Radiation imaging device, control method thereof, and program

Abstract

To enable appropriate radiation imaging by enabling suppression of an artifact that may occur in a radiation image based on an electric signal read from each pixel in a case of radiation imaging of performing automatic exposure control.SOLUTION: A radiation imaging device includes: a pixel array including a plurality of pixels that acquire an electric signal according to an incident radiation ray, the plurality of pixels including a detection pixel that detects a radiation ray dose as an electric signal; and a bias supply circuit 120 for supplying a bias voltage to the plurality of pixels. An output impedance of the bias supply circuit 120 varies depending on whether or not it is a case of radiation imaging of automatic exposure control based on the radiation ray dose detected by the detection pixel.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a radiation imaging apparatus, a control method thereof, and a program. [Background technology]

[0002] Radiation imaging devices using a sensor panel with multiple pixels for detecting radiation such as X-rays are widely used in fields such as industry and medicine. In recent years, studies have been conducted to increase the number of functions of radiation imaging devices, and one such function is the ability to monitor radiation irradiation. This function makes it possible, for example, to detect the timing at which radiation irradiation by a radiation generating device is started or stopped, and to detect the radiation exposure dose or cumulative exposure dose.

[0003] Patent Document 1 describes a radiation imaging device that performs automatic exposure control (AEC) to control radiation irradiation by a radiation generating device in accordance with the radiation dose irradiated to each pixel by the radiation generating device. Patent Document 2 describes a radiation imaging device that performs automatic detection control to detect radiation irradiation and capture images by detecting the amount of change, due to radiation irradiation, in the current flowing in a bias supply circuit that supplies voltage to a pixel array. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-25465 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-268171 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technology described in Patent Document 1 has a problem in that when electrical signals for generating a radiographic image are read from each pixel after automatic exposure control, artifacts occur in the radiographic image due to fluctuations in the bias voltage supplied to each pixel. Furthermore, suppressing fluctuations in the bias voltage may reduce the detection sensitivity in the automatic detection control of radiation exposure as described in Patent Document 2, which may result in a decrease in detection accuracy, such as false detection of radiation exposure.

[0006] An object of the present invention is to enable appropriate radiography by suppressing artifacts that may occur in radiographic images based on electrical signals read from each pixel in radiography using automatic exposure control, and to enable appropriate radiography by suppressing a decrease in detection sensitivity of radiation exposure in radiography using automatic detection control. [Means for solving the problem]

[0007] The radiation imaging device of the present invention comprises a pixel array having a plurality of pixels that acquire electrical signals corresponding to incident radiation, including detection pixels that detect the dose of the radiation as the electrical signal, and a bias supply circuit that supplies a bias voltage to the plurality of pixels, and is characterized in that the output impedance of the bias supply circuit differs depending on whether or not radiation imaging is being performed in which automatic exposure control is performed based on the dose of the radiation detected by the detection pixels. The present invention is also characterized in that it comprises a pixel array having a plurality of pixels that acquire electrical signals corresponding to incident radiation, the plurality of pixels including detection pixels that detect the dose of the radiation as the electrical signal, and a bias supply circuit that supplies a bias voltage to the plurality of pixels, wherein the output impedance of the bias supply circuit differs depending on whether or not radiography is being performed in which automatic detection control is performed to automatically detect the irradiation of the radiation on the pixel array. [Effects of the Invention]

[0008] According to the present invention, it is possible to perform appropriate radiography. Specifically, according to the present invention, in the case of radiography with automatic exposure control, it is possible to suppress artifacts that may occur in a radiographic image based on electrical signals read out from each pixel, thereby enabling appropriate radiography. Furthermore, according to the present invention, in the case of radiography with automatic detection control, it is possible to suppress a decrease in the detection sensitivity of radiation exposure, thereby enabling appropriate radiography. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating an example of a schematic configuration of a radiation imaging system according to a first embodiment. [Figure 2] 1 is a diagram illustrating an example of a schematic configuration of a radiation imaging apparatus according to a first embodiment. [Figure 3] FIG. 3 is a diagram showing an example of a timing chart 300 in the control method of the radiation imaging apparatus according to the first embodiment. [Figure 4] 3 is a diagram showing a first example of the internal configuration of the bias supply circuit shown in FIG. 2 in the radiation imaging apparatus according to the first embodiment. FIG. [Figure 5] 3 is a diagram showing a second example of the internal configuration of the bias supply circuit shown in FIG. 2 in the radiation imaging apparatus according to the first embodiment. FIG. [Figure 6] FIG. 10 is a diagram showing an example of a flowchart of a control method for a radiation imaging system according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, a mode (embodiment) for carrying out the present invention will be described with reference to the drawings. However, the components described in the embodiment described below are merely examples, and the technical scope of the present invention is defined by the claims and is not limited to the description of the embodiment described below.

[0011] (First embodiment) First, the first embodiment will be described.

[0012] 1 is a diagram showing an example of a schematic configuration of a radiation imaging system 10 according to the first embodiment. As shown in Fig. 1, the radiation imaging system 10 is configured to be divided into a radiation room 11 where radiation imaging is performed by irradiating with radiation R, and a control room 12 installed near the radiation room 11.

[0013] The radiation room 11 is equipped with a radiation imaging device 100, an access point (AP) 210, a communication control device 220, a radiation generation device 230, and a radiation source 240 as components of the radiation imaging system 10. The radiation room 11 is further equipped with a radiation imaging device communication cable 201, an AP communication cable 202, a radiation generation device communication cable 203, and a radiation source communication cable 204 as components of the radiation imaging system 10.

[0014] The control room 12 is equipped with a control device 310, a radiation exposure switch 320, an input device 330, a display device 340, an in-hospital LAN 350, and a radiation room communication cable 360 ​​as components of the radiation imaging system .

[0015] The radiation imaging apparatus 100 is an apparatus that performs imaging using radiation R and is configured to be able to communicate with the communication control device 220 and the control device 310. In this embodiment, the radiation imaging apparatus 100 can be configured as an apparatus that can perform both radiation imaging with automatic exposure control (AEC) and radiation imaging without automatic exposure control (AEC). In this case, radiation imaging without automatic exposure control (AEC) includes, for example, radiation imaging with automatic detection control, which is control different from automatic exposure control (AEC), in which the radiation imaging apparatus 100 automatically detects irradiation of radiation R. The radiation imaging apparatus 100 detects incident radiation R (including radiation R that has passed through a subject H in a radiation room 11) and generates radiation image data. As shown in FIG. 1 , the radiation imaging apparatus 100 includes a power supply control unit 101 configured with a battery or the like, a wireless communication unit 102, and a wired communication unit 103. The wireless communication unit 102 is a communication unit that controls wireless communication between the wireless communication unit 102 and the communication control device 220 and the control device 310 via the access point 210 and the AP communication cable 202. The wired communication unit 103 is a communication unit that controls wired communication between the wired communication unit 103 and the communication control device 220 and the control device 310 via the radiation imaging device communication cable 201.

[0016] The radiation imaging device communication cable 201 is a cable for communicatively connecting the radiation imaging device 100 and the communication control device 220. The AP communication cable 202 is a cable for communicatively connecting the access point (AP) 210 and the communication control device 220.

[0017] The access point (AP) 210 performs wireless communication with the radiation imaging apparatus 100 (specifically, the wireless communication unit 102 of the radiation imaging apparatus 100). The communication control device 220 is a device that controls communication between various devices included in the radiation imaging system 10. In the radiation imaging system 10, various setting commands for radiation imaging and radiation image data obtained by radiation imaging are communicated between the radiation imaging apparatus 100 and the control device 310 via the communication control device 220. In the radiation imaging system 10, synchronization signals for radiation imaging and the like are communicated between the radiation imaging apparatus 100 and the radiation generation device 230 via the communication control device 220. At this time, the synchronization signals include a radiation R irradiation enable signal, a radiation R irradiation stop signal, and the like.

[0018] The radiation generating device 230 controls the radiation source 240 to irradiate radiation R based on predetermined radiation irradiation conditions, and causes the radiation source 240 to irradiate the radiation R toward the subject H and the radiation imaging device 100. The radiation generating device communication cable 203 is a cable for communicatively connecting the radiation generating device 230 and the communication control device 220. The radiation source communication cable 204 is a cable for communicatively connecting the radiation source 240 and the radiation generating device 230. The radiation source 240 irradiates radiation R toward the subject H and the radiation imaging device 100 under the control of the radiation generating device 230.

[0019] The control device 310 communicates with the radiation imaging device 100 and the radiation generation device 230 via the radiation room communication cable 360 ​​and the communication control device 220, and comprehensively controls the operation of the radiation imaging system 10. For example, the control device 310 also controls the radiation imaging device 100 that performs imaging using radiation R.

[0020] The radiation irradiation switch 320 is a switch operated by the operator S to input the radiation R irradiation timing.

[0021] The input device 330 is a device that receives operational input from the operator S, and various input devices such as a keyboard and a touch panel are used. Information input through the input device 330 is input to the control device 310.

[0022] The display device 340 is a device that displays various types of information and various types of images under the control of the control device 310. This display device 340 is a device that displays, for example, processed radiographic images and GUI screens, and for example, a display is used.

[0023] The hospital LAN 350 is a backbone network within the hospital.

[0024] The radiation room communication cable 360 ​​is a cable for connecting the control device 310 and the communication control device 220 in the radiation room 11 .

[0025] Next, the operation of the radiation imaging system 10 will be described. First, the operator S inputs and sets subject information such as the ID, name, and date of birth of the subject H, and imaging information such as the body part of the subject H to be imaged, to the control device 310 via the input device 330. The imaging information may include information (command) indicating ON / OFF of the automatic exposure control (AEC) function of the radiation imaging device 100. The imaging information may also include, as parameters, information indicating a selected region in a region of interest (ROI) of the pixel array of the radiation imaging device 100 used in the automatic exposure control (AEC) and information on a threshold value related to the dose of radiation R. The imaging information may also include, as parameters, information indicating a calculation method when using multiple regions of interest (ROI), information indicating a sensitivity correction value, information indicating a density correction value, and information indicating a sensor rotation angle. Note that the subject information and imaging information can be set by the operator S directly inputting them to the input device 330, or can also be set automatically by selecting an examination order received via the in-hospital LAN 350. Furthermore, information on the imaging region of the subject H included in the imaging information can also be set by selecting a preset imaging protocol.

[0026] After setting the subject information and imaging information, the operator S fixes the posture of the subject H and the radiation imaging device 100. When the subject H and the radiation imaging device 100 are ready to be imaged, the operator S presses the radiation irradiation switch 320. When the radiation irradiation switch 320 is pressed, radiation R is irradiated from the radiation source 240 toward the subject H and the radiation imaging device 100.

[0027] The radiation R irradiated to the subject H passes through the subject H and enters the radiation imaging device 100. The radiation imaging device 100 converts the incident radiation R into visible light using a phosphor, then converts it into an electrical signal (radiation image signal) related to a radiation image using a photoelectric conversion element, and generates digital radiation image data by analog-to-digital conversion. The digital radiation image data generated by the radiation imaging device 100 is transmitted from the radiation imaging device 100 to the control device 310. The control device 310 performs image processing on the received digital radiation image data, and displays a radiation image based on the image-processed radiation image data on the display device 340. In this case, the control device 310 functions as an image processing device and a display control device.

[0028] Fig. 2 is a diagram showing an example of a schematic configuration of the radiation imaging apparatus 100 according to the first embodiment. In Fig. 2, the same components as those shown in Fig. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0029] As shown in FIG. 2, the radiation imaging device 100 includes a power supply control unit 101, a radiation detector 110, a bias supply circuit 120, a drive circuit 130, a readout circuit 140, a signal processing unit 150, an imaging device control unit 160, and a communication unit 170.

[0030] The radiation detector 110 has a function of detecting incident radiation R and includes a pixel array having a plurality of pixels 111 to 113 that acquire electrical signals corresponding to the incident radiation R. Specifically, the radiation detector 110 has a plurality of pixels 111 to 113 arranged to form a plurality of rows and a plurality of columns, a plurality of bias lines 114, a plurality of drive lines 115, and a plurality of signal lines 116.

[0031] The multiple bias lines 114 are wirings that are interposed between a bias power supply (a bias power supply 121 in FIG. 4 described later) inside the bias supply circuit 120 and the multiple pixels 111 to 113, and supply a bias voltage Vs from the bias power supply to the multiple pixels 111 to 113.

[0032] The multiple drive lines 115 are arranged corresponding to the multiple rows in the pixel array of the radiation detector 110, and each drive line 115 corresponds to one of the pixel rows. Specifically, one end of each drive line 115 is connected to the drive circuit 130, and the other end opposite to the one end is connected to one of the pixel rows.

[0033] The multiple signal lines 116 are arranged corresponding to the multiple columns in the pixel array of the radiation detector 110, and each signal line 116 corresponds to one of the pixel columns. Specifically, one end of each signal line 116 is connected to the readout circuit 140 (amplifier 141), and the other end opposite to the one end is connected to one of the pixel columns.

[0034] The plurality of pixels in the pixel array of the radiation detector 110 include imaging pixels 111 , detection pixels 112 , and correction pixels 113 .

[0035] The imaging pixels 111 are pixels used to capture (acquire) a radiographic image of the subject H. In this embodiment, the pixels excluding the detection pixels 112 and correction pixels 113 shown in Fig. 2 are imaging pixels 111. The imaging pixels 111 include conversion elements 1111 that convert incident radiation R into electrical signals to detect the radiation R as electrical signals related to a radiographic image, and switch elements 1112 that connect the corresponding signal lines 116 and the conversion elements 1111 to each other.

[0036] The detection pixels 112 are one or more pixels used to detect (monitor) the irradiation dose of radiation R as an electrical signal. The detection pixels 112 are arranged so as to be included in rows and columns of a pixel array configured by a plurality of imaging pixels 111. The detection pixels 112 include a conversion element 1121 that converts radiation R into an electrical signal in order to detect the irradiation dose of radiation R as an electrical signal, and a switch element 1122 that connects the corresponding signal line 116 and the conversion element 1121 to each other.

[0037] The correction pixels 113 are one or more pixels used to correct the exposure dose of radiation R. The correction pixels 113 are arranged so as to be included in rows and columns of a pixel array configured by a plurality of imaging pixels 111. The sensitivity of the correction pixels 113 to radiation R is lower than the sensitivity of the detection pixels 112 to radiation R. The correction pixels 113 include a conversion element 1131 that converts radiation R into an electrical signal to detect an electrical signal for correcting the exposure dose of radiation R, and a switch element 1132 that connects the signal line 116 and the conversion element 1131 to each other.

[0038] 2 may be formed in a first configuration including, for example, a scintillator that converts incident radiation R into light, and a photoelectric conversion element that converts the light generated by the scintillator into an electrical signal. In this case, the scintillator is generally formed in a sheet shape so as to cover the radiation detector 110, and is shared by the multiple pixels 111 to 113. Instead of the first configuration described above, the conversion elements 1111, 1121, and 1131 may be formed in a second configuration that uses conversion elements that directly convert incident radiation R into an electrical signal.

[0039] The switch element 1112, the switch element 1122, and the switch element 1132 shown in FIG. 2 may be formed to include a thin film transistor (TFT) having an active region made of a semiconductor such as amorphous silicon or polycrystalline silicon.

[0040] The conversion element 1111 and the switch element 1112 included in the imaging pixel 111 shown in FIG. 2 will be described below. 2 is connected to a first main electrode of the switch element 1112, and a second electrode of the conversion element 1111 is connected to a bias line 114. One bias line 114 extends in the column direction of the pixel array and is commonly connected to the second electrodes of multiple conversion elements 1111 arranged in the column direction. The bias line 114 receives a bias voltage Vs from a bias supply circuit 120. Second main electrodes of the switch elements 1112 in one or more imaging pixels 111 included in one column of the pixel array are connected to one signal line 116. Furthermore, control electrodes of the switch elements 1112 in one or more imaging pixels 111 included in one row of the pixel array are connected to one drive line 115.

[0041] 2 also have the same pixel configuration as the imaging pixel 111 described above, and are connected to corresponding drive lines 115 and corresponding signal lines 116. In this embodiment, the detection pixel 112 and the correction pixel 113 are exclusively connected to the signal line 116. That is, the correction pixel 113 is not connected to the signal line 116 to which the detection pixel 112 is connected. Furthermore, the detection pixel 112 is not connected to the signal line 116 to which the correction pixel 113 is connected. Note that the imaging pixel 111 may be connected to the same signal line 116 as the detection pixel 112 or the correction pixel 113.

[0042] The bias supply circuit 120 is a circuit for supplying a bias voltage Vs to the bias line 114 based on a control signal from the imaging device control unit 160 .

[0043] The drive circuit 130 is configured to supply drive signals to the pixels to be driven through multiple drive lines 115 based on control signals from the imaging device control unit 160. In this embodiment, the drive signals are signals for turning on switch elements included in the pixels to be driven. The switch elements of each pixel are turned on by a high-level signal and turned off by a low-level signal. Therefore, this high-level signal is referred to as a "drive signal." When a drive signal is supplied to a pixel, the electrical signal accumulated in the conversion element of that pixel becomes readable by the readout circuit 140. Furthermore, when a drive line 115 is connected to at least one of the detection pixel 112 and the correction pixel 113, that drive line 115 is referred to as a "detection drive line 115a." In FIG. 2, the drive lines 115 indicated by Vd1 and Vdm are the detection drive lines 115a.

[0044] The readout circuit 140 is configured to read out electrical signals from the plurality of pixels 111 to 113 through a plurality of signal lines 116. Specifically, the readout circuit 140 includes a plurality of amplifiers 141, a multiplexer 142, and an analog-to-digital converter (hereinafter referred to as "AD converter") 143. Each of the plurality of signal lines 116 is connected to a corresponding amplifier 141 among the plurality of amplifiers 141 included in the readout circuit 140. One signal line 116 corresponds to one amplifier 141. The amplifier 141 amplifies the electrical signal read out through the signal line 116. The multiplexer 142 selects one of the plurality of amplifiers 141 in a predetermined order and supplies the electrical signal from the selected amplifier 141 to the AD converter 143. The AD converter 143 converts the analog electrical signal supplied from the multiplexer 142 into a digital electrical signal and outputs it.

[0045] The electrical signals read out from the imaging pixels 111 by the readout circuit 140 are supplied to the signal processing unit 150, where they are processed, such as by calculation and storage. Specifically, the signal processing unit 150 includes a calculation unit 151 and a storage unit 152. The calculation unit 151 generates a radiographic image based on the electrical signals read out from the imaging pixels 111 and supplies the generated image to the imaging device control unit 160. Furthermore, the electrical signals read out from the detection pixels 112 and the correction pixels 113 by the readout circuit 140 are supplied to the signal processing unit 150, where they are processed by the calculation unit 151 and stored by the storage unit 152. Specifically, the signal processing unit 150 outputs information indicating an exposure dose of radiation R to the radiation imaging device 100, based on the electrical signals read out from the detection pixels 112 and the correction pixels 113. For example, the signal processing unit 150 calculates an exposure dose and / or an integrated exposure dose of radiation R to the radiation imaging device 100.

[0046] The imaging device control unit 160 comprehensively controls the operation of the radiation imaging device 100 and performs various processes. The imaging device control unit 160 controls the power supply control unit 101, the bias supply circuit 120, the drive circuit 130, the readout circuit 140, the signal processing unit 150, and the communication unit 170 based on, for example, information from the signal processing unit 150 or commands and parameters from the control device 310. Here, the commands may include a command indicating ON / OFF of an automatic exposure control (AEC) function, a command indicating an imaging mode for radiography, and the like. In this case, a command indicating OFF of the AEC function is, for example, a command indicating ON of an automatic detection control function, which is a function different from the AEC function and automatically detects irradiation of the pixel array of the radiation detector 110 with radiation R in the radiation imaging device 100. The parameters may also include at least one of a selected region in the region of interest of the pixel array used in the AEC function, a threshold value related to the dose of radiation R, a calculation method when multiple regions of interest are used, a sensitivity correction value, a density correction value, and a sensor rotation angle. Furthermore, the parameters may include at least one of the detection sensitivity and detection threshold of the above-mentioned automatic detection control function. Furthermore, the imaging device control unit 160 controls, for example, the start and end of exposure (accumulation of charges corresponding to the irradiated radiation R by the imaging pixels 111) based on information from the signal processing unit 150. The imaging device control unit 160 may be configured with a general-purpose processing circuit such as a microprocessor, or may be configured with a dedicated processing circuit such as an ASIC (Application Specific Integrated Circuit). Furthermore, when the imaging device control unit 160 is configured with a general-purpose processing circuit, the imaging device control unit 160 may further include a memory.

[0047] The communication unit 170 is controlled by the imaging apparatus control unit 160 and has a function of communicating with the radiation imaging apparatus 100 and external devices (e.g., the communication control device 220 and the control device 310). The communication unit 170 includes the wireless communication unit 102 and wired communication unit 103 shown in FIG. 1. The wireless communication unit 102 controls wireless communication between the communication control device 220 and the control device 310 via the access point 210 and the AP communication cable 202. The wired communication unit 103 controls wired communication between the communication control device 220 and the control device 310 via the radiation imaging apparatus communication cable 201. Here, the wireless communication by the wireless communication unit 102 and the wired communication by the wired communication unit 103 are not limited to a specific method or standard as long as communication can be established in accordance with a desired method or standard. Furthermore, the radiation imaging apparatus 100 may be equipped with a plurality of communication units 170 in order to support a plurality of communication standards.

[0048] Next, problems that arise when performing radiation imaging using an automatic exposure control function (AEC function) in a radiation imaging apparatus will be described.

[0049] The bias line 114, which supplies a bias voltage Vs from the bias supply circuit 120, is connected to each pixel of the pixel array. Therefore, the bias voltage Vs is affected when an electrical signal (such as an image signal) is read from each pixel, and the degree of this influence increases according to the amount of charge in the read electrical signal. During AEC driving, the drive circuit 130 applies a drive signal only to the detection drive line 115a to scan only the detection drive line 115a, thereby enabling readout of only the electrical signals from the detection pixels 112 and the correction pixels 113. Next, the imaging device control unit 160 controls the readout circuit 140 to read out the electrical signals from the columns corresponding to the detection pixels 112 and the correction pixels 113, and output them as information indicating the radiation R exposure dose. Through this operation, the radiation imaging device 100 can acquire information indicating the radiation R exposure dose obtained by the detection pixels 112 during radiation R irradiation. After this AEC driving, the drive circuit 130 sequentially supplies drive signals to the drive lines 115 to generate a diagnostic radiation image.

[0050] Fig. 3 is a diagram showing an example of a timing chart 300 in the control method of the radiation imaging apparatus 100 according to the first embodiment. Specifically, Fig. 3 is a timing chart 300 showing the operation of the radiation imaging apparatus 100 in the case of radiation imaging in which automatic exposure control (AEC) is performed based on the irradiation dose of radiation R detected by the detection pixels 112. In Fig. 3, components similar to those shown in Fig. 2 are assigned the same reference numerals, and detailed description thereof will be omitted.

[0051] In the timing chart 300 shown in Fig. 3, the horizontal direction indicates elapsed time, and the vertical direction indicates each component. The components shown in the vertical direction in Fig. 3 are, from top to bottom, drive line Vg1, detection drive line Vg2 / Vd1, drive line Vg3, drive line Vg4, detection drive line Vg5 / Vd2, drive line Vg6, ..., drive line Vgn. Next, the components shown in the vertical direction in Fig. 3 are the bias voltage Vs (before improvement) and bias voltage Vs (after improvement) of the bias line 114, and the output signal Sig (before improvement) and output signal Sig (after improvement) of the signal line 116 connected to a certain amplifier unit 141.

[0052] In FIG. 3, drive signals are sequentially supplied to the drive lines Vg1 to Vgn. Here, before generating a diagnostic radiographic image, image signals are read by applying a drive signal to the detection drive line Vd. Therefore, the output signal Sig (before improvement) at this time is small, and the effect on the bias voltage Vs (before improvement) at this time is also small. Because the bias line 114 supplies the bias voltage Vs to the pixels, it is located close to all of the signal lines 116, and fluctuations in the bias voltage Vs affect the output signal Sig. For this reason, the output signal Sig when the drive line Vg next to the detection drive line Vd is driven may have a phase delay or a maximum value change compared to the output signal Sig when the drive lines Vg are successively driven. This results in different image signal characteristics from other rows, potentially resulting in horizontal stripe artifacts. That is, as shown in the output signal Sig (before improvement), the step in the output signal Sig becomes large, which may cause artifacts in the radiographic image. Here, an example has been described in which an image signal is read by applying a drive signal to the detection drive line Vd. However, the fluctuation in the bias voltage Vs, which causes artifacts, depends on the amount of charge accumulated in the detection pixels 112 connected to the scanning detection drive line Vd. Even when no drive signal is applied to the detection drive line Vd and no image signal is read, i.e., when automatic exposure control (AEC) is not performed, the above-described artifacts can occur. Specifically, even in this case, since the pixels connected to the detection drive line Vd include the correction pixel 113, an amount of charge accumulated therein differs from the amount of charge accumulated in the imaging pixel 111 connected to the drive line Vg near the detection drive line Vd, resulting in artifacts. In light of this, in this embodiment, the internal configuration of the bias supply circuit 120 shown in FIG. 2 is configured as shown in FIGS. 4 and 5.

[0053] Fig. 4 is a diagram showing a first example of the internal configuration of the bias supply circuit 120 shown in Fig. 2 in the radiation imaging device 100 according to the first embodiment. In Fig. 4, the same components as those shown in Fig. 2 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0054] As shown in FIG. 4, the bias supply circuit 120 includes a bias power supply 121, an operational amplifier 122, a changeover switch 123, and a resistor .

[0055] The bias power supply 121 is a power supply for supplying a bias voltage Vs to the bias line 114 .

[0056] The operational amplifier 122 amplifies the difference between the input voltage from the bias power supply 121 and the bias voltage Vs (which fluctuates as shown in FIG. 3) supplied to the bias line 114, and outputs the amplified difference to the signal processing unit 150 for use in radiography that performs the above-mentioned automatic detection control. In addition, in the bias supply circuit 120 shown in FIG. 4, the output of the operational amplifier 122 is fed back to the inverting input side.

[0057] In the present embodiment, the imaging device control unit 160 determines whether or not the radiography is to be performed with automatic exposure control (AEC) based on the above-described commands and parameters input from the control device 310 via the communication unit 170 and the communication control device 220. The imaging device control unit 160 that makes this determination constitutes a determination means. If the imaging device control unit 160 determines that the radiography is to be performed with automatic exposure control (AEC), it transmits a switching control signal (e.g., a high-level signal) to the selector switch 123 to switch to the side connecting to the resistor 124. On the other hand, if the imaging device control unit 160 determines that the radiography is not to be performed with AEC, it transmits a switching control signal (e.g., a low-level signal) to the selector switch 123 to switch to the side not connecting to the resistor 124. Specifically, in the present embodiment, radiography without AEC is, for example, radiography with the above-described automatic detection control. That is, in this embodiment, the imaging device control unit 160 can also adopt a form in which it determines whether or not the radiation imaging is one that performs automatic detection control (whether or not the radiation imaging is one that performs automatic exposure control (AEC)) based on the above-mentioned commands and parameters input from the control device 310.

[0058] The changeover switch 123 switches whether to connect to the resistor 124 in response to a changeover control signal from the imaging device control unit 160. When the changeover switch 123 receives a changeover control signal from the imaging device control unit 160 to change to the side connecting to the resistor 124, the changeover switch 123 switches to the side of the first resistance value 401 where the resistor 124 is present. That is, when radiography is being performed with automatic exposure control (AEC), the changeover switch 123 switches to the side of the first resistance value 401 where the resistor 124 is present. On the other hand, when the changeover switch 123 receives a changeover control signal from the imaging device control unit 160 to change to the side not connecting to the resistor 124, the changeover switch 123 switches to the side of the second resistance value 402 where the resistor 124 is not present. That is, when radiography is being performed without AEC (in this embodiment, radiography is being performed with the above-mentioned automatic detection control), the changeover switch 123 switches to the side of the second resistance value 402 where the resistor 124 is not present. Here, the first resistance value 401 is the resistance value between the bias power supply 121 and the bias line 114, and is, for example, a resistance value in the range of 0.25Ω to 0.75Ω. The second resistance value 402 is the resistance value between the bias power supply 121 and the bias line 114, and is, for example, a resistance value in the range of 0.0Ω to 0.1Ω. That is, the first resistance value 401 is greater than the second resistance value 402. Here, in terms of the output impedance of the bias supply circuit 120, the following applies. First, the output impedance of the bias supply circuit 120 in the case of radiography with automatic exposure control (when the selector switch 123 is switched to the first resistance value 401) is defined as a first output impedance. Furthermore, the output impedance of the bias supply circuit 120 in the case of radiography with automatic detection control (when the selector switch 123 is switched to the second resistance value 402) is defined as a second output impedance. In this case, the first output impedance is greater than the second output impedance.

[0059] As described above, when the imaging device control unit 160 determines that the imaging mode is radiography with automatic exposure control (AEC), it transmits a switching control signal to the selector switch 123 to switch to the side connected to the resistor 124. Then, when the selector switch 123 receives the switching control signal from the imaging device control unit 160 to switch to the side connected to the resistor 124, it switches to the side of the first resistance value 401 where the resistor 124 is present. In this embodiment, in the case of radiography with AEC, the internal resistance value of the bias supply circuit 120 is set to the first resistance value 401, which is greater than the second resistance value 402, thereby reducing the influence on the bias voltage Vs when an image signal is read from each pixel. As a result, as shown in the bias voltage Vs (improved) in FIG. 3, the amplitude of fluctuation in the bias voltage Vs is smaller than before the improvement. Accordingly, as shown in the output signal Sig (improved) in FIG. 3, the influence on the output signal Sig is also smaller than before the improvement. That is, as shown in the output signal Sig (after improvement) in FIG. 3 , the step of the output signal Sig is smaller than before the improvement, so that artifacts that may occur in a radiographic image when radiography is performed with automatic exposure control (AEC) can be suppressed. From the perspective of the output impedance of the bias supply circuit 120, the output impedance of the bias supply circuit 120 differs depending on whether or not radiography is performed with automatic exposure control (AEC). Specifically, in this embodiment, when radiography is performed with automatic exposure control (AEC), the output impedance of the bias supply circuit 120 is larger than when radiography is performed without AEC (in this embodiment, when radiography is performed with automatic detection control). From the perspective of the output impedance of the bias supply circuit 120 as well, artifacts that may occur in a radiographic image when radiography is performed with automatic exposure control (AEC) can be suppressed, and appropriate radiography can be performed.

[0060] On the other hand, in the case of radiography with the above-described automatic detection control, which is different from radiography with automatic exposure control (AEC), increasing the internal resistance of the bias supply circuit 120 reduces the current flow and reduces the sensitivity for detecting irradiation with radiation R. This reduction in detection sensitivity for irradiation with radiation R can cause erroneous detection of irradiation with radiation R. Therefore, in this embodiment, in the case of radiography without AEC (radiography with automatic detection control), the internal resistance of the bias supply circuit 120 is set to a second resistance 402 that is smaller than the first resistance 401. This makes it possible to increase the detection sensitivity for irradiation with radiation R in the case of radiography with automatic detection control. In terms of the output impedance of the bias supply circuit 120, the output impedance of the bias supply circuit 120 differs depending on whether or not radiography is being performed with automatic detection control. Specifically, in this embodiment, in the case of radiography with automatic detection control, the output impedance of the bias supply circuit 120 is smaller than in the case of radiography without automatic detection control (in this embodiment, radiography with automatic exposure control (AEC)). From the viewpoint of the output impedance of the bias supply circuit 120, a decrease in the detection sensitivity of radiation irradiation can be suppressed in the case of radiography with automatic detection control, enabling appropriate radiography. It should be noted that, even in the case of radiography with automatic detection control, it is preferable to increase the internal resistance value of the bias supply circuit 120 (increase the output impedance of the bias supply circuit 120) when generating a radiographic image in order to suppress artifacts that may occur in the radiographic image. Therefore, in the case of radiography with automatic detection control, the internal resistance value of the bias supply circuit 120 is reduced to increase the detection sensitivity for irradiation with radiation R, but the resistance value may be increased during readout of the image signal. From the viewpoint of the output impedance of the bias supply circuit 120, the output impedance of the bias supply circuit 120 may be reduced in the case of radiography with automatic detection control, but the output impedance may be increased during readout of the image signal.In this case, for example, even in the case of radiography using automatic detection control, when image signals are being read from the pixel array, the imaging device control unit 160 sends a switching control signal to the changeover switch 123 to switch to the side connected to the resistor 124.

[0061] In addition, taking into consideration the influence of the resistance value of the switch itself, it is preferable to use a low on-resistance FET for the changeover switch 123. Furthermore, the resistor 124 may be realized by a variable resistor.

[0062] In the radiation imaging device 100 described above, the radiation detector 110 has a pixel array including a plurality of pixels 111 to 113 that acquire electrical signals corresponding to incident radiation R, including a detection pixel 112 that detects the dose of radiation R as an electrical signal. The bias line 114 is interposed between a bias power supply 121 and the plurality of pixels 111 to 113, and is configured as wiring that supplies a bias voltage Vs from the bias power supply 121 to the plurality of pixels 111 to 113. The imaging device control unit 160 controls a changeover switch 123 to place a resistor 124 between the bias power supply 121 and the bias line 114 in the case of radiography that performs automatic exposure control (AEC) based on the dose of radiation R detected by the detection pixel 112. According to this configuration, in the case of radiography using automatic exposure control (AEC), it is possible to suppress artifacts that may occur in a radiographic image based on electrical signals read out from each pixel, thereby enabling appropriate radiography.

[0063] In addition, in the case of radiography without automatic exposure control (AEC) (i.e., in the case of radiography with automatic detection control), the imaging device control unit 160 controls the changeover switch 123 so that the resistor 124 is not provided between the bias power supply 121 and the bias line 114. According to this configuration, for example, in the case of radiography using automatic detection control, it is possible to suppress a decrease in detection sensitivity when irradiating radiation R (it is possible to maintain detection sensitivity at a high level), making it possible to perform appropriate radiography.

[0064] While FIG. 4 illustrates an example in which different resistance values ​​are switched by the selector switch 123, other configurations, such as switching between different bias voltage output values, are also applicable to the present invention. FIG. 5 is a diagram showing a second example of the internal configuration of the bias supply circuit shown in FIG. 2 in the radiation imaging apparatus according to the first embodiment. In FIG. 5, components similar to those shown in FIGS. 2 and 4 are denoted by the same reference numerals, and detailed descriptions thereof will be omitted. As shown in FIG. 5, the bias supply circuit 120 includes a bias power supply 121, a selector switch 123, a first bias voltage output circuit 125, and a second bias voltage output circuit 126. The first bias voltage output value output from the first bias voltage output circuit 125 and the second bias voltage output value output from the second bias voltage output circuit 126 are different bias voltage output values. That is, the output impedance of the bias supply circuit 120 differs between when the selector switch 123 is switched to the first bias voltage output circuit 125 and when the selector switch 123 is switched to the second bias voltage output circuit 126. To obtain a different output impedance in the bias supply circuit 120, various methods may be used, such as adding a capacitor, adjusting the capacitance of the capacitor, using an operational amplifier with different characteristics, or adding an operational amplifier. From the perspective of the output impedance of the bias supply circuit 120, when the selector switch 123 in FIG. 5 is switched to the side of the first bias voltage output circuit 125, this corresponds to, for example, when the selector switch 123 in FIG. 4 is switched to the side of the first resistance value 401. Similarly, from the perspective of the output impedance of the bias supply circuit 120, when the selector switch 123 in FIG. 5 is switched to the side of the second bias voltage output circuit 126, this corresponds to, for example, when the selector switch 123 in FIG. 4 is switched to the side of the second resistance value 402. Here, the output impedance of the bias supply circuit 120 in the case of radiography with automatic exposure control (when the selector switch 123 is switched to the side of the first bias voltage output circuit 125) is defined as a first output impedance.Furthermore, the output impedance of the bias supply circuit 120 in the case of radiography with automatic detection control (when the selector switch 123 is switched to the side of the second bias voltage output circuit 126) is defined as the second output impedance. In this case, the first output impedance is greater than the second output impedance. From the viewpoint of the output impedance of the bias supply circuit 120, artifacts that may occur in radiographic images in the case of radiography with automatic exposure control (AEC) can be suppressed, enabling appropriate radiography. From the viewpoint of the output impedance of the bias supply circuit 120, from the viewpoint of the output impedance of the bias supply circuit 120, a decrease in the detection sensitivity of radiation irradiation can be suppressed in the case of radiography with automatic detection control, enabling appropriate radiography.

[0065] (Second embodiment) Next, a second embodiment will be described. In the following description of the second embodiment, matters common to the first embodiment will be omitted, and only matters different from the first embodiment will be described.

[0066] The schematic configuration of the radiation imaging system according to the second embodiment is similar to the schematic configuration of the radiation imaging system 10 according to the first embodiment shown in Fig. 1. The schematic configuration of the radiation imaging apparatus 100 according to the second embodiment is similar to the schematic configuration of the radiation imaging apparatus 100 according to the first embodiment shown in Fig. 2.

[0067] In the first embodiment described above, a configuration in which the internal resistance value of the bias supply circuit 120 is switched based on the set imaging mode is described. In the second embodiment, a configuration in which the internal resistance value of the bias supply circuit 120 is switched based on whether or not synchronous communication exists between the radiation imaging apparatus 100 and the radiation generation apparatus 230 is described. In this embodiment, in the case of radiation imaging with automatic exposure control (AEC), it is assumed that synchronous communication exists between the radiation imaging apparatus 100 and the radiation generation apparatus 230. On the other hand, in this embodiment, in the case of radiation imaging without AEC and with automatic detection control, it is assumed that synchronous communication does not exist between the radiation imaging apparatus 100 and the radiation generation apparatus 230.

[0068] Fig. 6 is a diagram showing an example of a flowchart of a control method for the radiation imaging system 10 according to the second embodiment. Specifically, Fig. 6 shows an example of processing within each of the radiation imaging apparatus 100, the radiation generation apparatus 230, and the control apparatus 310 shown in Fig. 1, and communication processing between the radiation imaging apparatus 100, the radiation generation apparatus 230, and the control apparatus 310, in the case of radiation imaging with AEC.

[0069] First, in step S501 of FIG. 6, the communication unit 170 of the radiation imaging apparatus 100 receives a command requesting preparation for imaging from the control device 310.

[0070] Subsequently, in step S502, the imaging device control unit 160 of the radiation imaging device 100 performs various imaging preparations. At this time, the various imaging preparations include a process of acquiring correction data for correction to remove offset noise components during radiation imaging using automatic exposure control (AEC), and a process of resetting each pixel by sequentially sending drive signals to the drive lines 115.

[0071] Subsequently, in step S503, the communication unit 170 of the radiation imaging apparatus 100 transmits a notification signal related to automatic exposure control (AEC) to the radiation generation apparatus 230 to check whether synchronous communication is possible.

[0072] Subsequently, in step S504, the radiation generating apparatus 230 determines whether or not a notification signal related to AEC has been received from the radiation imaging apparatus 100. If the result of this determination is that a notification signal related to AEC has not been received from the radiation imaging apparatus 100 (S504 / NO), the radiation generating apparatus 230 waits in step S504 until a notification signal related to AEC from the radiation imaging apparatus 100 can be received.

[0073] On the other hand, if the result of the determination in step S504 is that a notification signal related to AEC has been received from the radiation imaging apparatus 100 (S504 / YES), the process proceeds to step S505. In step S505, the radiation generation apparatus 230 transmits to the radiation imaging apparatus 100 a notification signal indicating that the notification signal related to AEC has been received.

[0074] Subsequently, in step S506, the radiation imaging apparatus 100 determines whether or not a notification signal indicating that a notification signal related to AEC has been received from the radiation generation apparatus 230. If the result of this determination is that a notification signal indicating that a notification signal related to AEC has been received from the radiation generation apparatus 230 (S506 / NO), the process returns to step S503 and repeats the processes from step S503 onward.

[0075] On the other hand, if it is determined in step S506 that a notification signal indicating that the notification signal related to AEC has been received from the radiation generation device 230 (S506 / YES), the process proceeds to step S507. In step S507, the imaging device control unit 160 of the radiation imaging device 100 transmits a switching control signal to the changeover switch 123 to switch to the side connected to the resistor 124 in Fig. 4 in preparation for radiation imaging with automatic exposure control (AEC). When the changeover switch 123 receives the switching control signal to switch to the side connected to the resistor 124 from the imaging device control unit 160, the changeover switch 123 switches to the side of the first resistance value 401 where the resistor 124 in Fig. 4 is present.

[0076] Subsequently, in step S508, the communication unit 170 of the radiation imaging apparatus 100 outputs (transmits) an irradiation permission signal for radiation R to the radiation generation apparatus 230.

[0077] Then, upon receiving the radiation R irradiation permission signal from the radiation imaging apparatus 100, the radiation generation apparatus 230 subsequently starts irradiating the subject H and the radiation imaging apparatus 100 with radiation R from the radiation source 240 in step S509.

[0078] After the radiation imaging apparatus 100 transmits the radiation R irradiation permission signal to the radiation generation apparatus 230, the imaging apparatus control unit 160 subsequently starts the AEC operation in step S510.

[0079] Next, in step S511, the imaging device control unit 160 of the radiation imaging device 100 determines whether the exposure dose of radiation R detected by the detection pixels 112 of the radiation detector 110 has reached the threshold value. If the result of this determination is that the exposure dose of radiation R detected by the detection pixels 112 of the radiation detector 110 has not reached the threshold value (S511 / NO), the process returns to step S510 and repeats the processes from step S510 onwards.

[0080] On the other hand, if the result of the determination in step S511 is that the irradiation dose of the radiation R detected by the detection pixels 112 of the radiation detector 110 has reached the threshold value (S511 / YES), the process proceeds to step S512. In step S512, the communication unit 170 of the radiation imaging apparatus 100 outputs (transmits) a radiation R irradiation stop signal to the radiation generation apparatus 230.

[0081] Subsequently, upon receiving the radiation R irradiation stop signal from the radiation imaging apparatus 100, the radiation generation apparatus 230 subsequently stops the irradiation of radiation R from the radiation source 240 in step S513.

[0082] Furthermore, after the radiation imaging device 100 transmits a radiation R irradiation stop signal to the radiation generation device 230, the imaging device control unit 160 subsequently performs an imaging operation of the subject H using the imaging pixels 111 of the radiation detector 110 in step S514.

[0083] Subsequently, in step S515, the communication unit 170 of the radiation imaging apparatus 100 transmits to the control device 310 the radiation image of the subject H obtained in the imaging operation in step S514.

[0084] Subsequently, in step S516, the control device 310 determines whether or not a radiological image of the subject H obtained in the imaging operation of step S514 has been received from the radiation imaging device 100. If the result of this determination is that a radiological image of the subject H obtained in the imaging operation of step S514 has not been received from the radiation imaging device 100 (S516 / NO), the control device 310 waits in step S516 until a radiological image of the subject H is received.

[0085] On the other hand, if the result of the determination in step S516 is that the radiographic image of the subject H obtained in the imaging operation in step S514 has been received from the radiation imaging apparatus 100 (S516 / YES), the process proceeds to step S517. In step S517, the control device 310 transmits a notification signal to the radiation imaging device 100 indicating that the radiation image of the subject H has been received. Then, when the process of step S517 ends, the process of the flowchart shown in FIG. 6 ends.

[0086] In the second embodiment, the imaging apparatus control unit 160 determines that radiation imaging is performed with automatic exposure control (AEC) when synchronous communication is established between the radiation imaging apparatus 100 and the radiation generation apparatus 230. Furthermore, when synchronous communication is not established between the radiation imaging apparatus 100 and the radiation generation apparatus 230, the imaging apparatus control unit 160 determines that radiation imaging is not performed with AEC. For example, the imaging apparatus control unit 160 may determine whether radiation imaging is performed with automatic exposure control (AEC) by detecting insertion or removal of a synchronous communication cable for performing synchronous communication as the communication cable 201 for the wired communication unit 103 of the radiation imaging apparatus 100. Note that, in this embodiment, synchronous communication is communication of at least one signal selected from an irradiation permission signal, an irradiation start signal, and an irradiation stop signal for radiation R. Note that, in the present invention, synchronous communication is not limited to these signals, and synchronous communication may be confirmed by, for example, checking a response to a Ping command.

[0087] In the second embodiment, the imaging device control unit 160 determines that radiation imaging is to be performed with automatic exposure control (AEC) when synchronous communication is established between the radiation imaging device 100 and the radiation generation device 230. When synchronous communication is established between the radiation imaging device 100 and the radiation generation device 230, the imaging device control unit 160 controls the changeover switch 123 to switch the switch to the first resistance value 401 side where the resistor 124 in FIG. 4 is present. On the other hand, when synchronous communication is not established between the radiation imaging device 100 and the radiation generation device 230, the imaging device control unit 160 determines that radiation imaging is not to be performed with AEC, for example, radiation imaging is to be performed with automatic detection control. When synchronous communication is not established between the radiation imaging device 100 and the radiation generation device 230, the imaging device control unit 160 controls the changeover switch 123 to switch the switch to the second resistance value 402 side where the resistor 124 in FIG. 4 is not present.

[0088] As described above, in the second embodiment, whether or not to provide the resistor 124 between the bias power supply 121 and the bias line 114 is determined based on whether or not synchronous communication exists between the radiation imaging apparatus 100 and the radiation generation apparatus 230. According to this configuration, similar to the first embodiment described above, when performing radiography with automatic exposure control (AEC), artifacts that may occur in a radiographic image based on electrical signals read from each pixel can be suppressed, enabling appropriate radiography. Furthermore, when performing radiography with automatic detection control, for example, it is possible to suppress a decrease in detection sensitivity in the irradiation of radiation R (maintaining detection sensitivity at a high level), enabling appropriate radiography. While the example using FIG. 4 has been described in the second embodiment, a configuration using FIG. 5 is also applicable. In this configuration, switching the selector switch 123 to the first resistance value 401, where the resistor 124 in FIG. 4 is present, corresponds to switching the selector switch 123 to the first bias voltage output circuit 125 in FIG. 5. Switching the selector switch 123 to the second resistance value 402, where the resistor 124 in FIG. 4 is not present, corresponds to switching the selector switch 123 to the second bias voltage output circuit 126 in FIG. 5.

[0089] In this embodiment, the processing performed by the radiation imaging apparatus 100 after receiving the imaging preparation request in step S501 and the processing performed after receiving the AEC communication reception notification in step S505 are not limited to the processing in the flowchart shown in Fig. 6 and can be modified as appropriate. Furthermore, when the radiation imaging system 10 is configured such that a relay unit is connected between the radiation imaging apparatus 100 and the radiation generation apparatus 230, it may be determined whether or not the above-mentioned synchronous communication is present by checking synchronous communication between the radiation imaging apparatus 100 and the relay unit. In this case, since the relay unit may not be compatible with radiation imaging that performs automatic exposure control (AEC), it is preferable to simultaneously check whether or not the relay unit is compatible with radiation imaging that performs AEC.

[0090] (Other embodiments) The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions. This program and a computer-readable storage medium storing the program are included in the present invention.

[0091] It should be noted that the above-described embodiments of the present invention are merely illustrative examples of the implementation of the present invention, and the technical scope of the present invention should not be construed as being limited by these. In other words, the present invention can be implemented in various forms without departing from its technical concept or main features.

[0092] The disclosure of this embodiment includes the following configuration, method, and program. [Configuration 1] a pixel array including a plurality of pixels that acquire electrical signals corresponding to incident radiation, the plurality of pixels including detection pixels that detect the dose of the radiation as the electrical signals; a bias supply circuit for supplying a bias voltage to the plurality of pixels; and The output impedance of the bias supply circuit differs depending on whether or not the case is radiography in which automatic exposure control is performed based on the dose of the radiation detected by the detection pixel. A radiation imaging apparatus characterized by: [Configuration 2] a pixel array including a plurality of pixels that acquire electrical signals corresponding to incident radiation, the plurality of pixels including detection pixels that detect the dose of the radiation as the electrical signals; a bias supply circuit for supplying a bias voltage to the plurality of pixels; and The output impedance of the bias supply circuit differs depending on whether or not the radiography is performed with automatic detection control for automatically detecting the irradiation of the radiation onto the pixel array. A radiation imaging apparatus characterized by: [Configuration 3] In the case of radiography in which the automatic detection control is performed, the output impedance of the bias supply circuit differs depending on whether the electrical signal is being read out from the pixel. 3. The radiation imaging apparatus according to configuration 2. [Configuration 4] In the case of radiography in which the automatic detection control is performed, a switching unit is further provided for switching the output impedance of the bias supply circuit depending on whether the electrical signal is being read out from the pixel. 4. The radiation imaging device according to configuration 2 or 3. [Configuration 5] the output impedance of the bias supply circuit in the case of radiography with the automatic exposure control is set to a first output impedance; When the output impedance of the bias supply circuit in the case of radiography in which automatic detection control is performed to automatically detect the irradiation of the radiation to the pixel array is set to a second output impedance, The first output impedance is greater than the second output impedance. 2. The radiation imaging device according to configuration 1, [Configuration 6] The present invention further includes a switching unit that switches the output impedance of the bias supply circuit depending on whether the radiography is performed with the automatic exposure control or with automatic detection control that automatically detects the irradiation of the radiation on the pixel array. 2. The radiation imaging device according to configuration 1, [Configuration 7] The radiography device further includes a determination unit for determining whether the radiography is performed with the automatic exposure control or the automatic detection control, The switching means switches the output impedance of the bias supply circuit based on the result of the determination by the determining means. 7. The radiation imaging device according to configuration 6, [Configuration 8] The determination means determines whether the radiography is to be performed with the automatic exposure control or the automatic detection control based on a command or parameter input from a control device communicably connected to the radiography apparatus. 8. The radiation imaging device according to configuration 7, [Configuration 9] The command is a command indicating ON / OFF of the automatic exposure control function or a command indicating an imaging mode related to radiation imaging. 9. The radiation imaging device according to configuration 8. [Configuration 10] The command indicating that the automatic exposure control function is turned off is a command indicating that the automatic detection control function is turned on. 10. The radiation imaging device according to configuration 9, [Configuration 11] The parameters are: The automatic exposure control function includes at least one of a selected region in the region of interest of the pixel array, a threshold value for the radiation dose, a calculation method when using a plurality of the regions of interest, a sensitivity correction value, a density correction value, and a sensor rotation angle. 11. The radiation imaging device according to any one of configurations 8 to 10. [Configuration 12] The parameters include at least one of a detection sensitivity and a detection threshold of the automatic detection control function. 11. The radiation imaging device according to any one of configurations 8 to 10. [Configuration 13] The determination means If there is synchronous communication between the radiation imaging device and a radiation generating device that generates the radiation, it is determined that the radiation imaging is performed with the automatic exposure control, If there is no synchronous communication between the radiation imaging device and the radiation generating device, it is determined that the radiation imaging is to be performed with the automatic detection control. 11. The radiation imaging device according to any one of configurations 7 to 10. [Configuration 14] The synchronous communication is communication of at least one signal selected from the group consisting of an irradiation permission signal, an irradiation start signal, and an irradiation stop signal. 14. The radiation imaging apparatus according to claim 13, [Configuration 15] The determining means determines whether the radiography is performed with the automatic exposure control or the automatic detection control by detecting the insertion or removal of a synchronous communication cable for performing the synchronous communication with respect to the radiographic imaging device. 15. The radiation imaging device according to configuration 13 or 14. [Method 1] a pixel array including a plurality of pixels that acquire electrical signals corresponding to incident radiation, the plurality of pixels including detection pixels that detect the dose of the radiation as the electrical signals; a bias supply circuit for supplying a bias voltage to the plurality of pixels; A method for controlling a radiation imaging apparatus comprising: a control step of performing different control over the output impedance of the bias supply circuit depending on whether or not the case is radiography in which automatic exposure control based on the dose of the radiation detected by the detection pixel is performed. A method for controlling a radiation imaging apparatus, comprising: [Method 2] a pixel array including a plurality of pixels that acquire electrical signals corresponding to incident radiation, the plurality of pixels including detection pixels that detect the dose of the radiation as the electrical signals; a bias supply circuit for supplying a bias voltage to the plurality of pixels; A method for controlling a radiation imaging apparatus comprising: a control step of performing control such that the output impedance of the bias supply circuit is different depending on whether or not the case is radiography in which automatic detection control is performed to automatically detect the irradiation of the radiation to the pixel array. A method for controlling a radiation imaging apparatus, comprising: [Program 1] A program for causing a computer to execute the steps of the method for controlling a radiation imaging apparatus according to the first or second method. [Explanation of symbols]

[0093] 10: Radiation imaging system, 11: Radiation room, 12: Control room, 100: Radiation imaging device, 101: Power supply control unit, 102: Wireless communication unit, 103: Wired communication unit, 110: Radiation detector, 111: Imaging pixel, 112: Detection pixel, 113: Correction pixel, 114: Bias line, 115: Drive line, 116: Signal line, 120: Bias supply circuit, 121: Bias power supply, 122: Operational amplifier, 123: Changeover switch, 124: Resistor, 125: First bias voltage output circuit, 126: Second bias voltage output circuit, 130: Drive circuit, 140: Readout circuit, 141: Amplification unit, 142: Multiplexer, 143: Analog Digital converter, 150: signal processing unit, 151: calculation unit, 152: memory unit, 160: imaging device control unit, 170: communication unit, 201: radiation imaging device communication cable, 202: AP communication cable, 203: radiation generator communication cable, 204: radiation source communication cable, 210: access point (AP), 220: communication control device, 230: radiation generator, 240: radiation source, 310: control device, 320: radiation irradiation switch, 330: input device, 340: display device, 350: hospital LAN, 360: radiation room communication cable, 401: first resistance value, 402: second resistance value, H: subject, R: radiation, S: operator

Claims

1. a pixel array including a plurality of pixels that acquire electrical signals corresponding to incident radiation, the plurality of pixels including detection pixels that detect the dose of the radiation as the electrical signals; a bias supply circuit for supplying a bias voltage to the plurality of pixels; and The output impedance of the bias supply circuit differs depending on whether or not the case is radiography in which automatic exposure control is performed based on the dose of the radiation detected by the detection pixel. A radiation imaging apparatus characterized by:

2. a pixel array including a plurality of pixels that acquire electrical signals corresponding to incident radiation, the plurality of pixels including detection pixels that detect the dose of the radiation as the electrical signals; a bias supply circuit for supplying a bias voltage to the plurality of pixels; and The output impedance of the bias supply circuit differs depending on whether or not the radiography is performed with automatic detection control for automatically detecting the irradiation of the radiation onto the pixel array. A radiation imaging apparatus characterized by:

3. In the case of radiography in which the automatic detection control is performed, the output impedance of the bias supply circuit differs depending on whether the electrical signal is being read out from the pixel.

3. The radiation imaging apparatus according to claim 2.

4. In the case of radiography in which the automatic detection control is performed, a switching unit is further provided for switching the output impedance of the bias supply circuit depending on whether the electrical signal is being read out from the pixel.

3. The radiation imaging apparatus according to claim 2.

5. the output impedance of the bias supply circuit in the case of radiography with the automatic exposure control is set to a first output impedance; When the output impedance of the bias supply circuit in the case of radiography in which automatic detection control is performed to automatically detect the irradiation of the radiation to the pixel array is set to a second output impedance, The first output impedance is greater than the second output impedance.

2. The radiation imaging apparatus according to claim 1.

6. The present invention further includes a switching unit that switches the output impedance of the bias supply circuit depending on whether the radiography is performed with the automatic exposure control or with automatic detection control that automatically detects the irradiation of the radiation on the pixel array.

2. The radiation imaging apparatus according to claim 1.

7. The radiography device further includes a determination unit for determining whether the radiography is performed with the automatic exposure control or the automatic detection control, The switching means switches the output impedance of the bias supply circuit based on the result of the determination by the determining means.

7. The radiation imaging apparatus according to claim 6.

8. The determination means determines whether the radiography is to be performed with the automatic exposure control or the automatic detection control based on a command or parameter input from a control device communicably connected to the radiography apparatus.

8. The radiation imaging apparatus according to claim 7.

9. The command is a command indicating ON / OFF of the automatic exposure control function or a command indicating an imaging mode related to radiation imaging.

9. The radiation imaging apparatus according to claim 8.

10. The command indicating that the automatic exposure control function is turned off is a command indicating that the automatic detection control function is turned on.

10. The radiation imaging apparatus according to claim 9.

11. The parameters include at least one of a selected region in the region of interest of the pixel array used in the automatic exposure control function, a threshold value related to the radiation dose, a calculation method when using a plurality of the regions of interest, a sensitivity correction value, a density correction value, and a sensor rotation angle.

9. The radiation imaging apparatus according to claim 8.

12. The parameters include at least one of a detection sensitivity and a detection threshold of the automatic detection control function.

9. The radiation imaging apparatus according to claim 8.

13. The determination means If there is synchronous communication between the radiation imaging device and a radiation generating device that generates the radiation, it is determined that the radiation imaging is performed with the automatic exposure control, If there is no synchronous communication between the radiation imaging device and the radiation generating device, it is determined that the radiation imaging is to be performed with the automatic detection control.

8. The radiation imaging apparatus according to claim 7.

14. The synchronous communication is communication of at least one signal selected from the group consisting of an irradiation permission signal, an irradiation start signal, and an irradiation stop signal.

14. The radiation imaging apparatus according to claim 13.

15. The determining means determines whether the radiography is performed with the automatic exposure control or the automatic detection control by detecting the insertion or removal of a synchronous communication cable for performing the synchronous communication with respect to the radiographic imaging device.

14. The radiation imaging apparatus according to claim 13.

16. A method for controlling a radiation imaging apparatus including: a pixel array including a plurality of pixels that acquire electrical signals corresponding to incident radiation, the plurality of pixels including detection pixels that detect a dose of the radiation as the electrical signals; and a bias supply circuit that supplies a bias voltage to the plurality of pixels, a control step of performing different control over the output impedance of the bias supply circuit depending on whether or not the case is radiography in which automatic exposure control based on the dose of the radiation detected by the detection pixel is performed. A method for controlling a radiation imaging apparatus, comprising:

17. A method for controlling a radiation imaging apparatus including: a pixel array including a plurality of pixels that acquire electrical signals corresponding to incident radiation, the plurality of pixels including detection pixels that detect a dose of the radiation as the electrical signals; and a bias supply circuit that supplies a bias voltage to the plurality of pixels, a control step of performing control such that the output impedance of the bias supply circuit is different depending on whether or not the case is radiography in which automatic detection control is performed to automatically detect the irradiation of the radiation to the pixel array. A method for controlling a radiation imaging apparatus, comprising:

18. 18. A program for causing a computer to execute the steps of the method for controlling a radiation imaging apparatus according to claim 16 or 17.

Images