JP6711595B2 - Radiation imaging apparatus, control apparatus, radiation imaging system, and method of controlling radiation imaging system - Google Patents

Description

The present invention relates to a radiation imaging apparatus, a control apparatus, a radiation imaging system, and a radiation imaging system control method.

A radiation imaging apparatus using a sensor that detects radiation such as X-rays is widely used in fields such as industrial and medical fields. In recent years, a multifunctional radiation imaging apparatus has been studied. As one of them, it is considered to incorporate a function of monitoring radiation irradiation. With this function, for example, it is possible to detect the timing when the irradiation of the radiation from the radiation source is started, the timing when the irradiation of the radiation should be stopped, and the irradiation dose or the cumulative irradiation dose. Automatic exposure control (AEC) is performed by detecting the cumulative dose of radiation that has passed through the subject and stopping the irradiation of radiation by the radiation source when the detected cumulative dose reaches a proper dose. Will also be possible.

Patent Document 1 discloses an example of a radiation imaging system that performs AEC using wireless communication between a radiation imaging apparatus having a built-in radiation dose detection sensor and a radiation generation apparatus.

JP, 2013-162963, A

The wireless communication environment greatly changes due to noise generated by the operation of other wireless communication devices and medical devices (such as a microwave therapy device). That is, the wireless communication environment is not always stable, and an unstable state such as disconnection of wireless communication due to noise generated in the surroundings or low communication speed may occur. However, although the radiation imaging system of Patent Document 1 performs AEC using wireless communication, no measures are taken against such a case. Therefore, the conventional radiation imaging system may not be able to stop the radiation irradiation at an appropriate timing when the wireless communication environment becomes unstable.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an advantageous technique for improving the stability of AEC using wireless communication.

The radiation imaging system of the present invention is capable of wirelessly communicating with a radiation imaging apparatus that detects radiation emitted from a radiation source, and a control unit that controls irradiation of radiation from the radiation source. And a display control device capable of wirelessly receiving radiation image data generated by the radiation imaging device based on the radiation emitted from the radiation source. The radiation imaging apparatus includes a first wireless communication unit and a second wireless communication unit that perform wireless communication by using frequency bands different from each other. And the selection unit selects the most stable first frequency band among the frequency bands that can be used in the first wireless communication unit, and can use the first frequency band in the second wireless communication unit. The most stable second frequency band is selected from the frequency bands, and the more stable first frequency band is controlled as a result of comparing the first frequency band and the second frequency band. A frequency band for wireless communication with a display unit, the second frequency band for a frequency band for communication with the display control device, and the radiation imaging device selects the result of detection of the radiation by the selection unit. The radiation image data is transmitted in the first frequency band of the selected first wireless communication unit, and the radiation image data is displayed in the second frequency band of the second wireless communication unit selected by the selection unit. It transmits to a control device, the control unit controls irradiation of radiation based on the detection result, and the display control device receives the radiation image data.

To provide an advantageous technique for improving the stability of AEC using wireless communication.

It is a figure which shows the radiation imaging system in 1st embodiment. It is a figure which shows the radiation imaging device in 1st embodiment. It is a figure which shows the control part in the radiation imaging device in 1st embodiment. 6 is a flowchart showing a frequency band switching operation in the first embodiment. It is a flowchart which shows the switching operation of the frequency band in 3rd embodiment. It is a figure which shows the radiation imaging system in 5th embodiment. It is a figure which shows the radiation imaging system in 5th embodiment. It is a figure which shows the radiation imaging system in 6th embodiment.

(First embodiment)
The radiation imaging system of each embodiment will be described below with reference to the drawings. FIG. 1 is a diagram showing a radiation imaging system according to the first embodiment.

As shown in FIG. 1, the radiation imaging system 10 is provided in a radiation room 1 for performing radiation imaging by irradiation of radiation and a control room 2 installed near the radiation room 1.

The radiation chamber 1 includes a radiation imaging apparatus 300, a first access point 320, a second access point 321, a switching HUB 323, a radiation generation device 324, and a radiation source 325 as the radiation imaging system 10. The radiation chamber 1 further includes an entry device 322, an AP communication cable 326, and a radiation generator communication cable 327.

The control room 2 includes, as the radiation imaging system 10, a control device 310, a radiation irradiation switch 311, a display device 313, an input device 314, a hospital LAN 315, and a radiation room communication cable 316.

The radiation imaging apparatus 300 includes a power supply control unit 301 including a battery and the like, a short-range wireless communication unit 302, a registration switch 303, a first wireless communication unit 304, and a second wireless communication unit 305. The radiation imaging apparatus 300 detects radiation that has passed through the subject 313 and generates radiation image data.

The first access point 320 and the second access point 321 are access points that perform wireless communication using different frequency bands, and perform wireless communication with the radiation imaging apparatus 300. In the radiation imaging system 10, each access point 320, 321 can be used to relay communication between the radiation imaging apparatus 300 and the control apparatus 310 and the radiation generation apparatus 324. In the present embodiment, as an example, the first access point 320 communicates using the 5 GHz band of the wireless LAN, and the second access point 321 communicates using the 2.4 GHz band of the wireless LAN.

The entry device 322 performs short-range wireless communication with the radiation imaging device 300. The switching HUB 323 controls the first access point 320, the second access point 321, the radiation generation device 324, and the control device 310 so that they can communicate with each other.

The radiation generator 324 controls the radiation source 325 to irradiate the subject 306 with radiation. The radiation generation device 324 generates radiation based on a radiation source control unit 3241 that controls the radiation source 325 so as to irradiate the radiation based on a predetermined condition, and a signal from the radiation imaging device 300 that indicates the start or stop of the irradiation. And a generation control unit 3242 for controlling the operation. The radiation source control unit 3241 and the generation control unit 3242 may be separate devices.

The AP communication cable 326 is a cable for connecting the first access point 320 and the second access point 321 to the switching HUB 323. The radiation generator communication cable 327 is a cable for connecting the radiation generator 324 and the switching HUB 323.

The control device 310 communicates with the radiation generation device 324 (generation control unit 3242) and the radiation imaging device 300 via the switching HUB 323, the first access point 320, and the second access point 321, and the radiation imaging system 10 is connected. Take overall control.

The radiation irradiation switch 311 is operated by the operator 312 to input radiation irradiation timing. The input device 314 is a device that inputs an instruction from the operator 312, and various input devices such as a keyboard and a touch panel are used. The display device 313 is a device that displays image-processed radiation image data and GUI, and a display or the like is used. The in-hospital LAN 315 is a backbone network in the hospital. The radiation room communication cable 316 is a cable for connecting the control device 310 to the switching HUB 323 and the entry device 322 in the radiation room 1.
Next, the operation of the radiation imaging system 10 will be described.

First, the operator 312 performs registration work of the radiation imaging apparatus 300 in the radiation imaging system.

When the operator 312 presses the registration switch 303 of the radiation imaging apparatus 300, short-range wireless communication is started between the short-range wireless communication unit 302 of the radiation imaging apparatus 300 and the entry device 322.

The control device 310 transmits the wireless connection related information of the first access point 320 and the second access point 321 to the radiation imaging apparatus 300 via the short-range wireless communication of the entry device 322. In the case of a wireless LAN, for example, the wireless connection related information includes a communication method such as IEEE 802.11n, a physical channel, an ESSID, an encryption key, and the like.

The radiation imaging apparatus 300 sets the first wireless communication unit 304 and the second wireless communication unit 305 according to the received wireless LAN connection related information. With this setting, the radiation imaging apparatus 300 establishes a wireless communication connection between the first access point 320 and the first wireless communication unit 304, and the second access point 321 and the second wireless communication unit 305.

Next, the operator 312 inputs the subject's information such as the ID, name, and date of birth of the subject 306 and the imaging region of the subject 306 to the control device 310. After inputting the imaging region, the operator 312 fixes the posture of the subject 306 and the radiation imaging apparatus 300.

When the preparation for imaging is completed, the operator 312 presses the radiation irradiation switch 311. When the radiation irradiation switch 311 is pressed, radiation is emitted from the radiation source 325 toward the subject 306.

The radiation imaging apparatus 300 wirelessly communicates with the radiation generator 324 (generation controller 3242) to control the start and end of radiation irradiation. The radiation applied to the subject 306 passes through the subject 306 and enters the radiation imaging apparatus 300. The radiation imaging apparatus 300 converts incident radiation into visible light and then detects it as a radiation image signal with a photoelectric conversion element.

The radiation imaging apparatus 300 drives a photoelectric conversion element to read a radiation image signal, and an AD conversion circuit converts an analog signal into a digital signal to obtain digital radiation image data. The obtained digital radiation image data is transferred from the radiation imaging apparatus 300 to the control device 310 by wireless communication.

The control device 310 performs image processing on the received digital radiation image data. The control device 310 displays a radiation image based on the image-processed radiation image data on the display device 313. The control device 310 functions as an image processing device and a display control device.

The above is the operation of the radiation imaging system after the operator 312 registers the radiation imaging apparatus 300 in the radiation imaging system until the radiation image of the subject 306 is displayed on the display device 313.

FIG. 2 is a diagram showing the radiation imaging apparatus 300.

As shown in FIG. 2, the radiation imaging apparatus 300 has a radiation detector 100. The radiation detector 100 has a function of detecting the applied radiation. The radiation detector 100 has a plurality of pixels arranged to form a plurality of rows and a plurality of columns. In the following description, an area in which a plurality of pixels is arranged in the radiation detector 100 is an imaging area.
The plurality of pixels include a plurality of imaging pixels 101 for acquiring a radiation image and a detection pixel 121 for monitoring irradiation of radiation.

The imaging pixel 101 includes a first conversion element 102 that converts radiation into an electric signal and a first switch 103 that is arranged between the column signal line 106 and the first conversion element 102.
The detection pixel 121 includes a second conversion element 122 that converts radiation into an electric signal and a second switch 123 that is arranged between the detection signal line 125 and the second conversion element 122.
The detection pixels 121 are arranged in the same column as a part of the plurality of imaging pixels 101.

The first conversion element 102 and the second conversion element 122 are composed of a scintillator that converts radiation into light and a photoelectric conversion element that converts light into an electric signal. The scintillator is generally formed in a sheet shape so as to cover the imaging region, and is shared by a plurality of pixels. Alternatively, the first conversion element 102 and the second conversion element 122 are composed of conversion elements that directly convert radiation into light.

The first switch 103 and the second switch 123 include, for example, a thin film transistor (TFT) whose active region is made of a semiconductor such as amorphous silicon or polycrystalline silicon (preferably polycrystalline silicon).

The radiation imaging apparatus 300 has a plurality of column signal lines 106 and a plurality of drive lines 104. Each column signal line 106 corresponds to one of the plurality of columns in the imaging region. Each drive line 104 corresponds to one of the plurality of rows in the imaging area. Each drive line 104 is driven by the drive circuit 221.

The first electrode of the first conversion element 102 is connected to the first main electrode of the first switch 103, and the second electrode of the first conversion element 102 is connected to the bias line 108. Here, one bias line 108 extends in the column direction and is commonly connected to the second electrodes of the plurality of conversion elements 102 arranged in the column direction.

The bias line 108 receives the bias voltage Vs from the element power supply circuit 226. The bias voltage Vs is supplied from the element power supply circuit 226. The power supply control unit 301 includes a battery, a DCDC converter, and the like. The power supply control unit 301 includes an element power supply circuit 226, and generates an analog circuit power supply and a digital circuit power supply that performs drive control, wireless communication, and the like.

The second main electrodes of the first switches 103 of the plurality of imaging pixels 101 that form one column are connected to one column signal line 106. The control electrodes of the first switches 103 of the plurality of image pickup pixels 101 forming one row are connected to one drive line 104. The plurality of column signal lines 106 are connected to the read circuit 222. Here, the read circuit 222 includes a plurality of detection units 132, a multiplexer 134, and an analog-digital converter (hereinafter, AD converter) 136.
Each of the plurality of column signal lines 106 is connected to the corresponding detection unit 132 of the plurality of detection units 132 of the read circuit 222. Here, one column signal line 106 corresponds to one detection unit 132. The detection unit 132 includes, for example, a differential amplifier. The multiplexer 134 selects the plurality of detection units 132 in a predetermined order and supplies the signal from the selected detection unit 132 to the AD converter 136. The AD converter 136 converts the supplied signal into a digital signal and outputs it.

The first electrode of the second conversion element 122 is connected to the first main electrode of the second switch 123, and the second electrode of the second conversion element 122 is connected to the bias line 108. The second main electrode of the second switch 123 is connected to the detection signal line 125. The control electrode of the second switch 123 is electrically connected to the drive line 124.

The radiation imaging apparatus 300 has a plurality of detection signal lines 125. One or more detection pixels 121 are connected to one detection signal line 125. The drive line 124 is driven by the drive circuit 241. One drive line 124 is connected to one or more detection pixels 121. The detection signal line 125 is connected to the reading circuit 242. Here, the reading circuit 242 includes a plurality of detection units 142, a multiplexer 144, and an AD converter 146.

Each of the plurality of detection signal lines 125 is connected to the corresponding detection unit 142 of the plurality of detection units 142 of the reading circuit 242. Here, one detection signal line 125 corresponds to one detection unit 142. The detection unit 142 includes, for example, a differential amplifier. The multiplexer 144 selects the plurality of detection units 142 in a predetermined order, and supplies the signals from the selected detection units 142 to the AD converter 146. The AD converter 146 converts the supplied signal into a digital signal and outputs it. The output of the read circuit 242 (AD converter 146) is supplied to the signal processing unit 224 and processed by the signal processing unit 224. The signal processing unit 224 outputs information indicating irradiation of radiation to the radiation imaging apparatus 300 based on the output of the reading circuit 242 (AD converter 146). Specifically, the signal processing unit 224 detects, for example, irradiation of the radiation imaging apparatus 300 with radiation, and calculates the irradiation amount and/or integrated irradiation amount of radiation.

The control unit 225 controls the drive circuit 221, the drive circuit 241, the read circuits 222, 242, and the like based on the information from the signal processing unit 224 and the control command from the control device 310.

Next, a dose control operation of the radiation imaging system 10 using the radiation imaging apparatus 300 will be described.

The operator 312 inputs into the control device 310 a dose, a maximum irradiation time, a tube current, a tube voltage, a radiation detection area (ROI) that is an area where radiation should be monitored, site information, and the like. The control device 310 transmits the input radiation irradiation conditions, the radiation detection region (ROI), the region information, and the like to the radiation imaging device 300 and the radiation generation device 324 (generation control unit 3242). When the operator 312 presses the radiation irradiation switch 311 after the preparation for photographing is completed, the radiation is emitted. The applied radiation passes through the subject 306 and enters the radiation imaging apparatus 300. The radiation imaging apparatus 300 detects the radiation that has entered the radiation detection area (ROI) with the detection pixel 121, and calculates the integrated irradiation amount that is the integrated value of the dose (arrival dose) detected in the predetermined transfer of the signal processing unit 224. .. Here, the control unit 225 calculates an appropriate dose from the integrated dose information from the signal processing unit 224, the site information input by the operator 312, the imaging conditions, and the like, and determines the radiation irradiation stop timing. The radiation imaging apparatus 300 notifies the radiation generation apparatus 324 of the stop by wireless communication based on the determined radiation irradiation stop timing. The radiation generator 324 (generation controller 3242) stops irradiation of radiation based on the notified irradiation irradiation stop timing. Note that the radiation imaging apparatus 300 notifies the stop of radiation irradiation as a detection result of detecting radiation, but is not limited to this. The radiation imaging apparatus 300 may transmit the arrival dose at every predetermined time as a detection result, and the radiation generation apparatus 324 (generation controller 3242) may calculate the integrated value of the arrival dose.

The subsequent operation is the same as the operation of the radiation imaging system described above.

FIG. 3 is a diagram showing the control unit 225 of the radiation imaging apparatus 300. As shown in FIG. 3, the control unit 225 includes a drive control unit 400, a CPU 401, a memory 402, a radiation generation device control unit 403, and an image data control unit 404. The control unit 225 further
The communication switching unit 405, the registration switch 303, the short-range wireless communication unit 302, the first wireless communication unit 304, and the second wireless communication unit 305 are provided.

The drive control unit 400 controls the drive circuit 221, the drive circuit 241, and the read circuit 222 based on the information from the signal processing unit 224 and the command from the control device 310. The CPU 401 uses the programs and various data stored in the memory 402 to control the entire radiation imaging apparatus 300. The memory 402 stores, for example, programs and various data used when the CPU 401 executes processing. The memory 402 also stores various data obtained by the processing of the CPU 401 and radiation image data. The short-range wireless communication unit 302 performs short-range wireless communication with the entry device 322. The registration switch 303 is a switch for starting short-range wireless communication with the entry device 322.

The first wireless communication unit 304 communicates with the first access point 320. The first wireless communication unit 304 is configured to be able to measure the wireless communication environment. In this case, the first wireless communication unit 304 can function as a measurement unit for acquiring the parameter indicating the wireless communication environment. The first wireless communication unit 304 can measure the SNR, the data rate, the RSSI, which are parameters indicating the wireless communication environment of the frequency band being used, or the number of wireless devices using the band. The wireless communication unit 304 outputs the measurement result of the wireless communication environment parameter to the frequency selection unit 405.

The second wireless communication unit 305 communicates with the second access point 321. Similarly to the first wireless communication unit 304, the second wireless communication unit 305 measures the wireless communication environment parameter and outputs the measurement result to the communication switching control unit 405. In this case, the second wireless communication unit 305 can function as a measurement unit for acquiring the parameter indicating the wireless communication environment.

For example, the first wireless communication unit 304 and the first access point 320 communicate using the 5 GHz band of the wireless LAN, and the second wireless communication unit 305 communicates with the second access point 321 and the wireless LAN 2. Communication is performed using the 4 GHz band. The radiation generator control unit 403 controls wireless communication with the radiation generator 324 based on the information from the signal processor 224 and the information from the drive controller 400. The radiation generation device control unit 403 and the radiation generation device 324 exchange information regarding the control of the radiation generation device (for example, radiation irradiation start/stop notification, radiation irradiation amount, integrated irradiation amount, etc.). The image data control unit 404 saves the image data from the reading circuit 222 in the memory 402 and controls wireless communication with the control device 310. The image data control unit 404 and the control device 310 exchange radiation image data and information related to control (for example, control commands).

The frequency selection unit 405 controls switching of connection between the radiation generator control unit 403 and the image data control unit 404, and the first wireless communication unit 304 and the second wireless communication unit 305. Specifically, either the first wireless communication unit 304 or the second wireless communication unit 305, or both of them are allocated for communication of information relating to control of the radiation generation device handled by the radiation generation device control unit 403. To control. Similarly, for communication of image data handled by the image data control unit 404 or information relating to control, it is controlled whether to allocate either the first wireless communication unit 304 or the second wireless communication unit 305, or both. For example, when the first wireless communication unit 304 is assigned for communication of the radiation generator control unit 403, the second wireless communication unit 305 is assigned for communication of the image data control unit 404. The communication switching control unit 405 determines which wireless communication unit the radiation generation apparatus is to communicate with based on the measurement result of the wireless communication environment parameter measured by the first wireless communication unit 304 and the second wireless communication unit 305. It can also be assigned.

Note that the 2.4 GHz and 5 GHz bands are given as examples of the wireless frequency bands used by the first and second wireless communication units, but the present invention is not limited to this, and other wireless frequency bands (for example, 60 GHz band) may be used. However, different channels may be used in the same 5 GHz band. That is, the frequency band used for wireless communication may be different for each wireless communication unit. The functions of the radiation generator control unit 407, the image data control unit 408, and the frequency selection unit 405 may be executed by the CPU 401.

Here, the frequency band switching operation according to the present embodiment will be described with reference to the flowchart of FIG.

In S41, the radiation imaging apparatus 300 registers with the radiation imaging system 10.

In S42, the first wireless communication unit 304 and the second wireless communication unit 305 use the SNR, the data rate, the RSSI, which is the wireless communication environment parameter of the frequency band used by each, or the band. Measure the number of wireless devices in use. The measurement result of the wireless communication environment parameter is output to the frequency selection unit 405.

In S43, the frequency selection unit 405 is the most stable in the frequency band used by the first wireless communication unit 304 and the second wireless communication unit 305 based on the measurement result of the wireless communication environment parameter. Select a radio frequency band. For example, the frequency selection unit 405 may compare the SNRs of the wireless communication environment parameters and select the frequency band with the highest SNR. Further, the frequency selection unit 405 may compare the data rates and select the frequency band having the highest data rate. Further, the frequency selection unit 405 may select the frequency band having the largest RSSI. The frequency selection unit 405 also selects a frequency band in which the number of wireless devices using that band is the smallest. Further, the frequency selection unit 405 may compare and select two or more values of the plurality of wireless communication environment parameters.

In S44, the frequency selection unit 405 confirms whether the frequency band determined to be the most stable in S43 matches the frequency band used by the radiation generator control unit 403 for communication. If the frequency selection unit 405 matches the frequency band currently used by the radiation generation apparatus control unit 403, the processing is ended. If the frequency selection unit 405 does not match the frequency band used by the radiation generator control unit 403, the process proceeds to S45. The frequency selection unit 405 is currently using the first wireless communication unit 304 for communication of the radiation generator control unit 403, for example, and the most stable frequency band is used by the second wireless communication unit 305. If it is confirmed that the frequency band is within the specified frequency band, the process proceeds to S45.

In S45, the frequency selection unit 405 switches the frequency band used by the radiation generator control unit 403 based on the selection result in S43. A case where the first wireless communication unit 304 is used for communication of the radiation generator control unit 403 will be described. In this case, the frequency selection unit 405 selects the second wireless communication unit 305 for communication with the radiation generation device control unit 403. Then, the frequency selection unit 405 selects the first wireless communication unit 304 for communication of the image data control unit 404.

In S46, it is confirmed that wireless communication has been established by the designated communication means, and the switching process ends.

Although the configuration having the first and second wireless communication units has been described as an example of the wireless communication unit, the present invention is not limited to this, and the radiation imaging apparatus 300 includes three or more wireless communication units and the frequency selection unit. 405 may select the most stable frequency band among them.

The radiation imaging system 10 according to the first embodiment described above has the frequency determined to be most stable in the frequency band used by the first wireless communication unit 304 and the second wireless communication unit 305. The band is assigned exclusively to the radiation generator control unit 403. Therefore, the radiation imaging apparatus 300 can stably transmit the detected result. Then, since the radiation generation device 324 can perform wireless communication in a frequency band that is relatively more stable than other frequency bands, it is possible to stop irradiation of radiation at an appropriate timing. Therefore, the radiation imaging system 10 can prevent excessive radiation from being applied to the subject. Further, the radiation imaging system 10 can perform communication processing relating to control of the radiation generation device at higher speed by separating communication of radiation image data that requires a large amount of data communication and communication means.

(Second embodiment)
Next, a second embodiment will be described. In the first embodiment, the wireless communication environment parameter of the frequency band used by the first wireless communication unit 304 and the second wireless communication unit 305 is measured, and the most stable frequency band is controlled by the radiation generator. The example of assigning to the wireless communication of the unit 403 has been described. In the second embodiment, the wireless communication environment parameters of all frequency bands usable by the first wireless communication unit 304 and the second wireless communication unit 305 are measured. Then, the frequency selection unit 405 will describe a case where the most stable frequency band among them is assigned to the wireless communication of the radiation generation device control unit 403. In the following description, only the differences from the first embodiment will be described.

The flowchart of the frequency band switching operation according to the present embodiment is the same as in FIG. Here, only the differences from the first embodiment in each step will be described.

In S42, the first wireless communication unit 304 and the second wireless communication unit 305 measure wireless communication environment parameters of all usable bands. For example, the first wireless communication unit measures wireless communication environment parameters of all channels when channels 36 to 64 in the 5 GHz band of the wireless LAN are available. Similarly, the second wireless communication unit measures wireless communication environment parameters of all channels when channels 1 to 13 in the 2.4 GHz band of the wireless LAN are available.

In S43, the frequency selection unit 405 selects the most stable frequency band among the bands usable by the first wireless communication unit 304 and the second wireless communication unit 305. For example, if the most stable frequency band in the first wireless communication unit 304 is the channel 36, the frequency selection unit 405 selects the channel 36 as the frequency band of the first wireless communication unit. Similarly, when the most stable frequency band in the second wireless communication unit 305 is channel 1, the frequency selection unit 405 selects channel 1 as the frequency band of the second wireless communication unit. Next, the frequency selection unit 405 compares the frequency bands (channel 36 and channel 1) selected by the first wireless communication unit 304 and the second wireless communication unit 305, respectively. As a result of comparison, when the channel 36 of the first wireless communication unit is more stable, the frequency selection unit 405 selects the channel 36 of the first wireless communication unit as the most stable frequency band. .. That is, the frequency selection unit 405 selects the channel 36 of the first wireless communication unit 304 as the frequency band used by the radiation generation device control unit 403. Further, the frequency selection unit 405 selects the channel 1 of the second wireless communication unit 305 as the frequency band used by the image data control unit 404.

In S44, the frequency selection unit 405 confirms whether the selection result of S43 and the frequency band (channel) currently used by the radiation generator control unit 403 and the image data control unit 404 match. The frequency selection unit 405 ends the process when the frequency bands match, and proceeds to S45 when the frequency bands do not match.

In S45, the frequency selection unit 405 notifies the control device 310 of the selection result of S43, and switches the frequency band used by the radiation generation device control unit 403 based on the selection result of S43. Specifically, first, the control unit 310 is notified to change the channel used by the first access point 320 to the channel 36 and the channel used by the second access point 321 to the channel 1. The controller 310 changes the used channel of the first access point 320 to 36 and the used channel of the second access point 321 to 1. Next, the frequency selection unit 405 switches to the channel 36 of the first wireless communication unit 304 as the frequency band used by the radiation generation device control unit 403, and the second frequency band as the frequency band used by the image data control unit 404. Switch to channel 1 of the wireless communication unit 305.

The process after S46 is the same.

According to the above-described second embodiment, radiation is generated in the frequency band determined to be the most stable among the frequency bands usable by the first wireless communication unit 304 and the second wireless communication unit 305. It is assigned exclusively to the device control unit 403. Therefore, it is possible to perform relatively stable wireless communication as compared with the first embodiment.

(Third embodiment)
Next, a third embodiment will be described. In the first and second embodiments, the method in which the radiation imaging apparatus 300 measures the wireless communication environment parameter has been described. In the third embodiment, a procedure of measuring wireless communication environment parameters of all frequency bands usable by the access point and allocating the most stable frequency band among them to the wireless communication of the radiation generator control unit 403. Will be described. That is, in this embodiment, each access point functions as a measuring unit.

FIG. 5 is a flowchart showing an example of a wireless communication frequency band switching operation according to the third embodiment.

In S51, the wireless communication environment parameters of all the bands usable by the first access point 320 and the second access point 321 are measured. For example, when the first access point 320 can use the channels 36 to 64 in the 5 GHz band of the wireless LAN, the wireless communication environment parameters of all the channels are measured. Similarly, when the second access point 321 can use channels 1 to 13 in the 2.4 GHz band of the wireless LAN, the wireless communication environment parameters of all the channels are measured. The measurement result of the wireless communication environment parameter is output to control device 310. Each access point measures the wireless communication environment parameter every predetermined period. For example, each access point measures wireless communication environment parameters every 10 minutes. Since each access point can detect noise that occurs irregularly by performing the measurement every predetermined period, it is possible to measure the wireless communication environment parameter with higher reliability.

In S52, control device 310 determines the most stable frequency band among the bands usable by first access point 320 and second access point 321 based on the measurement result of the wireless communication environment parameter. Select. For example, when the most stable frequency band of the first access point 320 is the channel 36, the control device 310 selects the channel 36 as the frequency band of the first access point 320. Similarly, when the most stable frequency band of the second access point 321 is the channel 1, the control device 310 selects channel 1 as the frequency band of the second access point 321. Next, the control device 310 compares the channels (channel 36 and channel 1) selected by the first access point 320 and the second access point 321 respectively. When the channel 36 of the first access point 320 is more stable based on the comparison result, the control device 310 selects the channel 36 of the first access point 320 as the most stable frequency band. .. That is, the controller 310 selects the channel 36 of the first access point 320 as the frequency band used by the radiation generator controller 403. Further, the control device 310 selects the channel 1 of the second access point 321 as the frequency band used by the image data control unit 404.

In S53, the control device 310 reflects the result selected in S52 in the wireless connection related information and transmits it to the radiation imaging apparatus 300 via the entry device 322. Subsequently, the control device 310 also transmits information on the most stable frequency band (channel) of the first access point 320 and the second access point 321. Specifically, control device 310 transmits information designating channel 36 for the first access point and channel 1 for the second access point as the channel setting of the wireless connection related information. Subsequently, the control device 310 transmits the information of channel 1 as the most stable channel.

The radiation imaging apparatus 300 sets the first wireless communication unit 304 and the second wireless communication unit 305 based on the received wireless connection related information. That is, the radiation imaging apparatus 300 establishes a wireless communication connection between the first access point 320 and the first wireless communication unit 304, and the second access point 321 and the second wireless communication unit 305. Subsequently, the frequency selection unit 405 sets the frequency band used by the radiation generation device control unit 403 based on the information on the most stable frequency band obtained from the control device 310. Specifically, the first access point 320 and the first wireless communication unit 304 establish communication on the channel 36, and the second access point 321 and the second wireless communication unit 305 establish communication on the channel 1. .. Subsequently, the frequency selection unit 405 switches to the first wireless communication unit 304 that uses the channel 36 for communication of the radiation generation device control unit 403, and the second wireless communication unit for communication of the image data control unit 404. Switch to 305.

In S54, the frequency selection unit 405 confirms whether or not wireless communication is possible with the designated communication means, and ends the registration process.

In addition, although the configuration having two wireless communication means has been described as an example of the wireless communication means, the present invention is not limited to this, and the radiation imaging apparatus 300 includes three or more wireless communication means, and the frequency selection unit 405 includes the wireless communication means. The most stable frequency band may be selected. Further, the control device 310 uses the procedure of transmitting the result selected in S52 to the radiation imaging device 300, but transmits the measurement result of the wireless communication environment parameter to the radiation imaging device 300, and the radiation imaging device 300 is the most stable. The procedure for selecting the existing band may be used.

In the radiation imaging system 10 according to the third embodiment described above, the frequency band that is determined to be the most stable among the frequency bands that can be used by the first access point 320 and the second access point 321 is the radiation band. It is assigned exclusively to the generator control unit 403. Therefore, the radiation imaging system 10 can perform relatively stable wireless communication within the usable frequency band. Further, since the radiation imaging system 10 can periodically measure the wireless communication environment parameter before registration, it is possible to measure the wireless communication environment parameter with high accuracy. Further, in the radiation imaging system 10, since the frequency band to be used at the time of registration is known, the switching control at the time of registration can be simplified.

In the first, second, and third embodiments, the switching procedure of still image capturing is described, but the present invention is also applicable to a radiation imaging apparatus capable of capturing moving images such as fluoroscopy.

The automatic exposure control at the time of shooting a moving image is usually performed by a method of calculating the radiation dose for the next shooting using the taken radiation image data. Therefore, if the transmission of the radiation image data is delayed, the radiation dose necessary for the next imaging cannot be calculated, and thus the subject may be excessively exposed. Therefore, stable automatic exposure can be performed even in wireless video recording by transmitting information related to control of the radiation generator (eg, integrated dose information, irradiation start/stop timing, etc.) by stable wireless communication separately from the radiation image data. It becomes possible to control.

(Fourth embodiment)
Next, a fourth embodiment will be described.

In the fourth embodiment, the frequency selection unit 405 uses both the first wireless communication unit 304 and the second wireless communication unit 305 for communication with the radiation generation device control unit 403.

Similar to the first, second, and third embodiments, the first wireless communication unit 304 and the second wireless communication unit 305 establish communication in the most stable frequency band. The radiation imaging apparatus 300 simultaneously transmits information regarding control of the same radiation generation apparatus from the first wireless communication unit 304 and the second wireless communication unit 305. The radiation generator 324 controls the radiation generator 324 using the information received previously. When transmitting the radiation image data, different radiation image data is assigned to each of the first wireless communication unit 304 and the second wireless communication unit 305. By transmitting one radiation image data by two communication means, the radiation image data can be transmitted at high speed.

According to the fourth embodiment described above, even if one wireless communication is delayed due to the influence of noise or the like, the other communication can be covered, so that stable communication can be performed.

Although the configuration having two wireless communication means has been described as an example of the wireless communication means, the present invention is not limited to this, and even if the wireless communication means has three or more wireless communication means and three or more wireless communication means are used simultaneously. Good.

(Fifth Embodiment)
Next, a radiation imaging system according to the fifth embodiment will be described with reference to FIGS. Note that the same parts as those in the other embodiments are designated by the same reference numerals and the description thereof will be omitted.

The radiation imaging system 60 in the fifth embodiment is different from the other embodiments in the configuration of the access point. The radiation imaging apparatus 600 has at least one access point (first access point 604) built therein. The radiation imaging apparatus 600 can perform wireless communication with the control apparatus 310 via the wireless slave device 620 and the first access point 604. In this case, the radiation imaging apparatus 600 communicates with the radiation generator 324 (generation controller 3242) by the second wireless communication unit 305 via the second access point 321.

By incorporating the first access point 321 in the radiation imaging apparatus 600, the wireless communication environment parameter can be measured before registration, as shown in the third embodiment. Then, the communication switching control unit 405 can immediately obtain the measurement result of the wireless communication environment parameter without using communication such as close proximity wireless communication. Therefore, the radiation imaging system 60 can speed up a series of processes from the measurement of the wireless communication environment parameter to the selection of the frequency band.

The communication combination is not limited to the above configuration. For example, the radiation imaging apparatus 600 performs wireless communication with the radiation generation apparatus 324 via the wireless slave device 620 and the first access point 604, and by the second wireless communication unit 305 via the second access point 321. It may be configured to communicate with the control device 310.

Further, the number of access points built in the radiation imaging apparatus is not limited to one. As shown in the radiation imaging system 70 shown in FIG. 7, the radiation imaging apparatus 700 may include a plurality of access points 604 and 605.

Further, in order to be compatible with various radiation imaging systems, the radiation imaging apparatus may have a configuration in which it is possible to select which of an access point and a station (child device) performs wireless communication.

According to the fifth embodiment described above, stable communication can be performed even if the radiation imaging apparatus has a built-in access point.

(Sixth embodiment)
Next, a radiation imaging system 80 according to the sixth embodiment will be described with reference to FIG. The radiation imaging system 80 of the present embodiment does not have a switching HUB, and the control device 310 and the radiation generation device 324 are connected to dedicated wireless slave devices (720, 721), respectively. Furthermore, the radiation imaging apparatus 800 has one built-in access point 704. The first wireless slave device 720 and the second wireless slave device 721 are compatible with the 2,4 GHz band or the 5 GHz band. The access point 704 is also compatible with the 2,4 GHz band or the 5 GHz band. Therefore, like the other embodiments, the radiation imaging system 80 of the present embodiment can select a stable frequency band and wirelessly communicate with the control device 310 and the radiation generation device 324.

According to the sixth embodiment described above, stable communication can be performed even if the radiation imaging apparatus has a built-in access point.

In the radiation imaging system according to each embodiment, the configuration in which the radiation imaging apparatus itself has one or more access points built therein and the configuration in which the radiation imaging apparatus operates as a slave unit have been described. In the radiation image pickup system, the radiation image pickup apparatus may have a function of each of a master unit and a slave unit, and may be configured to be able to select which to operate. In the configuration, it is possible to select whether the radiation imaging apparatus operates as a master unit or a slave unit by inputting to the control device 310.

It should be noted that each embodiment can also be realized by a computer or a control computer executing a program (computer program). Further, means for supplying the program to the computer, for example, a computer-readable recording medium such as a CD-ROM storing the program or a transmission medium such as the Internet for transmitting the program can be applied as the embodiment. . The above program can also be applied as an embodiment. The above program, recording medium, transmission medium and program product are included in the scope of the present invention.

Although the detailed description has been given based on the embodiments above, the present invention is not limited to these specific embodiments, and various forms within the scope of the invention are also included in the scope of the present invention. Furthermore, the above-described embodiment is merely one embodiment, and an invention that can be easily imagined from the above-described embodiment is also included in the scope of the present invention.

10 Radiation Imaging System 100 Radiation Detector 225 Control Unit 300 Radiation Imaging Device 304 First Wireless Communication Unit 305 Second Wireless Communication Unit 310 Control Device 320 First Access Point 321 Second Access Point 324 Radiation Generation Device 325 Radiation Source 405 Frequency selection unit

Claims (10)

A radiation imaging device for detecting radiation emitted from a radiation source;
A control unit capable of wireless communication with the radiation imaging apparatus and controlling irradiation of radiation from the radiation source;
A display control device capable of wirelessly receiving radiation image data generated by the radiation imaging device based on radiation emitted from the radiation source;
A radiation imaging system comprising:
A selection unit for selecting a relatively stable frequency band based on the wireless communication environment,
The radiation imaging apparatus includes a first wireless communication unit and a second wireless communication unit that perform wireless communication using different frequency bands,
The selecting unit selects the most stable first frequency band from the frequency bands available in the first wireless communication unit, and selects the first stable frequency band from the frequency bands available in the second wireless communication unit. The most stable second frequency band is selected, and the more stable first frequency band is selected as a result of comparison between the first frequency band and the second frequency band, and Selecting as a frequency band for communication, selecting the second frequency band as a frequency band for communicating with the display control device,
The radiation imaging apparatus transmits a result of detecting the radiation to the control unit in the first frequency band of the first wireless communication unit selected by the selection unit, and the radiation image data is selected by the selection unit. Is transmitted to the display control device in the second frequency band of the second wireless communication unit selected by, the control unit controls irradiation of radiation based on the detection result, and the display control device A radiation imaging system, wherein the radiation image data is received. A measuring unit for measuring a parameter indicating a wireless communication environment of the plurality of wireless communication units,
The radiation imaging system according to claim 1, wherein the selection unit selects the frequency band based on a measurement result of the measurement unit. The radiation imaging system according to claim 2, wherein the parameter indicating the wireless communication environment is information related to the number of wireless devices using RSSI, SNR, data rate, or frequency band. Further comprising an access point that relays communication between the radiation imaging apparatus and the control unit,
The radiation imaging system according to claim 2, wherein the access point includes the measurement unit. The radiation imaging system according to claim 4, wherein the radiation imaging apparatus receives a parameter indicating a wireless communication environment measured by the access point. The selection unit selects a plurality of frequency bands that wirelessly communicate with the generation control unit,
The radiation imaging system according to claim 1, wherein the radiation imaging apparatus transmits a result of detecting the radiation in the selected plurality of frequency bands. The radiation imaging apparatus, in the plurality of frequency bands, simultaneously transmits the results of detecting the radiation,
The radiation imaging system according to claim 6, wherein the control unit controls irradiation of radiation from the radiation source using a detection result received earlier among the plurality of transmitted detection results. The radiation imaging apparatus has a radiation detector that detects the applied radiation,
The radiation detector includes an imaging pixel for acquiring a radiation image based on the irradiated radiation, and a detection pixel for acquiring a dose of the irradiated radiation. Radiation imaging system. It is possible to detect radiation emitted from the radiation source and wirelessly communicate with a control unit that controls irradiation of the radiation from the radiation source, and generate radiation image data generated based on the radiation emitted from the radiation source. A radiation imaging device capable of wirelessly transmitting to a display control device,
A selection unit that selects a relatively stable frequency band based on a wireless communication environment, and a first wireless communication unit and a second wireless communication unit that perform wireless communication using different frequency bands. ,
The selecting unit selects the most stable first frequency band from the frequency bands available in the first wireless communication unit, and selects the first stable frequency band from the frequency bands available in the second wireless communication unit. The most stable second frequency band is selected, and the more stable first frequency band is selected as a result of comparison between the first frequency band and the second frequency band, and Selecting as a frequency band for communication, selecting the second frequency band as a frequency band for communicating with the display control device,
The result of detecting the radiation is transmitted to the control unit in the first frequency band of the first wireless communication unit selected by the selection unit, and the radiation image data is selected by the selection unit. A radiographic imaging device transmitting to the display control device in the second frequency band of two wireless communication units. A radiation imaging device for detecting radiation emitted from a radiation source;
A control unit capable of wireless communication with the radiation imaging apparatus and controlling irradiation of radiation from the radiation source;
A display control device capable of wirelessly receiving radiation image data generated by the radiation imaging device based on radiation emitted from the radiation source;
A method for controlling a radiation imaging system comprising:
The radiation imaging system further includes a selection unit that selects a relatively stable frequency band based on a wireless communication environment,
The radiation imaging apparatus includes a first wireless communication unit and a second wireless communication unit that perform wireless communication using different frequency bands,
The selecting unit selects the most stable first frequency band from the frequency bands available in the first wireless communication unit, and selects the first stable frequency band from the frequency bands available in the second wireless communication unit. The most stable second frequency band is selected, and the more stable first frequency band is selected as a result of comparison between the first frequency band and the second frequency band, and Selecting as a frequency band for communication, selecting the second frequency band as a frequency band for communicating with the display control device,
The radiation imaging apparatus transmits the result of detecting the radiation in the first frequency band of the first wireless communication unit selected by the selection unit, and the radiation image data is selected by the selection unit. Transmitting to the display control device in the second frequency band of the second wireless communication unit,
The control method, wherein the control unit controls the radiation source based on the detection result, and the display control device receives the radiation image data.

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