JP2022164576A - Radiation imaging apparatus and radiation imaging system - Google Patents

Abstract

To obtain a satisfactory preview image while reducing the circuit scale of a read-out circuit.SOLUTION: In a radiation imaging system SYS, a radiation imaging apparatus 1 includes a plurality of pixels each including a conversion device, a drive circuit that controls the plurality of pixels, a bias source that supplies bias voltage to the conversion devices through bias lines, a detection unit that detects the presence or absence of radiation irradiation based on current flowing through the bias lines, and an image processing unit that generates data for images based on signals read out from the plurality of pixels. The plurality of pixels are divided into at least two pixel groups. Column signal lines are shared by the pixels that form two columns. While the detection unit detects the start of radiation irradiation, the drive circuit causes the plurality of pixels to sequentially perform a reset operation. After the end of the radiation irradiation, the image processing unit generates data for preview images from the signal for images output from the pixel group not including the pixels that performed the reset operation when the detection unit detected the radiation irradiation.SELECTED DRAWING: Figure 1

Description

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

2. Description of the Related Art Radiation imaging apparatuses using flat panel detectors (FPDs) made of semiconductor materials are widely used in medical image diagnosis and non-destructive inspection. In Patent Document 1, in order to synchronize with a radiation generating apparatus, when a radiation imaging apparatus is irradiated with radiation, a current (bias current) flows through a bias line that supplies a bias potential to pixels. A radiographic imaging device is shown that detects the presence or absence of irradiation of . Further, in Patent Document 1, reset scanning is repeated while irradiation of radiation is detected, and signals output from pixels other than the row selected when irradiation of radiation is detected after completion of irradiation of radiation are disclosed. is shown to generate preview image data based on .

JP 2014-194408 A

A readout circuit for reading out signals from a large number of pixels arranged in the FPD has an analog amplifier and an A/D converter arranged for each column signal line from which signals are read out from the pixels. It occupies a large proportion of the member cost of the imaging device.

SUMMARY OF THE INVENTION An object of the present invention is to provide an advantageous technique for obtaining a good preview image while suppressing the circuit scale of a readout circuit in a radiation imaging apparatus.

In view of the above problems, a radiation imaging apparatus according to an embodiment of the present invention includes a plurality of pixels each including a conversion element that converts radiation into an electric charge and arranged to form a plurality of rows and a plurality of columns; a drive circuit for controlling the plurality of pixels through a plurality of drive lines extending in the row direction; a bias source for supplying a bias voltage to the conversion element through a bias line; and a bias voltage flowing through the bias line. image data based on signals read from the plurality of pixels through a detection unit that detects the presence or absence of irradiation of radiation based on current; and a plurality of column signal lines arranged to extend in the column direction. an image processing unit that generates an image, wherein the plurality of pixels are divided into at least two pixel groups connected to mutually different drive lines among the plurality of drive lines, and the plurality of columns Each column signal line of the signal lines is shared by pixels forming two columns among the plurality of pixels, and the driving circuit is configured to drive the plurality of driving pixels while the detection unit detects the start of radiation irradiation. The plurality of pixels are sequentially reset via a line, and after irradiation of radiation is completed, the image processing unit performs a reset operation when the detection unit among the plurality of pixels detects irradiation of radiation. The present invention is characterized in that preview image data is generated from image signals output from pixel groups that do not include pixels that have already been processed.

By the means described above, in the radiographic imaging apparatus, a technology is provided that is advantageous for obtaining a good preview image while suppressing the circuit scale of the readout circuit.

1 is a block diagram showing a configuration example of a radiation imaging system using a radiation imaging apparatus according to this embodiment; FIG. FIG. 2 is a diagram showing a configuration example of the radiation imaging apparatus in FIG. 1; FIG. 2 is a flowchart for explaining the operation of a radiation imaging system using the radiation imaging apparatus of FIG. 1; FIG. 2 is a timing chart for explaining the operation of the radiation imaging apparatus in FIG. 1; FIG. 2 is a timing chart for explaining the operation of the radiation imaging apparatus in FIG. 1; FIG. 2 is a timing chart for explaining the operation of the radiation imaging apparatus in FIG. 1; FIG. 2 is a diagram showing a configuration example of a pixel that performs a reset operation of the radiation imaging apparatus of FIG. 1; FIG. 2 is a diagram showing a configuration example of pixels for preview image data of the radiation imaging apparatus in FIG. 1 ; FIG. 2 is a diagram showing a configuration example of a pixel that performs a reset operation of the radiation imaging apparatus of FIG. 1; FIG. 2 is a timing chart for explaining the operation of the radiation imaging apparatus in FIG. 1; FIG. 2 is a diagram showing a configuration example of a pixel that performs a reset operation of the radiation imaging apparatus of FIG. 1; FIG. 2 is a diagram showing a configuration example of pixels for preview image data of the radiation imaging apparatus in FIG. 1 ; FIG. 2 is a diagram showing a configuration example of a pixel that performs a reset operation of the radiation imaging apparatus of FIG. 1; FIG. 2 is a flowchart showing an operation example between the radiation imaging apparatus of FIG. 1 and a console;

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. In addition, the following embodiments do not limit the invention according to the scope of claims. Although multiple features are described in the embodiments, not all of these multiple features are essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant description is omitted.

Radiation in the present invention includes alpha rays, beta rays, and gamma rays, which are beams produced by particles (including photons) emitted by radioactive decay, as well as beams having energy equal to or higher than the same level, such as X rays. It can also include rays, particle rays, and cosmic rays.

The configuration and operation of the radiation imaging apparatus according to this embodiment will be described with reference to FIGS. FIG. 1 is a block diagram showing a configuration example of a radiation imaging system SYS using a radiation imaging apparatus 1 of this embodiment. The radiation imaging system SYS of this embodiment includes a radiation imaging device 1, a console 3 for controlling the radiation imaging device 1, a display unit 4, and a radiation generation unit 500 for irradiating radiation onto a subject.

The radiation imaging apparatus 1 includes a radiation detection unit 2 for detecting radiation and generating an image signal corresponding to incident radiation, a detection unit 101 for detecting the start and end of radiation irradiation, It includes an imaging control unit 102 that controls an imaging operation.

The imaging control unit 102 includes a drive circuit 103 that controls driving of the radiation detection unit 2 , a readout circuit 107 that performs control when reading image signals from the radiation detection unit 2 , and a readout circuit from pixels arranged in the radiation detection unit 2 . and an image processing unit 108 that generates image data based on the output signal. In addition, the imaging control unit 102 communicates with the console 3, such as by transferring the acquired image and the image data generated by the image processing unit 108 to the console 3, and the storage unit 111 that stores acquired images acquired from the radiation detection unit 2. It includes a communication control unit 114 that controls data communication between them. Wireless LAN communication, for example, can be used for communication between the radiation imaging apparatus 1 and the console 3 by the communication control unit 114 . However, the communication between the radiation imaging apparatus 1 and the console 3 is not limited to wireless LAN communication, and may be wireless communication using other methods or wired communication using a cable. .

The driving circuit 103 executes reset scanning control 105 for discharging accumulated dark charges (reset operation) of the radiation detection unit 2 periodically or at arbitrary timing. Further, the drive circuit 103 executes readout scanning control 106 that performs drive control for reading out an image from the radiation detection unit 2 . The drive circuit 103 also includes an irradiation detection time information storage unit 104 for storing information at the time of irradiation detection, such as the row number of the pixel row in which the reset operation was performed at the time the radiation irradiation was started.

The console 3 includes a communication control unit 301 that controls communication between the radiation imaging apparatus 1 and the console 3 such as receiving image data transferred from the radiation imaging apparatus 1 . The console 3 also includes a storage unit 302 for storing image data transferred from the radiation imaging apparatus 1 and a processing unit 303 for generating a signal for displaying an image on the display unit 4 from the image data. The processing unit 303 can be a processor that processes signals output from the radiation imaging apparatus 1 . For example, the processing unit 303 can perform signal processing for displaying image data transferred from the radiation imaging apparatus 1 to the console 3 on the display unit 4 as a radiation image. Further, for example, the processing unit 303 may perform correction processing on the image data when displaying the radiographic image on the display unit 4 .

The imaging control unit 102 may, for example, read a program or the like stored in the storage unit 111 and perform overall control of the radiation imaging apparatus 1 based on the read program. The radiation imaging apparatus 1 may be controlled by, for example, a control signal generating circuit (control circuit) such as an ASIC, or the overall control of the radiation imaging apparatus 1 is realized by both a program and a control circuit. may be

The radiation detection unit 2 includes a plurality of pixels arranged to form a plurality of rows and a plurality of columns, each including a conversion element that converts radiation into an electric charge. The drive circuit 103 controls a plurality of pixels through a plurality of drive lines arranged to extend in the row direction. For example, the radiation detection unit 2 can be configured by arranging a plurality of pixels in a two-dimensional array, with a combination of a switching element such as a TFT and a photoelectric conversion element as one pixel. For example, a scintillator is formed on the pixels. In this case, the radiation incident on the radiation detection unit 2 is converted by the scintillator into light of a wavelength convertible by the conversion element (for example, visible light). Light converted by the scintillator is incident on the photoelectric conversion element of each pixel, and the photoelectric conversion element generates an electric charge according to the incident light. In the present embodiment, an indirect conversion element that converts incident radiation into electric charges by means of the scintillator and photoelectric conversion element described above will be described as a configuration example. However, the conversion element is not limited to an indirect type element. For example, a so-called direct conversion type conversion element that directly converts incident radiation into charges without providing a scintillator may be used as the conversion element. The radiation detection unit 2 can acquire a radiographic image by storing and reading charges in pixels by switching ON (conducting state) and OFF (non-conducting state) of the switching elements.

FIG. 2 is a diagram showing a configuration example of the radiation detection unit 2. As shown in FIG. In the radiation detection unit 2 shown in FIG. 2, a pixel unit 212 having 6 rows×6 columns of pixels PIX is shown for simplification of explanation. However, more pixels PIX can be arranged in the actual pixel unit 212 . For example, about 3000 rows×about 3000 columns of pixels PIX can be arranged in the 17-inch pixel unit 212 .

The radiation detection unit 2 is a two-dimensional detector having a pixel unit 212 having a plurality of pixels PIX arranged in a matrix. The pixel PIX includes conversion elements S (S11 to S66) that convert radiation into charges, and switch elements T (T11 to T66) for outputting electrical signals corresponding to the charges generated by the conversion elements S. include. In this embodiment, the conversion element S includes a scintillator (wavelength conversion element) that converts irradiated radiation into light as described above, and a MIS or PIN photodiode that converts the light converted by the scintillator into charge. (Photoelectric conversion element) and are used. Further, as described above, the conversion element S may be a direct conversion element that directly converts radiation into electric charge. A transistor having a control terminal and two main terminals can be used as the switch element T. FIG. In this embodiment, the switching element T is a thin film transistor (TFT). One electrode of the conversion element S is electrically connected to one of two main terminals of the switch element T, and the other electrode is electrically connected to the bias source 203 via a common bias line Bs. In the configuration shown in FIG. 2, there are shown two systems, a bias source 203a connected via a bias line Bsa and a bias source 203b connected via a bias line Bsb. For example, when these two systems are not distinguished, they are described as bias source 203, and when one of them is specified, they are described as bias source 203a. If there are multiple elements in other constituent elements, they will be similarly shown below. The provision of two systems of the bias line Bs and the bias source 203 will be described later.

In the configuration shown in FIG. 2, a plurality of switch elements T arranged along the row direction, for example switch elements T11, T13, and T15, are driven out of a plurality of drive lines Vg arranged so as to extend in the row direction. The switch elements T12, T14 and T16 are connected to the drive line Vg1-2 among the plurality of drive lines Vg. In this way, the plurality of pixels PIX arranged in the pixel section 212 of the radiation detection section 2 are divided into at least two pixel groups connected to mutually different drive lines Vg among the plurality of drive lines Vg. In this embodiment, it can be said that the pixels PIX arranged along the row direction belong to one of the two pixel groups. Here, the row direction means the horizontal direction in FIG. Also, the column direction is a direction crossing the row direction, and indicates the vertical direction in FIG.

A signal generated by the pixel PIX is read out by the readout circuit 107 through a plurality of column signal lines Sig arranged to extend in the column direction, and transferred to the image processing unit 108 and the storage unit 111 described above. In the present embodiment, as shown in FIG. 2, each column signal line Sig of the plurality of column signal lines Sig is shared by the pixels PIX forming two columns among the plurality of pixels PIX. This makes it possible to reduce the circuit scale of the readout circuit 107, which will be described later, compared to the case where a column signal line is arranged for each pixel column.

In the present embodiment, as shown in FIG. 2, among the plurality of pixels PIX, the pixels PIX that are adjacent to each other in the row direction and share the same column signal line Sig among the plurality of column signal lines Sig are connected to each other. belong to different pixel groups. More specifically, a plurality of switch elements T arranged along the column direction, for example, the switch elements T11 and T12 of the pixels PIX belonging to different pixel groups are electrically connected to the column signal line Sig1. While the switch element T11 or the switch element T12 is in the conductive state, a signal corresponding to the charge generated in the conversion element S11 or the conversion element S12 is output to the readout circuit 107 via the column signal line Sig1. . Similarly, switch elements T21, T31, T41, T51, T61 and switch elements T22, T32, T42, T52, T62 are electrically connected to column signal line Sig1. The same applies to the switch elements T (pixels PIX) connected to the column signal lines Sig2 and Sig3. A plurality of signal wirings Sig arranged in the column direction transmit signals output from a plurality of pixels PIX to the readout circuit 107 in parallel.

The readout circuit 107 is provided with amplifier circuits 206 that amplify signals output in parallel from the pixel unit 212 so as to correspond to the respective column signal lines Sig. The amplifier circuit 206 includes an integral amplifier 205 that amplifies the signal output from the pixel PIX, a variable amplifier 204 that amplifies the output of the integral amplifier 205, and a sample and hold circuit 207 that samples and holds the electric signal amplified by the variable amplifier 204. include.

The integral amplifier 205 includes an operational amplifier that amplifies and outputs a signal read from the pixel PIX, an integral capacitor, and a reset switch. The integration amplifier 205 can change the amplification factor by changing the value of the integration capacitance. The signal output from the pixel PIX is input to the inverting input terminal of the operational amplifier of the integral amplifier 205, the reference voltage Vref is input from the reference power supply 211 to the non-inverting input terminal, and the amplified signal is output from the output terminal. be done. The integrating capacitor is placed between the inverting input terminal and the output terminal of the operational amplifier of integrating amplifier 205 . A sample hold circuit 207 is provided in each amplifier circuit 206 and includes a sampling switch and a sampling capacitor.

The reading circuit 107 also includes a multiplexer 208 that sequentially outputs the signals read out in parallel from the amplifier circuit 206 as serial signals, and a buffer amplifier 209 that converts the impedance of the serial signals output from the multiplexer 208 and outputs the signals. include. A signal Vout, which is an analog electrical signal output from the buffer amplifier 209 , is converted into a digital signal by the A/D converter 210 and supplied to the image processing unit 108 and the storage unit 111 .

A power supply unit (not shown) transforms power from a battery or an external source into a voltage corresponding to each power source, and supplies power to the reference power source 211 and bias source 203 shown in FIG. Reference power supply 211 supplies a reference voltage Vref to the non-inverting input terminal of the operational amplifier of integrating amplifier 205 . A bias source 203 commonly supplies a bias voltage Vs to the conversion elements S via a bias line Bs. Further, in the present embodiment, the bias source 203 outputs current information including temporal fluctuations in the amount of current supplied to the bias line Bs to the detection unit 101 . In this embodiment, the current-voltage conversion circuit 215 including an operational amplifier and a resistor is used as a circuit for outputting current information, but it is not limited to this configuration. For example, a current-voltage conversion circuit using a shunt resistor may be used as a circuit that outputs current information. Also, the circuit that outputs the current information may output the current information as a digital value using an A/D conversion circuit that converts the output voltage of the current-voltage conversion circuit into a digital value. Furthermore, the circuit that outputs current information may output a physical quantity corresponding to the amount of current supplied to the bias line Bs as current information.

The drive circuit 214 of the radiation detection unit 2 applies a conduction voltage Vcom for making the switch element T conductive and a non-conductive state in accordance with the control signals D-CLK, OE, and DIO input from the drive circuit 103 shown in FIG. A drive signal including a non-conducting voltage Vss to be set is output to each drive wiring Vg. Thereby, the drive circuit 214 controls the conducting state or the non-conducting state of the switch element T to drive each pixel PIX of the pixel section 212 .

Control signal D-CLK is a shift clock for a shift register that can be used as drive circuit 214 . The control signal DIO is a pulse transferred by the drive circuit 214 . The control signal OE is a signal that controls the output terminal of the drive circuit 214 . As described above, the driving circuit 103 sets the required driving time and the scanning direction of the pixel portion 212 via the driving circuit 214 . Drive circuit 103 also controls the operation of each component of read circuit 107 by providing control signals RC, SH, and CLK to read circuit 107 . Here, control signal RC controls the operation of the reset switch of integrating amplifier 205 . A control signal SH controls the operation of the sample and hold circuit 207 . Control signal CLK controls the operation of multiplexer 208 .

When the image signal converted into a digital value by the A/D converter 210 is a radiographic image signal obtained by irradiation with radiation, for example, this signal is stored in the captured image memory 112 of the storage unit 111. may In the case of an offset image signal obtained only from the dark charge component of each pixel PIX without radiation irradiation (hereinafter sometimes simply referred to as an offset image), the offset image signal is stored in the storage unit 111 may be stored in the offset image memory 113 of . The radiation image signal and the offset image signal may be subjected to signal processing such as correction processing by the image processing unit 108 and then stored in respective memories of the storage unit 111 . In addition, although the configuration shown in FIG. 1 is illustrated as if the captured image memory 112 and the offset image memory 113 are separately arranged in the storage unit 111, the configuration is limited to this. no. It is sufficient that the radiographic image signal and the offset image signal are stored in an appropriate storage (memory) area of the storage unit 111 .

The image processor 108 can include a preview image generator 109 and an offset corrector 110, as shown in FIG. The preview image generator 109 will be described later. The offset correction unit 110 functions as a processing unit that performs offset correction by subtracting an offset image component from a radiographic image signal. As a result, it is possible to prevent unnecessary dark charge components from being mixed into the radiographic image obtained, and to display a radiographic image with higher image quality on the display unit 4 . In the configuration shown in FIG. 1, the configuration of the preview image generation unit 109 and the offset correction unit 110 are separately arranged in the image processing unit 108, but the configuration is not limited to this. As long as preview image generation and offset correction are performed in the image processing unit 108, any configuration may be employed.

Next, with reference to FIG. 5A, an example of the driving timing of the detection unit 101 for detecting the start and end of radiation irradiation when detecting radiation irradiation will be described. Here, in the radiation imaging apparatus 1, a row Ys will be described as a row determined to start radiation irradiation. FIG. 5(a) is an enlarged view of the vicinity of the Ys row, which is the row where the start of radiation irradiation is determined.

FIG. 5A shows current information output from the bias source 203 for the detection unit 101 to output radiation information including temporal variations in the intensity of radiation incident on the pixel unit 212 . The detection unit 101 acquires radiation information from the information on the current flowing through the bias line Bs acquired from the bias source 203, and determines the start of radiation irradiation. That is, the detection unit 101 detects the start of radiation irradiation based on the signal output when the plurality of pixels PIX perform the reset operation. In FIG. 5A, radiation irradiation is started between the scanning of the Ys-1 row and the Ys row, and the information of the current flowing through the bias line Bs during the scanning of the Ys row exceeds the determination threshold, and the detection unit 101 , it is determined that radiation irradiation has started. According to the result of this determination, the drive circuit 103 shifts the pixels PIX to the accumulation operation for acquiring the radiographic image. However, as shown in FIG. 5B, when scanning the Ys row, the current information flowing through the bias line Bs may exceed the determination threshold due to external noise due to the impact or magnetic field. Therefore, in the example shown in FIG. 5(b), an impact is applied during the scanning of the Ys row during idle reading, the information on the current flowing through the bias line Bs exceeds the determination threshold value, and the detection unit 101 detects that the irradiation of radiation has not occurred. It will misjudge that it has started. According to this determination, the driving circuit 103 shifts the pixel PIX to the accumulation operation.

In order to detect the start of radiation irradiation, the detection unit 101 may directly use the sample value of the current signal flowing through the bias line Bs. However, in order to prevent an erroneous determination as shown in FIG. 5B, processing may be performed on the information on the currents flowing through the plurality of bias lines Bs so that the detector 101 detects irradiation of radiation. .

An example in which the detection unit 101 detects irradiation of radiation using information on currents flowing through a plurality of bias lines Bs will be described with reference to FIG. FIG. 6 shows a signal indicating that a current proportional to the dose of radiation per unit time flows through the bias line Bs during radiation irradiation. This current can flow more when the switch element T of the pixel PIX is in the ON (conducting) state than when it is in the OFF (non-conducting) state, but is shown as constant in the figure for simplicity. When the switch element T of the pixel PIX irradiated with radiation is turned on, a current proportional to the amount of charge accumulated in the conversion element S of the pixel PIX until the switch element T is turned on flows through the bias line Bs. This current is shown as the second signal in FIG. When an impact or a magnetic field is applied to the radiation imaging apparatus 1, a current corresponding to the frequency of noise applied to the bias line Bs may flow. This current is called extraneous noise and is shown as extraneous noise in FIG. For example, a current of about 50 to 60 Hz may flow through the bias line Bs under the influence of an electromagnetic field generated from a commercial power supply. Further, when an impact is input to the radiation imaging apparatus, a current of several Hz to several kHz may flow through the bias line Bs. In addition, internal noise such as switching noise of the switch element T and system noise can be considered, but they are omitted in FIG. 6 for the sake of simplification.

Also, as shown in FIG. 6, the drive cycle of the drive circuit 214 is represented by time TI. That is, the radiation imaging apparatus 1 performs a reset operation (idle reading) once every time TI. In the time TI, the drive circuit 214 supplies a high-level drive signal (a time in which the switch element T is in a conductive state) is represented by a time TH, time to be in a non-conducting state) is represented by time TL. Further, as shown in FIG. 6, the period during which the detection unit 101 samples the information on the current flowing through the bias lines Bsa and Bsb from the bias sources 203a and 203b is represented by time TS.

In the present embodiment, as shown in FIG. 2, the radiation detection unit 2 includes two bias sources 203, so that two pieces of information about the currents flowing through the bias lines Bsa and Bsb can be obtained simultaneously in one time TS. . Therefore, by taking the difference between the sample value S of the current information output by the pixel PIX whose switch element T is in the conducting state and the noise value N of the current information output by the pixel PIX whose switch element T is in the non-conducting state, External noise can be removed. As a result, the detection unit 101 can accurately extract the second signal caused by the current proportional to the amount of charge accumulated in the conversion element S of the pixel PIX due to the irradiation of the radiation until the switch element T is turned on. becomes.

That is, in the present embodiment, the bias sources 203a and 203b supply bias voltages to the conversion elements S via electrically independent bias lines Bsa and Bsb for each of at least two pixel groups. When detecting the start of radiation irradiation, the detection unit 101 detects current flowing through a bias line (here, bias line Bsa) connected to a pixel group including a pixel PIX that performs a reset operation among the plurality of pixels PIX. and the signal value representing the current flowing through the bias line Bsb connected to the pixel group that does not include the pixel PIX that performs the reset operation among the plurality of pixels PIX so that at least part of the sampling timing overlaps. to get to. The start of radiation irradiation is determined based on the signal value representing the current flowing through the bias line Bsa and the signal value representing the current flowing through the bias line Bsb. As a result, the detection unit 101 can prevent the noise shown in FIG. 5B from being detected as the start of radiation irradiation.

In the present embodiment, two independent drive lines Vg are connected to the pixels PIX arranged along the row direction, but one drive line Vg may be connected. In this case, one piece of current information is obtained in one time TS, and the timing of obtaining the sample value and the noise value are different, but the method of calculating the radiation information is the same. Further, for example, a configuration may be adopted in which sample values and noise values are simultaneously obtained from two rows adjacent to each other. In this case, the drive line Vg may be connected to each row of the pixels PIX, and the bias voltage Vs may be supplied from the bias source 203 through electrically independent bias lines Bs to the pixels PIX in adjacent rows. .

Further, when the detection unit 101 detects the start of irradiation of radiation, the driving circuit 214 connects a plurality of driving lines Vg to at least two driving lines Vg connected to the pixels PIX belonging to the same pixel group among the plurality of driving lines Vg. A signal for resetting the pixel PIX may be supplied at the same time. As a result, in one reset operation, a current proportional to the charges accumulated in the pixels PIX for an arbitrarily set row flows through the bias line Bs. As a result, the S/N ratio of the information on the current flowing through the bias line Bs can be improved. At this time, the drive lines Vg driven simultaneously may or may not be adjacent to each other. Further, the radiation imaging apparatus 1 may be configured such that, for example, the number of drive lines Vg that are simultaneously driven in the reset operation can be changed according to user's designation. In this case, as the number of drive lines Vg driven simultaneously increases, the switching noise of the switching element T also increases. may

Next, the preview image generator 109 will be described. A preview image generation unit 109 of the image processing unit 108 generates preview image data after capturing a radiographic image in order to improve usability for the user. The preview image is an image using signals output from some pixels PIX among the pixels PIX arranged in the pixel unit 212, and is displayed on the display unit 4 immediately after imaging to improve usability for the user. .

At this time, the image processing unit 108 performs processing including offset correction on the image signal based on the signals read from the plurality of pixels PIX without irradiating radiation, and generates preview image data. good too. The image signal from which unnecessary dark charge components have been removed may be reduced for the preview image.

For example, after the preview image generation unit 109 of the image processing unit 108 acquires the image signal, an offset image is acquired based on the signals read from the plurality of pixels PIX without irradiating radiation, and the image processing unit An offset correction unit 110 at 108 may perform offset correction based on the offset image. In this case, the offset image performs a reset operation when the detection unit 101 detects irradiation of radiation among the signals read from the plurality of pixels PIX without irradiating radiation. It may be composed of signals output from pixel groups that do not include pixels. As a result, the time required to obtain the offset image can be shortened compared to the case where signals are read out from all pixels PIX. The image processing unit 108 transfers the preview image data offset-corrected by the offset correction unit 110 to the console 3 under the control of the communication control unit 114 . The generated preview image is thereby displayed on the display unit 4 connected to the console 3 .

Further, for example, an offset image based on signals read from a plurality of pixels PIX without radiation may be stored in the offset image memory 113 of the storage unit 111 . The image processing unit 108 may perform offset correction based on the offset image stored in the offset image memory 113 . In the image processing unit 108 , the preview image generation unit 109 acquires the image signal output from the pixel unit 212 , and then performs an offset correction unit using one offset image stored in the offset image memory 113 of the storage unit 111 . 110 performs offset correction to generate preview image data. The image processing unit 108 transfers the generated preview image data to the console 3 under the control of the communication control unit 114 . The generated preview image is thereby displayed on the display unit 4 connected to the console 3 . By performing the offset correction using the already acquired offset image, the time until the preview image is displayed can be shortened.

Here, the offset image stored in the offset image memory 113 may be an image reduced for the preview image. However, if there are multiple processing patterns to be scaled down for the preview image, multiple offset images need to be stored. Therefore, when the number of processing patterns to be reduced for the preview image is large, the offset image corresponding to the signals output from all the pixels PIX is stored in the offset image memory 113, and the offset image for preview is stored according to the processing pattern. Generating an image can reduce the memory size of the offset image memory 113 .

After that, the image data subjected to offset correction by the offset correction unit 110 using the offset image acquired after the radiation image is captured is transferred to the console 3 under the control of the communication control unit 114 . A radiographic image based on the transferred image data is displayed as a main image on the display unit 4 connected to the console 3 .

A communication control unit 301 of the console 3 controls data transmission/reception with the radiation imaging apparatus 1, and operates, for example, software incorporated in a computer or the like. Thereby, data transmission/reception with the imaging control unit 102 is controlled, and imaging parameters such as an imaging region and imaging conditions are set. Here, the processing unit 303 of the console 3 can function as a processor that performs image processing (signal processing) for making the image data received from the radiation imaging apparatus 1 into a form suitable for diagnosis. Also, the storage unit 302 of the console 3 stores the image data received from the radiation imaging apparatus 1 . The display unit 4 displays a radiographic image based on the signal read from the radiation detection unit 2 and an operation UI based on the image data transmitted to the console 3 .

3 and 4 are flow charts and timing charts during imaging by the radiation imaging apparatus 1 and the radiation imaging system SYS in this embodiment. The operation of the radiation imaging apparatus 1 will be described with reference to FIGS. 3 and 4. FIG.

When the radiation imaging apparatus 1 is activated and enters an imaging standby state, the driving circuit 103 periodically performs a reset operation as the reset scanning control 105 to prevent dark charges from accumulating in the plurality of pixels PIX forming the radiation detection unit 2. (Fig. 4: TC401, Fig. 3: S001). The reset operation is performed in order from the first row (first row) to the last row (Y-th row) of the pixels PIX of the pixel unit 212, and returns to the first row when the last row is reached. Next, in S002 shown in FIG. 3, the detection unit 101 determines whether or not the radiation generation unit 500 has started to emit radiation. In other words, while the detection unit 101 detects the presence or absence of radiation irradiation, the drive circuit 103 controls the drive circuit 214 to sequentially reset the plurality of pixels PIX via the plurality of drive lines Vg. When the detection unit 101 does not detect the start of radiation irradiation, the reset operation is repeatedly executed (Fig. 4: TC401, Fig. 3: S001).

When the radiation generation unit 500 starts to emit radiation by an operation such as pressing an exposure switch by the user, the detection unit 101 detects the irradiation of radiation. When the detection unit 101 detects the start of radiation irradiation, the drive circuit 103 stops the reset scanning control 105 and stops the reset operation ( FIG. 4 : TC402, FIG. 3 : S003). Next, the drive circuit 103 shifts to the readout scan control 106, puts the switching elements T of all the pixels PIX in the pixel section 212 into a non-conducting state, and puts all the pixels PIX into a state of accumulating charges (Fig. 4: TC403 , FIG. 3: S004). By stopping the reset operation, each pixel PIX is brought into a state in which charges corresponding to irradiation of radiation are accumulated.

At this time, the drive circuit 103 stores information of the pixel unit 212 when the reset operation is stopped in the irradiation detection time information storage unit 104 as additional information. The incidental information includes information on the drive line Vg that supplies a signal for resetting the plurality of pixels PIX when the detection unit 101 detects irradiation of radiation, Information on the pixel group to which the pixel PIX that was performing the reset operation among the plurality of pixels PIX belongs, the signal value when the detection unit 101 detects radiation irradiation, and each group of the pixel groups of the plurality of pixels PIX at least one of the information on the arrangement of This supplementary information is information related to image display of the preview image and the main image displayed on the display unit 4 after the preview image.

Next, in S005, the detection unit 101 determines whether or not radiation irradiation has ended. If the irradiation of radiation has not ended, the operation of accumulating charges in the pixel PIX (FIG. 4: TC403, FIG. 3: S004) is continued. When the detection unit 101 detects the end of radiation irradiation, the drive circuit 103 performs readout control to sequentially scan each row of the pixel unit 212 in the readout scanning control 106, and outputs image signals from the pixels PIX of the pixel unit 212. Acquire (Fig. 4: TC404, Fig. 3: S006). Here, the image signal of the acquired radiographic image may be stored in the captured image memory 112 .

In the image signal for displaying the radiographic image output from the pixel PIX, due to the detection delay from the start of the actual radiation irradiation until the detection unit 101 detects the start of irradiation, the image signal of some rows Signal degradation can occur. More specifically, the pixel PIX, which was in reset operation when irradiation of radiation was detected, changes the amount of charge accumulated according to the irradiation of radiation to the amount of actually incident radiation by performing the reset operation. may become less than In displaying the preview image, in order to suppress the influence of deterioration of the image signal, the preview image generation unit 109 of the image processing unit 108 stores the reset operation stored in the irradiation detection time information storage unit 104. Information of the pixel unit 212 is acquired. Thereby, the preview image generation unit 109 of the image processing unit 108 identifies the signal from the pixel PIX that is highly likely to have a signal defect among the image signals.

The radiation irradiation end timing may be detected by the detection unit 101, or the imaging control unit 102 may wait for a specific fixed time to determine the end of irradiation and start the reading operation. Further, when the detection unit 101 detects the end of irradiation of radiation, for example, the pixel row that was performing the reset operation when the start of irradiation of radiation was detected does not turn off the switch element T, but turns it on. Monitoring of the amount of current flowing through the bias line Bs may be continued. This operation enables the detection unit 101 to detect the end of radiation irradiation.

Next, the preview image generation unit 109 of the image processing unit 108 determines an image signal to be used for generating preview image data. In this embodiment, two adjacent pixels PIX in the same row belonging to different pixel groups and connected to different drive lines Vg share the column signal line Sig. Therefore, when the reset operation is performed at the driving timing shown in FIG. The operation and resetting of pixels PIX at (odd, even) or (even, odd) coordinates as shown in FIG. 7(b) can be done row by row. By repeating the reset operation of the pixels PIX shown in FIGS. 7A and 7B for each row, all the pixels PIX can be scanned.

At this time, consider a case where the start of radiation irradiation is detected by the reset operation of the pixel PIX at the coordinates shown in FIG. 7(a). In this case, the image signals output from the pixels PIX at the coordinates shown in FIG. Since there is no signal, the possibility of signal degradation is low. Therefore, the preview image generation unit 109 of the image processing unit 108 generates preview image data from the image signal output from the pixel PIX shown in FIG. 7B (FIG. 3: S007). Next, the communication control unit 114 transfers the preview image data generated by the preview image generation unit 109 to the console 3 prior to the main image data for diagnosis (FIG. 4: TC405, FIG. 3: S007). . The preview image data transferred to the console 3 suppresses deterioration of the signal when the start of radiation irradiation is detected. is possible (Fig. 4: TC406, Fig. 3: S008).

In this way, after the irradiation of radiation is completed, the image processing unit 108 outputs from a pixel group that does not include the pixel PIX that was performing the reset operation when the detection unit 101 detected the irradiation of radiation among the plurality of pixels PIX. Preview image data is generated from the received image signal. As a result, preview image data can be generated at high speed without performing correction processing due to the reset operation at the start of radiation irradiation. In other words, it is possible to display a preview image on the display unit 4 within a short time after taking a radiographic image, and it is possible to realize a user-friendly radiographic apparatus 1 and radiographic system SYS.

Here, when the preview image data is generated by the preview image generation unit 109 of the image processing unit 108, the data other than the selected pixels in the partial reset operation at the time of irradiation detection is further thinned out to generate the preview image data. You may The preview image generating unit 109 of the image processing unit 108 reduces the captured image by thinning out the pixels PIX using the signal as shown in FIG. A reduced preview image can be generated and then transferred to the console 3 . In FIG. 8A, for example, hatched pixels PIX are used for generating (sampling) reduced preview image data, and white pixels PIX are thinned out.

As shown in FIG. 8A, image signals for preview image data are sampled from physically continuous pixels PIX. This makes it possible to reduce the influence of specific frequency noise, such as periodic signals (grid fringes) corresponding to the arrangement of the grid for removing scattered radiation from the subject, by thinning. The method of sampling the image signal of the reduced preview image data by the preview image generation unit 109 of the image processing unit 108 is not limited to the example shown in FIG. 8A, and other thinning methods can be used. . For example, interpolation processing may be used to generate a reduced preview image between pixels used to generate reduced preview image data. It is also possible to generate a reduced preview image by combining pixel values of pixels used for generating the reduced preview image and interpolation processing. The thinning ratio is not limited to the one illustrated in FIG. 8A, and various ratios can be set.

On the other hand, consider a case where the start of radiation irradiation is determined by the reset operation of the pixel group to which the pixel PIX selected in FIG. 7B belongs. In this case, the pixels PIX shown in FIG. 7A, rather than the pixel group to which the pixels PIX shown in FIG. , it is highly probable that no signal degradation has occurred. At this time, when the image signals of the pixels PIX hatched in FIG. 8(a) are used to generate reduced preview image data, the hatched pixels are all the pixels PIX shown in FIG. 7(b). Therefore, it includes pixels PIX in which image signals are degraded. Therefore, when the start of radiation irradiation is detected by the reset operation of the pixel PIX shown in FIG. The signal is used to generate data for the preview image. The preview image data generated by the preview image generation unit 109 of the image processing unit 108 is transferred to the console 3 prior to the main image data for diagnosis, and the preview image is displayed on the display unit 4 . When generating the thinned down image data, the preview image generation unit 109 thins out the pixels PIX using the image signal used when generating the preview image data, for example, as shown in FIG. It is possible to generate reduced preview image data in which the amount of data is reduced and then transfer it to the console 3 . The preview image data transferred to the console 3 is suppressed from signal deterioration caused by the reset operation when the start of radiation irradiation is detected. Immediate display is possible. At this time, the preview image data to be transferred to the console 3 includes, as supplementary information, information indicating that it is preview image data, and reset operation of a plurality of pixels PIX when the detection unit 101 detects irradiation of radiation. information on the drive line Vg that supplied a signal for the detection of radiation, information on the pixel group to which the pixel PIX that was performing the reset operation among the plurality of pixels PIX when the detection unit 101 detected radiation irradiation belongs, the plurality of pixels Information necessary for preview image display, such as information on the arrangement of each group of pixel groups of PIX, and information on whether or not to thin out pixels PIX that output image signals used for generating preview image data among a plurality of pixels PIX. Information may be included. This supplementary information indicates whether the image signal transferred for the preview image is, for example, the image signal output from the pixel PIX shown in FIG. can include identification information for identifying whether it is an image signal output from. That is, the identification information can be information of the pixel PIX that has output the image signal used for generating the preview image data among the plurality of pixels PIX. Details of this identification information will be described later.

After completion of the readout operation of the image signals used for the radiographic image ( FIG. 3 : S006), the drive circuit 103 controls the drive circuit 214 as the readout scan control 106 to turn off the switch elements T of all the pixels PIX again. state, and the conversion element S is brought into the charge accumulation state (Fig. 4: TC407, Fig. 3: S009). This processing includes the above-described preview image data generation, preview image data transfer processing (Fig. 4: TC405, Fig. 3: S007), and preview image data display processing (Fig. 4: TC406, Fig. 3: S008) may be executed in parallel. By performing parallel processing, it is possible to shorten the time from generation of preview image data and display of the preview image to generation of main image data for diagnosis and display of the main image.

Next, in S010 of FIG. 3, the drive circuit 103 determines whether or not the same standby time as the accumulation time (TC403 in FIG. 4, S004 in FIG. 3) has elapsed in the readout scanning control 106. do. If the standby time has not elapsed, the operation of accumulating charges in the conversion element S is continued (Fig. 4: TC407, Fig. 3: S009). This continues the accumulation of dark charge. When the drive circuit 103 determines that the time equal to the accumulation time during radiation irradiation has passed, the readout scanning control 106 performs the readout operation of the signals of the offset image from each pixel PIX to obtain the offset image of only the dark charge component. (Fig. 4: TC408, Fig. 3: S011). Next, the offset correction unit 110 of the image processing unit 108 offset-corrects the signals output from all the pixels PIX of the image signals of the radiographic image stored in the captured image memory 112 using the acquired offset image. (Fig. 3: S012). The offset correction unit 110 acquires main image data from which dark charge components are removed by offset correction that subtracts offset image data components from radiographic image data. The communication control unit 114 transfers the main image data offset-corrected by the offset correction unit 110 to the console 3 (TC409, S013).

Unlike the preview image, in the main image, degradation may occur in the signal output from the pixel row near the pixel PIX that was performing the reset operation when the start of radiation irradiation was detected. Therefore, it is necessary to correct the signal of the main image data. Therefore, the drive circuit 103 reads the additional information of the pixel unit 212 when the reset operation is stopped from the irradiation detection time information storage unit 104, and stores this information in the main image data generated by the offset correction unit 110 of the image processing unit 108. Attach supplementary information. The communication control unit 114 transfers the incidental information to the console 3 . The processing unit 303 of the console 3 acquires the information of the drive line Vg that supplies a signal for resetting the plurality of pixels PIX when the detection unit 101 detects radiation irradiation among the incidental information and the detection unit 101. A pixel PIX whose signal is assumed to be degraded may be specified from the information of the pixel group to which the pixel PIX that was performing the reset operation among the plurality of pixels PIX when the radiation irradiation was detected belongs. Further, for example, the processing unit 303 of the console 3 detects signal deterioration from the signal value when the detection unit 101 detects irradiation of radiation and information on the arrangement of each group of pixel groups of the plurality of pixels PIX. It is also possible to identify pixels PIX assumed to be , peripheral pixels PIX, information on their output values, and the like. Using the specified information, the processing unit 303 performs signal processing such as correction of the signal value of the received main image data and correction for interpolating the loss of the signal value. Image processing is performed (Fig. 4: TC410, Fig. 3: S014). The display unit 4 displays an image based on the main image data subjected to image processing by the processing unit 303 (Fig. 4: TC411, Fig. 3: S015).

The timing of transferring the incidental information read from the irradiation detection time information storage unit 104 to the console 3 may be before or after the main image data. Alternatively, supplementary information may be transferred in addition to the main image data. This image data may be transferred at any timing as long as accompanying information related to pixels that were reset when the detection unit 101 detected radiation irradiation is associated with the main image data.

In this embodiment, the processing unit 303 of the console 3 performs the correction processing of the main image data based on the supplementary information, but the present invention is not limited to this. For example, the image processing unit 108 of the radiation imaging apparatus 1 may perform correction processing of the main image data based on the supplementary information. In this case, there is no need to transfer the incidental information to the console 3, and the image processing unit 108 may use this information to perform correction processing.

In this embodiment, two adjacent pixels arranged in the same row belonging to different pixel groups connected to different drive lines Vg are connected to a common column signal line Sig. This makes it possible to suppress the circuit scale of the readout circuit 107 . Furthermore, preview image data is generated from image signals output from pixel groups that do not include the pixels PIX that were reset when the detection unit 101 detected radiation irradiation among the plurality of pixels PIX. . At this time, the selection pattern of the pixels PIX used to generate the preview image data is switched for each frame in which the reset operation is performed, according to the arrangement of the pixels PIX in the pixel group. As a result, while suppressing the circuit scale required for the radiation imaging apparatus 1, it is possible to suppress the need to correct the signal output from the pixel PIX when the start of radiation irradiation is detected, and to display the processing preview image. Delay can be reduced.

Pixels PIX (pixel groups) shown in FIGS. 7A and 7B are adjacent to each other in the row direction among the plurality of pixels PIX, and are connected to the same column signal line Sig among the plurality of column signal lines Sig. belong to different pixel groups. Pixels PIX that are adjacent to each other in the column direction among the plurality of pixels PIX belong to different pixel groups. In the examples shown in FIGS. 7A and 7B, two pixel groups are arranged, and pixels PIX belonging to one pixel group out of the plurality of pixels PIX and a plurality of pixels PIX belonging to one pixel group are arranged in the row direction. Among the pixels PIX, the pixels PIX belonging to the other pixel group are alternately arranged, and in the column direction, the pixels PIX belonging to one pixel group among the plurality of pixels PIX and the other pixel group among the plurality of pixels PIX. , are alternately arranged.

However, it is not limited to this. Pixels PIX (pixel groups) may be arranged as shown in FIGS. That is, pixels PIX adjacent to each other in the column direction among the plurality of pixels PIX may belong to the same pixel group. In the example shown in FIGS. 9A and 9B, two pixel groups are arranged, and pixels PIX belonging to one pixel group among the plurality of pixels PIX and the plurality of pixels PIX belonging to one pixel group are arranged in the row direction. and pixels PIX belonging to the other pixel group are alternately arranged, and pixels PIX belonging to one pixel group out of the plurality of pixels PIX or pixels belonging to the other pixel group out of the plurality of pixels PIX are arranged in the column direction. PIX are arranged continuously. Even in this case, two adjacent pixels PIX in the same row belonging to different pixel groups and connected to different drive lines Vg are connected to a common column signal line Sig. An operation similar to that of the device 1 can be realized.

In the reset operation (TC401, S001) of FIGS. 3 and 4, for example, consider a case where the start of radiation irradiation is detected by the reset drive of any pixel PIX shown in FIG. 9A. In this case, a pixel group that does not include the pixel PIX that was in the reset operation when the start of radiation irradiation was detected, that is, the image signal output from the pixel PIX shown in FIG. , the image processing unit 108 may generate preview image data. Similarly, consider the case where the start of radiation irradiation is detected by reset driving of any of the pixels PIX shown in FIG. 9B. In this case, a pixel group that does not include the pixel PIX that was in the reset operation when the start of radiation irradiation was detected, that is, the image signal output from the pixel PIX shown in FIG. , the image processing unit 108 may generate preview image data.

In the present embodiment, it has been described that the pixels PIX arranged in the pixel unit 212 are divided into two pixel groups, and the pixels PIX for acquiring the image signals are selected when preview image data is generated. However, it is not limited to this. The pixels PIX arranged in the pixel unit 212 of the radiation detection unit 2 may be divided into three or more pixel groups. For example, consider a case where the pixels PIX are divided into three pixel groups and the start of radiation irradiation is detected by the reset operation of the pixels PIX belonging to the first pixel group. In this case, the image processing unit 108 may generate preview image data using image signals output from the pixels PIX belonging to the second pixel group and the third pixel group. In this case, the image processing unit 108 may generate preview image data using image signals output from pixels PIX belonging to either the second pixel group or the third pixel group. In the latter case, the amount of preview image data is reduced, so the delay until the preview image is displayed on the display unit 4 can be shortened. The grouping of the pixels PIX and the number of pixels PIX used for the preview image may be appropriately determined according to the specifications required for the radiation imaging apparatus 1 and the radiation imaging system SYS.

As described above, in the radiation imaging apparatus 1, it is possible to immediately obtain a good preview image while suppressing the circuit scale of the readout circuit 107. FIG. In other words, it is possible to realize the radiation imaging apparatus 1 and the radiation imaging system SYS that are easy to use and that reduce the user's stress during operation.

By the way, Patent Document 1 discloses that a plurality of pixels are divided into a plurality of groups, and when reset scanning for one group ends, reset scanning for the next group is started. If the group of pixels for which reset scanning is performed changes during the period from the actual start of radiation irradiation to the detection of radiation irradiation, the image quality of the preview image may be affected. The operation of the radiation imaging apparatus 1 for suppressing this influence will be described below.

3 and 10 are flow charts and timing charts of the radiation imaging apparatus 1 and the radiation imaging system SYS in this embodiment when imaging. The operation of the radiation imaging apparatus 1 will be described with reference to FIGS. 3 and 10. FIG. Since the configurations of the radiation imaging apparatus 1 and the radiation imaging system SYS may be the same as those described above, description thereof is omitted here.

When the radiation imaging apparatus 1 is activated and enters an imaging standby state, the driving circuit 103 periodically performs a reset operation as the reset scanning control 105 to prevent dark charges from accumulating in the plurality of pixels PIX forming the radiation detection unit 2. (Fig. 10: TC1001, Fig. 3: S001). The reset operation is sequentially performed for each pixel group from the top row (first row) side of the pixels PIX of the pixel section 212 toward the last row (Yth row) side. When the last row of one pixel group is reached, the reset operation is started from the first row of the next pixel group. Next, in S002 shown in FIG. 3, the detection unit 101 determines whether or not the radiation generation unit 500 has started to emit radiation. In other words, while the detection unit 101 detects the presence or absence of irradiation of radiation, the drive circuit 103 controls the drive circuit 214 to reset the plurality of pixels PIX sequentially for each pixel group through the plurality of drive lines Vg. Let When the detection unit 101 does not detect the start of radiation irradiation, the reset operation is repeatedly executed (FIG. 10: TC1001, FIG. 3: S001).

When the radiation generation unit 500 starts to emit radiation by an operation such as pressing an exposure switch by the user, the detection unit 101 detects the irradiation of radiation. When the detection unit 101 detects the start of radiation irradiation, the driving circuit 103 stops the reset scanning control 105 to stop the reset operation (TC1002 in FIG. 10, S003 in FIG. 3). Next, the driving circuit 103 shifts to the readout scanning control 106, puts the switch elements T of all the pixels PIX in the pixel section 212 into a non-conducting state, and puts all the pixels PIX into a state of accumulating charges (FIG. 10: TC1003 , FIG. 3: S004). By stopping the reset operation, each pixel PIX is brought into a state in which charges corresponding to irradiation of radiation are accumulated.

At this time, the drive circuit 103 stores information of the pixel unit 212 when the reset operation is stopped in the irradiation detection time information storage unit 104 as additional information. The incidental information includes information on the drive line Vg that supplies a signal for resetting the plurality of pixels PIX when the detection unit 101 detects irradiation of radiation, Information on the pixel group to which the pixel PIX that was performing the reset operation among the plurality of pixels PIX belongs, the signal value when the detection unit 101 detects radiation irradiation, and each group of the pixel groups of the plurality of pixels PIX at least one of the information on the arrangement of As will be described later, this incidental information is information related to image display of the main image displayed on the display unit 4 after the preview image.

Next, in S005 shown in FIG. 3, the detection unit 101 determines whether or not radiation irradiation has ended. If the irradiation of radiation has not ended, the operation of accumulating charges in the pixel PIX (FIG. 10: TC1003, FIG. 3: S004) is continued. When the detection unit 101 detects the end of radiation irradiation, the drive circuit 103 performs readout control to sequentially scan each row of the pixel unit 212 in the readout scanning control 106, and outputs image signals from the pixels PIX of the pixel unit 212. Acquire (Fig. 10: TC1004, Fig. 3: S006). Here, the image signal of the acquired radiographic image may be stored in the captured image memory 112 .

The radiation irradiation end timing may be detected by the detection unit 101, or the imaging control unit 102 may wait for a specific fixed time to determine the end of irradiation and start the reading operation. Further, when the detection unit 101 detects the end of irradiation of radiation, for example, the pixel row that was performing the reset operation when the start of irradiation of radiation was detected does not turn off the switch element T, but turns it on. Monitoring of the amount of current flowing through the bias line Bs may be continued. This operation enables the detection unit 101 to detect the end of radiation irradiation.

Next, the preview image generation unit 109 of the image processing unit 108 determines an image signal to be used for generating preview image data. In this embodiment, two adjacent pixels PIX in the same row belonging to different pixel groups and connected to different drive lines Vg share the column signal line Sig. Therefore, when the reset operation is performed at the driving timing shown in FIG. The reset operation of the pixel group to which the pixel PIX belongs, and the reset operation of the pixel group to which the pixel PIX at the coordinates (odd row, even column) or (even row, odd column) belongs, as shown in FIG. can be performed alternately. By sequentially performing the reset operation of the pixels PIX shown in FIGS. 11A and 11B for each pixel group, all the pixels PIX can be scanned.

In the image signal for displaying the radiographic image output from the pixel PIX, due to the detection delay from the start of the actual radiation irradiation until the detection unit 101 detects the start of the irradiation, the image signal for some rows is reduced. Signal degradation can occur. More specifically, the pixels PIX that have been reset in the period from the start of irradiation until the detection unit 101 detects the irradiation of radiation are reset in accordance with the irradiation of radiation by performing the reset operation. The amount of charge applied may be less than the amount of radiation actually incident.

Here, as shown in FIG. 10, consider a case where the period from the start of radiation irradiation to the detection of radiation by the detection unit 101 straddles reset operations between different pixel groups. In the operation described in Patent Document 1, among the plurality of pixels PIX, the pixels PIX of the pixel groups other than the pixel group including the reset pixel that was performing the reset operation when the detection unit 101 detected the irradiation of the radiation are output. The signal is used to generate data for a preview image. However, in the case shown in FIG. 10, the pixel group that was resetting when radiation irradiation was detected is the pixel group that includes the pixel PIX connected to the drive line Vg (Ys−1). Therefore, the preview image data is generated using the image signal output from the pixel group including the pixel PIX connected to the drive line Vg(Y-2). However, as shown in FIG. 10, the pixel PIX connected to the drive line Vg(Y-2) is reset after being irradiated with radiation. That is, when the preview image data is generated using the image signal output from the pixel group including the pixel PIX connected to the drive line Vg(Y-2), the image data connected to the drive line Vg(Y-2) is generated. There is a possibility that the image quality of the preview image displayed on the display unit 4 may be degraded due to the deterioration of the image signal of the pixel PIX.

Therefore, in the present embodiment, in order to suppress the influence of such image signal deterioration, the preview image generation unit 109 of the image processing unit 108 stops the reset operation stored in the irradiation detection time information storage unit 104. The information of the pixel portion 212 at that time is acquired. Here, it is assumed that the detection unit 101 detects the start of radiation irradiation when the pixels PIX in the fifth row shown in FIG. 11A are reset. First, as shown in FIG. is detected to be exposed to radiation. In this case, with the 5th row as a boundary, it is unlikely that the reset operation was performed from the 1st row to the 5th row from the start of radiation irradiation to the detection of radiation irradiation. ), the preview image data is generated using the image signal output from the pixel PIX of the pixel group to which the pixel PIX at the coordinates (odd row, even column) or (even row, odd column) belongs. After the fifth row where the detection unit 101 detects irradiation of radiation, the sixth row to the last row are shown in FIG. The preview image data is generated using the image signal output from the pixel PIX of the pixel group to which the pixel PIX at the coordinates (odd row, odd column) or (even row, even column) belongs. That is, when irradiation of radiation is detected during the reset operation of the pixel group to which the pixel PIX shown in FIG. Using the signal, the preview image generation unit 109 of the image processing unit 108 generates preview image data ( FIG. 3 : S007).

Similarly, when the pixel group to which the pixel PIX at the coordinates (odd row, even column) or (even row, odd column) shown in FIG. Let us consider the case of detecting the irradiation of . In this case, from the 1st row to the 5th row with the 5th row as a boundary, it is unlikely that the reset operation was performed from the start of radiation irradiation to the detection of irradiation. ) of (odd row, odd column) or (even row, even column) of the pixel group to which the pixel PIX belongs. After the fifth row where the detection unit 101 detects irradiation of radiation, the sixth row to the last row are shown in FIG. The preview image data is generated using the image signal output from the pixel PIX of the pixel group to which the pixel PIX at the coordinates (odd row, even column) or (even row, odd column) belongs. That is, when irradiation of radiation is detected during the reset operation of the pixel group to which the pixel PIX shown in FIG. Using the signal, the preview image generation unit 109 of the image processing unit 108 generates preview image data ( FIG. 3 : S007).

Next, the communication control unit 114 transfers the preview image data generated by the preview image generation unit 109 to the console 3 prior to the main image data for diagnosis (FIG. 10: TC1005, FIG. 3: S007). . In the preview image data transferred to the console 3, deterioration of the image signal due to the reset operation from the start of radiation irradiation to the detection of irradiation is suppressed, so the need for image correction processing is low. It can be displayed immediately on the display unit 4 (FIG. 10: TC1006, FIG. 3: S008).

In this way, after the radiation irradiation is completed, the preview image generation unit 109 of the image processing unit 108 resets the reset pixels ( For example, the row in which the pixels PIX in the fifth row of FIG. 11A (the same example is shown below) is arranged is set as the reset row (fifth row). As described above, the preview image generation unit 109 of the image processing unit 108 acquires the information of the reset row as the information of the pixel unit 212 when the reset operation is stopped, which is stored in the irradiation detection time information storage unit 104. is possible. Next, the preview image generation unit 109 of the image processing unit 108 generates the reset row signal among the first image signals output from the pixel group including the reset pixel (the pixel group to which the pixel PIX shown in FIG. 11A belongs). image signals output from at least one row of pixels PIX arranged between the next row to the last row of the pixel PIX, and a pixel group not including reset pixels (pixels shown in FIG. 11(b) preview image data by using the image signals output from the pixels PIX arranged between the first row and the reset row among the second image signals output from the pixel group to which the PIX belongs. Generate. As a result, it is possible to generate preview image data at high speed without performing correction processing due to the reset operation from the start of radiation irradiation to the detection of radiation irradiation. In other words, it is possible to display a preview image on the display unit 4 in a short time after the radiographic image is captured, and it is possible to realize the user-friendly radiographic apparatus 1 and the radiographic system SYS.

Here, when the preview image data is generated by the preview image generating unit 109 of the image processing unit 108, the image signal of the pixel PIX selected as described above is further thinned out to generate the preview image data. may When the preview image generation unit 109 of the image processing unit 108 generates thinned-down image data, for example, as shown in FIG. , a reduced preview image obtained by reducing the captured image can be generated and transferred to the console 3 . In FIG. 12, for example, hatched pixels PIX are used for generation (sampling) of reduced preview image data, and white pixels PIX are thinned out.

The method of sampling the image signal of the reduced preview image data by the preview image generation unit 109 of the image processing unit 108 is not limited to the example shown in FIG. 12, and other thinning methods can be used. For example, interpolation processing may be used to generate a reduced preview image between pixels used to generate reduced preview image data. It is also possible to generate a reduced preview image by combining pixel values of pixels used for generating the reduced preview image and interpolation processing. The thinning ratio is not limited to the one illustrated in FIG. 12, and various ratios can be set.

Further, in the above description, among the second image signals output from pixel groups that do not include reset pixels, the image signals output from the pixels PIX arranged between the first row and the reset row are used as the preview image data. explained that it is used to generate However, among the second image signals output from pixel groups that do not include reset pixels, some of the image signals output from the pixels PIX arranged on the final row side of the reset row are used for the preview image. May be used to generate data. Of the pixels PIX belonging to a pixel group that does not include reset pixels, the pixels PIX that are arranged close to the reset row may have undergone a reset operation between the start of actual radiation irradiation and the detection of radiation irradiation. low. For this reason, for example, among the second image signals output from pixel groups that do not include reset pixels, from the first row to the last row with respect to the reset row, the fifth row, the tenth row, and further, for example, the 20th row. The image signals output from the pixels PIX arranged between the rows may be used to generate the preview image data. Further, for example, 1% of the number of rows arranged in the pixel section 212 on the side of the last row with respect to the reset row from the first row among the second image signals output from the pixel groups that do not include the reset pixels, Image signals output from the pixels PIX arranged between rows 2%, 5%, and further, for example, 10% ahead may be used to generate preview image data. In these cases, the preview image generating unit 109 of the image processing unit 108 generates the preview image data by selecting the first image signal output from the pixel group including the reset pixel and the pixel group not including the reset pixel. The image signals output from the pixels PIX arranged from the row next to the row where the pixels PIX used for generating the preview image data are arranged to the last row may be used.

In this way, the radiation imaging apparatus 1 generates a preview image so as not to use pixels PIX that are likely to have undergone a reset operation between the start of actual radiation irradiation and the detection of radiation irradiation. A plurality of selection patterns of pixels PIX used for generation are provided. The preview image generation unit 109 of the image processing unit 108 switches the selection pattern of pixels PIX used for generating preview image data based on the scanning line selected when the start of radiation irradiation is detected. This enables the radiation imaging apparatus 1 and the radiation imaging system SYS to display a preview image with good image quality on the display unit 4 with a short display delay. Also, as described above, the preview image data may include supplementary information.

After completion of the readout operation of the image signals used for the radiographic image ( FIG. 3 : S006), the drive circuit 103 controls the drive circuit 214 as the readout scan control 106 to turn off the switch elements T of all the pixels PIX again. state to bring the conversion element S into a charge accumulation state (FIG. 10: TC1007, FIG. 3: S009). This processing includes the above-described preview image data generation, preview image data transfer processing (Fig. 10: TC1005, Fig. 3: S007), and preview image data display processing (Fig. 10: TC1006, Fig. 3: S008) may be executed in parallel. By performing parallel processing, it is possible to shorten the time from generation of preview image data and display of the preview image to generation of main image data for diagnosis and display of the main image.

Next, in S010 of FIG. 3, the drive circuit 103 determines whether or not the same standby time as the accumulation time (TC1003 in FIG. 10, S004 in FIG. 3) has passed in the readout scanning control 106. do. If the standby time has not elapsed, the operation of accumulating charges in the conversion element S is continued (FIG. 10: TC1007, FIG. 3: S009). This continues the accumulation of dark charge. When the drive circuit 103 determines that the time equal to the accumulation time during radiation irradiation has passed, the readout scanning control 106 performs the readout operation of the signals of the offset image from each pixel PIX to obtain the offset image of only the dark charge component. (Fig. 10: TC1008, Fig. 3: S011). Next, the offset correction unit 110 of the image processing unit 108 offset-corrects the signals output from all the pixels PIX of the image signals of the radiographic image stored in the captured image memory 112 using the acquired offset image. (Fig. 3: S012). The offset correction unit 110 acquires main image data from which dark charge components are removed by offset correction that subtracts offset image data components from radiographic image data. The communication control unit 114 transfers the main image data subjected to the offset correction by the offset correction unit 110 to the console 3 (FIG. 10: TC1009, FIG. 3: S013).

Unlike the preview image, in the main image, degradation may occur in the signal output from the pixel row near the pixel PIX that was performing the reset operation when the start of radiation irradiation was detected. Therefore, it is necessary to correct the signal of the main image data. Therefore, the drive circuit 103 reads the additional information of the pixel unit 212 when the reset operation is stopped from the irradiation detection time information storage unit 104, and stores this information in the main image data generated by the offset correction unit 110 of the image processing unit 108. Attach supplementary information. The communication control unit 114 transfers the incidental information to the console 3 . The processing unit 303 of the console 3 acquires the information of the drive line Vg that supplies a signal for resetting the plurality of pixels PIX when the detection unit 101 detects radiation irradiation among the incidental information and the detection unit 101. A pixel PIX whose signal is assumed to be degraded may be specified from the information of the pixel group to which the pixel PIX that was performing the reset operation among the plurality of pixels PIX when the radiation irradiation was detected belongs. Further, for example, the processing unit 303 of the console 3 detects signal deterioration from the signal value when the detection unit 101 detects irradiation of radiation and information on the arrangement of each group of pixel groups of the plurality of pixels PIX. It is also possible to identify pixels PIX assumed to be , peripheral pixels PIX, information on their output values, and the like. Using the specified information, the processing unit 303 performs signal processing such as correction of the signal value of the received main image data and correction for interpolating the loss of the signal value. Image processing is performed (Fig. 10: TC1010, Fig. 3: S014). The display unit 4 displays an image based on the main image data subjected to image processing by the processing unit 303 (FIG. 10: TC1011, FIG. 3: S015).

The timing of transferring the incidental information read from the irradiation detection time information storage unit 104 to the console 3 may be before or after the main image data. Alternatively, supplementary information may be transferred in addition to the main image data. This image data may be transferred at any timing as long as accompanying information related to pixels that were in reset operation when the detection unit 101 detected irradiation of radiation is associated with the main image data.

In this embodiment, the processing unit 303 of the console 3 performs the correction processing of the main image data based on the supplementary information, but the present invention is not limited to this. For example, the image processing unit 108 of the radiation imaging apparatus 1 may perform correction processing of the main image data based on the supplementary information. In this case, there is no need to transfer the incidental information to the console 3, and the image processing unit 108 may use this information to perform correction processing.

The radiation imaging apparatus 1 according to the present embodiment uses the information of the pixels PIX (pixel rows) that have been reset when the start of radiation irradiation is detected. As a result, even when the reset operation straddles different pixel groups from the start of radiation irradiation to the detection of irradiation by the detection unit 101, processing for correcting image deterioration caused by the reset operation is performed. A preview image can be displayed without As a result, the display delay until the preview image is displayed is reduced, and the user-friendly radiation imaging apparatus 1 and radiation imaging system SYS are realized. Further, as shown in FIG. 2, the radiation imaging apparatus 1 of the present embodiment shares the column signal line Sig with two pixel columns, thereby suppressing the circuit scale of the readout circuit 107 and reducing the apparatus cost. be able to.

Pixels PIX (pixel groups) shown in FIGS. 11A and 11B are adjacent to each other in the row direction among the plurality of pixels PIX, and are connected to the same column signal line Sig among the plurality of column signal lines Sig. belong to different pixel groups. Pixels PIX that are adjacent to each other in the column direction among the plurality of pixels PIX belong to different pixel groups. In the example shown in FIGS. 11A and 11B, two pixel groups are arranged, and pixels PIX belonging to one pixel group out of the plurality of pixels PIX and a plurality of pixels PIX belonging to one pixel group are arranged in the row direction. Among the pixels PIX, the pixels PIX belonging to the other pixel group are alternately arranged, and in the column direction, the pixels PIX belonging to one pixel group among the plurality of pixels PIX and the other pixel group among the plurality of pixels PIX. , are alternately arranged.

However, it is not limited to this. Pixels PIX (pixel groups) may be arranged as shown in FIGS. That is, pixels PIX that are adjacent to each other in the column direction among the plurality of pixels PIX may belong to the same pixel group. In the example shown in FIGS. 13A and 13B, two pixel groups are arranged, and pixels PIX belonging to one pixel group out of the plurality of pixels PIX and the plurality of pixels PIX belonging to one pixel group are arranged in the row direction. and pixels PIX belonging to the other pixel group are alternately arranged, and pixels PIX belonging to one pixel group out of the plurality of pixels PIX or pixels belonging to the other pixel group out of the plurality of pixels PIX are arranged in the column direction. PIX are arranged continuously. Even in this case, two adjacent pixels PIX in the same row belonging to different pixel groups and connected to different drive lines Vg are connected to a common column signal line Sig. An operation similar to that of the device 1 can be realized.

3 and 10 (FIG. 10: TC1001, FIG. 3: S001), for example, the reset operation of the pixel group to which the pixels PIX at the odd-numbered column coordinates belong as shown in FIG. 13(a) is performed. Consider a case where the detection unit 101 detects irradiation of radiation when the radiation is applied. In this case, the pixels PIX of even-numbered column coordinates shown in FIG. Preview image data is generated using image signals output from the pixels PIX of the pixel group. Further, after the fifth row where the detection unit 101 has detected radiation irradiation, from the sixth row to the last row, the pixels of the pixel group to which the pixel PIX at the odd-numbered column coordinates shown in FIG. 13A belong. Preview image data is generated using the image signal output from the PIX. That is, when irradiation of radiation is detected during the reset operation of the pixel group to which the pixel PIX shown in FIG. Using the signal, the preview image generation unit 109 of the image processing unit 108 generates preview image data ( FIG. 3 : S007).

Similarly, consider a case where the detection unit 101 detects irradiation of radiation during the reset operation of the pixel group to which the pixels PIX at the even-numbered column coordinates belong, as shown in FIG. 13B. In this case, pixels PIX of odd-numbered column coordinates shown in FIG. Preview image data is generated using image signals output from the pixels PIX of the pixel group. Further, after the fifth row where the detection unit 101 has detected radiation irradiation, from the sixth row to the last row, the pixels of the pixel group to which the pixel PIX at the coordinates of the even-numbered column shown in FIG. 13B belong. Preview image data is generated using the image signal output from the PIX. That is, when irradiation of radiation is detected during the reset operation of the pixel group to which the pixel PIX shown in FIG. Using the signal, the preview image generation unit 109 of the image processing unit 108 generates preview image data ( FIG. 3 : S007).

In the examples shown in FIGS. 13(a) to 13(d), the case where pixels PIX belong to different pixel groups in odd-numbered columns and even-numbered columns has been described. However, the present invention is not limited to this, and for example, the pixels PIX in odd-numbered rows and even-numbered rows may belong to different pixel groups. In this case, for example, consider a case where the detection unit 101 detects irradiation of radiation while performing a reset operation on a pixel group to which pixels PIX at odd-numbered row coordinates belong. In this case, the pixels of the pixel group to which the pixels PIX at the coordinates of the even-numbered rows belong from the first row to the fifth row, bordering on the row (for example, the fifth row) where radiation irradiation is detected in the reset operation. The preview image data is generated using the image signal output from the PIX (for example, the pixels PIX arranged in the second and fourth rows). In addition, after the fifth row where the detection unit 101 has detected radiation irradiation, from the sixth row to the last row, the pixels PIX of the pixel group to which the pixel PIX at the odd-numbered row coordinates belong (for example, the seventh row, The preview image data is generated using the image signals output from the pixels (PIX) arranged in the 9th row . . . . This makes it possible to display a preview image with good image quality on the display unit 4 while suppressing the display delay.

In the present embodiment, it has been described that the pixels PIX arranged in the pixel unit 212 are divided into two pixel groups, and the pixels PIX for acquiring the image signals are selected when preview image data is generated. However, it is not limited to this. The pixels PIX arranged in the pixel unit 212 of the radiation detection unit 2 may be divided into three or more pixel groups. For example, consider a case where the pixels PIX are divided into three pixel groups and the start of radiation irradiation is detected by the reset operation of the pixels PIX belonging to the first pixel group. In this case, the preview image generation unit 109 of the image processing unit 108 performs the preview using the image signals output from the pixels PIX belonging to the second pixel group and the third pixel group from the first row side to the reset row. Generate image data. At this time, preview image data may be generated using image signals output from pixels PIX belonging to either the second pixel group or the third pixel group. By reducing the number of image signals used for the preview image data, the amount of data is suppressed, and the delay until the preview image is displayed on the display unit 4 can be shortened. Also, the preview image generation unit 109 of the image processing unit 108 generates preview image data using the image signals output from the pixels PIX belonging to the first pixel group from the row next to the reset row to the last row. do. In this case, the pixels PIX belonging to the first pixel group, the pixels PIX belonging to the second pixel group, and the pixels PIX belonging to the third pixel group may be arranged in order in one row. Also, for example, the pixels PIX belonging to the first pixel group, the pixels PIX belonging to the second pixel group, and the pixels PIX belonging to the third pixel group may be arranged in order row by row in the column direction. The grouping of the pixels PIX and the number of pixels PIX used for the preview image may be appropriately determined according to the specifications required for the radiation imaging apparatus 1 and the radiation imaging system SYS.

As described above, in the radiation imaging apparatus 1, it is possible to suppress the deterioration of the image signal due to the reset operation from the start of radiation irradiation to the detection of radiation, and to immediately obtain a good preview image. Become. In other words, it is possible to realize the radiation imaging apparatus 1 and the radiation imaging system SYS that are easy to use and that reduce the user's stress during operation.

In each of the above-described embodiments, the image processing unit 108 of the radiation imaging apparatus 1 determines the pixels PIX using image signals for displaying a preview image based on the characteristics of the structure of the radiation detection unit 2 and the drive control method. explained the case of On the other hand, when designing the radiation imaging system SYS, the radiation imaging apparatus 1 and the console 3 may be designed separately. When the radiation imaging apparatus 1 and the console 3 are designed in parallel, or when the radiation imaging apparatus 1 is designed first, the radiation imaging apparatus 1 that is combined when the console 3 is designed displays a preview image. The data amount, data format, transfer method, etc. of the image signal may be taken into account in the design. However, if the console 3 is designed first, the amount of preview image data, the data format, the transfer method, and the like for displaying the preview image of the radiation imaging apparatus 1 are determined by the processing unit of the console 3. There may be a case where the processing of 303 is not suitable or a case where it cannot be handled in the first place.

For example, if the amount of preview image data transmitted from the radiation imaging apparatus 1 is different from the amount of data assumed in the communication control unit 301 or storage unit 302, the transferred preview image data may not be received correctly. have a nature. Further, if the respective signal data of the preview image data are not transferred in the expected order, the transferred data cannot be rearranged in the processing unit 303, and the preview image cannot be correctly displayed on the display unit 4. there is a possibility. Also, when the processing unit 303 performs correction processing for preview image data, there is a possibility that correction cannot be performed correctly.

In addition, when capturing images in a short cycle such as when capturing a moving image, or when capturing images of many people in a short time such as during a medical checkup, quick display of a preview image may be emphasized rather than image quality. On the other hand, depending on the imaging part, the image quality may be prioritized over the display time even in the preview image. Therefore, for example, the console 3 may transmit, to the radiation imaging apparatus 1, instruction information for instructing a method of generating preview image data according to an imaging region and an imaging technique before imaging a radiation image. . Here, the console 3 transmits instruction information to the radiation imaging apparatus 1, and the radiation imaging apparatus 1 determines pixels PIX for outputting image signals used for generating preview image data according to the instruction information. explain. Since the configurations of the radiation imaging apparatus 1 and the radiation imaging system SYS may be the same as those described above, description thereof is omitted here.

14, the console 3 transmits instruction information instructing a method of generating preview image data to the radiation imaging apparatus 1, and the radiation imaging apparatus 1 transmits an image signal used for generating preview image data in accordance with the instruction information. FIG. 10 is a flowchart showing an operation example of determining pixels PIX to be output; For example, the processing unit 303 of the console 3 not only performs image processing (signal processing) for converting image data received from the radiation imaging apparatus 1 into a form suitable for diagnosis, but also processes the radiation imaging apparatus 1 as described below. can function as a processor to control the operation of The flow diagram of FIG. 14 will be described below.

First, communication is started between the radiation imaging apparatus 1 and the console 3 (S1401). For example, when auto-negotiation is set between the radiation imaging apparatus 1 and the console 3, the communication speed is determined by a sequence such as FLP.

Next, the console 3 transmits an initial setting command to the radiation imaging apparatus 1 in preparation for initializing the radiation imaging apparatus 1 (S1402). For example, the console 3 transmits a command for acquiring parameters such as time setting, temperature information of the radiation imaging apparatus 1, and the state of charge of the battery. The radiation imaging apparatus 1 performs initialization according to the initialization command from the console 3 (S1403). When the initial setting is completed, the radiation imaging apparatus 1 responds to the console 3 with parameters such as the temperature information of the radiation imaging apparatus 1 and the state of charge of the battery, and notifies the completion of the initial setting.

When the initial setting of the radiation imaging apparatus 1 is completed, the user sets the imaging protocol using the console 3 (S1404). Since an imaging region, an imaging technique, and the like are set by setting the imaging protocol, various parameters in the radiation imaging apparatus 1 at the time of imaging are determined. The parameters at the time of imaging include an imaging mode, presence or absence of various image processing, the number of images to be captured, an imaging ID, and the like. Further, instruction information for determining pixels PIX for outputting image signals used for generating preview image data is also included in the imaging parameters. The instruction information can include information on the number of pixels PIX that output image signals used for generating preview image data, information on the positions, and the like. For example, according to the instruction information, the image signals output from the pixels PIX shown in FIG. 8A and the pixels PIX shown in FIG. The use is determined in the radiation imaging apparatus 1 . For example, the console 3 can transfer one piece of instruction information out of a plurality of types of instruction information to the radiation imaging apparatus 1 according to the imaging region and imaging technique. For this reason, in the storage unit 111 of the radiation imaging apparatus 1, information of pixels PIX for outputting image signals used for generating preview image data out of the plurality of pixels PIX is stored according to each of a plurality of types of instruction information. may be stored.

The console 3 transmits the determined imaging parameters to the radiation imaging apparatus 1 . A plurality of imaging settings may be made in one imaging protocol setting. In the present embodiment, the user sets the imaging protocol using the console 3 after the initial setting of the radiation imaging apparatus 1 is completed. may be used to set the imaging protocol.

The radiation imaging apparatus 1 sets the imaging parameters in the radiation imaging apparatus 1 according to the imaging parameters transmitted from the console 3 (S1405). When the setting of the imaging parameters is completed, the console 3 is notified of the completion of the setting of the imaging parameters.

When the console 3 receives the imaging parameter setting completion from the radiation imaging apparatus 1, it transmits an imaging preparation instruction command to the radiation imaging apparatus 1 (S1405). Upon receiving the imaging preparation instruction command, the radiation imaging apparatus 1 prepares for imaging by activating the radiation detection unit 2, the drive circuit 103, and the readout circuit 107, and notifies the console 3 of the completion of imaging preparation when the preparation is completed. .

When imaging is performed in the radiation imaging apparatus 1 (S1407), the radiation imaging apparatus 1 transfers preview image data to the console 3. FIG. The transferred preview image data may be attached with supplementary information that is information of the pixel unit 212 when the reset operation is stopped. Further, the incidental information may include information indicating that the data is preview image data. In addition, the additional information includes, for example, preview image data generated by the image signal output from the pixel PIX shown in FIG. identification information indicating that the

The console 3 receives the preview image data transferred from the radiation imaging apparatus 1, rearranges the preview image data in a predetermined order according to the designated instruction information and identification information, and causes the display unit 4 to display the preview image data. (S1408). When transferring the preview image data, the console 3 may notify the radiation imaging apparatus 1 of completion of reception for each predetermined transfer unit.

Next, the console 3 receives the main image data from the radiation imaging apparatus 1 . For the main image data, pixels PIX that output the image signals used for generating the main image data may also be determined using the above-described instruction information. In this case, the console 3 rearranges the main image data according to the instruction information, displays it as necessary, and performs appropriate image processing and save processing (S1409). In this case, as described above, image processing may be performed using additional information attached to the main image data. When transferring the main image data, the console 3 may notify the radiation imaging apparatus 1 of reception completion for each predetermined transfer unit, similarly to when transferring the preview image data.

If the next imaging protocol is set in the console 3 (YES in S1410), the next imaging parameter is transmitted to the radiation imaging apparatus 1, and the operation transitions to S1405. On the other hand, if the next imaging protocol is not set (NO in S1410), imaging ends (S1411).

As described above, when the imaging parameters are transmitted from the console 3 to the radiation imaging unit 1, the console 3 transmits to the radiation imaging unit 1 instruction information that instructs the pixels PIX that output the image signals used to generate the preview image data. explained about it. However, it is not limited to this. For example, the console 3 transmits information on a plurality of receivable preview image data to the radiation imaging unit 1 as instruction information, and selects preview image data that the radiation imaging device 1 can handle. and the console 3 may have a negotiation function. Further, for example, in addition to captured images and offset images, user information of the radiation imaging apparatus 1 is stored in the storage unit 111 at the time of factory shipment, etc., and a method of generating preview image data suitable for the user as instruction information is as follows. It may be transferred from the console 3 to the radiation imaging apparatus 1 .

As described above, in the radiation imaging apparatus 1, it is possible to immediately obtain a good preview image while suppressing the circuit scale of the readout circuit 107. FIG. In other words, it is possible to realize the radiation imaging apparatus 1 and the radiation imaging system SYS that are easy to use and that reduce the user's stress during operation.

The invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the claims are appended to make public the scope of the invention.

1: radiation imaging apparatus, 101: detection unit, 103, 214: drive circuit, 108: image processing unit, 203: bias source, Bs: bias line, PIX: pixel, S: conversion element, Sig: column signal line, Vg : drive line

Claims (13)

A plurality of pixels each including a conversion element for converting radiation into an electric charge and arranged to form a plurality of rows and a plurality of columns; a bias source that supplies a bias voltage to the conversion element via a bias line; a detection unit that detects the presence or absence of irradiation of radiation based on the current flowing through the bias line; an image processing unit that generates image data based on signals read from the plurality of pixels via a plurality of column signal lines arranged to extend in a direction of
the plurality of pixels are divided into at least two pixel groups connected to different drive lines among the plurality of drive lines;
each column signal line of the plurality of column signal lines is shared by pixels forming two columns among the plurality of pixels;
While the detection unit detects the start of radiation irradiation, the drive circuit sequentially resets the plurality of pixels via the plurality of drive lines,
After the irradiation of radiation is completed, the image processing unit outputs an image signal output from a pixel group that does not include, among the plurality of pixels, a pixel that was performing a reset operation when the detection unit detected irradiation of radiation. A radiation imaging apparatus characterized by generating preview image data from. After the radiation irradiation is completed, the image processing unit generates main image data from the image signals output from the plurality of pixels,
The main image data is accompanied by first supplementary information related to a pixel that was in a reset operation when the detection unit detected irradiation of radiation,
The first incidental information is information of a drive line that supplies a signal for resetting the plurality of pixels when the detection unit detects irradiation of radiation, and the detection unit detects irradiation of radiation. information on the pixel group to which the pixel that was performing the reset operation among the plurality of pixels at the time belongs, the signal value when the detection unit detects radiation irradiation, and the at least two pixel groups of the plurality of pixels 2. The radiation imaging apparatus according to claim 1, further comprising at least one piece of information about the arrangement of each group of . The image processing unit performs processing including offset correction on the image signal based on the signals read from the plurality of pixels without irradiating radiation to generate the preview image data. 3. The radiation imaging apparatus according to claim 1 or 2. A pixel unit in which a plurality of pixels for converting radiation into electric charges are arranged in a plurality of rows and a plurality of columns; A radiation imaging apparatus including a drive circuit that controls pixels, a detection unit that detects whether or not radiation is irradiated, and an image processing unit that generates image data based on signals read from the plurality of pixels. There is
the plurality of pixels are divided into at least two pixel groups connected to different drive lines among the plurality of drive lines;
Until the detection unit detects the start of radiation irradiation, the driving circuit moves the plurality of pixels for each pixel group from the first row side toward the last row side in the column direction in the pixel unit. Reset the pixels,
After the irradiation of radiation is completed, the image processing unit selects a row in which a reset pixel that was performing a reset operation when the detection unit detected irradiation of radiation among the plurality of pixels is arranged as a reset row. An image signal output from at least one row of pixels arranged between the row next to the reset row and the last row among the first image signals output from the pixel group including the reset pixels. and image signals output from pixels arranged between the first row and the reset row among second image signals output from pixel groups not including the reset pixels. A radiation imaging apparatus that generates image data. After the radiation irradiation is completed, the image processing unit generates main image data from the first image signal and the second image signal,
The main image data is accompanied by first supplementary information related to a pixel that was in a reset operation when the detection unit detected irradiation of radiation,
The first incidental information is information of a drive line that supplies a signal for resetting the plurality of pixels when the detection unit detects irradiation of radiation, and the detection unit detects irradiation of radiation. information on the pixel group to which the pixel that was performing the reset operation among the plurality of pixels at the time belongs, the signal value when the detection unit detects radiation irradiation, and the at least two pixel groups of the plurality of pixels 5. The radiation imaging apparatus according to claim 4, further comprising at least one piece of information about the arrangement of each group of . 3. The image processing unit, when generating the preview image data, performs processing including offset correction based on signals read from the plurality of pixels without irradiating radiation. 6. The radiation imaging apparatus according to 4 or 5. further comprising a storage unit that stores an offset image based on the signals read from the plurality of pixels without irradiating radiation;
7. The radiation imaging apparatus according to claim 3, wherein the image processing unit performs offset correction based on the offset image. the at least two pixel groups comprise a first pixel group and a second pixel group;
pixels belonging to the first pixel group among the plurality of pixels and pixels belonging to the second pixel group among the plurality of pixels are alternately arranged in the row direction;
2. The pixels belonging to the first pixel group among the plurality of pixels and the pixels belonging to the second pixel group among the plurality of pixels are arranged alternately in the column direction. 8. The radiation imaging apparatus according to any one of items 1 to 7. the at least two pixel groups include a first pixel group and a second pixel group;
pixels belonging to the first pixel group among the plurality of pixels and pixels belonging to the second pixel group among the plurality of pixels are alternately arranged in the column direction;
5. The pixels belonging to the first pixel group among the plurality of pixels or the pixels belonging to the second pixel group among the plurality of pixels are arranged continuously in the row direction. 8. A radiation imaging apparatus according to any one of claims 6 to 7 and claim 7 depending on claim 6. The preview image data is accompanied by second supplementary information related to pixels that were reset when the detection unit detected irradiation of radiation,
The second incidental information is information of a drive line that supplies a signal for resetting the plurality of pixels when the detection unit detects irradiation of radiation, and the detection unit detects irradiation of radiation. information on the pixel group to which the pixel that was performing the reset operation among the plurality of pixels belongs, information on arrangement of each of the at least two pixel groups of the plurality of pixels, information on the arrangement of each group of the plurality of pixels, and at least one of information on whether or not pixels outputting image signals used to generate preview image data are thinned out, and information on pixels outputting image signals used to generate preview image data among the plurality of pixels; 10. The radiation imaging apparatus according to any one of claims 1 to 9, characterized in that it contains two pieces of information. a radiation imaging apparatus according to any one of claims 1 to 10;
a processor that processes signals output from the radiation imaging apparatus;
A radiation imaging system comprising: The processor transmits instruction information instructing a method of generating the preview image data to the radiation imaging apparatus,
12. The radiation according to claim 11, wherein the radiation imaging apparatus determines, among the plurality of pixels, pixels for outputting image signals used for generating the preview image data, according to the instruction information. imaging system. The radiation imaging apparatus includes a storage unit storing information of pixels outputting image signals used for generating the preview image data among the plurality of pixels according to each of the plurality of types of the instruction information. 13. The radiographic imaging system of claim 12, comprising:

Images