A method and device for improving the dynamic range of a flat panel detector in a trigger mode

Abstract

The present invention relates to a method and apparatus for improving the dynamic range of a flat panel detector in a trigger mode. The method includes detecting a time interval of a trigger signal; when the time interval is the first time interval of the trigger signal, triggering and generating a pulse signal after the first time interval of the trigger signal, and using the pulse signal to control the flat panel detector to perform an image data stream readout once and generate a frame of image; when the time interval is the second or subsequent time interval of the trigger signal, triggering and generating a plurality of pulse signals within a time interval of the trigger signal, and using each pulse of the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once; performing arithmetic averaging processing on the plurality of image data streams read by the flat panel detector within a time interval of the trigger signal to generate a frame of image; The present invention can achieve the purpose of improving the dynamic range without additional operations by the user, greatly reducing the burden on the user.

Description

Technical Field

[0001] The present invention relates to the technical field of flat panel detectors, and particularly to a method and device for improving the dynamic range of a flat panel detector in a trigger mode. Background Art

[0002] A flat panel detector is a radiation detection device dedicated to X-ray imaging, and is widely used in radiation imaging fields such as dental CT, C-arm, and industrial non-destructive testing. In the application of a flat panel detector, the density change range of the object to be photographed is usually large, so a high requirement is put forward for the dynamic range of the flat panel detector. For users, a detector with a higher dynamic range means clearer details and lower dose. In the prior art, there are two methods for improving the dynamic range of a flat panel detector as follows:

[0003] The first method is to use a flat panel detector with different gains. First, a grayscale image is collected at each different gain, and then, for each pixel, a certain determination and selection are made on the grayscale values in different images. Finally, the grayscale values selected for each pixel are fused into a final grayscale image. In the final grayscale image, pixels with weaker received light intensity usually select the output grayscale of the image at a higher gain, while pixels with stronger received light intensity select the output grayscale of the image at a lower gain. Since a higher gain corresponds to a better signal-to-noise ratio and a lower gain corresponds to a higher saturation dose, the dynamic range corresponding to the finally fused image will be greatly improved. In this method, since the flat panel detector needs to be designed with multiple gain levels, the yield of its core optoelectronic conversion chip will be greatly reduced. At the same time, the gain difference of each pixel will exist due to the chip manufacturing difference, so it also needs to be combined with a very complex gain correction method to correct the gain of each pixel.

[0004] The second method is based on the idea of replacing a single long integration time acquisition at the same time with multiple short integration time acquisitions. The flat panel detector system usually uses a gigabit network to transmit data. Due to the gigabit network bandwidth limitation, the frame rate used by users is usually less than the highest frame rate that the detector can actually run. When the detector actually runs at N times the frame rate set by the user, since the integration time is reduced to 1 / N of the original, the saturation dose rate at this time will increase by N times, and the corresponding dynamic range will increase by √N times, where N is an integer greater than 1. It can be seen that the advantage of this method is that there is no need to design multiple gain levels and complex gain correction methods, and the dynamic range can be improved by adjusting the actual running frame rate inside the detector and performing a certain program of multi-frame averaging.

[0005] The acquisition modes of the flat panel detector include the free mode and the trigger mode. In the free mode, the user first sets the frame rate, and then when the user sets the start acquisition instruction, the detector continuously reads out signals at the preset frame rate; in the trigger mode, when the user sets the start acquisition instruction, the user uses an external signal to control the detector to read out signals. According to the differences in the trigger timing, the trigger mode is further divided into rising edge trigger, falling edge trigger, high level trigger, low level trigger, etc.

[0006] Taking the falling edge trigger as an example, when the user sets the start acquisition instruction, the user inputs a trigger signal from outside the detector. When the detector receives the falling edge of the trigger signal, the detector immediately starts to read out signals. Due to the row-by-row scanning readout method of the flat panel detector, there is a certain readout time Tr for its readout. This time is directly related to the design of the core optoelectronic conversion chip of the flat panel detector and is usually a fixed value in the same mode. The interval time between the falling edges of two adjacent external trigger signals is called the integration time. The integration time is controlled by the user and can be changed according to needs. During the continuous exposure of the ray source, the integration time is positively correlated with the received dose of the detector.

[0007] It can be seen that the implementation of Method 2 depends on the frame rate set by the user. When the user uses the trigger mode, the frame rate is determined by the interval of the trigger signals input by the user. At this time, the detector cannot predict the interval of the trigger signals input by the user, and Method 2 cannot be effectively implemented. Summary of the Invention

[0008] In order to solve the technical problems in the prior art, since the flat panel detector needs to design multiple gain levels, the yield of its core optoelectronic conversion chip will be greatly reduced; the differences in chip manufacturing will cause certain differences in the gain of each pixel. Therefore, it needs to cooperate with a very complex gain correction method to correct the gain of each pixel, and at the same time puts forward higher requirements for the user's hardware performance; it depends on the frame rate set by the user. When the user uses the trigger mode, the frame rate is determined by the interval of the trigger signals input by the user, and it is impossible to effectively improve the dynamic range of the flat panel detector in the trigger mode and other technical problems, the present invention provides a method and device for improving the dynamic range of a flat panel detector in the trigger mode.

[0009] The technical solution of the present invention to solve the above technical problems is as follows:

[0010] A method for improving the dynamic range of a flat panel detector in the trigger mode includes the following steps:

[0011] Detect a time interval of the trigger signal;

[0012] When the time interval is the first time interval of the trigger signal, a pulse signal is triggered and generated after the first time interval of the trigger signal, and the pulse signal is used to control the flat panel detector to perform an image data stream readout once;

[0013] An image data stream read out by the flat panel detector after the first time interval of the trigger signal is generated into a frame of image;

[0014] When the time interval is the second or subsequent time interval of the trigger signal, multiple pulse signals are triggered and generated within one time interval of the trigger signal, and each pulse among the multiple pulse signals is used to control the flat panel detector to perform an image data stream readout once;

[0015] The multiple image data streams read out by the flat panel detector within one time interval of the trigger signal are subjected to arithmetic averaging processing to generate a frame of image.

[0016] The beneficial effects of the present invention are as follows: The present invention detects the interval time of the user input trigger signal through the detection module, and the signal conversion module converts the external trigger signal. After the detection module detects the trigger signal interval time, the signal conversion module immediately automatically generates multiple related pulses internally. These related pulses directly control the detector to perform signal readout operations in the subsequent process. Compared with the first method in the background art, the present invention does not need to design multiple gain levels, improving the yield of the core optoelectronic conversion chip; and the present invention does not need to consider complex gain correction methods, reducing the complexity of the user's hardware and operation; compared with the second method in the background art, the present invention overcomes the problem that it is impossible to effectively achieve N-fold preset frame rate acquisition in the trigger mode, and thus impossible to achieve the improvement of the dynamic range. The method for improving the dynamic range of the present invention has clear and definite functions, consumes less computing resources, and can achieve the purpose of improving the dynamic range without additional operations by the user, greatly reducing the burden on the user.

[0017] On the basis of the above technical solution, the present invention can also be improved as follows.

[0018] Further, the trigger mode of the pulse signal is rising edge trigger or falling edge trigger or high level trigger or low level trigger.

[0019] Further, when the time interval is the first time interval of the trigger signal, a pulse signal is triggered and generated after the first time interval of the trigger signal, and the pulse signal is used to control the flat panel detector to perform an image data stream readout once, which specifically includes the following steps:

[0020] When the time interval is the first time interval of the trigger signal, a pulse signal is triggered and generated after the first time interval of the trigger signal and within the second time interval;

[0021] The pulse signal is used to control the flat panel detector to perform an image data stream readout once.

[0022] Further, when the time interval is the second time interval of the trigger signal, multiple pulse signals are triggered and generated within one time interval of the trigger signal, and each pulse among the multiple pulse signals is used to control the flat panel detector to perform an image data stream readout once. The specific steps are as follows:

[0023] When the time interval is the second time interval of the trigger signal, multiple pulse signals are triggered and generated after a pulse signal generated within the second time interval of the trigger signal and after the first time interval of the trigger signal;

[0024] Each pulse among the multiple pulse signals is used to control the flat panel detector to perform an image data stream readout once.

[0025] Further, the number of pulses in the multiple pulse signals triggered and generated within one time interval of the trigger signal and the time required for the flat panel detector to perform an image data stream readout once satisfy the following formula:

[0026]

[0027] Wherein, T represents the duration of one time interval, N represents the number of pulses in the multiple pulse signals triggered and generated within one time interval of the trigger signal, and Tr represents the time required for the flat panel detector to perform an image data stream readout once.

[0028] To solve the above technical problems, the present invention further provides a device for improving the dynamic range of a flat panel detector in a trigger mode. The specific technical solution is as follows:

[0029] A device for improving the dynamic range of a flat panel detector in a trigger mode, including a detection module and a signal conversion module;

[0030] The detection module is used to detect one time interval of the trigger signal;

[0031] When the time interval is the first time interval of the trigger signal, the signal conversion module is configured to trigger and generate a pulse signal after the first time interval of the trigger signal, and use the pulse signal to control the flat panel detector to perform an image data stream readout once; wherein, the flat panel detector generates a frame of image from the image data stream read out once after the first time interval of the trigger signal.

[0032] When the time interval is the second or a time interval after the second of the trigger signal, the signal conversion module is configured to trigger and generate a plurality of pulse signals within one time interval of the trigger signal, and use each pulse of the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once; wherein, the flat panel detector performs arithmetic averaging on the plurality of image data streams read out within one time interval of the trigger signal to generate a frame of image.

[0033] Further, the trigger mode of the pulse signal is rising edge trigger or falling edge trigger or high level trigger or low level trigger.

[0034] Further, when the time interval is the first time interval of the trigger signal, the signal conversion module is specifically configured to trigger and generate a pulse signal after the first time interval of the trigger signal and within the second time interval; and use the pulse signal to control the flat panel detector to perform an image data stream readout once.

[0035] Further, when the time interval is the second time interval of the trigger signal, the signal conversion module is specifically configured to trigger and generate a plurality of pulse signals within the second time interval of the trigger signal and after a pulse signal generated after the first time interval of the trigger signal; and use each pulse of the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once.

[0036] Further, the number of pulses in the plurality of pulse signals triggered and generated within one time interval of the trigger signal and the time required for the flat panel detector to perform an image data stream readout once satisfy the following formula:

[0037]

[0038] Wherein, T represents the duration of one time interval, N represents the number of pulses in the plurality of pulse signals triggered and generated within one time interval of the trigger signal, and Tr represents the time required for the flat panel detector to perform an image data stream readout once. Description of the Drawings

[0039] Figure 1It is a flowchart of a method for improving the dynamic range of a flat panel detector in a trigger mode in an embodiment of the present invention;

[0040] Figure 2 It is a falling edge trigger timing diagram for improving the dynamic range of a flat panel detector in a falling edge trigger mode in the prior art in an embodiment of the present invention;

[0041] Figure 3 It is the falling edge trigger timing for improving the dynamic range of a flat panel detector in a falling edge trigger mode in a method for improving the dynamic range of a flat panel detector in a trigger mode in an embodiment of the present invention Figure 1 ;

[0042] Figure 4 It is the falling edge trigger timing for improving the dynamic range of a flat panel detector in a falling edge trigger mode in a method for improving the dynamic range of a flat panel detector in a trigger mode in an embodiment of the present invention Figure 2 。 Detailed implementation manners

[0043] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0044] Embodiment 1

[0045] As Figure 1 shown, this embodiment provides a method for improving the dynamic range of a flat panel detector in a trigger mode, including the following steps:

[0046] A method for improving the dynamic range of a flat panel detector in a trigger mode, including the following steps:

[0047] S1. Detect a time interval of the trigger signal;

[0048] S2. When the time interval is the first time interval of the trigger signal, generate a pulse signal after the first time interval of the trigger signal, and use the pulse signal to control the flat panel detector to perform an image data stream readout once;

[0049] The specific steps are as follows:

[0050] When the time interval is the first time interval of the trigger signal, generate a pulse signal after the first time interval of the trigger signal and within the second time interval; use the pulse signal to control the flat panel detector to perform an image data stream readout once.

[0051] S3. Generate a frame of image from the image data stream read out by the flat panel detector after the first time interval of the trigger signal;

[0052] S4. When the time interval is the second time interval of the trigger signal or a time interval after the second one, within one time interval of the trigger signal, trigger and generate a plurality of pulse signals, and use each pulse among the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once;

[0053] Specifically, when the time interval is the second time interval of the trigger signal, within the second time interval of the trigger signal and after a pulse signal generated after the first time interval of the trigger signal, trigger and generate a plurality of the pulse signals; use each pulse among the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once.

[0054] S5. Perform arithmetic mean processing on the multiple image data streams read out by the flat panel detector within one time interval of the trigger signal to generate one frame of image.

[0055] Among them, the trigger mode of the pulse signal is rising edge trigger or falling edge trigger or high level trigger or low level trigger. Falling edge trigger means that one time interval of the trigger signal is the time interval between two adjacent falling edges of the trigger signal; rising edge trigger means that one time interval of the trigger signal is the time interval between two adjacent rising edges of the trigger signal; high level trigger means that one time interval of the trigger signal is the duration of a high level of the trigger signal; low level trigger means that one time interval of the trigger signal is the duration of a low level of the trigger signal.

[0056] Preferably, the number of pulses among the plurality of pulse signals triggered and generated within one time interval of the trigger signal and the time required for the flat panel detector to perform an image data stream readout once satisfy the following formula:

[0057]

[0058] Among them, T represents the duration of one time interval, N represents the number of pulses among the plurality of pulse signals triggered and generated within one time interval of the trigger signal, and Tr represents the time required for the flat panel detector to perform an image data stream readout once.

[0059] Such as Figure 2As shown below, taking the falling-edge trigger as an example, after the user sets the start acquisition command, the user inputs a trigger signal from outside the detector. When the detector receives the falling edge of the trigger signal, the detector immediately starts signal readout. Due to the row-by-row scanning readout method of the flat-panel detector, there is a certain readout time Tr for its readout. This time is directly related to the design of the core optoelectronic conversion chip of the flat-panel detector and is usually a fixed value in the same mode. The interval time between the falling edges of two adjacent external trigger signals is called the integration time. The integration time is controlled by the user and can be changed according to needs. During the exposure of a continuous radiation source, the integration time is positively correlated with the received dose of the detector.

[0060] It can be seen that the implementation of Method 2 depends on the frame rate set by the user. When the user uses the trigger mode, the frame rate is determined by the interval of the trigger signals input by the user. In this case, Method 2 cannot be effectively implemented.

[0061] As Figure 3 shown, a method for improving the dynamic range of a flat-panel detector in the trigger mode includes the following steps:

[0062] ① Set the start acquisition command;

[0063] ② Set the jump edge moment of the nth trigger signal as kn and take the time between moment k2 and moment k1 as the integration time T;

[0064] ③ Generate a fast pulse inside at moment k2 to control the detector to perform signal readout, and use the image data stream of this time to generate the image corresponding to the first trigger signal;

[0065] ④ Between moment k2 and k3, generate N pulses with a time interval of T / N inside, corresponding to the detector performing N times of signal readout. After arithmetic averaging the N image data streams, generate the image corresponding to the second trigger signal;

[0066] ⑤ Repeat step ④ until the user sets the stop acquisition command.

[0067] As Figure 4 shown, in this example, the trigger mode uses the falling-edge mode, and the actual acquisition frame rate of the detector is 3 times the frame rate actually required by the user. The corresponding specific steps are as follows:

[0068] 1) The user sets the start acquisition command;

[0069] 2) Set the jump edge moment of the nth trigger signal as kn, and the internal counter of the detector records kn. Take the time between moment k2 and moment k1 as the integration time T;

[0070] 3) At time k2, a fast pulse is generated inside the detector to control signal readout, and the image data corresponding to the first trigger signal is generated using the image data stream at this time;

[0071] 4) During the time between time k2 and k3, three pulses with a time interval of T / 3 are generated inside the detector, corresponding to three signal readouts of the detector. The image data corresponding to the second trigger signal is generated after arithmetic averaging of the three image data streams;

[0072] 5) Repeat step 4) until the user sets the stop acquisition instruction.

[0073] In this embodiment, since the output pulse 1 of the trigger signal conversion module occupies a part of the integration time, the interval time between pulse 1 and pulse 2-1 is less than T / 3. However, considering that the width of pulse 1 can be set to the microsecond level, while the integration time is usually in the millisecond level, the interval time here is approximately equal to T / 3, which does not affect the final test result.

[0074] The ratio N between the actual frame rate of the detector and the frame rate required by the user is a positive integer greater than or equal to 2; to avoid transmission bandwidth limiting the network rate available to the user, the arithmetic averaging operation mentioned in step 4) needs to be implemented in the hardware of the flat panel detector.

[0075] Comparing the embodiment based on the present invention with the traditional method, it can be seen that the number of trigger signals input by the user is consistent with the number of output image data streams, and there is no loss of integration time. Functionally, it fully meets the user's use and does not require additional operations by the user. At the same time, since the integration time is disassembled into three parts, the saturation dose rate under a single integration time is correspondingly increased by 3 times, and the corresponding dynamic range is increased by times

[0076] The embodiment of the present invention does not need to design multiple gain levels, which improves the yield of the core optoelectronic conversion chip; and the present invention does not need to consider complex gain correction methods, which reduces the complexity of the user's hardware and operation; it overcomes the problem that it is impossible to effectively achieve N-fold preset frame rate acquisition in the trigger mode, and thus impossible to achieve an increase in the dynamic range.

[0077] Embodiment 2

[0078] Based on Embodiment 1, a device for improving the dynamic range of a flat panel detector in the trigger mode includes a detection module and a signal conversion module;

[0079] The detection module is used to detect a time interval of the trigger signal;

[0080] When the time interval is the first time interval of the trigger signal, the signal conversion module is configured to trigger and generate a pulse signal after the first time interval of the trigger signal, and use the pulse signal to control the flat panel detector to perform an image data stream readout once; wherein, the flat panel detector generates a frame of image from the image data stream read out once after the first time interval of the trigger signal.

[0081] When the time interval is the second or subsequent time interval of the trigger signal, the signal conversion module is configured to trigger and generate a plurality of pulse signals within one time interval of the trigger signal, and use each pulse of the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once; wherein, the flat panel detector performs arithmetic averaging on the plurality of image data streams read out within one time interval of the trigger signal to generate a frame of image.

[0082] The trigger mode of the pulse signal is rising edge trigger or falling edge trigger or high level trigger or low level trigger.

[0083] When the time interval is the first time interval of the trigger signal, the signal conversion module is specifically configured to trigger and generate a pulse signal after the first time interval of the trigger signal and within the second time interval; and use the pulse signal to control the flat panel detector to perform an image data stream readout once.

[0084] When the time interval is the second time interval of the trigger signal, the signal conversion module is specifically configured to trigger and generate a plurality of pulse signals after a pulse signal generated after the first time interval of the trigger signal and within the second time interval of the trigger signal; and use each pulse of the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once.

[0085] The number of pulses in the plurality of pulse signals triggered and generated within one time interval of the trigger signal and the time required for the flat panel detector to perform an image data stream readout once satisfy the following formula:

[0086]

[0087] wherein, T represents the duration of one time interval, N represents the number of pulses in the plurality of pulse signals triggered and generated within one time interval of the trigger signal, and Tr represents the time required for the flat panel detector to perform an image data stream readout once.

[0088] The embodiment of the present invention sets a detection module, uses the detection module to detect the interval time of the user input trigger signal, sets a signal conversion module, uses the detection module to detect the interval time of the trigger signal, and then automatically generates multiple related pulses inside the trigger signal conversion module. These related pulses directly control the detector to perform signal reading operation in the subsequent process. The function of the device for improving the dynamic range provided by the embodiment of the present invention is clear and definite, and the computing resources consumed are also less. At the same time, the purpose of improving the dynamic range can be achieved without the user performing additional operations, which greatly reduces the burden on the user.

[0089] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the concept and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for improving the dynamic range of a flat panel detector in a trigger mode, characterized in that, Comprising the following steps: Detecting a time interval of a trigger signal; When the time interval is the first time interval of the trigger signal, triggering and generating a pulse signal after the first time interval of the trigger signal, and using the pulse signal to control a flat panel detector to perform an image data stream readout once; Generating a frame of image from the image data stream read out once by the flat panel detector after the first time interval of the trigger signal; When the time interval is the second or a time interval after the second of the trigger signal, triggering and generating a plurality of pulse signals within a time interval of the trigger signal, and using each pulse of the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once; Performing arithmetic averaging on the plurality of image data streams read out by the flat panel detector within a time interval of the trigger signal to generate a frame of image.

2. The method for improving the dynamic range of a flat panel detector in a trigger mode according to claim 1, wherein, The triggering mode of the pulse signal is rising edge triggering or falling edge triggering or high level triggering or low level triggering.

3. The method for improving the dynamic range of a flat panel detector in a trigger mode according to claim 1, wherein When the time interval is the first time interval of the trigger signal, triggering and generating a pulse signal after the first time interval of the trigger signal, and using the pulse signal to control the flat panel detector to perform an image data stream readout once, specifically comprising the following steps: When the time interval is the first time interval of the trigger signal, triggering and generating a pulse signal after the first time interval of the trigger signal and within the second time interval; Using the pulse signal to control the flat panel detector to perform an image data stream readout once.

4. The method for improving the dynamic range of a flat panel detector in a trigger mode according to claim 1, wherein: When the time interval is the second time interval of the trigger signal, triggering and generating a plurality of pulse signals within a time interval of the trigger signal, and using each pulse of the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once, specifically comprising the following steps: When the time interval is the second time interval of the trigger signal, triggering and generating a plurality of the pulse signals within the second time interval of the trigger signal and after a pulse signal generated after the first time interval of the trigger signal; Using each pulse of the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once.

5. The method for improving the dynamic range of a flat panel detector in a trigger mode according to any one of claims 1 to 4, characterized in that, The number of pulses in the plurality of pulse signals triggered and generated within a time interval of the trigger signal and the time required for the flat panel detector to perform an image data stream readout once satisfy the following formula: Wherein, T represents the duration of a time interval, N represents the number of pulses in the plurality of pulse signals triggered and generated within a time interval of the trigger signal, and Tr represents the time required for the flat panel detector to perform an image data stream readout once.

6. A device for improving the dynamic range of a flat panel detector in a trigger mode, characterized in that, Comprising a detection module and a signal conversion module; The detection module is used for detecting a time interval of a trigger signal; When the time interval is the first time interval of the trigger signal, the signal conversion module is configured to trigger and generate a pulse signal after the first time interval of the trigger signal, and use the pulse signal to control the flat panel detector to perform an image data stream readout once; wherein, the flat panel detector generates a frame of image from the image data stream read out once after the first time interval of the trigger signal. When the time interval is the second time interval or a time interval after the second time interval of the trigger signal, the signal conversion module is configured to trigger and generate a plurality of pulse signals within a time interval of the trigger signal, and use each pulse of the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once; wherein, the flat panel detector performs arithmetic averaging on the plurality of image data streams read out within a time interval of the trigger signal to generate a frame of image.

7. The device for improving the dynamic range of a flat panel detector in a trigger mode according to claim 6, wherein The trigger mode of the pulse signal is rising edge trigger or falling edge trigger or high level trigger or low level trigger.

8. The device for improving the dynamic range of a flat panel detector in a trigger mode according to claim 6, wherein When the time interval is the first time interval of the trigger signal, the signal conversion module is specifically configured to trigger and generate a pulse signal after the first time interval of the trigger signal and within the second time interval; and use the pulse signal to control the flat panel detector to perform an image data stream readout once.

9. The device for improving the dynamic range of a flat panel detector in a trigger mode according to claim 6, wherein When the time interval is the second time interval of the trigger signal, the signal conversion module is specifically configured to trigger and generate a plurality of the pulse signals after a pulse signal generated after the first time interval of the trigger signal and within the second time interval of the trigger signal; and use each pulse of the plurality of pulse signals to control the flat panel detector to perform an image data stream readout once.

10. The device for improving the dynamic range of a flat panel detector in a trigger mode according to any one of claims 6 to 9, characterized in that, The following formula is satisfied between the number of pulses in the plurality of pulse signals triggered and generated within a time interval of the trigger signal and the time required for the flat panel detector to perform an image data stream readout once: Wherein, T represents the duration of a time interval, N represents the number of pulses in the plurality of pulse signals triggered and generated within a time interval of the trigger signal, and Tr represents the time required for the flat panel detector to perform an image data stream readout once.

Images