Radiography system

Abstract

The present invention relates to a radiography system and, more specifically, to a radiography system capable of implementing, when a patient and the like is treated using radiation, an automatic exposure control (AEC) function even if various delays occur when an AEC signal is transmitted and received during radiation emission.

Description

Radiography system

[0001] The present invention relates to a radiographic system. More specifically, the present invention relates to a radiographic system capable of implementing an Automatic Exposure Control (AEC) function even when various delays occur when transmitting and receiving AEC signals during radiation irradiation when treating a patient or the like using radiation.

[0002] Radiography plays a crucial role in protecting the human body from disease and advancing medicine, and is an essential part of virtually all medical imaging examinations. Furthermore, recent scientific advancements and the shift to digital imaging devices are rapidly changing the radiation exposure environment.

[0003] While these digital medical environments offer the advantage of maximizing user convenience, reducing detector image noise and improving image quality can increase patient exposure. Thus, medical radiation exposure accounts for the largest proportion of man-made radiation exposure. Consequently, recent interest has focused on medical exposure management—methods for minimizing radiation exposure while maximizing diagnostic information.

[0004] Meanwhile, examinations using diagnostic radiation must be performed under appropriate conditions and with an appropriate dose. This requires understanding the subject's radiation absorption level. However, in reality, directly assessing the subject's condition is difficult. Therefore, control devices utilizing Automatic Exposure Control (AEC) are widely used to automatically deliver the appropriate radiation dose required for the image density.

[0005] In the case of a conventional radiographic system, two types of delay may exist when transmitting an AEC signal from a radiation detector to a radiation irradiation device.

[0006] First, there may be internal delays within the control unit, such as the CPU, required to process various commands and recognize AEC conditions to implement AEC functions. Second, there may be communication delays when transmitting AEC signals from the radiation detector to the radiation irradiator (e.g., wirelessly).

[0007] If the aforementioned delay occurs, the AEC function may not be properly implemented, which may result in patients, etc. being exposed to more radiation than necessary, thus increasing their radiation dose.

[0008] The present invention aims to solve the above-described problems by providing a radiographic system capable of implementing automatic exposure control (AEC) by transmitting an AEC signal based on the pixel value of a pixel unit of a radiation detector.

[0009] In particular, the present invention aims to provide a radiographic system capable of accurately implementing automatic exposure control (AEC) even when a data transmission delay occurs in wireless communication when wirelessly transmitting an AEC signal from a radiation detector to a radiation irradiation device.

[0010] The present invention provides a radiographic imaging system comprising: a radiation irradiation device having a radiation generator that generates radiation and a radiation control unit that controls the radiation generator; a detector that generates an image of a subject (S) by radiation that has passed through the subject and generates an AEC signal; and an integrated control unit that wirelessly receives the AEC signal and transmits it to the radiation control unit, wherein the detector charges a plurality of pixel units with charges proportional to the amount of radiation irradiated from the radiation irradiation device, and has an image sensor unit that can read pixel values ​​charged in the pixel units, and an AEC signal generation unit that generates the AEC signal based on the pixel values ​​of at least some of the pixel units of the image sensor unit.

[0011] In one embodiment, the AEC signal generating unit determines the specific point in time such that the sum of the first accumulated value of the pixel values ​​up to a specific point in time after irradiating with radiation by the radiation irradiation device and the second accumulated value of the pixel values ​​up to a point in time when irradiation by the radiation irradiation device is stopped at the specific point in time satisfies a reference value, determines the specific point in time as an AEC signal generation point in time for generating the AEC signal, and generates a first AEC signal at the AEC signal generation point in time and transmits the signal to the integrated control unit.

[0012] In one embodiment, the second accumulated value may be calculated as an accumulated value of the pixel value during a delay time from the specific point in time to the point in time when radiation irradiation from the radiation irradiation device is stopped.

[0013] In one embodiment, the AEC signal generation unit can determine a point in time that satisfies the following [Mathematical Formula 1] as the point in time at which the AEC signal is generated.

[0014] [Mathematical Formula 1]

[0015]

[0016] In one embodiment, the step of irradiating the subject with the radiation by the radiation irradiation device is divided into a pre-section and a main section, and the AEC signal generation unit calculates an additional irradiation time of the main section required based on a third accumulated value of the pixel value in the pre-section, the irradiation information of the radiation in the pre-section, and a predetermined reference value, and generates a second AEC signal at the irradiation completion time determined by the irradiation time of the main section and transmits the signal to the integrated control unit.

[0017] In addition, when the step of irradiating the radiation is the pre-interval, a first interval in which the pixel value increases non-linearly and a second interval in which the pixel value remains constant may be included in the pre-interval.

[0018] In addition, the AEC signal generation unit can determine the irradiation time of the main section by subtracting the third accumulated value from the reference value and calculating the additional irradiation time required based on the irradiation information of the radiation in the second section.

[0019] In addition, the AEC signal generation unit can determine the irradiation time or radiation irradiation completion time of the main section at the end point of the pre-section.

[0020] In one embodiment, the radiation irradiation by the radiation irradiation device is performed by dividing it into a pre-irradiation step and a main irradiation step, and a rest time exists between the pre-irradiation step and the main irradiation step, and the AEC signal generation unit generates the irradiation time of the main irradiation step or the radiation irradiation completion time of the main irradiation step as a second AEC signal based on the third accumulated value of the pixel value in the pre-irradiation step and transmits the signal to the integrated control unit.

[0021] In one embodiment, the second AEC signal may be generated and transmitted to the integrated control unit at the end of the pre-investigation step, during the pause time, or at the end of the pause time.

[0022] Additionally, the main investigation step may be started after the radiation control unit receives the second AEC signal.

[0023] In one embodiment, the AEC signal generation unit can transmit the AEC signal to the integrated control unit multiple times using the same wireless communication method.

[0024] In one embodiment, the AEC signal generation unit can transmit the AEC signal to the integrated control unit through different communication methods.

[0025] In one embodiment, the radiation control unit may stop the radiation irradiation if the AEC signal is not received for a predetermined radiation irradiation time after the radiation irradiation.

[0026] According to the present invention, when transmitting an AEC signal wirelessly from a radiation detector to a radiation irradiation device, even when a data transmission delay occurs in wireless communication, automatic exposure control (AEC) is accurately implemented, thereby minimizing unnecessary radiation exposure to a patient while irradiating an appropriate amount of radiation to secure image quality.

[0027] Figure 1 is a schematic diagram showing the configuration of a radiographic system according to one embodiment of the present invention;

[0028] Figure 2 is a block diagram showing the configuration of a radiographic system.

[0029] Figure 3 is a plan view illustrating an image sensor unit.

[0030] Figures 4 to 6 are graphs showing pixel values ​​of pixel units when radiation is irradiated by a radiation irradiation device of a radiographic system according to one embodiment.

[0031] FIG. 7 is a graph showing pixel values ​​of a pixel unit when radiation is irradiated by a radiation irradiation device of a radiographic system according to another embodiment.

[0032] FIG. 8 is a graph showing pixel values ​​of a pixel unit when radiation is irradiated by a radiation irradiation device of a radiographic system according to another embodiment.

[0033] Figure 9 is a block diagram showing the configuration of a radiographic system according to another embodiment;

[0034] Figure 10 is a block diagram illustrating the configuration of a radiographic system according to another embodiment.

[0035] Hereinafter, a detailed description will be given of a radiographic system according to an embodiment of the present invention with reference to the drawings.

[0036] FIG. 1 is a schematic diagram illustrating the configuration of a radiographic system (1000) according to one embodiment of the present invention.

[0037] Referring to FIG. 1, a radiographic system (1000) according to one embodiment of the present invention may include a radiation irradiation device (300) that irradiates radiation, a detector (100) that generates an image of a target object by radiation that has passed through the subject (H) and generates an AEC signal, and an integrated control unit (400) that receives the AEC signal and transmits it to the radiation irradiation device (300).

[0038] The above radiation irradiation device (300) may be equipped with a radiation generator (320) that generates radiation and a radiation control unit (330) that controls the radiation generator (320). The radiation may be irradiated from the radiation generator (320) toward a subject (H) through a collimator (310).

[0039] The radiation irradiated by the above radiation irradiation device (300) may be, for example, X-rays, but is not limited thereto and may be replaced with various other radiations. The following description assumes that the radiation is X-rays.

[0040] Fig. 2 is a block diagram illustrating the configuration of the above-described radiographic system (1000), and Fig. 3 is a plan view illustrating the image sensor unit (110). In Fig. 3, the scintillator panel (112) is omitted for convenience of illustration.

[0041] Referring to FIG. 2, the detector (100) according to the present invention is described as an indirect conversion method having a scintillator panel (112). However, the present invention is not limited thereto, and can also be applied to a direct conversion method in which, for example, photoconductive charges generated inside a photoconductive film by X-rays are directly conducted to a storage capacitor for charge accumulation by a high voltage.

[0042] Referring to FIG. 2, the detector (100) may be equipped with an image sensor unit (110) that can charge a plurality of pixel units (120) with charges proportional to the amount of radiation irradiated from the radiation irradiation device (300) and read the pixel values ​​charged in the pixel units (120), and an AEC signal generation unit (130) that generates an AEC signal (Automatic Exposure Control signal) based on the pixel values ​​of the pixel units (120) of the image sensor unit (110).

[0043] In this case, the radiographic system (1000) may be equipped with the integrated control unit (400) that receives the AEC signal and transmits it to the radiation control unit (330). The integrated control unit (400) may be equipped with, for example, a signal receiving unit (410) that wirelessly receives the AEC signal from the AEC signal generating unit (130), and an AEC control unit (420) that receives the AEC signal from the signal receiving unit (410) and transmits it to the radiation control unit (330).

[0044] Specifically, the image sensor unit (110) includes a plurality of pixel units (120) arranged in a matrix form, and may be equipped with an image detection unit (116) that charges the plurality of pixel units (120) with a charge proportional to the amount of radiation, a gate driving unit (114) that drives a gate in the image detection unit (116), and a readout unit (118) that reads a value output from each pixel unit (120). Furthermore, the image sensor unit (110) may further include a scintillator panel (112) that converts X-rays into fluorescence (visible light).

[0045] Referring to FIGS. 2 and 3, the image detection unit (116) may include a plurality of pixel units (120) arranged in a matrix form.

[0046] The above-described plurality of pixel units (120) may include, for example, a photoelectric conversion element, such as a photodiode that converts visible light into charge, although not shown in the drawing, a TFT (Thin-film transistor) that switches the accumulation and release of charge to a capacitor, and a capacitor to which charge converted from the photoelectric conversion element is supplied and accumulated.

[0047] Meanwhile, the plurality of pixel units (120) described above can be connected to a plurality of lines (122) and connected to a gate driver (114).

[0048] The above readout unit (118) can read the charge value charged in each pixel unit (120) and transmit the pixel value of the pixel unit (120) to the AEC signal generation unit (130).

[0049] For example, when performing a readout operation, the readout unit (118) can read the charge value of each pixel unit (120) to obtain analog data in the form of voltage, convert it into digital data, and transmit it to the AEC signal generation unit (130).

[0050] The AEC signal generation unit (130) can generate the AEC signal when the accumulated value of the pixel value is greater than a predetermined reference value.

[0051] Meanwhile, in the case of a radiographic system according to the prior art, when implementing an AEC function, a delay phenomenon due to wireless communication may occur in the process of wirelessly transmitting the AEC signal from the AEC signal generation unit (130) to the integrated control unit (400).

[0052] For example, a delay (hereinafter referred to as “delay time”) may occur between the time at which the AEC signal is generated in the AEC signal generating unit (130) and the time at which the radiation generator (320) in the radiation irradiation device (300) actually stops operating, thereby stopping radiation irradiation. If a delay time occurs between the time at which the AEC signal is generated and the time at which the radiation generator (320) stops operating, the patient’s radiation dose may increase.

[0053] In order to solve the above-mentioned problem, the present invention provides a radiographic system that does not increase the patient's radiation exposure despite the delay time.

[0054] Figure 4 is a graph showing the pixel values ​​of the pixel unit (120) when radiation is irradiated by the radiation irradiation device (300).

[0055] Referring to FIG. 4, the AEC signal generation unit (130) can determine the AEC signal generation time (or AEC signal generation time) based on the pixel value.

[0056] In one embodiment, the AEC signal generation unit (130) determines the AEC signal generation time point so that the total amount of radiation irradiated by the radiation irradiation device (300) satisfies a reference value. For example, the AEC signal generation unit (130) determines the AEC signal generation time point (T) after irradiating radiation by the radiation irradiation device (300). stop signal ) and the first accumulated value of the pixel values ​​up to the time point (T) of occurrence of the AEC signal stop signal ) at the point where radiation irradiation is stopped in the radiation irradiation device (300) (T stop xray ) so that the sum of the second accumulated values ​​of the pixel values ​​up to the point of occurrence of the AEC signal (T) satisfies the reference value. stop signal ) can be determined.

[0057] Here, the AEC signal generation time (T stop signal ) at the point where radiation irradiation is stopped in the radiation irradiation device (300) (T stop xray ) may correspond to the aforementioned delay time (aec_delay_time).

[0058] Therefore, a specific point in time is set as the AEC signal generation point (T) by the AEC signal generation unit (130). stop signal ), the AEC signal generation time (T stop signal ) the sum of the previous pixel values ​​(first accumulated value) and the time point of AEC signal generation (T stop signal ) After that, the sum of pixel values ​​(second accumulated value) during the delay time (aec_delay_time) can be calculated.

[0059] Next, the final sum obtained by adding the first accumulated value and the second accumulated value can be compared with a predetermined reference value. In this case, the AEC signal generation time (T) is set so that the final sum satisfies the reference value.stop signal ) can be determined.

[0060] Specifically, the AEC signal generation unit (130) can determine a point in time that satisfies the following [Mathematical Formula 1] as the point in time at which the AEC signal is generated.

[0061]

[0062] In the above [Mathematical Formula 1], 'pv n ' corresponds to the 'n'th pixel value of the pixel unit (120), 'aec_delay_time' corresponds to the delay time from the time of AEC signal generation to the time when radiation irradiation is actually stopped in the radiation irradiation device (300), and 'T interval ' can be defined as a standard time unit sampled to calculate the above pixel value.

[0063] For example, the AEC signal generation time (T stop signal ) The sum of the previous pixel values ​​(first accumulated value) corresponds to the shaded area in Fig. 5.

[0064] Referring to FIG. 5, the first accumulated value can be calculated by the following [Mathematical Formula 2].

[0065]

[0066] That is, when radiation is irradiated by the radiation irradiation device (300), the AEC signal is generated at the time (T stop signal ) is the time for 'N' standard time units (T interval ) can be sampled. In this case, the standard time unit (T) from the time of radiation exposure interval ) increases by 1 from 'n=0', and eventually reaches the AEC signal generation time (T stop signal ) can be said to be 'n=N'.

[0067] Therefore, the AEC signal generation time (T stop signal ) The sum of the previous pixel values ​​(the first accumulated value) is the pixel value (pv) while 'n' increases from '1' to 'N'. n) and corresponds to the shaded area in Figure 5.

[0068] Meanwhile, the AEC signal generation time (T stop signal ) After that, the sum of the pixel values ​​(second accumulated value) during the delay time (aec_delay_time) corresponds to the shaded area in Fig. 6.

[0069] Referring to Fig. 6, the second accumulated value can be estimated as in [Mathematical Formula 3] below.

[0070]

[0071] Here, 'pv N ' corresponds to the 'N'th pixel value of the above pixel unit (120), and specifically, the AEC signal generation time (T stop signal ) corresponds to the pixel value.

[0072] Additionally, the delay time (aec_delay_time) may be calculated in advance by a test operation of the radiographic system (1000) and stored in advance in the radiation control unit (330) or the AEC signal generation unit (130).

[0073] Therefore, the second accumulated value is the 'N'th pixel value (pv) of the pixel unit (120) as described in [Mathematical Formula 3]. N ) as the standard time unit (T) interval ) and multiplying it by the delay time (aec_delay_time). That is, the point in time (T) at which radiation exposure is stopped. stop xray ), the second accumulated value is the 'N'th pixel value (pv N ) and delay time (aec_delay_time) can be pre-calculated.

[0074] The second accumulated value calculated in this way corresponds to the shaded area in Fig. 6.

[0075] Meanwhile, in Fig. 6, the point in time (T) at which radiation irradiation is stopped in the radiation irradiation device (300)stop xray ) The radiation dose after this is generally very small and can be ignored.

[0076] Finally, as described in FIGS. 5 and 6, the AEC signal generation unit (130) generates the AEC signal at the time of generation (T) so that the sum of the first accumulated value and the second accumulated value satisfies the reference value. stop signal ) and determine the AEC signal generation time (T stop signal ) can generate a first AEC signal and transmit it to the integrated control unit (400).

[0077] When the first AEC signal is transmitted to the radiation control unit (330) by the integrated control unit (400), the radiation control unit (330) determines that the required radiation dose has been irradiated and can stop the operation of the radiation generator (320). Accordingly, even when the aforementioned delay time (aec_delay_time) occurs, an AEC function that provides only the required radiation dose to the patient can be implemented.

[0078] Meanwhile, FIG. 7 is a graph showing pixel values ​​of a pixel unit when radiation is irradiated by a radiation irradiation device of a radiographic system according to another embodiment.

[0079] Referring to Fig. 7, when the radiation is irradiated toward the subject (H) by the radiation irradiation device (300), the step of irradiating the radiation is a pre-section (D total ) and can be divided into this section (P).

[0080] In this case, the AEC signal generation unit (130) generates the pre-section (D total ) the third accumulated value of the pixel value, the investigation time of the pre-interval (T pre ) and the additional required investigation time of this section based on the predetermined reference value (T required ) is determined, and the investigation time (T) of the above section is determined. required) can generate the completion time of radiation exposure as the second AEC signal and transmit it to the integrated control unit (400).

[0081] For example, the above pre-interval (D total ) may include a first section (D1) in which pixel values ​​increase non-linearly and a second section (D2) in which the pixel values ​​remain approximately constant.

[0082] Here, the third accumulated value can be calculated by adding the sum of the pixel values ​​of the first section (D1) and the sum of the pixel values ​​of the second section (D2). The sum of the pixel values ​​of the first section (D1) can be calculated by sampling the first section (D1) in a standard time unit.

[0083] Next, the AEC signal generation unit (130) subtracts the third accumulated value from the reference value, calculates the additional investigation time required by the pixel value of the second section (D2) in which the pixel value is maintained constant, and calculates the investigation time (T) of this section. required ) can be calculated. In addition, if the radiation control unit (330) and the detector (100) are time synchronized, the irradiation time (T) of the section required ) can determine the completion time of radiation exposure.

[0084] That is, if the third accumulated value is subtracted from the reference value, the sum of pixel values ​​(or radiation dose) required in the main section (P) can be calculated. In this case, since the pixel values ​​are maintained almost constant after the second section (D2), the additional irradiation time required can be calculated using the pixel values ​​of the second section (D2), and thereby the irradiation time (T) of the main section required ) can be determined.

[0085] In the case of the above-described method, the AEC signal generation unit (130) generates the pre-section (D total ) at the end of the investigation time (T) of the above section required) or the completion time of radiation irradiation can be determined. The AEC signal generation unit (130) determines the irradiation time (T) of the above section. required ) or the completion time of radiation irradiation can be transmitted to the integrated control unit (400), and the irradiation time (T) of this section required ) or the completion time of radiation irradiation can be transmitted to the radiation control unit (330) through the integrated control unit (400).

[0086] Therefore, the radiation control unit (330) is configured to control the pre-section (D total ) After the end point of the radiation exposure, the time point of termination of the radiation exposure can be known in advance by the completion time of the radiation exposure, and thus the radiation exposure can be terminated when the completion time of the radiation exposure is reached.

[0087] For example, it is assumed that radiation is irradiated to the detector (100) at 12h 00m 00.000s, the reference value is 1500, and the pixel value is measured at 1ms intervals. Assuming that the cumulative value of the pixel value of the detector (100) becomes 200 during the first section (D1) of 3ms, and the pixel value is measured at 1ms intervals during the second section (D2) of 2ms, and the pixel value increases evenly by 100 to become 400, it can be determined that the pixel value increases evenly by 100 for 1ms after the second section (D2). In this case, the irradiation time (T) of this section required to reach the reference value required ) can be seen to be 11ms.

[0088] In conclusion, 12h 00m 00.016s, which is 16ms from the time of radiation exposure, corresponds to the time at which the reference value is reached. The AEC signal generation unit (130) generates the pre-interval (D total) can predict the end time of radiation exposure, that is, 12h 00m 00.005s, and transmit the end time of radiation exposure to the radiation control unit (330) through the integrated control unit (400). The radiation control unit (330) can check the end time of radiation exposure, wait until the completion time, and stop radiation exposure when the completion time is reached.

[0089] According to this embodiment, even if a delay in data transmission by wireless communication occurs, the AEC function can be implemented by appropriately terminating radiation exposure.

[0090] Figure 8 is a graph illustrating pixel values ​​of pixel units when radiation is irradiated by a radiation irradiation device of a radiographic system according to another embodiment. Figure 8 illustrates a process for implementing an AEC function when, after a pre-irradiation, there is a pause and then the main irradiation is performed again.

[0091] Referring to Fig. 8, compared to the embodiment of Fig. 7 described above, the step of irradiating the radiation is a step of pre-irradiating the radiation (D total ) and the radiation-examining stage (P), and the preliminary investigation stage (D) total ) and a predetermined pause time (T) between the above-mentioned investigation step (P) pause ) may exist.

[0092] Similar to the above-described embodiment, the AEC signal generation unit (130) performs the pre-investigation step (D total ) after the end of the above investigation time (T required ) or determine the completion time of radiation exposure.

[0093] That is, the AEC signal generation unit (130) is, in the pre-investigation step (D total ) the third accumulated value of the pixel value, the investigation time (T) of the preliminary investigation stage pre ) and based on predetermined reference values, the additional required investigation time (Trequired ) can be determined. In addition, the AEC signal generation unit (130) can determine the above-mentioned investigation time (T required ) can be generated as the second AEC signal and transmitted to the integrated control unit (400).

[0094] In this case, the above preliminary investigation stage (D total ) and stop the radiation exposure at the end of the rest time (T pause ) Afterwards, the main investigation step of irradiating again can be performed.

[0095] The above AEC signal generation unit (130) is used for the investigation time (T required ) or the time of this investigation (T required ) regarding the completion time of radiation irradiation according to the pre-irradiation step (D total ) can be transmitted to the integrated control unit (400) after the end of the AEC signal generation unit (130). In one embodiment, the AEC signal generation unit (130) performs a pre-investigation step (D total ) immediately after the above pause time (T pause ) during the above rest period (T pause ) can be transmitted to the integrated control unit (400) at the end point.

[0096] By this type of operation configuration, even if there is a delay in communication between the AEC signal generation unit (130) and the integrated control unit (400), the end point of radiation irradiation by the radiation control unit (330) can be accurately controlled, thereby preventing the risk of excessive radiation exposure.

[0097] In one embodiment, the AEC signal generation unit (130) is configured to generate a signal at the current irradiation time (T required ) is included in the second AEC signal and transmitted to the integrated control unit (400), the radiation control unit (330) starts the investigation after receiving the second AEC signal and starts the investigation time (T required ) can be used to conduct radiation exposure for a period of time corresponding to the time period.

[0098] In one embodiment, the pause time (T pause ) is already determined, the radiation control unit (330) sets the irradiation time (T required ) or the time of this investigation (T required ) The end time of radiation irradiation can be determined according to the second AEC signal regarding the completion time of radiation irradiation.

[0099] Meanwhile, as shown in the aforementioned FIG. 2, when the AEC signal generation unit (130) wirelessly transmits a signal to the signal reception unit (410) of the integrated control unit (400), in the case of the TCP / IP method during wireless communication, multiple signals cannot be transmitted at once because the method involves exchanging packets. Accordingly, if the transmission of the AEC signal is delayed due to a delay in the wireless communication itself, the AEC function cannot be properly implemented.

[0100] In this case, the AEC signal generation unit (130) can transmit the AEC signal multiple times using the same wireless communication method. For example, in the case of the UDP (User Datagram Protocol) method, since a one-way signal transmission method is possible, the AEC signal generation unit (130) can transmit the AEC signal multiple times in a relatively short time using the UDP method. The radiation control unit (330) can implement the AEC function by receiving the signal that arrives first among the transmitted signals.

[0101] Meanwhile, Fig. 9 is a block diagram illustrating the configuration of a radiographic system (2000) according to another embodiment for solving the aforementioned problem. In Fig. 9, the same components as in the aforementioned embodiment are denoted by the same drawing numbers.

[0102] Referring to FIG. 9, the AEC signal generation unit (130) can transmit the AEC signal to the integrated control unit (400') through different communication methods.

[0103] That is, in this embodiment, both the signal receiving unit (410') and the AEC control unit (420') of the integrated control unit (400') can wirelessly receive the AEC signal from the AEC signal generating unit (130).

[0104] For example, the AEC signal generation unit (130) can select two or more of various wireless communication methods, such as Wi-Fi, Bluetooth, UWB, etc., and transmit the AEC signal to the signal receiving unit (410') and the AEC control unit (420') using the different communication methods.

[0105] In this case, even if one signal arrives late due to delay, the AEC function can be implemented if the other signal arrives without delay.

[0106] In addition, Fig. 10 is a block diagram illustrating the configuration of a radiographic system (3000) according to another embodiment. In Fig. 10, the same components as in the above-described embodiment are denoted by the same drawing numbers.

[0107] Referring to FIG. 10, in the present embodiment, the integrated control unit (400”) may be configured by integrally forming the signal receiving unit and the AEC signal control unit of the aforementioned embodiment.

[0108] In this case, the AEC signal generation unit (130) can select two or more of various wireless communication methods, such as Wi-Fi, Bluetooth, UWB, etc., and simultaneously transmit the AEC signal to the integrated control unit (400”) by different communication methods.

[0109] In this case, even if one signal arrives late due to delay, the AEC function can be implemented if the other signal arrives without delay.

[0110] Meanwhile, in the above-described embodiments, the radiation control unit (330) may stop the radiation irradiation if it does not receive the AEC signal for a predetermined radiation irradiation time after the radiation irradiation.

[0111] For example, a very long wireless data transmission delay may occur intermittently after radiation exposure by the radiation irradiation device (300). In such a case, the radiation control unit (330) may stop radiation exposure after a predetermined time period has elapsed in order to prevent radiation overexposure if the AEC signal is not received during a predetermined radiation exposure time period after radiation exposure.

[0112] Here, the radiation exposure time can be set using the patient's clinical data, and can be automatically set using, for example, APR (Anatomical Programming).

[0113] While the present invention has been described above with reference to preferred embodiments, those skilled in the art will appreciate that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention as defined in the claims below. Therefore, any modified implementation that fundamentally includes the elements of the claims should be considered within the technical scope of the present invention.

Claims

1. A radiation irradiation device having a radiation generator that generates radiation and a radiation control unit that controls the radiation generator; A detector that generates an image of an object by radiation passing through the object (S) and generates an AEC signal; and An integrated control unit is provided that wirelessly receives the above AEC signal and transmits it to the radiation control unit. A radiographic system characterized in that the detector comprises an image sensor unit that can charge a plurality of pixel units with a charge proportional to the amount of radiation irradiated from the radiation irradiation device and read the pixel values ​​charged in the pixel units, and an AEC signal generation unit that generates the AEC signal based on the pixel values ​​of at least some of the pixel units of the image sensor unit.

2. In paragraph 1, The above AEC signal generation unit, The specific point in time is determined so that the sum of the first accumulated value of the pixel value up to a specific point in time after irradiating with radiation by the radiation irradiation device and the second accumulated value of the pixel value up to a point in time when irradiation by the radiation irradiation device is stopped from the specific point in time satisfies the reference value, A radiographic system characterized in that the specific point in time is determined as the AEC signal generation point in time that generates the AEC signal, and a first AEC signal is generated at the AEC signal generation point in time and transmitted to the integrated control unit.

3. In paragraph 2, The above second cumulative value is, A radiographic system characterized in that the accumulated value of the pixel value is calculated during the delay time from the specific point in time to the point in time when the radiation irradiation from the radiation irradiation device is stopped.

4. In paragraph 2, The above AEC signal generation unit determines the point in time that satisfies the following [Mathematical Formula 1] as the point in time when the AEC signal is generated. [Mathematical Formula 1] In the above [Mathematical Formula 1], pv n is the 'n'th pixel value of the pixel unit, 'aec_delay_time' is the delay time from the specific point in time to the point at which radiation irradiation from the radiation irradiation device is stopped, 'T interval ' is a radiographic imaging system characterized in that it is defined as a standard time unit sampled to calculate the above pixel value.

5. In paragraph 1, The step of irradiating the subject with the radiation using the radiation irradiation device is divided into a pre-section and a main section. A radiographic system characterized in that the AEC signal generation unit calculates the additional irradiation time of the main section required based on the third accumulated value of the pixel value in the pre-section, the irradiation information of the radiation in the pre-section, and a predetermined reference value, and generates a second AEC signal at the irradiation completion time determined by the irradiation time of the main section and transmits the signal to the integrated control unit.

6. In paragraph 5, If the step of irradiating the above radiation is the above pre-section, A radiographic system characterized by including a first section in which the pixel value increases non-linearly and a second section in which the pixel value remains constant.

7. In paragraph 6, The above AEC signal generation unit, A radiographic system characterized in that the third accumulated value is deducted from the reference value, the additional irradiation time required is calculated based on the irradiation information of the radiation in the second section, and the irradiation time of the main section is determined.

8. In paragraph 5, The above AEC signal generation unit, A radiographic system characterized in that the irradiation time or radiation irradiation completion time of the main section is determined at the end point of the above-mentioned preliminary section.

9. In paragraph 1, The radiation exposure by the above radiation exposure device is performed by dividing it into a pre-examination stage and a main irradiation stage, and there is a rest time between the pre-examination stage and the main irradiation stage. A radiographic system characterized in that the AEC signal generation unit generates a second AEC signal based on the third accumulated value of the pixel value in the pre-irradiation step, indicating the irradiation time of the main irradiation step or the completion time of the irradiation of the main irradiation step, and transmits the signal to the integrated control unit.

10. In paragraph 9, A radiographic system characterized in that the second AEC signal is generated at the end of the pre-investigation step, during the pause time, or at the end of the pause time and transmitted to the integrated control unit.

11. In paragraph 9, A radiographic system characterized in that the main investigation step starts after the radiation control unit receives the second AEC signal.

12. In paragraph 1, The above AEC signal generation unit A radiographic system characterized in that the AEC signal is transmitted multiple times to the integrated control unit using the same wireless communication method.

13. In paragraph 1, The above AEC signal generation unit A radiographic system characterized in that the AEC signals are transmitted to the integrated control unit through different communication methods.

14. In paragraph 1, A radiographic system characterized in that the radiation control unit stops the radiation irradiation if the AEC signal is not received for a predetermined radiation irradiation time after the radiation irradiation.

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