Radiographic imaging apparatus, control method thereof, and radiographic imaging system

Abstract

A radiation imaging apparatus, a control method thereof, and a radiation imaging system are disclosed. A radiation imaging apparatus includes a pixel array including a plurality of pixels arranged in a matrix in an imaging region, a plurality of detection pixels arranged in a row direction in a detection pixel group, and a control unit configured to control imaging. A grid having a strip-shaped structure in which a radiation-transmissive layer and a radiation-absorbing layer are alternately arranged in a second direction is provided in the radiation imaging apparatus and can be used. The radiation imaging apparatus further includes a determination unit configured to determine whether the control unit can perform a mode of controlling imaging using a signal from the detection pixel group based on information about an angle between the row direction and the first direction.

Description

Technical Field

[0001] This invention relates to a radiation imaging apparatus, a radiation imaging system, and a control method for the radiation imaging apparatus. Background Technology

[0002] Radiation imaging devices that use sensor panels to detect radiation (e.g., X-rays) are used in industrial, medical, and other fields. In recent years, multifunctional radiation imaging devices have been considered. As one such example, radiation imaging devices with built-in functions for monitoring radiation exposure have been recommended. This function enables the radiation imaging device to detect, for example, the timing of starting radiation exposure from a radiation source, the timing of stopping radiation exposure, and the dose or combined dose of the radiation. By detecting the combined dose of radiation passing through the subject, the radiation imaging device can perform automatic exposure control (AEC) and stop radiation exposure from the radiation source when the detected combined dose reaches an appropriate level. To achieve this function, some known radiation imaging devices include dose detection pixels separate from the pixels used to capture radiation images for detecting the exposure dose.

[0003] Meanwhile, in radiographic imaging, scattered rays are generated when radiation passes through the subject. A grid, shaped like a thin plate, is typically used to remove these scattered rays. The grid is positioned between the subject and the radiographic imaging device, preferably directly in front of the device. The grid has a stripe structure, for example, alternating stripes of radiation-transmitting layer extending in the column direction of the pixels and stripes of radiation-absorbing layer in the row direction of the pixels.

[0004] When the relative positions of the grid and the dose detection pixel are offset from each other, the overlap between the dose detection pixel and the radiation absorption layer can change. Therefore, when the relative positions of the dose detection pixel and the grid are offset from each other, the signal used to detect the radiation dose will change significantly, which will affect the accuracy of the dose detection.

[0005] Japanese Patent Application Publication No. 2014-039792 discusses a radiation imaging apparatus in which the relationship between the pitch of the repeating pattern of the stripe structure of a grating and the pitch of the dose detection pixels in the grating's pitch direction is defined as a desired relationship. According to the discussion in Japanese Patent Application Publication No. 2014-039792, even when the positional relationship between the radiation imaging apparatus and the grating is changed, the output variation of the dose detection pixels can be reduced.

[0006] However, in the radiographic imaging apparatus described in Japanese Patent Application Publication No. 2014-039792, the available spacing of the grid is limited. This restricts the degrees of freedom in selecting the grid for the radiographic imaging apparatus, or in selecting the radiographic imaging apparatus within a radiographic imaging system for mounting the grid.

[0007] Therefore, the present invention aims to provide a radiation imaging system that, even when the radiation imaging device has a built-in dose detection pixel for detecting the radiation dose, can increase the selective freedom relative to the grid and the accuracy of dose detection. Summary of the Invention

[0008] According to one aspect of the invention, a pixel array for a radiation imaging apparatus includes a group of detection pixels in an imaging region, wherein a plurality of pixels in the imaging region for acquiring radiation image data by imaging based on emitted radiation are arranged in a matrix, and a plurality of detection pixels in the detection pixel group for detecting radiation dose are arranged in a row direction, and a control unit configured to control imaging. A grid disposed on one side of the imaging region where radiation is incident can be used, the grid having a stripe structure in which stripe radiation-transmitting layers extending in a first direction and stripe radiation-absorbing layers are alternately arranged in a second direction orthogonal to the first direction. The control unit is configured to execute a mode of controlling imaging using signals from the group of detection pixels. The radiation imaging apparatus further includes a determining unit configured to determine whether the control unit is capable of executing the mode based on information about the angle between the row direction and the first direction.

[0009] Further features of the invention will become clear from the following description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0010] Figure 1 A schematic diagram showing an example configuration of a radiation imaging system is provided.

[0011] Figure 2 A schematic diagram showing an example configuration of a radiation imaging apparatus is provided.

[0012] Figure 3 A schematic diagram illustrating an example of the layout of the area of ​​interest is shown.

[0013] Figure 4 A schematic diagram showing the grid and radiation imaging device mounted on an upright support is shown.

[0014] Figure 5 A schematic diagram showing an example configuration of the control unit is provided.

[0015] Figure 6A flowchart illustrating an example of a control method that includes a deterministic approach is shown. Detailed Implementation

[0016] The embodiments will now be described in detail with reference to the accompanying drawings. Several features are described in the embodiments, but not all of them are essential to the invention. Furthermore, in the drawings, the same or similar configurations are given the same reference numerals and will not be described again thereafter. In the embodiments of the invention, radiation may include beams of energy equal to or greater than such beams, such as beams of energy equal to or greater than X-rays, particle beams, and cosmic rays, in addition to beams formed by particles (including photons) released by radioactive decay, alpha rays, beta rays, and gamma rays.

[0017] Figure 1 A diagram illustrating an example configuration of a radiation imaging system 10 according to an embodiment of the present invention is shown. The radiation imaging system 10 has an imaging component 1 and a control component 2. The imaging component 1 performs radiation irradiation and radiation imaging.

[0018] The imaging component 1 includes a radiation imaging device 100, an upright support 102, a communication cable 107, an access point (AP) 120, a communication control device 123, a radiation control device 124, a radiation source 125, a communication cable 126, and a communication cable 127.

[0019] The control unit 2 includes a control device 110, a radiation irradiation switch 111, an input device 113, a display device 114, a local area network (LAN) 115, and a communication cable 116.

[0020] The radiation imaging apparatus 100 includes a power supply unit 101 comprising a battery, a wired communication unit 103, a wireless communication unit 104, and an attachment detection unit 105 for detecting attachment to an upright support 102. The radiation imaging apparatus 100 performs radiation imaging on the subject 106 by detecting radiation passing through the subject 106 and generating radiation image data.

[0021] Wired communication unit 103 communicates information via a cable connection using a communication standard with a predetermined protocol or a standard such as Ethernet. Wireless communication unit 104, for example, has an antenna and a circuit board including an integrated circuit (IC) for communication, and the circuit board performs wireless communication processing based on a wireless LAN utilization protocol via the antenna. The frequency band, standard, and method of wireless communication in wireless communication unit 104 are not limited, and can use methods such as Near Field Communication (NFC) or... Such as short-range wireless communication methods, or ultra-wideband (UWB) methods. The wireless communication unit 104 may have multiple wireless communication methods, and appropriately selects said methods to perform communication.

[0022] The attachment detection unit 105 can be implemented, for example, by providing a contact-type detection element using a limit switch, a detection element (such as a magnetic, inductive, or capacitive proximity sensor), or by generating an electrical signal to detect attachment upon attachment. The attachment detection unit 105 detects that the radiation imaging device 100 is attached to the upright support 102.

[0023] The upright stand 102 is a stand for mounting the radiation imaging device 100, thereby enabling imaging to obtain a radiation image of a subject in a standing position. The radiation imaging device 100 can be attached to the upright stand 102 and can perform imaging in both attached and detached states.

[0024] Communication cable 107 is used to connect the radiographic imaging device 100 and the communication control device 123. AP 120 communicates wirelessly with the radiographic imaging device 100.

[0025] For example, when the radiographic imaging device 100 is detached from the upright support 102 and used, the access point 120 is used to relay communication between the radiographic imaging device 100, the control device 110, and the radiographic control device 124. The radiographic imaging device 100 or the communication control device 123 may have an access point. In this case, the radiographic imaging device 100, the control device 110, and the radiographic control device 124 can communicate via the access point of the radiographic imaging device 100 or the communication control device 123, without going through the access point 123. The communication control device 123 controls each of the access point 120, the radiographic control device 124, and the control device 110 to enable them to communicate.

[0026] The radiation control device 124 controls the radiation source 125 to emit radiation based on predetermined irradiation conditions. The radiation source 125 is an irradiation unit that uses radiation to irradiate the subject 106 based on the control of the radiation control device 124.

[0027] Communication cable 126 is used to connect AP 120 and communication control device 123. Communication cable 127 is used to connect radiation control device 124 and communication control device 123.

[0028] The control device 110 communicates with the radiation control device 124 and the radiation imaging device 100 via the communication control device 123, and comprehensively controls the radiation imaging system 10.

[0029] The radiation irradiation switch 111 is based on the operation input of operator 112 to determine the timing of radiation irradiation. Input device 113 is a device for inputting instructions from operator 112 and includes various types of input devices such as a keyboard and touch panel. Display device 114 is a device for displaying image-processed radiation image data and a graphical user interface (GUI), and includes a monitor. LAN 115 is the backbone network. Communication cable 116 is a cable for connecting control device 110 and communication control device 123.

[0030] Figure 2 It shows Figure 1 The figure shows an example configuration of the radiation imaging device 100. The radiation imaging device 100, in addition to a power supply unit 101, a wired communication unit 103, a wireless communication unit 104, and an attachment detection unit 105, also includes a pixel array 1100, a drive circuit 221, a readout circuit 222, a signal processing unit 224, a control unit 225, and a power supply circuit 227.

[0031] Pixel array 1100 has multiple pixels arranged in a matrix to acquire radiation image data by imaging emitted radiation and to detect emitted radiation. In the following description, the area in pixel array 1100 where multiple pixels are arranged will be referred to as the imaging area. The multiple pixels include multiple detection pixels 1110 and multiple correction pixels 121, each converting radiation into an electrical signal. Detection pixels 1110 are pixels used to generate radiation images or detect radiation dose. Correction pixels 121 are pixels used to extract dark current components and crosstalk components.

[0032] Each of the plurality of detection pixels 1110 has a conversion element 1120 and a switch 1130. The conversion element 1120 converts radiation into an electrical signal. The switch 1130 is used to connect the column signal line 1160 and the conversion element 1120. The conversion element 1120 has a scintillator that converts radiation into light and a photoelectric conversion element that converts light into an electrical signal, thereby converting radiation into an optical signal. The scintillator is formed in a sheet shape to cover the imaging area and is shared by multiple pixels. The conversion element 1120 may have a conversion element that converts radiation into an electrical signal, and thus directly converts radiation into an electrical signal. For example, a thin-film transistor (TFT) with an active region formed by a semiconductor such as amorphous silicon or polycrystalline silicon (preferably polycrystalline silicon) can be used as the switch 1130.

[0033] Each of the plurality of correction pixels 121 has a conversion element 122 and a switch 1230. The conversion element 122 has a similar configuration to the conversion element 1120 and converts radiation into an electrical signal. The switch 1230 has a similar configuration to the switch 1130 and is used to connect the column signal line 1160 and the conversion element 122. The correction pixel 121 has a similar configuration to the detection pixel 1110. However, the area in the detection pixel 1110 used for detecting radiation is wider than the area in the correction pixel 121. For example, in the case where the correction pixel 121 has a direct-type conversion element 122 that directly converts radiation into an electrical signal, a shielding member made of a heavy metal such as lead is provided on the conversion element 122 of the correction pixel 121 as a shielding member for blocking radiation. In the case where the correction pixel 121 has an indirect-type conversion element 122 that uses a scintillator to convert radiation into light and light into an electrical signal, a shielding film made of a material such as aluminum is provided between the conversion element 122 and the scintillator of the correction pixel 121 as a shielding member. In the correction pixel 121, regardless of whether the conversion element 122 is direct or indirect, the shielding member relative to the imaging area in the plan view is disposed in an area that overlaps at least a portion of the conversion element 122 of the correction pixel 121. The correction pixel 121 blocks radiation and detects dark current components or crosstalk components.

[0034] The detection pixel 1110 outputs radiation dose information or a radiation image based on the radiation. The signal processing unit 224 can generate accurate radiation dose information or an accurate radiation image by subtracting the dark current component or crosstalk component output by the correction pixel 121 from the radiation dose information or radiation image output from the detection pixel 1110.

[0035] Figure 3 This is a diagram illustrating an example arrangement of multiple regions of interest (ROIs) A to E in the imaging region of a radiation imaging apparatus 100. Pixel array 1100 has detection pixels 1110 and correction pixels 121 in ROIs A to E, and also has detection pixels 1110 in areas other than ROIs A to E.

[0036] The radiation imaging device 100 has multiple signal lines 1160, multiple drive lines 1140, and multiple bias lines 1150.

[0037] Each of the multiple column signal lines 1160 is connected to each pixel of each column in the imaging region.

[0038] Each of the multiple driving lines 1140 is connected to the pixels in each row of the imaging region. The driving circuit 221 provides voltages Vg1 to Vgn to the multiple pixels row by row via the multiple driving lines 1140. Here, the orientation of all pixels in the row connected by the driving lines 1140 is called the row direction, and the orientation of all pixels in the column connected by the column signal lines 1160 is called the column direction. The driving circuit 221 thus drives the multiple pixels of the pixel array 1100 row by row.

[0039] The first electrode of the switching element 1120 is connected to the first main electrode of the switch 1130. The second electrode of the switching element 1120 is connected to the bias line 1150. Each bias line 1150 extends in the column direction and is connected to the second electrodes of the plurality of switching elements 1120 arranged in each column in the column direction. The second main electrode of the switch 1130 is connected to the column signal line 1160.

[0040] The first electrode of the switching element 122 is connected to the first main electrode of the switch 1230. The second electrode of the switching element 122 is connected to the bias line 1150. Each bias line 1150 is connected to the second electrodes of a plurality of switching elements 122 arranged in columns in the column direction. The second main electrode of the switch 1230 is connected to the column signal line 1160.

[0041] Power supply circuit 227 provides bias voltage Vs to bias line 1150. Power supply unit 101 includes a battery, a DC-DC converter, etc. Power supply unit 101 includes power supply circuit 227 and generates power supply voltages for analog circuits and for digital circuits for drive control, communication, etc.

[0042] The second main electrode of each of the switches 1130 and 1230 in each column is connected to the column signal line 1160 of the corresponding column. The control electrode of each of the switches 1130 and 1230 in each row is connected to the drive line 1140 of the corresponding row. Multiple column signal lines 1160 are connected to the readout circuit 222.

[0043] The readout circuit 222 includes multiple amplification units 132, a multiplexer 134, and an analog-to-digital converter (hereinafter referred to as an A / D converter) 136. Column signal lines 1160 are connected to each amplification unit 132 (each column signal line 1160 is connected to one amplification unit 132). The amplification unit 132 has, for example, a differential amplifier, and uses the amplifier to amplify the signals on the column signal lines 1160. The multiplexer 134 selects multiple amplification units 132 in a predetermined order and provides the signals from the selected amplification units 132 to the A / D converter 136. The A / D converter 136 converts the provided signals from analog signals to digital signals and outputs a digital signal.

[0044] The signal processing unit 224 outputs dose information or a radiation image of the radiation irradiating the radiation imaging device 100 based on the output signal of the AD converter 136. Specifically, the signal processing unit 224 subtracts the dark current component or crosstalk component generated by the correction pixel 121 from the dose information or radiation image generated by the detection pixel 1110.

[0045] The control unit 225 performs radiation irradiation detection, radiation dose calculation, and overall dose calculation based on information from the signal processing unit 224. The control unit 225, based on information from the signal processing unit 224 and information from... Figure 1 The control unit 225 sends control commands to the control device 110, controlling the drive circuit 221, readout circuit 222, etc. In other words, the control unit 225 can execute a dose control mode that uses dose information of radiation generated by the signal processing unit 224 using signals from the detection pixel group 1110 to control the radiation imaging device 100 to perform imaging. The control unit 225 transmits information from the signal processing unit 224 to the control device 110 via the wired communication unit 103 or the wireless communication unit 104.

[0046] The radiation imaging apparatus 100 also includes an angle detection unit 226. The angle detection unit 226 is designed to detect the angle of the line direction of the radiation imaging apparatus 100 relative to the horizontal direction, and can use an inertial sensor such as an accelerometer. Figure 4 As shown, the grid 301 can be mounted on the upright bracket 102. The grid 301 can be mounted on the upright bracket 102 to be located on the radiation incident side of the radiation imaging device 100. The grid 301 has a stripe structure in which strip-shaped radiation transmission layers and strip-shaped radiation absorption layers extending in a vertical direction (first direction) are alternately arranged in a horizontal direction (second direction) orthogonal to the vertical direction. Simultaneously, the detection pixel group 302, which is to be simultaneously driven to generate dose information, is arranged in the row direction of the radiation imaging device 100. Figure 4 As shown, if the stripe direction of the grid 301 and the array direction of the detection pixel group 302 are substantially orthogonal, the displacement relative to the grid 301 can also ensure the detection accuracy of the dose information.

[0047] However, consider, for example, a portable radiation imaging device 100 capable of wireless communication, having a rectangular irradiation surface that is substantially square in shape, and which can be mounted on an upright stand 102 even when rotated. In this case, the first direction in which the stripes of the grating 301 extend can be substantially parallel to the direction in which the group 302 of the detection pixels 1110 is arranged. In this case, displacement relative to the grating 301 may make it difficult to ensure the accuracy of dose information detection.

[0048] Therefore, the control unit 225 determines whether the dose control mode is executable based on information about the angle between the row direction of the array direction of the detection pixel group 302 and the first direction of the stripe direction of the grid 301. Specifically, the control unit 225 uses the angle θ of the row direction relative to the horizontal direction from the angle detection unit 226 as information about the angle to determine whether the dose control mode is executable. If angle θ is an angle that can be considered substantially orthogonal to the row direction and the first direction, the control unit 225 can determine that the dose control mode is executable. On the other hand, if angle θ is not an angle that can be considered substantially orthogonal (or preferably orthogonal) to the row direction and the first direction, the control unit 225 can determine that the dose control mode is not executable. If the control unit 225 determines that the dose control mode is not executable when executing the dose control mode, the control unit 225 will not control the radiation imaging device 100 to image even if the radiation irradiation switch 111 is pressed. On the other hand, if the control unit 225 determines that the dose control mode is executable when executing the dose control mode, the control unit 225 controls the radiation imaging device 100 to image based on the dose information. When the radiation imaging device 100 is attached to the upright support 102, this control allows the dose control mode to be executed only in the direction where the displacement relative to the grid 301 ensures the accuracy of dose information detection. This relative to the grid 301 thus ensures both the freedom and accuracy of dose selection.

[0049] An example illustrating the use of an accelerometer as angle detection unit 226 will be provided. The sensor axis direction of the accelerometer and the direction orthogonal to the radiation incident surface of the radiation imaging device 100 are defined as the Z-axis, and the column direction of the radiation imaging device 100 is defined as the X-axis and the row direction as the Y-axis. Based on the signal from angle detection unit 226 configured in this way, the angle θ relative to the horizontal row direction can be calculated.

[0050] Figure 5 The illustration is shown. Figure 2 The diagram shows an example configuration of the control unit 225. The control unit 225 may include a drive control unit 400, a central processing unit (CPU) 401, a memory 402, a radiation control unit 403, an image data control unit 404, a communication switching unit 405, and a determination unit 406.

[0051] Drive control unit 400 is based on from Figure 2 Information from the signal processing unit 224 and from Figure 1 The commands from the control device 110 are used to control Figure 2The CPU 401 uses the program and various data stored in the memory 402 to perform overall control of the radiation imaging apparatus 100. The memory 402 stores, for example, the program to be executed by the CPU 401 and various data. The various data include various data obtained through processing by the CPU 401 and radiation image data.

[0052] Radiation control unit 403 is based on from Figure 2 Information from the signal processing unit 224 and information from the drive control unit 400 are used to control the signal processing unit 224 and the drive control unit 400. Figure 1 Communication between the radiation control unit 403 and the radiation control unit 124. The radiation control unit 403 and the radiation control unit 124 communicate with each other about the control information of the radiation control unit 124 (e.g., radiation irradiation start, stop notification, and radiation dose).

[0053] Image data control unit 404 will come from Figure 2 The image data of the signal processing unit 224 is stored in the memory 402.

[0054] The communication switching unit 405 enables communication via the wired communication unit 103 when the communication cable 107 is connected to the radiographic imaging device 100, and enables communication via the wireless communication unit 104 when the communication cable 107 is disconnected from the radiographic imaging device 100.

[0055] The determining unit 406 determines whether a dose control mode is executable based on information about the angle between the row direction of the array direction of the detected pixel group 302 and the first direction of the stripe direction of the grid 301. Specifically, the determining unit 406 uses the angle θ of the row direction relative to the horizontal direction from the angle detection unit 226 as information about the angle to determine whether the dose control mode is executable. If angle θ is an angle that can be considered substantially orthogonal to the first direction, the determining unit 406 can determine that the dose control mode is executable. On the other hand, if angle θ is not an angle that can be considered substantially orthogonal to the first direction, the determining unit 406 can determine that the dose control mode is not executable.

[0056] Next, the operation of the radiographic imaging system 10 during automatic exposure control (AEC) imaging will be described. In AEC imaging, a dose control mode is executed in the radiographic imaging apparatus 100. The operator 112 uses the input device 113 to set subject information such as the identification (ID), name, and date of birth of the subject 106, as well as imaging information such as the imaging site of the subject 106, to the control device 110.

[0057] Operator 112 uses input device 113 to input dose, maximum irradiation time, tube current, tube voltage, area of ​​interest, and site information into control device 110. Control device 110 sends the input radiation irradiation conditions, area of ​​interest, and site information to radiation imaging device 100 and radiation control device 124.

[0058] When imaging preparation is complete, operator 112 presses radiation irradiation switch 111. When radiation irradiation switch 111 is pressed, radiation source 125 irradiates subject 106 with radiation under the control of radiation control device 124. During this process, radiation imaging device 100 communicates with radiation control device 124 to control the start of radiation irradiation. Radiation irradiating subject 106 passes through subject 106 and is incident on radiation imaging device 100. Radiation imaging device 100 drives drive lines 1140 designated for each region of interest using drive circuit 221. Multiple detection pixels 1110 corresponding to the designated drive lines 1140 detect dose (radiation dose) and output dose information. Control unit 225 of radiation imaging device 100 calculates the comprehensive dose, which is the combined value of the doses detected by detection pixels 1110 within a predetermined time period. The control unit 225 of the radiation imaging apparatus 100 calculates a target value for an appropriate dose from the overall dose received from the signal processing unit 224, the site information input by the operator 112, and the imaging conditions, and determines the radiation irradiation stop timing. When the overall dose reaches the target value, the radiation imaging apparatus 100 sends a radiation irradiation stop signal to the radiation control device 124 via communication cable 107, communication control device 123, and communication cable 127. The radiation control device 124 stops the irradiation of the radiation source 125 based on the received radiation irradiation stop signal. After the radiation irradiation stops, the detection pixel 1110 converts the radiation into an electrical signal, and the control unit 225 drives the pixel array 1100 using the drive circuit 221 in response to the radiation irradiation stop signal. The readout circuit 222 generates a radiation image signal based on the signal from the driven pixel array 1100. The AD converter 136 converts the analog radiation image signal into digital radiation image data. Signal processing unit 224 subtracts dark current components or crosstalk components from the radiographic image data and generates corrected radiographic image data. Control unit 225 transmits the generated digital radiographic image data to control unit 110 via communication cable 107, communication control device 123, and communication cable 116.

[0059] The control device 110 performs image processing on the received radiation image data. The control device 110 displays a radiation image based on the image-processed radiation image data on the display device 114. The control device 110 also functions as an image processing device and a display control device.

[0060] This section describes an example of controlling imaging based on a comparison between a composite value of signals from the detection pixel group 302 and a target value used as a threshold; however, the invention is not limited thereto. The control unit 225 can send information about the composite value of signals from the detection pixel group 302 to the radiation control device 124, and the radiation control device 124 can determine the timing for stopping radiation irradiation by the radiation source 125 based on this information. The control unit 225 can control imaging based on the composite value of signals from the detection pixel group 302.

[0061] Figure 6 A flowchart of a control method for a radiation imaging system 10 is shown, and a method for determining whether a dose control mode is feasible will be described with reference to the flowchart.

[0062] In step S501, operator 112 uses input device 113 to input dose, maximum irradiation time, tube current, tube voltage, area of ​​interest, and site information into control device 110. Control device 110 sends the input radiation irradiation conditions, area of ​​interest, and site information to radiation imaging device 100 and radiation control device 124. Control unit 225 begins imaging preparation of radiation imaging device 100 so that imaging can be performed in dose control mode. In response to completion of imaging preparation, control unit 225 sends a signal indicating that imaging preparation is complete to control device 110 and radiation control device 124, and operator 112 presses radiation irradiation switch (SW) 111.

[0063] In step S502, the determination unit 406 of the control unit 225 determines whether the dose control mode is executable. The determination unit 406 can be triggered by a signal indicating that imaging preparation is complete, or by receiving a signal indicating that the radiation irradiation switch 111 is pressed. The determination unit 406 uses the angle θ of the row direction relative to the horizontal direction from the angle detection unit 226 as information about the angle for determination. If angle θ is an angle that can be considered substantially orthogonal to the first direction, the determination unit 406 determines that the dose control mode is executable ("Yes" in step S502), and the process continues to step S503. On the other hand, if angle θ is not an angle that can be considered substantially orthogonal to the first direction, the determination unit 406 determines that the dose control mode is not executable ("No" in step S502), and the process continues to step S504. In the determination, if the absolute value of angle θ, |θ|, is |θ|≤45° or 135°≤|θ|≤225°, the determination unit 406 can determine that angle θ is an angle that can be considered substantially orthogonal to the first direction. This makes it possible to perform the determination with less risk of error and eliminate some movement of the radiation imaging device 100.

[0064] If the determining unit 406 determines that the dose control mode is executable ("Yes" in step S502), the process proceeds to step S503. In step S503, the control unit 225 performs imaging using the radiation imaging device 100 in dose control mode. On the other hand, if the determining unit 406 determines that the dose control mode is not executable ("No" in step S502), the process proceeds to step S504. In step S504, the control unit 225 cancels imaging using the radiation imaging device 100 in dose control mode. The control unit 225 sends a signal indicating cancellation of imaging to the control device 110 and the radiation control device 124.

[0065] In step S505, the control device 110 displays a notification on the display device 114 indicating that the dose control mode is not executable as an error notification. In response to the signal indicating cancellation of imaging, the radiation control device 124 controls the radiation source 125 so that no radiation is emitted even if the radiation irradiation switch 111 is pressed.

[0066] (Other embodiments)

[0067] Embodiments of the present invention can also be implemented by providing a program for implementing one or more functions of the above embodiments to a system or device via a network or storage medium, and causing one or more processors in the system or device's computer to read and execute the processing of the program. Embodiments of the present invention can also be implemented by a circuit (e.g., an application-specific integrated circuit (ASIC)) that implements one or more functions.

[0068] The above embodiments are merely examples of implementing the present invention, and the technical scope of the present invention should not be construed as being limited to these examples. In other words, the present invention can be implemented in various forms without departing from its technical concept or essential characteristics.

[0069] According to embodiments of the present invention, even when the radiation imaging device has built-in dose detection pixels for detecting the radiation dose, the selectivity and accuracy of the detected dose relative to the grid can be ensured.

[0070] Although the invention has been described with reference to exemplary embodiments, it should be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the claims should be given the broadest interpretation to cover all such modifications and equivalent structures and functions.

Claims

1. A radiation imaging device, comprising: A pixel array comprising a group of detection pixels in an imaging region, wherein multiple pixels for obtaining radiation image data by imaging based on emitted radiation are arranged in a matrix in the imaging region, and multiple detection pixels for detecting radiation dose are arranged in a row direction in the group of detection pixels. as well as The control unit, configured to control imaging, A grid disposed on one side of the imaging region where radiation is incident can be used. The grid has a stripe structure in which stripe-shaped radiation transmission layers extending in a first direction and stripe-shaped radiation absorption layers are alternately arranged in a second direction orthogonal to the first direction. The control unit is configured to execute a mode that uses signals from the detected pixel group to control imaging. The radiation imaging apparatus further includes a determining unit configured to determine, based on information about the angle between the row direction and the first direction, whether the control unit can execute the mode, and Wherein, if the determining unit determines that the mode is not executable upon receiving an instruction, even if the control unit receives a signal from a switch indicating that a radiation source configured to emit radiation is emitting radiation, the control unit is configured not to control the imaging.

2. The radiation imaging apparatus according to claim 1, wherein, When the determining unit determines that the mode is executable upon receiving an instruction to emit radiation, the control unit is configured to control the imaging.

3. The radiation imaging apparatus according to claim 1 further includes an angle detection unit configured to detect the angle of the row direction relative to the horizontal direction. in, The control unit includes the determining unit, and The determining unit is configured to use the angle of the row direction relative to the horizontal direction as information for determination.

4. The radiation imaging apparatus according to claim 3, wherein, When the angle of the row direction relative to the horizontal direction is substantially orthogonal to the row direction and the first direction, the determining unit is configured to determine that the mode is executable.

5. The radiation imaging apparatus according to claim 4, wherein, When |θ|≤ 45° or 135°≤|θ|≤225°, where the angle between the row direction and the horizontal direction is θ, the determining unit is configured to determine that the angle between the row direction and the horizontal direction is substantially orthogonal to the row direction and the first direction, and thus the mode is executable.

6. The radiation imaging apparatus of claim 1, further comprising a driving circuit configured to drive the pixel array, in, The control unit is configured to control the drive circuit, and The driving circuit is configured to drive the plurality of pixels row by row.

7. The radiation imaging apparatus according to claim 1, wherein, When the determining unit determines that the mode is executable upon receiving an instruction to emit radiation, the control unit is configured to control the imaging based on a composite value of signals from the detected pixel group.

8. The radiation imaging apparatus according to claim 1, wherein, When the determining unit determines that the mode is executable upon receiving an instruction to emit radiation, the control unit is configured to control the imaging based on a comparison of a combined value of signals from the detected pixel group with a threshold.

9. A radiation imaging system, comprising: The radiation imaging apparatus according to claim 7; as well as A radiation control device configured to control a radiation source. The radiation control device is configured to control the radiation source based on a composite value of signals from the detection pixel group.

10. The radiation imaging system according to claim 9, further comprising an upright support on which the radiation imaging device is mounted. in, In the upright support, the grid is positioned on one side of the radiation incident on the radiation imaging device such that the first direction is parallel to the vertical direction.

11. A radiation imaging system, comprising: The radiation imaging apparatus according to claim 8; as well as A radiation control device configured to control a radiation source. The radiation control device is configured to control the radiation source based on a comparison between a combined value of signals from the detection pixel group and a threshold.

12. A method for controlling a radiation imaging apparatus, the radiation imaging apparatus comprising a pixel array, the pixel array including a group of detection pixels in an imaging region, wherein a plurality of pixels in the imaging region for acquiring radiation image data by imaging based on emitted radiation are arranged in a matrix, and a plurality of detection pixels in the group of detection pixels for detecting radiation dose are arranged in a row direction, wherein, A grid disposed on one side of the imaging region where radiation is incident can be used, the grid having a stripe structure in which stripe-shaped radiation-transmitting layers extending in a first direction and stripe-shaped radiation-absorbing layers are alternately arranged in a second direction orthogonal to the first direction, the method comprising: Control is performed, through which a mode for controlling imaging using signals from the detected pixel group can be executed. Specifically, the feasibility of the mode is determined based on information about the angle between the row direction and the first direction, and If the mode is determined to be unexecutable upon receiving an instruction, the imaging is not controlled even if a signal for issuing an instruction to emit radiation is received from a switch indicating that a radiation source configured to emit radiation is emitting radiation.

Images