Time-of-flight based hydrogen-helium isotope online analysis device and method

Abstract

The present application relates to the technical field of isotope detection, in particular to a hydrogen-helium isotope on-line analysis device based on time of flight, comprising a cavity, a laser, a rack, an extraction electrode, a film, a slit and a detector arranged in the cavity, wherein a vacuum pump is connected to the outside of the cavity to make the cavity in a vacuum state; the laser uses pulsed laser to ionize hydrogen-helium isotopes on the rack into hydrogen positive ions and helium positive ions through an incident window arranged on the cavity, and uses the pulsed laser emission time as the start time signal of the time of flight detection system; the hydrogen positive ions and the helium positive ions are extracted and accelerated to appropriate energy by the electric field between the rack and the extraction electrode, pass through the film, pass through the slit, are measured by the detector and give the stop time signal of the time of flight detection system; the time of flight detection system is used to obtain the time of flight spectrum through the time-amplitude conversion system, and realize the on-line analysis of the hydrogen and helium isotope content. The measurement is fast.

Description

Technical Field

[0001] This invention relates to the field of isotope detection technology, specifically to a time-of-flight-based online analysis device and method for hydrogen and helium isotopes. Background Technology

[0002] Hydrogen isotopes H-1, D-2, and T-3, and helium isotopes He-3 and He-4 are important nuclides for nuclear fusion, nuclear materials, and nuclear environment analysis. The development and application of online hydrogen and helium isotope analysis technology is of great significance to these studies. This invention is a time-of-flight-based online hydrogen and helium isotope spectrum analysis device.

[0003] The flight time (t) of an ion is determined by the following formula:

[0004]

[0005] Where d represents the flight distance, M represents the ion mass, and E represents the ion energy. It can be seen that the ion mass and energy are related to the ion's flight time. For ions with the same energy, different masses of nuclides have different flight times over the same distance, thus the time-of-flight method can be used to distinguish between nuclides of different masses. However, for the hydrogen-helium isotopes T-3 and He-3, their masses are very close, with a mass difference of less than one part in ten thousand, therefore the time-of-flight method cannot be directly used to analyze hydrogen-helium isotopes. Meanwhile... 3 He is a decay product of T, and materials containing tritium must contain He-3. Therefore, this is a challenge in hydrogen-helium isotope analysis. This invention proposes an analytical technique based on thin-film energy absorption combined with time-of-flight measurement. It utilizes the different energy losses of T-3 and He-3 after passing through the thin film, resulting in different flight times for the same distance, thus enabling the identification of T-3 and He-3. Simultaneously, H-1, D-2, and He-4, due to their different masses, can be analyzed using time-of-flight techniques. Therefore, time-of-flight technology can be used to analyze hydrogen-helium isotopes. Summary of the Invention

[0006] To address the problems existing in the prior art, the present invention aims to provide a time-of-flight-based online analysis device and method for hydrogen and helium isotopes, meeting the needs for rapid online analysis of hydrogen and helium isotopes in fields such as fusion reactor research. Based on the technological innovation of combining thin-film energy absorption and time-of-flight technology, the present invention solves the technical challenges of online analysis of hydrogen and helium isotopes, providing high-quality analytical devices and technologies for applications in the nuclear industry and the environment.

[0007] To achieve the above-mentioned objectives, the technical solution of the present invention is as follows:

[0008] A time-of-flight (FOF) based online hydrogen and helium isotope analysis device includes a cavity, a laser, a stage, extraction electrodes, a thin film, a slit, and a detector disposed within the cavity. A vacuum pump is connected externally to the cavity to maintain a vacuum within it. The laser uses pulsed laser light transmitted through an entrance window on the cavity to ionize hydrogen and helium isotopes on the stage into positive hydrogen ions and positive helium ions. The emission time of the pulsed laser is used as the start time signal of the time-of-flight detection system. The electric field between the stage and the extraction electrodes extracts and accelerates the positive hydrogen and helium ions to an appropriate energy. The positive hydrogen and helium ions pass through the thin film and the slit, where they are measured by the detector, which provides the stop time signal for the time-of-flight detection system. Using the time-of-flight detection system and a time-amplitude conversion system, a time-of-flight spectrum is obtained, enabling online analysis of the hydrogen and helium isotope content.

[0009] Furthermore, the stage, lead-out electrode, thin film, slit, and detector are arranged sequentially along the axis within the cavity.

[0010] Furthermore, the incident window is made of MgF2 or borosilicate glass, which can enhance the transmittance of the laser.

[0011] Furthermore, the test bench voltage is 48-50kV, and the lead-out electrode voltage is 0V.

[0012] Furthermore, a pre-extraction electrode in the shape of a grid is set close to the platform and the extraction electrode. The voltage of the pre-extraction electrode is 1kV lower than that of the platform. Positive ion extraction and focusing are achieved through voltage matching between the pre-extraction electrode and the extraction electrode.

[0013] Furthermore, if the hydrogen-helium isotopes are gases, they flow into the test bench through a quartz microporous tube.

[0014] Furthermore, the electric field between the test bench and the extraction electrode accelerates hydrogen and helium ions to energies of 48–50 keV.

[0015] Furthermore, the thin film is a silicon nitride thin film.

[0016] Furthermore, the silicon nitride film has a thickness of 30 nm.

[0017] Furthermore, the slit is circular with a diameter of 4–6 mm.

[0018] Furthermore, the distance between the detector and the thin film is 50 centimeters.

[0019] Furthermore, the detector is a microchannel plate.

[0020] Furthermore, the above-mentioned device is used to perform time-of-flight-based online analysis of hydrogen and helium isotopes, comprising the following steps:

[0021] Step 1: Place the sample containing hydrogen and helium isotopes on the stand;

[0022] Step 2: Use a pulsed laser to act on the sample containing hydrogen and helium isotopes and ionize the sample into positive hydrogen ions and positive helium ions. At the same time, use the pulsed laser emission time as the start time signal of the time-of-flight detection system.

[0023] Step 3: Use the electric field between the platform and the extraction electrode to extract hydrogen and helium ions and accelerate them to the appropriate energy.

[0024] Step 4: Use the thin film as an energy absorption membrane to allow hydrogen ions and helium ions to pass through the thin film;

[0025] Step 5: In order to eliminate stray particle interference and improve time resolution, hydrogen ions and helium ions are allowed to pass through the slit.

[0026] Step 6: The detector at an appropriate distance from the thin film measures and provides the stop time signal of the time-of-flight detection system;

[0027] Step 7: Using a time-of-flight detection system and a time-amplitude conversion system, a time-of-flight spectrum is obtained. By analyzing the different flight times of hydrogen and helium isotopes in the time-of-flight spectrum, online analysis of the hydrogen and helium isotope content is achieved.

[0028] Furthermore, in step 1, the solid sample containing hydrogen and helium isotopes is placed directly on the test bench.

[0029] Furthermore, in step 1, a gas sample containing hydrogen and helium isotopes flows into the test bench through a quartz microporous tube.

[0030] Furthermore, in step 1, the voltage of the test bench is 48-50kV.

[0031] Furthermore, in step 3, the voltage of the extraction electrode is 0V, and the hydrogen ions and helium ions are accelerated to an energy of 48-50 keV.

[0032] Furthermore, in step 4, the thin film is a silicon nitride thin film with a thickness of 30 nm.

[0033] Furthermore, in step 6, the distance between the detector and the thin film is 50 centimeters.

[0034] Furthermore, in step 6, the detector is a microchannel plate.

[0035] The beneficial effects of this invention are as follows:

[0036] 1. Simple structure: This detection equipment has a simple structure. Compared with other hydrogen and helium analysis equipment, this invention does not require expensive magnets and complex measurement systems. It can achieve analysis and measurement using only the time-of-flight method. At the same time, this method also has the advantage of being able to analyze both solid and gas samples.

[0037] 2. Rapid measurement: This invention enables online measurement, meeting the need for rapid online analysis of gas samples.

[0038] 3. In-situ analysis of solid samples: This technology, combined with laser ionization technology, can realize micro-area scanning analysis of solid samples, that is, it can determine the distribution at different locations and depths, and obtain the distribution information of hydrogen and helium isotopes in the sample at different locations and depths, thus meeting a wider range of applications. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of a time-of-flight-based online hydrogen-helium isotope analysis device. Detailed Implementation

[0040] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0041] This invention provides an online hydrogen and helium isotope analysis device based on time-of-flight, comprising a cavity, a laser, and a stage, extraction electrodes, a thin film, a slit, and a detector disposed within the cavity. A vacuum pump is connected externally to the cavity to maintain a vacuum within it. The laser uses pulsed laser light transmitted through an entrance window on the cavity to ionize hydrogen and helium isotopes on the stage into positive hydrogen ions and positive helium ions. The emission time of the pulsed laser is used as the start time signal of the time-of-flight detection system. The electric field between the stage and the extraction electrodes extracts and accelerates the positive hydrogen and helium ions to an appropriate energy. The positive hydrogen and helium ions pass through the thin film and the slit, where they are measured by the detector, which provides the stop time signal for the time-of-flight detection system. Using the time-of-flight detection system and a time-amplitude conversion system, a time-of-flight spectrum is obtained, enabling online analysis of the hydrogen and helium isotope content. The specific technical solution is as follows:

[0042] This invention discloses an online hydrogen and helium isotope analysis device based on time-of-flight, employing... Figure 1 The structure shown comprises a laser, a stage, lead-out electrodes, a thin film, a slit, and a detector, all housed within a vacuum chamber. An external vacuum pump maintains the system in a vacuum environment. The sample can be either a solid or a gaseous sample (for gaseous samples, gas is ejected through a microporous tube).

[0043] The test stand, lead-out electrodes, thin film, slit, and detector are arranged sequentially along the axis inside the cavity.

[0044] The sample containing hydrogen and helium isotopes is placed on a high-voltage stage with a voltage of approximately +50 kV. The laser uses pulsed laser light to act on the sample through an entrance window set on the cavity and ionizes the sample into positive hydrogen ions and positive helium ions. At the same time, the pulsed laser emission time is used as the start time signal of the time-of-flight detection system.

[0045] Using MgF2 or borosilicate glass as the laser's incident window can enhance the laser's transmittance.

[0046] The sample stand is an insulated stand that can withstand 50KV voltage. A grid-shaped pre-extraction electrode is provided close to the sample between the sample and the lead-out electrode. The voltage of the pre-extraction electrode is about 1KV lower than the positive high voltage of the stand.

[0047] The extraction electrode adopts a figure-eight structure, gradually approaching each other along the direction of ion movement. The voltage of the extraction electrode is set to 0V. Utilizing the potential difference between the high-voltage platform containing the hydrogen and helium isotope sample and the extraction electrode, the generated hydrogen and helium ions are extracted and accelerated to an energy of approximately 50 keV. By matching the voltage between the pre-extraction electrode and the extraction electrode, both accelerated extraction of ions and focusing of ions are achieved.

[0048] A silicon nitride thin film with excellent thickness uniformity was used as the energy absorption membrane. Considering the requirements for ion energy loss, a silicon nitride thin film thickness of 30 nm was adopted. Accelerated hydrogen and helium ions passed through the 30 nm thick silicon nitride thin film. Due to the different energy loss rates of hydrogen and helium isotopes penetrating the film, H, D, T, and helium isotopes He-3 and He-4 have different residual energies. Most critically, the energy difference between tritium and He-3 when passing through the silicon nitride thin film reaches 4 keV (He-3 has a residual energy of 42 keV, and T has a residual energy of 46 keV), resulting in an energy difference of approximately 9%. This energy difference is sufficient to ensure the resolution of tritium and He-3 using time-of-flight techniques. Since tritium has a higher residual energy than He-3, its flight time over the same distance is shorter than that of He-3. The different time-of-flight spectra of tritium and He-3 enable the resolution of tritium and He-3.

[0049] To effectively achieve ion identification and detector flexibility using time-of-flight technology, an ion flight distance of approximately 50 cm is used. To enhance time-of-flight identification capabilities, a microchannel plate with a fast rise time is employed for ion measurement. Hydrogen and helium ions, after passing through the thin film, are ultimately measured by the microchannel plate located 50 cm from the film, providing the stop time signal for the time-of-flight detection system. To eliminate stray particle interference and improve time resolution, a circular slit with a diameter of approximately 5 mm is placed in front of the microchannel detector.

[0050] A time-of-flight (TOF) detection system utilizes the start time signal triggered by a laser and the stop time signal measured by a microchannel plate detector. These two signals together form the TOF detection system. The measured start and stop time signals are fed into a hardware device capable of time-amplitude conversion (a time-amplitude converter). This device converts the ion's flight time into a voltage amplitude signal (i.e., the longer the flight time, the higher the voltage signal; they are directly proportional). Then, using amplitude data conversion hardware (ADC) and accompanying analysis software, the time-of-flight spectrum can be measured. Because H-1, H-2, H-3, He-3, etc., have different masses or energies, their flight times also differ, thus placing them at different positions on the time-of-flight spectrum. By observing the differences in the flight times of hydrogen and helium isotopes in the time-of-flight spectrum, online analysis of the hydrogen and helium isotope content in the sample can be achieved.

[0051] The time-of-flight-based online analysis method for hydrogen and helium isotopes includes the following steps:

[0052] Step 1: Place the sample containing hydrogen and helium isotopes on the stand;

[0053] Step 2: Use a pulsed laser to act on the sample containing hydrogen and helium isotopes and ionize the sample into positive hydrogen ions and positive helium ions. At the same time, use the pulsed laser emission time as the start time signal of the time-of-flight detection system.

[0054] Step 3: Use the electric field between the platform and the extraction electrode to extract hydrogen and helium ions and accelerate them to the appropriate energy.

[0055] Step 4: Use the thin film as an energy absorption membrane to allow hydrogen ions and helium ions to pass through the thin film;

[0056] Step 5: In order to eliminate stray particle interference and improve time resolution, hydrogen ions and helium ions are allowed to pass through the slit.

[0057] Step 6: The detector at an appropriate distance from the thin film measures and provides the stop time signal of the time-of-flight detection system;

[0058] Step 7: Using a time-of-flight detection system and a time-amplitude conversion system, a time-of-flight spectrum is obtained. By analyzing the different flight times of hydrogen and helium isotopes in the time-of-flight spectrum, online analysis of the hydrogen and helium isotope content is achieved.

[0059] Taking a time-of-flight device based on online analysis of hydrogen and helium isotopes as an example:

[0060] Example 1

[0061] The time-of-flight device for online analysis of hydrogen and helium isotopes in this embodiment employs, as follows: Figure 1 The structure shown consists of a laser, a stage, lead-out electrodes, a thin film, a slit, a detector, and other components. The entire system is housed within a vacuum chamber, and an external vacuum pump keeps the system in a vacuum environment.

[0062] Solid samples containing hydrogen and helium isotopes are placed on a high-voltage platform with a voltage of +48KV. The incident window is made of MgF2 glass. A pulsed laser is used to act on the sample and ionize it into positive hydrogen ions and positive helium ions. At the same time, the pulsed laser emission time is used as the start time signal of the time-of-flight detection system.

[0063] A pre-extraction electrode in the shape of a grid is provided close to the solid sample between the solid sample and the extraction electrode. The voltage of the pre-extraction electrode is set to 47KV.

[0064] The voltage of the extraction electrode is set to 0V. The hydrogen and helium ions generated by ionization are extracted and accelerated to an energy of 48keV by using the potential difference between the high-voltage platform containing the hydrogen and helium isotope sample and the extraction electrode.

[0065] A silicon nitride thin film with excellent thickness uniformity was used as the energy absorption film. Considering the requirements for ion energy loss, the thickness of the silicon nitride thin film used was 30 nm.

[0066] Accelerated hydrogen and helium ions pass through a 30 nm thick silicon nitride film.

[0067] The hydrogen and helium ions that pass through the membrane are ultimately measured by a microchannel plate 50 cm away from the membrane, which provides the stop time signal for the time-of-flight detection system. To eliminate stray particle interference and improve time resolution, a circular slit with a diameter of 4 mm is set in front of the microchannel detector.

[0068] A time-of-flight detection system is constructed using the start time signal of pulsed laser emission and the stop time signal of microchannel plate detector. The time-of-flight spectrum can be obtained through a time-amplitude conversion system. The different flight times of hydrogen and helium isotopes in the time-of-flight spectrum can be used to achieve online analysis of the hydrogen and helium isotope content in solid samples.

[0069] Example 2

[0070] The time-of-flight device for online analysis of hydrogen and helium isotopes in this embodiment employs, as follows: Figure 1 The structure shown consists of a laser, a stage, lead-out electrodes, a thin film, a slit, a detector, and other components. The entire system is housed within a vacuum chamber, and an external vacuum pump keeps the system in a vacuum environment.

[0071] A gas sample containing hydrogen and helium isotopes flows through a quartz microporous tube into a high-voltage stage with a voltage of +50KV. The incident window is made of borosilicate glass. A pulsed laser is used to act on the sample and ionize it into positive hydrogen ions and positive helium ions. At the same time, the pulsed laser emission time is used as the start time signal of the time-of-flight detection system.

[0072] A pre-extraction electrode in the shape of a grid is provided close to the gas sample between the gas sample and the extraction electrode. The voltage of the pre-extraction electrode is set to 49KV.

[0073] The voltage of the extraction electrode is set to 0V. The hydrogen and helium ions generated by ionization are extracted and accelerated to an energy of 50keV by using the potential difference between the high-voltage platform containing the hydrogen and helium isotope sample and the extraction electrode.

[0074] A silicon nitride thin film with excellent thickness uniformity was used as the energy absorption film. Considering the requirements for ion energy loss, the thickness of the silicon nitride thin film used was 30 nm.

[0075] Accelerated hydrogen and helium ions pass through a 30 nm thick silicon nitride film.

[0076] The hydrogen and helium ions that pass through the membrane are ultimately measured by a microchannel plate 50 cm away from the membrane, which provides the stop time signal for the time-of-flight detection system. To eliminate stray particle interference and improve time resolution, a circular slit with a diameter of 6 mm is set in front of the microchannel detector.

[0077] A time-of-flight detection system is constructed using the start time signal of pulsed laser emission and the stop time signal of microchannel plate detector. The time-of-flight spectrum can be obtained through a time-amplitude conversion system. Online analysis of the hydrogen and helium isotope content in a gas sample can be achieved by observing the difference in flight times of hydrogen and helium isotopes in the time-of-flight spectrum.

[0078] Taking the time-of-flight method for online analysis of hydrogen and helium isotopes as an example:

[0079] Example 3

[0080] Step 1: Place the solid sample containing hydrogen and helium isotopes on a high-voltage test bench with a voltage of approximately +48 kV.

[0081] Step 2: The incident window is made of MgF2 glass. A pulsed laser is used to act on the sample containing hydrogen and helium isotopes and ionize the sample into hydrogen positive ions and helium positive ions. At the same time, the pulsed laser emission time is used as the start time signal of the time-of-flight detection system.

[0082] Step 3: The voltage of the pre-extraction electrode is set to 47KV, and the voltage of the extraction electrode is set to 0V. The electric field between the high-voltage test bench and the extraction electrode is used to extract hydrogen ions and helium ions and accelerate them to an energy of 48KeV.

[0083] Step 4: Use a silicon nitride thin film as an energy absorption film. The thickness of the silicon nitride thin film is 30 nm, allowing hydrogen ions and helium ions to pass through the silicon nitride thin film.

[0084] Step 5: In order to eliminate stray particle interference and improve time resolution, hydrogen positive ions and helium positive ions are allowed to pass through a circular slit with a diameter of 4 mm.

[0085] Step 6: The stop time signal of the time-of-flight detection system is measured and given by a microchannel plate 50 cm away from the film;

[0086] Step 7: A time-of-flight detection system is constructed using the start time signal of the pulsed laser emission and the stop time signal of the microchannel plate detector. The time-of-flight spectrum can be obtained through the time-amplitude conversion system (time-amplitude converter). Online analysis of the hydrogen and helium isotope content in solid samples can be achieved by observing the difference in flight times of hydrogen and helium isotopes in the time-of-flight spectrum.

[0087] Example 4

[0088] Step 1: The gas sample containing hydrogen and helium isotopes is fed through a quartz microporous tube into a high-voltage test bench with a voltage of approximately +50 kV.

[0089] Step 2: The incident window is made of borosilicate glass. A pulsed laser is used to act on the sample containing hydrogen and helium isotopes and ionize the sample into positive hydrogen ions and positive helium ions. At the same time, the pulsed laser emission time is used as the start time signal of the time-of-flight detection system.

[0090] Step 3: The voltage of the pre-extraction electrode is set to 49KV, and the voltage of the extraction electrode is set to 0V. The electric field between the high-voltage test bench and the extraction electrode is used to extract hydrogen ions and helium ions and accelerate them to an energy of 50KeV.

[0091] Step 4: Use a silicon nitride thin film as an energy absorption film. The thickness of the silicon nitride thin film is 30 nm, allowing hydrogen ions and helium ions to pass through the silicon nitride thin film.

[0092] Step 5: In order to eliminate stray particle interference and improve time resolution, hydrogen positive ions and helium positive ions are allowed to pass through a circular slit with a diameter of 6 mm.

[0093] Step 6: The stop time signal of the time-of-flight detection system is measured and given by a microchannel plate 50 cm away from the film;

[0094] Step 7: A time-of-flight detection system is formed by using the start time signal of the pulsed laser emission and the stop time signal of the microchannel plate detector. The time-of-flight spectrum can be obtained by using the time-amplitude conversion system (time-amplitude converter). The different flight times of hydrogen and helium isotopes in the time-of-flight spectrum can be used to achieve online analysis of the hydrogen and helium isotope content in the gas sample.

[0095] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention is also intended to include these modifications and variations.

Claims

1. A time-of-flight-based online hydrogen and helium isotope analysis device, characterized in that: The system includes a cavity, a laser, and a stage, extraction electrodes, a thin film, a slit, and a detector arranged sequentially along an axis within the cavity. A vacuum pump is connected to the outside of the cavity to maintain a vacuum inside. The laser uses pulsed laser light transmitted through an entrance window on the cavity to ionize hydrogen and helium isotopes on the stage into positive hydrogen ions and positive helium ions. The emission time of the pulsed laser is used as the start time signal for the time-of-flight detection system. The electric field between the stage and the extraction electrodes extracts and accelerates the positive hydrogen and helium ions to energies of 48–50 keV. The positive hydrogen and helium ions pass through the thin film, which is a silicon nitride film with a thickness of 30 nm, causing energy loss in the ions. This results in an energy difference of 4 keV between tritium and He-3 ions passing through the silicon nitride film. The energy is measured by the detector after passing through the slit, providing the stop time signal for the time-of-flight detection system. Using the time-of-flight detection system and a time-amplitude conversion system, a time-of-flight spectrum is obtained, enabling online analysis of the hydrogen and helium isotope content.

2. The time-of-flight-based online hydrogen-helium isotope analysis device as described in claim 1, characterized in that: The incident window is made of MgF2 or borosilicate glass, which can enhance the transmittance of the laser.

3. The time-of-flight-based online hydrogen-helium isotope analysis device as described in claim 1, characterized in that: The test bench voltage is 48-50kV, and the lead-out electrode voltage is 0V.

4. The time-of-flight-based online hydrogen-helium isotope analysis device as described in claim 3, characterized in that: A pre-extraction electrode in the shape of a grid is set close to the platform and the extraction electrode. The voltage of the pre-extraction electrode is 1kV lower than the platform voltage. Positive ion extraction and focusing are achieved by voltage matching between the pre-extraction electrode and the extraction electrode.

5. The time-of-flight-based online hydrogen and helium isotope analysis device as described in claim 4, characterized in that: If the hydrogen and helium isotopes are gases, they flow into the test bench through a quartz microporous tube.

6. The time-of-flight-based online hydrogen-helium isotope analysis device as described in claim 1, characterized in that: The slit is circular with a diameter of 4–6 mm.

7. The time-of-flight-based online hydrogen-helium isotope analysis device as described in claim 1, characterized in that: The distance between the detector and the thin film is 50 centimeters.

8. The time-of-flight-based online hydrogen-helium isotope analysis device as described in claim 1, characterized in that: The detector is a microchannel plate.

9. A method for online analysis of hydrogen and helium isotopes based on time-of-flight using the apparatus described in any one of claims 1-8, characterized in that: Includes the following steps: Step 1: Place the sample containing hydrogen and helium isotopes on the stand; Step 2: Use a pulsed laser to act on the sample containing hydrogen and helium isotopes and ionize the sample into positive hydrogen ions and positive helium ions. At the same time, use the pulsed laser emission time as the start time signal of the time-of-flight detection system. Step 3: Use the electric field between the platform and the extraction electrode to extract hydrogen and helium ions and accelerate them to the appropriate energy. Step 4: Use the thin film as an energy absorption membrane to allow hydrogen ions and helium ions to pass through the thin film; Step 5: In order to eliminate stray particle interference and improve time resolution, hydrogen ions and helium ions are allowed to pass through the slit. Step 6: The detector at an appropriate distance from the thin film measures and provides the stop time signal of the time-of-flight detection system; Step 7: Using a time-of-flight detection system and a time-amplitude conversion system, a time-of-flight spectrum is obtained. By analyzing the different flight times of hydrogen and helium isotopes in the time-of-flight spectrum, online analysis of the hydrogen and helium isotope content is achieved.

10. The online hydrogen-helium isotope analysis method based on time-of-flight as described in claim 9, characterized in that: In step 1, the solid sample containing hydrogen and helium isotopes is placed directly on the stand.

11. The online hydrogen-helium isotope analysis method based on time-of-flight as described in claim 9, characterized in that: In step 1, a gas sample containing hydrogen and helium isotopes flows into the test bench through a quartz microporous tube.

12. The online hydrogen-helium isotope analysis method based on time-of-flight as described in claim 9, characterized in that: In step 1, the voltage of the test bench is 48-50kV.

13. The online hydrogen-helium isotope analysis method based on time-of-flight as described in claim 12, characterized in that: In step 3, the voltage of the extraction electrode is 0V, and the hydrogen ions and helium ions are accelerated to an energy of 48-50 keV.

14. The online hydrogen-helium isotope analysis method based on time-of-flight as described in claim 9, characterized in that: In step 4, the thin film is a silicon nitride thin film with a thickness of 30 nm.

15. The online hydrogen-helium isotope analysis method based on time-of-flight as described in claim 9, characterized in that: In step 6, the distance between the detector and the thin film is 50 centimeters.

16. The online hydrogen-helium isotope analysis method based on time-of-flight as described in claim 9, characterized in that: In step 6, the detector is a microchannel plate.

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