JP2007130058A - Radiation imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the readiness of loading or unloading of a radiation image detector in the use of a radiation shielding member in a radiation imaging apparatus for phase contrast imaging. <P>SOLUTION: The mammal imaging apparatus 1 has a first radiation shielding member 21 in which an opening part is formed at a position corresponding to a loading/unloading port of the radiation image detector in a detector holding member 12 to cover a space between a subject table 10 and the detector holding member 12 and a second radiation shielding member 22 which covers a space when the distance between the subject table 10 and the detector holding member 12 is increased at the rate of enlargement to generate a space between the subject table 19 and the first radiation shielding member 21. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a radiographic image capturing apparatus, and more particularly to a radiographic image capturing apparatus capable of capturing a phase contrast image.

  In general, a radiographic imaging apparatus that uses an action of radiation passing through a substance is widely used for medical image diagnosis, non-destructive inspection, and the like. In particular, for radiographic imaging apparatuses used for mammography, a method has been used in which a subject is fixed on a subject table integrated with a radiographic image detector. However, according to this method, the subject is photographed at the actual size, but the contrast of the image is not sufficiently increased, and the medical photographing used for deciphering the fine structure of a specific part such as a lesion part of the breast. There was a problem that the image was not sharp enough as an apparatus.

  Therefore, in recent years, a radiographic image capturing apparatus that captures a phase contrast image has been proposed. The phase contrast image is also called a refraction contrast image, and was previously obtained by imaging with monochromatic parallel radiation obtained from a radiation source such as SPring-8 or imaging with a microfocus radiation source having a focal size of about 10 μm. As has been said, it has been found that a radiation source (small focus radiation source having a focal size of 30 to 300 μm) used in a general medical facility can also be obtained. The phase contrast image can depict a high contrast of the boundary of the subject as compared with an image having only an ordinary absorption contrast, and a high-definition radiation image can be obtained.

  In capturing this phase contrast image, it is necessary to provide a certain distance between the subject and the radiation image detector. Therefore, for example, in a radiographic imaging apparatus that captures a breast, a space is generated between a subject table that holds a subject and a radiographic image detector, and a part of the subject's body is captured in this space when imaging is performed. May enter and be exposed to radiation and be exposed to radiation. In addition, the subject's body or dust entering the space is reflected in the photographed image, and there is a problem that phase contrast photographing for precise photographing of the subject becomes an obstacle.

In order to solve such a problem, for example, in Patent Document 1, as shown in FIG. 9, the movable range of the detector holding member 12, which is a range between the detector holding member 12 and the subject table 10. A breast imaging apparatus having a length dimension corresponding to the position of the detector holding member 12 when the interval is maximized and provided with a radiation shielding member 23 having the same width dimension as that of the subject table 10 is described. ing. In Patent Document 1, as shown in FIGS. 10A and 10B, two plates overlap at a position below the front end portion of the subject table 10 and in contact with the end portion of the detector holding member 12. When the radiation shielding member 23 having a matching structure is provided and the detector holding member 12 moves along the guide rail, the two plates of the radiation shielding member 23 are moved in sliding contact with each other. Accordingly, there is also described a mammography apparatus that is slid in the moving direction of the detector holding member 12.
JP 2004-229900 A

  However, in the technique described in Patent Document 1, since the end of the detector holding member 12 on the insertion side of the radiation image detector is in contact with the radiation shielding member 23, the radiation in the detector holding member 12 is There is a problem that the end portion on the side of the attachment / detachment opening for attaching / detaching the image detector is blocked by the radiation shielding member 23, and it is difficult to attach / detach the radiation image detector. Further, the technique shown in FIG. 10 has a problem that the photographing magnification that can be photographed is limited by the length of the two radiation shielding members 23.

  The subject of this invention is improving the ease of attachment or detachment of the radiographic image detector at the time of using a radiation shielding member in the radiographic imaging apparatus which performs a phase contrast imaging.

In order to solve the above-mentioned problem, the invention described in claim 1
A radiation source that irradiates the subject with radiation; a detector holding member that is disposed at a position in front of the radiation in the radiation direction and that attaches and detaches the radiation image detector; and the radiation source for placing the subject Radiation capable of phase contrast imaging, comprising: a subject table disposed between the detector holding member; and an adjustment unit that adjusts a distance between the subject table and the detector holding member according to an imaging magnification. In the image capturing device,
A radiation shielding member is provided to cover the space between the object table and the detector holding member, and the radiation image detector can pass through a position corresponding to the attachment / detachment opening of the radiation holding member in the detector holding member. An opening is formed.

The invention according to claim 2 is the invention according to claim 1,
The radiation shielding member includes a first radiation shielding member that covers a space between the subject table and the detector holding member at the time of imaging at a first imaging magnification, and a space between the subject table and the detector holding member. Covers the space created between the first radiation shielding member and the subject table at the time of photographing at the second photographing magnification, where the distance is relatively longer than that at the time of photographing at the first photographing magnification. And a second radiation shielding member, wherein the opening is formed in the first radiation shielding member.

The invention according to claim 3 is the invention according to claim 1 or 2,
A holding member for maintaining the radiation source and the detector holding member at a constant distance;
The adjusting unit adjusts a relative distance between the radiation source and the detector holding member with respect to the subject table in accordance with an imaging magnification.

  According to the first aspect of the present invention, in the radiographic imaging apparatus that performs phase contrast imaging, it is possible to improve the detachability of the radiographic image detector when using the radiation shielding member.

  According to the second aspect of the present invention, it is possible to perform imaging using the radiation shielding member at any of the first and second imaging magnifications, and the radiation image detector can be used while using the radiation shielding member. It can be easily attached and detached.

  According to the third aspect of the present invention, in the radiographic imaging apparatus having the holding member for maintaining the radiation source and the detector holding member at a certain distance, the radiographic image detection when the radiation shielding member is used. The ease of attachment / detachment of the vessel can be improved.

A breast image capturing apparatus 1 according to the present embodiment is a radiographic image capturing apparatus that performs phase contrast imaging. Hereinafter, the configuration of the breast image capturing apparatus 1 will be described with reference to the drawings.
1 to 3 show a configuration example of the breast image photographing apparatus 1. FIG. 1 is a right side view of the appearance of the mammography apparatus 1 to which the first radiation shielding member 21 is attached, and FIG. 2 is a view to which the first radiation shielding member 21 and the second radiation shielding member 22 are attached. 2 is an external right side view of the breast image capturing apparatus 1. FIG. FIG. 3 is a diagram schematically showing an internal configuration of the imaging apparatus main body 2 of the breast imaging apparatus 1 shown in FIGS. In FIG. 3, the operation device 14, the power supply unit 15, the drive device 17, and the drive device 19 are connected to the control device 16 (shown in FIG. 4) of the main body unit 9, but are not shown here. As shown in FIGS. 1 and 2, in the mammography apparatus 1, a support base 3 is provided on a main body 9 so as to be movable up and down, and a support shaft provided on the support base 3 is provided on the support base 3. The photographing apparatus main body 2 is supported via 4. The support base 3 is moved up and down by being driven by a drive device 17 constituted by a motor or the like. The imaging device main body 2 can be raised and lowered by raising and lowering the support base 3 by the drive device 17, and can be rotated by the drive device 17 with the support shaft 4 as a fulcrum.

  A radiation source 6 for emitting radiation is provided on the upper part of the imaging apparatus main body 2, and the radiation source 6 is connected to the main body 9 via the support shaft 4 and the support base 3. It is connected to the. The radiation source 6 is applied with a tube voltage and a tube current by the power supply unit 15. The radiation source of the radiation source 6 is provided with a throttle port of a diaphragm device 7 as an irradiation field adjustment device that adjusts the radiation field, so that the radiation field can be opened and closed.

  The radiation source 6 is preferably a rotary anode X-ray tube. In this rotary anode X-ray tube, X-rays are generated when an electron beam emitted from the cathode collides with the anode. This is incoherent (incoherent) like natural light, and is not divergent X-rays but divergent light. If the electron beam continues to hit the place where the anode is fixed, the anode is damaged by the generation of heat. Therefore, in an X-ray tube that is usually used, the anode is rotated to prevent the anode from being shortened. An electron beam is made to collide with a plane of a certain size of the anode, and the generated X-rays are emitted toward the subject H from the plane of the certain size of the anode. This plane is called a focus. The focal point size D (μm) indicates the length of one side when the focal point is a square, the short side when the focal point is a rectangle or a polygon, and the diameter when the focal point is a circle.

  As the focal spot size D increases, the amount of radiation applied increases. Since a radiation dose of a certain level or more is practically required to pass through the human body, the breast image capturing apparatus 1 can irradiate the radiation dose necessary for photographing the human body, and the focal spot size D is D ≧ 30 (μm). The radiation source 6) is preferred.

  A detector holding member 12 that holds a cassette containing, for example, a stimulable phosphor sheet serving as a radiation image detector that detects radiation transmitted through the subject H is located below the subject table 10 below the imaging apparatus main body 2. And it is attached to the radiation irradiation direction front position of the radiation source 6. The detector holding member 12 has an attachment / detachment opening 12c (see FIG. 6) for attaching / detaching the radiation image detector on the front surface thereof. The attachment / detachment opening 12c is attached to the detector holding member 12 and held by the detector holding member 12. The uppermost surface of the radiation image detector coincides with the uppermost surface of the detector holding member 12. The radiation source 6 and the detector holding member 12 are attached to the holding member 8 as shown in FIG. 3, and the distance L (R1 + R2 to be described later) between the radiation source 6 and the detector holding member 12 is set by this holding member 8. It is maintained at a certain distance. The holding member 8 is movable in a direction perpendicular to the radiation irradiation surface of the subject table 10 by driving a driving device 19 constituted by a motor or the like. 6 and the detector holding member 12 move while maintaining a certain distance. The distance L between the radiation source 6 and the detector holding member 12 is preferably L ≧ 0.95 (m) from the viewpoint of the visibility of the edge enhancement effect (phase contrast effect) at the time of outputting a captured image.

  As the radiation image detector, for example, a screen (intensifying screen) / film, an FPD (flat panel detector), or the like may be used in addition to the cassette containing the photostimulable phosphor sheet.

  Between the radiation source 6 and the detector holding member 12 in the imaging apparatus main body 2, a subject table 10 on which the subject H is placed and a compression plate 11 for compressing and fixing the subject H from above are arranged. ing. As shown in FIG. 3, the subject table 10 is attached to the holder 5 of the photographing apparatus main body 2 and moves up and down in accordance with the raising and lowering of the photographing apparatus main body 2 by the driving device 17. Thereby, the height of the subject table 10 can be adjusted according to the position of the subject H (breast position). Further, the subject table 10 is provided with an engaging recess 10c for engaging the locking projection 22c (see FIG. 7) of the second radiation shielding member 22. Further, on the left and right side surfaces of the subject table 10, a magnet provided on the inner surface of the second radiation shielding member 22 when the engaging projection 22 c of the second radiation shielding member 22 is engaged with the engagement recess 10 c. Magnetic metal plates 10a and 10b are provided at positions corresponding to 22a and 22b.

The compression plate 11 is configured to be movable along a support shaft (not shown) provided in the photographing apparatus main body 2.
The position of the compression plate 11 is detected by a position detection unit 18 (shown in FIG. 4) and output to the control device 16 of the main body unit 9. As the position detection unit 18, a method using photometry using infrared rays, a method in which a line resistance is provided on the rail of the support shaft that slides the compression plate 11, and a position is determined based on the resistance value measurement can be employed.

  On the surface opposite to the surface of the detector holding member 12 that faces the subject table 10, a radiation dose detection unit 13 that detects the irradiated radiation dose is provided, and the radiation dose detected by the radiation dose detection unit 13. Is output to the control device 16 of the main body 9.

  The main body 9 includes a control device 16 configured by a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). FIG. 4 shows a functional configuration example of the breast image photographing apparatus 1. As shown in FIG. 4, the control device 16 includes a radiation dose detection unit 13 that detects the irradiated radiation dose, a keyboard and touch panel for inputting imaging conditions, and a position for adjusting the position of the subject table 10. Input device 14a having an adjustment switch (upward adjustment switch for upward adjustment, downward adjustment switch for downward adjustment) and the like, an operation device 14 having a display device 14b such as a CRT display or a liquid crystal display, and a power source as a power source of the device The movement of the holding member 8, the driving device 17 that moves the imaging device main body 2 up and down and rotates the imaging device main body 2 by raising and lowering the support base 3, the position detection unit 18 that detects the position of the compression plate 11, A driving device 19 is connected via a bus 20.

  The ROM of the control device 16 stores a control program for controlling each part of the mammography apparatus 1, and the CPU controls the operation of each part of the mammography apparatus 1 in cooperation with this control program. Control and perform phase contrast photography. For example, when the input device 14a is operated by an operator such as a photographing engineer and a photographing condition including a photographing direction is input, the CPU is configured so that the inputted photographing direction requires the rotation of the photographing device main body 2. In the case of an imaging direction that requires rotation, for example, in the case of an MLO (Medio-Lateral Oblique) that images the breast from the oblique direction, the driving device 17 is controlled to control the imaging device. The entire main body 2 is rotated by a predetermined amount. In addition, when the position adjustment switch of the input device 14a is pressed, the CPU controls the driving device 17 in accordance with this to adjust the position of the subject table 10, and the operator adjusts the position of the compression plate 11. When the subject H is pressed and fixed and an enlargement factor in phase contrast photography is input by the input device 14a, the drive device 19 is controlled and held in accordance with the positions of the subject table 10 and the compression plate 11 and the inputted enlargement factor. The relative distance between the radiation source 6 and the detector holding member 12 with respect to the subject table 10 is adjusted by moving the member 8 in a direction perpendicular to the radiation irradiation surface of the subject table 10. When imaging is instructed by the input device 14a, the power supply unit 15 applies a tube voltage and a tube current to the radiation source 6 to irradiate the subject H with radiation, and is input from the radiation dose detection unit 13. When the radiation dose reaches a preset radiation dose, the power supply unit 15 stops radiation from the radiation source 6.

  When the control device 16 controls the drive device 19 to move the holding member 8, an adjustment unit that adjusts the relative distance between the radiation source 6 and the detector holding member 12 with respect to the subject table 10 is realized.

  Here, the principle of phase contrast imaging will be described with reference to FIG. Phase contrast imaging is to obtain an edge-enhanced (refractive contrast-enhanced) image resulting from refraction of radiation as shown in FIG. 5 by providing a constant distance R2 between the subject H and the radiation image detector. is there. As schematically illustrated in FIG. 5, the radiation density is refracted when passing through the object and the radiation density inside the boundary of the object becomes sparse, and the outside of the object overlaps with the radiation that does not pass through the object. To rise. In this way, the edge that is the subject boundary portion is enhanced as an image. This is a phenomenon resulting from the difference in refractive index between the object and air with respect to radiation. This is an edge-enhanced image.

  Further, not only the edge enhancement at the boundary between the air and the subject shown in principle in FIG. 5, but also the boundary portion of the portion having a different refractive index can be obtained in the object. The subject boundary portion in the present invention can be expressed as a boundary portion with a substance having a different refractive index of radiation.

When phase contrast imaging is performed, if the distance from the radiation source 6 to the subject H is R1, and the distance between the subject H and the radiographic image detector is R2, the magnification ratio = (R1 + R2) / R1 is magnified at the imaging magnification. . As for R1, the starting point is the position of the focal point of the radiation source 6, and the location of the radiation source 6 is clearly shown in the normal commercial radiation source 6. The end point is the center line of the subject H fixed by the subject table 10 that fixes the subject position. Here, the position that is equidistant from the subject table 10 and the compression plate 11 is the center line of the subject H. For R2, the starting point is the center line of the subject H, and the ending point is the uppermost surface of the plane that receives the radiation of the radiation image detector, that is, the uppermost surface of the detector holding member 12.
In the present embodiment, it is assumed that the breast image capturing apparatus 1 captures an image at an enlargement ratio (imaging magnification) of 1.46 times, 1.75 times, or 2.63 times.

  In phase contrast imaging, as described above, a certain distance R2 is provided between the subject table 10 and the detector holding member 12 in accordance with the enlargement ratio. The space between the subject 10 and the detector holding member 12 is covered in order to prevent a part other than the photographing part of the subject who provides the subject H from being exposed or being reflected in the image. A radiation shielding member is provided. This radiation shielding member is made of lead or lead glass. In addition, in order to increase the strength, resin and lead may be used as plywood, or a metal plate such as iron or stainless steel and lead may be used as plywood.

In the present embodiment, the mammography apparatus 1 is configured such that the first radiation shielding member 21 and / or the second radiation shielding member 22 are detachable in accordance with the enlargement ratio.
Hereinafter, the first radiation shielding member 21 and the second radiation shielding member 22 will be described with reference to FIGS.

  FIG. 6 is a diagram schematically illustrating the subject table 10, the detector holding member 12, and the first radiation shielding member 21. As shown in FIG. 6, the first radiation shielding member 21 is configured to be attachable to the detector holding member 12, and has a minimum magnification (first imaging magnification: 1.46 here) in the breast imaging apparatus 1. The height h1, the width w1, and the depth w2 are determined so as to cover the space between the subject table 10 and the detector holding member 12. The first radiation shielding member 21 has screw holes 21a and 21b. The screw hole 21a is a screw hole 12a provided in the detector holding member 12, and the screw hole 21b is a screw hole 12b (not shown). It is possible to fix to the detector holding member 12 by inserting each screw according to the above. When the first radiation shielding member 21 is mounted on the detector holding member 12 and the relative distance between the subject table 10 and the radiation source 6 and the detector holding member 12 is adjusted for imaging at the minimum magnification, breast imaging is performed. The device 1 is in the state shown in FIG.

  The mammography apparatus 1 performs phase contrast imaging, and the first radiation shielding member 21 is always mounted on the breast because the first radiation shielding member 21 must be attached at any magnification. It is in a state of being attached to the image photographing device 1. When performing absorption contrast imaging, it is possible to perform imaging by removing the first radiation shielding member 21.

  The first radiation shielding member 21 has an opening 21 c at a position corresponding to the attachment / detachment port 12 c of the detector holding member 12 when the first radiation shielding member 21 is attached to the detector holding member 12. The radiation image detector can be attached / detached from the attachment / detachment opening 12c of the detector holding member 12 with the first radiation shielding member 21 attached through the opening 21c.

  7A is a schematic view of the subject table 10 and the second radiation shielding member 22 as viewed from the side, and FIG. 7B is a schematic view of the second radiation shielding member 22 as viewed from above. (A) is the schematic diagram which looked at the state which mounted | wore with the 1st radiation shielding member 21 and the 2nd radiation shielding member 22, and FIG.8 (b) is the 1st radiation shielding member 21 and the 2nd It is the schematic diagram which looked at the state equipped with radiation shielding member 22 from the front. The second radiation shielding member 22 is attached to the subject table 10, and as shown in FIGS. 7A and 7B, the engagement recess of the subject table 10 is formed at the end of the subject table 10. An engaging projection 22c having a hook-like cross section that can be engaged with the object 10c is provided, and magnets 22a and 22b as fixing members are provided at positions that overlap the object table 10 when mounted on the object table 10. By engaging the locking projection 22 c of the second radiation shielding member 22 with the engagement recess 10 c of the subject table 10, the magnets 22 a and 22 b are attracted to the magnetic metal plates 10 a and 10 b of the subject table 10. The second radiation shielding member 22 is formed by the engagement between the locking projection 22c and the engagement recess 10c, the adsorption between the magnet 22a and the magnetic metal plate 10a, and the adsorption between the magnet 22b and the magnetic metal plate 10b. It can be fixed to the subject table 10.

  The second radiation shielding member 22 is set to an enlargement ratio (second imaging magnification) larger than the minimum magnification that is the first imaging magnification, and the distance between the subject table 10 and the detector holding member 12 is set to be the same. When the space becomes longer than the minimum magnification and a space is formed between the subject table 10 and the first radiation shielding member 21, this space is covered. The height h2 is determined so as to cover the space between the subject table 10 and the first radiation shielding member 21 according to the enlargement ratio of 1.76 or 2.63 times. When there are a plurality of magnifying ratios that are larger than the minimum magnifying ratio and can be photographed, the second radiation shielding member 22 may be prepared for each magnifying ratio, or a high value corresponding to the maximum magnifying ratio that can be photographed. A second radiation shielding member 22 having a thickness may be prepared. The first radiation shielding member 21 and the second radiation shielding member 22 are adjusted by adjusting the relative distance between the object table 10, the radiation source 6 and the detector holding member 12 for photographing at a magnification larger than the minimum magnification. 2, the entire breast image capturing apparatus 1 is in the state shown in FIG.

  Even in a state in which the first radiation shielding member 21 and the second radiation shielding member 22 are mounted, as shown in FIG. 8B, radiation is emitted from the attachment / detachment port 12c of the detector holding member 12 through the opening 21c. It is possible to attach and detach the image detector.

  With the above configuration, at the time of phase contrast imaging, an operator such as an imaging engineer attaches the radiation image detector to the detector holding member 12 through the opening 21c of the first radiation shielding member 21, and the operator inputs the input device 14a. When the position adjustment switch is operated and the photographing direction is input, the driving device 17 is controlled by the control device 16 according to the operation of the operator, and the subject table 10 is positioned at a position corresponding to the height of the subject H and the photographing direction. Is adjusted. After the subject H is positioned, when the operator inputs an enlargement ratio from the input device 14a and sets the position of the compression plate 11, the control device 16 controls the drive device 19, and the holding member 8 is moved according to the enlargement ratio. Thus, the relative distance between the radiation source 6 and the detector holding member 12 with respect to the subject table 10 is adjusted while the relative distance between the radiation source 6 and the detector holding member 12 is maintained constant. Then, if necessary, the operator wears the second radiation shielding member 22 corresponding to the enlargement ratio according to the enlargement ratio, and issues an imaging instruction using the input device 14a. At the time of mounting the second radiation shielding member 22, the operator only needs to engage the locking projection 22 c of the second radiation shielding member 22 with the engagement recess 10 c of the subject table 10. When shooting is instructed, the control device 16 performs shooting. At the time of imaging, the radiation shielding member 21 and / or the radiation shielding member 22 can prevent intrusion from the outside into the radiation irradiation region between the subject table 10 and the detector holding member 12, thereby imaging the patient. It is possible to prevent exposure to parts other than the part and reflection in the image.

  As described above, according to the mammography apparatus 1, the radiation shielding member includes the first radiation shielding member having the opening 21c and common to all magnifications, and the second radiation detachable according to the magnification. By adopting the radiation shielding member, the radiation image detector can be easily attached to and detached from the detector holding member 12 while the first radiation shielding member 21 required at any magnification is attached to the breast imaging apparatus 1. It is possible to improve the ease of attaching and detaching the radiation image detector when using the radiation shielding member.

  In addition, the description content in the said embodiment is a suitable example of the mammography apparatus 1 which concerns on this invention, and is not limited to this.

  For example, in the first and second embodiments described above, the present invention is a mammography apparatus having a configuration in which the distance L (R1 + R2) between the radiation source 6 and the radiation image detector (detector holding member 12) is fixed. However, the present invention can also be applied to a mammography apparatus having a configuration in which R1 is fixed and R2 is moved according to the imaging magnification.

  In addition, the detailed configuration and detailed operation of the mammography apparatus 1 can be changed as appropriate without departing from the spirit of the present invention.

It is a figure which shows the external appearance right side surface of the mammography apparatus 1 with which the 1st radiation shielding member 21 was mounted | worn. It is a figure which shows the external appearance right side surface of the mammography apparatus 1 which mounted | wore with the 1st radiation shielding member 21 and the 2nd radiation shielding member 22. FIG. It is a figure which shows typically the internal structure of the imaging device main-body part 2 of the breast image imaging device 1. FIG. 2 is a block diagram showing a functional configuration of the breast image capturing apparatus 1. FIG. It is a figure for demonstrating the principle of phase contrast imaging. FIG. 3 is a diagram schematically showing a subject table 10, a detector holding member 12, and a first radiation shielding member 21. (A) is the schematic diagram which looked at the to-be-photographed object base 10 and the 2nd radiation shielding member 22 from the right side surface, (b) is the schematic diagram which looked at the 2nd radiation shielding member 22 from the upper surface. (A) is the schematic diagram which looked at the state equipped with the 1st radiation shielding member 21 and the 2nd radiation shielding member 22 from the right side, (b) is the 1st radiation shielding member 21 and the 2nd radiation. It is the schematic diagram which looked at the state equipped with shielding member 22 from the front. It is a figure for demonstrating the prior art. It is a figure for demonstrating the prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mammography apparatus 2 Imaging apparatus main-body part 3 Support base 4 Support axis 5 Holder 6 Radiation source 7 Diaphragm apparatus 8 Holding member 9 Main-body part 10 Subject base 10a, 10b Magnetic metal plate 10c Engaging recessed part 11 Compression plate 12 Detection Device holding member 12a, 12b Screw hole 12c Removable port 13 Radiation dose detection unit 14 Operation device 14a Input device 14b Display device 15 Power supply unit 16 Control device 17 Drive device 18 Position detection unit 19 Drive device 20 Bus 21 First radiation shielding member 21a, 21b Screw hole 21c Opening 22 Second radiation shielding member 22a, 22b Magnet 22c Locking projection

Claims (3)

A radiation source that irradiates the subject with radiation; a detector holding member that is disposed at a position in front of the radiation in the radiation direction and that attaches and detaches the radiation image detector; and the radiation source for placing the subject Radiation capable of phase contrast imaging, comprising: a subject table disposed between the detector holding member; and an adjustment unit that adjusts a distance between the subject table and the detector holding member according to an imaging magnification. In the image capturing device,
A radiation shielding member is provided to cover the space between the object table and the detector holding member, and the radiation image detector can pass through a position corresponding to the attachment / detachment opening of the radiation holding member in the detector holding member. A radiographic imaging device, wherein an opening is formed.   The radiation shielding member includes a first radiation shielding member that covers a space between the subject table and the detector holding member at the time of imaging at a first imaging magnification, and a space between the subject table and the detector holding member. Covers the space created between the first radiation shielding member and the subject table at the time of photographing at the second photographing magnification, where the distance is relatively longer than that at the time of photographing at the first photographing magnification. The radiation image capturing apparatus according to claim 1, further comprising: a second radiation shielding member, wherein the opening is formed in the first radiation shielding member. A holding member for maintaining the radiation source and the detector holding member at a constant distance;
3. The radiographic image capturing apparatus according to claim 1, wherein the adjusting unit adjusts a relative distance between the radiation source and the detector holding member with respect to the subject table in accordance with an imaging magnification.

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