JP2021186352A - Radiation image photographing apparatus, radiation image photographing system, controller, and program - Google Patents

Abstract

To provide a radiation image photographing apparatus, a radiation image photographing system, a controller, and a program, capable of performing photographing at saved costs and with high image quality even when the radiation image photographing apparatus and a radiation generator cannot synchronize with each other.SOLUTION: A radiation image photographing apparatus includes a plurality of radiation detection elements arranged in a two-dimensional shape correspondingly to respective pixels of an image to generate electric charges and, on the basis of an electric charge generated by each of the plurality of radiation detection elements, reads a signal value of each pixel to create an image. The radiation image photographing apparatus comprises: control means capable of performing a continuous photographing mode of continuously generating images by repeating charge storage operation and reading operation at predetermined intervals; detection means for detecting the presence/absence of radiation exposure; and correction information storage means for storing, as an offset image to be used for offset correction, one or more images acquired at timing before the detection means detecting radiation exposure.SELECTED DRAWING: Figure 5

Description

The present invention relates to a radiographic imaging device, a radiographic imaging system, a control device and a program.

Various radiographic imaging devices have been developed in which electric charges are generated by a radiation detecting element according to the dose of irradiated radiation and the generated electric charges are read out as image data.
It is also possible to acquire an image (moving image) that captures the movement of a living body by using a radiation imaging device.

Since the radiation imaging device can be configured as a panel-shaped portable type, it is not only used in association with a specific radiation generator in the imaging room, but also in combination with a portable type radiation generator. It is expected to be used in various situations, such as being used in a radiological examination car or being used to photograph a patient lying on a bed or the like. Therefore, it is possible that the radiation imaging device and the radiation generator cannot be synchronized with each other. Further, even if it has a configuration that can be synchronized, it may not be possible to synchronize well due to poor communication or the like.

In this regard, in Patent Document 1, the control unit determines whether or not it is possible to detect the rise of a plurality of radiation pulses generated by the radiation generator, and based on the determination result, the radiation imaging device (Patent Document 1). In 1, the operation mode of "FPD") is a pulse irradiation compatible mode that detects the rising and falling edges of the radiation pulse and synchronizes the timing of the charge accumulation operation with the detected timing, and detects the rising and falling edges of the radiation pulse. Disclosed is a technique for appropriately setting a continuous irradiation compatible mode in which a charge accumulation operation is executed at predetermined time intervals without using the above.

Further, Patent Document 2 has a continuous shooting mode for shooting a still image without distinguishing between still image shooting and moving image shooting, in addition to a still image mode for shooting a still image and a moving image mode for shooting a moving image. If there is no instruction to shoot an image or a movie, the image data can be read out for each frame by shooting in the continuous shooting mode, and both still image shooting and movie shooting are supported. The technology that enables it is disclosed.

By the way, in a radiation imaging apparatus, even in a state where no radiation is applied, dark charges are generated in each radiation detection element due to thermal excitation by the heat of the radiation detection element, and the electric charges accumulated in the radiation detection element are dark. The offset due to the electric charge is included. Therefore, in order to acquire a high-quality radiation image, an offset image acquisition process that normally reads data for an offset due to dark charge (hereinafter referred to as "offset image") from each radiation detection element without irradiating radiation is performed. This is performed before or after the radiation image acquisition process for acquiring a radiation image (also referred to as a “photographed image”) by accumulating and reading out the electric charge generated by the irradiation of radiation in each radiation detection element. Then, by subtracting the offset image from the radiation image (photographed image) acquired by the radiation image acquisition process, offset correction is performed to remove the offset portion due to the dark charge from the radiation image (photographed image).

For example, Patent Document 3 describes that an average of a plurality of offset images (multiple offset outputs) is stored in a storage unit in advance, and the offset images (offset output values) are used for offset correction. ing.

Japanese Unexamined Patent Publication No. 2017-018705 International Publication No. 2017/013896 Japanese Unexamined Patent Publication No. 2005-287733

However, in order to perform appropriate offset correction, use the offset image acquired immediately before taking the radiation image (photographed image) (main shooting), that is, immediately before the start of exposure of the radiation generator. Is preferable.
As described in Patent Document 3, when an offset image saved in advance is used, an appropriate offset correction cannot be performed on the radiation image (photographed image), and the image quality of the photographed image deteriorates. There is a risk.

Further, in the case where the radiation imaging device and the radiation generator cannot operate in synchronization as described in Patent Documents 1 and 2, the timing of the start of exposure is unknown, so the frame immediately before the exposure is determined. It is difficult to obtain an appropriate offset image. In this regard, Patent Documents 1 and 2 do not mention acquiring an offset image and performing offset correction.

An object of the present invention is a radiation imaging device, a radiation imaging system, a control device, and a program capable of performing high-quality imaging at low cost even when the radiation imaging device and the radiation generating device cannot be synchronized. Is to provide.

In order to solve the above problems, the radiographic imaging apparatus according to claim 1 is used.
It has a plurality of radiation detection elements that are arranged in a two-dimensional manner corresponding to each pixel of the image and generate a charge, and the signal value of each pixel is read out based on the charge generated by each of the plurality of radiation detection elements. It is a radiation imaging device that generates images.
A control means capable of carrying out a continuous shooting mode in which the image is continuously generated by repeating the charge accumulation operation and the read-out operation at predetermined time intervals.
A detection means that detects the presence or absence of radiation exposure,
A correction information storage means that stores one or more images acquired at a timing before the detection means detects radiation exposure as an offset image used for offset correction.
It is characterized by having.

Further, the radiographic imaging system according to claim 11 is
It has a plurality of radiation detection elements that are arranged in a two-dimensional manner corresponding to each pixel of the image and generate a charge, and the signal value of each pixel is read out based on the charge generated by each of the plurality of radiation detection elements. It is a radiographic imaging system equipped with a radiographic imaging device that generates images and a console.
A control means capable of carrying out a continuous shooting mode in which the image is continuously generated by repeating the charge accumulation operation and the read-out operation at predetermined time intervals.
A detection means that detects the presence or absence of radiation exposure,
A correction information storage means that stores one or more images acquired at a timing before the detection means detects radiation exposure as an offset image used for offset correction.
A captured image storage means that stores an image acquired at a timing after the detection means detects radiation exposure as a captured image, and a captured image storage means.
An image correction means for performing offset correction on the captured image stored in the captured image storage means using the offset image stored in the correction information storage means.
It is characterized by having.

Further, the radiographic imaging system according to claim 18 is
It is provided with a plurality of radiation detection elements that are arranged in a two-dimensional manner corresponding to each pixel of the image and generate a charge, and the signal value of each pixel is read out based on the charge generated by each of the plurality of radiation detection elements. It is a radiation imaging system including a radiation imaging device that generates an image, a console, and a radiation generator that irradiates radiation toward the radiation imaging device.
A control means capable of carrying out a continuous shooting mode in which the image is continuously generated by repeating the charge accumulation operation and the read-out operation at predetermined time intervals.
A detection means that detects the presence or absence of radiation exposure,
A correction information storage means that stores one or more images acquired at a timing before the detection means detects radiation exposure as an offset image used for offset correction.
A captured image storage means that stores an image acquired at a timing after the detection means detects radiation exposure as a captured image, and a captured image storage means.
An image correction means for performing offset correction on the captured image stored in the captured image storage means using the offset image stored in the correction information storage means.
It is characterized by having.

Further, the control device according to claim 19 is
An image storage means for storing an image acquired by using a radiographic imaging device, and
A detection information storage means for holding the detection information of the start of radiation exposure to which the irradiation of radiation to the radiation imaging device is started, and the detection information storage means.
Based on the detection information stored in the detection information storage means, the image is an offset image acquired at the timing before the radiation exposure is detected, or is acquired at the timing after the radiation exposure is detected. A discriminating means for discriminating whether the image is a photographed image and
An image correction means for performing offset correction using the offset image on the captured image, and
It is characterized by having.

Further, the program according to claim 20 is
On the computer
An image storage function that saves images acquired using a radiation imaging device, and
A detection information storage function that retains the detection information of the start of radiation exposure when the radiation imaging device is started to be irradiated, and the detection information storage function.
Based on the detection information stored by the detection information storage function, the image is an offset image acquired at the timing before the radiation exposure is detected, or is acquired at the timing after the radiation exposure is detected. A discrimination function that determines whether the image was taken and
An image correction function that performs offset correction using the offset image on the captured image, and
It is characterized by realizing.

According to the present invention, even when the radiation imaging apparatus and the radiation generating apparatus cannot be synchronized, high-quality imaging can be performed at low cost.

It is a main part block diagram which shows typically the whole structure of the radiation imaging system in this embodiment. It is a block diagram which shows the equivalent circuit of a radiation imaging apparatus. It is a flowchart which shows the whole procedure of the radiographic image taking method in this embodiment. It is a flowchart which shows the processing procedure of the continuous shooting mode in FIG. It is explanatory drawing which shows typically the relationship between the timing of irradiation and the timing of image acquisition in the continuous photographing mode in this embodiment. It is explanatory drawing which shows typically the case where the exposure start is detected during a reading operation. It is explanatory drawing which shows typically the handling of an image when the start of exposure is detected during a reading operation. It is explanatory drawing which shows typically the case where the start of exposure is detected during charge accumulation. It is a flowchart which shows an example of the procedure of the exposure end detection. It is explanatory drawing which shows typically the case where the end of exposure is detected during a reading operation. It is explanatory drawing which shows typically the case where the end of exposure is detected during charge accumulation. It is a graph which shows the example of the change of the radiation output intensity in the time axis direction. It is a flowchart which shows an example of the procedure of output fluctuation correction. It is a flowchart which shows the processing procedure of the still image shooting mode in FIG. It is a flowchart which shows the processing procedure in the case of taking a picture in a continuous picture mode in cooperation with a radiation generator which can communicate. It is a flowchart which shows the processing procedure in the case of taking a picture in a pulse shooting mode in cooperation with a radiation generator which can communicate. It is a flowchart which shows the processing procedure in the case of taking a picture in a still image shooting mode in cooperation with a radiation generator which can communicate. It is a main part block diagram which shows the main part structure of the console in one modification of this embodiment.

Hereinafter, an embodiment of a radiation imaging device, a radiation imaging system, a control device, and a program according to the present invention will be described with reference to FIGS. 1 to 17.
However, although the embodiments described below are provided with various technically preferable limitations for carrying out the present invention, the technical scope of the present invention is not limited to the following embodiments and illustrated examples. No.

[Configuration of radiation imaging system]
First, a schematic configuration of the radiation imaging system 100 according to the present embodiment will be described. FIG. 1 is a configuration diagram of a main part schematically showing an overall configuration of a radiation imaging system 100.

As shown in FIG. 1, the radiographic imaging system 100 of the present embodiment includes a radiographic imaging apparatus 1, a console 50, and a radiation generator 60.
The radiation imaging apparatus 1 and the console 50 can communicate with each other by a wireless method or a wired method via various communication networks.
In the present embodiment, an example will be described in which the acquisition of a radiographic image (hereinafter, also referred to as a “captured image”) and the correction of the captured image can be performed by the radiographic image capturing apparatus 1 alone.

The radiological imaging system 100 is composed of a radiographic imaging device 1 and a console 50, and may be used in combination with a radiation generator outside the system, or may be used in combination with a hospital information system (HIS) (not shown). , Radiology Information System (RIS), Picture Archiving and Communication System (PACS), image analysis device, etc. may be able to be connected.

[Radiation generator]
Although not shown, the radiation generator 60 has a voltage corresponding to preset irradiation conditions (tube voltage, tube current, irradiation time (mAs value), etc.) based on the operation of the irradiation instruction switch. It is provided with a generator for applying a voltage, a radiation source 61 for generating a dose of radiation (for example, X-ray) corresponding to the applied voltage when a voltage is applied from the generator, and the like.
As shown in FIG. 1, the radiation generator 60 is arranged so as to face the radiation image capturing device 1 via the subject M, and generates radiation in an manner corresponding to the radiographic image (still image / dynamic image) to be captured. The radiation imaging device 1 is irradiated with radiation.

In this embodiment, it is possible to shoot a moving image in addition to shooting a general still image, and a radiation generator 60 corresponding to this is used.
When performing movie shooting, there is also a method of pulsing radiation, but radiation generators that can handle pulse irradiation are not widely prepared in the shooting facility, and even if pulse irradiation is possible, pulse is used. There may be variations in the output of. A device capable of outputting a neatly aligned pulse is expensive, and if the radiation generator 60 is limited to such a device, it is not possible to flexibly shoot a moving image.

Therefore, in the present embodiment, the device is not limited to a device capable of supporting pulse irradiation, and can be applied as a radiation generator 60 as long as the imaging time (radiation irradiation time) can be set in about 1 second or longer. That is, even with a general radiation generator for still image shooting, if the shooting time is set to about 1 second or longer, it is possible to shoot a moving image by seeing this as continuous irradiation.
Further, the radiation generator 60 may be installed in an imaging room (not shown), or may be mounted on a so-called medical examination vehicle or the like together with the radiation imaging apparatus 1 or the console 60 and configured to be movable. Etc., it may be a portable type.

〔console〕
The console 60 has various shooting conditions (tube voltage, tube current, irradiation time (mAs value), frame rate, physique of the subject, etc., based on the shooting order information acquired from other systems (HIS, RIS, etc.) and the operation by the user. , Presence / absence of grid, etc.) is set in the radiation generator 60 and the radiation image capturing device 1, and the image generated by the radiation imaging device 1 is subjected to predetermined image processing, and is used for a PC or a dedicated image. It is composed of the following devices.

[Radiation imaging device]
As shown in FIG. 1, for example, the radiation imaging apparatus 1 is configured in a panel shape with a housing, and is loaded into a holder or the like of a support base 1a for use.
The configuration of the radiation imaging apparatus 1 is not particularly limited. For example, the radiation imaging apparatus 1 may be integrally formed with the support base 1a or the like, or may be configured to be portable and detachable from the holders of various support bases. In addition, even if it is not loaded in a holder or the like, it is used as a single body for shooting, for example, by touching the body of the patient who is the subject, or by inserting it between the patient lying on the bed and the bed. good.

The radiation imaging apparatus 1 has a plurality of radiation detection elements 7 (see FIG. 2) that are arranged in a two-dimensional manner corresponding to each pixel of an image and generate a charge, and each of the plurality of radiation detection elements 7 is generated. An image is generated by reading out the signal value of each pixel based on the generated charge.
When the radiation imaging device 1 is irradiated with radiation from the above-mentioned radiation generator 60, the radiation imaging device 1 generates charges corresponding to the received radiation in the plurality of radiation detection elements 7, and the signal value of each pixel is based on these charges. A radiation image (photographed image) is generated by reading out.
Further, in the radiation imaging apparatus 1, even in a state where no radiation is irradiated, electric charges (dark charges) are generated in each radiation detection element 7 due to thermal excitation by the heat of the radiation detection element 7. The data obtained by reading out the dark charge accumulated in the radiation detection element 7 without irradiating the radiation from each radiation detection element 7 is the data for the offset used for the offset correction described later (hereinafter referred to as "offset image"). .).

Here, a specific configuration of the radiographic imaging apparatus 1 of the present embodiment will be described with reference to FIG. 2.
As shown in FIG. 2, the radiation imaging apparatus 1 includes a detection unit P in which a plurality of radiation detection elements 7 are arranged in a two-dimensional shape (matrix shape). A bias wire 9 is connected to each radiation detection element 7, and a reverse bias voltage is applied from the bias power supply 14 via the bias wire 9 and the connection 10 thereof.

Further, a TFT (Thin Film Transistor) 8 is connected to each radiation detection element 7 as a switch element, and the TFT 8 is connected to a signal line 6. Then, in each radiation detection element 7, an electric charge corresponding to the dose of radiation radiated through the subject M (not shown) is generated in each radiation detection element 7.

Further, in the scanning drive means 15, the on voltage and the off voltage supplied from the power supply circuit 15a via the wiring 15c are switched by the gate driver 15b and applied to the lines L1 to Lx of the scanning line 5. Then, each TFT 8 is turned off when an off voltage is applied via the scanning line 5, cuts off the conduction between the radiation detection element 7 and the signal line 6, and accumulates electric charges in the radiation detection element 7. .. Further, when an on-voltage is applied via the scanning line 5, the on-state is turned on, and the electric charge accumulated in the radiation detection element 7 is discharged to the signal line 6.

Each signal line 6 is connected to each read circuit 17 in the read IC 16. Then, during the reading process of the signal value D, the on-voltage is sequentially applied from the gate driver 15b to each of the lines L1 to Lx of the scanning line 5. Then, when the TFT 8 is turned on, electric charges flow from the radiation detection element 7 into the readout circuit 17 via the TFT 8 and the signal line 6, and the amplifier circuit 18 outputs a voltage value according to the amount of the electric charges that have flowed in.

The correlated double sampling circuit (described as “CDS” in FIG. 2) 19 reads out and outputs the voltage value output from the amplifier circuit 18 as an analog value signal value D, and outputs the output signal value D. Is sequentially transmitted to the A / D converter 20 via the analog multiplexer 21, is sequentially converted into the signal value D of the digital value by the A / D converter 20, and is sequentially stored in the storage means 23. ..
When a charge (dark charge) is generated in each radiation detection element 7 due to thermal excitation or the like, the signal value is read out by the same processing.

The control means 22 is composed of a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a computer in which an input / output interface or the like is connected to a bus, an FPGA (Field Programmable Gate Array), or the like (not shown). Has been done. It may be composed of a dedicated control circuit.

In the present embodiment, the control means 22 of the radiation imaging apparatus 1 functions as a control means for performing an imaging operation corresponding to at least a continuous imaging mode. In the continuous shooting mode, an image is continuously generated by repeating a charge accumulating operation and a reading operation at predetermined time intervals.
In addition, the control means 22 functions as a detection means for detecting the presence or absence of radiation exposure by the radiation generator 60, and an image correction means for performing offset correction using an offset image on the captured image.
Further, in the present embodiment, the control means 22 can carry out a still image shooting mode in which images are generated one by one in addition to the continuous shooting mode, and the control means 22 can be carried out in light of various conditions. It also functions as a shooting mode determination means for determining a suitable shooting mode. Various conditions for determining the feasible shooting mode include, for example, the remaining battery level of the built-in power supply 24 and the remaining memory level of the storage means 23.

The conditions considered by the control means 22 are not limited to this. For example, if there is an agreement that continuous imaging with the radiographic imaging apparatus 1 is not permitted unless a predetermined license is granted, the facility performing the imaging has not obtained the license (license by the control means 22). If the information cannot be confirmed), it may be determined that the control means 22 can only perform the still image shooting mode (cannot perform the continuous shooting mode). Further, in the case of the continuous shooting mode, a lag tends to remain due to the radiation of continuous irradiation. Therefore, when the shooting interval is shorter than the predetermined interval, it may be determined that the control means 22 cannot yet perform the next continuous shooting. Further, in the case where the image data is finally transmitted from the radiation image capturing device 1 to an external device such as the console 50, the control means 22 determines the communication state and has a relatively large capacity obtained by the continuous imaging mode. It may be determined whether or not the continuous shooting mode can be implemented based on whether or not a large image data can be transmitted.
Each of these functions of the control means 22 in the present embodiment will be described in detail later.

Further, as described above, the control means 22 controls the application of the reverse bias voltage from the bias power supply 14 to each radiation detection element 7, and controls the operation of the scanning drive means 15, the readout circuit 17, and the like. The signal value D read from the radiation detection element 7 is read out, and the read signal value D is stored in the storage means 23, or the stored signal value D is sent to the outside via the communication unit 30. It is designed to control each part of the radiographic imaging apparatus 1 such as transfer.

Further, the control means 22 can control the on / off of the power supply of the radiographic image capturing apparatus 1. The control means 22 includes a microcomputer (not shown) that is driven by a very small power supplied from the built-in power supply 24 even when the power of the radiation imaging device 1 is off, and the control means 22 includes a radiation imaging device 22. It is configured so that the switching from the power off to the power of the radiographic image capturing apparatus 1 can be controlled even when the power of 1 is off.

Further, a storage means 23 composed of a SRAM (Static RAM), a SDRAM (Synchronous DRAM), a NAND flash memory, or the like is connected to the control means 22.
The storage means 23 of the present embodiment is used as a correction information storage means and a detection means for storing an image acquired at a timing before the control means 22 as a detection means detects radiation exposure as an offset image used for offset correction. The control means 22 functions as a photographed image storage means for storing an image acquired at the timing after the radiation exposure is detected as a photographed image.
In the other storage means 23, when the control means 22 as the detection means detects the presence or absence of radiation exposure, the radiation exposure to the radiation imaging device 1 by the radiation generator 6 is started. It also functions as a detection information storage means for holding start detection information.
The matters stored in the storage means 23 are not limited to those exemplified here. Some of these may be stored, or other items may be stored.

Further, a built-in power supply (battery) 24 composed of a lithium ion capacitor or the like is connected to the control means 22. Further, the control means 22 is connected to a communication unit 30 for communicating with the outside by a wireless method or a wired method via the antenna 29 and the connector 27.

In addition, the control means 22 of the present embodiment is connected to the operation means 31, the notification means 32, and the like. It is not essential to provide the operating means 31 and the notifying means 32.
The operating means 31 is composed of various switches such as a power switch and a mode setting switch as a setting means for selecting and setting a shooting mode.
The operating means 31 may be a button, a changeover switch, or the like provided on the surface or side surface of the housing of the radiographic image capturing apparatus 1, or if it includes a display unit or the like having a touch panel, the touch panel may be used. May be.
The operating means 31 as the setting means can set either a continuous shooting mode or a still image shooting mode, and when any of the shooting modes is set by the operating means 31 as the setting means, the control means. 22 performs a shooting operation according to a shooting mode set by the setting means.

The notification means 32 is composed of, for example, a display means, a voice output means including a speaker or the like, a vibration generating means including a vibration motor or the like. At least one type of notification means 32 may be provided, and a combination of a plurality of types may be used.
When a display means is provided as the notification means 32, for example, a monitor that displays an image such as an LCD (Liquid Crystal Display) or a CRT (Cathode Ray Tube) (not shown) is used to display a configuration display unit, an indicator, a lamp, or the like on the surface of the housing. Provided on the side surface, etc.

The notification means 32 of the present embodiment has a function as a first notification means for notifying an operating state related to shooting, as a shooting mode determination means, and as a second notification means for notifying a determination result by the control means 22. The first notification means and the second notification means may be the same or may be provided separately. For example, a lamp or an indicator as a first notifying means and a lamp or an indicator as a second notifying means may be separately provided. Further, the first notification means may be configured by a lamp or an indicator, and the second notification means may be configured by a display unit including an LCD, a CRT, or the like.

The operation state related to shooting is, for example, each state such as preparation for shooting, shooting, transfer of data (for example, data of shot image, etc.), and a display or a lamp indicating the state of the radiation image shooting device 1. Notify the user by lighting etc.
The judgment result of the shooting mode is, for example, a judgment result that both the still image shooting mode and the moving image shooting mode can be carried out, only the still image shooting mode is possible, and neither shooting mode can be carried out. Notify the user by display or the like.
If there is a shooting mode that cannot be performed, the notification means 32 may notify (for example, display it on the display unit) together with the reason why it cannot be performed (for example, insufficient battery level, insufficient memory level, etc.). .. It is preferable that the reason why the implementation cannot be performed is indicated by an easy-to-understand icon or the like so that the user can understand at first glance.

[Operation of radiation imaging device]
Next, the operation of the radiographic imaging apparatus 1 (radiation imaging system 100 including the radiographic imaging apparatus 1) in the present embodiment will be described.

First, as shown in FIG. 3, by operating the operating means 31 as the setting means, the radiation image capturing device 1 sets whether the imaging mode is the continuous imaging mode or the still image imaging mode. (Step S1).
The control means 22 determines whether or not the set shooting mode is the continuous shooting mode (step S2). When the continuous shooting mode is set (step S2; YES), whether or not the set shooting mode (that is, the continuous shooting mode) can be executed in light of various conditions such as the remaining battery level. (Step S3).

When it is determined that the continuous shooting mode is feasible (step S3; YES), the control means 22 controls each unit to perform the shooting operation in the continuous shooting mode (step S4).
On the other hand, when it is determined that the continuous shooting mode is not feasible (step S3; NO), the control means 22 informs the second notification means that the continuous shooting mode is not feasible and the reason thereof. Notify the user by the notifying means 32 (step S5).

On the other hand, even when the continuous shooting mode is not set (that is, when the still image shooting mode is set, step S2; NO), the shooting mode is set in light of various conditions such as the remaining battery level. (That is, it is determined whether or not it is possible to carry out the still image shooting mode) (step S6). When it is determined that the still image shooting mode is feasible (step S6; YES), the control means 22 controls each unit to perform the shooting operation in the still image shooting mode (step S7).
On the other hand, when it is determined that the still image shooting mode is not feasible (step S6; NO), the control means 22 determines that the still image shooting mode is not feasible and the reason thereof. The user is notified by the notification means 32 as the notification means (step S8).

When any of the shooting modes is set, the notification means 32 notifies the user of the current operating state in the set shooting mode as the first notification means for notifying the operating state related to shooting. You may.
The operating state is, for example, a state in which shooting is being prepared, a shooting is possible, a shooting is in progress, an image data is being transferred, and the like. Here, "preparing for shooting" means, for example, when it is set to acquire 16 offset images in the continuous exposure mode, the main shooting (shooting by irradiating the radiation to acquire the shot image) while the offset image is acquired. ) Cannot be performed, and this time is in preparation for shooting.
The method of notifying the operating state is not particularly limited, but for example, when shooting is being prepared to acquire an offset image, the color of the lighting part of the indicator may change as a predetermined number of offset images are acquired. , The blinking status may change.
The first notification means may be the same as the second notification means, or may be provided separately.
By notifying the operating state, for example, it is possible to prevent erroneous shooting such as accidental exposure during preparation for shooting.

FIG. 4 is a flowchart showing a procedure when the continuous imaging mode is implemented, and FIG. 5 is an explanatory diagram illustrating the relationship between the output of radiation from the radiation generator and the driving of the radiation imaging apparatus.
When the continuous shooting mode is implemented, a preparatory operation before shooting is performed as shown in FIG. 4 (step S11). Specifically, as a preparatory operation, in the radiation imaging apparatus 1, in the detection unit P composed of the radiation detection element 7, the electric charge accumulation and the reading operation of the signal value based on the accumulated electric charge are repeated. Then, the read signal value (image signal value) is acquired as an image (step S12).

As shown in FIG. 5, the signal value data accumulated and read out before the radiation exposure is an offset image which is dark charge information.
The control means 22 determines at any time whether or not the start of exposure is detected (step S13), and updates the offset image to the latest acquired image at any time until the start of exposure is detected (step S13; NO). Then, it is stored in the storage means 23 as the correction information storage means (step S14), and the process is repeated by returning to step S12.
In the present embodiment, the control means 22 detects the start of exposure (that is, the timing when the radiation output changes from OFF to ON in FIG. 5), so that the image acquired before the start of exposure is used as an offset image and exposed. The image acquired after the start of shooting is determined to be the captured image.

Any method may be used to detect the start of exposure.
For example, a radiation sensor (X-ray sensor) for detecting radiation may be mounted inside and outside the radiation imaging device 1, and a judgment may be made by looking at the output of this radiation sensor. Further, in the case of continuous shooting, since the image signal value itself is read out before the start of exposure, the read image signal value (pixel value) may be used for determination. When using an image signal value (pixel value), for example, a signal value having a certain threshold value is set, and when an image signal value (pixel value) exceeding this value is read out, it is determined that exposure has started.
In this way, by detecting the timing of the start of radiation exposure by the control means 22, it is possible to correctly determine how far the image is before the start of exposure (offset image) and where is the radiation image (photographed image). be able to. Therefore, even if the radiation image capturing device 1 and the radiation generating device 60 cannot be synchronized and cooperated with each other, as much as possible at the timing when the captured image is acquired every time the imaging (main imaging by irradiating radiation) is performed. The offset image acquired at a close timing can be acquired, the accuracy of the offset correction is improved, and the image quality of the captured image is improved.

It is possible to acquire the offset image at the timing after the start of exposure, but in this case, the offset image contains a lag component such as the afterglow of the image due to the already exposed radiation. If correction is performed using an offset image affected by such exposure, the accuracy of correction deteriorates. Therefore, it is preferable to acquire an offset image immediately before the main shooting before the start of exposure.

The destination for storing the offset image may be the storage means 23 inside the radiographic image capturing apparatus 1, or various storage means provided outside the radiographic imaging apparatus 1. For example, it may be transmitted to the console 50 or the like and stored at the destination.
Further, the offset image used for the offset correction may be one image or a plurality of images.
For example, as shown in FIG. 5, when there are a plurality of images acquired before the detection of the start of exposure, one of them that is closest to the timing of the start of exposure may be selected as an offset image, or a plurality of images may be selected. (In the example of FIG. 5, three images are acquired by accumulating and reading three sets before the detection of the start of exposure) may be used as an offset image.
When a plurality of images are used, for example, an offset image is generated by averaging the images. Further, the case is not limited to the case of averaging, and a median value may be taken for each pixel, a mode value may be calculated, or a weighted average may be used to generate one offset image from a plurality of images.
When a plurality of images are used in this way, random noise can be removed, so that fixed pattern noise can be extracted with high accuracy, and the accuracy of offset correction is improved.

Here, the timing at which the start of radiation exposure is detected and the handling of images at the boundary before and after the start of radiation exposure will be described in detail with reference to FIGS. 6 and 7.
As in the example shown in FIG. 5, when the start of exposure is detected at the exact boundary between the charge accumulation operation and the read operation, the image accumulated and read before the start of exposure is an offset image. The image that has been accumulated and read out after the start of exposure may be treated as a captured image. However, the start of exposure is not always detected exactly at the boundary of the set.
As the detection timing, it is assumed that the charge accumulation operation and the read operation are in progress.

FIG. 6 is a diagram schematically showing a case where the timing at which the start of exposure is detected is during the signal value reading operation in the radiation image capturing apparatus 1.
In this case, the image (dark image) accumulated and read before the start of exposure may be treated as an offset image, and the image accumulated and read after the start of exposure may be treated as a captured image. The handling of the image that was being read when it was detected becomes a problem.
In the example shown in FIG. 6, when the start of exposure is detected during the reading operation in the storage and reading of the fourth set, the image being read may be discarded or used as a captured image. If it can be done, it may be stored as a captured image.

For example, in the case of the operation of sequentially reading the image signal value from the upper end of the image on the panel, if the exposure is started during the reading, the line that has already been read by the time the exposure is started. Is an unexposed image (dark image), and the rows read out after the start of exposure are exposed images, and the unexposed area and the exposed area coexist in one frame. Become.
In such a case, the image may be discarded.
When such an image is used as a captured image, for example, it is conceivable to connect an exposure region that can be used as a captured image and the next image and use it as one image.

That is, for example, as shown in FIG. 7, when the start of exposure is detected while reading the image signal value of the nth line of a certain frame image N, from the nth line to the last line of the image. The image of the frame image N is saved as the image of the frame image N, and when the image signal value of the next frame image N + 1 is read out, the images from the nth line to the last line of the frame image N are stored in the frame image N + 1. The images from the first row to the n-1th row are combined to form one captured image.
In this case, the reading start position is shifted so that the nth line becomes the first reading line for the subsequent frames.

If the start of exposure is detected while reading the image signal value of the nth line, the images from the n + 1th line to the last line are displayed from the first line to the nth line of the next frame image. You may combine with the image of 1 to form one photographed image.
Further, the image from the n (or n + 1) th row to the last row of a certain frame image N is averaged with the image from the n (or n + 1) th row to the last row of the next frame image N + 1, and the frame image N + 1 Then, the subsequent frames may be read from the first line without shifting the read start position.

On the other hand, FIG. 8 is a diagram schematically showing a case where the timing at which the start of exposure is detected is during the accumulation of electric charges in the radiation imaging apparatus 1.
When the start of exposure is detected during the accumulation, the signal value is read high when it is detected at the beginning of the accumulation, and the signal value is considerably low when it is detected at the end of the accumulation.
Therefore, whether or not to discard such an image is determined, for example, by the signal value of the image. That is, for example, a predetermined threshold value is set for the read image signal value, and when the threshold value is exceeded, it is stored as a valid captured image, and when the image signal value is lower than the threshold value, it is discarded. do. Even if the signal value is low, such an image cannot be used as an offset image because it has an exposure component, and is discarded except when it is worthy of being treated as a captured image.

Up to this point, as shown in FIG. 5, the case of acquiring an image by alternately performing storage and reading has been described. However, when shooting at a high frame rate such as 30 fps, the storage time is not provided. You may. That is, in the reading operation, the rows are read one by one in order from the row above the detection unit P, but the row in which the reading is not performed is in a state where the switch is closed. While one row is being read, the other rows with the switch closed are substantially similar to accumulating. Therefore, even if the storage time for closing all the switches is not separately provided, the storage and reading are repeated line by line. If the storage time is not provided separately, the processing time can be shortened and the frame rate can be increased accordingly.

In the present embodiment, the case where the offset image is acquired before the start of exposure and the offset image is updated to the latest one and saved each time is illustrated, but the offset image is not limited to this.
For example, the offset image to be used for offset correction may be determined later by storing all the memory capacity up to the upper limit of the memory capacity of the storage means 23 and observing the timing of the start of exposure from the detection result or the like after the end of the photographing operation.
If there is enough memory capacity, all the images from before the start of exposure to the end of exposure are stored, and after the end of shooting, based on the detection information detected by the control means 22 as the detection means, The acquired image may be discriminated into an offset image and a captured image before and after the timing of the start of exposure.

Returning to FIG. 4, when the start of exposure is detected (step S13; YES), the control means 22 acquires the subsequent images as captured images (step S15), and stores the images as captured image storage means. It is stored in 23 (step S16).
The control means 22 determines at any time whether or not the end of exposure is detected (step S17), and returns to step S15 to repeat the acquisition process of the captured image until the end of exposure is detected (step S17; NO). ..
On the other hand, when it is detected that the exposure has ended (step S17; YES), the offset image acquired before the start of the exposure is used to perform offset correction on the captured image (step S18).

FIG. 9 is a flowchart showing a procedure for detecting the end of exposure.
After detecting the start of exposure, as shown in FIG. 9, the control means 22 acquires a photographed image (step S21) and stores the photographed image in the storage means 23 as the photographed image storage means (step S22).
Then, as in the case of detecting the start of exposure, for example, when the signal value (pixel value) of the read image falls below a predetermined threshold value, it is determined that the exposure has ended.
Specifically, some evaluation value is calculated for the acquired image (signal value of the image) (step S23). The evaluation value may be any representative value such as the maximum value, the minimum value, the average value, the median value, and the mode value of the captured image.
Then, the control means 22 determines whether or not this evaluation value is below a predetermined threshold value (step S24).
In addition to the method of calculating the evaluation value from the image data (image signal value) for one frame, for example, the image signal value for one line is read out to calculate the evaluation value, and the exposure is terminated based on this. May be judged. Further, when a sensor for detecting the output of radiation is provided, the determination may be made by using the output of the radiation sensor or the like.

If the signal value of the image does not fall below the threshold value (step S24; NO), the counter is reset to "0" (step S25), the process returns to step S21, and the process is repeated.
On the other hand, when the signal value of the image is below the threshold value (step S24; YES), the exposure may have ended, so that the control means 22 “+1” the counter (step S26).
In this embodiment, the irradiation of radiation continues, and although the imaging should be continued, the imaging is erroneously terminated when the signal value temporarily drops due to some factor (disturbance influence). In order to prevent this, a so-called dead time is provided so that it is determined that the exposure is completed when the signal value continuously falls below the threshold value for a certain period of time.
Therefore, when the signal value of the image falls below the threshold value and the counter is advanced, the control means 22 further determines whether or not the counter exceeds a predetermined dead time (step S27).

If the counter does not exceed the predetermined dead time (step S27; NO), the process returns to step S21 and the process is repeated.
On the other hand, when the counter exceeds a predetermined dead time (step S27; YES), that is, when the signal value of the image continuously falls below the threshold value for a preset period, the exposure is terminated. A determination is made (step S28), and the image acquired during the dead time is deleted (destroyed) (step S29).

It is not essential to detect the end of the exposure, and for example, the imaging may be terminated when a predetermined time has elapsed from the start of the exposure.
When the end of exposure is detected and the imaging is terminated as in the present embodiment, the captured image acquired while the radiation is being irradiated can be appropriately discriminated, and the captured image is stored. When storing in the means 23 or the like or when transmitting the captured image data to an external device, only necessary images can be selected, and the amount of transmitted data and the amount stored in the memory are optimized.
It should be noted that even in the detection of the start of exposure, a certain dead time may be provided as in the case of detection of the end, and when the threshold value is continuously exceeded for a certain period of time, it may be determined that the exposure has started.
It should be noted that the threshold value of the image signal value (pixel value) and the dead time are appropriately set.

Here, the timing at which the end of radiation exposure is detected and the handling of images related to the boundary before and after the end of exposure will be described in detail with reference to FIGS. 10 and 11.
As in the example shown in FIG. 5, when the end of exposure is detected at the exact boundary between the set of charge accumulation and reading, the image in which the storage and reading are performed before the end of exposure is detected is displayed. It may be taken as a photographed image and the image after the end of exposure may be discarded. However, the end of exposure is not always detected at the boundaries of the set, as it was at the beginning of exposure.
As the detection timing, a case where the charge is being accumulated (when shown in FIG. 11) and a case where the reading operation is being performed (when shown in FIG. 10) are assumed. If the charge is being accumulated when the end of exposure is detected, and if the reading operation is in progress, it may be a problem whether or not to discard the image.

The following four patterns are assumed for handling in this case.
First, when the start of exposure is detected during the read operation and the end of exposure is also detected during the read operation, the start of exposure is detected when the nth line of a certain frame is read, and when the mth line is read. When the end of exposure is detected, if n> m, the frame becomes a partially unexposed image or a missing image, so the image read at the time of end detection is discarded.
Further, when n ≦ m, that is, when the timing of the start and the timing of the end of the exposure overlap, the read images up to the nth line are stored and the remaining part is discarded.
On the other hand, if the start of exposure is detected when the charge is accumulated and the end of exposure is detected during the read operation, the image at the time of end detection is discarded because there are only a few lines left. ..

Next, when the end of exposure is detected during charge accumulation, the signal value becomes large depending on the timing of charge accumulation when the end of exposure was detected, as in the case of exposure start detection. It is considered different.
Therefore, it is preferable to set a threshold value of the signal value in advance and determine whether to discard or store the image in relation to the threshold value.

In the case of moving image shooting, output fluctuation correction may be applied to the shot image in addition to offset correction. The output fluctuation correction is, so to speak, a gain correction in the frame direction (time axis direction).
In the graph shown in FIG. 12, time is taken on the horizontal axis and the output intensity of radiation is taken on the vertical axis.
When moving images are taken by continuously irradiating radiation, as shown in FIG. 12, the radiation output intensity may not always be constant during irradiation of radiation. This depends on the performance, characteristics, etc. of the radiation generator 60.
Therefore, in order to eliminate such variations in radiation output intensity, radiation output fluctuation information (dose fluctuation information) is stored in a storage means 23 as a correction information storage means, and is used for control as an image correction means. The means 22 corrects the data of the captured image.

The output fluctuation information may be acquired in parallel during shooting, or if the radiation generator 60 used for shooting is determined in advance, preliminary shooting is performed without arranging the subject M before shooting. Then, the one stored in advance may be used.
The output fluctuation information may be acquired by using an image signal, or, if a radiation sensor is mounted on the radiation imaging apparatus 1, the output signal of the sensor may be used. Further, a radiation sensor may be separately installed outside the radiation imaging apparatus 1 and this output signal may be used. Further, it may be obtained by combining some of these methods.
If the output fluctuation correction is performed before the offset correction, the output fluctuation correction affects the signal value of the noise component before the offset correction, and then the offset correction causes a deviation. Therefore, when performing output fluctuation correction, it is preferable to perform it after performing offset correction.

FIG. 13 is a flowchart showing a procedure in the case of performing output fluctuation correction.
When performing output fluctuation correction, for example, as shown in FIG. 13, first, a blank region (that is, a region in which a subject does not exist) is specified from the captured image (step S31). The method for specifying the blank area may be specified by the user, or the blank area may be determined from the feature amount of the acquired captured image.
Then, the signal value of the blank is acquired in all frames of the captured image (step S32), and this signal value is normalized by taking the average value of the signal values taken in all frames (step S33). ), Divide each frame of the captured image by the normalized signal value (step S34).

Although the case where the moving image is shot in the continuous shooting mode has been described so far, as shown in FIG. 3 and the like, in the present embodiment, it is also possible to shoot a still image in the still image shooting mode. There is.

FIG. 14 is a flowchart showing a procedure when a still image shooting mode is set and a still image is shot in the present embodiment.
As shown in FIG. 14, when shooting a still image, after performing the preparatory operation (step S41) before shooting, the TFT gate of the detection unit P in the radiographic image shooting device 1 is opened to output a signal value. Discard it as it is. That is, a reset operation is performed in which the opening and closing of the TFT gate is repeated in a short time (step S42).
The control means 22 determines at any time whether or not the radiation has been exposed (step S43), and if the exposure is not detected (step S43; NO), the reset operation of step S42 is repeated.
On the other hand, when exposure is detected (step S43; YES), the reset operation is stopped to shift to the charge accumulation state, and after accumulating for a predetermined time, the signal value is read out and the captured image is acquired (step S44). ). The acquired captured image (still image) is stored in the storage means 23 as the captured image storage means (step S45).
The charge accumulation operation in the still image shooting mode may be terminated after a time-out in a predetermined time, or may be performed until the end of exposure is detected as in the continuous shooting mode.

As the method for detecting the exposure, any method may be used as in the case of continuous photographing. For example, a radiation sensor for detecting radiation is provided inside or outside the radiation imaging apparatus 1, and the control means 22 is used. It may be detected by looking at the output of the radiation sensor. Further, in the still image shooting mode, for example, detection from a read signal value, use of a leak signal, etc., can be found in JP-A-2009-219538, International Publication No. 2011/135917, International Publication No. 2011/152093, etc. It can be detected by the various methods described.
By detecting the radiation in this way, even if the radiation imaging device 1 cannot synchronize (communicate) with the radiation generator 60, the reset operation is repeated at the moment when the radiation is exposed. , It becomes possible to take a still image by shifting to the charge accumulation state.

Further, after the exposure, an offset image is acquired (step S46) and stored in the storage means 23 as the correction information storage means (step S47).
Then, the offset correction is performed on the captured image using the offset image (step S48).
The timing of acquiring the offset image is not limited to after the exposure, but may be before the exposure, but in the case of still image shooting, the exposure time is extremely short compared to the case of continuous shooting. Since the amount of radiation in each shot is small, even if an offset image is acquired after exposure, the lag component on the offset image can be ignored.

Up to this point, the case where the radiation imaging device 1 is used in combination with the radiation generating device 60 that cannot be synchronized (communicated) has been described, but in the present embodiment, one radiation imaging device 1 is various. It is supposed to be used in combination with the radiation generator 60 of the above, and it is also possible to use it in combination with the radiation generator 60 capable of synchronizing (communication) with each other. The case where the radiation generator 60 and the radiation image pickup device 1 directly communicate with each other is not limited, and for example, the radiation generator 60 and the radiation image pickup device 1 can be synchronized via a console 50 or the like. It may be configured.
In this way, when the radiation imaging device 1 is used in combination with the communicable radiation generating device 60, the radiation imaging device 1 and the radiation generating device 60, or the radiation imaging device 1 and the radiation generating device 60 are used. The radiation imaging apparatus 1 and the radiation generator 60 cooperate with each other to capture a radiation image by a radiation imaging system including a console 50 that communicates with any of these.

FIG. 15 is a flowchart showing a procedure of a continuous imaging mode when the radiation imaging apparatus is used in combination with a radiation generating apparatus capable of synchronizing (communication) with each other.
As shown in FIG. 15, in this case, after performing the preparatory operation before shooting (step S51), the offset image is acquired (step S52), and the offset image is updated to a newly acquired one at any time to store the storage means. It is stored in 23 (step S53).
The control means 22 determines whether or not a ready signal for starting irradiation of radiation is received from the outside at any time (step S54), and if the signal for starting irradiation is not received (step S54; NO), returns to step S52. And repeat the acquisition of the offset image.
On the other hand, when the irradiation start signal is received (step S54; YES), the irradiation of radiation is permitted (step S55), this point is determined to be the timing of irradiation start, and the images acquired after that are used. It is acquired as a captured image (step S56) and stored in the storage means 23 (step S57).

The control means 22 determines at any time whether or not the irradiation of the radiation is completed (step S58), and if the irradiation is not completed (step S58; NO), returns to the step S56 and repeats the acquisition of the captured image. .. On the other hand, when the irradiation is completed (step S58; YES), the acquisition of the captured image is terminated, and the offset correction is performed on the captured image using the offset image (step S59).
The timing of offset correction is not limited to this, and may be before the determination of the end of radiation irradiation.

Further, when the radiation image photographing apparatus 1 is used in combination with the radiation generating apparatus 60 capable of synchronizing (communication), the pulse imaging mode can be selected in addition to the continuous imaging mode and the still image imaging mode. May be good. In this case, the operating means 31, which is a setting means for setting the shooting mode, is configured to be able to set the pulse shooting mode in addition to the continuous shooting mode and the still image shooting mode.
In the pulse imaging mode, a pulse generation unit (not shown) that generates a pulse of a synchronization signal is provided on the side that irradiates radiation (radiation generator 60) and the side that receives radiation (radiation imaging device 1), respectively, and this pulse generation A synchronous pulse is transmitted from the unit to the radiation generator 60 and the radiation imaging device 1.
In this case, the radiation image capturing device 1 and the radiation generating device 60 capture a moving image by accumulating / reading charges or irradiating radiation in synchronization with the synchronous pulse.
If the radiation image capturing device 1 can communicate with the radiation generating device 60 but cannot communicate with the pulse generating unit, it switches to the continuous photographing mode and performs imaging.

FIG. 16 is a flowchart showing a procedure when shooting is performed in the pulse shooting mode.
As shown in FIG. 16, in this case, after performing the preparatory operation before shooting (step S61), the offset image is acquired (step S62), and the offset image is updated to a newly acquired one at any time to store the storage means 23. Is stored in (step S63).
The control means 22 determines whether or not a ready signal (synchronous pulse) for starting irradiation of radiation has been received from the outside at any time (step S64), and if it does not receive the signal for starting irradiation (step S64; NO), The process returns to step S62 and the acquisition of the offset image is repeated.
On the other hand, when the irradiation start signal is received (step S66; YES), the irradiation of radiation is permitted (step S65), this point is determined to be the timing of irradiation start, and the images acquired after that are used. It is acquired as a captured image (step S66) and stored in the storage means 23 (step S67).

The control means 22 determines at any time whether or not the irradiation of the radiation is completed (step S68), and if the irradiation is not completed (step S68; NO), returns to the step S65 and permits the irradiation of the radiation. As it is, the acquisition of the captured image is repeated. On the other hand, when the irradiation is completed (step S68; YES), the acquisition of the captured image is terminated, and the offset correction is performed on the captured image using the offset image (step S69).
As in the case of the continuous shooting mode, the timing of offset correction may be before the determination of the end of radiation irradiation.

Further, when the radiation image capturing device 1 is used in combination with the radiation generating device 60 capable of synchronizing (communication), when shooting in the still image shooting mode, for example, the shooting is performed by the procedure shown in FIG. Will be done.
That is, in this case, as in the case shown in FIG. 14, a preparatory operation before shooting (step S71) is performed, and then a reset operation is performed (step S72).
The control means 22 determines whether or not a ready signal for starting irradiation of radiation has been received from the outside at any time (step S73), and if the signal for starting irradiation is not received (step S73; NO), resetting step S72. Repeat the operation.
On the other hand, when the irradiation start signal is received (step S73; YES), the reset operation is stopped to shift to the charge accumulation state, and after accumulating for a predetermined time, the signal value is read out and the captured image is acquired (step). S74). The acquired captured image (still image) is stored in the storage means 23 as the captured image storage means (step S75).
Further, after the exposure, an offset image is acquired (step S76) and stored in the storage means 23 as the correction information storage means (step S77).
Then, the offset correction is performed on the captured image using the offset image (step S78).

As described above, in the radiation imaging apparatus 1 of the present embodiment and the radiation imaging apparatus 100 including the same, the radiation imaging apparatus 1 is of course used in combination with the radiation generator 60 capable of synchronizing (communication). Even when used in combination with a radiation generator 60 that cannot communicate, the radiation exposure timing is appropriately detected, and an offset image is acquired in a state close to the captured image, such as immediately before the start of main imaging. be able to.
In addition, it can be used for various types of shooting such as continuous shooting and still image shooting, and the radiation image shooting device 1 can be widely utilized.

[effect]
As described above, the radiation imaging apparatus 1 in the present embodiment has a plurality of radiation detection elements arranged in a two-dimensional manner corresponding to each pixel of the image and generating a charge, and the plurality of radiation detection elements. Is a radiation image capturing device 1 that reads out the signal value of each pixel based on the generated charge and generates an image, and continuously outputs an image by repeating a charge accumulation operation and a reading operation at predetermined time intervals. A control means 22 that functions as a detection means for detecting the presence or absence of radiation exposure and a control means 22 as a detection means at a timing before detecting the radiation exposure. A storage means 23 as a correction information storage means for storing one or more acquired images as an offset image used for offset correction is provided.
As a result, even when the radiation imaging device 1 is used in combination with the radiation generator 60 that cannot be synchronized (communication), the timing of radiation exposure can be accurately grasped and acquired before the start of exposure. The image can be acquired as an offset image.
Therefore, it is possible to perform appropriate offset correction on the captured image regardless of the usage environment of the radiation image capturing apparatus 1.

Further, in the present embodiment, the storage means 23 as a captured image storage means and the storage means 23 for storing the image acquired at the timing after the control means 22 as the detection means detects the exposure of radiation as a captured image. A control means 22 as an image correction means for performing offset correction using an offset image with respect to the stored captured image is provided.
Therefore, the offset correction can be performed on the captured image by using the offset image acquired at an appropriate timing.

Further, in the present embodiment, the output fluctuation information is stored in the storage means 23 as the correction information storage means, and the control means 22 as the image correction means performs output fluctuation correction on the captured image using the output fluctuation information. You may.
In this case, a good captured image can be obtained even when the output of the radiation generator 60 varies.

Further, in the present embodiment, the detection means may also detect the end of radiation exposure, and in this case, the image acquired at the timing before the detection means detects the end of radiation exposure is referred to as a captured image. do.
Therefore, it is possible to prevent the image after the end of exposure from being saved as a captured image, and it is possible to reduce the memory capacity. Further, even when the data of the captured image is transmitted to an external device, it is possible to prevent unnecessary images from being transmitted as the captured image, so that the amount of data transfer can be suppressed.

Further, in the present embodiment, a notification means 32 including a display unit or the like is further provided as a first notification means for notifying the operation state related to shooting.
As a result, the user can know the operating state of the radiation imaging apparatus 1, and it is possible to prevent erroneous operation and the like.

Further, in the present embodiment, the notification means 32 functioning as the first notification means and the second notification means includes at least one of a display means, a voice output means, and a vibration generating means.
As a result, the user can easily know the state of the radiation imaging apparatus 1 and the types of imaging that can be performed.

Further, in the present embodiment, the control means 22 can implement a still image shooting mode in which images are generated one by one, in addition to the continuous shooting mode.
As a result, various captured images can be acquired by one radiographic image capturing device 1.

Further, in the present embodiment, the operation means 31 as a setting means for setting either the continuous shooting mode or the still image shooting mode is further provided, and the control means 22 performs a shooting operation according to the shooting mode set by the setting means. implement.
As a result, it is possible to perform various shootings with one radiation image capturing device 1, and it is possible to acquire various captured images.

Further, in the present embodiment, the control means 22 functions as a shooting mode determining means for determining a shooting mode that can be performed based on at least one of the remaining battery level and the remaining memory level.
The determination result is notified by the notification means 32 as the second notification means.
Therefore, the user can easily know the shooting mode that can be selected at present.

[Modification example]
Although the embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to such embodiments and can be variously modified without departing from the gist thereof.

For example, in the present embodiment, the control means 22 of the radiation image capturing device 1 in the radiation imaging system 100 controls the basic operation for image acquisition by the radiation image capturing device 1, and the radiation exposure by the radiation generating device 60. It also functions as a detection means for detecting the presence or absence of radiation, an image correction means for performing offset correction using an offset image on a shot image, a shooting mode judgment means for determining a feasible shooting mode, and radiation image shooting. An example is shown in which the device 1 alone can perform from acquisition of a captured image to various correction processes, but it is a detection means for detecting the presence or absence of radiation exposure by the radiation generator 60, and an offset image with respect to the captured image. The console 50 may also have a function as an image correction means for performing offset correction or the like using the above, a shooting mode determining means for determining a feasible shooting mode, and the like.

When the console 50 functions as a control device that performs various processes in place of the control means 22 of the radiographic image capturing device 1, the console 50 is an image storage means for storing an image acquired by using the radiographic image capturing device 1. And the detection information storage means that holds the detection information of the start of radiation exposure when the irradiation of the radiation to the radiation image capturing device 1 is started, and the image is the image based on the detection information stored in the detection information storage means. A discriminating means for determining whether the image is an offset image acquired at the timing before the exposure is detected or the captured image acquired at the timing after the radiation exposure is detected, and an offset with respect to the captured image. An image correction means for performing offset correction using an image is provided.
A specific configuration example in this case will be described with reference to FIG.

FIG. 18 is a main block diagram showing a main configuration of the console 50.
As shown in FIG. 18, the console 50 includes a control unit 51, a storage unit 52, an operation unit 53, a display unit 54, and a communication unit 55, and each unit is connected by a bus.

The control unit 51 is a control device composed of a CPU (Central Processing Unit), a RAM (Random Access Memory), and the like. The CPU of the control unit 51 reads out the system program and various processing programs stored in the storage unit 52 and expands them in the RAM in response to the operation of the operation unit 53, and executes various processes according to the expanded program.

The storage unit 52 is composed of a non-volatile semiconductor memory, a hard disk, or the like. The storage unit 52 stores data such as parameters or processing results required for processing by various programs and programs executed by the control unit 51. Various programs are stored in the form of a readable program code, and the control unit 51 sequentially executes an operation according to the program code.
Further, the storage unit 52, for example, replaces the storage means 23 of the above-mentioned radiation image capturing device 1, or together with the storage means 23, a correction information storage means for storing offset images, output fluctuation information, and the like, and a photographing image for storing captured images. It functions as an image storage means and the like. Further, the storage unit 52 may also function as a detection information storage means or the like for holding the detection information of the start of radiation exposure when the radiation imaging device 1 by the radiation generation device 6 is started to be irradiated with radiation. The captured image and the offset image are appropriately transmitted from the radiographic image capturing apparatus 1. Further, the output fluctuation information, the detection information, and the like may be transmitted from the radiographic image capturing device 1, or may be stored as being acquired by another external device and sent to the console 50.

The operation unit 53 includes a keyboard equipped with cursor keys, number input keys, various function keys, and a pointing device such as a mouse, and controls an instruction signal input by key operation on the keyboard or mouse operation. Output to 51. Further, the operation unit 53 may include a touch panel on the display screen of the display unit 54, and in this case, the instruction signal input via the touch panel is output to the control unit 51.
The operation unit 53 may function as a setting means for switching the shooting mode of the shooting performed by the radiation image shooting device 1 and setting one of the shooting modes.

The display unit 54 is composed of a monitor such as an LCD or a CRT, and displays input instructions, data, and the like from the operation unit 53 according to the instructions of the display signal input from the control unit 51.
The display unit 54 functions as a first notification means for notifying the operation state related to shooting, and a second notification means for notifying the user of the reason why the shooting mode cannot be performed when there is a shooting mode that can be performed or a shooting mode that cannot be performed. May be good.
By providing such a notification means, the user can know the operating state of the radiation image capturing apparatus 1, the feasible photographing mode, and the like, and it is possible to prevent erroneous operation and the like.
When the notification means is provided on the console 50, the function as the notification means is not limited to the display unit 54. A lamp, an indicator, or the like may be provided as a notification means, or an audio output means such as a speaker may be provided.
The first notification means and the second notification means may be the same or may be provided separately. A plurality of means such as a display unit 54 and a speaker may be provided as the notification means, and the user may be notified by a combination of a plurality of methods such as display and voice.
Further, when the console 50 is provided with the notification means, the radiation imaging apparatus 1 may not be provided with the notification means. Further, both the radiation imaging apparatus 1 and the console 50 may be provided with a notification means and may be appropriately combined to notify the user of various information.

The communication unit 55 includes a LAN adapter, a modem, a TA (Terminal Adapter), and the like, and controls data transmission / reception with each device connected to the communication network NT.

When the console 50 is configured to function as a control means and a control device in this way, when an image is acquired by the radiographic image capturing device 1, it is transferred to the console 50, and the transferred image is used as an image storage means. It is stored in the storage unit 52.
Further, the console 50 acquires the detection information of the start of radiation exposure at which the radiation imaging device 1 is started to be irradiated, and holds it in the storage unit 52 as the detection information storage means.
Then, based on the detection information stored in the storage unit 52, which is the detection information storage means, the image is an offset image acquired at the timing before detecting the radiation exposure, or the radiation exposure is detected. The control unit 51 determines whether the captured image is a captured image acquired at a later timing as a discriminating means, and performs offset correction on the captured image using an offset image as an image correction means. Information on various corrections such as output fluctuation correction may also be acquired, and these corrections may be performed on the console 50.

As described above, when the console 50 discriminates whether the image is a photographed image or an offset image, corrects various images, and the like, the burden on the control means 22 of the radiographic image photographing apparatus 1 can be reduced. Further, by appropriately transferring the image data or the like to the console 50, the memory capacity of the storage means 23 of the radiation image capturing apparatus 1 can be reduced, and the imaging can be performed without worrying about the memory capacity. Further, since the capacity of the storage unit 52 of the console 50 is larger than the memory capacity of the storage means 23, there is a margin in the memory capacity, and all the images obtained by continuous shooting are transferred to the console before the images are taken. It is also possible to determine whether the image is an image or an offset image, to correct the captured image, and the like, if necessary.
The control means 22 of the radiation imaging apparatus 1 and the console 50 may share roles and perform various processes. Also in this case, the load on the control means 22 and the storage means 23 of the radiographic image photographing apparatus 1 can be reduced, and smooth imaging can be performed.

In addition, the detailed configuration and detailed operation of each part constituting the radiation imaging apparatus 1 and the radiation imaging system 100 can be appropriately changed without departing from the spirit of the present invention.

1 Radiation imaging device 22 Control means 23 Storage means 31 Operation means 32 Notification means 50 Console 51 Control unit 52 Storage unit 53 Operation unit 54 Display unit 60 Radiation generator 100 Radiation imaging system

Claims (20)

It has a plurality of radiation detection elements that are arranged in a two-dimensional manner corresponding to each pixel of the image and generate a charge, and the signal value of each pixel is read out based on the charge generated by each of the plurality of radiation detection elements. It is a radiation imaging device that generates images.
A control means capable of carrying out a continuous shooting mode in which the image is continuously generated by repeating the charge accumulation operation and the read-out operation at predetermined time intervals.
A detection means that detects the presence or absence of radiation exposure,
A correction information storage means that stores one or more images acquired at a timing before the detection means detects radiation exposure as an offset image used for offset correction.
A radiographic imaging apparatus characterized by being equipped with. A captured image storage means that stores an image acquired at a timing after the detection means detects radiation exposure as a captured image, and a captured image storage means.
An image correction means for performing offset correction on the captured image stored in the captured image storage means using the offset image stored in the correction information storage means.
The radiographic imaging apparatus according to claim 1, further comprising. The correction information storage means further stores output fluctuation information and stores it.
The radiographic image photographing apparatus according to claim 2, wherein the image correction means corrects the captured image by using the output fluctuation information stored in the correction information storage means. The detection means also detects the end of radiation exposure.
The radiation imaging apparatus according to any one of claims 1 to 3, wherein an image acquired at a timing before the detection means detects the end of radiation exposure is used as a captured image. .. The radiographic imaging apparatus according to any one of claims 1 to 4, further comprising a first notifying means for notifying an operating state related to photographing. The radiographic imaging apparatus according to claim 5, wherein the first notifying means includes at least one of a display means, an audio output means, and a vibration generating means. The control means according to any one of claims 1 to 6, wherein the control means can also carry out a still image shooting mode in which the images are generated one by one in addition to the continuous shooting mode. Radiation imaging equipment. Further provided with a setting means for setting either the continuous shooting mode or the still image shooting mode.
The radiographic imaging apparatus according to claim 7, wherein the control means performs an imaging operation according to an imaging mode set by the setting means. A shooting mode determination means for determining a possible shooting mode based on at least one of the remaining battery level and the remaining memory level,
The radiographic imaging apparatus according to claim 7, further comprising a second notifying means for notifying the determination result by the photographing mode determining means. The radiographic imaging apparatus according to claim 9, wherein the second notifying means includes at least one of a display means, an audio output means, and a vibration generating means. It has a plurality of radiation detection elements that are arranged in a two-dimensional manner corresponding to each pixel of the image and generate a charge, and the signal value of each pixel is read out based on the charge generated by each of the plurality of radiation detection elements. It is a radiographic imaging system equipped with a radiographic imaging device that generates images and a console.
A control means capable of carrying out a continuous shooting mode in which the image is continuously generated by repeating the charge accumulation operation and the read-out operation at predetermined time intervals.
A detection means that detects the presence or absence of radiation exposure,
A correction information storage means that stores one or more images acquired at a timing before the detection means detects radiation exposure as an offset image used for offset correction.
A captured image storage means that stores an image acquired at a timing after the detection means detects radiation exposure as a captured image, and a captured image storage means.
An image correction means for performing offset correction on the captured image stored in the captured image storage means using the offset image stored in the correction information storage means.
A radiographic imaging system characterized by being equipped with. The radiographic imaging system according to claim 11, further comprising a first notification means for notifying an operating state related to photography. The radiographic imaging system according to claim 12, wherein the first notifying means includes at least one of a display means, an audio output means, and a vibration generating means. The method according to any one of claims 11 to 13, wherein the control means can also carry out a still image shooting mode in which the images are generated one by one in addition to the continuous shooting mode. Radiation imaging system. Further provided with a setting means for setting either the continuous shooting mode or the still image shooting mode.
The radiographic imaging system according to claim 14, wherein the control means performs an imaging operation according to an imaging mode set by the setting means. A shooting mode determination means for determining a possible shooting mode based on at least one of the remaining battery level and the remaining memory level,
The radiographic imaging system according to claim 14, further comprising a second notifying means for notifying the determination result by the photographing mode determining means. The radiographic imaging system according to claim 16, wherein the second notifying means includes at least one of a display means, an audio output means, and a vibration generating means. It is provided with a plurality of radiation detection elements that are arranged in a two-dimensional manner corresponding to each pixel of the image and generate a charge, and the signal value of each pixel is read out based on the charge generated by each of the plurality of radiation detection elements. It is a radiation imaging system including a radiation imaging device that generates an image, a console, and a radiation generator that irradiates radiation toward the radiation imaging device.
A control means capable of carrying out a continuous shooting mode in which the image is continuously generated by repeating the charge accumulation operation and the read-out operation at predetermined time intervals.
A detection means that detects the presence or absence of radiation exposure,
A correction information storage means that stores one or more images acquired at a timing before the detection means detects radiation exposure as an offset image used for offset correction.
A captured image storage means that stores an image acquired at a timing after the detection means detects radiation exposure as a captured image, and a captured image storage means.
An image correction means for performing offset correction on the captured image stored in the captured image storage means using the offset image stored in the correction information storage means.
A radiographic imaging system characterized by being equipped with. An image storage means for storing an image acquired by using a radiographic imaging device, and
A detection information storage means for holding the detection information of the start of radiation exposure to which the irradiation of radiation to the radiation imaging device is started, and the detection information storage means.
Based on the detection information stored in the detection information storage means, the image is an offset image acquired at the timing before the radiation exposure is detected, or is acquired at the timing after the radiation exposure is detected. A discriminating means for discriminating whether the image is a photographed image and
An image correction means for performing offset correction using the offset image on the captured image, and
A control device characterized by comprising. On the computer
An image storage function that saves images acquired using a radiation imaging device, and
A detection information storage function that retains the detection information of the start of radiation exposure when the radiation imaging device is started to be irradiated, and the detection information storage function.
Based on the detection information stored by the detection information storage function, the image is an offset image acquired at the timing before the radiation exposure is detected, or is acquired at the timing after the radiation exposure is detected. A discrimination function that determines whether the image was taken and
An image correction function that performs offset correction using the offset image on the captured image, and
A program characterized by realizing.

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