A real-time detection system and method for particle therapy beam irradiation depth

Abstract

This invention provides a real-time detection system and method for particle therapy beam irradiation depth. The real-time detection system includes a position-sensitive ionization chamber, a dose ionization chamber, and a data acquisition and processing module. The position-sensitive ionization chamber is located on one side of the patient's target area and on the beam side, and is used to measure the intensity of the radiation field generated near the patient's target area. The dose ionization chamber is located upstream of the isocenter and perpendicular to the beam injection direction, and is used to measure the beam intensity. The data acquisition and processing module is electrically connected to both the position-sensitive ionization chamber and the dose ionization chamber. Compared with existing technologies, this invention can simultaneously monitor the beam intensity and measure the irradiation depth of the ion beam in real time. It can be used for real-time feedback of irradiation depth during proton and carbon ion therapy, protecting the patient's normal organs and reducing the impact of depth uncertainty factors on the treatment effect.

Description

Technical Field

[0001] This invention relates to the field of particle therapy beam detection technology, and in particular to a real-time detection system and method for particle therapy beam irradiation depth. Background Technology

[0002] Due to the presence of the Bragg peak, proton and carbon ion tumor therapy offers greater precision compared to traditional radiotherapy methods, as the main dose can be accurately delivered to the patient's tumor target area via a beam delivery system. Furthermore, proton and carbon ion tumor therapy generates a high linear energy transfer (LET) process at the end of the beam's range, ensuring minimal damage to normal cells while killing cancer cells, thus exhibiting high safety.

[0003] Proton and carbon ion radiotherapy, as one of the most advanced radiotherapy methods currently available, offers the significant advantage of precisely controlling the radiation dose. However, due to factors such as organ movement, individual density differences, patient positioning accuracy, and variations in beam parameters, proton and carbon ion radiotherapy suffers from uncertain irradiation depth. This can negatively impact the precision of proton and carbon ion therapy. Therefore, measuring the beam irradiation depth is crucial for improving the accuracy of proton and carbon ion therapy.

[0004] Currently, existing technologies for measuring the depth of proton and carbon ion radiotherapy beams primarily rely on measuring the distribution and yield of transient gamma rays generated during treatment, or measuring the yield or track of charged particles generated during treatment and then using algorithms for inversion. For these two methods, the former suffers from a low transient gamma ray yield and slow response speed, making it susceptible to interference without collimation and reducing the measurement range when collimation is used. The latter is easily affected by the target area shape; in shallow treatments, secondary charged particles are easily blocked and cannot be measured. While measuring either transient gamma rays or charged particles can infer the treatment depth, the choice of radiation significantly increases the difficulty of measurement, drastically reduces statistical accuracy and measurement speed, and makes real-time measurement of beam irradiation depth difficult. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of the prior art by providing a real-time detection system and method for particle therapy beam irradiation depth. This system can measure the irradiation depth of the ion beam in real time while monitoring the beam intensity. It can be used for real-time feedback of irradiation depth during proton and carbon ion therapy, protecting the patient's normal organs and reducing the impact of depth uncertainty factors on the treatment effect.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a real-time detection system for the depth of particle therapy beam irradiation, comprising:

[0008] A position-sensitive ionization chamber is disposed on one side of the patient target area and on the beam side, and is used to measure the intensity of the radiation field generated near the patient target area;

[0009] A dose ionization chamber is located upstream of the isocenter and perpendicular to the beam injection direction; the dose ionization chamber is used to measure the intensity of the beam.

[0010] The acquisition and processing module is electrically connected to the position-sensitive ionization chamber and the dose ionization chamber, respectively.

[0011] Preferably, the position-sensitive ionization chamber includes a first cavity with an entrance window. The first cavity contains a stacked first high-voltage electrode, an amplifying electrode, and a collecting electrode. A first insulating plate is also provided between the first high-voltage electrode, the amplifying electrode, and the collecting electrode. The first cavity also has a first air inlet and a first air outlet communicating with its interior.

[0012] Preferably, the amplification electrode is a GEM electrode.

[0013] Preferably, the amplification electrode is formed by stacking multiple layers of the GEM electrode, and the first insulating plate is disposed between each two adjacent layers of the GEM electrode.

[0014] Preferably, the amplifying electrode is a wire mesh electrode.

[0015] Preferably, the dose ionization chamber includes a second cavity, which has a stacked signal electrode and a second high-voltage electrode. The second cavity has a beam injection window and a beam exit window. A second insulating plate is disposed between the signal electrode and the second high-voltage electrode. The second cavity also has a second air inlet and a second air outlet communicating with its interior.

[0016] Preferably, there are two sets of the second high-voltage electrodes, which are symmetrically arranged on both sides of the signal electrode.

[0017] Preferably, the acquisition and processing module is an electronics module, which has an ASIC chip, an analog-to-digital converter, and an FPGA chip.

[0018] Preferably, the ASIC chip is one of a multi-channel integral gating ASIC chip or a multi-channel I / V conversion ASIC chip.

[0019] In a second aspect, the present invention also provides a method for real-time detection of particle therapy beam irradiation depth, which uses the particle therapy beam irradiation depth real-time detection system as described in the first aspect above to detect the particle therapy beam irradiation depth in real time, including the following steps:

[0020] The location-sensitive ionization chamber is installed on one side of the patient's target area according to the patient's location, and the dose ionization chamber is installed upstream of the center of the accelerator, etc.

[0021] The position-sensitive ionization chamber and the dose ionization chamber synchronously and in real time detect the radiation field intensity and beam intensity near the patient's target area during the particle therapy beam irradiation, respectively, and generate radiation field intensity signals and beam intensity signals.

[0022] The acquisition and processing module acquires the radiation field intensity signal and beam intensity signal generated by the position-sensitive ionization chamber and the dose ionization chamber, performs signal conversion and data processing, calculates the beam irradiation depth information based on the linear relationship between the beam irradiation depth and the radiation field intensity normalized by the beam intensity, and compares it with the expected value. If the beam irradiation depth information exceeds the expected value, the acquisition and processing module sends an interlocking signal. At the same time, the acquisition and processing module uploads part or all of the original data and the processed data results to the host computer or front-end embedded system for data storage or publication.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] The position-sensitive ionization chamber and dose-sensitive ionization chamber of this invention can respectively measure the intensity of the radiation field generated during treatment and the intensity of the beam used in treatment. The acquisition and processing module can acquire and convert the signals generated during the measurements in the position-sensitive ionization chamber and dose-sensitive ionization chamber, and calculate the beam irradiation depth in real time based on the linear relationship between the irradiation depth of proton and carbon ion therapy and the radiation field intensity normalized by the beam intensity within a certain range. Therefore, this invention can measure the irradiation depth of the ion beam in real time while monitoring the beam intensity, and can be used for real-time feedback of the irradiation depth during proton and carbon ion therapy, protecting the patient's normal organs and reducing the impact of depth uncertainty factors on the treatment effect. Attached Figure Description

[0025] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the specific embodiments will be briefly described below. It should be noted that in all the drawings, the elements or parts are not necessarily drawn to actual scale.

[0026] Figure 1 This is a schematic diagram of the overall structure of the real-time detection system for particle therapy beam irradiation depth described in this embodiment of the invention;

[0027] Figure 2 This is an exploded view of the overall structure of the position-sensitive ionization chamber of the real-time detection system for particle therapy beam irradiation depth described in this embodiment of the invention.

[0028] Figure 3 This is an exploded view of the overall structure of the dose ionization chamber of the real-time detection system for particle therapy beam irradiation depth described in this embodiment of the invention.

[0029] Figure 4 This is a schematic diagram illustrating the linear relationship between the irradiation depth of carbon ions within a PMMA target and the normalized radiation field intensity.

[0030] In the picture:

[0031] 1. Position-sensitive ionization chamber; 1-1. First cavity; 1-2. Entrance window; 1-3. First high-voltage electrode; 1-4. Amplification electrode; 1-5. Collection electrode; 1-6. First insulating plate; 2. Dose ionization chamber; 2-1. Second cavity; 2-2. Signal electrode; 2-3. Second high-voltage electrode; 2-4. Beam entry window; 2-5. Beam exit window; 2-6. Second insulating plate; 3. Patient target area. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0033] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the system or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," etc., used to define components are merely for the convenience of distinguishing the aforementioned components. Unless otherwise stated, these terms have no special meaning and should not be construed as indicating or implying relative importance.

[0034] 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 can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0035] For proton and carbon ion tumor therapy, the irradiation depth is uncertain due to factors such as patient organ movement, individual density differences, patient positioning accuracy, and variations in beam parameters. This affects the precision of proton and carbon ion therapy. Therefore, measuring the beam irradiation depth is crucial for improving the precision of proton and carbon ion therapy. Currently, existing technologies for measuring the beam irradiation depth of proton and carbon ion radiotherapy mainly involve measuring the distribution and yield of transient gamma rays generated during treatment, or measuring the yield or track of charged particles generated during treatment and obtaining the result through algorithmic inversion. For these two measurement methods, the former significantly increases the complexity of the measurement system by selecting specific gamma rays in the radiation field, reducing statistical accuracy by two orders of magnitude, resulting in poor measurement accuracy and speed; therefore, this method is not widely used clinically. The latter is easily affected by changes in the target area shape, especially when the target area is thick, where the vast majority of charged particles are blocked, rendering it essentially ineffective. Therefore, the present invention provides a real-time detection system and method for particle therapy beam irradiation depth, which can measure the irradiation depth of the ion beam in real time while monitoring the beam intensity. It can be used for real-time feedback of irradiation depth during proton and carbon ion therapy, protecting the patient's normal organs and reducing the impact of depth uncertainty factors on the treatment effect.

[0036] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0037] Example 1

[0038] like Figures 1-3 As shown, this embodiment of the invention provides a real-time detection system for the irradiation depth of a particle therapy beam, comprising:

[0039] Position-sensitive ionization chamber 1 is located on one side of the patient target area 3 and on the beam side. Position-sensitive ionization chamber 1 is used to measure the intensity of the radiation field generated near the patient target area 3.

[0040] Dose ionization chamber 2 is located upstream of the isocenter and perpendicular to the beam injection direction. Dose ionization chamber 2 is used to measure the intensity of the beam.

[0041] The data acquisition and processing module is electrically connected to the position-sensitive ionization chamber 1 and the dose ionization chamber 2, respectively.

[0042] Since the irradiation depth of proton and carbon ion therapy is linearly related to the normalized radiation field intensity (normalized radiation field intensity = radiation field intensity / beam intensity) within a certain range, this invention can obtain the linear relationship between the irradiation depth of proton and carbon ion therapy and the normalized radiation field intensity in advance through experiments. During use, the position-sensitive ionization chamber 1 and the dose ionization chamber 2 can respectively detect the radiation field intensity and beam intensity generated near the patient's target area 3 in real time. The acquisition and processing module first acquires and processes the radiation field intensity signal and beam intensity signal generated by the position-sensitive ionization chamber 1 and the dose ionization chamber 2, then calculates the normalized radiation field intensity based on the converted signal, and finally calculates the real-time irradiation depth of proton and carbon ion therapy based on the linear relationship between the irradiation depth of proton and carbon ion therapy and the normalized radiation field intensity. Therefore, the embodiments of the present invention can measure the irradiation depth of the ion beam in real time while monitoring the beam intensity. This can be used for real-time feedback of irradiation depth during proton and carbon ion therapy, protecting the patient's normal organs and reducing the impact of depth uncertainty factors on the treatment effect.

[0043] Furthermore, such as Figure 2 As shown, the position-sensitive ionization chamber 1 includes a first cavity 1-1 with an entrance window 1-2. The first cavity 1-1 contains a stacked first high-voltage electrode 1-3, an amplifying electrode 1-4, and a collecting electrode 1-5. The collecting electrode 1-5 is electrically connected to the acquisition and processing module via a data cable, etc. A first insulating plate 1-6 is also provided between the first high-voltage electrode 1-3, the amplifying electrode 1-4, and the collecting electrode 1-5. The first insulating plate 1-6 is used to maintain insulation and isolation between the electrodes within the first cavity 1-1 and to provide a certain electrode spacing. The first cavity 1-1 also has a first air inlet and a first air outlet communicating with its interior. The first air inlet and the second air outlet are used to inject working gas and replace working gas, respectively. The working gas can be isobutane, a mixture of argon and methane, or CF4 gas, etc., used for proportional amplification.

[0044] The region between the first high-voltage electrode 1-3 and the amplification electrode 1-4 is the ionization region. The spacing between the ionization regions is controlled between 2mm and 100mm. The high-voltage electrode is connected to a -3000V high voltage, and the voltage difference between the high-voltage electrode and the amplification electrode 1-4 is 1400V.

[0045] Preferably, in this embodiment, the spacing between the ionization regions is 15 mm.

[0046] When the position-sensitive ionization chamber 1 of this embodiment is working, the secondary particles generated when the beam reacts with the target material in a nuclear reaction enter the ionization region under the action of the electric field in the position-sensitive ionization chamber 1 and interact with the working gas in the first cavity 1-1 to generate electron-ion pairs. Under the action of the electric field, the electron-ion pairs drift to the amplification electrode 1-4 for multiplication and amplification. After multiplication and amplification, the electron-ion pairs finally drift to the collection electrode 1-5 under the action of the electric field and generate a current signal on the collection electrode 1-5.

[0047] In this embodiment, by setting amplification electrodes 1-4 in the position-sensitive ionization chamber 1, the electron-ion pairs generated by the interaction between secondary particles and the working gas in the first cavity 1-1 can be multiplied and amplified. This can improve the response speed of the collecting electrodes 1-5, ensuring that the acquisition and processing module can acquire the current signal on the collecting electrodes 1-5 in a timely manner, so that this embodiment can measure the beam irradiation depth in a timely and accurate manner.

[0048] Furthermore, the amplifying electrodes 1-4 are GEM (Gaseous Electron Multipliers) electrodes. The voltage difference between the upper and lower surfaces of the GEM electrodes is 400V-1000V.

[0049] Furthermore, the amplification electrode 1-4 is composed of multiple layers of GEM electrodes stacked together, with a first insulating plate 1-6 disposed between each pair of adjacent GEM electrodes. The multiple layers of GEM electrodes can enhance the multiplication amplification effect of the amplification electrode 1-4 on electron-ion pairs, which can further reduce the size of the GEM electrodes and amplification electrode 1-4 in this embodiment, making the structure of the position-sensitive ionization chamber 1 more compact and easier to install.

[0050] It should be noted that when the amplification electrodes 1-4 include multiple layers of GEM electrodes, the specific number of layers of GEM electrodes can be set according to actual factors such as the size of the GEM electrodes and the size of the collection electrodes 1-5. This embodiment does not impose any restrictions on this.

[0051] Preferably, the amplification electrodes 1-4 in this embodiment include two layers of GEM electrodes. Each GEM layer is 0.5 mm thick, has a micropore diameter of 70 μm, and the distance between the two GEM layers is 1 mm. Each GEM electrode is connected to a voltage divider circuit to ensure a voltage difference of 800 V between its upper and lower surfaces.

[0052] It should be noted that the amplification electrodes 1-4 of the position-sensitive ionization chamber 1 of the present invention are not limited to the GEM electrodes described above. In other embodiments, other types of electrodes, such as wire mesh electrodes, can also be used. For example, in other embodiments of the present invention, wire mesh electrodes with a wire diameter of 25μm to 200μm and a wire spacing of 100μm to 1000μm can be selected as amplification electrodes 1-4.

[0053] Furthermore, such as Figure 3 As shown, the dose ionization chamber 2 includes a second cavity 2-1, which contains a stacked signal electrode 2-2 and a second high-voltage electrode 2-3. The signal electrode 2-2 is electrically connected to the acquisition and processing module via signal lines, etc. The second cavity 2-1 has a beam inlet window 2-4 and a beam outlet window 2-5. A second insulating plate 2-6 is provided between the signal electrode 2-2 and the second high-voltage electrode 2-3. The second insulating plate 2-6 is used to keep the signal electrode 2-2 and the second high-voltage electrode 2-3 insulated and isolated and to have a certain electrode spacing. The second cavity 2-1 also has a second air inlet and a second air outlet communicating with its interior. The second air inlet and the second air outlet are used to inject and replace the working gas into the second cavity 2-1. The working gas can be a single-component gas such as nitrogen, or a mixed gas such as air.

[0054] Preferably, there are two sets of second high-voltage electrodes 2-3, which are symmetrically arranged on both sides of the signal electrode 2-2. By setting one set of second high-voltage electrodes 2-3 on each side of the signal electrode 2-2, the error introduced by the unevenness of the signal electrode 2-2 can be basically eliminated, thereby improving the accuracy of the dose monitoring chamber measurement.

[0055] Furthermore, the acquisition and processing module is an electronics module, which includes an ASIC (Application Specific Integrated Circuit) chip, an analog-to-digital converter (ADC), and an FPGA (Field Programmable Gate Array) chip. The ASIC chip is electrically connected to the collection electrode 1-5 and the signal electrode 2-2, converting the current signal on these electrodes into a voltage signal. The ADC receives the voltage signal converted by the ASIC chip and converts it into a digital signal. The FPGA chip receives the digital signal converted by the ADC and calculates the beam irradiation depth information based on the received digital signal and the linear relationship between the pre-obtained irradiation depth for proton / carbon ion therapy and the radiation field intensity normalized by the beam intensity. This information is then compared with the expected value. When the beam irradiation depth information calculated by the FPGA chip deviates from the expected value, the FPGA chip can also send a hard interlock signal through digital I / O. Simultaneously, the FPGA chip uploads some or all of the raw data and the processed data results to a host computer or front-end embedded system for data storage or distribution.

[0056] It is understood that the ASIC chip in this embodiment can be selected from chips such as multi-channel integration gate ASIC chips and multi-channel I / V conversion ASIC chips. The position-sensitive ionization chamber 1 and the dose ionization chamber 2 can share a single ASIC chip or use different ASIC chips. When the position-sensitive ionization chamber 1 and the dose ionization chamber 2 use different ASIC chips, since the amplified radiation field signal is still smaller than the beam signal, the ASIC chip used in the position-sensitive ionization chamber 1 should have higher sensitivity.

[0057] Preferably, in this embodiment, the position-sensitive ionization chamber 1 and the dose ionization chamber 2 share a single ASIC chip, which ensures that the position-sensitive ionization chamber 1 and the dose ionization chamber 2 operate in complete synchronization.

[0058] The real-time particle therapy beam irradiation depth detection system provided in this embodiment of the invention is applicable not only to proton and carbon ion therapy devices that use pencil beam point scanning or grating scanning to achieve specific target area treatment, but also to treatment devices for proton and carbon ion pencil beam or scattered beam layered flash radiotherapy. Specifically, when using a pencil beam for conventional treatment, the real-time particle therapy beam irradiation depth detection system provided in this embodiment of the invention can be used to measure the depth of each point in point scanning, and can also be used to measure the beam irradiation depth within a certain time or range in the case of grating scanning. When using a pencil beam for FLASH treatment, the real-time particle therapy beam irradiation depth detection system provided in this embodiment of the invention is used to measure the depth of one layer of treatment, and can also measure the irradiation depth within a fixed time interval during treatment.

[0059] Example 2

[0060] Based on the real-time particle therapy beam irradiation depth detection system provided in Embodiment 1 above, this embodiment of the invention provides a real-time particle therapy beam irradiation depth detection method, specifically including the following steps:

[0061] Step 1: Based on the patient's location, install the position-sensitive ionization chamber 1 on one side of the patient's target area 3 and install the dose ionization chamber 2 upstream of the center of the accelerator, etc.

[0062] Step 2: The position-sensitive ionization chamber 1 and the dose ionization chamber 2 synchronously and in real time detect the radiation field intensity and beam intensity near the patient's target area 3 during particle therapy irradiation, respectively, and generate radiation field intensity signals and beam intensity signals.

[0063] Step 3: The acquisition and processing module acquires the radiation field intensity signal and beam intensity signal generated by the position-sensitive ionization chamber 1 and the dose ionization chamber 2, performs signal conversion and data processing, calculates the beam irradiation depth information based on the linear relationship between the beam irradiation depth and the radiation field intensity normalized by the beam intensity, and compares it with the expected value. If the beam irradiation depth information exceeds the expected value, the acquisition and processing module sends an interlock signal. At the same time, the acquisition and processing module uploads part or all of the original data and the processed data results to the host computer or front-end embedded system for data storage or publication.

[0064] The linear relationship between the beam irradiation depth and the radiation field intensity normalized by the beam intensity can be obtained through experiments and other methods. Figure 4 This is a schematic diagram illustrating the linear relationship between the irradiation depth of carbon ions within a PMMA (Polymethyl methacrylate) target and the normalized radiation field intensity.

[0065] The detection method provided in this embodiment can measure the irradiation depth of the beam in real time by analyzing the beam intensity and the radiation field intensity near the patient target area 3, and by establishing a linear relationship between the beam irradiation depth and the radiation field intensity normalized by the beam intensity. Specifically, this method improves the measurement accuracy of the beam irradiation depth by normalizing the radiation field intensity measured in the position-sensitive ionization chamber 1 with the beam intensity, reducing the impact of beam intensity variations on the measurement. Therefore, the detection method provided in this embodiment can measure the irradiation depth of the ion beam in real time while monitoring the beam intensity. This method can be used for real-time feedback of irradiation depth during proton and carbon ion therapy, protecting the patient's normal organs and reducing the impact of depth uncertainty factors on the treatment effect.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A real-time detection system for the depth of particle therapy beam irradiation, characterized in that, include: A position-sensitive ionization chamber (1) is disposed on one side of the patient target area (3) and on the beam side. The position-sensitive ionization chamber (1) is used to measure the intensity of the radiation field generated near the patient target area (3). A dose ionization chamber (2) is located upstream of the isocenter and perpendicular to the beam injection direction. The dose ionization chamber (2) is used to measure the intensity of the beam. The acquisition and processing module is electrically connected to the position-sensitive ionization chamber (1) and the dose ionization chamber (2), respectively. The acquisition and processing module acquires and converts the signals generated during the measurement of the position-sensitive ionization chamber (1) and the dose ionization chamber (2), and calculates the beam irradiation depth in real time based on the linear relationship between the irradiation depth of proton and carbon ion therapy and the radiation field intensity normalized by the beam intensity within a certain range.

2. The real-time detection system for particle therapy beam irradiation depth as described in claim 1, characterized in that, The position-sensitive ionization chamber (1) includes a first cavity (1-1), which has an entrance window (1-2). The first cavity (1-1) has a first high-voltage electrode (1-3), an amplifying electrode (1-4), and a collecting electrode (1-5) stacked inside. A first insulating plate (1-6) is also provided between the first high-voltage electrode (1-3), the amplifying electrode (1-4), and the collecting electrode (1-5). The first cavity (1-1) also has a first air inlet and a first air outlet communicating with its interior.

3. The real-time detection system for particle therapy beam irradiation depth as described in claim 2, characterized in that, The amplification electrodes (1-4) are GEM electrodes.

4. The real-time detection system for particle therapy beam irradiation depth as described in claim 3, characterized in that, The amplification electrode (1-4) is formed by stacking multiple layers of the GEM electrode, and the first insulating plate (1-6) is disposed between each two adjacent layers of the GEM electrode.

5. The real-time detection system for particle therapy beam irradiation depth as described in claim 2, characterized in that, The amplification electrodes (1-4) are wire mesh electrodes.

6. The real-time detection system for particle therapy beam irradiation depth as described in claim 1, characterized in that, The dose ionization chamber (2) includes a second cavity (2-1), in which a signal electrode (2-2) and a second high-voltage electrode (2-3) are stacked. The second cavity (2-1) has a beam injection window (2-4) and a beam emission window (2-5). A second insulating plate (2-6) is disposed between the signal electrode (2-2) and the second high-voltage electrode (2-3). The second cavity (2-1) also has a second air inlet and a second air outlet communicating with its interior.

7. The real-time detection system for particle therapy beam irradiation depth as described in claim 6, characterized in that, The second high-voltage electrode (2-3) consists of two sets, which are symmetrically arranged on both sides of the signal electrode (2-2).

8. The real-time detection system for particle therapy beam irradiation depth as described in claim 1, characterized in that, The acquisition and processing module is an electronics module, which includes an ASIC chip, an analog-to-digital converter, and an FPGA chip.

9. The real-time detection system for particle therapy beam irradiation depth as described in claim 8, characterized in that, The ASIC chip is either a multi-channel integral gating ASIC chip or a multi-channel I / V conversion ASIC chip.

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