High-sensitivity X-ray detection method and device based on laser ionization gas

Abstract

A high-sensitivity X-ray detection method and device based on laser ionized gas generates X-ray signals through laser ionized gas. Lasers and low-energy rays are filtered out using a metal filter membrane. Electrons are deflected through small holes and sintered NdFeB magnets to filter out fluorescent X-rays generated by electron collisions (at least weakened by one order of magnitude), thereby improving signal contrast. Finally, weak X-ray signals are detected by an X-ray silicon drift detector. At the same time, by changing laser parameters, gas types or the angle of the X-ray detector, the present invention can also be used for angular distribution detection of weak X-ray signals.

Description

Technical Field

[0001] The present invention belongs to the field of X-ray technology, and specifically is a high-sensitivity X-ray detection method and device based on laser ionization gas, which can filter signals in the X-ray band and improve the signal-to-noise ratio, thereby realizing the detection of weak high-order harmonic signals in the signal. Background Art

[0002] Real-time observation of electron dynamics within atoms requires ultrashort time spans from femtoseconds to attoseconds, which is equivalent to a photon energy span of 0.1-10KeV (KeV, kiloelectronvolts, electronvolts are energy units). At the same time, pump detection in ultrafast dynamics requires extreme ultraviolet (XUV) and X-ray attosecond light sources. High-order harmonics are currently an important coherent light source, but the spectra of most high-order harmonic light sources are limited to the XUV band. X-rays can obtain the internal states of atomic and molecular motion, which requires photon energy to be extended to about 500eV or even above 1KeV.

[0003] There are currently two methods for obtaining X-ray band high-order harmonic spectra. The first is to apply mid-infrared femtosecond laser to ultra-high pressure gas, and obtain a spectrum with photon energy exceeding 1.6KeV through a phase matching process (TenioPopmintchev et al., Science 336, 1287 (2012)). The second is to increase the intensity of the incident laser, completely ionize the gas, and use ions to generate high-order harmonics (DDAClarke et al., Phys. Rev. A 97, 023413 (2018); Dimitar Popmintchev et.al., Science 350, 6265 (2015)). The energy of the photon may also reach 1KeV and above. However, the second method is still in the theoretical stage, and there is no experimental proof that photon energy of 1KeV and above can be generated through the ion high-order harmonic mechanism. When laser ionization of gas generates X-ray signals, the signal may contain both fluorescence spectrum and high-order harmonic spectrum. When the energy reaches the KeV band, the high-order harmonic spectrum signal is very weak, and the collision of ionized electrons with matter (especially matter containing metal elements) will produce corresponding X-ray fluorescence radiation, which will interfere with the high-order harmonic signal and even annihilate the high-order harmonic signal generated by ions. This makes it difficult to explore the mechanism of high-order harmonic generation by ions in experiments. Summary of the invention

[0004] The present invention mainly utilizes laser ionization gas to generate X-ray signals, and designs an electron deflection device at the same time to eliminate the influence of fluorescent X-rays generated by scattering collision of ionized electrons, improve the spectral signal-to-noise ratio, and experimentally realize the detection of high-sensitivity high-order harmonic signals in the X-ray band.

[0005] The technical solution of the present invention:

[0006] A high-sensitivity X-ray detection method based on laser ionization of gas, characterized in that X-ray signals are generated by laser ionization of gas. The intensity at the laser focus is 2×10 16 W / cm 2 When the gas acts, the gas pressure exceeds 1Mpa, and the mechanism of the generated X-ray band signal is the generation of high-order harmonics of gas ions. After the signal is filtered, the noise such as fluorescent X-rays is filtered out, and a weak signal in the X-ray band is obtained.

[0007] A high-sensitivity X-ray device based on laser ionized gas, characterized in that it includes a half-wave plate, a quarter-wave plate, an X-ray generating cavity with an input window and a computer, as well as a plano-convex convergent lens, a gas nozzle system, an electronic deflection system, and an X-ray detection system arranged in the X-ray generating cavity; along the propagation direction of the incident femtosecond laser, the half-wave plate, the quarter-wave plate, the input window, the plano-convex convergent lens, the electronic deflection system, and a silicon drift detector (SDD) are arranged in sequence; the gas nozzle system is used to eject gas and react with the laser to generate an X-ray signal, which is transmitted to the electronic deflection system; the electronic deflection system is used to filter out laser and low-energy rays, and deflect electrons, thereby filtering out fluorescent X-rays generated by electron collisions; the X-ray detection system is used to detect the generated weak X-ray signals. The computer is connected to the gas injection system and the silicon drift detector respectively.

[0008] The gas nozzle system comprises: a gas nozzle, a gas nozzle control system, a three-dimensional electric translation stage and a bracket; the gas nozzle is fixedly connected to the bracket, the bracket is connected to the three-dimensional electric translation stage, and the gas nozzle control system adjusts the working parameters of the gas nozzle;

[0009] The gas nozzle control system includes a delay controller, an oscilloscope and a gas nozzle controller; the delay controller input port B receives the +5V electrical signal A emitted by the laser amplifier, and then generates an electrical signal with adjustable delay and outputs it from port C, and simultaneously inputs the signal to the gas nozzle controller port F and the oscilloscope input port D, the oscilloscope simultaneously inputs the laser electrical signal to port E and the electrical signal generated by the delay controller to port D, and by observing the oscilloscope, the delay of the delay controller output signal C is adjusted to adjust the time difference between the two signals, and when the gas nozzle controller receives the electrical signal F input by the delay controller, it outputs an electrical signal H from its port G to control the operation of the gas nozzle.

[0010] The three-dimensional electric translation stage can realize the adjustment of XYZ directions in three-dimensional space and is controlled by a computer.

[0011] The electronic deflection system comprises an electronic deflection device, a bracket and a metal filter membrane bracket. The electronic deflection device comprises a front surface small hole, a rear surface small hole and two side magnets; the front surface small hole is used to block noise signals and part of electrons with a large divergence angle, and the rear surface small hole is used to block part of the fundamental frequency laser beam; the electronic deflection device is connected to the bracket, and the long slot large through hole and small through hole structure in the bracket allow the electronic deflection device and the bracket to adjust their relative positions when connected; the rear end of the electronic deflection device has three grooves; the metal filter membrane is plated on the metal filter membrane bracket, and the filter membrane bracket is placed in the groove to block the incident femtosecond laser and filter low-energy signals;

[0012] The electron deflection device is made of polyamide fiber, and the main constituent elements are C, H, O, and N.

[0013] The X-ray detection system comprises: an SDD, a support rod, a base and an electric rotating table; the SDD is supported by the support rod and the base, and the base is connected to the electric rotating table;

[0014] The electric rotating table can be centered along the laser propagation direction, allowing 150° clockwise rotation and 150° counterclockwise rotation, with a repeat positioning accuracy of ±0.001°, to detect the X-ray angular distribution (horizontal spatial distribution); the electric rotating table is controlled by a computer.

[0015] The front and rear surfaces of the half-wave plate are coated with a 0° anti-reflection film for rotating the polarization plane of linear polarized light.

[0016] The front and rear surfaces of the 1 / 4 wave plate are coated with 0° anti-reflection films for adjusting the polarization state of the incident femtosecond laser.

[0017] The X-ray generating chamber comprises three mechanical dry pumps, one Roots vacuum pump, and three molecular pumps. Each molecular pump is equipped with a corresponding fore pump, which can ensure a vacuum degree of 10 -4 Pa or above, the vacuum degree can be guaranteed to be 10 -3 Pa or above.

[0018] The front and rear surfaces of the plano-convex converging lens are coated with a 0° anti-reflection film.

[0019] The magnet is composed of two sintered NdFeB strong magnets, with a single surface magnetic force of 5080 Gauss (Gauss, a unit of magnetic field strength) and a residual magnetism of 14700 Gauss. The purpose is to construct a strong magnetic field to deflect electrons, so that the electrons hit the inner wall of the deflection device and prevent the electrons from hitting metal products, metal filters and SDD. Improve the signal-to-noise ratio of X-ray (mainly 1KeV and above) signals

[0020] The metal filter membrane is usually an aluminum membrane or a zirconium membrane, and the thickness ranges from 0.15 μm to 10 μm. By adjusting the thickness of the filter membrane, the counting rate of the detector when collecting X-ray signals is controlled to be lower than 0.05 photon counts / second / Hz.

[0021] The main working process of the present invention is:

[0022] 1. Align the center axis of the incident femtosecond laser with the center axis of the electron deflection device and SDD

[0023] 2. The gas nozzle is brought close to the laser focus by controlling the electric translation stage to optimize the X-ray signal intensity.

[0024] 3. The laser operating frequency and the gas nozzle operating frequency are matched through the gas nozzle control system to make the generated X-ray signal the strongest.

[0025] 4. The rotation of the SDD is controlled by an electric rotation stage to detect the angular distribution of X-rays.

[0026] 5. Use a computer to save and process the X-ray signal data collected by the software.

[0027] Advantages of the present invention:

[0028] 1. Use laser to ionize gas to generate X-ray signals. The metal filter blocks the incident fundamental frequency laser and removes low-energy ray signals. At the same time, the magnetic field deflects electrons to remove high-energy fluorescent X-rays (photon energy greater than 1 KeV) generated by the collision of electrons with metal materials, which can reduce the intensity of fluorescent X-rays by at least one order of magnitude. The whole device can achieve high-sensitivity detection of X-ray signals.

[0029] 2. The electronic deflection device has a compact structure and a small size. It integrates the pinhole aperture, magnet, and metal filter membrane bracket on the same structure and is connected to the SDD. It can move synchronously with the detector to realize the detection of the angular distribution of X-ray signals (horizontal spatial distribution).

[0030] 3. It can realize quick replacement of magnets of different strengths and different metal filter membranes, saving installation and adjustment time.

[0031] 4. The system can be directly used for experimental exploration of a variety of different physical mechanisms, such as ion high-harmonic X-ray generation, characteristic X-ray spectrum detection, etc., by using different gases and changing the parameters of the experimental laser. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of the structure of a high-sensitivity X-ray detection device based on laser ionization gas in the present invention.

[0033] Figure 2This is the working diagram of the gas nozzle control system

[0034] Figure 3 This is the relationship diagram between the electron deflection device and the bracket

[0035] Figure 4 This is a side view and cross-sectional view of the electron deflection device structure.

[0036] Figure 5 This is the side view and cross-sectional view of the electron deflection device structure from another direction

[0037] Figure 6 This is a schematic diagram of the structure of the metal filter support in the electron deflection device.

[0038] Figure 7 This is a schematic diagram of the structure of the electron deflection device connecting bracket

[0039] Figure 8 The spectrum includes and does not include the electronic deflection system.

[0040] Fig. 9 This is the high-order harmonic spectrum produced by krypton gas

[0041] Fig.10 The spectrum of different laser polarization states DETAILED DESCRIPTION

[0042] The present invention is further described below in conjunction with the accompanying drawings.

[0043] See also Figure 1 , Figure 1 The present invention is a high-sensitivity X-ray detection method and device structure schematic diagram based on laser ionization gas. As can be seen from the figure, the present invention includes a half-wave plate 2, a quarter-wave plate 3 and an X-ray generating cavity 5 in the propagation direction of the incident femtosecond laser 1. The cavity 5 has an input window 4. The vacuum degree of the X-ray generating cavity 5 reaches 10 -4 Pa or more, the vacuum degree of the chamber 5 can reach 10 -3 Pa or above. In the generating cavity 5, along the direction of laser propagation, there are plano-convex focusing lens 6, gas nozzle 7, electronic deflection system 20, and SDD10. The gas nozzle 7 is stably connected to the bracket 12 that fixes it, and the bracket 12 is connected to the three-dimensional electric translation stage 11, and the three-dimensional electric translation stage 11 is controlled by a computer 16. The gas nozzle control system 17 adjusts the working parameters of the gas nozzle 7. SDD10 is supported by a support rod 15 and a base 14, and the base 14 is connected to an electric rotating stage 13 that can rotate 360 ​​degrees horizontally, and the center of the left end of the base 14 completely overlaps with the laser focus in the vacuum in the vertical direction, ensuring that when SDD10 rotates with the electric translation stage 13, it is centered on the laser focus. The electric rotating stage 13 is controlled by a computer 16.

[0044] After passing through the half-wave plate 2 and the quarter-wave plate 3, the femtosecond laser 1 generates incident light of specific polarization, and then passes through the window 4 to enter the X-ray generating cavity. It is focused at the gas outlet through the plano-convex converging lens 6, and the gas outlet is close to the laser focus. The generated X-ray signal and the femtosecond incident light pass through the small holes 81 and 82 along the optical axis. When the high-energy electrons pass through the magnetic field generated by the magnet 83, they are deflected and hit the inner wall of the electron deflection device 8. After passing through the metal filter membrane 85, the incident femtosecond laser and the specific band signal are filtered out. Finally, the X-ray signal is captured by the SDD10, and the data is saved by the acquisition software in the computer 16.

[0045] The front and rear surfaces of the half-wave plate 2 are coated with a 0° anti-reflection film for rotating the polarization plane of linear polarized light.

[0046] The front and rear surfaces of the 1 / 4 wave plate 3 are coated with a 0° anti-reflection film for adjusting the polarization state of the incident femtosecond laser.

[0047] The high-order harmonic generation chamber 5 includes three mechanical dry pumps, a Roots vacuum pump, and three molecular pumps, each of which is equipped with a corresponding front pump. The vacuum degree can be guaranteed to be 10 -4 Pa or above, the vacuum degree can be guaranteed to be 10 -3 Pa or above.

[0048] The front and rear surfaces of the plano-convex converging lens 6 are coated with a 0° anti-reflection film.

[0049] The three-dimensional electric translation stage 11 can realize the adjustment of the XYZ directions in three-dimensional space with an adjustment accuracy of 2.5 μm, allowing fine adjustment of the laser focus position.

[0050] The electric rotating table 13 can be rotated 150° clockwise and 150° counterclockwise with the laser propagation direction as the center, with a repeat positioning accuracy of ±0.001°, so as to detect the angular distribution of X-rays (horizontal spatial distribution).

[0051] The gas nozzle control system 17 is composed of three parts. Figure 2, respectively, are delay controller 171, oscilloscope 172, and gas nozzle controller 173. The input port B of the delay controller 171 receives the +5V electrical signal A emitted by the laser amplifier, and then generates an electrical signal with adjustable delay and outputs it from port C, and simultaneously inputs this signal to port F of the gas nozzle controller 173 and port D of the oscilloscope 172. The oscilloscope 172 simultaneously inputs the laser electrical signal to port E and the electrical signal generated by the delay controller 171 to port D. By observing the oscilloscope 172, the delay of the output signal C of the delay controller 171 is adjusted to adjust the time difference between the two signals. When the gas nozzle controller 173 receives the electrical signal F input by the delay controller 171, it outputs the electrical signal H from its port G to control the operation of the gas nozzle 7.

[0052] The electronic deflection system 20 is composed of three parts, see Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 . They are respectively an electron deflection device 8, a bracket 9, and a metal filter membrane bracket 84. The electron deflection device 8 includes a front surface small hole 81 and a rear surface small hole 82. The front surface small hole 81 is used to block noise signals and part of the electrons with a large divergence angle, and the rear surface small hole 82 is used to block the fundamental frequency laser beam, as well as two side magnets 83. The electron deflection device 8 is connected to the bracket 9 by 4 M4 and 4 M3 vacuum compatible screws to ensure the stability of the connection. The long slot large through hole 91 and the small through hole 92 structure in the bracket 9 allow the relative position of the electron deflection device 8 and the bracket 9 to be adjusted when connected, which is convenient for adjustment in accordance with actual installation. There are three grooves 84 at the rear end of the electron deflection device 8, which is convenient for installing the metal filter membrane bracket. The metal filter membrane is plated on the metal filter membrane bracket 85, and then the filter membrane bracket 85 is placed in the groove 84, which is used to block the incident femtosecond laser and filter low-energy signals in the experiment. The type of metal filter membrane is selected according to the specific experiment. The electron deflection system 20 is connected and fixed to the SDD via the long slot structure 94 in the bracket 9 .

[0053] The electron deflection device 8 is made of polyamide fiber (nylon, model HP 3D PA 12), and its main constituent elements are C, H, O, and N.

[0054] The magnet 83 is composed of two sintered NdFeB strong magnets, with a single surface magnetic force of 5080 Gauss and a residual magnetism of 14700 Gauss. The purpose is to construct a strong magnetic field to deflect electrons, so that stray electrons hit the inner wall and prevent electrons from hitting metal products, metal filters and detectors, thereby improving the signal-to-noise ratio of X-ray signals (mainly 1 KeV and above).

[0055] The metal filter membrane support 85 has a metal filter membrane on the surface, which is usually an aluminum membrane or a zirconium membrane. The thickness of the metal membrane ranges from 0.15 μm to 10 μm. By adjusting the thickness of the filter membrane, the counting rate is controlled to be lower than 0.05 photon counts / second / Hz.

[0056] The present invention utilizes the magnetic field generated by the magnet in the electron deflection device to deflect the electrons moving in the magnetic field, and finally hit the inner wall made of nylon (polyamide fiber), eliminating the fluorescent X-rays with energy greater than 1KeV caused by the collision between the electrons and the metal material. The signal passes through the metal filter membrane to filter the low-energy rays, and at the same time controls the SDD count rate to be lower than 0.05 photon counts / second / Hz. Thus, high-sensitivity detection of weak high-order harmonic signals in the X-ray band generated by laser ionized gas is achieved.

[0057] The following is a detailed description of a specific embodiment of the present invention:

[0058] Embodiment 1:

[0059] The infrared femtosecond laser is an incident femtosecond laser 1 with a central wavelength of 1450nm, a pulse width of 60fs, a repetition frequency of 20Hz, and an energy output of 7mJ. After being focused by a half-wave plate 2, a quarter-wave plate 3, an incident window 4, and a plano-convex focusing lens 6 with a focal length of 100mm, the effective light intensity at the focus is about 1.2×10 16 W / cm 2 The laser focus is close to the gas outlet of the gas nozzle 7, which is filled with the first inert gas (He) with a gas pressure of 0.8 MPa. During operation, the single jet time of the gas nozzle 7 is set to 300 μs by the gas nozzle control system 17, the operating frequency is 20 Hz, and the gas nozzle 7 is set to match the laser operating frequency by the delay controller 171.

[0060] The laser and the signal are coaxially transmitted to the electronic deflection system 20, passing through the center of the front surface hole 81 in the electronic deflection device 8, and then passing through the deflection magnetic field formed by two magnets 83. The electrons are deflected and hit the inner wall of the electronic deflection device 8, passing through the rear surface hole 82, and the filter holder 85 coated with a 150nm thick aluminum film, and finally the spectrum signal is collected by SDD10 (the collection time is 1800s), and the data is saved by computer 16. The obtained signal spectrum is Figure 8 As shown in curve A.

[0061] Embodiment 2:

[0062] Repeat the steps in the above embodiment 1, except that the electron deflection system 8 is removed. A support 85 coated with a 150 nm thick aluminum film is placed in front of the SDD 10. The signal spectrum obtained is: Figure 8 As shown in curve B.

[0063] from Figure 8It can be seen from the comparison between curve A and curve B that the electron deflection system 20 can effectively reduce the fluorescent X-ray signal (photon energy 1 KeV to 5 KeV), and the fluorescent X-ray signal is reduced by at least one order of magnitude.

[0064] Embodiment 3:

[0065] Using the high-sensitivity X-ray detection method and device of the present invention, the steps in the above-mentioned embodiment 1 are repeated, and the gas in the gas nozzle 7 is replaced with the fourth inert gas (Kr), and the gas pressure is set to 0.1 MPa. The metal filter membrane support 85 is replaced with an 8 μm thick aluminum film. The SDD10 acquisition time is set to 1200 s. Using the present invention, the Kr ion X-ray high-order harmonic spectrum is obtained, and the spectrum diagram is shown in Fig. 9 The polarization state (linear polarization and circular polarization) of the incident femtosecond laser 1 is changed by the quarter wave plate 3, and the X-ray spectra obtained under different polarization states are collected, see Fig.10 By comparing the signal curve under linear polarization (curve C) and the signal curve under circular polarization (curve D), it can be judged through the spectra under different polarizations that the X-rays in spectrum 9 are high-order harmonic signals generated by Kr ions.

Claims

1. A highly sensitive X-ray device based on laser ionization of gas, characterized in that: The invention comprises a half-wave plate (2), a quarter-wave plate (3), an X-ray generating cavity (5) having an input window (4), and a computer (16), as well as a plano-convex converging lens (6), a gas nozzle system, an electronic deflection system (20), and an X-ray detection system arranged in the X-ray generating cavity (5); along the propagation direction of the incident femtosecond laser (1), the half-wave plate (2), the quarter-wave plate (3), the input window (4), the plano-convex converging lens (6), the electronic deflection system (20), and the silicon drift detector (10) are arranged in sequence; The gas nozzle system is used to eject gas and interact with the laser to generate X-ray signals, which are transmitted to the electronic deflection system (20); The electron deflection system (20) is used to filter out laser light and low-energy rays, and to deflect electrons, thereby filtering out fluorescent X-rays generated by electron collisions; The X-ray detection system is used to detect the generated weak X-ray signals; The computer (16) is connected to the gas nozzle system and the silicon drift detector (10) respectively; The electronic deflection system (20) comprises an electronic deflection device (8), a bracket (9) and a metal filter membrane bracket (85), wherein the electronic deflection device (8) comprises a front surface small hole (81), a rear surface small hole (82), and two side magnets (83); the front surface small hole (81) is used to block noise signals and part of electrons with a large divergence angle, and the rear surface small hole (82) is used to block part of the fundamental frequency laser beam; the electronic deflection device (8) is connected to the bracket (9), and the long groove large through hole (91) and the small through hole (92) structure in the bracket (9) allow the electronic deflection device (8) and the bracket (9) to adjust the relative position when they are connected; the rear end of the electronic deflection device (8) is provided with three grooves (84); the metal filter membrane is plated on the metal filter membrane bracket (85), and the filter membrane bracket (85) is then placed in the groove (84) to block the incident femtosecond laser and filter low-energy signals.

2. The high-sensitivity X-ray device based on laser ionization of gas according to claim 1, characterized in that: The gas nozzle system comprises: a gas nozzle (7), a gas nozzle control system (17), a three-dimensional electric translation platform (11) and a bracket (12); the gas nozzle (7) is fixedly connected to the bracket (12), the bracket (12) is connected to the three-dimensional electric translation platform (11), and the gas nozzle control system (17) adjusts the working parameters of the gas nozzle (7); The gas nozzle control system (17) comprises a delay controller (171), an oscilloscope (172) and a gas nozzle controller (173); the input port B of the delay controller (171) receives a +5V electrical signal A emitted by a laser amplifier, and then generates an electrical signal with adjustable delay and outputs it from port C, and simultaneously inputs the signal to port F of the gas nozzle controller (173) and port D of the oscilloscope (172); the oscilloscope (172) simultaneously inputs the laser electrical signal to port E and the electrical signal generated by the delay controller (171) to port D, and by observing the oscilloscope (172), the delay of the output signal C of the delay controller (171) is adjusted to adjust the time difference between the two signals; when the gas nozzle controller (173) receives the electrical signal F input by the delay controller (171), it outputs an electrical signal H from its port G to control the operation of the gas nozzle (7); The three-dimensional electric translation stage (11) can realize adjustment in the XYZ directions in three-dimensional space and is controlled by a computer (16).

3. The high-sensitivity X-ray device based on laser ionization of gas according to claim 1, characterized in that: The X-ray detection system comprises: a silicon drift detector (10), a support rod (15), a base (14) and an electric rotating table (13); the silicon drift detector (10) is supported by the support rod (15) and the base (14), and the base (14) is connected to the electric rotating table (13); The electric rotating table (13) can realize the repeated positioning accuracy of ±0.001° along the laser propagation direction, and realize the detection of the spatial distribution of the X-ray angle in the horizontal direction; the electric rotating table (13) is controlled by a computer (16).

4. The high-sensitivity X-ray device based on laser ionization of gas according to claim 1, characterized in that: The front and rear surfaces of the half-wave plate (2) are coated with a 0° anti-reflection film, which is used to rotate the polarization plane of linear polarized light.

5. The high-sensitivity X-ray device based on laser ionization of gas according to claim 1, characterized in that: The front and rear surfaces of the 1 / 4 wave plate (3) are coated with a 0° anti-reflection film, which is used to adjust the polarization state of the incident femtosecond laser.

6. The high-sensitivity X-ray device based on laser ionization of gas according to claim 1, characterized in that: The X-ray generating chamber (5) comprises three mechanical dry pumps, a Roots vacuum pump, and three molecular pumps. Each molecular pump is equipped with a corresponding fore pump, which can ensure a vacuum degree of 10 -4 Pa or above, the vacuum degree can be guaranteed to be 10 -3 Pa or above.

7. The high-sensitivity X-ray device based on laser ionization of gas according to claim 1, characterized in that: The front and rear surfaces of the plano-convex converging lens (6) are coated with a 0° anti-reflection film.

8. A detection method using the high-sensitivity X-ray device based on laser ionization of gas as claimed in claim 1, characterized in that The laser ionizes the gas to generate X-ray signals with an intensity of 2×10 16 W / cm 2 When the gas acts, the gas pressure exceeds 1Mpa, and the mechanism of the generated X-ray band signal is the generation of high-order harmonics of gas ions. After the signal is filtered, the fluorescent X-ray noise is filtered out and a weak signal in the X-ray band is obtained.

Images