Photon counting imaging detector system based on hybrid anode

Abstract

The application belongs to the technical field of photon imaging detection, and particularly relates to a photon counting imaging detection system based on a mixed anode. The system comprises a vacuum sealed tube detector composed of a window coated with a photocathode, a microchannel plate stack and a mixed anode, and a signal processing circuit. The photocathode is used for converting photons incident through the window into photoelectrons. The microchannel plate stack is used for converting the photoelectrons into electron clouds. The mixed anode comprises a strip anode and a delay line anode arranged orthogonally, and the mixed anode transmits the collected charge short pulses of each channel to the signal processing circuit. The signal processing circuit calculates the two-dimensional coordinates of the photons based on the collected charge short pulses of each channel, and then transmits the two-dimensional coordinates of the photons to a terminal for imaging display. The application provides a photon counting imaging detection system based on a cross strip-delay line mixed anode, and solves the problem that the existing position sensitive anode detector cannot simultaneously have high spatial resolution and high temporal resolution.

Description

Technical Field

[0001] This invention belongs to the field of photon imaging and detection technology, and particularly relates to a photon counting imaging and detection system based on a hybrid anode. Background Technology

[0002] A microchannel plate is a two-dimensional, continuous electron-multiplying vacuum electronic device used to directly detect particles such as photons, electrons, ions, alpha particles, gamma rays, and cosmic rays. If a microchannel plate uses a position-sensitive anode (such as a wedge-shaped anode, delay line anode, or cross-strip anode) as the readout method, two-dimensional imaging with single-photon sensitivity can be achieved, known as a position-sensitive anode photon counting imaging detector. Position-sensitive anode photon counting imaging detectors are widely used in space astronomy, space plasma physics, and deep space exploration. Existing position-sensitive anode photon counting imaging detectors include cross-strip anode sealed tube imaging detectors in the visible-near-infrared band. This type of detector has the best spatial resolution and the highest count rate among all position-sensitive anode detectors, but its temporal resolution is on the order of nanoseconds (approximately 2 nanoseconds). Additionally, existing position-sensitive anode photon counting imaging detectors also include cross-delay line anode sealed tube imaging detectors in the visible-near-infrared band. Their spatial resolution and count rate are far inferior to those of the cross-strip anode sealed tube imaging detector, but their temporal resolution can reach 100 picoseconds. Figure 1 As shown, Figure 1 (a) in the diagram represents a cross-shaped strip anode. Figure 1 (b) in the figure is the anode of the cross delay line.

[0003] Compared to existing cross-strip anode-sealed tube imaging detectors, cross-strip anode-sealed tube imaging detectors have significant advantages in spatial resolution and count rate, while cross-delay line anode-sealed tube imaging detectors offer higher temporal resolution. For applications requiring both high temporal and spatial resolution, such as Raman imaging spectrometers, the position-sensitive anode photon counting imaging detector must possess both high spatial resolution in its longitudinal direction and a temporal resolution of less than 100 picoseconds. However, existing position-sensitive anode photon counting imaging detectors do not meet these requirements. Summary of the Invention

[0004] In view of this, the present invention aims to provide a photon counting imaging detection system based on a hybrid anode to solve the problem that existing position-sensitive anode detectors cannot simultaneously achieve both high temporal resolution and high temporal resolution. The present invention proposes a photon detection system based on a cross-strip-delay line hybrid anode to solve the problem that existing position-sensitive anode detectors cannot simultaneously achieve both high temporal resolution and high temporal resolution.

[0005] To achieve the above objectives, the technical solution created by this invention is implemented as follows: A photon counting imaging detection system based on a hybrid anode includes a vacuum-sealed tube detector and a signal processing circuit, comprising a window coated with a photocathode, a microchannel plate stack, and a hybrid anode. A photocathode is used to convert photons incident through a window into photoelectrons. Microchannel plate stacks are used to convert photoelectrons into electron clouds; The hybrid anode includes orthogonally arranged strip anodes and delay line anodes. The strip anodes and delay line anodes divide the electron cloud into multiple paths, and then transmit the short pulses of charge collected from each path to the signal processing circuit. The signal processing circuit calculates the two-dimensional coordinates of the photon based on the short charge pulses collected from each channel, and then transmits the two-dimensional coordinates of the photon to the terminal for imaging and display.

[0006] Furthermore, the signal processing circuit includes a multi-channel preamplifier circuit, a multi-channel shaping amplifier circuit, two short-pulse amplifiers, and two constant fraction discriminators. The number of channels in the multi-channel preamplifier circuit and the multi-channel shaping amplifier circuit is the same as the number of strip anodes. The output terminal of each strip anode is connected to the input terminal of the multi-channel preamplifier circuit, and the output terminal of the multi-channel preamplifier circuit is connected to the input terminal of the multi-channel shaping amplifier circuit. The delay line anode has two delay line electrodes, and the output terminal of each delay line electrode is connected to the short-pulse amplifier and the constant fraction discriminator in sequence. The short charge pulses output by each strip anode are converted into exponential voltage pulse signals by a multi-channel preamplifier circuit. The multi-channel shaping amplifier circuit converts the exponential voltage pulse signals output by each channel of the multi-channel preamplifier circuit into Gaussian voltage pulse signals. The short charge pulses output by each delay line electrode contained in the delay line anode are amplified by the corresponding short pulse amplifier. The constant fraction discriminator converts the corresponding amplified short charge pulses into the first digital pulse voltage signal.

[0007] Furthermore, the signal processing circuit also includes a digital processing circuit, which comprises an analog-to-digital converter, a microprocessor, and a data transmission module, wherein: The analog-to-digital converter module is used to convert each Gaussian voltage pulse signal into a second digital pulse signal and input each second digital pulse signal to the microprocessor. Each constant fractional discriminator inputs the first digital pulse voltage signal to the microprocessor. The microprocessor performs pulse identification and effective signal filtering on each first digital pulse signal and each second digital pulse signal, and calculates the two-dimensional coordinates of the photon using the centroid algorithm. The two-dimensional coordinates of the photon are then cached, packaged, and sent to the data transmission module. The data transmission module sends the packaged data transmitted by the microprocessor to the terminal for imaging and display.

[0008] Furthermore, the microprocessor includes an input buffer module, a pulse recognition module, a time measurement module, a peak extraction module, a centroid calculation module, an output buffer module, and an output control module, wherein: The input buffer module is used to buffer the first digital pulse signal and the second digital pulse signal of each channel; The pulse recognition module is used to record the pulse time interval between adjacent digital pulse signals on the same channel, identify the first digital pulse signal and the second digital pulse signal, and input each first digital pulse signal to the time measurement module and each second digital pulse signal to the peak extraction module. The time measurement module is used to calculate the time difference between the two first digital pulse signals; The peak extraction module is used to extract the peak values ​​of the waveforms of each second digital pulse signal; The centroid calculation module is used to calculate the peak waveform of each second digital pulse signal using the centroid algorithm of the strip anode to obtain the centroid coordinate array X, and to calculate the time difference based on the centroid algorithm of the delay line anode to obtain the centroid coordinate array Y, thus obtaining the two-dimensional coordinates of the incident photon. The output buffer module is used to buffer the two-dimensional coordinates of the corresponding photons output by the centroid calculation module; The output control module is used to package the two-dimensional coordinates of all photons cached by the output buffer module and send them to the data transmission module when the buffer area of ​​the output buffer module is full.

[0009] Furthermore, the centroid algorithm for the bar anode is either a Gaussian fitting algorithm or a centroid algorithm.

[0010] Furthermore, the multi-channel preamplifier circuit includes a charge amplifier and a pole-zero cancellation circuit. The charge amplifier is used to convert each short charge pulse into an exponential voltage pulse signal, and the pole-zero cancellation circuit is used to reduce the tail length of each exponential voltage pulse signal.

[0011] Compared with the prior art, the present invention can achieve the following beneficial effects: This invention presents a photon counting imaging detection system based on a hybrid anode, where the hybrid anode is a strip-delay line anode. This structure allows the detection system to achieve both high spatial and temporal resolution. The invention also includes a position readout circuit with data acquisition and single-photon imaging capabilities, allowing users to develop data acquisition programs to meet their specific needs. Attached Figure Description

[0012] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A schematic diagram of an existing anode structure in the background art of the present invention; Figure 2 A schematic diagram of the structure of the vacuum sealed tube imaging detector according to an embodiment of the present invention; Figure 3 A schematic diagram of the structure of the hybrid anode in an embodiment of the present invention; Figure 4 A schematic diagram of the signal processing circuit in an embodiment of the present invention; Figure 5 A schematic diagram of the structure of the digital processing circuit in an embodiment of the present invention; Figure 6 A schematic diagram of the structure of a microprocessor according to an embodiment of the present invention.

[0013] Explanation of reference numerals in the attached figures: 1. Window; 2. Microchannel board stack; 3. Hybrid anode; 4. Signal processing circuit; 5. Multi-channel preamplifier circuit; 6. Multi-channel shaping amplifier circuit; 7. Short pulse amplifier; 8. Constant fraction discriminator; 9. Digital processing circuit; 10. Analog-to-digital converter; 11. Microprocessor; 12. Data transmission module; 31. Strip anode; 32. Delay line anode; 321. Delay line electrode; 111. Input buffer module; 112. Pulse recognition module; 113. Time measurement module; 114. Peak extraction module; 115. Centroid calculation module; 116. Output buffer module; 117. Output control module. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0015] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0016] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0017] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0018] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0019] like Figure 2 As shown, the present invention provides a photon counting imaging detection system based on a hybrid anode, comprising a vacuum-sealed tube detector and a signal processing circuit 4 consisting of a window 1 coated with a photocathode, a microchannel plate stack 2, and a hybrid anode 3, wherein: The photocathode is used to convert photons incident through window 1 into photoelectrons; Microchannel plate stack 2 is used to convert photoelectrons into electron clouds; The hybrid anode 3 includes orthogonally arranged strip anode 31 and delay line anode 32. The strip anode 31 and delay line anode 32 divide the electron cloud into multiple paths, and then transmit the short pulses of charge collected from each path to the signal processing circuit 4. The signal processing circuit 4 calculates the two-dimensional coordinates of the photon based on the short charge pulses collected from each channel, and then transmits the two-dimensional coordinates of the photon to the terminal for imaging and display.

[0020] It should be noted that this invention combines the existing cross-strip anode 31 and cross-delay line anode 32. Since the fabrication processes of both are the same, a hybrid anode 3 composed of strip anode 31 and delay line anode 32 is proposed, which combines the advantages of both and has the advantages of high temporal resolution and high spatial resolution. The position readout electronics system combines the features of the two anode position readout circuits. The strip electrodes are respectively connected to the independent multi-channel preamplifier circuit 5 and analog-to-digital converter 10, while the delay line electrode 321 is connected to the time processing circuit (composed of short pulse amplifier 7 and constant fraction discriminator 8).

[0021] Furthermore, the hybrid anode 3, composed of the strip anode 31 and the delay line anode 32, is as follows: Figure 3 As shown, this system combines the advantages of both technologies to achieve high-precision and high-speed calculation of photon two-dimensional coordinates. The strip anode 31 directly extracts X-axis amplitude information through multiple electrodes, achieving high-resolution X-axis positioning through peak extraction and centroid algorithms. The delay line anode 32 uses only two electrodes, capturing the Y-axis time difference through the time measurement module 113 to complete positioning, significantly simplifying the hardware chain, reducing the number of amplifiers and other components, and lowering system complexity and cost. The hybrid architecture has a clear division of labor: the strip anode 31 ensures accuracy on the X-axis, while the delay line anode 32 improves efficiency on the Y-axis, balancing signal processing precision with rational resource utilization. Furthermore, it can filter effective signals through pulse recognition, further improving positioning accuracy and system operating speed, making it suitable for demanding photon detection scenarios.

[0022] Photons pass through incident window 1 and are converted into photoelectrons by the inner surface of window 1. An electric field exists between window 1 and the incident port of the microchannel plate, and the photoelectrons fly towards the incident port of the microchannel plate under the influence of the electric field. The microchannel plate stack 2 is a V-shaped structure of two stacked microchannel plates or a Z-shaped structure of three stacked microchannel plates, with high voltage applied to both ends. Photoelectrons continuously multiply inside the microchannel plate stack 2, forming a structure containing 10-1 photoelectrons at its exit end. 6 -10 7 An electron cloud of electrons is formed. A negative high voltage is applied between the microchannel plate stack 2 and the hybrid anode 3. Under the influence of the electric field, the electron cloud flies towards the hybrid anode 3, generating a charge pulse signal on the hybrid anode 3. Specifically, when the electron cloud lands on the corresponding strip anode 31, the strip anode 31 will generate a short charge pulse. When the electron cloud lands on the delay line anode 32, the output terminals of the two delay line electrodes 321 will generate short charge pulses. Therefore, each signal output from the hybrid anode 3 requires separate signal processing.

[0023] In some embodiments, such as Figure 4As shown, the signal processing circuit 4 includes a multi-channel preamplifier circuit 5, a multi-channel shaping amplifier circuit 6, two short pulse amplifiers 7, and two constant fraction discriminators 8. The number of channels in the multi-channel preamplifier circuit 5 and the multi-channel shaping amplifier circuit 6 is the same as the number of strip anodes 31. The output terminal of each strip anode 31 is connected to the input terminal of the multi-channel preamplifier circuit 5, and the output terminal of the multi-channel preamplifier circuit 5 is connected to the input terminal of the multi-channel shaping amplifier circuit 6. The delay line anode 32 has two delay line electrodes 321, and the output terminal of each delay line electrode 321 is connected to the short pulse amplifier 7 and the constant fraction discriminator 8 in sequence. The short charge pulses output by each strip anode 31 are converted into exponential voltage pulse signals by the multi-channel preamplifier circuit 5. The multi-channel shaping amplifier circuit 6 converts the exponential voltage pulse signals output by each channel of the multi-channel preamplifier circuit 5 into Gaussian voltage pulse signals. The short charge pulses output by each delay line electrode 321 contained in the delay line anode 32 are amplified by the corresponding short pulse amplifier 7. The constant fraction discriminator 8 converts the corresponding amplified short charge pulses into the first digital pulse voltage signal.

[0024] It should be noted that the short charge pulses output from each strip electrode are converted into amplified exponential voltage pulse signals by a single channel of the multi-channel preamplifier circuit 5. The multi-channel preamplifier circuit 5 consists of a charge amplifier and a pole-zero cancellation circuit. The charge amplifier converts the output signal of the strip anode 31 into an exponential voltage pulse signal with a long tail, and the pole-zero cancellation circuit reduces the tail length. Finally, the output signal of the multi-channel preamplifier circuit 5 is converted into a Gaussian voltage pulse signal with a shaping time of approximately 50 ns by the multi-channel shaping amplifier circuit 6. The shaping time of the multi-channel shaping amplifier circuit 6 is selected based on the requirements of the detector count rate and spatial resolution. The delay line anode 32 has only two electrodes, and the two output terminals are connected to the short pulse amplifier 7 and the constant fraction discriminator 8, respectively. The constant fraction discriminator 8 generates digital pulse voltage signals, and all pulse voltage signals enter the digital processing circuit 9.

[0025] In some embodiments, such as Figure 5 As shown, the signal processing circuit 4 also includes a digital processing circuit 9, which includes an analog-to-digital converter 10, a microprocessor 11, and a data transmission module 12, wherein: The analog-to-digital converter module is used to convert each Gaussian voltage pulse signal into a second digital pulse signal and input each second digital pulse signal to the microprocessor 11. Each constant fraction discriminator 8 inputs a first digital pulse voltage signal to the microprocessor 11. The microprocessor 11 performs pulse identification and effective signal filtering on each first digital pulse signal and each second digital pulse signal, and calculates the two-dimensional coordinates of the photon using the centroid algorithm. The two-dimensional coordinates of the photon are then cached, packaged, and sent to the data transmission module 12. The data transmission module 12 sends the packaged data transmitted by the microprocessor 11 to the terminal for imaging display.

[0026] It should be noted that the digital processing circuit 9 consists of an analog-to-digital converter module, a microprocessor 11, and a data transmission module 12. The analog-to-digital converter module is a multi-channel analog-to-digital converter 10 with a sampling accuracy of 12-14 bits and a sampling rate of 65-140 MSPS. It is used to convert the analog pulse voltage signal output from the charge pulse generated by the strip anode 31 through the multi-channel preamplifier circuit 5 and the multi-channel shaping amplifier circuit 6 into a digital pulse signal, which is then input to the microprocessor 11. At the same time, the digital pulse signal output from the constant fraction discriminator 8 corresponding to the delay line electrode 321 is also input to the microprocessor 11.

[0027] In some embodiments, such as Figure 6 As shown, the microprocessor 11 includes an input buffer module 111, a pulse recognition module 112, a time measurement module 113, a peak extraction module 114, a centroid calculation module 115, an output buffer module 116, and an output control module 117, wherein: Input buffer module 111 is used to buffer the first digital pulse signal and the second digital pulse signal of each channel; The pulse recognition module 112 is used to record the pulse time interval between adjacent digital pulse signals on the same channel, and to identify the first digital pulse signal and the second digital pulse signal. It also inputs each first digital pulse signal to the time measurement module 113 and each second digital pulse signal to the peak extraction module 114. The time measurement module 113 is used to calculate the time difference between the two first digital pulse signals; The peak extraction module 114 is used to extract the peak values ​​of the waveforms of each second digital pulse signal; The centroid calculation module 115 is used to calculate the peak waveform of each second digital pulse signal using the centroid algorithm of the strip anode 31 to obtain the centroid coordinate array X, and to calculate the time difference based on the centroid algorithm of the delay line anode 32 to obtain the centroid coordinate array Y, thus obtaining the two-dimensional coordinates of the incident photon. The output buffer module 116 is used to buffer the two-dimensional coordinates of the corresponding photon output by the centroid calculation module 115; The output control module 117 is used to package the two-dimensional coordinates of all photons cached by the output buffer module 116 and send them to the data transmission module 12 when the buffer of the output buffer module 116 is full.

[0028] It should be noted that the microprocessor 11 is a field-programmable gate array (FPGA), which is pre-programmed with functional modules such as input buffer, pulse recognition, peak extraction, centroid calculation, time measurement, output buffer, and output control. For a single photon event, only a small portion of the strip electrode channels and the two delay line channels will generate pulse waveforms. Therefore, pulse recognition is used to select the channel data to be processed, which saves computing resources and improves the running speed. At the same time, the pulse recognition module 112 records the pulse time interval, identifies the digital pulse signals from the strip anode 31 and the delay line anode 32, and sends them to the corresponding peak extraction module 114 and time measurement module 113. The peak extraction module 114 extracts the peak value of the output waveform of the strip anode 31, which is proportional to the charge of this anode. For Gaussian digital output waveforms, the peak value can be selected by point-by-point comparison. Subsequently, the peak values ​​of each strip electrode are input into the centroid algorithm of the strip anode 31 for calculation, and the measurement results of the time measurement module 113 are input into the centroid algorithm of the delay line anode 32 for calculation. The centroid algorithm of the strip anode 31 can use a Gaussian fitting algorithm or a centroid algorithm, and outputs a centroid coordinate array X. The centroid algorithm of the delay line anode 32 (which is existing technology, where the time difference of the output signal of the delay line anode 32 is proportional to the centroid coordinates of the electron cloud incident position) outputs a centroid coordinate array Y, where (X, Y) represents the two-dimensional coordinates of the incident photon. The centroid coordinate arrays are entered into a buffer. When the buffer is full, the data transmission control logic is triggered, and then the data is packaged and transmitted to the terminal (computer) through the data transmission module 12 (optical fiber) for imaging.

[0029] In some embodiments, the centroid algorithm for the strip anode 31 is a Gaussian fitting algorithm or a centroid algorithm.

[0030] In some embodiments, the multi-channel preamplifier circuit 5 includes a charge amplifier and a pole-zero cancellation circuit, wherein the charge amplifier is used to convert each short charge pulse into an exponential voltage pulse signal, and the pole-zero cancellation circuit is used to reduce the tail length of each exponential voltage pulse signal.

[0031] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0032] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A photon counting imaging detection system based on a hybrid anode, characterized in that: This includes a vacuum-sealed tube detector and signal processing circuitry consisting of a window coated with a photocathode, a microchannel plate stack, and a hybrid anode, wherein: A photocathode is used to convert photons incident through a window into photoelectrons. Microchannel plate stacks are used to convert photoelectrons into electron clouds; The hybrid anode includes orthogonally arranged strip anodes and delay line anodes. The strip anodes and delay line anodes divide the electron cloud into multiple paths, and then transmit the short pulses of charge collected from each path to the signal processing circuit. The signal processing circuit calculates the two-dimensional coordinates of the photon based on the short charge pulses collected from each channel, and then transmits the two-dimensional coordinates of the photon to the terminal for imaging and display.

2. The photon counting imaging detection system based on a hybrid anode according to claim 1, characterized in that: The signal processing circuit includes a multi-channel preamplifier circuit, a multi-channel shaping amplifier circuit, two short-pulse amplifiers, and two constant fraction discriminators. The number of channels in the multi-channel preamplifier circuit and the multi-channel shaping amplifier circuit is the same as the number of bar anodes. The output terminal of each bar anode is connected to the input terminal of the multi-channel preamplifier circuit, and the output terminal of the multi-channel preamplifier circuit is connected to the input terminal of the multi-channel shaping amplifier circuit. The delay line anode has two delay line electrodes, and the output terminal of each delay line electrode is connected to the short-pulse amplifier and the constant fraction discriminator in sequence. The short charge pulses output by each strip anode are converted into exponential voltage pulse signals by a multi-channel preamplifier circuit. The multi-channel shaping amplifier circuit converts the exponential voltage pulse signals output by each channel of the multi-channel preamplifier circuit into Gaussian voltage pulse signals. The short charge pulses output by each delay line electrode contained in the delay line anode are amplified by the corresponding short pulse amplifier. The constant fraction discriminator converts the corresponding amplified short charge pulses into the first digital pulse voltage signal.

3. The photon counting imaging detection system based on a hybrid anode according to claim 2, characterized in that: The signal processing circuit also includes a digital processing circuit, which comprises an analog-to-digital converter, a microprocessor, and a data transmission module, wherein: The analog-to-digital converter module is used to convert each Gaussian voltage pulse signal into a second digital pulse signal and input each second digital pulse signal to the microprocessor. Each constant fractional discriminator inputs the first digital pulse voltage signal to the microprocessor. The microprocessor performs pulse identification and effective signal filtering on each first digital pulse signal and each second digital pulse signal, and calculates the two-dimensional coordinates of the photon using the centroid algorithm. The two-dimensional coordinates of the photon are then cached, packaged, and sent to the data transmission module. The data transmission module sends the packaged data transmitted by the microprocessor to the terminal for imaging and display.

4. The photon counting imaging detection system based on a hybrid anode according to claim 3, characterized in that: The microprocessor includes an input buffer module, a pulse recognition module, a time measurement module, a peak extraction module, a centroid calculation module, an output buffer module, and an output control module, wherein: The input buffer module is used to buffer the first digital pulse signal and the second digital pulse signal of each channel; The pulse recognition module is used to record the pulse time interval between adjacent digital pulse signals on the same channel, identify the first digital pulse signal and the second digital pulse signal, and input each first digital pulse signal to the time measurement module and each second digital pulse signal to the peak extraction module. The time measurement module is used to calculate the time difference between the two first digital pulse signals; The peak extraction module is used to extract the peak values ​​of the waveforms of each second digital pulse signal; The centroid calculation module is used to calculate the peak waveform of each second digital pulse signal using the centroid algorithm of the strip anode to obtain the centroid coordinate array X, and to calculate the time difference based on the centroid algorithm of the delay line anode to obtain the centroid coordinate array Y, thus obtaining the two-dimensional coordinates of the incident photon. The output buffer module is used to buffer the two-dimensional coordinates of the corresponding photons output by the centroid calculation module; The output control module is used to package the two-dimensional coordinates of all photons cached by the output buffer module and send them to the data transmission module when the buffer area of ​​the output buffer module is full.

5. The photon counting imaging detection system based on a hybrid anode according to claim 4, characterized in that: The centroid algorithm for the bar anode is either Gaussian fitting or centroid algorithm.

6. The photon counting imaging detection system based on a hybrid anode according to claim 2, characterized in that: The multi-channel preamplifier circuit includes a charge amplifier and a pole-zero cancellation circuit. The charge amplifier is used to convert each short charge pulse into an exponential voltage pulse signal, and the pole-zero cancellation circuit is used to reduce the tail length of each exponential voltage pulse signal.

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