Laser ionization dynamic delay triggering system and method based on electronic feedback control

Abstract

The invention belongs to the technical field of mass spectrometry, and relates to a laser ionization dynamic delay triggering system and method based on electronic feedback control. A bias voltage is applied to a receiving plate to form a directional electric field, electrons generated in the ablation process are guided to move towards the receiving plate, a signal receiving module captures electronic signals in real time and transmits the electronic signals to a signal processing module, the signal processing module calculates particle kinetic energy parameters based on electronic signal characteristics, and the parameters directly reflect the spatio-temporal evolution state of particle plume; dynamically determining the optimal triggering time of the ionization laser; when laser energy is attenuated or a sample material is changed, an electronic signal acquired by a receiving plate synchronously changes, and an ionization laser triggering time sequence is immediately adjusted after processing, so that a second beam of laser is always matched with the optimal ionization moment of the particle plume, and a closed-loop control link of signal acquisition, parameter calculation and delay adjustment is formed; through real-time feedback of electronic signals, accurate perception of particle plume dynamic evolution and adaptive adjustment of delay time are realized.

Description

Technical Field

[0001] The present application belongs to the field of mass spectrometry technology, and more specifically, relates to a laser ionization dynamic delayed triggering system and method based on electronic feedback control. Background Art

[0002] LALI-TOF-MS (Laser Ablation–Laser Ionization–Time-of-Flight Mass Spectrometry) is a highly sensitive analytical method that combines laser ablation, laser ionization, and time-of-flight mass spectrometry. Its basic operating principles are as follows: The first short-pulse laser with specific parameters (usually nanosecond or picosecond pulse width, with a wavelength that can be selected in the ultraviolet, visible, or infrared bands depending on the sample characteristics) is focused onto the surface of the solid sample through a high-precision optical system. In an extremely short period of time, the laser energy is highly concentrated, causing the temperature of the local area of ​​the sample to rise sharply to above the ablation threshold of the material, triggering complex physical and chemical changes. The sample material undergoes a violent vaporization and atomization process, releasing a mixed material flow containing neutral atoms, molecules, and nano- to micron-sized particles, namely a particle plume. In this process, the ablation efficiency is closely related to the laser energy density, pulse frequency, and sample surface characteristics (such as roughness and thermal conductivity). The ablation behavior of different materials varies significantly. For example, the energy absorption efficiency and product distribution of metals and non-metallic materials during ablation are very different.

[0003] After laser ablation generates a particle plume, the system sets a critical delay time, after which a second laser beam (whose wavelength can be precisely tuned to the ionization characteristics of the target analyte to achieve resonant ionization or multiphoton ionization) irradiates the dynamically evolving particle plume. For resonant ionization, the photon energy of the second laser beam exactly matches the specific energy level transition of the target atom or molecule, thereby efficiently exciting the neutral particles to an ionized state. Multiphoton ionization, on the other hand, superimposes the energy of multiple photons to give particles enough energy to break free and form ions. This ionization process is extremely sensitive to the delay time, as the spatial distribution and composition of the particle plume change continuously over time. Only at the appropriate delay time can the interaction between the second laser beam and the particle plume achieve optimal ionization efficiency and generate a sufficient number of representative ions.

[0004] Traditional LALI systems generally adopt a pre-set fixed delay strategy, that is, a unified delay time parameter is used for different samples and experimental conditions. However, there are many dynamic changing factors in the actual analysis process, such as small fluctuations in laser energy (due to the stability limitation of the laser, energy fluctuations are inevitable), differences in thermal diffusivity of different materials (metallic materials have high thermal diffusivity and the particle plume diffuses quickly; non-metallic materials such as ceramics have low thermal diffusivity and the particle plume diffuses relatively slowly), and changes in the sample surface state (the sample surface is gradually eroded during the ablation process, resulting in changes in the ablation characteristics). These factors will cause the spatiotemporal evolution of the particle plume to be excessive. The fixed delay strategy cannot adapt to these changes in real time. When the delay time does not match the optimal ionization moment of the particle plume, the ionization efficiency will drop significantly. For example, if the delay time is too long, the particle plume may have diffused excessively, the ion concentration will be reduced, and some neutral particles may recombine or agglomerate, affecting the ionization effect. If the delay time is too short, the particle plume has not yet fully expanded, and the interaction between the laser and the particles is not sufficient, which will also lead to low ionization efficiency. This mismatch will directly lead to unstable detection signals and inaccurate analysis results. This problem is particularly prominent when analyzing trace substances or complex samples. Summary of the Invention

[0005] The present invention provides a laser ionization dynamic delay triggering system and method based on electronic feedback control, which aims to address the technical problem that the current traditional LALI system has deficiencies in delay strategy and feedback mechanism, making it difficult to achieve high-precision and high-sensitivity detection under complex and changing analytical conditions.

[0006] On the one hand, the present invention provides a laser ionization dynamic delayed trigger system based on electronic feedback control, comprising an ablation laser, an ionization laser, a focusing lens group, a mass analyzer, a deflection quadrupole and a sample detection platform, characterized in that a receiving plate is installed on the sample detection platform, and the receiving plate is used to place the detection sample; A grounding grid is provided between the receiving plate and the deflection quadrupole, and a pupil for the laser to pass through is provided on the grounding grid; A power supply is introduced to the receiving plate to apply a bias voltage, thereby forming an electric field to guide electrons to move toward the receiving plate; The receiving board is connected to a signal receiving module and a signal processing module; the signal receiving module receives electronic signals; the signal processing module calculates the particle kinetic energy based on the received electronic signals and determines the triggering time of the ionization laser.

[0007] The present invention applies a bias voltage to the receiving plate to form a directional electric field, guiding the electrons generated during the ablation process toward the receiving plate. The signal receiving module captures the electronic signals in real time and transmits them to the signal processing module. The latter calculates the particle kinetic energy parameters based on the electronic signal characteristics. These parameters directly reflect the spatiotemporal evolution of the particle plume (such as diffusion velocity and energy distribution). Dynamic changes in the plume caused by differences in thermal diffusivities of different materials and fluctuations in laser energy are accurately mapped to the particle kinetic energy signal. The signal processing module dynamically determines the optimal triggering time of the ionization laser based on this signal, replacing the traditional fixed delay strategy. When the laser energy decays or the sample material changes, the electronic signals collected by the receiving plate change synchronously. After processing, the ionization laser triggering timing is instantly adjusted to ensure that the second laser beam always matches the optimal ionization moment of the particle plume, forming a closed-loop control chain of "signal acquisition-parameter calculation-delay adjustment". This mechanism achieves accurate perception of the dynamic evolution of the particle plume and adaptive adjustment of the delay time through real-time feedback of the electronic signals, fundamentally solving the problem that fixed strategies cannot cope with complex variables. At the same time, it establishes a complete closed-loop adaptive control system, significantly improving the system's ionization efficiency and detection accuracy under dynamic conditions.

[0008] On the other hand, the present invention provides a laser ionization dynamic delay triggering method based on electronic feedback control, which uses the laser ionization dynamic delay triggering system based on electronic feedback control described in the present invention, including the following steps: The first laser beam emitted by the ablation laser generates the electron flight time, which is inverted to obtain the electron velocity. Based on the electron velocity, the flight velocity of the neutral particle is deduced through the central particle model, and the emission time of the ionization laser is dynamically calculated based on the flight velocity of the neutral particle.

[0009] Preferably, the ablation laser and the ionization laser both need to trigger the lamp pump signal and the Q switch signal and then trigger the laser after a predetermined delay; After the lamp pump signal is triggered, the Q switch signal is triggered after a predetermined delay.

[0010] Preferably, the lamp pump signals of the ablation laser and the ionization laser are triggered synchronously.

[0011] Preferably, after the ablation laser is emitted, electrons hit the receiving board, and the electronic signals are collected by the signal receiving module, and the electronic signals are transmitted to the signal processing module. The emission time of the ionization laser is calculated based on the signal processing module, and the time interval from the triggering of the lamp pump signal of the ionization laser to the triggering of the Q switch signal of the ionization laser is dynamically adjusted based on the calculated emission time of the ionization laser, thereby controlling the emission time of the ionization laser.

[0012] Preferably, based on historical data, the total time required for the ablation laser and ionization laser to be triggered from the lamp pump signal to the Q open signal and then to laser emission is obtained respectively, and the total time required for the ablation laser and ionization laser to be emitted is obtained respectively, and then the emission time of the current ionization laser is adjusted in combination with the historical flight speed of neutral particles.

[0013] Preferably, adjusting the emission time of the current ionization laser includes adjusting the lamp pump triggering time of the ionization laser or adjusting the time interval from the lamp pump triggering to the Q switch signal triggering of the ionization laser.

[0014] Preferably, the specific steps of calculating the emission time of the ionization laser are as follows: Record the time when the first laser beam of the ablation laser is emitted and the time when the electronic signal arrives, and based on this, calculate the time difference between the laser emission and the arrival of the electronic signal; Based on the obtained time difference, the electric field voltage and the electrode distance, the initial velocity of the electron is calculated; According to the kinetic energy formula, the initial kinetic energy of the electron is calculated based on the initial velocity of the electron and the mass of the electron; Based on the initial kinetic energy of the electrons and the mass of the particles, the flying speed of the particles is inferred from the relationship between kinetic energy and mass; According to the particle flight speed and the preset position of the laser ionization focus, a uniform linear motion model is used to divide the preset position of the laser ionization focus by the particle speed to obtain the time interval required for the emission of the ablation laser to the emission of the ionization laser.

[0015] The beneficial effects of the present invention include: the present invention applies a bias voltage to the receiving plate to form a directional electric field, guiding the electrons generated during the ablation process to move toward the receiving plate. The signal receiving module captures the electronic signal in real time and transmits it to the signal processing module. The latter calculates the particle kinetic energy parameters based on the electronic signal characteristics. The parameters directly reflect the spatiotemporal evolution state of the particle plume (such as diffusion velocity and energy distribution); the dynamic changes of the plume caused by differences in thermal diffusivities of different materials and fluctuations in laser energy are accurately mapped to the particle kinetic energy signal. The signal processing module can dynamically determine the optimal trigger time of the ionization laser based on this, replacing the traditional fixed delay strategy; when the laser energy decays or the sample material changes, the electronic signal collected by the receiving plate changes synchronously. After processing, the ionization laser trigger timing is immediately adjusted to ensure that the second laser beam always matches the optimal ionization moment of the particle plume, forming a closed-loop control link of "signal acquisition-parameter calculation-delay adjustment". This mechanism achieves accurate perception of the dynamic evolution of particle plumes and adaptive adjustment of delay time through real-time feedback of electronic signals, fundamentally solving the problem that fixed strategies are unable to cope with complex variables. At the same time, it builds a complete closed-loop adaptive control system, significantly improving the system's ionization efficiency and detection accuracy under dynamic conditions. In addition, the present invention is the first to realize the calculation of particle kinetic energy and the determination of the emission delay time of the ionization laser by electronic feedback. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0017] Figure 1 A schematic block diagram of a system provided by an embodiment of the present invention.

[0018] Figure 2 A schematic diagram of ion motion trajectories provided in an embodiment of the present invention.

[0019] Figure 3 A schematic diagram of electron motion trajectories provided by an embodiment of the present invention.

[0020] Figure 4 The trigger logic of the two lasers provided in embodiment 2 of the present invention.

[0021] Figure 5 A logic diagram of the triggering timeline of two lasers provided in an embodiment of the present invention.

[0022] Explanation of the accompanying symbols: 1. Sample detection platform; 2. Receiving plate; 3. Detection sample; 4. Power supply; 5. Signal receiving module; 6. Signal processing module; 7. Ablation laser; 8. Focusing lens group; 9. Ionization laser; 10. Mass analyzer; 11. Deflection quadrupole; 12. Grounding grid. DETAILED DESCRIPTION

[0023] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0024] Example 1 See also Figure 1 A laser ionization dynamic delayed trigger system based on electronic feedback control includes an ablation laser 7, an ionization laser 9, a focusing lens group 8, a mass analyzer 10, a deflection quadrupole 11, a grounding grid 12, and a sample detection platform 1. A receiving plate 2 is installed on the sample detection platform 1, and the receiving plate 2 is used to place a detection sample 3; The grounding grid 12 is provided between the receiving plate 2 and the deflection quadrupole 11, and a through hole for the laser to pass through is provided on the grounding grid 12; See also Figure 1 and Figure 3 , the receiving plate 2 is biased by a power supply 4, forming an electric field to guide the electrons to move toward the receiving plate 2; in this embodiment, the grounding grid 12 serves as the potential zero point of the entire circuit, providing a reference for the application of the bias voltage, so that a stable potential difference is formed between the receiving plate 2 and the surrounding environment; based on the stable potential difference, the electric field direction and signal strength are maintained, ensuring that the electrons can move along the preset path toward the receiving plate 2, and avoiding the disturbance of the electron trajectory caused by potential fluctuations; see Figure 3 As shown, through the combined action of the applied bias, the ablation laser 7 and the grounding grid 12, the electrons initially form a cone-shaped diffusion and move toward the grounding grid due to the explosion of the ablation laser 7. Under the action of the electric field, the electrons first decelerate and move toward the grounding grid 12, and then accelerate toward the receiving plate 2 until they hit the receiving plate 2.

[0025] See also Figure 1 and Figure 2 The receiving board 2 is connected to a signal receiving module 5 and a signal processing module 6; the signal receiving module 5 receives an electronic signal; the signal processing module 6 calculates the particle kinetic energy based on the received electronic signal and determines the triggering time of the ionization laser 9.

[0026] The present invention applies a bias voltage to the receiving plate 2 to form a directional electric field, guiding the electrons generated during the ablation process to move toward the receiving plate 2. The signal receiving module 5 captures the electronic signal in real time and transmits it to the signal processing module 6. The latter calculates the particle kinetic energy parameters based on the electronic signal characteristics. The parameters directly reflect the spatiotemporal evolution state of the particle plume (such as diffusion speed and energy distribution). Due to the differences in thermal diffusivities of different materials and the dynamic changes of the plume caused by laser energy fluctuations, they will be accurately mapped to the particle kinetic energy signal. Based on this, the signal processing module 6 can dynamically determine the optimal triggering time of the ionization laser 9, replacing the traditional fixed delay strategy. When the laser energy When the quantity decays or the sample material changes, the electronic signal collected by the receiving board 2 changes synchronously. After processing, the ionization laser trigger timing is adjusted in real time to ensure that the second laser beam always matches the optimal ionization moment of the particle plume, forming a closed-loop control link of "signal acquisition-parameter calculation-delay adjustment"; this mechanism realizes accurate perception of the dynamic evolution of the particle plume and adaptive adjustment of the delay time through real-time feedback of the electronic signal, fundamentally solving the problem that fixed strategies cannot cope with complex variables, and at the same time building a complete closed-loop adaptive control system, significantly improving the system's ionization efficiency and detection accuracy under dynamic conditions.

[0027] Example 2 A laser ionization dynamic delay triggering method based on electronic feedback control, using the laser ionization dynamic delay triggering system based on electronic feedback control described in the present invention, comprises the following steps: The first laser beam emitted by the ablation laser 7 generates an electron flight time, which is inverted to obtain the electron velocity. Based on the electron velocity, the flight velocity of the neutral particle is deduced through the central particle model, and the emission time of the ionization laser 9 is dynamically calculated based on the flight velocity of the neutral particle.

[0028] The specific steps of calculating the emission time of the ionization laser 9 are as follows: Record the time when the first laser beam is emitted by the ablation laser 7 and the time when the electronic signal arrives, and calculate the time difference between the laser emission and the arrival of the electronic signal based on this; Based on the obtained time difference, electric field voltage and electrode distance, the initial velocity of the electron is calculated: Where: Represents the time interval between the laser emission time and the arrival time of the electronic signal; represents the initial velocity of the electron; Indicates voltage; represents the mass of the electron; It represents the distance that electrons fly in the electric field; Indicates the amount of electron charge; It represents the distance that electrons fly in the electric field; According to the kinetic energy formula, the initial kinetic energy of the electron is calculated based on the initial velocity of the electron and the mass of the electron: Where: represents the initial kinetic energy of the electron; Based on the initial kinetic energy of the electron and the mass of the particle, the flight speed of the particle can be inferred from the relationship between kinetic energy and mass: Where: Indicates the theoretically calculated particle flight speed; represents the theoretically calculated collision kinetic energy; Indicates the theoretically calculated particle flight speed; These are empirical parameters obtained through experiments, and different matrices have different parameters.

[0029] According to the particle flight speed and the preset position of the laser ionization focus, a uniform linear motion model is used to divide the preset position of the laser ionization focus by the particle speed to obtain the time interval required for the emission of the ablation laser 7 to the emission of the ionization laser 9: Where: Indicates the optimal trigger delay time; Indicates the laser photoionization focus position.

[0030] After calculating the time interval between the emission of the ablation laser 7 and the emission of the ionization laser 9, the emission time of the ionization laser 9 can be adjusted by the following method. The specific steps are as follows: See also Figure 4 As shown, since the laser emission of the ablation laser 7 and the ionization laser 9 both need to be triggered by the lamp pump signal, the Q switch signal and then the laser emission; There is a predetermined delay between the triggering of the lamp pump signal and the triggering of the Q switch signal, which is at the level of hundreds of microseconds; and the delay from the triggering of the Q switch signal to the laser emission is at the level of nanoseconds. Therefore, in this embodiment, there is no need to consider the delay at the nanosecond level. We only need to adjust the delay between the triggering of the lamp pump signal and the triggering of the Q switch signal by calculating the time interval required for the emission of the ablation laser 7 to the emission of the ionization laser 9. The specific steps are as follows: Since both the ablation laser 7 and the ionization laser 9 involve delays at the microsecond level and nanosecond level, in this embodiment, the lamp pump signals of the ablation laser 7 and the ionization laser 9 are triggered synchronously; after the laser of the ablation laser 7 is generated, electrons hit the receiving board 2, and the electronic signals are collected by the signal receiving module 5 and transmitted to the signal processing module 6. Based on the signal processing module 6, the emission time of the ionization laser 9 is calculated, and the time interval from the triggering of the lamp pump signal of the ionization laser 9 to the triggering of the Q switch signal is dynamically adjusted based on the calculated emission time of the ionization laser 9, thereby controlling the emission time of the ionization laser 9.

[0031] It should be noted that the time from the triggering of the lamp pump signal to the emission of the ablation laser 7 is shorter than the time from the triggering of the lamp pump signal to the triggering of the Q switch signal of the ionization laser 9. After calculating the time interval required for the emission of the ablation laser 7 to the emission of the ionization laser 9, we need to dynamically adjust the time from the triggering of the lamp pump signal to the triggering of the Q switch signal based on this time interval. Figure 5 As shown, since the pump light signals of the ablation laser 7 and the ionization laser 9 are triggered synchronously, we only need to obtain the time interval (denoted as t1) required for the emission of the ablation laser 7 to the emission of the ionization laser 9, and use this time interval to adjust the time from the pump light signal of the ionization laser 9 to the triggering of the Q switch signal; for example: ; Wherein: t3 represents the adjustment amount of the delay from the lamp pump signal of the ionization laser 9 to the triggering of the Q switch signal; t2 represents the time interval from the Q switch signal to the emission of the ionization laser 9.

[0032] Two calculation methods are used above. Since the time interval from the Q switch signal to the emission of the ionization laser 9 is in the nanosecond level, we can ignore the factor in the hundreds of microsecond level; however, in order to more accurately control the emission time, it can also be taken into account.

[0033] It should be noted that t3 is the adjustment amount. Since we are emitting the lamp pump signals of the ionization laser 9 and the ablation laser 7 synchronously, that is, when the ablation laser 7 is emitted, the ionization laser 9 is in the time interval from the lamp pump triggering to the triggering of the Q switch signal. At this time, we only need to record the emission time node of the ablation laser 7, add t3 to this time node, and we get the triggering time node of the Q switch information of the ionization laser 9. Based on this, the dynamic adjustment of the laser emission of the ionization laser 9 is realized.

[0034] Example 3 Based on historical data, the total time required for the ablation laser 7 and ionization laser 9 to be triggered from the lamp pump signal to the Q open signal and then to laser emission is obtained respectively, and the total time required for the ablation laser 7 and ionization laser 9 to be emitted is obtained respectively, and then the emission time of the current ionization laser 9 is adjusted in combination with the historical flight speed of neutral particles.

[0035] It should be noted that this embodiment also uses synchronous triggering of the lamp pump signals of the ablation laser 7 and the ionization laser 9. Secondly, we use historical data to obtain the total time required for the ablation laser 7 and ionization laser 9 to fire. This provides the time difference between the two lasers. Combined with the time interval between the ablation laser 7 and the ionization laser 9 firing, we can derive the adjustment amount for the delay from the lamp pump signal of the ionization laser 9 to the triggering of the Q-switch signal. Based on the above, it can be seen that the difference between this embodiment 3 and embodiment 2 lies only in the method for obtaining the adjustment amount.

[0036] Example 4 In the technical solution of Example 3, we can not only control the emission time of the ionization laser 9 by adjusting the time interval from the lamp pump triggering of the ionization laser 9 to the triggering of the Q switch signal, but also adjust the emission time of the ionization laser 9 by adjusting the current lamp pump triggering time of the ionization laser 9. That is, the difference between Example 4 and Example 3 is that the lamp pump triggering time of the ionization laser 9 and the ablation laser 7 is asynchronous. Secondly, this embodiment also uses historical data to obtain the total time required for the two lasers from the lamp pump signal to laser emission. Based on the total time of the two lasers, we can obtain the emission time interval of the two lasers. Then, this emission time interval and the time interval required from the emission of the ablation laser 7 to the emission of the ionization laser 9 calculated historically are used to adjust the lamp pump triggering time of the current ionization laser 9. For Example 4, the average value of historical data can be taken to obtain the average time interval for calculation, that is, the total time of the two lasers can be used to obtain the emission time interval of the two lasers. Here, multiple sets of historical data can be used to take the average value, and the time interval required for the emission of the ablation laser 7 to the emission of the ionization laser 9 calculated historically can also be averaged using multiple sets of historical data.

[0037] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A laser ionization dynamic delayed trigger system based on electronic feedback control, comprising an ablation laser, an ionization laser, a focusing lens assembly, a mass analyzer, a deflection quadrupole, and a sample detection platform, characterized in that: The sample testing table is provided with a receiving plate for placing the testing sample; A grounding grid is provided between the receiving plate and the deflection quadrupole, and a pupil for the laser to pass through is provided on the grounding grid; A power supply is introduced to the receiving plate to apply a bias voltage, thereby forming an electric field to guide electrons to move toward the receiving plate; The receiving board is connected to a signal receiving module and a signal processing module; The signal receiving module receives the electronic signal; the signal processing module calculates the particle kinetic energy based on the received electronic signal and determines the triggering time of the ionization laser.

2. Laser ionization dynamic delay triggering method based on electronic feedback control, characterized in that: The laser ionization dynamic delayed trigger system based on electronic feedback control according to claim 1 comprises the following steps: The first laser beam emitted by the ablation laser generates the electron flight time, which is inverted to obtain the electron velocity. Based on the electron velocity, the flight velocity of the neutral particle is deduced through the central particle model, and the emission time of the ionization laser is dynamically calculated based on the flight velocity of the neutral particle.

3. The laser ionization dynamic delayed triggering method based on electronic feedback control according to claim 2, characterized in that: The ablation laser and the ionization laser both need to trigger the lamp pump signal and the Q switch signal and then trigger the laser after a predetermined delay; After the lamp pump signal is triggered, the Q switch signal is triggered after a predetermined delay.

4. The laser ionization dynamic delayed triggering method based on electronic feedback control according to claim 3, characterized in that: The lamp pump signals of the ablation laser and the ionization laser are triggered synchronously.

5. The laser ionization dynamic delayed triggering method based on electronic feedback control according to claim 4, characterized in that: After the ablation laser is emitted, electrons hit the receiving board, and the electronic signals are collected by the signal receiving module and transmitted to the signal processing module. The emission time of the ionization laser is calculated based on the signal processing module. Based on the calculated emission time of the ionization laser, the time interval from the triggering of the lamp pump signal of the ionization laser to the triggering of the Q switch signal of the ionization laser is dynamically adjusted, thereby controlling the emission time of the ionization laser.

6. The laser ionization dynamic delayed triggering method based on electronic feedback control according to claim 3, characterized in that: Based on historical data, the total time required for the ablation laser and ionization laser to be triggered from the lamp pump signal to the Q-open signal and then to laser emission is obtained respectively, and the total time required for the ablation laser and ionization laser to be emitted is obtained respectively. Then, the emission time of the current ionization laser is adjusted in combination with the historical flight speed of neutral particles.

7. The laser ionization dynamic delayed triggering method based on electronic feedback control according to claim 6, characterized in that: Adjusting the emission time of the current ionization laser includes adjusting the lamp pump triggering time of the ionization laser or adjusting the time interval from the lamp pump triggering to the Q switch signal triggering of the ionization laser.

8. The laser ionization dynamic delayed triggering method based on electronic feedback control according to any one of claims 2 to 7, characterized in that: The specific steps for calculating the emission time of the ionization laser are as follows: Record the time when the first laser beam of the ablation laser is emitted and the time when the electronic signal arrives, and based on this, calculate the time difference between the laser emission and the arrival of the electronic signal; Based on the obtained time difference, the electric field voltage and the electrode distance, the initial velocity of the electron is calculated; According to the kinetic energy formula, the initial kinetic energy of the electron is calculated based on the initial velocity of the electron and the mass of the electron; Based on the initial kinetic energy of the electrons and the mass of the particles, the flying speed of the particles is inferred from the relationship between kinetic energy and mass; According to the particle flight speed and the preset position of the laser ionization focus, a uniform linear motion model is used to divide the preset position of the laser ionization focus by the particle speed to obtain the time interval required for the emission of the ablation laser to the emission of the ionization laser.

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