A polycyclic time-of-flight mass spectrometer

Abstract

This invention discloses a ring-type time-of-flight mass spectrometer, which includes at least one electron source assembly. The electron source assembly includes a repulsion plate capable of repelling electrons. The surface of the repulsion plate is arc-shaped, and a filament is disposed on the concave side of the repulsion plate. This ring-type time-of-flight mass spectrometer improves the detection accuracy of the device.

Description

Technical Field

[0001] This invention relates to the field of detection instrument technology, and in particular to a polycyclic time-of-flight mass spectrometer. Background Technology

[0002] Mass spectrometry is an important branch of mass spectrometry detection technology. Time-of-flight mass spectrometry is a mass spectrometer that establishes a mass spectrum by having ions arrive at the detector at different times according to different mass-to-charge ratios in a vacuum field-free region at a certain distance.

[0003] A time-of-flight mass spectrometer includes an ion source, an acceleration space, a flight space, and a detector. The sample is placed in the ion source, which contains a filament that generates electrons to ionize the sample. The ions are accelerated in the acceleration space. Due to the different masses of the ions, they are emitted at different velocities in the same electric field. After flying in the flight space, the ions have a path difference, which is then detected by the detector to obtain their mass spectrum.

[0004] The inventors discovered that the filament produces a limited number of electrons, resulting in low sample ionization efficiency and a small number of detectable samples, which further leads to low detection accuracy. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention provides a polycyclic time-of-flight mass spectrometer.

[0006] The specific technical solution of this invention is as follows:

[0007] 1. An ion source ring component, comprising at least one electron source assembly, the electron source assembly including a repulsion plate capable of repelling electrons, the surface of the repulsion plate being arc-shaped and a filament disposed on the concave side of the repulsion plate.

[0008] 2. According to the annular component of item 1, the number of the electronic source components is 1, 2, 3, 4, 5 or 6, preferably the number of the electronic source components is 3 or 4, and the adjacent electronic source components are connected end to end.

[0009] 3. According to the annular member described in item 1 or 2, the electron source assembly further includes two electrode side edges disposed opposite to each other on both sides of the repulsion electrode plate, the electrode side edges being perpendicular to the repulsion electrode plate and integrally formed with the repulsion electrode plate.

[0010] 4. According to the annular component described in item 3, the electronic source assembly further includes two pillars, which are respectively located on the side edge of the electrode plate and at both ends of the repulsive electrode plate, and the two ends of the filament are respectively connected to the two pillars.

[0011] 5. According to the annular component described in item 3, the filament is made of nickel-chromium alloy, and the repulsive electrode plate and the side edge of the electrode plate are both made of stainless steel.

[0012] 6. An ion funnel comprising an inner ring assembly and an outer ring assembly arranged coaxially, wherein a channel is formed between the inner ring assembly and the outer ring assembly, and the cross-sectional area of ​​the channel decreases from one end to the other.

[0013] 7. According to the ion funnel of item 6, the inner ring assembly includes an inner tube and at least one inner electrode plate. Multiple inner ring grooves are uniformly formed on the outer periphery of the inner tube. The inner electrode plates are respectively disposed in the inner ring grooves. The inner electrode plates are annular and the ring width of the inner electrode plates increases along the direction of decreasing channel cross-sectional area.

[0014] 8. According to the ion funnel described in item 7, the outer ring assembly includes an outer electrode plate corresponding to the inner electrode plate and an outer sleeve. The inner side of the outer sleeve is uniformly provided with a plurality of outer ring grooves. The outer electrode plate is disposed in the outer ring groove. Along the direction of decreasing channel cross-sectional area, the ring width of the outer electrode plate increases.

[0015] 9. The ion funnel according to item 8, wherein the inner tube and outer tube are made of PTFE plastic, and the inner electrode and outer electrode are both made of stainless steel.

[0016] 10. A polycyclic time-of-flight mass spectrometer, comprising a working chamber, a vacuum pump communicating with the interior of the working chamber on the working chamber, an injection tube at one end of the working chamber, and coaxially arranged inside the working chamber an ion source ring component as described in items 1-5, a first anode plate, a second anode plate, a guide electrode, an ion funnel as described in items 6-9, a deflection electrode, a reflector electrode, and a detector.

[0017] 11. The mass spectrometer according to item 10, wherein the first anode plate and the second anode plate are respectively located at the annular center of the ion source annular component, and the first anode plate and the second anode plate are respectively located on both sides of the annular center, the first anode plate and the second anode plate are both circular plates adapted to the ion source annular component, and the first anode plate is disposed on the side of the second anode plate near the sample inlet tube.

[0018] 12. The mass spectrometer according to item 11, wherein the annular ion source component is disposed at one end of the working chamber near the sample inlet tube, the sample inlet tube and the annular ion component are coaxially arranged, and one end of the sample inlet tube passes through the first anode plate and is located between the first anode plate and the second anode plate.

[0019] 13. The mass spectrometer according to item 10, wherein the ion funnel is disposed on the side of the ion source annular component away from the injection tube, a central column is disposed at the axial center of the ion funnel, the guide electrode is disposed between the ion funnel and the ion source annular component, and the guide electrode is disposed on the central column.

[0020] 14. The mass spectrometer according to item 10, wherein the ion funnel comprises an inner electrode and an outer electrode, the voltages of the outer electrode and the inner electrode being equal.

[0021] 15. In the mass spectrometer according to item 14, the voltage of the outer electrode and the inner electrode increases in a direction away from the sample inlet tube.

[0022] 16. The mass spectrometer according to item 10, wherein the reflector is disposed on the side of the ion funnel away from the injection tube and near the end of the working chamber opposite to the injection tube, and the detector is disposed on the side of the ion funnel near the reflector and close to the center.

[0023] 17. The mass spectrometer according to item 16, wherein the deflection electrode is disposed between the reflector and the ion funnel and near the outlet of the seed ion in the ion funnel, the deflection electrode comprising a voltage-adjustable first deflection plate and a second deflection plate, the first deflection plate being coaxially disposed outside the second deflection plate.

[0024] This invention discloses a ring-type time-of-flight mass spectrometer that uses a ring-shaped ion source to generate electrons. Repulsion plates repel the generated electrons, causing them to be repeatedly repelled between the ring-shaped repulsion plates. The electrons oscillate back and forth inside the ion source, reducing electron waste and increasing the electron density inside the ion source. Therefore, when the sample enters the ion source, more electrons react with it, thereby improving the ionization efficiency of the sample. At the same time, an ion funnel is used to collect the ions, reducing the possibility of ion scattering during flight. After deflection, the ions move to the detector, enabling the detector to detect more ions, thus improving the detection accuracy of the mass spectrometer. Attached Figure Description

[0025] Figure 1 This is an overall schematic diagram of the mass spectrometer used in this application;

[0026] Figure 2 This is a schematic diagram of the annular structure of the ion source of the mass spectrometer in this application.

[0027] In the figure, 1 is the sample inlet tube; 2 is the ion source; 2a is the repulsion plate; 2b is the side edge of the plate; 2c is the filament; 2d is the support; 3 is the first anode plate; 4 is the second anode plate; 5 is the guide electrode; 6 is the ion funnel; 7 is the first deflection plate; 8 is the second deflection plate; 9 is the reflector electrode; and 10 is the detector. Detailed Implementation

[0028] The present invention will now be described in detail. While specific embodiments of the invention have been shown, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0029] It should be noted that certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that different terms may be used to refer to the same component. This specification and claims do not distinguish components based on differences in terminology, but rather on differences in function. The terms "comprising" or "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising but not limited to." The following descriptions are preferred embodiments for carrying out the invention; however, these descriptions are for the purpose of understanding the general principles of the specification and are not intended to limit the scope of the invention. The scope of protection of this invention is determined by the appended claims.

[0030] This invention relates to an ion source ring structure, specifically, as... Figure 2 As shown, it includes at least one electronic source component, which includes a repulsion plate 2a capable of repelling electrons. The surface of the repulsion plate 2a is curved in an arc shape, and a filament 2c is provided on the concave side of the repulsion plate 2a.

[0031] The repulsive plate 2a is a metal plate with a negative charge. According to the principle that like charges repel each other, the repulsive plate 2a will repel electrons.

[0032] The arc-shaped bending is achieved by bending the repulsion plate 2a along a direction perpendicular to the plate-shaped surface of the repulsion plate 2a, so that the surface of the repulsion plate 2a is curved and the repulsion plate 2a is bent into an arc shape.

[0033] The filament 2c here is made of a material that can generate electrons. The filament 2c can be arranged in a spiral shape with its central axis parallel to the repulsion plate 2a, or it can be arranged in a straight parallel shape.

[0034] The number of electronic source components is 1, 2, 3, 4, 5 or 6, preferably 3 or 4, and the adjacent electronic source components are connected end to end.

[0035] One end of an electronic source component is connected to the beginning of an adjacent electronic source component, and all the electronic source components are combined to form a ring. The number of electronic source components is preferably 3 or 4, which facilitates the installation, removal, and replacement of the electronic source components.

[0036] The electronic source assembly also includes two electrode side edges 2b disposed opposite to each other on both sides of the repulsion electrode plate 2a. The electrode side edges 2b are perpendicular to the repulsion electrode plate 2a and are integrally formed with the repulsion electrode plate 2a.

[0037] The side edge 2b of the electrode plate extends perpendicularly to the concave side of the repulsive electrode plate 2a, making the side edge 2b of the electrode plate partially annular, and the inner ring of the side edge 2b of the electrode plate is concentric with the outer ring of the side edge 2b of the electrode plate. The side edge 2b of the electrode plate and the repulsive electrode plate 2a can be integrally formed by casting or by forging.

[0038] The electronic source assembly also includes two pillars 2d, which are located on the side edge 2b of the electrode plate and at both ends of the repulsive electrode plate 2a. The two ends of the filament 2c are connected to the two pillars 2d respectively.

[0039] Each electronic source assembly includes two electrode side edges 2b, and two support pillars 2d are disposed on the same electrode side edge 2b, located at both ends of the electrode side edge 2b. A storage through-hole adapted to the support pillar 2d is formed on the electrode side edge 2b, through which the support pillar 2d passes and is fixed. One end of the support pillar 2d is located at the center of the two electrode side edges 2b. Both ends of the filament 2c are fixed to the support pillar 2d. The support pillar 2d is made of an insulating material, such as ceramic, plastic, or glass, and is used to fix the filament 2c near the center between the two electrode side edges 2b.

[0040] The filament 2c is made of nickel-chromium alloy, and the repulsive electrode 2a and the electrode side edge 2b are both made of stainless steel.

[0041] The filament 2c is made of nickel-chromium alloy, which can improve oxidation resistance and service life. The repulsion plate 2a is made of stainless steel, which also improves oxidation resistance, reduces oxidation loss, and improves service life.

[0042] An ion funnel, reference Figure 1 It includes an inner ring group and an outer ring group arranged coaxially, and a channel is formed between the inner ring group and the outer ring group. The cross-sectional area of ​​the channel decreases from one end to the other.

[0043] The channel has a circular cross-sectional shape, and the size of the circular cross-section decreases from one end to the other. Ions will enter the channel from the end with the larger cross-sectional area and then exit from the other end with the smaller cross-sectional area, allowing the ions to accumulate inside the channel.

[0044] The inner ring assembly includes an inner tube and at least one inner electrode plate. Multiple inner ring grooves are uniformly formed on the outer periphery of the inner tube. The inner electrode plates are respectively disposed in the inner ring grooves. The inner electrode plates are annular and their ring width increases along the direction of decreasing channel cross-sectional area.

[0045] The inner ring groove extends circumferentially on the outer circumferential surface of the built-in tube, and the width of the inner ring groove is adapted to the thickness of the inner electrode plate.

[0046] The outer ring assembly includes an outer sleeve and outer electrodes that correspond one-to-one with the inner electrodes. Multiple outer ring grooves are evenly formed on the inner side of the outer sleeve, and the outer electrodes are disposed in the outer ring grooves. The ring width of the outer electrodes increases along the direction of decreasing channel cross-sectional area.

[0047] The outer electrode and the inner electrode are in one-to-one correspondence. The outer electrode is set on the outer periphery of the inner electrode, and the center of the end face of the outer electrode coincides with the center of the end face of the inner electrode.

[0048] The inner tube and outer tube are made of PTFE plastic, while the inner electrode and outer electrode are made of stainless steel.

[0049] The uniform insulation material of the inner tube and outer tube makes the inner and outer electrodes independent of each other, which facilitates the control of different inner and outer electrodes, and also facilitates replacement and disassembly.

[0050] A polycyclic time-of-flight mass spectrometer, referring to Figure 1 and Figure 2 The device includes a working chamber, on which a vacuum pump communicating with the interior of the working chamber is installed. An injection tube 1 is installed at one end of the working chamber. Inside the working chamber, a first anode plate 3, a second anode plate 4, a guide electrode 5, a deflection electrode, a reflector electrode 9, and a detector 10 are coaxially arranged.

[0051] The working chamber is a rectangular box made of metal, preferably stainless steel, to improve oxidation resistance and service life. The sample inlet tube 1 is a hollow glass tube, allowing the vaporized sample to enter the mass spectrometer for analysis. The sample inlet tube 1 and the working chamber are kept sealed.

[0052] The first anode plate 3 and the second anode plate 4 are respectively located at the annular center of the ion source annular component, and the first anode plate 3 and the second anode plate 4 are respectively located on both sides of the annular center. The first anode plate 3 and the second anode plate 4 are both circular plates adapted to the ion source annular component. The first anode plate 3 is disposed on the side of the second anode plate 4 close to the sample inlet tube 1.

[0053] The first anode plate 3 and the second anode plate 4 are flush with both ends of the ion source annular component, so that the first anode plate 3, the second anode plate 4 and the ion source annular component can be combined to form a closed cylinder. The distance between the first anode plate 3 and the second anode plate 4 is equal to the length of the ion source annular component in the axial direction of the cylinder. There are gaps between the ion source annular component and the first anode plate 3 and the second anode plate 4 to avoid charge exchange between the components.

[0054] The annular ion source component is located at one end of the working chamber near the sample inlet tube 1. The sample inlet tube 1 and the annular ion component are coaxially arranged. One end of the sample inlet tube 1 passes through the first anode plate 3 and is located between the first anode plate 3 and the second anode plate 4.

[0055] The sample can enter the space between the ring-shaped ion-forming components through the sample inlet tube 1. The electrons generated by the ring-shaped ion-forming components then ionize the sample. The first anode plate 3 and the second anode plate 4 provide energy to the ionized sample ions, enabling them to move at speed. Both the first anode plate 3 and the second anode plate 4 are mesh-like, allowing ions to pass through the pores and escape the electric field.

[0056] The ion funnel 6 is located on the side of the ion source annular component away from the injection tube 1. A central column is provided at the axial center of the ion funnel 6. The guide electrode 5 is located between the ion funnel 6 and the ion source annular component, and the guide electrode 5 is located on the central column.

[0057] The guide electrode 5 is an electrode plate with a charge that can guide ions. The guide electrode 5 has a mesh structure, and ions can pass through the mesh of the guide electrode 5. The size of the guide electrode 5 is larger than that of the first anode plate 3 and the second anode plate 4. After the ions are ejected from the ion source ring component, the ions will fly into the ion funnel 6 under the guidance of the guide electrode 5. The ion funnel 6 and the guide electrode 5 are both set on the central column. The central column fixes the distance between the guide electrode 5 and the ion funnel 6, and also makes it easier to keep the guide electrode 5 parallel to the ion funnel 6, thereby improving the efficiency of the guide electrode 5 in guiding ions into the ion funnel 6.

[0058] The voltages of the outer electrode and the inner electrode are equal.

[0059] The voltage between the inner and outer electrodes is equal, so there is no electric field along the radial direction of the ion funnel, thus reducing the possibility of ions colliding with the ion funnel.

[0060] The voltage of the outer electrode and the inner electrode increases in the direction away from the injection tube 1.

[0061] Due to the voltage difference between the inner and outer electrodes, the electric field in the ion funnel 6 is tangential to the edges of the inner and outer electrodes.

[0062] The reflector 9 is located on the side of the ion funnel 6 away from the sample inlet tube 1 and near the end of the working chamber opposite to the sample inlet tube 1. The detector 10 is located near the center of the ion funnel 6 on the side near the reflector 9.

[0063] Because ions have different masses, their velocities will differ after the same energy is applied. Based on the difference in their flight time, the detector 10 will also receive ions differently, thereby enabling the analysis of the sample composition.

[0064] The deflection electrode is disposed between the reflector 9 and the ion funnel 6 and near the outlet of the ion funnel 6. The deflection electrode includes a voltage-adjustable first deflection plate 7 and a second deflection plate 8. The first deflection plate 7 is coaxially disposed outside the second deflection plate 8.

[0065] The voltage difference between the first deflection plate 7 and the second deflection plate 8 determines the angle at which ions can be deflected when they enter the space between the first deflection plate 7 and the second deflection plate 8. The ultimate goal of controlling the voltage between the first deflection plate 7 and the second deflection plate 8 is to enable ions to accurately hit the detector 10. Therefore, when controlling the voltage between the first deflection plate 7 and the second deflection plate 8, it is necessary to adjust the voltage based on the detection results on the detector 10.

[0066] refer to Figure 1 and Figure 2 The present invention provides a polycyclic time-of-flight mass spectrometer, wherein the working chamber is a sealed space and a vacuum pump is connected to the working chamber. The vacuum pump extracts the air inside the working chamber to keep the working chamber in a vacuum state, thereby reducing the interference of air on ions and electrons and improving the accuracy of measurement results.

[0067] A sample inlet tube 1 is provided at one end of the working box. The sample inlet tube 1 is located at the center of the end face of the working box and is perpendicular to the end face of the working box. The sample inlet tube 1 passes through the working box and enters the interior of the working box.

[0068] Ion source 2, ion funnel 6, guide electrode 5, detector 10, deflector electrode 9, and reflector electrode 9 are all coaxially arranged inside the working chamber with the sample inlet tube 1. Ion source 2 is located at the end of the working chamber near the sample inlet tube 1, allowing the sample to enter the ion source 2 from the sample inlet tube 1 and be ionized by the ion source 2. Ion funnel 6 is located on the side of ion source 2 near the reflector electrode 9, and guide electrode 5 is located between ion funnel 6 and ion source 2. Guide electrode 5 guides the ions inside ion source 2, causing them to move towards ion funnel 6 and enter the ion source 2. Inside the funnel 6, the ion funnel 6 gathers ions and then ejects them; the ions ejected from the ion funnel 6 enter the reflector 9 and then move in the opposite direction, increasing the ion's travel distance in the same movement space and improving the detection accuracy of the ions; the detector 10 is set at the center of the ion funnel 6 near the reflector 9, and the deflector is set between the reflector 9 and the ion funnel 6, at the ion outlet of the ion funnel 6. After being deflected by the deflector and flipped by the reflector 9, the ions will gather towards the center, and by adjusting the deflector, the ions will move onto the detector 10.

[0069] The first anode plate 3 and the second anode plate 4 are disposed at the center of the ion source annular component, and the first anode plate 3 and the second anode plate 4 are respectively flush with the two sides of the ion source annular component. The first anode plate 3 is disposed on the side of the second anode plate 4 closer to the sample inlet tube 1.

[0070] One end of the injection tube 1 passes through the first anode plate 3 and enters between the first anode plate 3 and the second anode plate 4. The other end of the injection tube 1 is connected to the outside. The sample to be tested enters between the first anode plate 3 and the second anode plate 4 through the injection tube 1.

[0071] Two adjacent electron source components are connected end to end, and all electron source components together form a ring. The number of electron source components can be 1, 2, 3, 4, 5, 6, etc., and preferably, the number of ion source ring components is 3 or 4.

[0072] The repulsive plate 2a is curved in an arc shape along its surface. Both sides of the repulsive plate 2a extend in the vertical direction toward the concave side to form two opposing plate side edges 2b. The repulsive plate 2a and the plate side edges 2b are integrally formed. Two support pillars 2d are provided on one of the plate side edges 2b. The two support pillars 2d are located near the two ends of the plate side edge 2b, and the support pillars 2d penetrate the plate side edge 2b and are located between the two plate side edges 2b.

[0073] The filament 2c is disposed on the concave side of the repulsion plate 2a. The filament 2c is made of nickel-chromium alloy. The two ends of the filament 2c are respectively fixed to the ends of the two pillars 2d located between the two side edges 2b of the plates. The filament 2c is parallel to the repulsion plate 2a and is located at the center between the two side edges 2b of the plates.

[0074] Both the repulsive plate 2a and the side edge 2b are made of stainless steel and carry a negative charge, thus repelling the electrons generated by the filament 2c. The repulsive plates 2a and 2b enclose the filament 2c, causing the electrons generated by the filament 2c to be ejected towards the concave side of the repulsive plate 2a under the influence of the plates.

[0075] When the repulsive plates 2a combine to form a ring, the electrons generated by the filament 2c are repelled to the opposite retarded plate by the repulsive plates 2a and the side edges 2b of the plates. Then they are repelled again by the concave side of the repulsive plates 2a, which causes the electrons generated by the filament 2c to oscillate back and forth in the ring region. This greatly increases the probability of electrons colliding with the sample, improves the utilization of electrons, and also improves the ionization efficiency of the sample.

[0076] The first anode plate 3 and the second anode plate 4 are flush with the side edge 2b of the electrode plate, respectively. There is a voltage between the first anode plate 3 and the second anode plate 4, which can provide energy to electrons, enabling them to have sufficient kinetic energy to react with the sample. Furthermore, the first anode plate 3 and the second anode plate 4 can also absorb unreacted electrons, reducing electron leakage and contamination.

[0077] The guiding electrode 5 is an electrode plate that guides ions. Ions move towards the ion funnel 6 through the electrode plate. To ensure that ions can enter the ion funnel 6, the first anode plate 3, the second anode plate 4, and the guiding electrode 5 are all mesh structures. This allows the first anode plate 3, the second anode plate 4, and the guiding electrode 5 to all carry a potential and also provide channels for ions to pass through.

[0078] The inner tube and outer tube are made of PTFE plastic. The inner tube is coaxially arranged inside the outer tube. An outer ring assembly and an inner ring assembly are arranged between the inner tube and the outer tube. The inner ring assembly is arranged on the outer surface of the inner tube, and the outer ring assembly is arranged on the inner surface of the outer tube.

[0079] The central column is positioned at the center of the guide electrode 5, and the built-in tube is fitted onto the outer circumference of the central column, thus the guide electrode 5 and the built-in tube are coaxial. When the guide electrode 5 is controlled to be perpendicular to the central column, the guide electrode 5 and the ion funnel 6 are placed in a parallel position.

[0080] The outer ring group is coaxially arranged outside the inner ring group, and there is a gap between the outer ring group and the inner ring group, forming a channel for ions to pass through. The cross-sectional area of ​​the channel decreases along the direction away from the ion source 2.

[0081] The inner electrode is made of stainless steel and is ring-shaped. Multiple inner ring grooves are evenly opened on the outer circumference of the inner tube. The inner electrode is adapted to and corresponds to the outer ring groove. The inner electrode is snapped into the inner ring groove. Along the direction away from the ion source 2, the ring width of the inner electrode increases.

[0082] The outer electrode is made of stainless steel and is ring-shaped. Multiple outer ring grooves are evenly opened on the inner circumferential surface of the outer sleeve. The outer electrode is set inside the outer ring groove. The inner electrode and the outer electrode are set one-to-one. The outer electrode is coaxially set on the outside of the inner electrode. Along the direction away from the ion source 2, the ring width of the outer electrode increases.

[0083] The voltages of the corresponding inner and outer electrodes are equal. Along the direction away from the ion source 2, the voltages of the inner and outer electrodes increase. Therefore, the direction of the electric field in the channel is tangent to the edge of the channel. Thus, when ions enter the ion funnel 6, they will gather in the channel under the action of the electric field and be ejected at the end of the channel away from the ion source 2.

[0084] Because the ion channel cross-section is a ring with decreasing area, when ions are ejected from the ion funnel 6, the ions are circular and then enter the deflection electrode.

[0085] The first deflecting plate 7 and the second deflecting plate 8 are both bent into a circle along the surface. The first deflecting plate 7 is coaxially arranged on the outside of the second deflecting plate 8. The voltage between the first deflecting plate 7 and the second deflecting plate 8 can be adjusted, and a deflecting electric field is formed between the first deflecting plate 7 and the second deflecting plate 8.

[0086] After the ions are ejected from the ion funnel 6, they will be circular and move along the axis. Then they will enter the deflection electric field of the first deflection plate 7 and the second deflection plate 8. The deflection electric field will cause the ions to deflect radially and gather towards the center.

[0087] As the ions continue to move, they enter the reflector 9. The reflector 9 reverses the axial motion of the ions, causing them to move in the opposite direction. This increases the flight distance of the ions inside the working chamber. When there is a velocity difference between the ions, the longer flight distance increases the gap between the ions, further improving the accuracy of ion measurement. When the ions move in the reflector 9, their radial motion remains unchanged. Therefore, by controlling the voltage between the first deflection plate 7 and the second deflection plate 8, the trajectory of the ions inside the working chamber can be controlled.

[0088] After being reflected by the reflector 9 and deflected by the deflector, the circular ion beam will converge towards the center and eventually reach the detector 10, from which the detection result can be obtained.

[0089] In summary, when using the mass spectrometer of this invention for detection, the sample needs to be placed inside a sealed container, the injection tube connected to the inside of the container, and the injection tube and container kept sealed. The container is then heated to accelerate the vaporization of the sample inside. After vaporization, the sample diffuses from the injection tube into the ion source. Simultaneously, electrons generated by the filament will oscillate back and forth between the annular components of the ion source under the repulsion of the repulsion plates and the side edges 2b of the plates. The gaseous sample is bombarded by electrons, undergoing an ionization reaction, and becoming charged. The voltage difference between the first and second anode plates generates an electric field. The charged sample will be subjected to an electric field force in the electric field and move away from the injection tube. Then, the sample... Under the influence of the guiding electrode, the ions are injected between the inner and outer ring groups. As the ions move, the electric field between the inner and outer ring groups causes the ions to converge towards the center and exit at the end with the smaller cross-sectional area of ​​the channel. The ions ejected from the ion funnel will enter between the first and second deflection plates. The electric field formed between the first and second deflection plates will deflect the ions in the radial direction of the ion funnel. When the ions move to the reflecting electrode, their movement in the direction parallel to the central axis of the ion funnel will be reflected. By adjusting the voltage difference between the first and second deflection plates, the deflection angle of the ions can be controlled, thereby causing the ions to move to the detector, where the detector detects and analyzes the ions.

[0090] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A polycyclic time-of-flight mass spectrometer, characterized in that, The device includes a working chamber, on which a vacuum pump communicating with the inside of the working chamber is installed. An injection tube (1) is installed at one end of the working chamber. Inside the working chamber, an ion source ring component, a first anode plate (3), a second anode plate (4), a guide electrode (5), an ion funnel (6), a deflection electrode, a reflective electrode (9), and a detector (10) are coaxially arranged. The ion source annular component includes at least two electron source components. Each electron source component includes a repulsion plate (2a) capable of repelling electrons. The surface of the repulsion plate (2a) is curved in an arc shape, and a filament (2c) is provided on the concave side of the repulsion plate (2a). The electron source assembly also includes two electrode side edges (2b) disposed opposite to each other on both sides of the repulsion electrode plate (2a). The electrode side edges (2b) are perpendicular to the repulsion electrode plate (2a) and are integrally formed with the repulsion electrode plate (2a). Adjacent electron source assemblies are connected end to end. All electron source assemblies are combined into a ring shape. The repulsion electrode plate and the electrode side edges are formed by casting or forging. The ion funnel (6) includes an inner ring group and an outer ring group arranged coaxially, and a channel is formed between the inner ring group and the outer ring group. The cross-sectional area of ​​the channel decreases from one end to the other.

2. The mass spectrometer according to claim 1, characterized in that, The number of electronic source components is 2, 3, 4, 5 or 6.

3. The mass spectrometer according to claim 1, characterized in that, The number of electronic source components is 3 or 4.

4. The mass spectrometer according to claim 1, characterized in that, The electronic source assembly also includes two pillars (2d), which are located on the side edge (2b) of the electrode plate and at both ends of the repulsive electrode plate (2a). The two ends of the filament (2c) are connected to the two pillars (2d).

5. The mass spectrometer according to claim 1, characterized in that, The filament (2c) is made of nickel-chromium alloy, and the repulsion plate (2a) and the side edge of the plate (2b) are both made of stainless steel.

6. The mass spectrometer according to claim 1, characterized in that, The inner ring assembly includes an inner tube and at least one inner electrode plate. Multiple inner ring grooves are uniformly formed on the outer periphery of the inner tube. The inner electrode plates are respectively disposed in the inner ring grooves. The inner electrode plates are annular and their ring width increases along the direction of decreasing channel cross-sectional area.

7. The mass spectrometer according to claim 6, characterized in that, The outer ring assembly includes an outer electrode plate corresponding to the inner electrode plate and an outer sleeve. Multiple outer ring grooves are evenly formed on the inner side of the outer sleeve. The outer electrode plate is disposed in the outer ring groove. The ring width of the outer electrode plate increases along the direction of decreasing channel cross-sectional area.

8. The mass spectrometer according to claim 7, characterized in that, The inner tube and outer tube are made of PTFE plastic, while the inner electrode and outer electrode are made of stainless steel.

9. The mass spectrometer according to claim 1, characterized in that, The first anode plate (3) and the second anode plate (4) are respectively located at the annular center of the ion source annular component, and the first anode plate (3) and the second anode plate (4) are respectively located on both sides of the annular center. The first anode plate (3) and the second anode plate (4) are both circular plates adapted to the ion source annular component. The first anode plate (3) is located on the side of the second anode plate (4) close to the sample inlet tube (1).

10. The mass spectrometer according to claim 9, characterized in that, The annular ion source component is located at one end of the working chamber near the injection tube (1). The injection tube (1) and the annular ion component are coaxially arranged. One end of the injection tube (1) passes through the first anode plate (3) and is located between the first anode plate (3) and the second anode plate (4).

11. The mass spectrometer according to claim 1, characterized in that, The ion funnel (6) is located on the side of the ion source ring component away from the injection tube (1). A central column is provided at the axial center of the ion funnel (6). The guide electrode (5) is located between the ion funnel (6) and the ion source ring component, and the guide electrode (5) is located on the central column.

12. The mass spectrometer according to claim 1, characterized in that, The ion funnel (6) includes an inner electrode and an outer electrode, and the voltages of the outer electrode and the inner electrode are equal.

13. The mass spectrometer according to claim 12, characterized in that, The voltage of the outer electrode and the inner electrode increases in the direction away from the injection tube (1).

14. The mass spectrometer according to claim 1, characterized in that, The reflector (9) is located on the side of the ion funnel (6) away from the sample inlet tube (1) and close to the end of the working chamber opposite to the sample inlet tube (1). The detector (10) is located on the side of the ion funnel (6) close to the reflector (9) near the center.

15. The mass spectrometer according to claim 14, characterized in that, The deflection electrode is disposed between the reflector (9) and the ion funnel (6) and near the outlet of the ion funnel (6). The deflection electrode includes a voltage-adjustable first deflection plate (7) and a second deflection plate (8). The first deflection plate (7) is coaxially disposed on the outside of the second deflection plate (8).

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