WO2019225388A1 - Radiography device, radiography system, radiography method, and program - Google Patents

Abstract

In this invention, an active pixel region, wherein a plurality of first pixels have been disposed in matrix form for the purpose of detecting the two-dimensional distribution of radiation and generating radiation image data, is provided with a second pixel, which is shielded from radiation, and an information processing device 103 monitors the pixel values contained in the output signals from the second pixel and displays the information indicated by the result.

Description

Radiographic apparatus, radiographic system, radiographic method, and program

The present invention relates to a radiation imaging apparatus, a radiation imaging system, a radiation imaging method, and a program, and is particularly suitable for use in imaging a subject using radiation.

As a radiographic apparatus used for medical image diagnosis and non-destructive inspection by radiation such as X-rays, a pixel array in which a plurality of pixels including switches such as TFTs (thin film transistors) and conversion elements such as photoelectric conversion elements are arranged in a matrix form A radiation imaging apparatus is put into practical use. In a radiography apparatus having a plurality of conversion elements such as photoelectric conversion elements, radiation is not performed at all for each pixel (zero irradiation) due to differences in the environment such as the temperature at which the apparatus is placed. There may be variations in the output (ie, offset output) values. In order to obtain good image quality, it is known to perform offset correction for correcting such pixel output variations.

As a first method for performing offset correction, every time main imaging with radiation is performed, imaging without radiation is performed, and an output difference between pixels corresponding to each other in the images obtained by the imaging is calculated. There is a method of performing offset correction. As a second method for performing offset correction, there is the following method. First, a plurality of images not irradiated with radiation are captured in advance before actual imaging, and an average value of the outputs of pixels corresponding to each other of the images obtained by the imaging is set as an offset image. Offset correction is performed by calculating a difference in output of pixels corresponding to each other between the offset image and the image obtained in the main photographing. In high-speed shooting such as moving image shooting, it is desirable to perform offset correction by the second method in order to suppress a decrease in frame rate. In addition, the second method has an advantage that noise is reduced because the offset image is created with a number of images as compared with the first method.

There is a technique described in Patent Document 1 regarding offset correction of the second method. Patent Document 1 discloses that, in addition to a photoelectric conversion element for acquiring a radiation signal in an effective pixel region, a light-shielded photoelectric conversion element for acquiring an offset signal is provided. In Patent Document 1, an output of a light-shielded photoelectric conversion element is used as an offset signal, and the offset signal is subtracted from the radiation signal.

Japanese Patent Laid-Open No. 2007-19820

However, in Patent Document 1, for example, if there is an extreme temperature distribution in the effective pixel region, and an artifact that exceeds the limit that can be corrected occurs, the artifact that exceeds the criteria required by the user will occur even if offset correction is performed. There is a possibility of occurring in a radiographic image.

An object of the present invention is for the user to grasp the state of the radiation imaging apparatus before imaging. The radiation imaging apparatus of the present invention shows an imaging unit having a plurality of second pixels that shield radiation, a monitoring unit that monitors the value of an output signal from the second pixel, and a result of monitoring by the monitoring unit. And display control means for displaying information on a display device.

According to the present invention, the user can grasp the state of the radiation imaging apparatus before imaging.

It is a figure which shows the structure of a radiography system. It is a figure which shows an effective pixel area | region. It is a figure which shows the structure of information processing apparatus. It is a flowchart which shows the 1st example of a process of a radiography system. It is a figure which shows an example of distribution of a pixel value. It is a figure which shows an example of distribution of a pixel value. It is a flowchart which shows the 2nd example of a process of a radiography system.

Hereinafter, embodiments will be described in detail with reference to the drawings. In each of the following embodiments, as a radiation imaging apparatus, an X using a flat panel display (also referred to as a flat panel detector) that captures X-ray image data of a subject using an X-ray that is a kind of radiation. A line imaging apparatus will be described as an example. The radiographic apparatus is not limited to the X-ray apparatus, and for example, radiographic apparatuses using other radiation (for example, α rays, β rays, γ rays, etc.) can be applied to the following embodiments. Is possible.

(First embodiment)
First, the first embodiment will be described. FIG. 1 is a diagram illustrating an example of the overall configuration of a radiation imaging system according to the present embodiment. The radiation imaging apparatus of this embodiment is used for human body imaging, for example.

In FIG. 1, an X-ray irradiation unit 101 irradiates a subject P with X-rays. The X-ray irradiation unit 101 includes an X-ray generation unit (tube) that generates X-rays and a collimator that defines a beam divergence angle of the X-rays generated in the X-ray generation unit. The radiation detection sensor 102 is an FPD (Flat Panel. Detector). The radiation detection sensor 102 includes an insulating substrate and a plurality of photoelectric conversion elements. The plurality of photoelectric conversion elements are arranged in a matrix on the insulating substrate.

FIG. 2 is a diagram illustrating an example of an effective pixel area in the radiation detection sensor 102. The arrangement of light shielding (OB (Optical Black)) pixels and the change in offset output will be described with reference to FIG. In FIG. 2, a plurality of photoelectric conversion elements are arranged in a matrix in the effective pixel region 200. Moreover, the shielding member which shields light with respect to the one part photoelectric conversion element of several photoelectric conversion elements is arrange | positioned. In FIG. 2, a pixel corresponding to the photoelectric conversion element in which the shielding member is arranged is shown as an optical shielding (OB) pixel 201. Note that, for convenience of description, in FIG. 2, one light shielding (OB) pixel is denoted by a symbol, but each point scattered in the effective pixel region 200 is light shielding (OB). ) Pixel. In FIG. 2, pixels other than the light shielding (OB) pixels (pixels corresponding to photoelectric conversion elements in which no shielding member is disposed) are disposed in a region 202 indicated by gray. In the present embodiment, for example, by using the radiation detection sensor 102, an example of an imaging unit having a light shielding pixel as a second pixel arranged in an effective pixel region where a plurality of first pixels are arranged is realized. In the present embodiment, for example, an example of a pixel (light shielding pixel) in which the radiation irradiated to the effective pixel region is shielded by the light shielding (OB) pixel.

In FIG. 2, the effective pixel region 200 changes from the state in the left diagram of FIG. 2 (the base end side of the white arrow line) to the state in the right diagram (the tip side of the white arrow line). A region where a pixel in which a change in offset output occurs is arranged is a region 203. The light shielding (OB) pixel 201 is not affected by an afterimage caused by X-rays. Focusing on this, the present inventors have found that the signal output from the light shielding (OB) pixel 201 is monitored as described later. By doing so, it is possible to evaluate a change in offset output caused by a change in temperature of the radiation detection sensor 102 or a change in imaging mode without being affected by an afterimage caused by X-rays.

Note that FIG. 2 shows an example in which the light shielding (OB) pixels 201 are uniformly arranged in the effective pixel region 200. However, the arrangement of the light shielding (OB) pixels 201 is not limited to that shown in FIG. For example, the light shielding (OB) pixels 201 may be arranged in a straight line, or may be arranged in a concentrated manner in a region where a change in offset output is expected. The number of pixels other than the light shielding (OB) pixels 201 is preferably larger than the number of light shielding (OB) pixels 201.

Returning to the description of FIG. 1, the radiation detection sensor 102 detects a two-dimensional distribution of X-rays reaching the photoelectric conversion element, and generates X-ray image data. The radiation detection sensor 102 transmits the generated X-ray image data to the information processing apparatus 103 (calculation unit 103c).

The photographing condition setting unit 103a has a user interface through which a user (operator) inputs photographing condition information indicating photographing conditions. The imaging condition information includes, for example, parameters such as a target dose of X-rays irradiated to the subject P, a tube voltage, a tube current, and an imaging mode of the radiation detection sensor 102. The shooting condition setting unit 103a transmits shooting condition information input by the user to the control unit 103b. The control unit 103b controls the X-ray irradiation unit 101 and the radiation detection sensor 102 based on the imaging condition information transmitted from the imaging condition setting unit 103a.

The calculation unit 103c generates X-ray image data suitable for diagnosis by performing correction processing such as offset correction based on the X-ray image data transmitted from the radiation detection sensor 102. The calculation unit 103c transmits the corrected X-ray image data to the display unit 103d. The display unit 103d outputs X-ray image data for display based on the X-ray image data received from the calculation unit 103c to a monitor or the like. In the present embodiment, for example, a radiation imaging apparatus is configured using the X-ray irradiation unit 101, the radiation detection sensor 102, and the information processing apparatus 103. Further, for example, a radiation imaging system is configured using the X-ray irradiation unit 101, the radiation detection sensor 102, the information processing apparatus 103, and a monitor.

FIG. 3 is a diagram illustrating an example of a hardware configuration of the information processing apparatus 103. The information processing apparatus 103 includes a CPU 301, a ROM 302, a RAM 303, an HDD 304, a display I / F unit 305, an input I / F unit 306, and a network I / F unit 307. The CPU 301 reads a control program stored in the ROM 302 and executes various processes. A RAM 303 is used as a temporary storage area such as a main memory and work area of the CPU 301. The HDD 304 stores various data, various programs, and the like. The display I / F unit 305 outputs data for displaying various information to a monitor or the like. The input I / F unit 306 has a keyboard and a mouse and accepts various operations by the user. The network I / F unit 307 performs communication processing with external devices such as the X-ray irradiation unit 101 and the radiation detection sensor 102 via the network. The network I / F unit 307 may communicate with an external device wirelessly.

Note that the functions and processing of the information processing apparatus 103 to be described later are realized by the CPU 301 reading a program stored in the ROM 302 or the HDD 304 and executing this program. As another example, the CPU 301 may read a program stored in a recording medium such as an SD card instead of the ROM 302 or the like.

In this embodiment, the information processing apparatus 103 is configured such that one processor (CPU 301) executes each process shown in a flowchart described later using one memory (ROM 302). It doesn't matter. For example, a plurality of processors, a plurality of RAMs, a ROM, and a storage can be cooperated to execute each process shown in a flowchart described later. Also, a part of processing may be executed using a hardware circuit. Moreover, it is good also as implement | achieving the function and process of the information processing apparatus 103 mentioned later using processors other than CPU. For example, a GPU (Graphics Processing Unit) may be used instead of the CPU.

Hereinafter, an example of processing from the start of shooting preparation of the subject P to shooting will be described with reference to the flowchart of FIG. In the present embodiment, an example of a method for detecting in advance a state in which shooting is performed that may cause the user to misdiagnose or feel uncomfortable with the diagnostic image will be described. In step S4100, the shooting condition setting unit 103a inputs shooting condition information based on the content of the user operation on the user interface. The imaging condition information includes, for example, parameters such as a target dose of X-rays irradiated to the subject P, a tube voltage, a tube current, and an imaging mode of the radiation detection sensor 102. The shooting condition setting unit 103a transmits shooting condition information to the control unit 103b. In this way, shooting conditions are set.

Next, in step S4101, the radiation detection sensor 102 acquires a fixed dark image. The fixed dark image is an image taken by the radiation detection sensor 102 in a state where X-rays are not irradiated based on parameters other than the parameters related to X-ray irradiation among the parameters set in step S4100. Here, even if the subject P exists, the subject P may not exist. The fixed dark image is an image used for fixed dark (offset correction). The radiation detection sensor 102 acquires the output signal from the light shielding (OB) pixel among the output signals from the pixels of the fixed dark image, and transmits them to the calculation unit 103c.

Here, the case where the output signal from the light shielding (OB) pixel is acquired from the fixed dark image has been described as an example. However, it is not always necessary to acquire the output signal from the light shielding (OB) pixel in this way as long as it is acquired from an image captured by the radiation detection sensor 102 in a state where X-rays are not irradiated. For example, the radiation detection sensor 102 may acquire an output signal from the light shielding (OB) pixel from a dark image captured at a timing close to the fixed dark image in time.

Next, in step S4102, upon receiving an output signal from the light shielding (OB) pixel, the calculation unit 103c records information on the output signal from the light shielding (OB) pixel. Next, in step S4103, the radiation detection sensor 102 acquires a dark image, acquires an output signal from a light shielding (OB) pixel among output signals from the pixel of the dark image, and transmits the output signal to the calculation unit 103c. . Here, as in step S4101, the subject P may be present or the subject P may not be present. The process of step S4103 is realized by performing the same process as step S4101. That is, the radiation detection sensor 102 acquires an output signal from the light shielding (OB) pixel in each of step S4101 and step S4103 (at different timings).

Next, in step S4104, the calculation unit 103c uses the output signal information from the light shielding (OB) pixel recorded in step S4102 and the output signal information from the light shielding (OB) pixel acquired in step S4103. Compare. Based on the result of the comparison, the calculation unit 103c determines whether shading (density unevenness) or the like that leads to an impediment to diagnosis or a sense of discomfort has occurred. Then, the calculation unit 103c transmits information indicating the result of the determination to the display unit 103d. The display unit 103d displays information indicating the determination result on a monitor or the like. The user determines whether to perform X-ray imaging by viewing this information.

In the present embodiment, for example, an example of a monitoring unit that monitors the value of the output signal from the light shielding pixel is realized by using the arithmetic unit 103c. In the present embodiment, for example, an example is realized in which the calculation unit 103c performs comparison in step S4104 to monitor the value of the output signal from the light shielding pixel obtained at a plurality of different timings. Is done. Further, the light shielding pixel obtained in a state where the effective pixel region is not irradiated with radiation at each of the plurality of different timings based on the output signal from the light shielding (OB) pixel acquired in steps S4101 and S4103. An example of an output signal from is realized. Moreover, in this embodiment, an example of the display control means which displays the information which shows the monitoring result by the said monitoring means on a display apparatus by using the calculating part 103c, for example is implement | achieved.

Next, in step S4105, the imaging condition setting unit 103a transmits operation information indicating whether or not there is an instruction for X-ray imaging to the control unit 103b based on the content of the operation on the user interface by the user. The controller 103b determines whether or not to perform X-ray imaging of the subject P based on the operation information. As a result of this determination, when X-ray imaging is not performed, the process proceeds to step S4103. On the other hand, when performing X-ray imaging, the control unit 103b instructs the X-ray irradiation unit 101 to perform X-ray imaging of the subject P based on the imaging conditions set in step S4100. Thereby, the X-ray image of the subject P is taken by the radiation detection sensor 102. In the present embodiment, for example, by using the control unit 103b, after the information indicating the monitoring result by the monitoring unit is displayed on the display device by the display control unit, imaging for instructing the radiographing of the subject is performed. An example of the control means is realized.

Hereinafter, an example of the determination method in step S4104 will be described with reference to FIGS. 5 and 6. As described above, the calculation unit 103c uses the output signal from the light shielding (OB) pixel acquired at the same time as the acquisition of the fixed dark image recorded in step S4102, and the light shielding (OB) pixel acquired in step S4103. Compare the output signals of. Due to the passage of time, changes in imaging mode, etc., when the temperature of the radiation detection sensor 102 changes due to the heat generating member in the radiation detection sensor 102, the offset output changes and shading occurs. The calculation unit 103c compares output signals from the light shielding (OB) pixels in order to determine whether or not this shading has occurred.

FIG. 5 shows an example of the distribution of pixel values based on the output signal from the light shielding (OB) pixel recorded in step S4102, and the distribution of pixel values based on the output signal from the light shielding (OB) pixel acquired in step S4103. FIG. FIG. 5 shows a distribution of pixel values when a change in offset output occurs due to a temperature change of the radiation detection sensor 102 between the timings of steps S4102 and S4103.

In FIG. 5, a pixel value distribution 501 indicates a distribution of pixel values included in an output signal from the light shielding (OB) pixel recorded in step S4102. A pixel value distribution 502 indicates a distribution of pixel values included in the output signal from the light shielding (OB) pixel acquired in step S4103. In step S4104, the calculation unit 103c may determine whether or not the absolute value of the difference between the mode values of the pixel value distributions 501 and 502 exceeds a threshold value. Further, the calculation unit 103c may determine whether or not the absolute value of the difference between the standard deviations of the pixel value distributions 501 and 502 exceeds a threshold value. For example, when the absolute value of the difference between the mode value and the standard deviation of the pixel value distributions 501 and 502 exceeds the threshold value, the calculation unit 103c determines that shading occurs, and otherwise determines that no shading occurs. Then, the calculation unit 103c transmits information indicating the result of the determination to the display unit 103d. In the present embodiment, for example, the light shielding pixel obtained at a plurality of different timings by determining whether or not the absolute value of the difference between the mode values of the pixel value distributions 501 and 502 exceeds a threshold value. An example of comparing the distribution of the value of the output signal from is realized.

FIG. 6 shows the pixel value included in the output signal from the light shielding (OB) pixel recorded in step S4102, and the pixel value included in the output signal from the light shielding (OB) pixel acquired in step S4103. It is a figure which shows an example of the distribution of the difference for every same coordinate (pixel). 6 also shows the distribution of pixel values when a change in offset output occurs due to a temperature change in the radiation detection sensor 102 between the timings of steps S4102 and S4103, as in FIG.

As illustrated in FIG. 6, the calculation unit 103 c may determine whether or not the absolute value of the difference between pixel values for one or more identical coordinates exceeds a threshold value (see a circle indicated by a broken line in FIG. 6). . For example, when the absolute value of the difference between the pixel values of one or more identical coordinates exceeds the threshold, the calculation unit 103c determines that shading occurs, otherwise determines that no shading occurs, and Information indicating the result is transmitted to the display unit 103d. In the present embodiment, for example, such a determination realizes an example of comparing a threshold value with a difference between values of output signals from the light shielding pixels obtained at a plurality of different timings.

Also, the representative value of the pixel value included in the output signal from the light shielding (OB) pixel recorded in step S4102, and the pixel value included in the output signal from the light shielding (OB) pixel acquired in step S4103. It may be determined whether the absolute value of the difference from the representative value exceeds a threshold value. As the representative value, for example, an average value, a median value, or a mode value can be adopted. In the present embodiment, for example, such a determination realizes an example of comparing a threshold value with a difference between representative values of output signals from the light shielding pixels obtained at a plurality of different timings. .

5 and 6, the pixel value included in the output signal from the light shielding (OB) pixel recorded in step S4102, and the output signal from the light shielding (OB) pixel acquired in step S4103. The case where the pixel value is compared is described as an example. However, it is not always necessary to compare pixel values included in output signals from light-shielded (OB) pixels obtained at different timings. It is also possible to monitor the value of the output signal from the light shielding (OB) pixel obtained at the same timing. For example, the computing unit 103c may determine whether or not the standard deviation of at least one of the pixel value distributions 501 and 502 exceeds a threshold value. In the present embodiment, for example, such a determination realizes an example of comparing a representative value of a value of an output signal from the plurality of light shielding pixels obtained at the same timing with a reference value. Further, at least one of the pixel value included in the output signal from the light shielding (OB) pixel recorded in step S4102 and the pixel value included in the output signal from the light shielding (OB) pixel acquired in step S4103. It may be determined whether one exceeds a threshold value. In the present embodiment, for example, such a determination realizes an example of comparing a value of an output signal from at least one light shielding pixel among the plurality of light shielding pixels with a threshold value. Further, the presence / absence of shading may be determined by combining the plurality of determination methods described above.

Also, it is assumed that a desired output signal cannot be obtained from the light shielding (OB) pixel due to the noise component. Therefore, in order to exclude the influence of noise components, the calculation unit 103c may be configured as follows. First, the calculation unit 103c compares the output signal from the target light shielding (OB) pixel with the output signal from one or more light shielding (OB) pixels adjacent to the target light shielding (OB) pixel. . Then, when the absolute value of the difference between the pixel values included in the output signals of both exceeds the threshold value, the calculation unit 103c uses the target light shielding (OB) pixel as the light shielding (OB) pixel used for the above-described determination. Exclude from

Next, an example of the determination result display in step S4104 will be described.

The display unit 103d displays information indicating whether the radiation detection sensor 102 is not suitable for X-ray imaging on a monitor or the like. Based on this display, the user determines whether or not to perform X-ray imaging. Further, it may be limited so that the control unit 103b that has received from the calculation unit 103c that the radiation detection sensor 102 is not suitable for X-ray imaging cannot perform X-ray imaging. At this time, information indicating that the state is not suitable for X-ray imaging may be displayed by the display unit 103d, but may not be displayed. For example, the radiation detection sensor 102 is suitable for X-ray imaging even if the user does not indicate that the X-ray imaging is not performed even if an instruction for X-ray imaging is performed, and thus does not indicate that the state is not suitable for X-ray imaging. It is possible to grasp that there is no state. The control unit 103b may release the restriction after waiting for the radiation detection sensor 102 to return from a state unsuitable for X-ray imaging based on the result of the determination described above. If the state is not suitable for X-ray imaging, the display unit 103d may not display that the state is not suitable for X-ray imaging.

As described above, in this embodiment, the information processing apparatus 103 monitors the pixel value included in the output signal from the light shielding (OB) pixel and displays information indicating the result. Therefore, it becomes possible for the user to grasp the state of the radiation imaging apparatus before imaging. In addition, the user knows in advance that an X-ray image that may cause a misdiagnosis of the subject (person) of the X-ray image or an uncomfortable X-ray image is taken. It becomes possible to make it.

(Second Embodiment)
Next, a second embodiment will be described. In the first embodiment, the case where it is determined whether or not the radiation detection sensor 102 is in a state suitable for X-ray imaging without performing X-ray imaging has been described as an example. In contrast, in the present embodiment, a case will be described in which it is determined whether or not the radiation detection sensor 102 is in a state suitable for X-ray imaging after performing X-ray imaging. As described above, the present embodiment is obtained by adding processing for performing X-ray imaging when determining whether or not the state is suitable for X-ray imaging to the first embodiment. Therefore, in the description of the present embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals as those in FIGS. 1 to 6, and detailed description thereof is omitted.

The configuration of the radiation imaging system of the present embodiment can be realized with the same configuration as that shown in FIGS. A part of the processing (flowchart in FIG. 4) in the radiation imaging system is different from that in the first embodiment. Hereinafter, an example of processing from the start of shooting preparation of the subject P to shooting will be described with reference to the flowchart of FIG.

The processing from step S7100 to step S7102 is the same as the processing from step S4100 to step S4102 described in the first embodiment. Prior to step S7103, the processing from step S4103 to step S4105 described in the first embodiment may be performed.

In step S7103, the control unit 103b instructs the X-ray irradiation unit 101 to perform X-ray imaging based on the imaging conditions set in step S7100. As a result, an X-ray image is taken by the radiation imaging apparatus 102. Next, in step S7104, the radiation detection sensor 102 acquires an output signal from each pixel of the X-ray image and transmits the output signal to the calculation unit 103c. Further, the radiation detection sensor 102 acquires an output signal from the light shielding (OB) pixel among the output signals from the pixel of the X-ray image, and transmits the output signal to the calculation unit 103c. In the present embodiment, for example, an example of an output signal from the light shielding pixel obtained in a state where the effective pixel region is irradiated with radiation based on an output signal from the light shielding (OB) pixel acquired in step S7104. Is realized.

Next, in step S7105, the operation unit 103c performs correction processing on the X-ray image data, and transmits the X-ray image data subjected to the correction processing to the display unit 103d. The display unit 103d displays an X-ray image based on the X-ray image data transmitted from the calculation unit 103c. Next, in step S7106, the calculation unit 103c uses the output signal information from the light shielding (OB) pixel recorded in step S7102 and the output signal information from the light shielding (OB) pixel acquired in step S7104. Compare. Based on the result of the comparison, the calculation unit 103c determines whether or not shading or the like that hinders diagnosis or causes discomfort occurs. The calculation unit 103c transmits information indicating the result of the determination to the display unit 103d. The display unit 103d displays information indicating the determination result on a monitor or the like.

In the present embodiment, for example, an example of a monitoring unit that monitors the value of the output signal from the light shielding pixel is realized by using the arithmetic unit 103c. In the present embodiment, for example, an example is realized in which the calculation unit 103c performs comparison in step S7106 to monitor the value of the output signal from the light shielding pixel obtained at a plurality of different timings. Is done. Moreover, in this embodiment, an example of the display control means which displays the information which shows the monitoring result by the said monitoring means on a display apparatus by using the calculating part 103c, for example is implement | achieved.

Next, in step S7107, the imaging condition setting unit 103a transmits, to the control unit 103b, operation information indicating whether or not there is an X-ray imaging instruction based on the content of the operation on the user interface by the user. The controller 103b determines whether or not to perform X-ray imaging of the subject P based on the operation information. If the result of this determination is that X-ray imaging is not performed, imaging is terminated. On the other hand, when performing X-ray imaging, the process returns to step S7103 described above. If it is determined in step S7107 that X-ray imaging is not performed, the processing in steps S4101 to S4105 in FIG. 4 may be performed. In the present embodiment, for example, by using the control unit 103b, after the information indicating the result of monitoring by the monitoring unit is displayed on the display device by the display control unit, imaging for instructing to capture a radiographic image of the subject An example of the control means is realized.

The determination method in step S7106 and the display contents of the determination result are the same as those in step S4104 described in the first embodiment. Also in this embodiment, various determination methods and display methods described in the first embodiment can be employed. Even if it does as mentioned above, the same effect as a 1st embodiment is acquired. In the first embodiment and the second embodiment, the pixel value included in the output signal from the light shielding (OB) pixel in the effective pixel region is monitored, and information indicating the result is displayed as an example. And explained. However, this is not always necessary. That is, the pixel value included in the output signal from the light shielding (OB) pixel outside the effective pixel region may be monitored, and information indicating the result may be displayed.

It should be noted that each of the above-described embodiments is merely a specific example for carrying out the present invention, and the technical scope of the present invention should not be construed in a limited manner. . That is, the present invention can be implemented in various forms without departing from the technical idea or the main features thereof.

(Other embodiments)
The present invention supplies a program that realizes one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in a computer of the system or apparatus read and execute the program This process can be realized. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.
Other embodiments

Embodiment (s) of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (eg, one or more programs) recorded on a storage medium (which refer to as a 'non-transitory computer-readable storage medium') to perform the functions of one or more of the above-described embodiment (s) and / or that includes one or more circuits (eg, application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment (s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from to the functions of one or more of the above-described embodiment (s) and / or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment (s). The computer may comprise one or more processors (eg, central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium example include, hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu- ray (registered trademark) Disc (BD)), a flash memory device, a memory card, and the like.

The present invention is not limited to the above embodiment, and various changes and modifications can be made without departing from the spirit and scope of the present invention. Therefore, in order to make the scope of the present invention public, the following claims are attached.

This application claims priority on the basis of Japanese Patent Application No. 2018-100573 filed on May 25, 2018, the entire contents of which are incorporated herein by reference.

Claims (15)

An imaging unit having a plurality of second pixels that shield radiation in an effective pixel region in which a plurality of first pixels are arranged in a matrix to detect a two-dimensional distribution of radiation and generate radiation image data;
Monitoring means for monitoring values of output signals from the plurality of second pixels;
A radiation imaging apparatus comprising: display control means for displaying information indicating a result of monitoring by the monitoring means on a display device. The radiation imaging apparatus according to claim 1, wherein the second pixel is a pixel that shields radiation applied to the effective pixel region. The imaging control means for instructing imaging of a radiographic image of a subject after the information indicating the result of monitoring by the monitoring means is displayed on the display device by the display control means. The radiation imaging apparatus described in 1. The radiographic apparatus according to any one of claims 1 to 3, wherein the monitoring means monitors the value of an output signal from the second pixel obtained at a plurality of different timings. The output signal from the second pixel obtained at a plurality of timings different from each other is the output signal from the second pixel obtained without being irradiated with the radiation at each of the plurality of timings different from each other. The radiation imaging apparatus according to claim 4, comprising: The output signal from the second pixel obtained at a plurality of different timings includes an output signal from the second pixel obtained in a state where the radiation is irradiated. Or the radiography apparatus of 5. The monitoring unit is configured to output a difference between values of the output signals from the second pixels obtained at a plurality of different timings or output signals from the second pixels obtained at a plurality of different timings. 7. The radiation imaging apparatus according to claim 4, wherein a difference between the representative values of the first and second threshold values is compared with a threshold value. The radiation according to any one of claims 4 to 6, wherein the monitoring unit compares distributions of values of output signals from the second pixels obtained at a plurality of different timings. Shooting device. The radiation imaging apparatus according to any one of claims 1 to 3, wherein the monitoring unit monitors values of output signals from the plurality of second pixels obtained at the same timing. 10. The radiation imaging apparatus according to claim 9, wherein the monitoring unit compares a representative value of a value of an output signal from the plurality of second pixels obtained at the same timing with a reference value. 4. The monitoring unit according to claim 1, wherein the monitoring unit compares a value of an output signal from at least one second pixel of the plurality of second pixels with a threshold value. Radiography equipment. 12. The radiation imaging apparatus according to claim 1, wherein the monitoring unit monitors whether or not shading has occurred in the effective pixel region. An imaging unit having a plurality of second pixels that shield radiation in an effective pixel region in which a plurality of first pixels are arranged in a matrix to detect a two-dimensional distribution of radiation and generate radiation image data;
Monitoring means for monitoring values of output signals from the plurality of second pixels;
A radiation imaging system comprising: display means for displaying information indicating a result of monitoring by the monitoring means. In order to detect a two-dimensional distribution of radiation and generate radiation image data, an imaging unit having a plurality of second pixels that shield radiation in an effective pixel region in which a plurality of first pixels are arranged in a matrix is used. Radiography method
A monitoring step of monitoring a value of an output signal from the second pixel;
A radiographic imaging method comprising: a display control step of displaying information indicating a result of monitoring by the monitoring step on a display device. A program that causes a computer to function as each means of the radiation imaging apparatus according to any one of claims 1 to 12.

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