JP2021078693A - Radiographic apparatus, radiographic system, control method of radiographic apparatus, and program - Google Patents

Abstract

To achieve both an increase in a frame rate of moving image photography and suppression of deterioration in image quality in image transfer.SOLUTION: A radiographic apparatus includes: a radiation detection unit having a plurality of pixels; a reading unit for reading image data based on output of the plurality of pixels and data for image correction for correcting the image data from the radiation detection unit; a communication unit for communicating with an external apparatus; and a transfer control unit for causing a dummy transfer operation of the communication unit to be executed so that power consumption of the communication unit is substantially the same in an acquisition period of the image data and an acquisition period of the data for image correction.SELECTED DRAWING: Figure 1

Description

The present invention relates to a radiographic apparatus, a radiological imaging system, a control method and a program of the radiological imaging apparatus.

As a radiographic apparatus used for medical image diagnosis using radiation such as X-rays, a radiographic apparatus having a pixel array in which a switch such as a TFT (thin film) and a conversion element such as a photoelectric conversion element are combined is known. The image data acquired by the radiography device can be used for optical fiber communication using an optical module, wired communication such as Ethernet (registered trademark), or external communication such as a control device or image processing device for the radiography device by the communication unit of wireless communication. Transferred to the device.

According to Patent Document 1, when a radiation image is read and the radiation image data is wirelessly transferred to a transfer destination, noise caused by the radio does not affect the image being read and deterioration of image quality is prevented. The control method of the radiography apparatus is described.

Further, Patent Document 2 describes a control method of a radiation photographing apparatus for suppressing moving heat in a reading circuit and a signal transmission unit during moving image shooting and for moving image shooting without artifacts.

Japanese Unexamined Patent Publication No. 2006-87566 Japanese Unexamined Patent Publication No. 2008-29816

In the method described in Patent Document 1, in moving image photography, the transfer of image data from the radiography apparatus to the external apparatus is slowed down, and the frame rate is limited. On the other hand, in the method described in Patent Document 2, the image quality deteriorates when the operation period of the readout circuit and the transfer period of the image data to the external device deviate from each other due to the data processing and the communication status in the radiography apparatus. There was a problem.

In view of the above-mentioned problems, it is an object of the present invention to achieve both high speed of the frame rate of moving image shooting and suppression of deterioration of image quality in image transfer.

The radiography apparatus according to one aspect of the present invention for achieving the above object has the following configuration. That is, a reading unit that reads out a radiation detection unit having a plurality of pixels, image data based on the output of the plurality of pixels, and image correction data for correcting the image data from the radiation detection unit, and an external unit. The dummy transfer operation of the communication unit is performed so that the power consumption of the communication unit in the communication unit communicating with the device, the acquisition period of the image data, and the acquisition period of the image correction data is substantially the same. It includes a transfer control unit to be executed.

According to the present invention, it is possible to achieve both high speed of the frame rate of moving image shooting and suppression of deterioration of image quality in image transfer.

The figure which shows an example of the schematic structure of the radiography system which concerns on 1st Embodiment. The figure which shows an example of the internal structure of the radiation detection part which concerns on 1st Embodiment. The timing chart which shows the transfer operation of the radiography apparatus which concerns on 1st Embodiment. A timing chart showing another transfer operation of the radiography apparatus according to the first embodiment. A timing chart showing another transfer operation of the radiography apparatus according to the first embodiment. The timing chart which shows another transfer operation of the radiography apparatus which concerns on 2nd Embodiment. The timing chart which shows another transfer operation of the radiography apparatus which concerns on 2nd Embodiment. The figure which shows an example of the internal structure of the radiation detection part which concerns on 3rd Embodiment.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the following embodiments, the term radiation may include, for example, α-rays, β-rays, γ-ray particle beams, cosmic rays, etc., in addition to X-rays. In addition, the following embodiments can be combined as appropriate, and embodiments in which the embodiments are appropriately combined are also included in the embodiments of the present invention.

(First Embodiment)
FIG. 1 is a diagram showing an example of a schematic configuration of a radiography system 100 according to a first embodiment of the present invention. As shown in FIG. 1, the radiography system 100 includes a radiography device 101, a radiation source 112, a radiation control device 114, an access point (AP) 117, an irradiation control device 120, and a system control device 130. There is. AP117 can be configured as an integral part of the irradiation control device 120. Further, although not shown, it is possible to connect to a RIS (Radiological Information System), a PACS (Medical Image Management System), a printer, or the like.

The radiography apparatus 101 is configured to be communicable with the irradiation control apparatus 120, which is an external device. Specifically, the radiography apparatus 101 is configured to enable wired communication with the irradiation control device 120, which is an external device. Further, the radiography apparatus 101 is configured to enable wireless communication with the irradiation control apparatus 120, which is an external device, via AP117. As shown in FIG. 1, the radiography apparatus 101 includes a radiation detection unit 200, an imaging control unit 102, a storage unit 103, a wireless communication unit 104, a wired communication unit 105, a power supply control unit 106, and a battery 107. It is composed of.

The radiation detection unit 200 detects the radiation (including the radiation transmitted through the subject 116) 115 emitted from the radiation source 112 and acquires the image data of the subject 116. At this time, the radiation detection unit 200 can acquire image data of still images and moving images as image data. Further, as the radiation detection unit 200, for example, it is preferable to use a flat panel detector.

The imaging control unit 102 performs various controls related to radiography of the radiography apparatus 101. The imaging control unit 102 includes an image reading control unit 108 that controls the drive of the radiation detection unit 200 and controls the acquisition of radiation image data from the radiation detection unit 200, and image processing that performs various image processing on the acquired image data. It is configured to have a unit 110. In addition, the photographing control unit 102 also performs storage control of image data for the storage unit 103, transfer control of image data to the irradiation control device 120 via the wireless communication unit 104 and the wired communication unit 105, and the like. The image reading control unit 108 sets the drive timing and drive conditions of the radiation detection unit 200 as the drive control of the radiation detection unit 200. The image processing unit 110 may include image processing functions including correction processing for correcting (defects, offsets, gains) acquired image data, processing for reducing various noises, gradation processing, and the like. it can. Further, some or all of the functions of the image processing unit 110 of the radiography apparatus 101 can be possessed by the irradiation control device 120 and the system control device 130, which will be described later, depending on the required system configuration. The transfer control unit 109 controls the storage and transfer of the acquired image data. The timing adjustment unit 111 adjusts the execution timing of reading and transferring the image data.

The storage unit 103 stores a program for controlling the operation of the radiography apparatus 101, various information necessary for the control, and various data. Further, the storage unit 103 stores various information and various data obtained by, for example, the processing of the photographing control unit 102. For example, the storage unit 103 stores the image data obtained by the shooting control unit 102 and the image data (corrected image data) that has undergone various processing such as correction based on the control of the shooting control unit 102. Further, the power consumption of the communication unit (wireless communication unit 104, wired communication unit 105) used at the time of acquiring the image data and the image correction data is stored.

The wireless communication unit 104 performs wireless communication with the irradiation control device 120 via the AP 117, for example, by wireless LAN. Further, the wired communication unit 105 performs wired communication with the irradiation control device 120 by wire (cable). The photographing control unit 102 uses either or both of the wireless communication unit 104 and the wired communication unit 105 to communicate with the irradiation control device 120, for example, command communication, X-ray synchronization control communication, image data communication, and the like. I do. In addition, the photographing control unit 102 grasps the state of whether the wired cable is connected, and determines whether the wired communication is connected or disconnected from the irradiation control device 120. Although wireless communication via AP117 is shown in FIG. 1, the radiographing device 101 or the irradiation control device 120 may serve as an access point for direct wireless communication, and Bluetooth (registered trademark) or the like may be used for direct wireless communication. Wireless communication may be performed via another wireless communication means. Further, in the wired communication between the radiography apparatus 101 and the irradiation control device 120, for example, wired communication by Ethernet (registered trademark) or the like can be performed.

The power supply control unit 106 controls the power supply that supplies power to each component of the radiation imaging device 101 such as the radiation detection unit 200 and the imaging control unit 102, based on the control of the imaging control unit 102. The battery 107 is a power source provided inside the radiography apparatus 101. For example, when the wired communication is not disconnected (when the wired communication is established (connected)), the power supply control unit 106 uses the power supply 122 of the irradiation control device 120, which is an external device, to use the radiation imaging device 101. Power is supplied to each component of the above, and control is performed to operate each component. Further, when the wired communication is disconnected, the power supply control unit 106 uses the battery 107 provided inside the radiography apparatus 101 to supply power to each component of the radiography apparatus 101, and each of the components is supplied with power. Controls the operation of the components. In the present embodiment, the battery 107 is provided inside the radiography apparatus 101, but may be configured as a battery that can be attached to and detached from the radiography apparatus 101, for example. Further, the battery 107 of the present embodiment can be charged by receiving a power supply from the outside, for example, a secondary battery such as a lithium ion battery or a nickel hydrogen battery, a lithium ion capacitor, an electric double layer capacitor or the like. It is also possible to use the power storage device of.

The radiation source 112 is a device that generates radiation 115 such as X-rays. The radiation source 112 is composed of, for example, an electron gun and a rotor. In this case, the radiation 115 is generated by the electrons colliding with the rotor while being accelerated by the high voltage generated by the radiation control device 114.

The system control device 130 is a device that comprehensively controls the operation of the radiography system 100. The system control device 130 performs various controls such as control of the operation of the radiography system 100, acquisition and setting of a radiography protocol, data processing of a radiological image taken by the radiography camera 101, and the like. The system control device 130 includes a control unit 131, a display unit 132, and an operation unit 133. The control unit 131 has an application function that operates on the computer. That is, the control unit 131 has one or more processors and a memory, and the processors execute a program stored in the memory to realize each functional unit described below. However, some or all of each functional unit may be realized by dedicated hardware. As the control unit 131, for example, various computers, workstations, and the like can be preferably used. The control unit 131 is connected to a display device 132 such as a display for displaying control menu information and a radiographic image after imaging, and an input device 133 such as a mouse or keyboard for performing various inputs. Has been done. The control unit 131 outputs an image to the display unit 132 and provides a graphical user interface using the display unit 132 while controlling the operation of the radiography apparatus 101. Although the control unit 131, the display unit 132, and the operation unit 133 are shown as one, they may be separated from each other.

The irradiation control device 120 functions as an interface device connected to the radiography device 101, the system control device 130, and the radiation control device 114. The irradiation control device 120 controls to synchronize the image acquisition timing of the radiography apparatus 101 with the X-ray irradiation timing of the radiation control device 114. Further, the irradiation control device 120 is connected to the system control device 130 by Ethernet (registered trademark) or the like, and also functions as a relay device when transferring the image data acquired by the radiography apparatus 101 to the system control device 130. The irradiation control device 120 includes a wired communication unit 121 that performs wired communication with the radiation imaging device 101, a power supply 122 that enables power supply to the radiation imaging device 101, and an irradiation pulse generation unit 123 that issues an irradiation request to the radiation control device 114. It is configured to have.

The radiation control device 114 controls the radiation 115 generated from the radiation source 112. The radiation control device 114 may be connected to, for example, a switch that requires radiography such as an exposure button or a fluoroscopic pedal, and an operation unit that sets radiation irradiation conditions and the like.

Next, the internal configuration of the radiation detection unit 200 shown in FIG. 1 will be described.

FIG. 2 is a diagram showing an example of the internal configuration of the radiation detection unit 200 shown in FIG. As shown in FIG. 2, the radiation detection unit 200 includes a drive circuit 201, a sensor array 202, a sample hold circuit 203, a multiplexer 204, an amplifier 205, and an A / D converter 206.

The drive circuit 201 drives a plurality of pixels 207 provided in the sensor array 202 under the control of the photographing control unit 102.

The sensor array 202 includes a plurality of pixels 207. Specifically, the sensor array 202 is arranged in a two-dimensional array in which a plurality of pixels 207 form a plurality of rows and a plurality of columns.

One pixel 207 includes a conversion element 209 that converts the incident radiation 115 into a signal charge (electric signal), and a switch element 208 such as a TFT that transfers the electric signal to the outside.

In the present embodiment, the conversion element 209 includes a scintillator (phosphor) that converts the incident radiation 115 into light such as visible light, and a photoelectric conversion element that converts the light converted by the scintillator into a signal charge. It is configured. The present invention is not limited to this embodiment, and a so-called direct conversion type conversion element that directly converts the incident radiation 115 into a signal without providing a scintillator may be used as the conversion element 209. It is possible.

By switching ON and OFF of the switch element 208 via the drive line 211 by the drive circuit 201, the charge of the conversion element 209 is accumulated and the charge is read out, and as a result, a radiation image can be acquired. Specifically, when the ON voltage of the switch element 208 is applied to the predetermined drive line 211 by the drive circuit 201, the switch element 208 of each pixel 207 in the row connected to the predetermined drive line 211 is turned ON. become. The electric charge of the conversion element 209 corresponding to the turned on switch element 208 is held in the sample hold circuit 203 via the respective signal lines 210. After that, the signal charges held in the sample hold circuit 203 are sequentially read out via the multiplexer 204, amplified by the amplifier 205, and then converted into digital radiographic image data by the A / D converter 206. Further, each pixel 207 in the row in which the charge reading is completed returns to the state of charge accumulation by applying the OFF voltage of the switch element 208 to the predetermined drive line 211 by the drive circuit 201.

In this way, the drive circuit 201 sequentially drives and scans the pixels 207 in each row of the sensor array 202, and finally the signal charges of all the pixels 207 are converted into digital values. As a result, the image data can be read out. Then, control of driving and reading operation of these radiation detection units 200 is performed by the image reading control unit 108 in the imaging control unit 102 shown in FIG.

Further, the imaging control unit 102 sets the operating state of the radiation detection unit 200 from the imaging order and imaging mode information set from the system control device 130 and the connection state of the wired cable, and controls to drive the radiation detection unit 200. Do. Further, when the imaging control unit 102 receives the imaging request signal from the irradiation control device 120, the imaging control unit 102 can perform the imaging operation of the moving image and the still image while synchronizing with the irradiation control device 120. Then, after the image processing unit 110 performs necessary image processing on the image data acquired by the photographing operation, the photographing control unit 102 transfers the storage control to the storage unit 103 and the transfer control to the external device. This is done by the control unit 109. Specifically, the image data is transferred from the radiography apparatus 101 to the system control apparatus 130 via the irradiation control apparatus 120.

Each pixel 207 of the sensor array 202 has different characteristics. The main characteristic variation is the variation of offset (dark current) and gain (conversion efficiency). The outline of the offset correction and the gain correction performed by the image processing unit 110 will be described below.

The image processing unit 110 performs offset correction on the image data in order to remove the dark current component of the conversion element 209 that is generated regardless of the irradiation of radiation. The dark current component used in the offset correction is, for example, immediately after the acquisition of the image data including the image information of the subject 116, the charge is charged without irradiating the charge for the same time as the charge accumulation time when the image information of the subject 116 is acquired. Can be obtained by accumulating. The image data acquired at this time is hereinafter referred to as offset data. Offset correction is performed by subtracting offset data from the image data (raw data) before correction.

Next, the image processing unit 110 performs gain correction on the image data after offset correction in order to correct variations in conversion efficiency between pixels. The image data used in the gain correction can be acquired by irradiating the subject 116 without arranging the subject 116. The image data acquired at this time is hereinafter referred to as gain data. The offset data and the gain data are used as image correction data, but can be used for display and various processing as images and maps, respectively.

The gain correction is performed by dividing the image data after the offset correction by the gain data and then multiplying by an appropriate coefficient such as the average value of the entire gain data.

Since the acquisition of gain data involves irradiation, it is difficult to acquire the data at the time of acquiring the radiation image of the subject 116. Therefore, the gain data is acquired, for example, once a day or once a week.

FIG. 3 is a timing chart showing an operation of reading image data of the radiography apparatus 101 according to the first embodiment of the present invention and an operation of transferring image data to an external device. Immediately after acquiring the image data irradiated with the radiation 115, the radiation photographing apparatus 101 repeatedly operates to acquire the offset data not irradiated with the radiation 115.

In FIG. 3, the radiation irradiation shows the irradiation of the radiation generated from the radiation source 112 to the subject 116. The read operation indicates the read timing of the radiation detection unit 200. The transfer operation indicates the transfer timing of data including image data from the radiography apparatus 101 to the irradiation control apparatus 120 and the system control apparatus 130.

The shooting sequence will be described with reference to FIG. The radiography apparatus 101 alternately acquires image data and offset data. During the image data acquisition period, first, all the switch elements 208 of the sensor array 202 are turned off, the conversion element 209 is shifted to the storage drive, and the radiation detection unit 200 is irradiated with the radiation 115. Charges are accumulated in the conversion element 209 in response to the irradiation of the radiation 115. Next, the operation shifts to the read drive, and the switch element 208 is sequentially turned on by the operation of the image read control unit 108 to read the image data from the conversion element 209. Next, during the offset data acquisition (time of the same length as the storage period of the image data in the absence of irradiation), all the switch elements 208 of the sensor array 202 are turned off and the conversion element 209 is shifted to the storage drive. , Charge is accumulated in the conversion element 209. Next, the operation shifts to the read-out drive, and the switch element 208 is sequentially turned on by the operation of the image read-out control unit 108 to read the offset data from the conversion element 209. Then, the irradiation and the reading operation are repeated for the next shooting. During the offset data acquisition, in parallel with the offset data reading, the image processing unit 110 subtracts the pixel value of the offset data read from the pixel value of the image data for each pixel, and the image after offset correction. Generate data. The image data after the offset correction is transferred from the radiography apparatus 101 to the external device by the transfer control unit 109.

In the transfer operation, the transfer operation period is due to various factors such as the speed limit of the communication module of the wireless communication unit 104 and the wired communication unit 105, the deterioration of the communication quality, and the increase of the image processing time in the radiography apparatus 101. May be longer. At this time, due to the difference between the reading operation period and the image data transfer period to the external device, a period during which the transfer operation is stopped occurs during the reading period. A stepped artifact for each region is generated in one frame so as to correspond to the fluctuation of the power consumption due to the change of the transfer operation during the reading period. This is because fluctuations in the power supply to the communication module affect the operation of other devices (eg, sample hold circuit 203, multiplexer 204, amplifier 205, A / D converter 206) that receive power from a common power supply. It is thought that it is giving. Further, when the transfer operation is executed only in the conversion period or when the transfer operation is executed only in the read period, the image data is deteriorated or the frame rate is lowered due to the occurrence of the remaining transfer of the image data.

Therefore, as shown in FIG. 3, the transfer operation is performed in parallel during the reading period of the radiography apparatus 101. At that time, the transfer operation of the radiography apparatus 101 to transfer to the external device is an image transfer operation of transferring the image data when there is image data to be transferred to the external device, and a dummy transfer operation of transferring non-image data when there is no image data to be transferred. It becomes. In the transfer operation of FIG. 3, the hatched portion indicates that the dummy transfer operation is in progress. For the non-image data, an identifier indicating the non-image data may be added to the header portion of the data, or information for notifying the non-image data may be transmitted to transfer the non-image data. The non-image data is data for a dummy transfer operation for adjusting the power consumption of the communication module, and means dummy data as data other than the image data acquired by shooting, such as padding data of a predetermined pattern. As the dummy data, for example, data in which each bit is "0" is used.

Further, the non-image data in the dummy transfer operation does not need to be received by the irradiation control device 120 and the system control device 130. The non-image data received by the irradiation control device 120 and the system control device 130 is discarded after determining the data itself or the identifier indicating the non-image data in the header portion of the data. It is also possible to prevent the external device from receiving the non-image data by setting an address completely different from the address of the communication module of the external device as the data transmission destination of the non-image data.

FIG. 4 is a timing chart showing an operation of reading image data of the radiography apparatus 101 according to the first embodiment of the present invention and an operation of transferring image data to an external device.

The difference between FIG. 4 and the timing chart of FIG. 3 is that the dummy transfer operation is not only divided by time but also controlled by the amount of data. Even by the transfer operation in which the amount of data is controlled, it is possible to perform the transfer operation during the read operation in parallel.

FIG. 5 is a timing chart showing an operation of reading image data of the radiography apparatus 101 according to the first embodiment of the present invention and an operation of transferring image data to an external device.

The difference between FIG. 5 and the timing chart of FIG. 4 is that the transfer operation is not a constant transfer operation but changes with time during the read drive. Such a change with time of the transfer operation makes it possible to control the power consumption of the communication module, but the transfer operation is similar during each of the image data acquisition and offset data acquisition read operations.

As described above, the transfer control unit executes the dummy transfer operation of the communication unit so that the power consumption of the communication unit in the image data acquisition period and the image correction data acquisition period is substantially the same. Therefore, the fluctuation of the power consumption of the communication unit (communication module) is suppressed. As a result, deterioration of image quality in image transfer can be suppressed. The dummy transfer operation can be realized by a transfer operation by combining a transfer operation using image data and a dummy transfer operation using non-image data during the read operation. Further, the dummy transfer operation can be realized by the operation of the communication unit without transmitting data from the wireless module to the external device. Further, in order to make the power consumption of the communication unit substantially the same in the image data acquisition period and the image correction data acquisition period, the power consumption in the previously acquired data acquisition period is set as a target value. The transfer control unit can control and realize the power consumption during the acquisition period of the data to be acquired later. In addition to power consumption, the operation of the circuit of the communication unit can also be used as the control target.

Further, it is also possible to obtain an image with good image quality by controlling the fluctuation range of the power consumption in the acquisition period of the data acquired later with respect to the acquisition period of the data acquired earlier within a predetermined range. Then, in order to obtain good image quality, the power consumption of the communication unit at the time of reading the image correction data corresponding to the image data is substantially the same as the power consumption of the communication unit at the time of reading the image data. Operate the communication unit. The range of fluctuation range of the power consumption of the communication unit is preferably 50% or less. More preferably, the fluctuation range of the power consumption of the communication unit is 20% or less. This power consumption control can be executed because the storage unit 103 stores the power consumption of the communication unit during the read operation.

Further, when the transmission of image data is delayed during communication between the wireless communication unit 104 and the external device, the transfer control unit performs the communication unit so as to prioritize the transfer operation of the image data or the image correction data over the dummy transfer operation. To execute.

By lengthening the transfer operation in this way, it is possible to achieve both high speed of the frame rate of moving image shooting and suppression of deterioration of image quality in image transfer.

(Second embodiment)
Next, a second embodiment according to the present invention will be described. In the first embodiment, the configuration in which the image data of the radiography apparatus and the image correction data are read out alternately is described, but in the present embodiment, the image correction data is acquired before the image data is acquired.

FIG. 6 is a timing chart showing an operation of reading image data of the radiography apparatus 101 and an operation of transferring image data to an external device, and has a configuration in which offset data is acquired in advance as image correction data. The period for acquiring offset data is the calibration period, and the period for acquiring image data before correction is the shooting period.

The shooting sequence will be described with reference to FIG. During the calibration period, the radiography apparatus 101 repeatedly acquires offset data. During the offset data acquisition period, first, all the switch elements 208 of the sensor array 202 are turned off to shift the conversion element 209 to the storage drive, and the electric charge is accumulated in the conversion element 209. The operation shifts to the read-out drive, the switch element 208 is sequentially turned on by the operation of the image read-out control unit 108, and the offset data is read out from the conversion element 209. Then, the irradiation and the read-out operation are repeated for the next imaging. The offset accumulation drive and the read drive are repeated again to read the offset data. The communication module is transferred in parallel with the two offset data reading periods. Specifically, the radiography apparatus 101 performs a dummy transfer operation. When offset correction is performed by the radiography apparatus 101, the offset data obtained by averaging the two acquired offset data is stored in the storage unit 103. Although the number of offset data acquired in the present embodiment is two, a predetermined n images (n: 1 or more natural numbers) can be acquired. After that, during the imaging period, all the switch elements 208 of the sensor array 202 are turned off, the conversion element 209 is shifted to the storage drive, and the radiation detection unit 200 is irradiated with the radiation 115. Charges are accumulated in the conversion element 209 in response to the irradiation of the radiation 115. Next, the operation shifts to the read drive, and the switch element 208 is sequentially turned on by the operation of the image read control unit 108 to read the image data from the conversion element 209. The read image data is offset-corrected by the offset data stored in the storage unit 103 and transferred to the external device.

FIG. 7 is a timing chart showing the operation of reading the image data of the radiography apparatus 101 and the operation of transferring the image data to the external device, and has a configuration in which gain data is acquired in advance as image correction data. The period for acquiring gain data is the calibration period, and the period for acquiring image data before correction is the shooting period. Gain data can be obtained by irradiating radiation without arranging the subject 116.

The shooting sequence will be described with reference to FIG. 7. During the calibration period, the radiography apparatus 101 repeatedly acquires gain data. During the calibration period, first, all the switch elements 208 of the sensor array 202 are turned off, the conversion element 209 is shifted to the storage drive, and the radiation detection unit 200 is irradiated with the radiation 115. Charges are accumulated in the conversion element 209 in response to the irradiation of the radiation 115. Next, the process shifts to the read drive, and the switch element 208 is sequentially turned on by the operation of the image read control unit 108 to read the gain data from the conversion element 209. The gain accumulation drive and the read drive are repeated again to read the gain data. The communication module is transferred in parallel with the two gain data reading periods. When the gain is corrected by the radiography apparatus 101, the gain data obtained by averaging the two acquired gain data is stored in the storage unit 103. Although the number of offset data acquired in the present embodiment is two, a predetermined n images (n: 1 or more natural numbers) can be acquired. During the calibration period, offset data is acquired and offset correction is performed on the gain data. Therefore, from the gain data, fluctuation components affected by the environment such as temperature are reduced, and only the input / output gain characteristics of the conversion element are recorded. After that, during the imaging period, all the switch elements 208 of the sensor array 202 are turned off, the conversion element 209 is shifted to the storage drive, and the radiation detection unit 200 is irradiated with the radiation 115. Charges are accumulated in the conversion element 209 in response to the irradiation of the radiation 115. Next, the operation shifts to the read drive, and the switch element 208 is sequentially turned on by the operation of the image read control unit 108 to read the image data from the conversion element 209. The read image data is image-corrected using the offset data and the gain data stored in the storage unit 103, and transferred to an external device.

When the offset correction and the gain correction are processed in the radiography apparatus 101, the offset data and the gain data are stored in the radiography apparatus 101, but when the offset data and the gain data are processed in the radiography apparatus 101, the image correction data is subjected to the radiography. It is transmitted from the device 101 to an external device. In this case, the radiography apparatus 101 transfers the image data before correction to the external apparatus. It is also possible to perform offset correction in the radiography apparatus 101 and gain correction in an external device.

As described above, when the image correction data is acquired during the calibration period, the dummy transfer operation using the non-image data is performed in parallel to suppress the fluctuation of the power consumption of the communication module and reduce the image quality in the image transfer. Can be suppressed.

(Third Embodiment)
Next, a third embodiment according to the present invention will be described. In the above-described embodiment, the configuration in which the transfer operation is performed in parallel using at least one of the image data and the non-image data during the reading period of the radiography apparatus 101 has been described, but in the dummy transfer operation of the present embodiment, the data Adjust the current consumption of the communication module, not the transfer.

FIG. 8 is a block diagram showing the radiographic apparatus of the present embodiment, and is different from the radiographic apparatus of FIG. 1 in that it has a dummy circuit unit for adjusting the current consumption of the communication module.

The wireless communication unit 104 and the wired communication unit 105 are each connected to a dummy circuit unit, and the dummy circuit is operated to suppress fluctuations in the power consumption of the communication module during the transfer operation. The dummy circuit 301 has a transistor, an amplifier circuit, and the like, and by operating these circuit elements, power is consumed to control the power consumption as a communication module. Although the dummy circuit 301 has been shown to be connected to the wireless communication unit 104 and the wired communication unit 105, a dummy circuit may be configured inside each communication unit.

As described above, the power consumption of the dummy circuit can suppress fluctuations in the power consumption of the communication module and suppress deterioration of image quality in image transfer.

(Other embodiments)
The present invention supplies a program that realizes one or more functions of the above-described embodiment to a system or device via a network or storage medium, and one or more processors in the computer of the system or device reads and executes the program. It can also be realized by the processing to be performed. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

101 Radiation imaging device 102 Imaging control unit 103 Storage unit 104 Wireless communication unit 105 Wired communication unit 106 Power supply control unit 107 Battery 200 Radiation detection unit

Claims (13)

A radiation detector with multiple pixels and
A reading unit that reads out image data based on the output of the plurality of pixels and image correction data for correcting the image data from the radiation detection unit.
Communication unit that communicates with external devices
A transfer control unit that executes a dummy transfer operation of the communication unit so that the power consumption of the communication unit in the image data acquisition period and the image correction data acquisition period is substantially the same.
A radiography apparatus characterized by having. The radiography apparatus according to claim 1, wherein the dummy transfer operation is a transfer operation in which the communication unit transmits non-image data different from the image data and the image correction data. The radiography apparatus according to claim 1, further comprising a dummy circuit unit so that the power consumption of the communication unit is substantially the same, and the dummy transfer operation is an operation of the dummy circuit unit. .. The feature is that the fluctuation range of the power consumption of the communication unit at the time of reading the image correction data corresponding to the image data is 50% or less with respect to the power consumption of the communication unit at the time of reading the image data. The radiography apparatus according to any one of claims 1 to 3. The feature is that the fluctuation range of the power consumption of the communication unit at the time of reading the image correction data corresponding to the image data is 20% or less with respect to the power consumption of the communication unit at the time of reading the image data. The radiography apparatus according to any one of claims 1 to 3. The radiography apparatus according to any one of claims 1 to 5, wherein the image correction data is offset data read from the plurality of pixels in a state where no radiation is applied. The radiography apparatus according to any one of claims 1 to 5, wherein the image correction data is gain data read from the plurality of pixels in a state of being incident without arranging a subject. When the communication unit is a wireless communication unit and transmission from the wireless communication unit is delayed, the transfer control unit executes the transfer operation of the image data or the image correction data to the communication unit from the dummy transfer operation. The radiographing apparatus according to any one of claims 1 to 7, wherein the radiographing apparatus is used. It further has a storage unit for storing the image correction data, and has a storage unit.
Any of claims 1 to 8, wherein the transfer control unit causes the communication unit to execute a transfer operation of the corrected image data obtained by correcting the image data with the image correction data stored in the storage unit. The radiography apparatus according to item 1. The radiation photographing apparatus according to any one of claims 1 to 9, wherein the reading unit acquires the image data and the image correction data from the radiation detecting unit by photographing a moving image. A system control device that communicates with the radiography device,
A radiological imaging system comprising the radiographic imaging apparatus according to any one of claims 1 to 10. A program for operating a computer as each means of the radiography apparatus according to any one of claims 1 to 11. A radiation detector with multiple pixels and
A reading unit that reads out image data based on the output of the plurality of pixels and image correction data for correcting the image data from the radiation detection unit.
It is a control method of a radiography apparatus including a communication unit that communicates with an external device.
A step of storing the power consumption of at least one of the image data acquisition period and the image correction data acquisition period, and the step of storing the power consumption of the communication unit.
A step of executing a dummy transfer operation of the communication unit so that the power consumption of the communication unit in the image data acquisition period and the image correction data acquisition period is substantially the same.
A method for controlling a radiography apparatus, which comprises.

Images