Radiation imaging device, radiation imaging system, information processing device, information processing system, control method of radiation imaging device, and program

Abstract

To provide a radiation imaging device by using a magnetic sensor that enables acquisition of accurate information on a posture with a simple configuration.SOLUTION: A radiation imaging device is provided with: a magnetic sensor that is fixed to the radiation imaging device and outputs information corresponding to magnetism detected for each of three-axial directions of the radiation imaging device; and calculation means that calculates a correction value for correcting an output of the magnetic sensor by using information output from the magnetic sensor when the radiation imaging device is in a predetermined posture and information corresponding to the predetermined posture.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a radiation imaging device, a radiation imaging system, an information processing device, an information processing system, a control method for a radiation imaging device, and a program.

Background Art

[0002] Radiation imaging devices that convert radiation into digital images are widely used, and techniques for supporting device users by determining the posture of such radiation imaging devices have been disclosed. For example, in the method disclosed in Patent Document 1, the inclination of a radiation image detection device with respect to radiation from a radiation generation device is obtained, and the inclination of the detection surface of the radiation image detection device with respect to the radiation is adjusted. Further, in the method disclosed in Patent Document 1, as means for detecting an angle, an electronic level, a device for measuring levelness, a projection type angle sensor, and the like are cited.

[0003] On the other hand, as a technique for accurately calculating the postures of these devices, which has been applied in recent years in mobile phones, drone (unmanned aircraft) technology, etc., a method using a magnetic sensor has become known. Such a magnetic sensor can also be applied when obtaining the posture of a radiation imaging device.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] A magnetic sensor may have, in addition to an offset component specific to the individual magnetic sensor, an offset component due to magnetization of the surrounding material of the magnetic sensor or an induced magnetic field in the surrounding circuit superimposed on its output. Also, the amount of geomagnetism observed changes depending on the distribution of the magnetic permeability of a building such as an X-ray room where a device including the magnetic sensor is installed. Furthermore, when a magnetic material such as a reinforcing bar in a building where a device including the magnetic sensor is installed becomes magnetized and acquires magnetism, the azimuth of the magnetic north observed is shifted. For these reasons, when attempting to obtain information regarding the posture of a radiation imaging apparatus using a magnetic sensor, it is becoming increasingly difficult to satisfy the accuracy of the posture information required for radiation imaging apparatuses these days.

[0006] The present disclosure is in view of such a situation, and one of its objectives is to provide a radiation imaging apparatus using a magnetic sensor that can obtain highly accurate information regarding posture with a simple configuration.

Means for Solving the Problems

[0007] In order to solve the above problems, a radiation imaging apparatus according to one aspect of the present disclosure includes a magnetic sensor fixed to the radiation imaging apparatus and outputting information corresponding to the magnetism detected in each of the three axial directions of the radiation imaging apparatus, calculating means for calculating a correction value for correcting the output of the magnetic sensor using the information output from the magnetic sensor when the radiation imaging apparatus is in a predetermined posture and the information corresponding to the predetermined posture.

Effects of the Invention

[0008] According to one aspect of the present disclosure, it is possible to provide a radiation imaging apparatus using a magnetic sensor that can obtain highly accurate information regarding posture with a simple configuration.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0010] Hereinafter, with reference to the accompanying drawings, exemplary embodiments for implementing the present disclosure will be described in detail. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential to the invention, and the plurality of features may be arbitrarily combined. Furthermore, the dimensions, materials, shapes, relative positions of the components, etc. described in the following embodiments are arbitrary and can be changed according to the configuration of the device to which the present disclosure is applied or various conditions. Also, in the accompanying drawings, the same reference numerals are used between the drawings in order to indicate the same or functionally similar elements, and duplicate explanations are omitted.

[0011] In the following embodiments and claims, as an example of radiation, a radiation imaging device using X-rays will be described. However, the radiation imaging device according to the present disclosure can include, in addition to X-rays, electromagnetic radiation such as γ-rays, and particle radiation such as α-rays, β-rays, particle beams, proton beams, heavy ion beams, and neutron beams.

[0012] <The First Embodiment> Hereinafter, with reference to FIGS. 1(a) to 5, a radiation imaging apparatus, a radiation imaging system, an information processing apparatus, an information processing system, and a control method for a radiation imaging apparatus according to a first embodiment of the present disclosure will be described. FIG. 1 is a diagram for explaining a schematic configuration of the radiation imaging apparatus according to the present embodiment. Specifically, FIG. 1(a) shows the relationship between the radiation imaging apparatus and a configuration for acquiring signals related to the posture from the radiation imaging apparatus, and FIG. 1(b) schematically shows the internal configuration of the radiation imaging apparatus. Further, FIG. 1(c) shows an outline of a magnetic sensor disposed in the radiation imaging apparatus. FIG. 2 shows a configuration example of the radiation imaging system according to the present embodiment, including a radiation generation apparatus, a device for displaying an image, etc. in the configuration shown in FIG. 1(a).

[0013] (Configuration of the apparatus) The radiation imaging apparatus 200 shown in FIG. 1(a) generates a digital captured image based on radiation information incident by converting radiation such as X-rays into an electrical signal. Further, the radiation imaging apparatus 200 can transmit information regarding the posture of the radiation imaging apparatus 200 in addition to the captured image to the control apparatus 400 via a wireless access point 500. As the control apparatus 400, for example, a PC (Personal Computer) is exemplified. These radiation imaging apparatus 200, access point 500, and control apparatus 400 can constitute a radiation imaging system 1 (see FIG. 2) according to the present embodiment by adding the radiation generation apparatus 700 shown in FIG. 2.

[0014] Note that the information regarding the posture in the present disclosure includes outputs of sensors capable of calculating the posture such as an acceleration sensor, a magnetic sensor (also known as an electronic compass), and an angular velocity sensor (also known as a gyro sensor). Further, the information regarding the posture also includes parameters such as a direction, a movement amount, and a displacement obtained by performing arithmetic processing on the outputs of these sensors. Furthermore, the information regarding the posture in a certain axial direction includes information such as in which direction and at what angle the object is tilted with respect to that axis.

[0015] As shown in FIG. 2, the radiation imaging system 1 includes a radiation imaging device 200 disposed in, for example, an X-ray room that photographs a subject (not shown), an access point 500, a radiation generator 700, and a communication unit 14. Further, the radiation imaging system 1 further includes a control device 400 disposed in an operation room that operates the photographing. Although shown separately here, the control unit 100 of the radiation imaging device 200 and the control device 400 may be integrated.

[0016] The radiation imaging device 200 includes a control unit 100, a radiation detection unit 220, a sensor unit 102, an attitude calculation unit 103, a storage unit 104, a communication unit 105, a power generation unit 106, and a secondary battery 107. The radiation imaging device 200 communicates with the communication unit 14 and is capable of communicating with the control device 400 via the access point 500. In FIGS. 1(a) or 2, a configuration in which the radiation imaging device 200 performs wireless communication is shown, but it can also perform wired communication. In that case, the radiation imaging device 200 is connected to the access point 500 by wire without passing through the communication unit 14.

[0017] As schematically shown in the internal configuration of the radiation imaging device 200 in FIG. 1(b), the radiation imaging device 200 according to the present embodiment has a radiation detection unit 220 composed of a phosphor and a glass substrate. The radiation incident on the radiation detection unit 220 is converted into light by the phosphor and further converted into charge information by a conversion element provided on the glass substrate. The charge information is converted into digital data via a readout circuit including a converter (not shown) and then transmitted to the control unit 100 (electric substrate 215). In the present embodiment, an indirect conversion type radiation detection unit that once converts radiation into light and then converts this into charge is used, but for example, a direct conversion type radiation detection unit that directly converts radiation into charge can also be used.

[0018] For the radiographic image, appropriate image processing is performed by the CPU and programs in the radiographic apparatus 200 and the control apparatus 400, and the processed image is displayed on the display unit 15 by the display control unit 123. Note that the radiographic apparatus 200 in the present embodiment can also function to capture, image-process, and display a radiographic image using radiation. The programs for executing these functions may be provided in the control unit 100, or may be provided in the control unit 120 of the control apparatus 400.

[0019] An angle measurement unit 211 as the sensor unit 102 and an arithmetic circuit 214 as the attitude calculation unit 103 are mounted on the electric substrate 215. The angle measurement unit 211 includes magnetic sensors Mx, My, Mz arranged in three orthogonal axes (x, y, z directions) shown in FIG. 1(c) and acceleration sensors Ax, Ay, Az arranged coaxially. The angle measurement unit 211 uses these sensors to detect the acceleration (ax, ay, az) and magnetism (mx, my, mz) along each axis. Note that each sensor may be in an independent package, but in the present embodiment, an IC in which these sensors are contained in one package is used. In addition to these two types of sensors, a total of nine-axis sensors including angular velocity sensors Gx, Gy, Gz in the same three-axis directions may also be used.

[0020] The arithmetic circuit 214 constituting the attitude calculation unit 103 can be composed of an FPGA (Field Programmable Gate Array) including a so-called memory. The arithmetic circuit 214 can also constitute an arithmetic unit in conjunction with the program stored in the storage unit 122 of the control apparatus 400. The arithmetic unit can perform operations including correction of the output values from the angle measurement unit 211 in addition to image processing. Further, the electric substrate 215 can transfer, for example, data after image processing to the control apparatus 400 via the access point 500.

[0021] The control unit 100 performs overall control of the entire system of the radiation imaging apparatus 200, such as driving control of the radiation detection unit 220, conversion of digital data obtained by the radiation detection unit 220 into an image and correction processing, and control of the communication unit 105. The control unit 100 is composed of, for example, a circuit board having a CPU (Central Processing Unit), a GPU (Graphical Processing Unit), or an FPGA, etc. Note that the control unit 100 may assume the function of the attitude calculation unit 103, or the functions of the control unit 100 and the attitude calculation unit 103 may be realized in different functional areas of the same unit.

[0022] The storage unit 104 includes a non-volatile memory that can store a control program, image data, control parameters, and operation logs of the radiation imaging apparatus 200. Here, a non-volatile memory is cited as an example of the storage unit 104, but it is not limited thereto, and a volatile memory may also be used.

[0023] The communication unit 105 has a function for communicating with other devices arranged independently of the radiation imaging apparatus 200 via the access point 500. The communication unit 105 can exchange various information with other devices through wired or wireless communication. The power generation unit 106 generates various power voltages and currents required for the operation of the radiation imaging apparatus 200 from the power supplied from the secondary battery 107 and supplies power to each unit. The secondary battery 107 has a function as a power source for operating the above-described units. The secondary battery 107 may be detachable or may be built into the housing of the radiation imaging apparatus 200. For the secondary battery 107, for example, a lithium-ion battery or an electric double layer capacitor, etc. can be used.

[0024] The access point 500 has a switching hub function. In this embodiment, for example, it network-connects the radiation imaging device 200, the control device 400, and the radiation generation device 700. Also, it has a relay function in the exchange of signals related to the control of the timing of radiation exposure and detection, such as transmitting the operation information of the radiation generation device 700 to the radiation imaging device 200.

[0025] The control device 400 includes a control unit 120, a communication unit 121, a storage unit 122, a display control unit 123, and an operation unit 124. The control unit 120 receives the operation information of the operation unit 124 and controls the communication unit 121 to send and receive signals for controlling various displays of the display unit 15 and controlling the radiation imaging device 200. The communication unit 121 has a function for communicating with other devices such as the radiation imaging device 200 via the access point 500. That is, the communication unit 121 can exchange various information such as operation information and captured images with other devices through wired or wireless communication. The display control unit 123 causes the display unit 15 to display, for example, the image information and patient information stored in the storage unit 122.

[0026] The storage unit 122 includes a non-volatile memory that can store the control program of the control device 400, captured image data, control parameters, operation logs, etc. Here, a non-volatile memory is given as an example, but it is not limited thereto, and a volatile memory may also be used. The display unit 15 includes a GUI (Graphical User Interface) for operating the radiation imaging device 200, and the operator can operate the GUI using the operation unit 124. In addition, the display unit 15 can display information such as errors and warnings to the operator and the posture information calculated by the posture calculation unit 103 under the control of the control unit 120.

[0027] The control device 400 has a function of acquiring information indicating the state of the radiation imaging device 200 at a predetermined timing and displaying it on a display unit 15 composed of a display or the like to convey it to the operator. Further, the control device 400 can control the state of the radiation imaging device 200 from the above-described operation room using, for example, the GUI of the display unit 15.

[0028] The radiation generator 700 controls irradiation of radiation from a radiation source (not shown) under preset radiation irradiation conditions. Irradiation of radiation from the radiation source can also be executed by the radiation generator 700 in response to depression of a radiation irradiation switch or an operator's instruction via a GUI using a display or a touch panel.

[0029] As an example of a method for photographing a subject, for example, there is a photographing method in which the radiation generator 700 and the radiation imaging device 200 are synchronized. In this case, input information via a switch or the like is transmitted to the radiation imaging device 200 by the access point 500. Then, the radiation generator 700 irradiates radiation after receiving information permitting irradiation from the radiation imaging device 200. Further, the radiation generator 700 receives information regarding the posture of the radiation imaging device 200 or relative position and angle information with respect to the radiation source from the control device 400 or the radiation imaging device 200. Then, the received information can also be displayed on a display device such as a display or a touch panel, for example, the display unit 15.

[0030] The communication performed mutually between the above-described devices may be communication conforming to communication standards such as RS232C, USB, and Ethernet (registered trademark), or may be communication using a dedicated signal line. Further, this communication may be wired communication or wireless communication.

[0031] Next, the operations of each part when performing imaging using the radiation imaging system 1 will be described. The operator turns on the power of the radiation imaging device 200 to make it in a state where imaging is possible. Subsequently, the operator adjusts the positions of the subject and the irradiation area of the radiation irradiated from the radiation source. For the position adjustment, information on the attitude angle of the radiation imaging device 200 and information on the relative position and angle with respect to the radiation source are used assistively. These pieces of information can be displayed on the display unit 15 by the display control unit 123 in the control device 400.

[0032] The radiation generation device 700 controls the radiation source to irradiate radiation toward the radiation imaging device 200, for example, in response to the pressing of the above-described radiation irradiation switch. The radiation irradiated from the radiation source passes through the subject and then enters the radiation imaging device 200. The radiation imaging device 200 generates image data corresponding to the incident radiation by the control unit 100, and transmits this image data to the control device 400 in the operation room via the access point 500 by the communication unit 105. The control device 400 appropriately performs image processing on the received image data and displays it on the display unit 15. The operator of the radiation imaging system 1 can check the image displayed on the display unit 15 and determine whether re-imaging is necessary or not. Then, when the operator determines that the displayed image is normal, the operator performs imaging preparation for another subject in the same procedure.

[0033] (Calibration operation) Next, with reference to FIGS. 3(a) to 3(c) and FIG. 4, calibration processing for obtaining correction values of magnetic sensors Mx, My, and Mz, which is executed in the posture calculation unit 103 in the present embodiment, will be described. FIGS. 3(a) to 3(c) show a jig 600 for causing the radiation imaging apparatus 200 to assume a predetermined posture and each of three predetermined postures. In FIGS. 3(a) to 3(c), for the sake of explanation, a coordinate system with reference to the radiation imaging apparatus 200 is shown by x, y, and z axes orthogonal to each other. Here, an arrangement in which the radiation irradiation surface of the radiation imaging apparatus 200 is perpendicular to each of the three axes in a three-axis coordinate system orthogonal to each other is illustrated. However, the three postures are not limited to this example, and it is sufficient that the relative positional relationship or the orientation of the radiation irradiation surface is determined in the three postures, and the axes do not have to be orthogonal. Further, FIG. 4 shows a series of processes for actually prompting an operator to assume a predetermined posture with the display unit 15 and executing calibration.

[0034] As shown in each of FIGS. 3(a) to 3(c), the jig 600 can fix the radiation imaging apparatus 200 in a plurality of different postures. When calibration (correction value acquisition processing) is started, the calibration processing is started by the control unit 120 according to the flow shown in FIG. 4.

[0035] When the calibration process is started, the process of step S401 is executed. In step S401, the display control unit 123 causes the display unit 15 to display a prompt for the operator to place the radiation imaging apparatus 200 on the jig 600 according to the example shown in FIG. 3(a), for example. Based on the instruction from the display unit 15, the operator fixes the radiation imaging apparatus 200 on the jig 600 in the posture Ra shown in FIG. 3(a). The control unit 120 determines whether or not the radiation imaging apparatus 200 is in the posture Ra in step S402 based on, for example, a contact sensor provided in the radiation imaging apparatus 200 or the like. Alternatively, the control unit 120 may determine whether or not the radiation imaging apparatus 200 is in the posture Ra using the direction information of the gravity applied to the radiation imaging apparatus 200 obtained using the output of the acceleration sensor provided in the radiation imaging apparatus 200. When it is determined that the radiation imaging apparatus 200 is in the posture Ra, the flow proceeds to step S403.

[0036] In step S403, the angle measurement unit 211 acquires a vector m_a = (mx_a, my_a, mz_a) as the outputs of the magnetic sensors Mx, My, Mz in the posture Ra. Each magnetic sensor detects the magnetism acting in the direction corresponding to the magnetic sensor and outputs information corresponding to this magnetism as a vector. When the vector as the output of the magnetic sensor is acquired, the flow proceeds to step S404.

[0037] In step S404, the display control unit 123 causes the display unit 15 to display a prompt for the operator to place the radiation imaging apparatus 200 on the jig 600 according to the example shown in FIG. 3(b), for example. Based on the instruction from the display unit 15, the operator fixes the radiation imaging apparatus 200 on the jig 600 in the posture Rb shown in FIG. 3(b). The control unit 120 determines whether or not the radiation imaging apparatus 200 is in the posture Rb in step S405 based on, for example, a contact sensor provided in the radiation imaging apparatus 200 or the like. When it is determined that the radiation imaging apparatus 200 is in the posture Rb, the flow proceeds to step S406.

[0038] In step S406, the angle measurement unit 211 acquires a vector m_b = (mx_b, my_b, mz_b) as the outputs of the magnetic sensors Mx, My, and Mz in the posture Rb. Here, the posture shown in Fig. 3(b) is the posture obtained by rotating the posture shown in Fig. 3(a) by -90° with respect to the x-axis shown in the figure and then further rotating it by 90° with respect to the y-axis. The amount of change in the posture is represented as Ratob using a rotation matrix. At this time, when looking at the axis in the figure in the direction of the arrow (from negative to positive), the direction of rotation in the clockwise direction is defined as the positive rotation, and the direction of rotation in the counterclockwise direction is defined as the negative rotation. After the vector is acquired, the flow proceeds to step S407.

[0039] In step S407, the display control unit 123 causes the display unit 15 to display a prompt for the operator to place the radiation imaging device 200 on the jig 600 according to the example shown in Fig. 3(c), for example. Based on the instruction from the display unit 15, the operator fixes the radiation imaging device 200 on the jig 600 in the posture Rc shown in Fig. 3(c). The control unit 120 determines whether the radiation imaging device 200 is in the posture Rc in step S408 based on, for example, a contact sensor provided in the radiation imaging device 200. If it is determined that the device is in the posture Rc, the flow proceeds to step S409.

[0040] In step S409, the angle measurement unit 211 acquires a vector m_c = (mx_c, my_c, mz_c) as the outputs of the magnetic sensors Mx, My, and Mz in the posture Rc. Here, the posture shown in Fig. 3(c) is the posture obtained by rotating the posture shown in Fig. 3(a) by 90° with respect to the y-axis shown in the figure and then further rotating it by -90° with respect to the x-axis. The amount of change in the posture at this time is represented as Ratoc using a rotation matrix. In another expression, the posture shown in Fig. 3(c) is the posture obtained by rotating the posture shown in Fig. 3(b) by 90° with respect to the y-axis and then further rotating it by -90° with respect to the z-axis, and the amount of change in this posture is similarly represented as Rbtoc. After the vector is acquired, the flow proceeds to step S410.

[0041] The direction of the geomagnetism with respect to the angle measurement unit 211 does not change in the Earth coordinate system. On the other hand, in the coordinate system with the housing of the radiation imaging apparatus 200 as a reference, the following relationships hold. Ratob * m_b=m_a Ratoc * m_c=m_a Rbtoc * m_c=m_b Here, * represents the inner product of matrices, m_a, m_b, and m_c represent 1x3 matrices, and Ratob, Ratoc, and Rbtoc represent 3x3 matrices. That is, in the predetermined postures illustrated in FIGS. 3(a) to 3(c), the magnetism output by the magnetic sensor or the information regarding the postures corresponding to these postures obtained based on the magnetism always satisfies the above relationships.

[0042] However, in an environment such as indoors or an X-ray room where the radiation imaging apparatus 200 is used, gain errors and offset errors occur in the actual outputs m_a, m_b, and m_c of the magnetic sensor in the x, y, and z-axis directions respectively. For this reason, in each posture, the above equations regarding the magnetism actually output from the magnetic sensors corresponding to each axis do not hold unless correction values for correcting the gain errors and offset errors are inserted for each of the x, y, and z axes.

[0043] Conversely, correction values for the gain errors and offset errors that satisfy the above equations can be calculated from these relational expressions. For this calculation, it is desirable that the respective posture relationships between Ra and Rb, Ra and Rc, and Rb and Rc are in a relationship rotated with respect to any two or more of the three axes of the x, y, and z axes. When vectors that are the outputs of the magnetic sensors are obtained in the postures Ra, Rb, and Rc shown in steps S401, S404, and S407 that satisfy the above conditions, the flow proceeds to step S410.

[0044] In step S410, based on the obtained vector, the arithmetic circuit 214 calculates a correction value for correcting the output of the magnetic sensor. In this way, by using the information regarding the attitude output from the magnetic sensor when the radiation imaging apparatus 200 is in a predetermined attitude, a correction value for correcting the output of the magnetic sensor can be obtained. Then, by using the calculated correction value, even in an environment where the radiation imaging apparatus 200 is generally used, correction of the magnetic sensor with high accuracy can be achieved with a simple configuration.

[0045] In the present disclosure, the programs of the arithmetic circuit 214 and the control device 400 can obtain an arbitrary attitude R of the radiation imaging apparatus 200 by using the outputs mx, my, mz of the magnetic sensor and the outputs ax, ay, az of the acceleration sensor. At this time, by using the correction value obtained by the above-described calibration process to correct the gain error and the offset error, the accuracy of the information regarding the obtained attitude R can be improved. Note that the method of expressing the information regarding the attitude R may be a 3×3 rotation matrix, or an expression using a quaternion or Euler angles. Further, by using the angular velocity sensors Gx, Gy, Gz to acquire the angular velocity sensor outputs gx, gy, gz and using them together with the acceleration sensor output and the angular velocity sensor output, the attitude R can be calculated more accurately. At this time, it is preferable to use a madgwick filter or a Kalman filter as a method of using them together.

[0046] Next, in the radiation imaging apparatus 200 according to the present disclosure, a process of notifying an operator of the correct attitude of the current radiation imaging apparatus 200 using, for example, the display unit 15 will be described. FIG. 5 is a flowchart showing a series of processes from correcting the information regarding the attitude obtained by, for example, the angle measurement unit 211 using the correction value obtained by the above-described process and displaying the result on the display unit 15. When the display process of the information regarding the attitude is started, a series of processes start from step S501.

[0047] In step S501, correction values of each sensor obtained by the process shown in FIG. 4 and stored in the storage unit 104 are acquired by the arithmetic circuit 214. After the acquisition of the correction values, in step S502, the angle measurement unit 211 acquires information regarding the attitude. Here, although it has been described that the processes of step S501 and step S502 are sequentially performed, these processes may be performed simultaneously or in the reverse order. When the correction values and the information regarding the attitude are acquired, in step S503, the arithmetic circuit 214 corrects the information regarding the attitude using the correction values. After the completion of the correction of the information regarding the attitude, the flow proceeds to step S504.

[0048] In step S504, the information regarding the attitude corrected by the arithmetic circuit 214 is transmitted to, for example, the control device 400. In step S505, the information regarding the corrected attitude received by the control unit 120 via the communication unit 121 is displayed on the display unit 15 by the display control unit 123. After the display of the information regarding the corrected attitude, in step S506, if the attitude of the radiation imaging device 200 has been further changed, the flow returns to step S502, and the re-acquisition of the information regarding the attitude, its correction, and the display of the image after the display of the information regarding the correction are performed. If the attitude has not been changed, the display process of the information regarding the attitude is terminated. Here, although it has been described that the information regarding the corrected attitude is to be displayed on the display unit 15, for example, a display unit may be further provided in the radiation imaging device 200, and the information regarding the corrected attitude may be displayed here.

[0049] As described above, according to the present disclosure, based on the sensor output obtained when the radiation imaging device 200 is in a predetermined attitude, a correction value of the information regarding the attitude is obtained. By correcting the output of the magnetic sensor using this correction value, even in an environment where the radiation imaging device is generally used, it is possible to correct the magnetic sensor with a simple configuration and high accuracy, and to obtain an accurate output of the magnetic sensor. Further, by displaying the information regarding the corrected attitude on, for example, the display unit 15, it is possible for the operator to obtain an attitude of the radiation imaging device 200 more suitable for imaging.

[0050] In the present disclosure, the gain error and offset error of the magnetic sensor are calculated and corrected from the change amounts of the three postures of Ra, Rb, and Rc. However, the object of correction is not limited to the output of the magnetic sensor, and the gain error and offset error of the acceleration sensor may be calculated and corrected simultaneously by the same method as the correction of the magnetic sensor. Further, since the gain error and offset error of the magnetic sensor are affected by the magnetic field from the surrounding environment, it is preferable to perform calibration again when the room where the radiation imaging apparatus 200 is installed is moved.

[0051] Also, in the present embodiment, a method of calculating the gain error and offset error of the magnetic sensor from the change amount of the output with respect to the predetermined direction of each magnetic sensor in three predetermined postures has been described. However, when only correcting the gain error or offset error of a specific axis, there are cases where it is possible to correct the output of the magnetic sensor by using the output values obtained from two predetermined postures. On the other hand, depending on the relationship of each of the predetermined postures, such as when the postures of each other are within the same rotation axis, there are cases where posture information and the output of the magnetic sensor regarding four or more predetermined postures are required due to the gain error and offset error.

[0052] The role of the jig 600 in the present disclosure is to fix the radiation imaging apparatus 200 in a plurality of postures with clear mutual relationships. Therefore, if it is possible to satisfy this condition, for example, a robot apparatus whose movement amount can be measured like a C-arm may be used instead of the jig 600. Alternatively, the radiation imaging apparatus 200 may be fixed to the tube head portion of the X-ray source capable of grasping the angle, and calibration may be performed by using this as the jig 600.

[0053] As described above, the radiation imaging apparatus 200 according to the present disclosure includes a magnetic sensor and a calculating means for calculating a correction value for correcting information output from the magnetic sensor. In the present embodiment, the magnetic sensor is fixed to the angle measuring unit 211 provided in the radiation imaging apparatus 200. The magnetic sensor is provided for each of the x, y, and z three-axis directions of the radiation imaging apparatus 200, and each outputs information such as a current value corresponding to the magnetism detected for each axis. The arithmetic circuit 214 that functions as an example of the calculating means calculates a correction value for correcting the output of the magnetic sensor by using the information output from the magnetic sensor when the radiation imaging apparatus 200 is in a predetermined posture and the information corresponding to the predetermined posture.

[0054] Note that the above-described predetermined postures include, for example, three postures in which the relative positional relationship is determined by using the jig 600 as shown in FIGS. 3(a) to 3(c). More specifically, the three postures include three postures in which the radiation irradiation surface of the radiation imaging apparatus 200 is arranged perpendicular to each of the three axes in the coordinate system of the three axes x, y, and z that are perpendicular to each other. Note that it is desirable that the three postures do not include a posture located on the same rotation axis because information on the deviation in each of the three axes cannot be obtained. Further, in the present embodiment, these three postures are obtained by fixing the posture of the radiation imaging apparatus 200 via the jig 600. However, the method of fixing the posture is not limited to this, and it can also be obtained by using, for example, a robot apparatus.

[0055] In this embodiment, the arithmetic circuit 214 is communicably connected via the access point 500 to a display control unit 123 that controls a display unit 15 functioning as display means in the present disclosure. The display control unit 123 functions as an example of display control means in this embodiment, and can sequentially cause the display unit 15 to display the above three postures to be assumed by the operator with the jig 600 for the radiation imaging apparatus 200. The arithmetic circuit 214 can acquire information regarding one of the three postures output from the angle measurement unit 211 each time the radiation imaging apparatus 200 assumes one of the three postures, as shown in the flowchart of FIG. 4, for example. In this embodiment, the display control unit 123 can cause the display unit 15 to display information regarding the posture of the radiation imaging apparatus 200 obtained from the output of the magnetic sensor corrected using the correction value described above.

[0056] The arithmetic circuit 214 can calculate correction values for each of the three-axis directions using the information output in each of the three postures regarding the same direction among the above three-axis directions and the information corresponding to the three postures. In this embodiment, the radiation imaging apparatus 200 may be further provided with at least one of an acceleration sensor and an angular velocity sensor that are provided corresponding to each of the three-axis directions of the radiation imaging apparatus 200 and output information regarding the corresponding axis and are fixed to the radiation imaging apparatus 200. In this case, the arithmetic circuit 214 can also calculate a correction value for correcting the output of the magnetic sensor using the information output from the magnetic sensor and at least one of the acceleration sensor and the angular velocity sensor when the radiation imaging apparatus 200 is in a predetermined posture and the information corresponding to the predetermined posture. Further, in this case, the arithmetic circuit 214 may also calculate correction values for at least one of the acceleration sensor and the angular velocity sensor provided corresponding to each of the three-axis directions.

[0057] According to the present embodiment, it is possible to accurately correct the output of the magnetic sensor mounted in the radiation imaging apparatus by using the information on the posture obtained from the magnetic sensor of the radiation imaging apparatus. Thereby, even in an environment where the radiation imaging apparatus is generally used, it is possible to perform highly accurate correction of the magnetic sensor with a simple configuration.

[0058] <Second Embodiment> In the first embodiment, using the jig 600, the radiation imaging apparatus 200 is set to three predetermined postures with the directions of each of the three axes specified, and from the mutual relationship of the outputs of the magnetic sensor obtained in each posture, the gain error and the offset error are obtained. In contrast, in the present embodiment, for example, the radiation imaging apparatus is photographed by an imaging device such as a camera, or an object such as a radiation generator is photographed by an imaging device provided in the radiation imaging apparatus, thereby appropriately defining the predetermined posture of the first embodiment. Then, from the difference between the output of the magnetic sensor provided in the radiation imaging apparatus at that time and the defined predetermined posture, the gain error and the offset error are obtained. Hereinafter, the radiation imaging apparatus according to the present embodiment will be described with reference to the drawings.

[0059] (Configuration of the Apparatus) Hereinafter, with reference to FIGS. 6(a) to 7, the configuration of the radiation imaging apparatus according to the second embodiment of the present disclosure will be described. Note that the same reference numerals will be used for the components having the same functions and effects as those described in the first embodiment, and the description thereof will be omitted here. As described above, in the present embodiment, instead of using the jig 600 to set the radiation imaging apparatus to a predetermined posture to obtain posture information during calibration, a camera 300 is used to appropriately define a predetermined posture and obtain information on the posture at that time.

[0060] In the apparatus configuration illustrated in Fig. 6(a), a camera 300 capable of photographing the radiation imaging apparatus 200 to obtain information regarding the posture of the radiation imaging apparatus 200 is provided. The camera 300 can photograph, for example, the radiation imaging apparatus 200 that is in a fixed state together with the radiation generation apparatus 700 as a reference for the posture. Based on the information of the reference object, posture information such as how each of the x, y, and z axes of the radiation imaging apparatus 200 is inclined with respect to the gravitational direction can be obtained. The control device 400 acquires the posture information from the camera 300 and the outputs Mx, My, and Mz of the magnetic sensors from the angle measurement unit 211 acquired at the same timing as this posture information via the communication unit 16 and the access point 500. The control device 400 defines the posture of the radiation imaging apparatus 200 specified by the posture information as a predetermined posture. Then, by comparing the outputs Mx, My, and Mz of the magnetic sensors obtained at that time with the x, y, and z axes of the radiation imaging apparatus 200 in the predetermined posture, a gain error and an offset error are obtained.

[0061] Note that the posture information obtained from the camera 300 is a photographed image of the radiation imaging apparatus 200, and the control device 400 calculates the posture of the radiation imaging apparatus 200 with respect to the camera 300 from this photographed image. In the above, it was described that the radiation generation apparatus 700 is photographed together for the assistance of this calculation, but a pattern for recognizing the distance and inclination from the camera may be printed on the surface of the radiation imaging apparatus 200, and the posture information may be obtained from this image. Further, the camera 300 is a detector of electromagnetic waves in a broad sense, and may capture light reflected by the radiation imaging apparatus 200, or may capture light from a light source installed in the radiation imaging apparatus 200. Also, regarding the frequency of the light at that time, it does not matter whether it is visible light or radio waves.

[0062] In the example shown in FIG. 6(a), the camera 300 is provided separately from the radiation imaging device 200. However, the arrangement of the camera 300 is not limited to this example. For example, as illustrated in FIG. 6(b), the camera 300 may be incorporated into the radiation imaging device 200. In this case, the control device 400 acquires, via the access point 500, the captured image of the camera 300 and the outputs Mx, My, Mz of the magnetic sensor from the radiation imaging device 200.

[0063] When the camera 300 is arranged in this way, the control device 400 obtains one reference captured image in advance and captures a characteristic scenery shown in the captured image. The control unit 120 calculates the amount of change in the posture of the camera 300, that is, the radiation imaging device 200, by comparing the characteristic scenery in this reference captured image with that at the time of acquiring an arbitrary captured image. The control device 400 acquires, as information regarding the posture determined based on the posture obtained by adding the amount of change in the posture, information regarding the posture at a predetermined posture of the radiation imaging device 200. The control device 400 defines the posture of the radiation imaging device 200 specified by the information regarding the posture as a predetermined posture. Then, by comparing the outputs Mx, My, Mz of the magnetic sensor obtained at that time with the x, y, z axes of the radiation imaging device 200 in the predetermined posture, the control device 400 obtains the gain error and the offset error.

[0064] As described above, in the present embodiment, the camera 300 only needs to obtain information capable of calculating the amount of change in the posture of the radiation imaging device 200 and identify that the radiation imaging device 200 is in a predetermined posture for calculating the gain error and the offset error when the output of the magnetic sensor is obtained. Therefore, the camera 300 may be in a mode of photographing the outside of the radiation imaging device 200 or in a mode of photographing the radiation imaging device 200 from the outside. Also in the present embodiment, the gain error and the offset error of the magnetic sensor can be calculated from the magnetic sensor outputs Mx, My, Mz acquired when the radiation imaging device 200 is in a predetermined posture, and the position information used for image correction can be corrected.

[0065] Also, in this embodiment, since the imaging by the camera 300 can be continuously performed, the calculation of the gain error and offset error of the magnetic sensor can be continuously performed. At this time, by taking the moving average of each of the gain error and offset error of the magnetic sensor, both the accuracies of the gain error and offset error of the magnetic sensor at the time of position information correction can be improved.

[0066] Furthermore, in this embodiment, it is also possible to correct the captured image by switching between the information on the attitude based on the output of the magnetic sensor corrected by the calculated correction value and the information on the attitude obtained using the camera 300. In such a configuration, normally, the information on the attitude is calculated using the camera 300, but when the accuracy of the information on the attitude decreases, it is possible to switch to the calculation of the information on the attitude using the output from the angle measurement unit 211 which is a magnetic sensor. Such switching of the information on the attitude to be used can be executed, for example, by a switching unit 125 provided in the control device 400 of FIG. 7.

[0067] As a specific example where the accuracy of the information on the attitude obtained using the camera 300 decreases, for example, it is assumed that the radiation imaging device 200 is facing sideways with respect to the camera 300 or the distance is far. In such a case, that is, when the radiation imaging device 200 appears smaller than a predetermined area in the captured image of the camera 300, it is advisable to use the information on the attitude obtained using the output value from the angle measurement unit 211. Alternatively, the information on the attitude may be calculated by combining the calculation result of the information on the attitude by the camera 300 and the information on the attitude based on the output from the angle measurement unit 211 at a predetermined ratio. Note that the ratio in this case can be determined according to, for example, the area of the radiation imaging device 200 in the captured image of the camera 300.

[0068] As described above, in the radiation imaging apparatus 200 according to the present embodiment, the predetermined posture when obtaining the output for correcting the information regarding the position of the magnetic sensor can include the posture calculated using the image obtained by the imaging apparatus exemplified by the camera 300. As exemplified in FIG. 6(a), the camera 300 can be arranged outside the radiation imaging apparatus 200 and calculate a predetermined posture based on the image obtained by photographing the radiation imaging apparatus 200. Further, as exemplified in FIG. 6(b), the camera 300 can be arranged inside the radiation imaging apparatus 200, photograph a predetermined object by the camera 300, acquire a reference image, and calculate and define a predetermined posture using the image.

[0069] Further, in the present embodiment, for example, a switching unit 125 that functions as an example of switching means in the present disclosure can be provided for the control device 400. In the embodiment, an example in which the switching unit 125 is provided in the control device 400 is shown. However, the arrangement of the switching unit is not limited to this example, and for example, it may be provided in the control unit 100 of the radiation imaging device 200. The switching unit 125 can switch information regarding the posture used when operating the radiation imaging device 200. Specifically, the switching unit 125 switches the information regarding the posture to be used between the information acquired using the camera and the information output from the magnetic sensor corrected by the arithmetic circuit 214 using the above-described correction value. At that time, the switching unit 125 may switch the information to be used according to the size of the radiation imaging device 200 imaged by the camera 300 provided outside the radiation imaging device 200. For example, when the size of the imaged radiation imaging device 200 is smaller than a predetermined size, the information regarding the posture output from the magnetic sensor corrected by the arithmetic circuit 214 using the correction value may be used. And when the size of the imaged radiation imaging device 200 is equal to or larger than the predetermined size, the information regarding the posture acquired using the camera 300 may be used. Further, the camera may be provided inside the radiation imaging device 200. In such a case, for example, when the size of a predetermined object serving as a reference for imaging is smaller than a predetermined size, the information regarding the posture output from the magnetic sensor corrected by the arithmetic circuit 214 using the correction value may be used. And when the size of the imaged predetermined object is equal to or larger than the predetermined size, the information regarding the posture acquired using the camera 300 may be used. Furthermore, in the present embodiment, the arithmetic circuit 214 can also update the correction value every time information regarding the posture is calculated from the image obtained by the camera 300.

[0070] Further, the present disclosure can also constitute a radiation imaging system including a radiation imaging device 200, a radiation generation device 700 that irradiates radiation toward the radiation imaging device 200, and a control device 400 that controls these devices.

[0071] Also, in the first embodiment, the arithmetic circuit 214 has been described as a component of the radiation imaging apparatus 200. However, a configuration that acquires information regarding the posture obtained from the angle measurement unit 211 and calculates a correction value for correcting the information regarding the posture can also constitute an information processing apparatus that processes information regarding the posture. The information processing apparatus may be provided as part of the radiation imaging apparatus 200, may be provided in the control apparatus 400 that can acquire information regarding the posture via the access point 500, or the control apparatus 400 itself may function as the information processing apparatus. In this case, the information processing apparatus includes means for acquiring information corresponding to the magnetism detected for each axial direction output by a magnetic sensor fixed corresponding to each of the two axial directions of the radiation imaging apparatus 200. Further, the information processing apparatus has a configuration exemplified by the posture calculation unit 103 or the control unit 120 that calculates a correction value for correcting the output of the magnetic sensor using the information regarding the posture acquired when the radiation imaging apparatus 200 is in the predetermined posture described above and the information corresponding to the predetermined posture. Furthermore, such an information processing apparatus can also constitute an information processing system by being communicably connected to the radiation imaging apparatus 200 via, for example, the access point 500.

[0072] According to the present embodiment, the predetermined posture described in the first embodiment is specified by obtaining the posture information of the radiation imaging apparatus 200 by the camera 300. By comparing the directions of the x, y, and x axes of the radiation imaging apparatus 200 in the specified predetermined posture with the output of the magnetic sensor mounted in the radiation imaging apparatus 200, the position information obtained from the output of the magnetic sensor can be accurately corrected. Therefore, even in an environment where the radiation imaging apparatus is generally used, it is possible to accurately correct the output of the magnetic sensor with a simple configuration.

[0073] <Other Embodiments> The present disclosure can also be realized by supplying a program that implements one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and causing one or more processors in a computer of the system or apparatus to read and execute the program. It can also be realized by a circuit (for example, an ASIC) that implements one or more functions. Further, various recording media such as a flexible disk, an optical disk (for example, CD-ROM, DVD-ROM), a magneto-optical disk, a magnetic tape, a non-volatile memory (for example, USB memory), and a ROM can be used as the recording medium. Also, the program that implements the above-described functions may be downloaded via a network and executed by a computer.

[0074] Moreover, the functions of the above-described embodiments are not limited to being realized only by executing the program code read by the computer. Based on the instructions of the program code, an OS (operating system) or the like running on the computer may perform part or all of the actual processing, and the functions of the above-described embodiments may be realized by such processing.

[0075] Furthermore, the program code read from the recording medium may be written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer. Based on the instructions of the program code, a CPU or the like provided in the function expansion board or the function expansion unit may perform part or all of the actual processing, and the above-described functions may be realized by such processing.

[0076] The above disclosure includes the following configurations, methods, and programs. (Configuration 1) A magnetic sensor fixed to a radiation imaging apparatus and outputting information corresponding to magnetism detected in each of three axial directions of the radiation imaging apparatus; A radiation imaging apparatus comprising: calculation means for calculating a correction value for correcting the output of the magnetic sensor by using the information output from the magnetic sensor when the radiation imaging apparatus is in a predetermined posture and the information corresponding to the predetermined posture. (Configuration 2) The radiation imaging apparatus according to Configuration 1, wherein the predetermined posture includes three postures in which relative positional relationships are defined. (Configuration 3) The radiation imaging apparatus according to Configuration 2, wherein the three postures include three postures arranged such that a radiation irradiation surface in the radiation imaging apparatus is perpendicular to each of the three axes of the coordinate system in a three-axis coordinate system orthogonal to each other. (Configuration 4) The radiation imaging apparatus according to Configuration 2 or 3, wherein the three postures do not include postures located on the same rotation axis. (Configuration 5) The radiation imaging apparatus according to any one of Configurations 2 to 4, wherein the three postures are obtained by fixing the posture of the radiation imaging apparatus via a jig. (Configuration 6) The calculation means is communicably connected to a display control means that causes a display means to sequentially display the three postures assumed by the radiation imaging apparatus by the jig to an operator, The radiation imaging apparatus according to any one of Configurations 2 to 5, wherein the calculation means acquires information regarding the one posture output from the magnetic sensor each time the radiation imaging apparatus assumes one of the three postures. (Configuration 7) The radiation imaging apparatus according to Configuration 6, wherein the display control means causes a display unit to display information regarding the posture of the radiation imaging apparatus obtained from the output of the magnetic sensor corrected using the correction value. (Configuration 8) The radiation imaging apparatus according to Configuration 3, wherein the calculation means calculates a correction value for each of the three-axis directions using information output from the magnetic sensor in each of the three postures regarding the same direction among the three-axis directions and information corresponding to the three postures. (Configuration 9) The radiation imaging apparatus further includes at least one of an acceleration sensor and an angular velocity sensor that are provided corresponding to each of the three-axis directions of the radiation imaging apparatus and output information regarding the corresponding axis and are fixed to the radiation imaging apparatus, The calculation means calculates a correction value for correcting the output of the magnetic sensor using information output from at least one of the magnetic sensor, the acceleration sensor, and the angular velocity sensor and information corresponding to the predetermined posture when the radiation imaging apparatus is in the predetermined posture, according to the radiation imaging apparatus of Configuration 3 or 8. (Configuration 10) Provided corresponding to each of the three axial directions of the radiation imaging apparatus, outputting information about the corresponding axis, and further including at least one of an acceleration sensor and an angular velocity sensor fixed to the radiation imaging apparatus. The calculation means also calculates a correction value for at least one of the acceleration sensor and the angular velocity sensor, according to the radiation imaging apparatus of any one of Configuration 3, 8, and 9. (Configuration 11) The predetermined posture includes a posture calculated using an image obtained by photographing the radiation imaging apparatus with a camera disposed outside the radiation imaging apparatus, or a posture calculated using an image obtained by photographing a predetermined object with a camera disposed inside the radiation imaging apparatus, according to the radiation imaging apparatus of Configuration 1. (Configuration 12) The radiation imaging apparatus of Configuration 11 further includes switching means for switching between information about the posture obtained using the camera and information about the posture output from the magnetic sensor corrected by the calculation means using the correction value as information about the posture of the radiation imaging apparatus used when operating the radiation imaging apparatus. (Configuration 13) When a camera is disposed outside the radiation imaging apparatus and the size of the radiation imaging apparatus imaged by the camera is smaller than a predetermined size, the switching means uses the information output from the magnetic sensor corrected by the calculation means using the correction value, and when the size of the radiation imaging apparatus is equal to or larger than the predetermined size, the switching means uses the information about the posture obtained using the camera. In the case where a camera is disposed inside the radiation imaging apparatus, when the size of a predetermined object imaged by the camera is smaller than a predetermined size, information output from the magnetic sensor corrected by the calculation means using the correction value is used; and when the size of the predetermined object is equal to or larger than the predetermined size, information regarding the posture acquired using the camera is used. The radiation imaging apparatus according to Configuration 12. (Configuration 14) The calculation means updates the correction value every time information regarding the posture calculated using an image obtained by photographing with the camera is acquired. The radiation imaging apparatus according to any one of Configurations 11 to 13. (Configuration 15) A radiation imaging apparatus according to any one of Configurations 1 to 14, a radiation generation apparatus that irradiates radiation toward the radiation imaging apparatus, a control apparatus that controls the radiation imaging apparatus and the radiation generation apparatus, and a radiation imaging system including the same. (Configuration 16) Means for acquiring information corresponding to magnetism detected by a magnetic sensor fixed corresponding to each of the three axial directions of the radiation imaging apparatus in each axial direction, Calculation means for calculating a correction value for correcting the output of the magnetic sensor using the acquired information and information corresponding to the predetermined posture when the radiation imaging apparatus is in a predetermined posture. An information processing apparatus comprising the same. (Configuration 17) The radiation imaging apparatus, the information processing apparatus according to Configuration 16 communicably connected to the radiation imaging apparatus, and an information processing system including the same. (Method 1) Causing a magnetic sensor fixed to a radiation imaging apparatus to output information corresponding to magnetism detected in each of the three axial directions of the radiation imaging apparatus, Calculating a correction value for correcting the output of the magnetic sensor using the information output from the magnetic sensor when the radiation imaging apparatus is in a predetermined posture and information corresponding to the predetermined posture. A control method for a radiation imaging apparatus including (Program 1) A program that, when executed by a processor, causes the processor to execute each step of the control method described in Method 1.

Explanation of Signs

[0077] 200: Radiation imaging apparatus 211: Angle measurement unit 214: Arithmetic circuit 220: Radiation detection unit 300: Camera 400: Control device 500: Access point 600: Fixture

Claims

1. A magnetic sensor fixed to the radiation imaging device and outputting information corresponding to the magnetism detected for each of the three axial directions of the radiation imaging device; A radiation imaging device comprising: calculating means for calculating a correction value for correcting the output of the magnetic sensor by using the information output from the magnetic sensor when the radiation imaging device is in a predetermined posture and the information corresponding to the predetermined posture.

2. The radiation imaging device according to claim 1, wherein the predetermined posture includes three postures in which relative positional relationships are defined.

3. The radiation imaging device according to claim 2, wherein the three postures include three postures arranged such that a radiation irradiation surface in the radiation imaging device is perpendicular to each of the three axes of the coordinate system in a three-axis coordinate system orthogonal to each other.

4. The radiation imaging device according to claim 2, wherein the three postures do not include postures located on the same rotation axis.

5. The radiation imaging device according to claim 2, wherein the three postures are obtained by fixing the posture of the radiation imaging device via a jig.

6. The calculating means is communicably connected to display control means for sequentially displaying, on a display means, the three postures to be taken by the radiation imaging device by the jig to an operator; The radiation imaging device according to claim 2, wherein the calculating means acquires information regarding the one posture output from the magnetic sensor each time the radiation imaging device takes one of the three postures.

7. The radiation imaging device according to claim 6, wherein the display control means causes a display unit to display information regarding the posture of the radiation imaging device obtained from the output of the magnetic sensor corrected by using the correction value.

8. The radiation imaging device according to claim 3, wherein the calculating means calculates a correction value for each of the three axial directions by using the information output from the magnetic sensor in each of the three postures regarding the same direction among the three axial directions and the information corresponding to the three postures.

9. Further comprising at least one of an acceleration sensor and an angular velocity sensor that is provided corresponding to each of the three axial directions of the radiation imaging device and outputs information regarding the corresponding axis and is fixed to the radiation imaging device, The radiation imaging apparatus according to claim 3, wherein the calculating means calculates a correction value for correcting the output of the magnetic sensor by using information output from at least one of the magnetic sensor, the acceleration sensor, and the angular velocity sensor and information corresponding to the predetermined posture when the radiation imaging apparatus is in the predetermined posture.

10. The radiation imaging apparatus further includes at least one of an acceleration sensor and an angular velocity sensor that are provided corresponding to each of the three axial directions of the radiation imaging apparatus and output information about the corresponding axis and are fixed to the radiation imaging apparatus. The radiation imaging apparatus according to claim 3, wherein the calculating means also calculates a correction value for at least one of the acceleration sensor and the angular velocity sensor.

11. The predetermined posture includes a posture calculated by using an image obtained by photographing the radiation imaging apparatus with a camera disposed outside the radiation imaging apparatus, or a posture calculated by using an image obtained by photographing a predetermined object with a camera disposed inside the radiation imaging apparatus. The radiation imaging apparatus according to claim 1.

12. The radiation imaging apparatus according to claim 11, further comprising switching means for switching between information about the posture obtained by using the camera and information about the posture output from the magnetic sensor corrected by the calculating means by using the correction value as information about the posture of the radiation imaging apparatus used when operating the radiation imaging apparatus.

13. When a camera is disposed outside the radiation imaging apparatus and the size of the radiation imaging apparatus imaged by the camera is smaller than a predetermined size, the switching means uses the information output from the magnetic sensor corrected by the calculating means by using the correction value, and when the size of the radiation imaging apparatus is equal to or larger than the predetermined size, the switching means uses the information about the posture obtained by using the camera. When a camera is disposed inside the radiation imaging apparatus and the size of a predetermined object imaged by the camera is smaller than a predetermined size, the switching means uses the information output from the magnetic sensor corrected by the calculating means by using the correction value, and when the size of the predetermined object is equal to or larger than the predetermined size, the switching means uses the information about the posture obtained by using the camera. The radiation imaging apparatus according to claim 12.

14. The radiation imaging apparatus according to claim 11, wherein the calculation means updates the correction value every time information regarding the posture calculated using an image obtained by photographing with the camera is acquired.

15. A radiation imaging apparatus according to any one of claims 1 to 14, A radiation generating apparatus that irradiates radiation toward the radiation imaging apparatus, A control apparatus that controls the radiation imaging apparatus and the radiation generating apparatus, A radiation imaging system comprising the same.

16. Means for acquiring information corresponding to magnetism detected by a magnetic sensor fixed corresponding to each of three axial directions of a radiation imaging apparatus for each axial direction, An information processing apparatus comprising: calculation means for calculating a correction value for correcting an output of the magnetic sensor using the acquired information and information corresponding to the predetermined posture when the radiation imaging apparatus is in a predetermined posture.

17. The radiation imaging apparatus, The information processing apparatus according to claim 16, communicably connected to the radiation imaging apparatus, An information processing system comprising the same.

18. Causing a magnetic sensor fixed to a radiation imaging apparatus to output information corresponding to magnetism detected for each of three axial directions of the radiation imaging apparatus; Calculating a correction value for correcting an output of the magnetic sensor using information output from the magnetic sensor when the radiation imaging apparatus is in a predetermined posture and information corresponding to the predetermined posture; A control method for a radiation imaging apparatus including the same.

19. A program that, when executed by a processor, causes the processor to execute each step of the control method according to claim 18.

Images