JP2002058664A - Radiographing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiographing apparatus in which the position of a tube can be easily adjusted corresponding to an imaging condition. SOLUTION: An X-ray tube 41 is supported above the top plate 31 by a tube holding part 42 which is constituted of a rotation part 43 to change the direction of the X-ray tube 41, an elevation part 44 to vertically move the X-ray tube, a slide part 45 to move the top plate 31 in the lateral direction, and a slide part 46 to move the top plate 31 in the longitudinal direction. Further, motors and drive means 47, 48, 49 such as driver, etc., to drive those motors are assemble into the rotation part 43, elevation part 44, and the slide part 45 respectively. Signals from detecting means 36, 37, 38 are sent to the drive means 47, 48, 49 via a tube position control means 50 to move the X-ray tube 41 to an arbitrary position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation photographing apparatus for projecting radiation such as X-rays and photographing the radiation with a radiation receiving section.

[0002]

2. Description of the Related Art Conventionally, a radiographic apparatus has been used in various fields such as medical diagnosis of a subject and nondestructive inspection of a substance, and an intensifying screen and a radiographic film are closely attached to the radiographic apparatus. A so-called radiographic method which is used by being used is used. In these photographing apparatuses, when radiation transmitted through a subject enters an intensifying screen, a phosphor contained in the intensifying screen absorbs the energy of the radiation to generate fluorescent light, and the fluorescent light causes the radiographic film to be exposed. Then, the radiation image is recorded as a visible image.

In recent years, an image recording / reproducing apparatus provided with a radiation detector made of a stimulable phosphor has been proposed.
In this image recording / reproducing apparatus, when radiation passes through a subject and enters the stimulable phosphor, the stimulable phosphor accumulates a part of radiation energy. Subsequently, when the stimulable phosphor is irradiated with visible light or the like, the stimulable phosphor emits stimulated emission according to the stored energy. That is, the stimulable phosphor accumulates radiation image information of the subject, and scans the stimulable phosphor using a scanning unit using excitation light such as laser light, so that the signal reading unit photoelectrically emits the photostimulated emission light. And a recording material such as a photographic photosensitive material or a display means such as a CRT records or displays as a visible image.

[0004] Also, with the progress of semiconductor process technology,
For example, as shown in Japanese Patent Application Laid-Open No. 8-52044, a radiation detector that directly outputs digital radiation in real time has been proposed. This digital radiation detector has a structure in which a scintillator and a solid-state light detector are stacked. The scintillator converts radiation into visible light, and the solid-state light detector photoelectrically converts the visible light converted by the scintillator. This solid-state photodetector is arranged in a matrix on a substrate made of quartz glass with a solid-state photodetector made of a transparent conductive film and a conductive film sandwiched between amorphous semiconductor films.

[0005] Since such a radiation detector is in the form of a flat panel having a thickness of several mm, it is easy to reduce the thickness and weight of an X-ray image receiving unit using the radiation detector. In addition, since the radiation image receiving unit can directly obtain a digital image without using consumable members such as a film and a stimulable phosphor sheet,
Work to set a cassette containing a film or a stimulable phosphor sheet in the radiation receiving unit, which was conventionally required,
The work of taking out the cassette after photographing and developing the image becomes unnecessary.

[0006] For example, FIG. 4 is an explanatory view of a bucky photographing table that can be used for simple photographing of the limbs, head, abdomen, etc. of the subject S.
And is supported by the support 3. An X-ray image receiving unit 4 in which an X-ray detector 4a is incorporated is arranged in a space between the top plate 1 and the support 3. When photographing the subject S lying on the tabletop 1 in the supine or prone position, X-rays are emitted from a tube T located above the subject S and transmitted through the subject S. The X-ray image is received by the X-ray image receiving unit 4.

[0007] As shown in FIG. 5, when photographing the side of the subject S who is supine or prone on the table 1,
A cassette 5 containing a film or a stimulable phosphor sheet is arranged on the edge of the top plate 1 instead of using the X-ray image receiving section 4 arranged below the tube, and a tube located on the side of the subject S X-rays are emitted from the sphere T ′, and X-rays transmitted through the subject S are received by the cassette 5.

[0008] As shown in FIG.
In some cases, an X-ray image receiving unit 4 having a built-in X-ray detector is used, and an imaging stand capable of changing the attitude of the X-ray image receiving unit 4 is used. The imaging table includes a guide rail (not shown) for guiding the X-ray image receiving unit 4 in the short direction of the top 1 and a rotating shaft 6 for rotating the X-ray image receiving unit 4 exposed from the top 1 in the vertical direction.
have. In this imaging table, the X-ray receiving unit 4 can be pulled out to the outside of the tabletop 1 and changed to a horizontal state 4 ′ without the tabletop 1 and a vertical state 4 ″ from the horizontal state 4 ′. The subject S can be easily photographed from different directions by one X-ray image receiving unit 4. In the state 4 'without the table 1, the subject S directly places the hand on the X-ray image receiving unit 4, Since an imaging part such as a foot can be placed, the imaging part can be brought close to the X-ray image receiving unit 4, and a good image free of X-ray absorption and scattering by the top plate 1 can be obtained.

[0009] In this case, when photographing the subject S using the tube T 'located on the side of the subject S, the subject S
When the patient is supine or prone, the entire imaging region of the subject S is located near the top board 1 and sufficiently falls within the imaging range of the X-ray image receiving unit 4.

On the other hand, for example, when the subject S with water or the like accumulated on the chest is laid on the table 1 for imaging, the upper end of the imaging site of the subject S is imaged by the X-ray receiving unit 4. It is necessary to move the X-ray image receiving unit 4 upward from the upper part of the range.

In this type of imaging, a grid is arranged in front of the X-ray image receiving unit 4 in order to reduce the incidence of scattered X-rays generated in the subject S on the X-ray image receiving unit 4. There are many. In this case, since the grid has a focal point, even when the X-ray receiving unit 4 is changed to a vertical state and the image is taken, the tube T ′ is aligned with the center of the imaging range of the X-ray receiving unit 4. Need to be done.

However, as shown in FIG. 7, in order to widen the imaging range, the upper end of the X-ray image receiving unit 4 is set at a high position, and the height h of the tube T 'is made coincident with the center of the imaging range. In this case, even if the imaging of the subject S 'lying sideways can be satisfied, the subject S in the supine or prone low position
Cannot be taken satisfactorily.

As shown in FIG. 8, the X-ray receiving unit 4 is used to satisfy the imaging of the subject S who is lying on his or her back.
Is set low and the height h 'of the tube T matches the center of the imaging range, it is not possible to satisfy the imaging of the high part of the subject S' lying sideways.

For this purpose, an imaging table provided with means for changing the position of the X-ray image receiving section 4 has been devised as shown in FIG. In this imaging table, when the subject is imaged by a tube arranged above the top 1, the X-ray receiving unit 4 is placed in a horizontal state and arranged on the lower surface of the top 1, and the subject is placed on the top 1. The patient 1 is supine or prone, and X-rays are projected from the tube T and received by the X-ray image receiving unit 4.

On the other hand, when the subject S is photographed by the tube T ′ arranged on the side of the top 1, first, the X-ray receiving section 4 is moved along the first guide member 11 by the first sliding member 11. By moving the moving member 12 in the horizontal direction and further sliding the second sliding member 13 in the same direction along the first sliding member 12, the X-ray image receiving section 4 Can be pulled out to expose it horizontally. Subsequently, by rotating the rotation connecting member 14 with respect to the second sliding member 13, the direction of the X-ray image receiving unit 4 can be changed to the vertical state.

FIG. 10 is an enlarged view of a main part of a mechanism for adjusting the position of the X-ray image receiving unit 4. Racks 15 are respectively fixed to both side surfaces of the X-ray image receiving unit 4, and a box-shaped third sliding member 16 fixed to the rotary connecting member 14 is slidably connected. The third sliding member 1
Numeral 6 is slidably attached to the X-ray image receiving unit 4 by fitting a dovetail into a dovetail groove 17 provided in the X-ray image receiving unit 4, for example.

A third sliding member 16 is mounted on the rack 15.
A pinion 19 supported via a gear shaft 18 provided therein is engaged. A wheel gear 20 is coaxially supported on the gear shaft 18, and the wheel gear 20 is meshed with a worm gear 22 supported via a gear shaft 21. Further, a knob 23 is attached to the gear shaft 21 outside the third sliding member 16.

Therefore, when adjusting the relative distance between the top plate 1 and the X-ray receiving unit 4 in the vertical direction, turning the knob 23 rotates the worm gear 22 and the wheel gear 2.
The X and the pinion 19 rotate integrally, and the rack 15 is moved up and down, whereby the X-ray image receiving unit 4 is moved up and down.

As described above, the X-ray image receiving unit 4 for the top 1
The X-ray image receiving unit 4 can be changed in the vertical direction, the X-ray image receiving unit 4 can be moved horizontally, the posture can be changed to the vertical state, and then the vertical position can be changed. The imaging range of the unit 4 can be set according to the subject, so that the subject can be imaged in an optimal state using one X-ray image receiving unit 4, and an X-ray image effective for diagnosis can be obtained. In this way, it is possible to set one X-ray image receiving unit 4 at an optimum position for various required photographing postures.

[0020]

However, in the conventional example described above, when performing various photographing postures,
It is necessary to adjust the position and angle of the X-ray tube, which is the source of X-rays, to an optimum position. In a conventional elevating table in which the height of the top 1 can be varied, the height of the tube changes according to the height of the top 1, and the X-ray image receiving section 4 below the tube and the top 1. An imaging device having means for keeping the distance to the camera constant is used. Thereby, the photographing technician can take a picture at an arbitrary position at the height of the top board 1.

However, movement of the X-ray image receiving unit 4 in the short direction of the top 1, change of the posture to the vertical state at that position, and further movement in the vertical direction in the vertical state are not supported. In addition, each time the X-ray image receiving unit 4 is moved, the technician needs to manually perform the alignment.

In particular, this positioning needs to be performed accurately in photographing using a grid. This means that the grit has a unique focal point, and it is necessary not only to adjust the position of the tube to the center of the imaging range, but also to precisely match the focal length of the grid. For this reason, it is necessary for the photographing technician to perform this operation quickly and accurately while taking into consideration the subject taking the photographing posture.

An object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide a radiation imaging apparatus capable of easily adjusting the position of a tube according to an imaging state.

[0024]

According to the present invention, there is provided a radiographic apparatus for irradiating a subject with radiation, and an X-ray tube supporting the X-ray tube. Part, a top plate for lying down on the subject, a radiation receiving unit disposed below the top plate, a support table for supporting the radiation receiving unit, and the radiation receiving unit in a short direction of the top plate. In a radiation imaging apparatus having a movable mechanism capable of being arranged, a detecting means for detecting a position of the radiation receiving portion in a short direction of the top plate, and the X-ray tube based on an output of the detecting means. Means for matching the position of the radiation receiving section to the center position of the radiation image receiving section.

According to the radiation imaging apparatus of the present invention, there is provided an X-ray tube for irradiating a subject with radiation, a tube holding section for supporting the X-ray tube, a top plate for lying down the subject, A radiation receiving portion disposed below the top plate, a support base for supporting the radiation receiving portion, and the radiation receiving portion can be disposed in a short direction of the top plate and a short side of the top plate A radiation imaging apparatus having a mechanism for converting the position of the radiation image receiving section to a vertical state, a detecting means for detecting a position of the radiation image receiving section in the short direction of the top plate, and an attitude of the radiation image receiving section. And a means for matching the position and orientation of the X-ray tube with the center position of the radiation image receiving section based on the outputs of the two detecting means.

A radiation imaging apparatus according to the present invention comprises a tube for irradiating a subject with radiation, a tube support for supporting the tube, a top plate for lying down on the subject, A radiation receiving portion disposed below, a support base for supporting the radiation receiving portion, and the radiation receiving portion can be disposed in a lateral direction of the top plate, and the radiation is disposed on a lateral side of the top plate. A mechanism that changes the attitude of the image receiving unit to a vertical state and enables the radiation image receiving unit in the vertical state to be movable in a substantially vertical direction. Detecting means for detecting the position; detecting means for detecting the attitude of the radiation receiving section; detecting means for detecting the height of the radiation receiving section in a vertical state; and the tube based on the outputs of the three detecting means. Position and orientation of the sphere at the center of the radiation receiver Characterized by comprising a means for location and the counter matches.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in FIGS. FIG. 1 is a schematic diagram of a radiation imaging apparatus according to the first embodiment. A top plate 31 made of an acrylic plate, a carbon plate, wood, or the like for lying down on a subject is supported by support columns 32 at four corners. It is supported in a substantially horizontal state by 33. An X-ray image receiving unit 34 having a built-in X-ray digital detector is arranged between the top plate 31 and the support 33. Further, a guide mechanism 35 for moving the X-ray image receiving unit 34 along the short direction of the top plate 31
The guide mechanism 35 includes a horizontal position detecting unit 36 that detects the position of the X-ray image receiving unit 34 that moves in the short direction of the top plate 31, and the X-ray image receiving unit 34 is set in a horizontal state or a vertical state. There is provided a posture detecting means 37 for detecting the posture, and a vertical position detecting means 38 for detecting the position of the X-ray image receiving portion 34 in a vertical state.

On the other hand, above the top plate 31, an X-ray tube 41
Are supported by a tube holding section 42, and the rotating section 4 is capable of changing the direction of the X-ray tube 41.
3. It comprises an elevating unit 44 that moves up and down, a slide unit 45 that allows the top plate 31 to move in the short direction, and a slide unit 46 that allows the top plate 31 to move in the longitudinal direction. Further, the rotating unit 43, the elevating unit 44, and the sliding unit 45 incorporate driving means 47, 48, and 49 such as motors and drivers for driving these motors, respectively. The incoming signal is sent via the tube position control means 50 to move the X-ray tube 41 to an arbitrary position.

FIG. 2 is an enlarged view of a main part of the guide mechanism 35.
The state where the X-ray image receiving unit 34 is oriented in the vertical direction is shown.
On both sides of the X-ray image receiving unit 34, a rack 51 is fixed, and a box-shaped sliding member 52 is slidably connected. The sliding member 52 is fixed to a rotary connecting member 53. ing. The X-ray image receiving section 34 and the sliding member 52
Are fitted slidably with each other by a dovetail groove 54 provided in the X-ray image receiving portion 34 and a dovetail provided in the sliding member 52, for example.

The rack 51 meshes with a pinion 56 supported via a gear shaft 55 provided on a sliding member 52. A wheel gear 57 is coaxially supported on the gear shaft 55, and the wheel gear 57 is meshed with a worm gear 59 supported on the sliding member 52 via the gear shaft 58. A knob 60 is attached to the gear shaft 58 outside the sliding member 52. In the sliding member 52, the gear 6 is attached to the pinion 56.
1 is fitted, and a variable resistor 62 such as a potentiometer is supported by the gear 61.

The horizontal position detecting means 36 for detecting the position of the X-ray image receiving section 34 is attached to a guide member 71 fixed to the support 33 in the guide mechanism 35 and the like. The horizontal position detecting means 36 is composed of a wire 72, a gear train 73, and a variable resistor 74 composed of a potentiometer. One end 72a of the wire 72 moves together with the X-ray image receiving section 34, and slides to fix the rotary connecting member 53. It is attached to the moving member 75.

The other end of the wire 72 is wound around the pulley 76 in the gear train 73 a plurality of times. Further, the gear train 73
Is connected to a shaft of a variable resistor 74, and the movement of the X-ray image receiving section 34 pulls the wire 72 in the direction of the arrow, rotates the pulley 76, and rotates the shaft of the variable resistor 74 through the gear train 73. Rotate. Thus, the movement of the X-ray image receiving unit 34 can be obtained as a change in the resistance value of the variable resistor 74.

In the vicinity of the rotary connecting member 53, a posture detecting means 37 composed of a micro switch 77, a photo interrupter and the like is attached. Further, the rotation connecting member 53 is provided with a projection 53a. When the X-ray image receiving section 34 is in a horizontal state, the projection 53a pushes the lever 77a of the micro switch 77, and the X-ray image receiving section 34 When the state is reached, the microswitch 77 is arranged so that the projection 53a is separated from the lever 77a, so that it is possible to detect whether the X-ray image receiving unit 34 is in a horizontal state or a vertical state. .

In using the radiation imaging apparatus having such a configuration, first, when an examinee lying on the top plate 31 is imaged from above, the X-ray image receiving section 34 is set in a horizontal state and the lower surface of the top plate 31 is set. And the X positioned above the top plate 31
An X-ray from the ray tube 41 is irradiated to a subject below.

Next, when photographing is performed without the top plate 31, the X-ray image receiving unit 34 is first drawn out from the lower surface of the top plate 31 to the side of the top plate 31, and the image receiving surface of the X-ray image receiving unit 34 is received. Is exposed. The variable resistor 7 is connected via the pulley 76 and the gear train 73 in accordance with the amount of the X-ray image receiving portion 34 drawn out.
The axis 4 rotates, and the amount of rotation of this axis is output to the bulb position control means 50 as a change in electric resistance inside the variable resistor 74. The tube position control unit 50 outputs a signal to the driving unit 49 so that the X-ray tube 41 is driven by the same distance as the movement amount of the X-ray image receiving unit 34, and the X-ray tube 41
It moves while maintaining the distance Lv between the X-ray tube 41 and the X-ray image receiving unit 34, and stops at a position coincident with the imaging center of the X-ray image receiving unit 34.

Although the X-ray image receiving unit 34 is configured to be detectable even when pulled out by an arbitrary amount, the imaging position is limited to two positions, that is, a position below the top plate 31 and a position where the X-ray receiving position is pulled out. One or two microswitches or other sensors may be used to detect which of these positions is present. In this case, the moving mechanism of the X-ray tube 41 may be configured to automatically stop at two places.

On the other hand, when the subject is imaged from the side, the X-ray image receiving section 34 is pulled out from the top plate 31 and rotated vertically by the rotary connecting member 53. The change in the posture of the X-ray image receiving unit 34 from the horizontal state to the vertical state is detected by the posture detection unit 37, and the information is transmitted to the tube position control unit 5.
Output to 0. The tube position control means 50 is an X-ray tube 41
A signal for rotating the direction of the X-ray tube 41 is sent to the driving means 47 for changing the direction of the X-ray tube 41 so that the X-ray irradiation direction is directed horizontally from below.

A signal is sent to the driving means 49 for moving the X-ray tube 41 in the short direction of the top plate 31 so that the X-ray tube 41 moves to a position separated by an arbitrary horizontal distance Lb. Can be Further, a driving means 48 for raising and lowering the X-ray tube 41
, A signal is sent so that the X-ray tube 41 descends to the height of the imaging center of the X-ray image receiving unit 34 in the vertical state. As a result, the X-ray tube 41 moves to a position facing and coincident with the imaging center of the X-ray image receiving unit 34.

When adjusting the relative distance between the top plate 31 and the X-ray image receiving section 34 in the vertical direction, the knob 60 is rotated in the direction of the arrow. As a result, the worm gear 59 rotates, the wheel gear 57 and the pinion 56 rotate integrally, and the rack 51 is moved to move the X-ray image receiving unit 34 in the vertical direction. Further, the rotation of the pinion 56 is also transmitted to the gear 61, and rotates the shaft of the variable resistor 62. Thus, a change in the vertical position of the X-ray image receiving unit 34 can be obtained as a change in the resistance value of the variable resistor 62.

When the height of the X-ray image receiving portion 34 in the vertical state is changed in this way, the amount of movement is changed as a change in the electric resistance inside the variable resistor 62 and the tube position control means 5
0, the tube position control means 50 outputs X
A signal is output to the driving unit 48 so that the X-ray tube 41 moves by the same distance as the moving amount of the X-ray image receiving unit 34, and the X-ray tube 41 is moved from the X-ray tube 41 to the X-ray image receiving unit 34. Lh
Is moved up and down while maintaining the position, and stops at a position coinciding with the imaging center of the X-ray image receiving unit 34.

FIG. 3 is an explanatory diagram of the second embodiment.
In the first embodiment, the rotating unit 43, the lifting unit 4
4. Driving means 47, 48, 49 such as a motor and a driver for moving the motor are incorporated in the slide portion 45, and the position of the tube is automatically controlled by a signal from the tube position control means 50. In the second embodiment, the rotating unit 43, the elevating unit 44, and the sliding unit 45 do not include a driving unit such as a motor. Instead, tube position detecting units 81, 82, and 83 are provided instead. These outputs are connected to a position comparing means 84.

The position comparing means 84 includes a horizontal position detecting means 36 for detecting the position of the X-ray image receiving section 34 which moves in the short direction of the top plate 31 as in the first embodiment, and a posture detecting means. 37, a signal from the vertical position detecting means 38 is input.

With this configuration, when the position of the X-ray image receiving section 34 changes, the photographing technician manually operates the X-ray tube 41.
Move the position of. The amount of movement is detected by each tube position detecting means 81, 82, 83 and sent to the position comparing means 84. Then, the detecting means 36 on the X-ray image receiving unit 34 side,
The lock signal is compared with the required movement amount calculated from 37 and 38, and when they match, the lock signal is sent to each holding unit, that is, the rotating unit 43, the elevating unit 44, so that the X-ray tube 41 is fixed at that position.
The X-ray tube 41 is sent to the slide portion 45, and the lock mechanism (not shown) is operated to fix the X-ray tube 41.

In this case, as compared with the first embodiment,
Although the photographing technician needs to move the tube, there is no need for a tube moving mechanism, and there is an advantage that the entire apparatus can be simplified and the cost can be reduced.

In these embodiments, an example is shown in which a radiation detector is used in the X-ray image receiving unit. However, the present invention is not limited to this. For example, the same effect can be obtained by using a cassette in which a film or a stimulable phosphor sheet is placed in the X-ray image receiving portion.

[0046]

As described above, the radiation imaging apparatus according to the present invention is designed so that the radiation receiving section set in a horizontal state or a vertical state so that the subject can be optimally imaged is provided with the tube. By having means for moving the position,
The burden on the imaging technician can be reduced, and imaging failure due to misalignment can be prevented beforehand, and a radiation image effective for diagnosis can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a first embodiment of a radiation imaging apparatus.

FIG. 2 is an enlarged perspective view of a main part of a guide mechanism.

FIG. 3 is a configuration diagram of a second embodiment.

FIG. 4 is an explanatory diagram of a conventional example.

FIG. 5 is an explanatory diagram of a conventional example.

FIG. 6 is an explanatory diagram of a conventional example.

FIG. 7 is an explanatory diagram of a conventional example.

FIG. 8 is an explanatory diagram of a conventional example.

FIG. 9 is a partially cutaway perspective view of a conventional example.

FIG. 10 is an enlarged perspective view of a main part of a conventional example.

[Explanation of symbols]

 31 top plate 32 support 33 support stand 34 X-ray image receiving unit 35 guide mechanism 36, 37, 38 detecting means 41 X-ray tube 42 tube holding unit 47, 48, 49 tube driving unit 50 tube position control unit 52, 75 sliding member 53 rotation connecting member 81, 82, 83 tube position detecting means 84 position comparing means

Claims (3)

[Claims] 1. An X-ray tube for irradiating a subject with radiation,
A tube holding unit that supports the X-ray tube, a top plate on which the subject lies, a radiation image receiving unit disposed below the top plate, a support table that supports the radiation image receiving unit, In a radiation imaging apparatus having a moving mechanism capable of disposing an image receiving unit in a short direction of the top plate, a detecting unit configured to detect a position of the radiation receiving unit in the short direction of the top plate, Means for matching the position of the X-ray tube with the center position of the radiation image receiving unit based on the output of the means. 2. An X-ray tube for irradiating a subject with radiation,
A tube holding unit that supports the X-ray tube, a top plate on which the subject lies, a radiation image receiving unit disposed below the top plate, a support table that supports the radiation image receiving unit, A mechanism capable of disposing the image receiving section in the short direction of the top plate and a mechanism for changing the attitude of the radiation receiving section to a vertical state on the short side of the top plate, wherein the radiation receiving section is Detecting means for detecting the position of the top plate in the lateral direction, detecting means for detecting the attitude of the radiation image receiving unit, and the position and orientation of the X-ray tube based on the outputs of the two detecting means. Means for causing the radiation image receiving unit to face and match the center position of the radiation image receiving unit. 3. A tube for irradiating a subject with radiation, a tube support for supporting the tube, a top plate for lying down on the subject, and a radiation image receiving unit disposed below the top plate. And a support base for supporting the radiation image receiving unit, and the radiation image receiving unit can be arranged in the short direction of the top plate, and the radiation image receiving unit is vertically positioned on the short side of the top plate. In a radiation imaging apparatus having a mechanism that enables the converted radiation image receiving unit to be moved in a substantially vertical direction in a vertical state, a detection unit that detects a position of the radiation image receiving unit in a short direction of the top plate, Detecting means for detecting the attitude of the radiation receiving section, detecting means for detecting the height of the radiation receiving section in a vertical state, and the position and orientation of the tube based on the outputs of the three detecting means. Means for matching the center position of the radiation receiving section A radiographic apparatus characterized by the following.