X-ray imaging device and X-ray imaging device position offset detection unit

Abstract

The present invention provides an X-ray imaging apparatus and a position offset detection unit for an X-ray imaging apparatus. The X-ray imaging apparatus includes an X-ray irradiation unit, an X-ray detection unit, a moving mechanism unit that can move while supporting the X-ray irradiation unit, an optical feature point acquisition unit disposed on either the X-ray irradiation unit or the X-ray detection unit and acquiring the position of the feature point by optically detecting the feature point disposed on the other part, a position offset acquisition unit that acquires the position offset between the X-ray irradiation unit and the X-ray detection unit based on the position of the feature point, and a notification unit that provides notification based on the position offset.

Description

Technical Field

[0001] This invention relates to an X-ray imaging device and a position offset detection unit for an X-ray imaging device, and more particularly to an X-ray imaging device and a position offset detection unit for an X-ray imaging device for detecting the position offset between the relative positions of an X-ray irradiation part and an X-ray detection part. Background Technology

[0002] Previously, an X-ray imaging apparatus and a position offset detection unit for an X-ray imaging apparatus were known for detecting the positional offset between the X-ray irradiation part and the X-ray detection part. For example, such an X-ray imaging apparatus and a position offset detection unit for an X-ray imaging apparatus were disclosed in Japanese Patent Application Publication No. 2013-523396.

[0003] The radiographic apparatus disclosed in Japanese Patent Application Publication No. 2013-523396 includes a radiation source, a display, a collimator, and a display device. Furthermore, a sensor element is provided in the collimator disclosed in Japanese Patent Application Publication No. 2013-523396. Additionally, Japanese Patent Application Publication No. 2013-523396 discloses a structure including a holding member for holding the display. The holding member holds the display and also holds an electromagnetic coil. Japanese Patent Application Publication No. 2013-523396 discloses a structure in which the positional shift between the radiation source and the display is detected by using a sensor element provided in the collimator to detect electromagnetic waves emitted from the electromagnetic coil held by the holding member.

[0004] However, as disclosed in Japanese Patent Publication No. 2013-523396, the structure that detects electromagnetic waves emitted from an electromagnetic coil by a sensor element has the following problem: the detection accuracy of the sensor element decreases due to electromagnetic waves emitted from electronic devices located near the radiographic device (X-ray imaging device). When the detection accuracy of the sensor element decreases, the detection accuracy of the positional offset between the radiation source (X-ray irradiation unit) and the display (X-ray detection unit) decreases. Summary of the Invention

[0005] The problem the invention aims to solve

[0006] The present invention was made to solve the above-mentioned problems. One object of the present invention is to provide an X-ray imaging apparatus and a position offset detection unit for an X-ray imaging apparatus that can suppress the decrease in detection accuracy due to positional offset between the X-ray irradiation unit and the X-ray detection unit caused by the surrounding electronic equipment.

[0007] Solution for solving the problem

[0008] To achieve the above objectives, the X-ray imaging apparatus of the first aspect of the present invention comprises: an X-ray irradiation unit that irradiates a subject with X-rays; an X-ray detection unit disposed during X-ray irradiation and used to detect X-rays irradiated from the X-ray irradiation unit; a moving mechanism unit that is movable while supporting the X-ray irradiation unit; an optical feature point acquisition unit disposed on either the X-ray irradiation unit or the X-ray detection unit, which acquires the position of a feature point by optically detecting the feature point disposed on the other of the X-ray irradiation unit and the X-ray detection unit; a position offset acquisition unit that acquires the position offset between the X-ray irradiation unit and the X-ray detection unit based on the position of the feature point acquired by the optical feature point acquisition unit; and a notification unit that provides notification based on the position offset acquired by the position offset acquisition unit.

[0009] Furthermore, to achieve the above-mentioned objective, the position offset detection unit for an X-ray imaging apparatus according to the second aspect of the present invention is used in an X-ray imaging apparatus, the X-ray imaging apparatus comprising: an X-ray irradiation unit that irradiates an object with X-rays; an X-ray detection unit configured during X-ray irradiation and used to detect X-rays irradiated from the X-ray irradiation unit; and a moving mechanism unit capable of moving while supporting the X-ray irradiation unit. The position offset detection unit for the X-ray imaging apparatus comprises: an optical feature point acquisition unit disposed on either the X-ray irradiation unit or the X-ray detection unit, which acquires the position of a feature point by optically detecting the feature point disposed on the other of the X-ray irradiation unit and the X-ray detection unit; a position offset acquisition unit that acquires the position offset between the X-ray irradiation unit and the X-ray detection unit based on the position of the feature point acquired by the optical feature point acquisition unit; and a notification unit that notifies the X-ray irradiation unit based on the position offset acquired by the position offset acquisition unit.

[0010] In the X-ray imaging apparatus of the first aspect described above, as described, it includes: an optical feature point acquisition unit that acquires the position of a feature point by optically detecting the feature point; a position offset acquisition unit that acquires the position offset between the X-ray irradiation unit and the X-ray detection unit; and a notification unit that provides notification based on the position offset. Therefore, by optically acquiring the position of the feature point using the optical feature point acquisition unit, even if electromagnetic waves are emitted from other electronic devices located near the X-ray imaging apparatus, the position of the feature point can be accurately acquired by the optical feature point acquisition unit. Thus, the decrease in accuracy of acquiring the feature point position due to electromagnetic waves emitted from other electronic devices can be suppressed. As a result, an X-ray imaging apparatus capable of suppressing the decrease in detection accuracy due to position offset between the X-ray irradiation unit and the X-ray detection unit caused by surrounding electronic devices can be provided.

[0011] Furthermore, the position offset detection unit for the X-ray imaging apparatus of the second aspect described above includes: an optical feature point acquisition unit that acquires the position of a feature point by optically detecting the feature point; a position offset acquisition unit that acquires the position offset between the X-ray irradiation unit and the X-ray detection unit; and a notification unit that provides notification based on the position offset. Thus, a position offset detection unit for an X-ray imaging apparatus can be provided that, like the X-ray imaging apparatus of the first aspect described above, suppresses the decrease in detection accuracy due to the position offset between the X-ray irradiation unit and the X-ray detection unit caused by surrounding electronic equipment. Attached Figure Description

[0012] Figure 1 This is a block diagram showing the overall structure of an X-ray imaging device according to one embodiment.

[0013] Figure 2 This is a side view showing the overall structure of an X-ray imaging apparatus according to one embodiment.

[0014] Figure 3 This is a side view showing the situation during photography using an X-ray imaging device according to one embodiment.

[0015] Figure 4 This is a schematic diagram illustrating feature points disposed on an X-ray detection unit to explain one embodiment.

[0016] Figure 5 This is a schematic diagram illustrating the structure of a position offset acquisition unit that acquires the position offset between an X-ray irradiation unit and an X-ray detection unit based on feature points in one embodiment.

[0017] Figure 6 This is a schematic diagram illustrating the structure of a position offset acquisition unit that acquires the position of the center of an X-ray irradiation unit according to one embodiment.

[0018] Figure 7 This is a schematic diagram illustrating the structure of a position offset acquisition unit that acquires the position of the center of an X-ray detector in one embodiment.

[0019] Figure 8 This is a schematic diagram showing the axis representing the center of the X-ray irradiation range and the axis representing the center of the X-ray detection unit, displayed in a display section for illustrating one embodiment.

[0020] Figure 9 This is a flowchart illustrating the process by which a position offset acquisition unit acquires the position offset between an X-ray irradiation unit and an X-ray detection unit in one embodiment.

[0021] Figure 10 This is a block diagram showing the overall structure of the X-ray imaging device in the first modified example.

[0022] Figure 11 This is a schematic diagram illustrating the structure of the position offset acquisition unit in the first modified example that acquires the position offset between the X-ray irradiation unit and the X-ray detection unit based on feature points.

[0023] Figure 12 This is a flowchart illustrating the process by which the position offset acquisition unit acquires the position offset between the X-ray irradiation unit and the X-ray detection unit in the first modified example.

[0024] Figure 13 This is a schematic diagram illustrating the feature points set in the X-ray detection unit in the second modified example.

[0025] Figure 14 This is a schematic diagram illustrating the structure of the X-ray detection unit in the third modified example. Detailed Implementation

[0026] (Structure of an X-ray imaging device)

[0027] Reference Figure 1 The structure of an X-ray imaging device 100 according to one embodiment will be described.

[0028] like Figure 1 As shown, the X-ray imaging apparatus 100 of this embodiment includes an X-ray irradiation unit 1, an X-ray detection unit 2, a movement mechanism unit 3, a position offset detection unit 4, a control unit 5, a communication unit 6, a storage unit 7, a display operation unit 8, and a collimator 9. Furthermore, the position offset detection unit 4 is an example of the "position offset detection unit for X-ray imaging apparatus" of the present invention.

[0029] The X-ray irradiation unit 1 is configured to irradiate the subject at a 90° angle (refer to Figure 3 X-ray irradiation unit 1 is configured to irradiate X-rays by applying voltage to an X-ray tube drive unit (not shown).

[0030] An X-ray detection unit 2 is provided during X-ray irradiation, and this X-ray detection unit 2 is configured to detect X-rays irradiated from the X-ray irradiation unit 1. The X-ray detection unit 2 includes, for example, an FPD (flat panel detector). Furthermore, in this embodiment, the X-ray detection unit 2 is configured as a wireless type X-ray detector and can be transported separately from the X-ray imaging device 100. The X-ray detection unit 2 is configured to be stored in the storage unit 3b (see below) when not in use for X-ray imaging. Figure 2 )middle.

[0031] The moving mechanism 3 is configured to move while supporting the X-ray irradiation unit 1. The detailed structure of the moving mechanism 3 will be described later.

[0032] A position offset detection unit 4 is used in an X-ray imaging apparatus 100 comprising an X-ray irradiation unit 1, an X-ray detection unit 2, and a moving mechanism unit 3. The position offset detection unit 4 is configured to detect the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2, and to notify the detected position offset. In this embodiment, as... Figure 1 As shown, the position offset detection unit 4 includes a position offset acquisition unit 4a, an optical feature point acquisition unit 4b, a notification unit 4c, and a unit storage unit 4d.

[0033] The position offset acquisition unit 4a is configured to acquire feature point 11 (see reference) based on the optical feature point acquisition unit 4b. Figure 3 The position offset acquisition unit 4a obtains the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 by using the position of the X-ray irradiation unit 1. The position offset acquisition unit 4a is configured, for example, as a computer including a CPU (Central Processing Unit), ROM (Read Only Memory), and RAM (Random Access Memory). The structure of the position offset acquisition unit 4a for obtaining the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 will be described later.

[0034] An optical feature point acquisition unit 4b is disposed in either the X-ray irradiation unit 1 or the X-ray detection unit 2, and the optical feature point acquisition unit 4b is configured to acquire feature point 11 by optically detecting feature point 11 disposed in the other of the X-ray irradiation unit 1 and the X-ray detection unit 2 (see reference). Figure 3 The position of the feature point 11 is determined by the optical feature point acquisition unit 4b. In this embodiment, the optical feature point acquisition unit 4b includes an imaging unit 13 that acquires position information of the feature point 11 by photographing it. The imaging unit 13 may include, for example, a CCD (Charge Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor. The structure of the optical feature point acquisition unit 4b (imaging unit 13) for acquiring the position of the feature point 11 will be described later.

[0035] The notification unit 4c is configured to send notifications based on the position offset acquired by the position offset acquisition unit 4a. In this embodiment, the notification unit 4c includes a display unit 14, which displays the position offset and an image 20 of the subject 90 captured by the camera unit 13 (see reference). Figure 8 The display unit 14 includes, for example, an LCD monitor.

[0036] The unit storage section 4d includes non-volatile memory. The unit storage section 4d stores the distance 60° between the X-ray irradiation section 1 and the imaging section 13, which will be described later. Figure 6 ).

[0037] The control unit 5 is configured as a computer including a CPU, ROM, and RAM. The control unit 5 is configured to enable the display operation unit 8 to display images obtained during X-ray imaging. Furthermore, the control unit 5 is configured to control various structures of the X-ray imaging apparatus 100 based on operations input through the display operation unit 8.

[0038] The communication unit 6 is configured to communicate with an external network and to acquire imaging command information of the subject 90 from an external source or to send images obtained from X-ray imaging to an external source. Furthermore, the imaging command information is pre-input by, for example, an external server (not shown), and sent from an external source to the X-ray imaging device 100. Moreover, a radiology technician carrying the X-ray imaging device 100, who is patrolling or on standby within the hospital, performs X-ray imaging based on the imaging command information.

[0039] Storage unit 7 includes, for example, non-volatile memory. Furthermore, storage unit 7 stores programs for processing by control unit 5. Additionally, storage unit 7 is configured to store imaging command information acquired through communication unit 6 and images obtained from X-ray imaging.

[0040] The display operation unit 8 is configured, for example, as a touch panel type liquid crystal display. Furthermore, the display operation unit 8 functions as a display unit for displaying images and imaging command information obtained from X-ray photography, and as an input unit for inputting various operations.

[0041] (Device Structure)

[0042] like Figure 2 As shown, the X-ray imaging device 100 of this embodiment is capable of being moved as a whole and is configured to be able to monitor patients (subjects 90, references 90, etc.) in various wards of the hospital during ward rounds. Figure 3 X-ray imaging is performed by moving the X-ray position of the X-ray imaging device 100. The X-ray irradiation unit 1, X-ray detection unit 2, and display operation unit 8 are provided in the moving mechanism unit 3. Additionally, a position offset detection unit 4 and a collimator 9 are provided in the X-ray irradiation unit 1. Furthermore, in this embodiment, the vertical direction is defined as the Z-direction. Within the Z-direction, the upward direction is defined as the Z1 direction, and the downward direction as the Z2 direction.

[0043] The moving mechanism section 3 is configured as a trolley for the X-ray imaging device 100, and a power supply device (not shown), a battery, etc. are installed inside the moving mechanism section 3. In addition, the moving mechanism section 3 is provided with multiple wheels 3a, a storage section 3b, a support column 3c, and an arm section 3d.

[0044] Multiple wheels 3a are provided at the lower part of the moving mechanism section 3. This allows the X-ray imaging device 100 to be moved.

[0045] In addition, the storage section 3b is located at the rear of the moving mechanism section 3. The storage section 3b is configured to store the X-ray detection section 2 in a removable manner.

[0046] Furthermore, a support column 3c is provided in the moving mechanism section 3. Specifically, the support column 3c is installed at the front of the moving mechanism section 3, extending vertically. The support column 3c is hollow inside, and a component capable of raising and lowering the arm section 3d is housed therein. That is, the X-ray irradiation section 1 and the collimator 9 are configured to rise and fall along with the arm section 3d. In addition, the support column 3c is configured to be rotatable in the horizontal direction.

[0047] The arm 3d is installed in a horizontal direction extending from the support column 3c. In addition, the arm 3d is configured to be able to rise and fall relative to the support column 3c, and to be able to extend and retract to change the horizontal position of the X-ray irradiation unit 1.

[0048] like Figure 3 As shown, when photographing the subject at 90°C, from... Figure 2 The X-ray irradiation unit 1 is positioned behind the support column 3c (X2 direction) or in front of the support column 3c (X1 direction). Furthermore, during X-ray irradiation, the X-ray detection unit 2 is positioned between the subject 90 and the top plate 10 on which the subject 90 is placed. That is, during X-ray irradiation (when the subject 90 is being photographed), the person performing the X-ray photography (radiologist) positions the X-ray detection unit 2 on the side of the subject 90 placed on the top plate 10 opposite to the X-ray irradiation unit 1 (the side of the subject 90's back 90a, the position indicated by the dotted line). In this embodiment, the long side direction of the top plate 10 is designated as the X direction. The direction on the side where the subject 90's head is placed is designated as the X1 direction, and the direction on the side where the feet are placed is designated as the X2 direction. The short side direction of the top plate 10, which is orthogonal to the X direction (the left-right direction of the subject 90), is designated as the Y direction. In addition, when the examinee 90 is lying supine, the direction of the examinee 90's right hand is designated as the Y1 direction, and the direction of the examinee's left hand is designated as the Y2 direction. Furthermore, the ceiling 10 is the ceiling of the bed used by the examinee 90 in the ward.

[0049] Here, the X-ray irradiation unit 1 is configured to be freely movable by doctors, radiographers, etc. Additionally, the X-ray detection unit 2 is positioned by radiographers, etc. Therefore, sometimes the relative positions of the X-ray irradiation unit 1 and the X-ray detection unit 2 may shift. When this shift occurs, it may be impossible to accurately image the radiographed area. The positional shift between the X-ray irradiation unit 1 and the X-ray detection unit 2 refers to the optical axis 1a (refer to...) of the X-rays irradiated from the X-ray irradiation unit 1. Figure 6 ) and the center 2c of the X-ray detection unit 2 (refer to Figure 5 The position of the X-ray irradiation unit 1 and the X-ray detection unit 2 has shifted. In addition, the shift in the angle between the X-ray irradiation unit 1 and the X-ray detection unit 2 includes the shift in the rotation direction of the X-ray detection unit 2 within the plane (LM plane).

[0050] Therefore, in this embodiment, the position offset detection unit 4 is configured to acquire the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2, and to notify the position offset through the display unit 14.

[0051] (Configuration of camera unit, feature points, and display unit)

[0052] In this embodiment, such as Figure 3 As shown, the camera unit 13 is provided in the X-ray irradiation unit 1. Furthermore, in this embodiment, the camera unit 13 is configured to capture images of the subject 90 using visible light. Specifically, the camera unit 13 is configured to capture color moving images using visible light.

[0053] In addition, in this embodiment, such as Figure 3 As shown, feature point 11 is set on X-ray detection unit 2.

[0054] In addition, in this embodiment, such as Figure 3 As shown, the display unit 14 is located in the X-ray irradiation unit 1 at a different position than the camera unit 13.

[0055] In this embodiment, the optical feature point acquisition unit 4b (camera unit 13) and the display unit 14 are mountably disposed on the X-ray irradiation unit 1. The camera unit 13 and the display unit 14 are configured to be subsequently mounted on the X-ray irradiation unit 1. Figure 3 In the example shown, the camera unit 13 is disposed on the surface of the X-ray irradiation unit 1 in the Y1 direction. Additionally, the display unit 14 is disposed on the surface of the X-ray irradiation unit 1 in the X1 direction. That is, the position offset detection unit 4 is configured to be mounted on the X-ray irradiation unit 1. In other words, the position offset detection unit 4 is configured to be subsequently mounted on the X-ray irradiation unit 1.

[0056] (Feature point configuration)

[0057] like Figure 4As shown, the feature point 11 includes a marking member 11a. The marking member 11a is disposed on the X-ray detection unit 2. The marking member 11a is separately disposed from the X-ray detection unit 2, and is disposed on the X-ray detection unit 2 by attaching the marking member 11a to the X-ray detection unit 2. Details of the marking member 11a will be described later. In this embodiment, the feature point 11 (marking member 11a) is disposed on the corner 2a of the X-ray detection unit 2. Specifically, the feature point 11 is disposed on the surface of the X-ray detection unit 2 on which the subject 90 is placed. Furthermore, in this embodiment, the feature point 11 (marking member 11a) is also disposed on the corner 2b of the X-ray detection unit 2.

[0058] (area marker)

[0059] In this embodiment, such as Figure 5 As shown, feature point 11 includes planar mark 110a. At least one planar mark 110a is provided in the X-ray detection unit 2. Furthermore, in Figure 5 In the example shown, two planar marks 110a are provided at corners 2a and 2b of the X-ray detection unit 2. The planar marks 110a include at least one of a printed graphic or the outline of the X-ray detection unit 2. In this embodiment, the planar marks 110a are printed graphics. Specifically, the planar marks 110a are graphics printed on the surface of an adhesive plate on the other side of a surface on which adhesive is applied. Figure 5 As shown, the area marker 110a is a rectangular graphic. Information that can be obtained by capturing images using a camera or the like is pre-set in the area marker 110a. The area marker 110a is a so-called AR marker.

[0060] The planar marker 110a includes three or more identification points 12 that are identified by the camera unit 13. Figure 5 In the example shown, the planar marker 110a includes four identification points 12. Furthermore, in Figure 5 In the example shown, each corner of the planar mark 110a is designated as identification point 12. Furthermore, in this embodiment, the long side direction of the X-ray detection unit 2 is designated as the L direction, and the short side direction of the X-ray detection unit 2 is designated as the M direction.

[0061] (Obtaining the positional offset between the X-ray irradiation unit and the X-ray detection unit)

[0062] In this embodiment, the position offset acquisition unit 4a is configured to acquire the center 30a of the irradiation range of the X-rays emitted from the X-ray irradiation unit 1 (see reference). Figure 8The position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 is taken as the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2. Specifically, the position offset acquisition unit 4a acquires the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 by acquiring the position of the center 30a of the X-ray irradiation range in the coordinate system of the image 20 of the subject 90 (hereinafter referred to as the image coordinate system) and the position of the center 2c of the X-ray detection unit 2 in the image coordinate system.

[0063] Here, as Figure 6 As shown, the imaging unit 13 is positioned at a predetermined distance 60 from the X-ray irradiation unit 1. That is, the distance 61 between the optical axis 1a of the X-rays irradiated from the X-ray irradiation unit 1 to the X-ray detection unit 2 and the imaging center 13a of the imaging unit 13 is equal to the distance 60 between the X-ray irradiation unit 1 and the imaging unit 13. Therefore, the position of the center 30a of the X-ray irradiation range in the image coordinate system can be obtained based on the distance 60 between the imaging center 13a and the optical axis 1a of the X-rays. Thus, if the position offset acquisition unit 4a can acquire the position 2c of the center of the X-ray detection unit 2 in the image coordinate system when X-rays are irradiated (during photography), it can acquire the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2. Furthermore, the distance 60 between the X-ray irradiation unit 1 and the imaging unit 13 is acquired in advance and stored in the unit storage unit 4d (see reference). Figure 1 ).

[0064] In this embodiment, the position offset acquisition unit 4a is as follows: Figure 7 As shown, the X-ray irradiation unit 1 and the X-ray detection unit 2 are configured to acquire the positional offset based on the positional information of feature point 11 (area mark 110a). Specifically, the position offset acquisition unit 4a is configured to acquire the position coordinates of each recognition point 12 of the area mark 110a in the in-plane (LM plane) coordinate system (hereinafter referred to as the LM coordinate system) of the X-ray detection unit 2, and acquire the positional information of the area mark 110a in the image 20 by transforming the acquired position coordinates of the area mark 110a in the LM coordinate system into the image coordinate system. In addition, the position coordinates in the LM coordinate system of each recognition point 12 of the area mark 110a are set in advance. Specifically, the position coordinates of each recognition point 12 of the area mark 110a (each recognition point from the first recognition point 12a to the fourth recognition point 12d) are set with the coordinates of the center 2c of the X-ray detection unit 2 as the origin. In addition, the position coordinates in the LM coordinate system include coordinates in the L direction and the M direction.

[0065] like Figure 7As shown, the first identification point 12a is set to (L1, M1) as its position coordinate in the LM coordinate system. The second identification point 12b is set to (L2, M1) as its position coordinate in the LM coordinate system. The third identification point 12c is set to (L1, M2) as its position coordinate in the LM coordinate system. The fourth identification point 12d is set to (L2, M2) as its position coordinate in the LM coordinate system. Furthermore, the center 2c of the X-ray detection unit 2 is set to (0, 0) as its position coordinate in the LM coordinate system.

[0066] Position offset acquisition unit 4a acquires the position offset based on the image 20 (refer to) captured by camera unit 13. Figure 8 The position offset acquisition unit 4a acquires the position coordinates of each identification point 12 of the planar marker 110a in the LM coordinate system. The planar marker 110a includes at least three (four in this embodiment) identification points 12. Therefore, the position offset acquisition unit 4a can acquire the position coordinates of the center 2c of the X-ray detection unit 2 in the LM coordinate system through geometry based on the position coordinates of each identification point 12.

[0067] Here, the L-coordinate values ​​in the LM coordinate system are different for the first identification point 12a and the second identification point 12b, while the M-coordinate values ​​are equal. Furthermore, the L-coordinate values ​​are equal for the first identification point 12a and the third identification point 12c. Therefore, when transforming the position coordinates of the center 2c of the X-ray detection unit 2 in the LM coordinate system to the image coordinate system, the long and short sides of the X-ray detection unit 2 in the LM coordinate system can be transformed to the long and short sides of the X-ray detection unit 2 in the image coordinate system based on the coordinate values ​​of each identification point 12. Thus, the position offset acquisition unit 4a can acquire the position (position coordinates) of the center 30a of the X-ray irradiation range and the position (position coordinates) of the center 2c of the X-ray detection unit 2 in the image coordinate system. Therefore, the position offset acquisition unit 4a can acquire the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2.

[0068] Furthermore, in this embodiment, the position offset acquisition unit 4a is configured to acquire the angular offset based on the position information of the feature point 11 (area marker 110a). That is, in this embodiment, the position offset acquisition unit 4a is configured to acquire the vertical and horizontal position offsets in the image coordinate system, as well as the position offset in the rotation direction within the plane of the image coordinate system.

[0069] (Notification of position offset)

[0070] like Figure 8As shown, in this embodiment, the display unit 14 is configured to display the positional offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 along with the image 20 of the subject 90. Specifically, the display unit 14 is configured to display the axis 30, which represents the center 30a of the irradiation range of the X-rays irradiated from the X-ray irradiation unit 1, and the axis 31, which represents the center 2c of the X-ray detection unit 2, along with the image 20 of the subject 90, thereby displaying the positional and angular offset between the X-ray irradiation unit 1 and the X-ray detection unit 2. Figure 8 In the example shown, the positional offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 is represented by the offset between the center 30a of the X-ray irradiation range and the center 2c of the X-ray detection unit 2. Furthermore, in Figure 8 In the example shown, the angular offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 is represented by the angular offset between axis 30 and axis 31. Furthermore, Figure 8 The angle offset shown is the angle offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 in the image coordinate system (in the plane of image 20).

[0071] (Processing to obtain position offset)

[0072] Next, refer to Figure 9 This section explains how the position offset detection unit 4 acquires the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2.

[0073] In step 101, the camera unit 13 acquires an image 20 of the subject 90. Specifically, the feature points 11 are acquired together with the image 20 of the subject 90.

[0074] In step 102, the position offset acquisition unit 4a acquires the position of the center 2c of the X-ray detection unit 2 based on the image 20. Specifically, the position offset acquisition unit 4a acquires the position information of the center 2c of the X-ray detection unit 2 based on the position information of the identification point 12 of the planar mark 110a.

[0075] In step 103, the position offset acquisition unit 4a acquires the position information of the X-ray irradiation unit 1. Specifically, the position offset acquisition unit 4a obtains the position information from the unit storage unit 4d (refer to...). Figure 1 The position coordinates of the center 30a of the X-ray irradiation range are obtained as the position information of the X-ray irradiation unit 1.

[0076] In step 104, the position offset acquisition unit 4a acquires the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 based on the position information of the center 2c of the X-ray detection unit 2 and the position information of the X-ray irradiation unit 1.

[0077] In step 105, the position offset acquisition unit 4a displays the acquired position offsets of the X-ray irradiation unit 1 and the X-ray detection unit 2 together with the image 20 of the subject 90 on the display unit 14. After that, the processing ends.

[0078] Furthermore, regarding the processing of steps 101 and 102 above, and the processing of step 103, either one can be processed first.

[0079] In this embodiment, the positional offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 is displayed on the display unit 14. Therefore, doctors, radiographers, and the like can align the X-ray irradiation unit 1 and the X-ray detection unit 2 while simultaneously checking the display unit 14. Specifically, the doctor or the like moves the X-ray irradiation unit 1 so that the center 30a of the X-ray irradiation range in the image 20 overlaps with the center 2c of the X-ray detection unit 2. Furthermore, the doctor or the like moves the X-ray irradiation unit 1 so that axis 30 overlaps with axis 31. Thus, the alignment of the X-ray irradiation unit 1 and the X-ray detection unit 2 is completed.

[0080] (Effects of this implementation method)

[0081] In this embodiment, the following effects can be obtained.

[0082] In this embodiment, as described above, the X-ray imaging apparatus 100 includes: an X-ray irradiation unit 1 that irradiates X-rays onto a subject 90; an X-ray detection unit 2 configured during X-ray irradiation and used to detect X-rays irradiated from the X-ray irradiation unit 1; a moving mechanism unit 3 capable of moving while supporting the X-ray irradiation unit 1; an optical feature point acquisition unit 4b disposed on either the X-ray irradiation unit 1 or the X-ray detection unit 2, which acquires the position of a feature point 11 by optically detecting the other feature point 11 disposed on the other of the X-ray irradiation unit 1 and the X-ray detection unit 2; a position offset acquisition unit 4a that acquires the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 based on the position of the feature point 11 acquired by the optical feature point acquisition unit 4b; and a notification unit 4c that provides notification based on the position offset acquired by the position offset acquisition unit 4a.

[0083] Therefore, by optically acquiring the position of feature point 11 using the optical feature point acquisition unit 4b, even if electromagnetic waves are emitted from other electronic devices located near the X-ray imaging device 100, the position of feature point 11 can be accurately acquired by the optical feature point acquisition unit 4b. Thus, the decrease in accuracy of acquiring the position of feature point 11 due to electromagnetic waves emitted from other electronic devices can be suppressed. As a result, an X-ray imaging device 100 can be provided that can suppress the decrease in detection accuracy caused by positional shifts between the X-ray irradiation unit 1 and the X-ray detection unit 2 due to surrounding electronic devices.

[0084] Furthermore, in this embodiment, as described above, an X-ray imaging device position offset detection unit (position offset detection unit 4) is used in the X-ray imaging device 100, which includes: an X-ray irradiation unit 1 that irradiates X-rays onto a subject 90; an X-ray detection unit 2 configured during X-ray irradiation and used to detect X-rays irradiated from the X-ray irradiation unit 1; and a moving mechanism unit 3 capable of moving while supporting the X-ray irradiation unit 1. The motion detection unit includes: an optical feature point acquisition unit 4b, which is disposed on either the X-ray irradiation unit 1 or the X-ray detection unit 2, and acquires the position of the feature point 11 by optically detecting the feature point 11 disposed on the other of the X-ray irradiation unit 1 and the X-ray detection unit 2; a position offset acquisition unit 4a, which acquires the position offset of the relative position between the X-ray irradiation unit 1 and the X-ray detection unit 2 based on the position of the feature point 11 acquired by the optical feature point acquisition unit 4b; and a notification unit 4c, which provides notification based on the position offset acquired by the position offset acquisition unit 4a.

[0085] Therefore, it is possible to provide a position offset detection unit (position offset detection unit 4) for an X-ray imaging device that can suppress the decrease in detection accuracy due to positional offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 caused by the surrounding electronic equipment, just as the X-ray imaging device 100 described above.

[0086] Furthermore, in the above embodiments, by configuring it as follows, the following further effects can be obtained.

[0087] That is, in this embodiment, as described above, feature points 11 are provided in the X-ray detection unit 2, and the optical feature point acquisition unit 4b includes an imaging unit 13 provided in the X-ray irradiation unit 1, which acquires the position information of the feature points 11 by photographing them. Therefore, by using the imaging unit 13 to photograph the feature points 11, the position of the feature points 11 can be easily acquired. As a result, the positional offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 can be easily acquired.

[0088] Furthermore, in this embodiment, as described above, during X-ray irradiation, the X-ray detection unit 2 is positioned between the subject 90 and the top plate 10 for supporting the subject 90, and the feature point 11 is provided at the corner 2a of the X-ray detection unit 2. This allows the feature point 11 to be positioned separately from the center 2c of the X-ray detection unit 2. Consequently, it is possible to prevent the feature point 11 from being covered by the subject 90 when the X-ray detection unit 2 is positioned between the subject 90 and the top plate 10. As a result, it is possible to prevent the feature point 11 from being covered by the subject 90 and thus being unable to be captured by the imaging unit 13.

[0089] Furthermore, in this embodiment, as described above, the feature point 11 includes a planar mark 110a, which includes three or more identification points 12 that are identified by the imaging unit 13. At least one planar mark 110a is provided in the X-ray detection unit 2. Therefore, since the planar mark 110a includes three or more identification points 12, the position of the center 2c of the X-ray detection unit 2 can be easily obtained by photographing the planar mark 110a provided in the X-ray detection unit 2 using the imaging unit 13. As a result, the positional offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 can be easily obtained by photographing the planar mark 110a provided in the X-ray detection unit 2 using the imaging unit 13.

[0090] Furthermore, in this embodiment, as described above, the planar mark 110a includes at least one of the printed pattern and the outline of the X-ray detection unit 2. Here, for example, in a structure using an electromagnetic coil as the feature point 11, a power supply is required to apply current to the electromagnetic coil. Therefore, the number of components increases. However, by using either the printed pattern or the outline of the X-ray detection unit 2 as the feature point 11, the printed pattern can be placed on the X-ray detection unit 2, or the X-ray detection unit 2 itself can be used as the feature point 11. Therefore, by configuring it as described above, for example, compared to a structure using an electromagnetic coil as the feature point 11, the increase in the number of components can be suppressed.

[0091] Furthermore, in this embodiment, as described above, the imaging unit 13 is configured to capture images of the subject 90 using visible light, and the notification unit 4c includes a display unit 14 that displays the positional shift along with the image 20 of the subject 90 captured by the imaging unit 13. Therefore, by displaying the positional shift along with the image 20 of the subject 90 in the display unit 14, the operator can visually perceive the positional shift between the X-ray irradiation unit 1 and the X-ray detection unit 2. As a result, the operator's convenience is improved when adjusting the positional shift, as the positional shift can be visually perceived.

[0092] Furthermore, in this embodiment, as described above, the position offset acquisition unit 4a is configured to acquire the positional and angular offsets between the X-ray irradiation unit 1 and the X-ray detection unit 2 based on positional information. The display unit 14 is configured to display the axis 30, representing the center 30a of the irradiation range of the X-rays irradiated by the X-ray irradiation unit 1, and the axis 31, representing the center 2c of the X-ray detection unit 2, together with the image 20 of the subject 90, thereby displaying the positional and angular offsets between the X-ray irradiation unit 1 and the X-ray detection unit 2. Thus, the image 20 of the subject 90, the axis 30 representing the center 30a of the X-ray irradiation range, and the axis 31 representing the center 2c of the X-ray detection unit 2 can be displayed as guides for aligning the X-ray irradiation unit 1 and the X-ray detection unit 2. Therefore, the operator can use the image 20 of the subject 90, the axis 30 representing the center 30a of the X-ray irradiation range, and the axis 31 representing the center 2c of the X-ray detection unit 2 as guides for aligning the X-ray irradiation unit 1 and the X-ray detection unit 2. As a result, the operator can easily align the X-ray irradiation unit 1 with the X-ray detection unit 2.

[0093] Furthermore, in this embodiment, as described above, the optical feature point acquisition unit 4b and the display unit 14 are mountably disposed on the X-ray irradiation unit 1, and the feature point 11 includes a marking member 11a, which is disposed on the X-ray detection unit 2. Thus, the optical feature point acquisition unit 4b and the display unit 14 are configured to be mounted on the X-ray irradiation unit 1, allowing the position offset detection unit 4 to be installed after an existing X-ray imaging device. Additionally, since the feature point 11 includes the marking member 11a, the feature point 11 can be installed after the X-ray detector of an existing X-ray imaging device. As a result, the position offset detection unit 4 can be installed after an existing X-ray imaging device, making the application of this invention particularly effective for existing X-ray imaging devices.

[0094] (Modified Example)

[0095] Furthermore, it should be considered that the embodiments disclosed herein are illustrative in all respects and not restrictive. The scope of the invention is defined not by the above description of the embodiments but by the claims, and includes all modifications (variations) within the meaning and scope equivalent to the claims.

[0096] For example, in the above embodiment, an example is shown where the feature point 11 (marker member 11a) detected by the optical feature point acquisition unit 4b includes a planar mark 110a, but the present invention is not limited thereto. In the present invention, for example, the feature point 11 (marker member 11a) detected by the optical feature point acquisition unit 4b in the first modified example can be a dot mark 110b (see reference). Figure 11 ).

[0097] like Figure 10 As shown, the X-ray imaging device 200 of the first modified example differs from the X-ray imaging device 100 of the above embodiment in that it has a position offset detection unit 24 instead of a position offset detection unit 4.

[0098] The position offset detection unit 24 differs from the position offset detection unit 4 in the above embodiment in that it has a position offset acquisition unit 24a instead of a position offset acquisition unit 4a.

[0099] Position offset acquisition unit 24a is configured based on dotted marker 110b (see reference). Figure 11 The positional information of the X-ray irradiation unit 1 and the X-ray detection unit 2 is used to obtain the positional offset between them.

[0100] like Figure 11 As shown, feature point 11 includes a dot-shaped mark 110b consisting of an identification point 12 identified by the camera unit 13. For example... Figure 11 As shown, at least three dot-shaped markers 110b are provided in the X-ray detection unit 2. Figure 11 As shown, in the first modified example, three dot-shaped marks 110b are provided in the X-ray detection unit 2. The dot-shaped marks 110b include at least one of a point light source or a retroreflective member that reflects illumination light in the direction of its incidence. Furthermore, the dot-shaped marks 110b can be dots printed on the surface of the X-ray detection unit 2, or a structure in which dot-shaped sheet members are attached to the surface of the X-ray detection unit 2. Figure 11 In the example shown, the dot mark 110b is a point light source. Furthermore, when using a retroreflective element as the dot mark 110b, a light source can be provided in the camera unit 13, and it can be configured to detect light emitted from indoor lighting and reflected by the retroreflective element.

[0101] The dot marker 110b is set at a predetermined position in the X-ray detection unit 2. That is, the dot marker 110b is set in the X-ray detection unit 2 with its position coordinates set to a predetermined position coordinate with the center 2c of the X-ray detection unit 2 as the origin. Therefore, the position offset acquisition unit 24a can acquire the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 by acquiring the position coordinates of the dot marker 110b.

[0102] Next, refer to Figure 12 The process by which the position offset detection unit 24 acquires the position offset between the X-ray irradiation unit 1 and the X-ray detection unit 2 will be explained below. Furthermore, processes that are the same as those performed by the position offset detection unit 4 in the above embodiment will be marked with the same labels, and detailed descriptions will be omitted.

[0103] In step 106, the camera unit 13 acquires the image 20 of the subject 90 along with the feature points 11 (dot marks 110b).

[0104] In step 107, the position offset acquisition unit 24a acquires the position of the center 2c of the X-ray detection unit 2 based on the image 20. Specifically, the position offset acquisition unit 24a acquires the position information of the center 2c of the X-ray detection unit 2 based on the position information of the dotted mark 110b (identification point 12).

[0105] Afterwards, the process proceeds to steps 103 to 105, where the position offset acquisition unit 24a displays the acquired position offsets of the X-ray irradiation unit 1 and the X-ray detection unit 2 together with the image 20 of the subject 90 on the display unit 14. Then, the process ends.

[0106] In the first variation, as described above, the feature point 11 includes a dot-shaped mark 110b consisting of an identification point 12 identified by the imaging unit 13, and at least three dot-shaped marks 110b are provided in the X-ray detection unit 2. Therefore, for example, compared to using an electromagnetic coil as the feature point 11, it is possible to suppress the size of the feature point 11 from becoming too large. As a result, even when the area where the feature point 11 can be arranged in the X-ray detection unit 2 is small, the dot-shaped marks 110b can still be arranged, thus increasing the design freedom of the X-ray detection unit 2.

[0107] Furthermore, in the first variation, as described above, the dot mark 110b includes at least one of a point light source or a retroreflective member that reflects illumination light in the direction of its incidence. Therefore, when the point light source is configured as the dot mark 110b, the position of the dot mark 110b can be easily obtained by detecting the light irradiated from the point light source. Similarly, when the retroreflective member is configured as the dot mark 110b, the position of the dot mark 110b can be easily obtained by detecting the illumination light reflected by the retroreflective member. These results in the ability to easily obtain the position of the X-ray detection unit 2 by configuring either a point light source or a retroreflective member as the dot mark 110b.

[0108] Furthermore, the above embodiment illustrates an example where the feature point 11 is disposed at the corner 2a of the X-ray detection unit 2, but the present invention is not limited thereto. For example, such as Figure 13 As shown in the second modified example, the feature point 11 can be set at a position separate from the corner 2a of the X-ray detection unit 2.

[0109] Specifically, such as Figure 13As shown in the second modified example, the feature point 11 (surface mark 110a) is provided on the X-ray detection unit 2 in a manner that allows it to be moved to a position separated from the corner 2a of the X-ray detection unit 2 by a predetermined distance 50. Figure 13 In the example shown, a planar mark 110a is provided on the support member 15. The support member 15 is rotatably provided on the corner 2a of the X-ray detection unit 2. Specifically, the support member 15 is provided on the corner 2a of the X-ray detection unit 2 in a manner that allows it to rotate in the direction indicated by arrow 40.

[0110] By moving (rotating) the support member 15 in the direction indicated by arrow 40, the feature point 11 (surface mark 110a) can be moved to a position separated from the corner 2a of the X-ray detection unit 2 by a predetermined distance 50.

[0111] In the second variation, as described above, the feature point 11 is positioned on the X-ray detection unit 2 such that it can be moved to a position separated from the corner 2a of the X-ray detection unit 2 by a predetermined distance 50. Therefore, by positioning the feature point 11 at a distance 50 from the corner 2a of the X-ray detection unit 2, it is possible to prevent the feature point 11 from being covered by the subject 90 even when the entire surface of the X-ray detection unit 2 is covered. This further prevents the feature point 11 from being unable to be captured by the imaging unit 13 due to being covered by the subject 90.

[0112] Furthermore, the above embodiment illustrates an example where the planar mark 110a is a printed graphic, but the present invention is not limited thereto. For example, as... Figure 14 As shown in the third variation, the planar mark can be the outline of the X-ray detection unit 2. Furthermore, when the outline of the X-ray detection unit 2 is set as a planar mark, it is preferable to... Figure 14 The corners 2a and 2b of the X-ray detection unit 2 are made to have different shapes, as shown. This allows for the identification of the front and back of the X-ray detection unit 2.

[0113] exist Figure 14 In the example shown, by forming a recess 110c at the corner 2a of the X-ray detection unit 2, the shapes of the corner 2a and corner 2b of the X-ray detection unit 2 can be made different. Furthermore, in the third modified example, each corner of the recess 110c is designated as a recognition point 12.

[0114] Furthermore, the above embodiment illustrates an example where the optical feature point acquisition unit 4b includes an imaging unit 13, but the present invention is not limited thereto. For example, the optical feature point acquisition unit 4b can be configured to: illuminate a laser and detect the laser reflected by an object, and detect the feature point 11 by measuring the time required until the reflected laser is detected. That is, the optical feature point acquisition unit 4b can be composed of a laser illuminating unit, a laser detection unit, and a time measuring unit for measuring the detection time. In other words, the optical feature point acquisition unit 4b can be configured as a so-called LiDAR (Light Detection and Ranging).

[0115] Furthermore, the above embodiment illustrates an example of a structure where the imaging unit 13 captures images of the subject 90 using visible light, but the present invention is not limited to this. For example, the imaging unit may be configured to capture images of the subject 90 using infrared light, which is on the longer wavelength side of a wavelength range adjacent to the visible light region. Alternatively, the imaging unit may be configured to capture images of the subject 90 using ultraviolet light, which is on the shorter wavelength side of a wavelength range adjacent to the visible light region. Furthermore, when the imaging unit captures images of the subject 90 using infrared or ultraviolet light, a light source emitting infrared or ultraviolet light is sufficient.

[0116] Furthermore, the above embodiment illustrates an example where the feature point 11 is located at the corner 2a of the X-ray detection unit 2, but the present invention is not limited thereto. The feature point 11 may be located at a position other than the corner 2a of the X-ray detection unit 2. However, in the case where the feature point 11 is located at a position other than the corner 2a of the X-ray detection unit 2, it is assumed that the subject 90 will cover the feature point 11. Therefore, it is preferable that the feature point 11 is located at the corner 2a of the X-ray detection unit 2.

[0117] Furthermore, the above embodiment illustrates an example of providing two planar marks 110a to the X-ray detection unit 2, but the present invention is not limited thereto. A structure with one planar mark 110a or a structure with three planar marks 110a may be provided. The number of planar marks 110a need only be one or more.

[0118] Furthermore, in the above embodiment, an example was shown where the position offset detection unit 4 is configured to be installed in the X-ray irradiation unit 1, but the present invention is not limited thereto. For example, the position offset detection unit may be fixedly installed in the X-ray irradiation unit 1. That is, the position offset detection unit may be configured as an embedded unit relative to the X-ray irradiation unit 1. In other words, the position offset detection unit may be installed in the X-ray irradiation unit 1 as a so-called built-in unit.

[0119] Furthermore, the above embodiment illustrates an example where the display unit 14 of the position offset detection unit 4 is disposed within the X-ray irradiation unit 1, but the present invention is not limited thereto. For example, the display unit 14 can be separated from the X-ray irradiation unit 1 and disposed in a smartphone, tablet terminal, or the like. In the case where the display unit 14 and the X-ray irradiation unit 1 are disposed separately, the position offset detection unit 4 can be configured to transmit the image 20 to the display unit 14 via a communication unit or the like.

[0120] Furthermore, the above embodiment illustrates an example where the notification unit 4c includes a display unit 14, but the present invention is not limited thereto. For example, the notification unit 4c may be configured to notify the positional shift between the X-ray irradiation unit 1 and the X-ray detection unit 2 via sound. That is, the notification unit 4c may include, for example, a speaker. Alternatively, the notification unit 4c may be configured to notify the positional shift via light. That is, the notification unit may include a light-emitting unit. In the case where the notification unit notifies the positional shift via light, the degree of positional shift can be indicated by different emitted colors.

[0121] Furthermore, the above embodiment illustrates an example where the optical feature point acquisition unit 4b is disposed in the X-ray irradiation unit 1 and the feature point 11 is disposed in the X-ray detection unit 2, but the present invention is not limited thereto. For example, it may be a structure where the feature point 11 is disposed in the X-ray irradiation unit 1 and the optical feature point acquisition unit 4b is disposed in the X-ray detection unit 2.

[0122] Furthermore, the above embodiment illustrates an example of an X-ray imaging device 100 that is moved to the patient's ward during ward rounds to take images, but the present invention is not limited to this. For example, the X-ray imaging device can be installed in an examination room. When the X-ray imaging device is installed in an examination room, the moving mechanism does not need to movably support the entire device; instead, it can be configured to movably support the X-ray irradiation unit.

[0123] Furthermore, in the above embodiment, an example was shown where the position offset acquisition unit 4a acquires the offset in the rotational direction within the plane of the image 20 as the offset of the angle between the X-ray irradiation unit 1 and the X-ray detection unit 2, but the present invention is not limited to this. For example, the position offset acquisition unit may be configured to acquire the offset of the angle about the axis in the X direction and the offset of the angle about the axis in the Y direction. That is, the offset of the angle between the X-ray irradiation unit 1 and the X-ray detection unit 2 may include the offset of the angle about the axis in the Z direction, as well as the offset of the angle about the axis in the X direction and the offset of the angle about the axis in the Y direction.

[0124] [Way]

[0125] Those skilled in the art should understand that the above-described illustrative embodiments are specific examples of the following methods.

[0126] (Project 1)

[0127] The X-ray imaging device has the following features:

[0128] The X-ray irradiation section irradiates the subject with X-rays.

[0129] An X-ray detection unit is configured during X-ray irradiation and is used to detect X-rays irradiated from the X-ray irradiation unit.

[0130] The movable mechanism is capable of moving while supporting the X-ray irradiation unit;

[0131] An optical feature point acquisition unit is disposed on either the X-ray irradiation unit or the X-ray detection unit, and acquires the position of the feature point by optically detecting the feature point disposed on the other of the X-ray irradiation unit and the X-ray detection unit.

[0132] The position offset acquisition unit acquires the position offset between the X-ray irradiation unit and the X-ray detection unit based on the position of the feature point acquired by the optical feature point acquisition unit; and

[0133] The notification unit sends a notification based on the position offset obtained by the position offset acquisition unit.

[0134] (Project 2)

[0135] In the X-ray imaging device described in Project 1,

[0136] The feature points are located in the X-ray detection unit.

[0137] The optical feature point acquisition unit includes a camera unit disposed on the X-ray irradiation unit, and the camera unit acquires the position information of the feature point by photographing the feature point.

[0138] (Project 3)

[0139] In the X-ray imaging device described in Project 2,

[0140] During X-ray irradiation, the X-ray detection unit is positioned between the subject and the top plate used to hold the subject.

[0141] The feature points are located at the corners of the X-ray detection unit.

[0142] (Project 4)

[0143] In the X-ray imaging device described in Project 3,

[0144] The feature point is positioned on the X-ray detection unit in such a way that it can be moved to a position that is separated from the corner of the X-ray detection unit by a predetermined distance.

[0145] (Project 5)

[0146] In any of the X-ray imaging devices described in items 2 to 4,

[0147] The feature points include planar markers, and the planar markers include three or more identification points identified by the camera unit.

[0148] At least one of the planar marks is provided in the X-ray detection unit.

[0149] (Project 6)

[0150] In the X-ray imaging device described in Project 5,

[0151] The planar marking includes at least one of the printed graphic and the shape of the X-ray detection unit.

[0152] (Project 7)

[0153] In any of the X-ray imaging devices described in items 2 to 4,

[0154] The feature points include dot-shaped markers, each consisting of a recognition point identified by the camera unit.

[0155] At least three dot-shaped markers are provided in the X-ray detection unit.

[0156] (Project 8)

[0157] In the X-ray imaging device described in Project 7,

[0158] The dotted marker includes at least one of a point light source and a retroreflective element that reflects illumination light in the direction of its incidence.

[0159] (Project 9)

[0160] In any of the X-ray imaging devices described in items 2 to 4,

[0161] The camera unit is configured to capture images of the subject using visible light.

[0162] The notification unit includes a display unit that displays the positional offset together with an image of the subject captured by the camera unit.

[0163] (Project 10)

[0164] In the X-ray imaging device described in Project 9,

[0165] The position offset acquisition unit is configured to acquire, based on the position information, the positional offset and angular offset between the X-ray irradiation unit and the X-ray detection unit.

[0166] The display unit is configured to display an axis representing the center of the irradiation range of the X-rays irradiated from the X-ray irradiation unit and an axis representing the center of the X-ray detection unit together with the image of the subject, thereby displaying the positional and angular offsets between the X-ray irradiation unit and the X-ray detection unit.

[0167] (Project 11)

[0168] In the X-ray imaging device described in Project 9,

[0169] The optical feature point acquisition unit and the display unit can be mounted on the X-ray irradiation unit.

[0170] The feature points include marker components.

[0171] The marking component is disposed on the X-ray detection unit.

[0172] (Project 12)

[0173] A position offset detection unit for an X-ray imaging device is used in an X-ray imaging device.

[0174] The X-ray imaging device includes: an X-ray irradiation unit that irradiates a subject with X-rays; an X-ray detection unit configured during X-ray irradiation and used to detect X-rays irradiated from the X-ray irradiation unit; and a moving mechanism that is movable while supporting the X-ray irradiation unit.

[0175] The position offset detection unit of the X-ray imaging device includes:

[0176] An optical feature point acquisition unit is disposed on either the X-ray irradiation unit or the X-ray detection unit, and acquires the position of the feature point by optically detecting the feature point disposed on the other of the X-ray irradiation unit and the X-ray detection unit.

[0177] The position offset acquisition unit acquires the position offset between the X-ray irradiation unit and the X-ray detection unit based on the position of the feature point acquired by the optical feature point acquisition unit; and

[0178] The notification unit sends a notification based on the position offset obtained by the position offset acquisition unit.

Claims

1. An X-ray imaging apparatus comprising: an X-ray irradiation section configured to irradiate an X-ray to a subject; an X-ray detection section configured to detect the X-ray irradiated from the X-ray irradiation section when the X-ray is irradiated; a moving mechanism section configured to move while supporting the X-ray irradiation section; an optical feature point acquisition section provided to either one of the X-ray irradiation section and the X-ray detection section, configured to acquire a position of a feature point provided to the other one of the X-ray irradiation section and the X-ray detection section by optically detecting the feature point; a position offset acquisition section configured to acquire a position offset of a relative position of the X-ray irradiation section and the X-ray detection section based on the position of the feature point acquired by the optical feature point acquisition section; and a notification section configured to perform a notification based on the position offset acquired by the position offset acquisition section, wherein the optical feature point acquisition section includes an imaging section provided at a position separated from the X-ray irradiation section by a predetermined distance, the position offset acquisition section is configured to acquire a position of a center of an irradiation range of the X-ray in an image coordinate system that is a coordinate system of an image of the subject and a position of a center of the X-ray detection section in the image coordinate system using information of the predetermined distance, and acquire the position offset of the X-ray irradiation section and the X-ray detection section based on the position of the center of the irradiation range of the X-ray in the image coordinate system and the position of the center of the X-ray detection section in the image coordinate system acquired by the position offset acquisition section.

2. The X-ray imaging apparatus according to claim 1, wherein the feature point is provided to the X-ray detection section, and the imaging section acquires position information of the feature point by imaging the feature point.

3. The X-ray imaging apparatus according to claim 2, wherein the X-ray detection section is configured between the subject and a top plate for placing the subject when the X-ray is irradiated, and the feature point is provided to a corner portion of the X-ray detection section.

4. The X-ray imaging apparatus according to claim 3, wherein the feature point is provided to the X-ray detection section in a manner capable of moving to a position separated from the corner portion of the X-ray detection section by a predetermined distance.

5. The X-ray imaging apparatus according to any one of claims 2 to 4, wherein the feature point includes a planar marker including three or more recognition points recognized by the imaging section, and at least one planar marker is provided to the X-ray detection section.

6. The X-ray imaging apparatus according to claim 5, wherein the planar marker includes at least either one of a printed pattern and an outline of the X-ray detection section.

7. The X-ray imaging apparatus according to any one of claims 2 to 4, wherein the feature point includes a point marker constituted by one recognition point recognized by the imaging section. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ At least three of the point-like markers are provided in the X-ray detection section.

8. The X-ray imaging apparatus according to claim 7, wherein The point-like marker includes at least either one of a point light source and a retro-reflective member that reflects a direction in which illumination light is incident thereon.

9. The X-ray imaging apparatus according to any one of claims 2 to 4, wherein The imaging section is configured to capture the subject by visible light, The notification section includes a display section that displays the positional deviation together with an image of the subject captured by the imaging section.

10. The X-ray imaging apparatus according to claim 9, wherein The positional deviation acquisition section is configured to acquire a positional deviation and an angular deviation between the X-ray irradiation section and the X-ray detection section based on the positional information, The display section is configured to display an axis indicating a center of an irradiation range of X-rays irradiated from the X-ray irradiation section and an axis indicating a center of the X-ray detection section together with the image of the subject, thereby displaying the positional deviation and the angular deviation between the X-ray irradiation section and the X-ray detection section.

11. The X-ray imaging apparatus according to claim 9, wherein The optical feature point acquisition section and the display section are detachably provided to the X-ray irradiation section, The feature point includes a marker member, The marker member is provided to the X-ray detection section.

12. An X-ray imaging apparatus positional deviation detection unit used in an X-ray imaging apparatus that includes an X-ray irradiation section that irradiates X-rays to a subject, an X-ray detection section that is arranged when the X-rays are irradiated, detects the X-rays irradiated from the X-ray irradiation section, and a movement mechanism section that is movable while supporting the X-ray irradiation section, The X-ray imaging apparatus positional deviation detection unit includes: an optical feature point acquisition section that is provided to either one of the X-ray irradiation section and the X-ray detection section, acquires a position of a feature point provided to the other one of the X-ray irradiation section and the X-ray detection section by optically detecting the feature point, a positional deviation acquisition section that acquires a positional deviation of a relative position between the X-ray irradiation section and the X-ray detection section based on the position of the feature point acquired by the optical feature point acquisition section, and a notification section that performs notification based on the positional deviation acquired by the positional deviation acquisition section, wherein the optical feature point acquisition section includes an imaging section that is provided at a position separated from the X-ray irradiation section by a predetermined distance. ​ The position offset acquisition section is configured to acquire, using the information of the prescribed distance, a position of a center of an irradiation range of X-rays in an image coordinate system that is a coordinate system of an image of the subject and a position of a center of the X-ray detection section in the image coordinate system, and acquire the position offset of the X-ray irradiation section and the X-ray detection section based on the position of the center of the irradiation range of X-rays in the image coordinate system and the position of the center of the X-ray detection section in the image coordinate system acquired by the position offset acquisition section.

Images