Radiography equipment

Abstract

To provide a radiography apparatus equipped with an effective area indicator that shows the effective area and a light-gathering field indicator that shows the light-gathering field area, which are identifiable. [Solution] The radiography apparatus includes an imaging unit having an effective region containing pixels that generate a radiographic image based on the irradiated radiation, and a light-gathering field region containing pixels that measure the radiation dose, and a control unit that outputs a signal for controlling radiation irradiation by comparing the measured dose with a threshold. An effective region indicator indicating the effective region and a light-gathering field indicator indicating the light-gathering field region are identifiablely provided on the radiation incident surface of the imaging unit.

Description

Technical Field

[0001] The present disclosure relates to a radiation imaging apparatus.

Background Art

[0002] In recent years, as a radiation imaging apparatus used for medical image diagnosis, the spread of an apparatus that acquires a digital image using a semiconductor sensor has been promoted. Also, in the field of radiation imaging apparatuses, a technique called automatic exposure control (AEC) (hereinafter referred to as the AEC function) is used to obtain an image with appropriate optical density and for dose management during imaging. This is a function of monitoring the irradiated radiation dose and controlling the irradiation of radiation when a specified threshold value is reached.

[0003] Patent Document 1 discloses a technique in which a pixel region for dose management and a pixel region for image generation are provided in an imaging unit, and by displaying the pixel region for dose management on the imaging unit, a user can easily align the subject and the imaging unit.

[0004] In the technique of Patent Document 1, since the light collection field can be changed according to the imaging site of the subject, when directly displaying the light collection field on the imaging unit main body, it may be necessary to display a plurality of light collection fields. Further, the display of the effective area and an index indicating the center of the effective area are also displayed together.

[0005] When taking a radiation image, first, the user aligns the subject according to the display of the light collection field. Then, guide light that illuminates the irradiation range with visible light is irradiated onto the imaging unit and the subject, and the irradiation range of the radiation is adjusted while comparing the ends and the center line of the guide light with the display of the effective area. In the alignment operation, since the user visually confirms the display of the effective area from the position of the radiation irradiation device, it may be difficult to distinguish between the display of the effective area and the display of the light collection field when the orientation or position of the radiation imaging apparatus is changed.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Publication No. 2018-50828 [Overview of the project] [Problems that the invention aims to solve]

[0007] This disclosure has been made in view of the above-mentioned problems and aims to provide a radiography apparatus in which an effective area indicator indicating the effective area and a light-gathering field indicator indicating the light-gathering field area are provided in an identifiable manner. [Means for solving the problem]

[0008] A radiographic apparatus according to one aspect of the present disclosure has the following configuration. That is, the radiographic apparatus according to the present disclosure is a radiographic apparatus having an imaging means having an effective region including pixels that generate a radiographic image based on irradiated radiation and a light-gathering field region including pixels that measure the dose of the radiation and a control means that outputs a signal for controlling the irradiation of the radiation by comparing the measured dose with a threshold, characterized in that an effective region indicator indicating the effective region and a light-gathering field indicator indicating the light-gathering field region are identifiablely provided on the radiation incident surface of the imaging means. [Effects of the Invention]

[0009] According to this disclosure, it becomes possible to provide a radiography apparatus in which an effective area index indicating an effective area and a light-gathering field index indicating a light-gathering field area are identifiable. [Brief explanation of the drawing]

[0010] [Figure 1] A block diagram showing the configuration of a radiography apparatus according to Embodiment 1. [Figure 2] A flowchart illustrating the processing flow of the radiography apparatus according to Embodiment 1. [Figure 3] A diagram illustrating the adjustment of the radiation exposure range during imaging. [Figure 4] A diagram showing an example of area indicators for a radiography apparatus according to Embodiment 1. [Figure 5] A diagram showing an example of area indicators for a radiography apparatus according to Embodiment 1. [Figure 6] A diagram showing an example of area indicators for a radiography apparatus according to Embodiment 1. [Figure 7] A figure showing an example of region indicators applied to the surface of a region indicator sheet member according to Embodiment 2. [Modes for carrying out the invention]

[0011] The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the invention to the claims. While multiple features are described in the embodiments, not all of these features are essential to the invention, and the features may be combined arbitrarily. Furthermore, in the attached drawings, the same or similar configurations are given the same reference numeral, and redundant descriptions are omitted. However, the dimensions and structural details shown in each embodiment are not limited to those shown in the text and drawings. In this specification, radiation includes not only X-rays, but also alpha rays, beta rays, gamma rays, particle beams, cosmic rays, etc.

[0012] [Embodiment 1] (Example of a radiography system configuration) Embodiment 1 describes an example of the configuration of a radiography apparatus that performs imaging using an imaging unit that displays a light-gathering field corresponding to the area to be imaged. Figure 1 is a diagram showing the configuration of the radiography apparatus in Embodiment 1. As shown in Figure 1, the radiography apparatus 100 has an imaging unit 101 with area indicators 104, a control PC 102 (control device), and a communication relay device 103. Separately from the radiography apparatus 100, a radiation generator 110 is provided as a radiation source. Here, the area indicators 104 include an effective area indicator 105 and a light-gathering field indicator 106.

[0013] The effective area index 105 is an index that indicates the pixel area (effective area) containing pixels that generate a radiation image based on the radiation irradiated onto the radiation incident surface of the imaging unit 101, and is an index that indicates the imaging range. The light-gathering field index 106 is a pixel area containing pixels that measure the radiation dose, and is an index that indicates the dose measurement area (light-gathering field area) corresponding to the imaging area (imaging area information). The effective area index 105 indicating the effective area and the light-gathering field index 106 indicating the light-gathering field area are identifiablely applied (drawn) on the radiation incident surface of the imaging unit 101. In this embodiment, the effective area index 105 and the light-gathering field index 106 are identifiablely applied (drawn) on the radiation incident surface by a method such as printing that can be visually confirmed.

[0014] The imaging unit 101 generates radiation image information based on the radiation signal emitted from the radiation generator 110 and subsequently passing through the subject. The imaging unit 101 also has a function to monitor the radiation dose emitted from the radiation generator 110.

[0015] The control PC 102 can receive imaging condition information from the user via the user interface (UI unit 209) and drive the imaging unit 101 based on the imaging condition information. The control PC 102 can also output the radiation image information received from the imaging unit 101 to a monitor or the like. Furthermore, the control PC 102 can control the imaging timing of the imaging unit 101 and the radiation irradiation timing from the radiation generator 110 via the communication relay device 103. The communication relay device 103 relays communication between the radiation generator 110 and the control PC 102.

[0016] The user can input shooting conditions through the UI unit 209 of the control PC 102, and can also instruct the radiation generator 110 to irradiate with radiation from the control panel provided on the radiation generator 110. The radiation generator 110 irradiates the subject and the imaging unit 101 with radiation when it receives an irradiation permission signal from the control PC 102 via the communication relay device 103.

[0017] In addition, the control PC 102 can control the radiation irradiation by comparing the measured dose with a threshold value, and the radiation generator 110 stops the radiation irradiation at the timing when it receives an irradiation stop signal from the control PC 102 via the communication relay device 103.

[0018] The imaging unit 101 includes an imaging panel 201, a drive control unit 204 that drives and controls the imaging panel 201, a region setting unit 205 that generates dose measurement region information and outputs it to the drive control unit 204, and a dose determination unit 206 that determines irradiation stop based on the dose information from the dose measurement pixels 202.

[0019] Here, in the imaging panel 201, each pixel including an imaging element that outputs a radiation signal corresponding to the irradiated radiation (incident light) is arranged in an array (a two-dimensional plane region). The photoelectric conversion element of each pixel converts the light converted by the phosphor into a radiation signal (charge) that is an electrical signal, and the capacitor of each pixel accumulates the radiation signal (charge). For example, as the phosphor of the imaging panel 201, CsI:Tl in which thallium (Tl) is added to cesium iodide (CsI) or a terbium-activated rare earth sulfide-based phosphor (for example, G2O2S:Tb) can be used. The imaging panel 201 has pixels (normal pixels 203) that generate a radiation image based on the radiation transmitted through the subject and pixels (dose measurement pixels 202) that measure the dose of radiation. The normal pixels 203 accumulate the radiation signal transmitted through the subject and generate a radiation image. The dose measurement pixels 202 periodically read out the radiation signal and monitor the irradiation dose. The output unit of the imaging panel 201 reads out and outputs signals from each pixel under the control of the drive control unit 204.

[0020] The normal pixel 203 outputs a radiation signal (radiation image information) to the image processing unit 208 of the control PC 102. The dose measurement pixel 202 outputs a radiation signal (dose information) to the dose determination unit 206. Here, the normal pixel 203 and the dose measurement pixel 202 each have different signal lines and gate lines, and the drive control unit 204 can drive the dose measurement pixel 202 and the normal pixel 203 at different timings. When a drive signal is supplied to each pixel from the drive control unit 204, the radiation signal (charge) converted by the photoelectric conversion element of each pixel is accumulated. Then, according to the signal from the drive control unit 204, information (radiation image information, dose information) based on the accumulated radiation signal (charge) is output from each pixel at different timings.

[0021] Regarding the pixel arrangement in the imaging panel 201, it is acceptable for the imaging panel 201, composed of multiple normal pixels 203, and the imaging panel 201, composed of multiple dose measurement pixels 202, to be arranged in a layered structure, or for the dose measurement pixels 202 and normal pixels 203 to be mixed and arranged on the same two-dimensional plane of the imaging panel 201. Furthermore, the normal pixels 203 and dose measurement pixels 202 may be arranged as separate pixels, or a single pixel may be divided into an area that functions as a normal pixel 203 and an area that functions as a dose measurement pixel 202.

[0022] The drive control unit 204 outputs a drive signal to the imaging panel 201, which is generated based on imaging condition information received from the control unit 207 in the control PC 102, thereby driving the imaging panel 201. The imaging condition information includes, for example, imaging area information (chest, abdomen, lumbar spine, etc.), imaging direction (PA (posterior-anterior) / AP (front-to-back), front / side), and subject information (body size, whether or not it is a child, etc.).

[0023] When imaging condition information is input from the control unit 207 to the drive control unit 204, the drive control unit 204 generates drive control signals for driving the pixels of the imaging panel 201 (dose measurement pixels 202 and normal pixels 203). The drive control unit 204 drives the normal pixels 203 to accumulate radiation signals from the start to the end of radiation irradiation, and then outputs the accumulated radiation signals.

[0024] The region setting unit 205 sets the pixel area (dose measurement area) to be used for dose measurement according to the imaging area information of the subject. Specifically, the region setting unit 205 receives imaging condition information from the control unit 207, selects dose measurement area information that has been set in advance for each imaging area based on this information, and outputs it to the drive control unit 204 and the control unit 207. The control unit 207 outputs the dose measurement area information obtained from the region setting unit 205 to the UI unit 209.

[0025] Based on the dose measurement area information acquired from the area setting unit 205, the drive control unit 204 identifies the pixel area of ​​the dose measurement pixels 202 used for dose measurement among the dose measurement pixels arranged on the imaging panel 201. Based on the drive control signal for the dose measurement pixels, the drive control unit 204 instructs the identified pixel area of ​​the dose measurement pixels 202 to perform dose monitoring drive, which involves periodic readout. The drive control unit 204 then drives and controls the dose measurement pixels 202 to periodically read out radiation signals from the pixels within the dose measurement area and output them to the dose determination unit 206.

[0026] The dose determination unit 206 receives the integrated dose value from the dose measurement pixels 202 and compares it with a preset dose threshold. If the integrated value exceeds the dose threshold, it outputs a radiation irradiation stop determination signal to the control unit 207 of the control PC 102. Based on the comparison result between the integrated dose value measured by the pixels in the pixel area and the preset threshold, the control PC 102 controls the system to stop radiation irradiation if the integrated value exceeds the threshold.

[0027] The control PC 102 includes a control unit 207, an image processing unit 208 that performs image processing on the radiation image, and a user interface (UI) unit 209. Here, the control unit 207 outputs the shooting condition information to the drive control unit 204 for the shooting unit 101 based on the shooting condition information input from the user via the UI unit 209.

[0028] Furthermore, the control unit 207 receives the drive status output from the drive control unit 204. After power is turned on to the imaging panel 201, the drive control unit 204 checks the output characteristics of the imaging panel 201 and performs preparatory driving of the imaging panel 201 until the output characteristics of the imaging panel 201 stabilize. Until the output characteristics of the imaging panel 201 stabilize, the drive control unit 204 transmits a drive status indicating that imaging is not possible to the control unit 207, and once the output characteristics of the imaging panel 201 stabilize, it transmits a drive status indicating that imaging is possible to the control unit 207. In addition, the control unit 207 communicates with the radiation generator 110 via the communication relay device 103 and transmits irradiation permission / stop signals.

[0029] The image processing unit 208 applies image processing such as offset correction, sensitivity correction, spatial frequency processing, gradation processing, and defect correction to the radiation image information received from the normal pixels 203 in the imaging unit 101.

[0030] The UI unit 209 receives the processed radiographic image output from the image processing unit 208 and outputs it to a display device such as a monitor, and can also transfer the image to a server of a hospital image management system such as a Picture Archiving and Communication Systems (PACS). The UI unit 209 can also output shooting condition information input by the user to the control unit 207. The control unit 207 acquires the dose measurement area information output by the area setting unit 205 and outputs it to the UI unit 209. The UI unit 209 receives the dose measurement area information from the control unit 207 and can display the dose measurement area based on the shooting site on an output device such as a monitor. For example, the UI unit 209 can function as a display control unit that controls the display of a display unit such as a monitor, and can output an image on an output device such as a monitor in which the dose measurement area information is superimposed on the image processed by the image processing unit 208. In other words, the UI unit 209 (display control unit) can display the image on the display unit in a display format in which the image processed and the dose measurement area set by the area setting unit 205 are superimposed. By performing this output control (display control), users can determine whether the dose measurement area is appropriately set for the area being photographed, based on the output (display) image. It is also possible to compare it with images previously taken under similar shooting conditions.

[0031] (Processing flow of the radiography device 100) Next, the processing flow of the radiography apparatus 100 according to Embodiment 1 will be explained using Figure 2. First, in step S201, power is turned on to the imaging unit 101. At the same time, power is also turned on to the imaging panel 201. The power of the control PC 102 must be on at this time. The drive control unit 204 starts a preparatory drive to start imaging based on the control unit 207. This preparatory drive controls the imaging unit 101, the control PC 102, and the communication relay device 103 so that radiography cannot be started until the output characteristics of the imaging panel 201 stabilize.

[0032] In step S202, the user selects an imaging protocol via the UI unit 209. An imaging protocol is an imaging application installed on the control PC 102, which is a dedicated imaging application for the radiography apparatus 100, prepared in advance for each imaging condition. The imaging protocol includes imaging condition information such as the imaging area, imaging direction (PA (rear-front) / AP (front-back), front / side), and subject information (body size, whether or not it is a child).

[0033] Next, the UI unit 209 outputs the shooting condition information to the drive control unit 204 and the area setting unit 205 via the control unit 207. When the shooting condition information, including the shooting area information, is input from the control unit 207 to the area setting unit 205, the area setting unit 205 selects the dose measurement area information corresponding to the shooting area information that has been stored in advance and outputs it to the drive control unit 204.

[0034] In step S203, the user aligns the subject's shooting area with the shooting unit 101. The user aligns the subject's shooting area with the light field index 106 corresponding to the shooting condition information selected in step S202.

[0035] Figure 3 illustrates the adjustment of the radiation irradiation range during imaging in Embodiment 1. Figure 3(a) schematically illustrates an example of radiation irradiation range adjustment, and the subject is omitted in the figure. Figure 3(b) illustrates the effective area indicator 105 and light field indicator 106 applied to the radiation incident surface 101a of the imaging unit 101. In the example of Figure 3(b), the light field indicator 106 is applied in a 3x3 arrangement, but the example is not limited to this, and various light field indicators 106 corresponding to the imaging area (imaging area information) may be applied. In addition, as an indicator for alignment, the radiation incident surface 101a of the imaging unit 101 is provided with a center line 107 that indicates the center position in the long side direction and the short side direction of the radiation incident surface 101a.

[0036] In step S204, the user aligns the radiation irradiation range from the radiation generator 110 with the effective area indicator 105 on the imaging unit 101, as shown in Figure 3. At this time, the radiation generator 110 emits guide light, which is visible light that illuminates the radiation irradiation range (Figure 3(a)), and the user can adjust the radiation irradiation range of the radiation generator 110 by aligning the ends of the guide light (G1~G4: Figure 3(a)) with the effective area indicator 105.

[0037] The user adjusts the irradiation range of the guide light by operating the radiation generator 110, and therefore visually confirms the effective area indicator 105 from a distance. On the other hand, the user uses the light-gathering field indicator 106 to align the subject with the imaging unit 101, and therefore visually confirms the light-gathering field indicator 106 from close range. For this reason, it is required that the radiation incident surface 101a of the imaging unit 101 be clearly marked with an effective area indicator 105 indicating the effective area and a light-gathering field indicator 106 indicating the light-gathering field area.

[0038] Figures 4, 5, and 6 show examples of area indicators (effective area indicator 105, light field indicator 106) in a radiography apparatus according to Embodiment 1.

[0039] As shown in Figure 4(a), for example, the effective area index 105 and the light field index 106 may be indicated on the radiation incident surface 101a by lines of different line widths. That is, by providing a difference in the thickness of the line indicating the effective area index 105 and the line indicating the light field index 106, it may be possible to distinguish between the effective area index 105 and the light field index 106.

[0040] As a specific example, the line thickness indicating the light field index 106 may be assigned with a first line width (e.g., 0.5 mm) or less, and the line thickness indicating the effective area index 105 may be assigned with a second line width (e.g., 1.0 mm) or more. Note that the numerical values ​​indicating the line width (line thickness) are illustrative examples, and the line thickness indicating the effective area index 105 may be assigned to the radiation incident surface 101a with a line width thicker than the line thickness indicating the light field index 106 (second line width > first line width).

[0041] Figure 4(b) shows an example in which rectangular (e.g., rectangular) light field indicators 106 are arranged in a matrix at different intervals in the vertical and horizontal directions. L1 indicates the horizontal spacing of the light field indicators 106, and L2 indicates the vertical spacing of the light field indicators 106. In Figure 4(a), the vertical and horizontal spacings are set to approximately equal intervals, whereas in Figure 4(b), the vertical and horizontal spacings are set to different intervals. As shown in Figure 4(b), by setting L1 and L2 to different spacings, it is possible to distinguish between the effective area indicator 105 and the light field indicator 106 by the difference in line width, and to easily select the optimal light field indicator 106 depending on, for example, the size of the subject or the area being photographed.

[0042] Furthermore, as shown in Figure 5, the color scheme of the radiation incident surface 101a of the imaging unit 101 (first color scheme), the color scheme of the line indicating the effective area indicator 105 (second color scheme), and the color scheme of the line indicating the light field indicator 106 (third color scheme) may be different color combinations. In particular, considering the visibility of the guide light, the first color scheme 501 (background color) of the radiation incident surface 101a may be white, the second color scheme 502 of the line indicating the effective area indicator 105 may be black, and the third color scheme 503 of the line indicating the light field indicator 106 may be gray.

[0043] Note that the color combinations shown are examples only, and it is possible to change the color combinations to make the effective area index 105 easier to distinguish from the light field index 106.

[0044] Furthermore, the effective area indicator 105 and the light field indicator 106 may be indicated on the radiation incident surface 101a by lines of different hues. That is, the effective area indicator 105 and the light field indicator 106 may be distinguished by providing a difference in the hues of the lines indicating each area.

[0045] Furthermore, the color characteristics are not limited to hue; they may also be lightness or saturation. By creating differences in the lightness and saturation of the lines indicating each region, it is possible to distinguish between the effective region indicator 105 and the light field indicator 106, and to change the color combination so that the effective region indicator 105 is easier to distinguish than the light field indicator 106. In other words, the effective region indicator 105 and the light field indicator 106 may be applied to the radiation incident surface 101a by lines with different lightness levels, or by lines with different saturation levels. As for the combination of color characteristics, the lines applied to the radiation incident surface 101a may differ in at least one of the characteristics of hue, lightness, and saturation.

[0046] Furthermore, as shown in Figure 6, the effective area index 105 and the light field index 106 may be applied to the radiation incident surface 101a using different line types. That is, the effective area index 105 and the light field index 106 may be distinguished by providing a difference in line type. Here, line types include solid lines, dashed lines, double lines, dashed lines, and double dashed lines. For example, as shown in Figure 6, the effective area index 105 may be applied with a solid line, and the light field index 106 may be applied with a dashed or double line.

[0047] Returning to Figure 2 for the explanation, in step S205, the user inputs the irradiation conditions on the control panel of the radiation generator 110, and then presses the irradiation button to start irradiating the subject and the imaging unit 101 with radiation. The control unit 207 obtains the drive status from the drive control unit 204 of the imaging unit 101 and confirms that the drive status indicates that imaging is possible. Upon receiving the drive status from the drive control unit 204 indicating that imaging is possible, the control unit 207 then instructs the drive control unit 204 to start driving to accumulate the radiation signal, and sends a radiation irradiation permission signal to the radiation generator 110 via the communication relay device 103 to permit radiation irradiation.

[0048] When imaging condition information is input from the control unit 207 to the drive control unit 204, the drive control unit 204 generates drive control signals for driving the pixels of the imaging panel 201 (dose measurement pixels 202 and normal pixels 203). Based on the drive control signal for the normal pixels, the drive control unit 204 instructs the normal pixels 203 to accumulate radiation signals.

[0049] Furthermore, the drive control unit 204 identifies the pixel area of ​​the pixels used for dose measurement based on the information indicating the dose measurement area set by the area setting unit 205 (dose measurement area information), and instructs dose monitoring drive to periodically read out based on the drive control signal for the pixels in the identified pixel area. In other words, the drive control unit 204 identifies the pixel area of ​​the dose measurement pixels 202 used for dose measurement among the dose measurement pixels arranged on the imaging panel 201 based on the dose measurement area information acquired from the area setting unit 205, and instructs dose monitoring drive to periodically read out based on the drive control signal for the dose measurement pixels for the identified pixel area of ​​the dose measurement pixels 202. The drive control unit 204 then drives and controls the dose measurement pixels 202 to periodically read out radiation signals from the pixels within the dose measurement area and output them to the dose determination unit 206. Through the drive control of the drive control unit 204, the dose measurement pixels 202 periodically output dose information to the dose determination unit 206.

[0050] In step S206, the dose determination unit 206 stores dose information periodically output from the dose measurement pixel 202 and compares the stored dose with a preset dose threshold (threshold) for each imaging area. If the stored dose is less than the dose threshold (S206-NO), the dose determination unit 206 continues the comparison process in step S206. On the other hand, if the stored dose becomes equal to or greater than the dose threshold, that is, if the stored dose matches the dose threshold (threshold) or exceeds the dose threshold (threshold) (S206-YES), the dose determination unit 206 outputs a determination to stop radiation irradiation to the control unit 207.

[0051] In step S207, when the control unit 207 receives an irradiation stop determination signal from the dose determination unit 206, it outputs a radiation irradiation stop signal to the radiation generator 110 via the communication relay device 103. The radiation generator 110 stops radiation irradiation as soon as it receives the radiation irradiation stop signal from the communication relay device 103. The control unit 207 also instructs the drive control unit 204 to stop the accumulation drive of the normal pixels 203 and stop the dose monitoring drive of the dose measurement pixels. After receiving the drive stop instruction from the control unit 207, the drive control unit 204 controls the system to stop the accumulation drive of the normal pixels 203 and stop the dose monitoring drive of the dose measurement pixels.

[0052] In step S208, the normal pixels 203 output radiation image information based on the accumulated radiation signal (charge) to the image processing unit 208 of the control PC 102. The image processing unit 208 performs image processing such as offset correction, sensitivity correction, spatial frequency processing, gradation processing, and defect correction on the acquired radiation image information and outputs the processed image to the UI unit 209. The control unit 207 acquires dose measurement area information from the area setting unit 205 and outputs it to the UI unit 209. The UI unit 209 functions as a display control unit and can output (display) the dose measurement area information acquired from the control unit 207 and the processed image to an output device such as a monitor in a superimposed display format. This allows the user to confirm the alignment result between the shooting area of ​​the subject and the dose measurement area. With the output of the dose measurement area information and the processed image to the output device by the control unit 207, the process moves to step S209 and the shooting is completed.

[0053] In the radiography apparatus 100 of this embodiment, an effective area index 105 indicating an effective area including pixels that generate a radiographic image, and a light-gathering field index 106 indicating a light-gathering field area including pixels that measure the radiation dose, are identifiable on the radiation incident surface of the imaging unit 101 based on the radiation irradiated onto the radiation incident surface. This allows the user to distinguish between the effective area index 105 and the light-gathering field index 106, and by checking the effective area index 105 and operating the radiation generator 110, the user can align the irradiation range of the guide light with the effective area index 105. In addition, the user can check the light-gathering field index 106 and align the subject with the imaging unit 101.

[0054] [Embodiment 2] Embodiment 2 describes a case in which the region indicator 104 (effective region indicator 105, light field indicator 106) is provided on the region indicator sheet member 114, and the region indicator sheet member 114 is attached to the radiation incident surface 101a of the imaging unit 101 for use. The region indicator sheet member 114 can be attached to the radiation incident surface 101a of the imaging unit 101, the effective region indicator 105 is provided on the region indicator sheet member 114 by drawing, and the light field indicator 106 is provided on the region indicator sheet member 114 by irregularities formed so as to be identifiable by at least one of sight and touch.

[0055] Figure 7(a) shows an example of area indicators (effective area indicator 105, light field indicator 106) applied to the surface of the area indicator sheet member 114 according to Embodiment 2, and Figure 7(b) is a diagram illustrating the configuration of the light field indicator 106 in the AA cross-section of Figure 7(a).

[0056] The region indicator sheet member 114 is transparent to the radiation emitted from the radiation generator 110 and is attached by being affixed to the radiation incident surface 101a of the imaging unit 101. The procedure for taking radiation images is the same as described in Embodiment 1, so the explanation will be omitted.

[0057] In this embodiment, the effective area indicator 105 is applied (drawn) on the surface of the area indicator sheet member 114 by a method such as printing that allows for visual confirmation. As for the method of application (drawing), as described in Embodiment 1, it may be applied to the radiation incident surface 101a by drawing lines. When drawing lines, for example, the line type or color characteristics (hue, brightness, saturation) may be changed in accordance with the imaging area information to apply (draw) the effective area indicator 105 on the surface of the area indicator sheet member 114. The user can check the effective area indicator 105 on the area indicator sheet member 114 and operate the radiation generator 110 to align the irradiation range of the guide light with the effective area indicator 105.

[0058] Furthermore, as shown in Figure 7(b), the light field indicator 106 has a structure in which braille-like indentations are formed on the surface of the area indicator sheet member 114, making it possible to identify the light field indicator 106 by at least one of sight and touch. Here, the indentations provided as the light field indicator 106 are not limited to a configuration in which indentations are formed at predetermined intervals, as shown in Figure 7(b), but the light field indicator 106 may also be provided by forming indentations in which the vertices of the indentations are connected in a linear manner. In addition, the light field indicator 106 may be provided on the surface of the area indicator sheet member 114 by indentations, or by recesses. For example, in correspondence with the imaging area information, the light field indicator 106 may be formed on the surface of the area indicator sheet member 114 by changing at least one pattern of indentations, indentations, and recesses (hereinafter also referred to as the indentation pattern).

[0059] As shown in Figure 7(b), by attaching (sticking) a textured area indicator sheet member 114, specifically a resin sheet with irregularities, to the radiation incident surface 101a of the imaging unit 101, the light field indicator 106 is provided on the radiation incident surface 101a by an irregular pattern formed to be identifiable by at least one of sight and touch. As a result, the effective area indicator 105 and the light field indicator 106, which indicates the light field area including the pixels for measuring the radiation dose, are identifiable on the radiation incident surface 101a. Furthermore, when aligning the subject, the user can check the light field indicator 106 to align the subject with the imaging unit 101.

[0060] In this embodiment, the region indicator sheet member 114 may be configured to make the light field indicator 106 easily identifiable by providing irregularities on the housing side of the imaging unit 101. That is, the effective region indicator 105 may be applied to the radiation incident surface 101a of the imaging unit 101 by a method such as printing that can be visually confirmed (for example, drawing), and the light field indicator 106 may be applied to the radiation incident surface 101a of the imaging unit 101 by an irregular pattern formed so as to be identifiable by at least one of sight and touch.

[0061] Furthermore, grids are sometimes used to suppress blurring of radiation images caused by scattered radiation when it passes through a subject. The region indicator sheet member 114 described in this embodiment may be attached to the surface of the grid. That is, the region indicator sheet member 114 can be attached to the surface of the grid, the effective region indicator 105 may be added to the region indicator sheet member 114 by drawing, and the light field indicator 106 may be added to the region indicator sheet member 114 by an uneven pattern formed so as to be distinguishable by at least one of sight and touch.

[0062] Alternatively, the region indicator sheet member 114 may be directly provided on the surface of the grid. For example, the effective region indicator 105 may be applied by drawing on the surface of a grid that can be attached to the radiation incident surface 101a of the imaging unit 101, and the light field indicator 106 may be applied to the surface of the grid by an uneven pattern formed so as to be identifiable by at least one of sight and touch.

[0063] According to this embodiment, a radiography apparatus can be provided that is identifiable by an effective area indicator showing the effective area and a light-gathering field indicator showing the light-gathering field area. The user can distinguish between the effective area indicator 105 and the light-gathering field indicator 106, and by checking the effective area indicator 105 and operating the radiation generator 110, the user can align the irradiation range of the guide light with the effective area indicator 105. In addition, the user can check the light-gathering field indicator 106 and align the subject with the imaging unit 101.

[0064] (Other embodiments) The present invention can also be realized by supplying a program that implements one or more of the functions of the above-described embodiments to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be realized by a circuit (e.g., an ASIC) that implements one or more functions.

[0065] The invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, claims are attached to disclose the scope of the invention. [Explanation of Symbols]

[0066] 101: Imaging unit, 102: Control PC (control device), 103: Communication relay device, 104: Area indicator, 105: Effective area indicator, 106: Light field indicator, 110: Radiation generator, 114: Area indicator sheet member, 201: Imaging panel, 202: Pixel for dose measurement, 203: Normal pixel, 204: Drive control unit, 205: Area setting unit, 206: Dose determination unit, 207: Control unit, 208: Image processing unit, 209: UI unit

Claims

[Claim 1] A radiography apparatus comprising: an imaging means having an effective region including pixels that generate a radiographic image based on irradiated radiation, and a light-gathering field region including pixels that measure the dose of the radiation; and a control means that outputs a signal for controlling the irradiation of the radiation by comparing the measured dose with a threshold, An effective area indicator indicating the effective area and a light-gathering field indicator indicating the light-gathering field area are provided on the radiation incident surface of the imaging means in a distinguishable manner. A radiography apparatus characterized by the following features.

Images