass through the opening when viewed from the first direction, the first grid and the first grid are viewed from the first direction. The two grids are substantially parallel (that is, the positional deviation between the first grid and the second grid in the first rotation direction is suppressed). Further, when both the first reflection adjusting light and the second reflection adjusting light pass through the opening when viewed from the second direction, the first grid and the second grid are viewed from the second direction. The grids are substantially parallel (that is, the misalignment between the first grid and the second grid in the second rotation direction is suppressed). Therefore, the positional deviation between the first grid and the second grid in the first rotation direction and the second rotation direction is such that the first reflection adjustment light and the second reflection adjustment light both pass through the opening. By adjusting, it is possible to suppress the positional deviation between the first grid and the second grid in the first rotation direction and the second rotation direction. As a result, the state in which light has passed through the opening and the state in which light has not passed through can be easily discriminated visually or by a photodetector having a relatively simple configuration, so that the in-plane orthogonal to the X-ray irradiation axis direction can be easily distinguished. The parallelism in the direction can be easily adjusted. In addition, since the position shift of the grid is adjusted depending on whether or not the light has passed through the opening, it is not necessary to adjust the grid using a spirit level or a protractor, and imaging for acquiring moire fringes is performed. No need.

In the method for adjusting the grid according to the above one aspect, the adjusting light preferably includes a laser beam. Here, since the laser light has high directivity (it travels linearly with almost no spread), when the first grid and the second grid are misaligned, the first reflection adjustment light or the first 2 Reflection adjustment light does not pass through the opening. That is, light having low directivity may pass through the opening even if the first grid and the second grid are misaligned. Therefore, if the laser beam is used as described above, it is possible to prevent the first lattice and the second lattice from passing through the opening when the positions are misaligned, so that the first lattice can be accurately performed. The misalignment between the and the second grid can be adjusted.

In the method for adjusting the grid according to the above one aspect, preferably, the adjusting light includes visible light. With this configuration, the positional deviation between the first grid and the second grid can be adjusted while visually observing the positions of the first reflection adjusting light and the second reflection adjusting light. As a result, in-plane orthogonal to the X-ray irradiation axis direction without using an optical detector or the like for detecting light in a wavelength band other than visible light as in the case of using light in a wavelength band other than visible light. The parallelism in the direction can be adjusted more easily.

In the method of adjusting the grid according to the above one aspect, preferably, the opening includes a slit, and the slit extends in the first direction when the step of adjusting the positional deviation in the first rotation direction is performed. When it is arranged and the step of adjusting the positional deviation in the second rotation direction is performed, it is arranged so as to extend in the second direction. Here, when the step of adjusting the positional deviation between the first lattice and the second lattice in the first rotation direction is performed, the light for adjusting the first reflection and the light for adjusting the second reflection do not interfere with each other. It is necessary to adjust the misalignment so that the light for adjusting the first reflection and the light for adjusting the second reflection are deviated from each other in the first direction and both pass through the opening. Further, when the step of adjusting the positional deviation between the first lattice and the second lattice in the second rotation direction is performed, the light for adjusting the first reflection and the light for adjusting the second reflection do not interfere with each other. It is necessary to adjust the misalignment so that the light for adjusting the first reflection and the light for adjusting the second reflection are deviated from each other in the second direction and both pass through the opening. Therefore, according to the above configuration, when the step of adjusting the positional deviation in the first rotation direction is performed, the first reflection adjusting light and the second reflection adjusting light are displaced from each other in the first direction. In the state, the positional deviation between the first lattice and the second lattice in the first rotation direction can be adjusted so that both of them pass through the slits arranged so as to extend in the first direction. Further, when the step of adjusting the positional deviation in the second rotation direction is performed, the first reflection adjusting light and the second reflection adjusting light are both displaced in the second direction in the second direction. The positional deviation between the first grid and the second grid in the second rotation direction can be adjusted so that the light passes through the slits arranged so as to extend to.

In this case, preferably, the step of irradiating the adjusting light is in the first direction with respect to the light incident surface of the member on which the slit is formed, when the step of adjusting the positional deviation in the first rotation direction is performed. When the step of irradiating the adjusting light in the inclined direction and the step of adjusting the positional deviation in the second rotation direction are performed, the member is inclined in the second direction with respect to the light incident surface of the member having the slit formed therein. The step of irradiating the adjusting light in the desired direction is included. With this configuration, when the step of adjusting the positional deviation in the first rotation direction is performed, the adjustment light is inclined in the first direction with respect to the light incident surface of the member on which the slit is formed. Therefore, the first reflection adjusting light and the second reflection adjusting light can be incident on the member in which the slit is formed in a state of being deviated from each other in the first direction. As a result, when the step of adjusting the positional deviation in the first rotation direction is performed, the first reflection adjusting light and the second reflection adjusting light are surely deviated from each other in the first direction. It can be in a state of passing through a slit arranged so as to extend in the first direction. Further, when the step of adjusting the positional deviation in the second rotation direction is performed, the light incident surface of the member on which the slit is formed is irradiated with the adjustment light in the direction inclined in the second direction. The light for adjusting the first reflection and the light for adjusting the second reflection can be surely incident on the member in which the slit is formed in a state of being displaced from each other in the second direction. As a result, when the step of adjusting the positional deviation in the second rotation direction is performed, the first reflection adjusting light and the second reflection adjusting light are surely deviated from each other in the second direction, and both are used. It can be made to pass through a slit arranged so as to extend in the second direction.

In the method of adjusting the grid according to the above one aspect, preferably, the step of adjusting the misalignment is performed with either the first grid or the second grid so that the light for adjusting the first reflection passes through the opening. After performing the step of adjusting the misalignment with the opening and the step of adjusting the misalignment so that the first reflection adjusting light passes through the opening, the second reflection adjusting light passes through the opening. As such, the step of adjusting the misalignment between either the first grid or the second grid and one of the first grid or the second grid is included. With this configuration, by performing the step of adjusting the positional deviation between either the first grid or the second grid and the opening, the light for adjusting the first reflection is brought into a state of passing through the opening. After that, by performing a step of adjusting the positional deviation between either the first grid or the second grid and either the first grid or the second grid, the light for adjusting the first reflection and the light for adjusting the first reflection are surely performed. The second reflection adjusting light can both pass through the opening.

In the method of adjusting the lattice according to the above one aspect, preferably, in the step of adjusting the misalignment, the second rotation is performed so that both the first reflection adjusting light and the second reflection adjusting light pass through the opening. After performing the step of adjusting the misalignment between the first grid and the second grid in the direction and the step of adjusting the misalignment of the first grid and the second grid in the second rotation direction, the light source for adjustment and the aperture. With the first lattice in the first rotation direction so that the first reflection adjustment light and the second reflection adjustment light both pass through the opening in a state where the portion is rotated approximately 90 degrees in the direction of the irradiation axis. The step of adjusting the misalignment with the second lattice is included. With this configuration, a step of adjusting the misalignment between the first grid and the second grid in the first rotation direction and a step of adjusting the misalignment of the first grid and the second grid in the second rotation direction. Can be done simply by changing the orientation of the adjusting light source and the opening between the substantially first direction and the substantially second direction. As a result, the misalignment in both the first rotation direction and the second rotation direction can be adjusted by the common adjustment light source and the opening, so that the configuration for adjusting the misalignment can be simplified. ..

In the method of adjusting the grid according to the above one aspect, preferably, in the step of irradiating the adjusting light and the step of adjusting the misalignment, the opening is formed between the first grid and the second grid in the irradiation axis direction. It is located in the center. Here, when the distance between the opening and the grid (first grid or second grid) is relatively short, the reflected light (first reflection adjustment) even if the first grid and the second grid are misaligned. The light for adjusting the second reflection or the light for adjusting the second reflection) may pass through the opening. Therefore, with the above configuration, the distance between the first reflection adjustment light and the opening and the distance between the second reflection adjustment light and the opening are relatively large, so that the first lattice and the second lattice can be used. When the position of the light is misaligned, the reflected light (light for adjusting the first reflection or light for adjusting the second reflection) passes through the opening, so that the first lattice and the second lattice are separated from each other. It is possible to prevent the misalignment from being unable to be adjusted appropriately.

In the method of adjusting the lattice according to the above one aspect, preferably, the step of adjusting the misalignment is generated by being diffracted by the lattice pattern when the lattice pattern is formed on the surface on which the adjusting light is reflected. In addition to including the step of adjusting the positional deviation using the first reflection adjusting light having the highest intensity in the plurality of first reflection adjusting lights, a lattice pattern is formed on the surface on which the first reflection adjusting light is reflected. If this is the case, the step of adjusting the misalignment using the second reflection adjusting light having the highest intensity in the plurality of second reflection adjusting lights generated by being diffracted by the lattice pattern is included. With this configuration, a plurality of first reflection adjusting light and second reflection adjusting light are formed by the lattice patterns formed on the surface on which the adjusting light is reflected and the surface on which the first reflection adjusting light is reflected, respectively. Even when the light is generated, the misalignment between the first lattice and the second lattice can be easily adjusted by using the first reflection adjustment light and the second reflection adjustment light having the highest intensity (sharpness). can do.

In the method of adjusting the lattice according to the above one aspect, preferably, in the step of adjusting the misalignment, the first reflection adjusting light, the second reflection adjusting light, and the second reflection adjusting light are the first lattice and the first light. It further includes a step of adjusting the misalignment based on the third reflection adjusting light reflected multiple times by the two lattices. With this configuration, the misalignment can be adjusted so that the multiple-reflected third reflection adjusting light passes through the opening, so that only the first reflection adjusting light and the second reflection adjusting light are used. Compared with the case where the misalignment is adjusted based on the above, the misalignment between the first lattice and the second lattice can be adjusted more precisely.

In the method of adjusting the grid according to the above one aspect, the width of the opening is preferably set to be equal to or larger than the spot diameter of the adjusting light. With this configuration, it is possible to prevent the adjustment light emitted from the adjustment light source from being blocked by a portion other than the opening of the member in which the opening is formed. As a result, the intensity of the first reflection adjusting light and the second reflection adjusting light is suppressed from becoming small (darkening), so that the first reflection adjusting light and the second reflection adjusting light pass through the opening. It can be easily determined whether or not it has been done.

According to the present invention, as described above, in the X-ray phase imaging apparatus, the parallelism in the in-plane direction orthogonal to the X-ray irradiation axis direction can be easily adjusted.

It is a figure which showed the whole structure of the X-ray phase imaging apparatus which uses the grid adjustment method by one Embodiment of this invention. It is a figure for demonstrating the grid position adjustment mechanism of the X-ray phase imaging apparatus which uses the grid adjustment method by one Embodiment of this invention. It is a figure for demonstrating the adjustment method of the lattice by one Embodiment of this invention. It is a figure for demonstrating the procedure of the lattice adjustment method by one Embodiment of this invention. It is a figure for demonstrating the relationship between the spot diameter of the adjustment light source, and the width of a slit. The orientation of the slit in the step of adjusting the misalignment between the first grid and the second grid in the second rotation direction, and the slit in the step of adjusting the misalignment of the first grid and the second grid in the first rotation direction. It is a figure for demonstrating the orientation. It is a figure for demonstrating the procedure of the lattice adjustment method by the 1st modification of one Embodiment of this invention. It is a figure for demonstrating the opening by the 2nd modification of one Embodiment of this invention. It is a figure for demonstrating the adjustment method of the lattice by the 3rd modification of one Embodiment of this invention. It is a figure for demonstrating the adjustment method of the lattice by the 4th modification of one Embodiment of this invention.

Hereinafter, embodiments embodying the present invention will be described with reference to the drawings.

First, with reference to FIGS. 1 and 2, the configuration of the X-ray phase imaging apparatus 100 in which the method for adjusting the grid G according to the embodiment of the present invention is used will be described.

As shown in FIG. 1, the X-ray phase imaging apparatus 100 includes a plurality of grids G including an X-ray tube 11, a detection unit 12, a first grid G1, a second grid G2, and a third grid G3. A processing unit 13 and a grid position adjusting mechanism 14 are provided. The X-ray tube 11 is an example of an "X-ray source" within the scope of claims.

In the X-ray phase imaging apparatus 100, the X-ray tube 11, the third grid G3, the first grid G1, the second grid G2, and the detection unit 12 connect the X-ray tube 11 and the detection unit 12. The lines are arranged side by side in this order in the irradiation axis direction (optical axis direction, Z direction). In the present specification, the direction from the X-ray tube 11 toward the detection unit 12 is the Z2 direction, and the opposite direction is the Z1 direction. Further, the direction in which the grids of the plurality of grids G in the in-plane direction orthogonal to the Z direction extend is defined as the X direction. Further, the direction (direction orthogonal to the Z direction and the X direction) of each of the plurality of grids G among the in-plane directions orthogonal to the Z direction is defined as the Y direction. The X direction and the Y direction are examples of the "first direction" and the "second direction" of the claims, respectively.

The X-ray tube 11 is an X-ray generator capable of generating X-rays by applying a high voltage. The X-ray tube 11 is configured to irradiate the generated X-rays in the Z2 direction.

The detection unit 12 detects the X-rays emitted from the X-ray tube 11 and converts the detected X-rays into an electric signal. The detection unit 12 is, for example, an FPD (Flat Panel Detector). The detection unit 12 is composed of a plurality of conversion elements (not shown) and pixel electrodes (not shown) arranged on the plurality of conversion elements. The plurality of conversion elements and pixel electrodes are arranged side by side in the X direction and the Y direction at a predetermined period (pixel pitch). The detection signal (electric signal) converted by the detection unit 12 is sent to the image processing unit 13b (described later) included in the processing unit 13.

The first lattice G1 has a lattice pattern (a plurality of slits G1a and an X-ray phase changing portion G1b) arranged in a predetermined period (lattice pitch) d1 in the Y direction. In the first grid G1, the grid pattern is provided on the X-ray tube 11 side (Z1 side) of the first grid G1. Each slit G1a and the X-ray phase changing portion G1b are formed so as to extend linearly in the X direction. The first grid G1 is a so-called phase grid. The first grid G1 is arranged between the X-ray tube 11 and the second grid G2, and is provided to form a self-image (by the Talbot effect) by the X-rays emitted from the X-ray tube 11. There is. In the Talbot effect, when X-rays having coherence pass through the first lattice G1 in which the slit G1a is formed, the first lattice G1 is located at a predetermined distance (Talbot distance) from the first lattice G1. It means that the image (self-image) of is formed.

The second lattice G2 has a lattice pattern (a plurality of X-ray transmitting portions G2a and an X-ray absorbing portion G2b) arranged in a predetermined period (lattice pitch) d2 in the Y direction. In the second grid G2, the grid pattern is provided on the X-ray tube 11 side (Z1 side) of the second grid G2. Each of the X-ray transmitting portion G2a and the X-ray absorbing portion G2b is formed so as to extend linearly in the X direction. The second grid G2 is a so-called absorption grid. The second lattice G2 is arranged between the first lattice G1 and the detection unit 12, and is configured to interfere with the self-image formed by the first lattice G1. The second lattice G2 is arranged at a position separated from the first lattice G1 by a Talbot distance in order to interfere with the self-image and the second lattice G2. That is, in the X-ray phase imaging apparatus 100, the interference fringes (moire fringes) generated by the interference between the self-image and the second lattice G2 are detected by the detection unit 12 as X-rays.

The third lattice G3 has a plurality of slits G3a and an X-ray absorbing portion G3b arranged at a predetermined period (pitch) d3. Each of the slits G3a and the X-ray absorbing portion G3b is formed so as to extend linearly in the X direction. The third lattice G3 is arranged between the X-ray tube 11 and the first lattice G1, and X-rays are emitted from the X-ray tube 11. The third lattice G3 is configured to use X-rays that have passed through each slit G3a as a line light source corresponding to the position of each slit G3a. That is, the third lattice G3 is provided to enhance the coherence of X-rays emitted from the X-ray tube 11.

The processing unit 13 includes a control unit 13a and an image processing unit 13b.

The control unit 13a is configured to control the operation of the grid position adjusting mechanism 14. The control unit 13a includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like.

The image processing unit 13b is configured to generate an image such as a phase contrast image based on the detection signal sent from the detection unit 12. The image processing unit 13b includes, for example, a processor such as a GPU (Graphics Processing Unit) or an FPGA (Field-Programmable Gate Array) configured for image processing.

The phase contrast image includes at least one of an absorption image, a phase differential image and a dark field image. The absorption image is an X-ray image imaged based on the difference in the degree of absorption of X-rays. The phase differential image is an X-ray image imaged based on the phase shift of the X-ray. The dark-field image is a Visibility image obtained by a change in Visibility based on small-angle scattering of an object. The dark field image is also called a small-angle scattered image. "Visibility" means sharpness.

The grid position adjusting mechanism 14 is provided in the first grid G1 and the second grid G2, respectively. As shown in FIG. 2, the grid position adjusting mechanism 14 rotates the grid G in the X direction, the Y direction, the Z direction, the rotation direction Rz in the Z direction, the rotation direction Rx in the X direction, and the rotation in the Y direction. It is configured to be movable in the direction Ry. The lattice position adjusting mechanism 14 includes an X-direction linear motion mechanism 14a, a Z-direction linear motion mechanism 14b, a Y-direction linear motion mechanism 14c, a linear motion mechanism connection portion 14d, a stage support unit drive unit 14e, and a stage support unit. 14f, a stage drive unit 14g, and a stage 14h are included. The rotation direction Rx and the rotation direction Ry are examples of the "first rotation direction" and the "second rotation direction" in the claims, respectively.

The X-direction linear motion mechanism 14a, the Z-direction linear motion mechanism 14b, and the Y-direction linear motion mechanism 14c are configured to be movable in the X-direction, the Z-direction, and the Y-direction, respectively. The X-direction linear motion mechanism 14a, the Z-direction linear motion mechanism 14b, and the Y-direction linear motion mechanism 14c include, for example, a stepping motor and the like. The grid position adjusting mechanism 14 causes the grid G to move in the X, Z, and Y directions by the operation of the X-direction linear motion mechanism 14a, the Z-direction linear motion mechanism 14b, and the Y-direction linear motion mechanism 14c, respectively. It is configured.

The stage support portion 14f supports the stage 14h for placing (or holding) the lattice G from the Z2 direction. The stage drive unit 14g is configured to reciprocate the stage 14h in the X direction. The bottom of the stage 14h is formed in a convex curved surface toward the stage support portion 14f, and is configured to rotate in the rotation direction Ry by being reciprocated in the X direction. Further, the stage support unit drive unit 14e is configured to reciprocate the stage support unit 14f in the Y direction. Further, the linear motion mechanism connecting portion 14d is provided in the X-direction linear motion mechanism 14a so as to be rotatable in the rotation direction Rz. Further, the bottom of the stage support portion 14f is formed in a convex curved surface shape toward the linear motion mechanism connecting portion 14d, and is configured to rotate in the rotation direction Rx by being reciprocated in the Y direction. .. The grid position adjusting mechanism 14 may have a mechanism for holding the grid G, such as a chuck mechanism or a hand mechanism.

(Adjustment method of misalignment between the first grid and the second grid)
Next, a method of adjusting the grid G (a method of adjusting the positional deviation between the first grid G1 and the second grid G2) will be described with reference to FIGS. 3 to 6.

As shown in FIG. 3, in the present embodiment, the adjustment method of the grid G is from the adjustment light source 21 arranged between the first grid G1 and the second grid G2 to the vicinity of the adjustment light source 21. A step of irradiating the adjustment light L toward the second lattice G2 through the slit 22a arranged so that the relative position with respect to the light source 21 is fixed is provided. Further, the method of adjusting the grid G is as follows: a first reflection adjusting light L1 reflected by the second grid G2 and a second reflection adjusting light L2 in which the first reflection adjusting light L1 is reflected by the first grid G1. However, a step of adjusting the positional deviation between the first lattice G1 and the second lattice G2 in the rotation direction Rx and the rotation direction Ry is provided so that both of them pass through the slit 22a. The slit 22a is an example of an "opening" in the claims.

Specifically, the slit 22a is arranged so as to extend in the X direction when the step of adjusting the positional deviation in the rotation direction Rx is performed. Then, in the step of irradiating the adjusting light L, when the step of adjusting the positional deviation in the rotation direction Rx is performed, the shielding member 22 in which the slit 22a is formed is inclined in the X direction with respect to the light incident surface 22b. The step of irradiating the adjusting light L in the desired direction is included. Further, the slit 22a is arranged so as to extend in the Y direction when the step of adjusting the positional deviation in the rotation direction Ry is performed. Then, in the step of irradiating the adjusting light L, when the step of adjusting the positional deviation in the rotation direction Ry is performed, the direction inclined in the Y direction with respect to the light incident surface 22b of the member on which the slit 22a is formed. Includes a step of irradiating the adjustment light L. The shielding member 22 is an example of a “member having a slit” within the scope of the claims.

Further, as shown in FIG. 4, the step of adjusting the misalignment is a step of adjusting the misalignment between the second lattice G2 and the slit 22a so that the first reflection adjusting light L1 passes through the slit 22a. include. Further, in the step of adjusting the misalignment, the second reflection adjusting light L2 passes through the slit 22a after the step of adjusting the misalignment so that the first reflection adjusting light L1 passes through the slit 22a. As described above, the step of adjusting the positional deviation between the first lattice G1 and the second lattice G2 is included.

Further, in the step of adjusting the misalignment, the first grid G1 and the second grid in the rotation direction Ry so that the first reflection adjusting light L1 and the second reflection adjusting light L2 both pass through the slit 22a. The step of adjusting the misalignment with G2 is included. Further, as shown in FIG. 6, in the step of adjusting the misalignment, after performing the step of adjusting the misalignment between the first grid G1 and the second grid G2 in the rotation direction Ry, the adjusting light source 21 and the slit 22a With the first grid G1 in the rotation direction Rx so that the first reflection adjusting light L1 and the second reflection adjusting light L2 both pass through the slit 22a in a state of being rotated approximately 90 degrees in the Z direction. The step of adjusting the misalignment with the second lattice G2 is included.

Specifically, as shown in FIG. 3, first, an adjustment unit 20 for adjusting the misalignment between the first grid G1 and the second grid G2 is provided between the first grid G1 and the second grid G2. Be placed. The adjustment unit 20 includes an adjustment light source 21 and a shielding member 22. The adjustment light source 21 is configured to be able to irradiate the adjustment light L. The adjustment light L is a laser light and visible light. For example, the adjustment light source 21 is a laser pointer. The laser diameter is, for example, 5 mm or less. The shielding member 22 has a slit 22a formed in the center thereof. As shown in FIG. 6, the width W2 of the slit 22a is set to be equal to or larger than the spot diameter W1 of the adjusting light L. The shielding member 22 is made of, for example, an opaque plate.

As shown in FIG. 3, in the adjustment unit 20, the relative positions of the adjustment light source 21 and the shielding member 22 are fixed so that the adjustment light L emitted from the adjustment light source 21 passes through the slit 22a. .. Further, the relative positions of the adjusting light source 21 and the shielding member 22 are fixed so that the adjusting light L is inclined and incident on the light incident surface 22b at an inclination angle α. In the present embodiment, the adjusting unit 20 (adjusting light source 21 and slit 22a) has the first grid G1 and the second grid G2 in the step of irradiating the adjusting light L and the step of adjusting the misalignment. It is placed in the center of the space.

In the step of adjusting the positional deviation between the first lattice G1 and the second lattice G2 in the rotation direction Ry, first, the adjusting unit 20 adjusts the light incident surface 22b of the shielding member 22 on which the slit 22a is formed so as to face the Z direction. Be placed. That is, the adjustment unit 20 is arranged so that the slit 22a extends in the substantially Y direction. In this state, the adjusting light L irradiated by the adjusting light source 21 travels in a direction inclined at an inclination angle α with respect to a direction (Z direction) orthogonal to the light incident surface 22b when viewed from the X direction. Note that the example of FIG. 3 shows an example in which the adjustment light L (L0) emitted from the adjustment light source 21 is emitted in a direction inclined at an inclination angle α toward the Z1 side with respect to the Z direction.

In the step of adjusting the positional deviation between the first grid G1 and the second grid G2 in the rotation direction Ry, the adjustment light L0 is applied to the Z2 side. That is, the adjusting light L0 is incident on the surface G2c (see FIG. 1) of the second lattice G2 on the X-ray tube 11 side (Z1 side) in a direction inclined toward the Z2 side with respect to the Z direction when viewed from the X direction. Therefore, the first reflection adjusting light L1 reflected by the second lattice G2 is reflected in a direction inclined toward the Z1 side with respect to the Z direction. Then, the first reflection adjusting light L1 is inclined toward the Z1 side with respect to the Z direction with respect to the surface G1d (see FIG. 1) on the detection unit 12 side (Z2 side) of the first lattice G1 when viewed from the X direction. The second reflection adjusting light L2 reflected by the first lattice G1 is reflected in a direction inclined toward the Z2 side with respect to the Z direction. In FIG. 3, the misalignment between the first grid G1 and the second grid G2 in the rotation direction Ry is suppressed, and the first reflection adjusting light L1 and the second reflection adjusting light L2 pass through the slit 22a. Indicates the state.

Here, in the X-ray phase imaging apparatus 100, the surface G1d on the detection unit 12 side (Z2 side) of the first lattice G1 and the surface G2c on the X-ray tube 11 side (Z1 side) of the second lattice G2 are lasers. It is made of a material that easily reflects light. When the surfaces G1d and G2c are made of a material that does not easily reflect the laser beam, Al or the like may be thinly vapor-deposited in advance.

Further, as described above, in the X-ray phase imaging apparatus 100, a grid pattern is formed on the X-ray tube 11 side (Z1 side) of the second grid G2. That is, a lattice pattern is formed on the surface G2c on the X-ray tube 11 side (Z1 side) of the second lattice G2 on which the first reflection adjusting light L1 is reflected. When light is incident on the surface G2c on which the lattice pattern is formed, the light is diffracted by the lattice pattern to generate a plurality of lights. Since the lattice pattern is not formed on the detection unit 12 side (Z2 side) of the second lattice G2, the light L2 for adjusting the second reflection does not diffract the light due to the lattice pattern.

Therefore, in the present embodiment, the step of adjusting the misalignment is the first reflection adjusting light L1 having the highest intensity among the plurality of first reflection adjusting lights L1 generated by being diffracted by the second lattice G2. Includes the step of adjusting the misalignment using. The first reflection adjusting light L1 having the highest intensity is the first reflection adjusting light L1 (so-called 0th-order diffracted light) having a reflection angle equal to the incident angle of the adjusting light L0. In the drawing, only the 0th-order diffracted light of the first reflection adjusting light L1 is shown.

As shown in FIG. 4A, before adjusting the positional deviation between the first grid G1 and the second grid G2 in the rotation direction Ry, the first grid G1 and the second grid G2 are viewed from the Y direction. It is in a non-parallel state. Further, the shielding member 22 arranged between the first lattice G1 and the second lattice G2 and the first lattice G1 and the second lattice G2 are in a non-parallel state when viewed from the Y direction. That is, the adjusting light L0 is inclined in a direction orthogonal to the surface G2c (see FIG. 1) of the second lattice G2 on the X-ray tube 11 side (Z1 side) when viewed from the Y direction. The first reflection adjusting light L1 is reflected in a direction different from the direction in which the adjusting light L0 is incident. Therefore, the first reflection adjusting light L1 does not pass through the slit 22a and is blocked by the portion of the shielding member 22 where the slit 22a is not formed.

Therefore, as shown in FIG. 4B, the shielding member 22 (adjusting unit 20) is angled Ry in the rotation direction Ry so that the shielding member 22 and the second lattice G2 are substantially parallel when viewed from the Y direction. Rotate only (S). As a result, the shielding member 22 and the second lattice G2 are in a substantially parallel state when viewed from the Y direction, so that the first reflection adjusting light L1 is reflected in substantially the same direction as the direction in which the adjusting light L0 is incident. Will be done. Therefore, the first reflection adjusting light L1 passes through the slit 22a and is incident on the detection unit 12 side (Z2 side) of the first lattice G1. The rotation of the adjustment unit 20 is performed while visually observing the first reflection adjustment light L1 so that the first reflection adjustment light L1 passes through the slit 22a. Further, the rotation of the adjustment unit 20 and the rotation of the first grid G1 described later are performed by the user operating the grid position adjusting mechanism 14. As a result, unlike the case where the control unit 13a or the like confidently determines and operates the grid position adjustment mechanism 14 so that the first reflection adjustment light L1 passes through the slit 22a, the load of the control unit 13a is applied. Can be reduced.

By the above step (the step of rotating the adjusting unit 20 so that the first reflection adjusting light L1 passes through the slit 22a), the shielding member 22 and the second lattice G2 are in a substantially parallel state. , The first lattice G1 and the shielding member 22 and the second lattice G2 are in a non-parallel state when viewed from the Y direction. That is, the first reflection adjusting light L1 is inclined and incident in a direction orthogonal to the surface G1d (see FIG. 1) on the detection unit 12 side (Z2 side) of the first lattice G1 when viewed from the Y direction. Therefore, the second reflection adjusting light L2 is reflected in a direction different from the direction in which the first reflection adjusting light L1 is incident. Therefore, the second reflection adjusting light L2 does not pass through the slit 22a and is blocked by the portion of the shielding member 22 where the slit 22a is not formed.

Therefore, as shown in FIG. 4C, the angle of the first lattice G1 in the rotation direction Ry is such that the first lattice G1 is substantially parallel to the shielding member 22 and the second lattice G2 when viewed from the Y direction. Rotate only Ry (G1). As a result, the first lattice G1 and the shielding member 22 and the second lattice G2 are in a substantially parallel state when viewed from the Y direction. Therefore, the first reflection adjusting light L1 is incident on the second reflection adjusting light L2. It is reflected in almost the same direction as the light. Therefore, the second reflection adjusting light L2 passes through the slit 22a and is incident on the X-ray tube 11 side (Z1 side) of the second lattice G2. The rotation of the first lattice G1 is performed while visually observing the second reflection adjusting light L2 so that the second reflection adjusting light L2 passes through the slit 22a.

The above steps (a step of rotating the adjustment unit 20 so that the first reflection adjusting light L1 passes through the slit 22a, and a state in which the second reflection adjusting light L2 passes through the slit 22a. By the step of rotating the first lattice G1), the first reflection adjusting light L1 and the second reflection adjusting light L2 both pass through the slit 22a when viewed from the Y direction. Adjust the misalignment between G1 and the second lattice G2. As a result, the first grid G1 and the second grid G2 are substantially parallel to each other when viewed from the Y direction (that is, the positional deviation between the first grid G1 and the second grid G2 in the rotation direction Ry is suppressed).

Next, as shown in FIG. 6, the adjustment unit 20 is rotated about 90 degrees in the Z direction. In this state, the same process as the adjustment of the positional deviation between the first lattice G1 and the second lattice G2 in the rotation direction Ry is also performed for the rotation direction Rx. That is, the positions of the first grid G1 and the second grid G2 so that the first reflection adjusting light L1 and the second reflection adjusting light L2 both pass through the slit 22a when viewed from the X direction. Adjust the deviation. As a result, the first grid G1 and the second grid G2 are substantially parallel to each other when viewed from the X direction (that is, the positional deviation between the first grid G1 and the second grid G2 in the rotation direction Rx is suppressed). As described above, the positional deviation between the first lattice G1 and the second lattice G2 in the rotation direction Rx and the rotation direction Ry is suppressed, and the occurrence of unintended moire fringes is suppressed.

(Effect of embodiment)
In this embodiment, the following effects can be obtained.

In the present embodiment, as described above, in the method of adjusting the grid G, the first reflection adjusting light L1 reflected by the second grid G2 and the first reflection adjusting light L1 are reflected by the first grid G1. A step of adjusting the positional deviation between the first lattice G1 and the second lattice G2 in the rotation direction Rx and the rotation direction Ry is provided so that the second reflection adjusting light L2 both passes through the slit 22a. As a result, the first grid G1 and the second grid G2 in the rotation direction Rx and the rotation direction Ry are arranged so that the first reflection adjustment light L1 and the second reflection adjustment light L2 both pass through the slit 22a. By adjusting the misalignment of, it is possible to suppress the misalignment between the first grid G1 and the second grid G2 in the rotation direction Rx and the rotation direction Ry. As a result, the state in which the light has passed through the slit 22a and the state in which the light has not passed through can be easily visually distinguished, so that the parallelism in the in-plane direction orthogonal to the X-ray irradiation axis direction (Z direction) can be simplified. Can be adjusted to. Further, since the positional deviation of the grid G is adjusted depending on whether or not the light has passed through the slit 22a, it is not necessary to adjust the grid G using a spirit level or an angle meter, and imaging for acquiring moire fringes is necessary. There is no need to do.

Further, in the present embodiment, as described above, the adjustment light L is a laser light. As a result, if a laser beam having high directivity is used, it is possible to prevent the first lattice G1 and the second lattice G2 from passing through the slit 22a when they are misaligned, so that the accuracy is high. , The misalignment between the first grid G1 and the second grid G2 can be adjusted.

Further, in the present embodiment, as described above, the adjusting light L is defined as visible light. Thereby, the positional deviation between the first lattice G1 and the second lattice G2 can be adjusted while visually observing the positions of the first reflection adjusting light L1 and the second reflection adjusting light L2. As a result, the X-ray irradiation axis direction (Z direction) and the X-ray irradiation axis direction (Z direction) can be obtained without using an optical detector or the like for detecting light in a wavelength band other than visible light as in the case of using light in a wavelength band other than visible light. The parallelism in the orthogonal in-plane direction can be adjusted more easily.

Further, in the present embodiment, as described above, when the step of adjusting the positional deviation in the rotation direction Rx is performed, the slits 22a are arranged so as to extend in the X direction to adjust the positional deviation in the rotation direction Ry. When the step is performed, it is arranged so as to extend in the Y direction. As a result, when the step of adjusting the positional deviation in the rotation direction Rx is performed, the first reflection adjusting light L1 and the second reflection adjusting light L2 are both displaced in the X direction in the X direction. The positional deviation between the first lattice G1 and the second lattice G2 in the rotation direction Rx can be adjusted so as to pass through the slits 22a arranged so as to extend to. Further, when the step of adjusting the positional deviation in the rotation direction Ry is performed, the first reflection adjusting light L1 and the second reflection adjusting light L2 are both displaced in the Y direction in the Y direction. The positional deviation between the first lattice G1 and the second lattice G2 in the rotation direction Ry can be adjusted so as to pass through the slits 22a arranged so as to extend.

Further, in the present embodiment, as described above, in the step of irradiating the adjusting light L, when the step of adjusting the positional deviation in the rotation direction Rx is performed, the light of the shielding member 22 on which the slit 22a is formed is formed. When the step of irradiating the adjusting light L in the direction inclined in the X direction with respect to the incident surface 22b and the step of adjusting the positional deviation in the rotation direction Ry is performed, the shielding member 22 in which the slit 22a is formed is formed. The step of irradiating the adjusting light L in a direction inclined in the Y direction with respect to the light incident surface 22b of the above is included. As a result, when the step of adjusting the positional deviation in the rotation direction Rx is performed, the adjusting light L is provided in a direction inclined in the X direction with respect to the light incident surface 22b of the shielding member 22 on which the slit 22a is formed. Since the light is irradiated, the first reflection adjusting light L1 and the second reflection adjusting light L2 can be incident on the shielding member 22 in which the slit 22a is formed in a state of being displaced from each other in the X direction. As a result, when the step of adjusting the positional deviation in the rotation direction Rx is performed, the first reflection adjusting light L1 and the second reflection adjusting light L2 are surely deviated from each other in the X direction. It can be made to pass through the slit 22a arranged so as to extend in the X direction. Further, when the step of adjusting the positional deviation in the rotation direction Ry is performed, the light incident surface 22b of the shielding member 22 on which the slit 22a is formed is irradiated with the adjusting light L in a direction inclined in the Y direction. Therefore, the first reflection adjusting light L1 and the second reflection adjusting light L2 can be surely incident on the shielding member 22 in which the slit 22a is formed in a state of being displaced from each other in the Y direction. As a result, when the step of adjusting the positional deviation in the rotation direction Ry is performed, the first reflection adjusting light L1 and the second reflection adjusting light L2 are surely deviated from each other in the Y direction. It can be made to pass through the slit 22a arranged so as to extend in the Y direction.

Further, in the present embodiment, as described above, in the step of adjusting the misalignment, the misalignment between the second lattice G2 and the slit 22a is adjusted so that the first reflection adjusting light L1 passes through the slit 22a. After performing the step of adjusting the misalignment so that the first reflection adjusting light L1 passes through the slit 22a, the first lattice so that the second reflection adjusting light L2 passes through the slit 22a. The step of adjusting the misalignment between G1 and the second lattice G2 is included. As a result, by performing the step of adjusting the positional deviation between the second lattice G2 and the slit 22a, the first reflection adjusting light L1 is brought into a state of passing through the slit 22a, and then the first lattice G1 and the second lattice are used. By performing the step of adjusting the positional deviation from G2, it is possible to ensure that both the first reflection adjusting light L1 and the second reflection adjusting light L2 pass through the slit 22a.

Further, in the present embodiment, as described above, in the step of adjusting the misalignment, the rotation direction Ry is such that the first reflection adjusting light L1 and the second reflection adjusting light L2 both pass through the slit 22a. After performing the step of adjusting the positional deviation between the first lattice G1 and the second lattice G2 and the step of adjusting the positional deviation between the first lattice G1 and the second lattice G2 in the rotation direction Ry, the light source for adjustment is performed. With the 21 and the slit 22a rotated approximately 90 degrees in the X-ray irradiation axis direction (Z direction), the first reflection adjusting light L1 and the second reflection adjusting light L2 both pass through the slit 22a. Including a step of adjusting the positional deviation between the first lattice G1 and the second lattice G2 in the rotation direction Rx. As a result, the step of adjusting the misalignment between the first grid G1 and the second grid G2 in the rotation direction Rx and the step of adjusting the misalignment of the first grid G1 and the second grid G2 in the rotation direction Ry can be performed. It can be performed only by changing the directions of the adjusting light source 21 and the slit 22a between the substantially X direction and the substantially Y direction. As a result, the misalignment in both the rotation direction Rx and the rotation direction Ry can be adjusted by the common adjustment light source 21 and the slit 22a, so that the configuration for adjusting the misalignment can be simplified.

Further, in the present embodiment, as described above, in the step of irradiating the adjusting light L and the step of adjusting the positional deviation, the slits 22a are formed into the first grid G1 and the second grid in the irradiation axis direction (Z direction). It is placed in the central part between G2. As a result, the distance between the first reflection adjusting light L1 and the slit 22a and the distance between the second reflection adjusting light L2 and the slit 22a become relatively large, so that the first lattice G1 and the second lattice G2 are misaligned. In this case, the reflected light (first reflection adjusting light L1 or second reflection adjusting light L2) passes through the slit 22a, so that the first lattice G1 and the second lattice G2 It is possible to prevent the misalignment of the light from being unable to be adjusted appropriately.

Further, in the present embodiment, as described above, in the step of adjusting the positional deviation, a lattice pattern is formed on the surface G2c on which the first reflection adjustment light L1 is reflected, and the light is diffracted by the lattice pattern. In the generated first reflection adjusting light L1, the step of adjusting the positional deviation by using the first reflection adjusting light L1 having the highest intensity is included. As a result, even when a plurality of first reflection adjusting lights L1 are generated by the lattice pattern formed on the surface G2c on which the first reflection adjusting light L1 is reflected, the first reflection having the highest intensity (sharpness) is generated. By using the adjusting light L1, the positional deviation between the first lattice G1 and the second lattice G2 can be easily adjusted.

Further, in the present embodiment, as described above, the width W2 of the slit 22a is set so as to be equal to or larger than the spot diameter W1 of the adjusting light L. As a result, it is possible to prevent the adjusting light L emitted from the adjusting light source 21 from being blocked by a portion other than the slit 22a of the shielding member 22 in which the slit 22a is formed. As a result, the intensity of the first reflection adjusting light L1 and the second reflection adjusting light L2 is suppressed from becoming small (darkening), so that the first reflection adjusting light L1 and the second reflection adjusting light L2 become It can be easily determined whether or not the light has passed through the slit 22a.

[Modification example]
It should be noted that the embodiments disclosed this time are exemplary in all respects and are not considered to be restrictive. The scope of the present invention is shown by the scope of claims rather than the description of the above-described embodiment, and further includes all modifications (modifications) within the meaning and scope equivalent to the scope of claims.

For example, in the above embodiment, an example in which the adjusting light L is a laser light is shown, but the present invention is not limited to this. In the present invention, the adjusting light L may be configured to use a type of light other than the laser light. When a light source that emits light having no directivity is used, it is preferable to change the light having no directivity into light having directivity and irradiate it with a member for condensing the light. ..

Further, in the above embodiment, an example in which the adjusting light L is visible light is shown, but the present invention is not limited to this. In the present invention, the adjustment light L may be configured to use light in a wavelength band other than visible light. In that case, a photodetector or the like for detecting light in a wavelength band other than visible light may be used. In this case, the control unit may automatically rotate the adjustment unit 20 and the first grid G1 based on the detection result of the photodetector.

Further, in the above embodiment, an example is shown in which the shielding member 22 (adjusting unit 20) is rotated by an angle Ry (S) in the rotation direction Ry so that the shielding member 22 and the second lattice G2 are substantially parallel to each other. , The present invention is not limited to this. In the present invention, as in the first modification shown in FIG. 7, the second grid G2 is rotated by an angle Ry (G2) in the rotation direction Ry so that the shielding member 22 and the second grid G2 are substantially parallel to each other. It may be configured as follows.

Further, in the above embodiment, an example in which the first lattice G1 is rotated by an angle Ry (G1) in the rotation direction Ry so that the first lattice G1 and the shielding member 22 and the second lattice G2 are in a substantially parallel state. However, the present invention is not limited to this. In the present invention, the shielding member 22 and the second lattice G2 are rotated by a predetermined angle in the rotation direction Ry so that the first lattice G1 and the shielding member 22 and the second lattice G2 are in a substantially parallel state. It may be configured.

Further, in the above embodiment, an example in which one slit 22a is applied as the "opening" of the present invention is shown, but the present invention is not limited to this. In the present invention, a plurality of rectangular holes may be applied as the "opening" of the present invention, as in the shielding member 222 according to the modified example shown in FIG. In the example shown in FIG. 8, the shielding member 222 has an opening 222a in which a plurality of rectangular holes are arranged in a row.

Further, in the above embodiment, in the step of irradiating the adjusting light L and the step of adjusting the positional deviation, the slits 22a are arranged with the first grid G1 and the second grid G2 in the X-ray irradiation axis direction (Z direction). Although an example of arranging it in the central portion between the two is shown, the present invention is not limited to this. In the present invention, in the step of irradiating the adjusting light L and the step of adjusting the misalignment, the slit 22a is placed between the first grid G1 and the second grid G2 in the X-ray irradiation axis direction (Z direction). It may be configured to be arranged other than the central portion. In that case, it is preferable to arrange the slits 22a so that the first lattice G1 or the second lattice G2 and the slits 22a are not significantly close to each other. Further, a step of adjusting the positional deviation between the second lattice G2 and the slit 22a so that the first reflection adjusting light L1 passes through the slit 22a, and the second reflection adjusting light L2 passes through the slit 22a. As described above, in the step of adjusting the positional deviation between the first lattice G1 and the second lattice G2, the position of the slit 22a between the first lattice G1 and the second lattice G2 may be changed.

Further, in the above embodiment, the positional deviation between the first grid G1 and the second grid G2 is adjusted so that the first reflection adjusting light L1 and the second reflection adjusting light L2 both pass through the slit 22a. Although the example configured as described above is shown, the present invention is not limited to this. In the present invention, as in the third modification shown in FIG. 9, the first reflection adjusting light L1, the second reflection adjusting light L2, and the second reflection adjusting light L2 are the first lattice G1 and the second lattice. The positional deviation may be adjusted based on the third reflection adjusting light L3 that is multiplely reflected by G2. In FIG. 9, as the multiple-reflected third reflection adjusting light L3, the third reflection adjusting light L31 in which the second reflection adjusting light L2 is reflected by the second lattice G2 and the third reflection adjusting light L31 are shown. The third reflection adjusting light L32 reflected by the first lattice G1 is shown. As a result, the misalignment can be adjusted so that the multiple-reflected third reflection adjusting light L3 passes through the slit 22a. Therefore, it is based only on the first reflection adjusting light L1 and the second reflection adjusting light L2. Compared with the case of adjusting the misalignment, the misalignment between the first grid G1 and the second grid G2 can be adjusted more precisely.

Further, in the above embodiment, the first reflection adjusting light L1 reflected by the second grid G2 and the second reflection adjusting light L2 in which the first reflection adjusting light L1 is reflected by the first grid G1 are An example of adjusting the positional deviation between the first lattice G1 and the second lattice G2 so that both of them pass through the slit 22a has been shown, but the present invention is not limited to this. In the present invention, as in the fourth modification shown in FIG. 10, the first reflection adjusting light L1 reflected by the first grid G1 and the first reflection adjusting light L1 are reflected by the second grid G2. The positional deviation between the first lattice G1 and the second lattice G2 may be adjusted so that the two reflection adjusting light L2 both pass through the slit 22a.

Further, in the above embodiment, after adjusting the misalignment between the first grid G1 and the second grid G2 in the rotation direction Ry, the misalignment between the first grid G1 and the second grid G2 in the rotation direction Rx is adjusted. However, the present invention is not limited to this. In the present invention, after adjusting the misalignment between the first grid G1 and the second grid G2 in the rotation direction Rx, the misalignment between the first grid G1 and the second grid G2 in the rotation direction Ry is adjusted. You may. Further, it may be configured to adjust only the positional deviation between the first lattice G1 and the second lattice G2 in any one direction of the rotation direction Rx or the rotation direction Ry.

Further, in the above embodiment, an example is shown in which the grid G adjustment method is used for the X-ray phase imaging device 100 in which the grid pattern is provided on the X-ray tube 11 side (Z1 side) of the grid G. The present invention is not limited to this. In the present invention, the method for adjusting the grid G may be used for the X-ray phase imaging device 100 in which the grid pattern is provided on the detection unit 12 side (Z2 side) of the grid G.

Further, in the above embodiment, in the step of adjusting the positional deviation between the first lattice G1 and the second lattice G2 in the rotation direction Ry, an example in which the slit 22a is arranged so as to extend along the Y direction is shown. , The present invention is not limited to this. In the present invention, in the step of adjusting the positional deviation between the first lattice G1 and the second lattice G2 in the rotation direction Ry, the slits 22a may be arranged along a direction inclined with respect to the Y direction. In this case, it is necessary that the positions of the first grid G1 and the second grid G2 in the rotation direction Rx are aligned.

Further, in the above embodiment, the plurality of lattices G are arranged between the X-ray tube 11 and the first lattice G1, and the third lattice for enhancing the coherence of the X-rays emitted from the X-ray tube 11 Although an example configured to include G3 is shown, the present invention is not limited to this. In the present invention, it may be configured so as not to include the third lattice G3.

Further, in the above embodiment, an example in which the first lattice G1 is used as a phase lattice in order to form a self-image due to the Talbot effect is shown, but the present invention is not limited to this. In the present invention, since the self-image may be a striped pattern, an absorption grid may be used instead of the phase grid. When the absorption grid is used, a region where a striped pattern is simply generated (non-interferometer) and a region where a self-image is generated due to the Talbot effect (interferometer) are generated depending on optical conditions such as distance.

11 X-ray tube (X-ray source)
12 Detection unit 21 Adjustment light source 22 Shielding member (member with slits formed)
22a slit (opening)
22b Light incident surface (of the member in which the slit is formed) 100 X-ray phase imaging device G1 1st lattice G2 2nd lattice G3 3rd lattice L Adjustment light L1 1st reflection adjustment light L2 2nd reflection adjustment light L3 Third reflection adjustment light W1 (adjustment light) spot diameter W2 (opening) width

Claims (11)

A first lattice arranged between the X-ray source and the detection unit for forming a self-image by X-rays emitted from the X-ray source, and a second lattice for interfering with the self-image of the first lattice. X-rays that include a grid and generate a phase contrast image that includes at least one of an absorption image, a phase differential image, and a dark field image based on the X-ray detection signal detected by the detection unit. In the method of adjusting the lattice used in the phase imaging device,
From the adjustment light source arranged between the first lattice and the second lattice, through an opening arranged so that the relative position with the adjustment light source is fixed in the vicinity of the adjustment light source. , The step of irradiating the adjusting light toward either the first grid or the second grid, and
The first reflection adjusting light reflected by either the first lattice or the second lattice and the first reflection adjusting light were reflected by either the first lattice or the second lattice. Around the first direction in the in-plane direction orthogonal to the irradiation axis direction of the X-ray connecting the X-ray source and the detection unit so that the second reflection adjusting light both pass through the opening. Positions of the first lattice and the second lattice in at least one of the first rotation direction of the above and the second rotation direction around the second direction orthogonal to the first direction in the in-plane direction. A grid adjustment method comprising a step of adjusting the deviation. The method for adjusting a grid according to claim 1, wherein the adjusting light includes a laser beam. The method for adjusting a grid according to claim 1, wherein the adjusting light includes visible light. The opening includes a slit
When the step of adjusting the misalignment in the first rotation direction is performed, the slit is arranged so as to extend in the first direction, and the step of adjusting the misalignment in the second rotation direction is performed. The method for adjusting a grid according to claim 1, wherein the grid is arranged so as to extend in the second direction. When the step of adjusting the positional deviation in the first rotation direction is performed, the step of irradiating the adjusting light is inclined in the first direction with respect to the light incident surface of the member on which the slit is formed. When the step of adjusting the misalignment in the second rotation direction is performed, which includes the step of irradiating the adjusting light in the direction in which the slit is formed, the first step is made with respect to the light incident surface of the member on which the slit is formed. The method for adjusting a grid according to claim 4, further comprising a step of irradiating the adjusting light in a direction inclined in two directions. The step of adjusting the misalignment is
A step of adjusting the positional deviation between either the first grid or the second grid and the opening so that the light for adjusting the first reflection passes through the opening.
After performing the step of adjusting the misalignment so that the first reflection adjusting light passes through the opening, the first lattice so that the second reflection adjusting light passes through the opening. The method for adjusting a grid according to claim 1, further comprising a step of adjusting a misalignment between any one of the second grids and either the first grid or the second grid. The step of adjusting the misalignment is
The positional deviation between the first grid and the second grid in the second rotation direction is adjusted so that the first reflection adjusting light and the second reflection adjusting light both pass through the opening. And the process to do
After performing the step of adjusting the positional deviation between the first grid and the second grid in the second rotation direction, the adjusting light source and the opening are rotated by approximately 90 degrees around the irradiation axis direction. , The misalignment between the first grid and the second grid in the first rotation direction so that the first reflection adjusting light and the second reflection adjusting light both pass through the opening. The method for adjusting a grid according to claim 1, further comprising a step of adjusting. In the step of irradiating the adjusting light and the step of adjusting the misalignment, the opening is arranged at the central portion between the first lattice and the second lattice in the irradiation axis direction. The method for adjusting a grid according to claim 1. In the step of adjusting the misalignment, when a lattice pattern is formed on the surface on which the adjustment light is reflected, in the plurality of first reflection adjustment lights generated by being diffracted by the lattice pattern. When the step of adjusting the positional deviation using the first reflection adjusting light having the highest intensity is included and a lattice pattern is formed on the surface on which the first reflection adjusting light is reflected, the lattice The first aspect of the present invention includes a step of adjusting the misalignment using the second reflection adjusting light having the highest intensity in the plurality of the second reflection adjusting lights generated by being diffracted by the pattern. How to adjust the grid. In the step of adjusting the misalignment, the first reflection adjusting light, the second reflection adjusting light, and the second reflection adjusting light are multiple-reflected by the first lattice and the second lattice. 3. The method for adjusting a grid according to claim 1, further comprising a step of adjusting the misalignment based on the light for adjusting reflection. The method for adjusting a grid according to claim 1, wherein the width of the opening is set to be equal to or larger than the spot diameter of the adjusting light.

Images