Time-of-flight mass spectrometry reflector
By designing the reflective electric field area and ion emitter of the tapered cavity structure in the time-of-flight mass spectrometer, the problem of initial spatial dispersion of reflectors in the prior art is solved, and the resolution of the instrument is improved.
Patent Information
- Application Number
- CN202420902651.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-28
- Publication Date
- 2025-05-30
- Estimated Expiration
- 2034-04-28
AI Technical Summary
The reflectors of existing time-of-flight mass spectrometers have initial spatial dispersion problems, resulting in uneven flight distances of ions in the electric field, reducing the resolution of the instrument.
A time-of-flight mass spectrometer reflector is designed, including first and second reflected electric field regions in the housing, which are configured as tapered cavity, ion emitters and optional potential plate components, through which the ion beams fly uniformly in the reflected electric field to avoid initial energy dispersion.
Through this design, ions of different kinetic energy arrive at the detector at the same time, significantly improving the resolution of the instrument.
Smart Images
Figure CN222927418U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of mass spectrometers, and more specifically, to a time-of-flight mass spectrometry reflector. Background Art
[0002] The reflector is an energy correction device, which is installed at the end of the field-free flight area of the time-of-flight mass spectrometer and consists of a grid and a series of electrodes. Gradually increasing reflection voltages are applied to each electrode in turn. After ions enter the reflector, they are subjected to a force exerted by the reflection electric field, which is opposite to the direction of the velocity, resulting in a gradual decrease in the flight speed until it becomes zero; subsequently, the ions change the flight direction and enter the field-free flight area again. The structure of the reflector lengthens the flight distance of the ions, increases the total flight time of the ions, and more importantly, can compensate to a certain extent for the initial energy dispersion of ions with the same mass-to-charge ratio, enabling ions with different kinetic energies to reach the detector at the same time, thereby improving the resolution of the instrument.
[0003] Currently, the reflectors in the prior art have the problem of initial spatial dispersion. Thus, the flight distance of the ions in the time-of-flight mass spectrometer in the electric field will be affected by the initial spatial dispersion, resulting in a decrease in resolution. Summary of the Utility Model
[0004] The purpose of the utility model is to provide a time-of-flight mass spectrometry reflector to solve the technical problems existing in the related art.
[0005] The above technical purpose of the utility model is achieved through the following technical solutions: A time-of-flight mass spectrometry reflector, comprising:
[0006] A housing having a cavity inside, wherein a first reflection electric field region and a second reflection electric field region are provided in the cavity. The first reflection electric field region has opposite first and second ends, and the second end of the first reflection electric field region is connected to the second reflection electric field region. The first reflection electric field region is formed as a tapered cavity, and along the direction from the second end to the first end of the first reflection electric field region, the diameter of the first reflection electric field region gradually decreases;
[0007] An ion emission tube is provided in the cavity and extends along the up-and-down direction of the cavity. One end of the ion emission tube is used to receive an ion beam in the field-free flight area, and the other end of the ion emission tube faces the first reflection electric field region.
[0008] Optionally, the time-of-flight mass spectrometry reflector further includes a potential plate assembly;
[0009] The potential plate assembly is installed in the cavity. The potential plate assembly includes a plurality of potential plates. The plurality of potential plates are arranged at intervals in the up-and-down direction of the cavity. Through holes are formed in the plurality of potential plates, and the hole walls of the through holes on the plurality of potential plates jointly define the first reflected electric field region and the second reflected electric field;
[0010] Wherein, the diameter of the through hole near the first end of the first reflected electric field region is smaller than the diameter of the through hole near the second end of the first reflected electric field region, and the diameter of the through hole near the second end of the first reflected electric field region is equal to the diameter of the through hole far from the first reflected electric field region.
[0011] Optionally, the time-of-flight mass spectrometry reflector further includes at least two connecting members, and the potential plate assembly further includes at least two connecting screws and insulating pads;
[0012] At least two of the connecting members are arranged at intervals in the circumferential direction of the cavity. One ends of at least two of the connecting members are connected to the inner wall of the cavity, and the other ends of at least two of the connecting members are connected to the potential plate near the ion emission tube;
[0013] Both ends of at least two of the connecting screws are sequentially passed through the plurality of potential plates and are threadedly connected with connecting nuts;
[0014] Wherein, a plurality of the insulating pads are arranged between adjacent two of the potential plates, and the plurality of insulating pads are arranged at intervals in the circumferential direction of the potential plate and sleeved on the corresponding connecting screws.
[0015] Optionally, the housing includes a connected first housing and a second housing;
[0016] The first reflected electric field region and the second reflected electric field region are located in the second housing. A stop portion is formed on the inner cavity wall of the second housing, and a threaded hole is provided on the stop portion. The ion emission tube is threadedly connected with the threaded hole.
[0017] Optionally, the time-of-flight mass spectrometry reflector further includes a service pump, and a connection hole is formed on the second housing;
[0018] One end of the service pump is connected to the connection hole, and the other end of the service pump is used for communicating with a vacuum source.
[0019] Optionally, the potential plate is made of a flat metal plate.
[0020] In summary, the present utility model has the following beneficial effects: Through the provided ion emission tube, the ion beam emitted by the ion pulse generator can be sequentially emitted into the first reflection electric field region and the second reflection electric field region through the ion emission tube, and is sequentially reflected from the second reflection electric field region and the first reflection electric field region to the detector. Additionally, since the first reflection electric field region is configured as a tapered cavity, such a design can avoid ions with different kinetic energies arriving at the detector at the same time due to the dispersion of the initial energy (initial voltage), thereby improving the resolution of the instrument. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 is a three-dimensional schematic diagram of a time-of-flight mass spectrometry reflector in an embodiment of the present utility model;
[0022] Figure 2 is a sectional view of a time-of-flight mass spectrometry reflector in an embodiment of the present utility model.
[0023] In the figure:
[0024] 10. Housing;
[0025] 11. Cavity;
[0026] 12. First housing;
[0027] 13. Second housing;
[0028] 14. Stopping portion;
[0029] 15. Threaded hole;
[0030] 20. First reflection electric field region;
[0031] 30. Second reflection electric field region;
[0032] 40. Ion emission tube;
[0033] 50. Potential plate assembly;
[0034] 51. Potential plate;
[0035] 52. Through hole;
[0036] 53. Connecting screw;
[0037] 54. Insulating spacer;
[0038] 55. Connecting nut;
[0039] 60. Connector;
[0040] 70. Usage pump. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model. Therefore, the detailed description of the embodiments of the present utility model provided in the accompanying drawings is not intended to limit the scope of the claimed present utility model, but merely represents selected embodiments of the present utility model.
[0042] In the description of the present utility model, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features.
[0043] The following will further describe the present utility model in detail Figure 1-2 with reference to the accompanying drawings.
[0044] As Figures 1 to 2 shown, the present disclosure provides a time-of-flight mass spectrometer reflector, which includes a housing 10 and an ion emission tube 40. The interior of the housing 10 has a cavity 11. A first reflection electric field region 20 and a second reflection electric field region 30 are arranged in the cavity 11. The first reflection electric field region 20 has opposite first and second ends. The second end of the first reflection electric field region 20 is connected to the second reflection electric field region 30. The first reflection electric field region 20 is formed as a tapered cavity. Along the direction from the second end to the first end of the first reflection electric field region 20, the diameter of the first reflection electric field region 20 gradually decreases. The ion emission tube 40 is arranged in the cavity 11 and extends along the vertical direction of the cavity 11. One end of the ion emission tube 40 is used to receive an ion beam in a field-free flight region, and the other end of the ion emission tube 40 faces the first reflection electric field region 20.
[0045] It should be understood that the ion pulse generator periodically emits a part of the main ion beam in a pulsed form in the orthogonal direction to a high-potential drift region, which is the mass dispersion region of the time-of-flight mass spectrometer, so as to generate a new ion beam each time. The ion beam undergoes second-order focusing reflection in the reflector and is measured in the detector.
[0046] Through the above technical solution, by providing the ion emission tube 40, the ion beam emitted by the ion pulse generator can be sequentially emitted into the first reflection electric field region 20 and the second reflection electric field region 30 through the ion emission tube 40, and sequentially reflected from the second reflection electric field region 30 and the first reflection electric field region 20 to the detector. Additionally, since the first reflection electric field region 20 is configured as a tapered cavity, such a design can avoid ions with different kinetic energies reaching the detector at the same time due to the dispersion of the initial energy (initial voltage), thereby improving the resolution of the instrument.
[0047] To prevent the dispersion of the initial voltage, as an implementation, as Figures 1 to 2 shown, the time-of-flight mass spectrometer reflector further includes a potential plate assembly 50. The potential plate assembly 50 is installed in the cavity 11. The potential plate assembly 50 includes a plurality of potential plates 51. The plurality of potential plates 51 are spaced apart in the vertical direction of the cavity 11. Through holes 52 are formed on the plurality of potential plates 51. The hole walls of the through holes 52 on the plurality of potential plates 51 jointly define the first reflection electric field region 20 and the second reflection electric field. Among them, the diameter of the through hole 52 near the first end of the first reflection electric field region 20 is smaller than the diameter of the through hole 52 near the second end of the first reflection electric field region 20, and the diameter of the through hole 52 near the second end of the first reflection electric field region 20 is equal to the diameter of the through hole 52 far from the first reflection electric field region 20.
[0048] It should be noted that the smaller the distribution area of the ion beam, the greater the potential.
[0049] In view of this, since the diameter of the through hole 52 near the first end of the first reflection electric field region 20 is smaller than the diameter of the through hole 52 near the second end of the first reflection electric field region 20, the area of the ion beam in the through hole 52 near the first end of the first reflection electric field region 20 is the smallest, that is, the initial voltage is the largest. That is to say, this can prevent the dispersion of the initial voltage.
[0050] To be able to apply the continuously increasing potential to the potential plate 51 in the form of voltage, optionally, the potential plate 51 is made of a planar metal plate.
[0051] As an implementation, as Figures 1 to 2As shown, the time-of-flight mass spectrometry reflector may further include at least two connecting members 60. The potential plate assembly 50 further includes at least two connecting screws 53 and insulating pads 54. The at least two connecting members 60 are circumferentially spaced along the inner wall of the cavity 11. One end of the at least two connecting members 60 is connected to the inner wall of the cavity 11, and the other end of the at least two connecting members 60 is connected to the potential plate 51 near the ion emission tube 40. The two ends of the at least two connecting screws 53 are sequentially passed through a plurality of potential plates 51 and threadedly connected to connecting nuts 55. Among them, a plurality of insulating pads 54 are provided between adjacent potential plates 51. The plurality of insulating pads 54 are circumferentially spaced along the potential plate 51 and sleeved on the corresponding connecting screws 53.
[0052] By providing the connecting members 60, the potential plate assembly 50 can be installed in the housing 10. In addition, the potential plates 51 can be closely stacked (i.e., arranged in series one by one) together to maximally prevent the surrounding potential from penetrating into the interior. The individual plates are separated by insulating gaskets and supported together by the connecting screws 53. Among them, the insulating gaskets can play a role in precisely positioning the distance between adjacent potential plates 51.
[0053] In order to detachably install the ion emission tube 40 on the housing 10, as an implementation manner, as Figures 1 to 2 shown, the housing 10 includes a connected first housing 12 and a second housing 13. The first reflection electric field region 20 and the second reflection electric field region 30 are located in the second housing 13. A stop portion 14 is formed on the inner cavity wall of the second housing 13, and a threaded hole 15 is provided on the stop portion 14. The ion emission tube 40 is threadedly connected to the threaded hole 15.
[0054] As an implementation manner, as Figures 1 to 2 shown, the time-of-flight mass spectrometry reflector further includes a utility pump 70. A connection hole is formed on the second housing 13. One end of the utility pump 70 is connected to the connection hole, and the other end of the utility pump 70 is used to communicate with a vacuum source. In this way, by providing the utility pump 70, the mass spectrometer can be evacuated.
[0055] The above is only the preferred implementation manner of the present invention and is not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.
Claims
1. A time-of-flight mass spectrometer reflectron, characterized in that: include: A shell (10) having a cavity (11) therein, wherein a first reflection electric field region (20) and a second reflection electric field region (30) are arranged in the cavity (11), wherein the first reflection electric field region (20) has a first end and a second end opposite to each other, the second end of the first reflection electric field region (20) is connected to the second reflection electric field region (30), and the first reflection electric field region (20) is formed as a tapered cavity, wherein the diameter of the first reflection electric field region (20) gradually decreases along the direction from the second end of the first reflection electric field region (20) to the first end of the first reflection electric field region (20); An ion emitting tube (40) is arranged in the cavity (11) and extends in the up-down direction of the cavity (11); one end of the ion emitting tube (40) is used to receive the ion beam in the field-free flight zone, and the other end of the ion emitting tube (40) faces the first reflective electric field zone (20).
2. The time-of-flight mass spectrometer reflectron according to claim 1, characterized in that: The time-of-flight mass spectrometer reflectron also includes a potential plate assembly (50); The potential plate assembly (50) is installed in the cavity (11), the potential plate assembly (50) comprises a plurality of potential plates (51), the plurality of potential plates (51) are arranged at intervals along the up and down directions of the cavity (11), through holes (52) are formed on the plurality of potential plates (51), and the hole walls of the through holes (52) on the plurality of potential plates (51) jointly define the first reflection electric field region (20) and the second reflection electric field; The diameter of the through hole (52) near the first end of the first reflective electric field region (20) is smaller than the diameter of the through hole (52) near the second end of the first reflective electric field region (20), and the diameter of the through hole (52) near the second end of the first reflective electric field region (20) is equal to the diameter of the through hole (52) far from the first reflective electric field region (20).
3. The time-of-flight mass spectrometer reflectron according to claim 2, characterized in that: The time-of-flight mass spectrometer reflectron further comprises at least two connecting members (60), and the potential plate assembly (50) further comprises at least two connecting screws (53) and an insulating spacer (54); At least two of the connecting members (60) are arranged at intervals along the circumference of the cavity (11), one end of at least two of the connecting members (60) is connected to the inner wall of the cavity (11), and the other end of at least two of the connecting members (60) is connected to the potential plate (51) close to the ion emission tube (40); Both ends of at least two of the connecting screws (53) are respectively and sequentially inserted into the plurality of potential plates (51) and are threadedly connected to the connecting nuts (55); A plurality of insulating spacers (54) are provided between two adjacent potential plates (51), and the plurality of insulating spacers (54) are arranged at intervals along the circumference of the potential plates (51) and sleeved on the corresponding connecting screws (53).
4. The time-of-flight mass spectrometer reflectron according to claim 1, characterized in that: The housing (10) comprises a first housing (12) and a second housing (13) connected to each other; The first reflection electric field region (20) and the second reflection electric field region (30) are located in the second shell (13); a stopper (14) is formed on the inner cavity wall of the second shell (13); a threaded hole (15) is provided on the stopper (14); and the ion emission tube (40) is threadedly connected to the threaded hole (15).
5. The time-of-flight mass spectrometer reflectron according to claim 4, characterized in that: The time-of-flight mass spectrometer reflectron also includes a pump (70), and a connecting hole is formed on the second shell (13); One end of the use pump (70) is connected to the connection hole, and the other end of the use pump (70) is used to communicate with a vacuum source.
6. The time-of-flight mass spectrometer reflectron according to claim 2, characterized in that: The potential plate (51) is made of a flat metal plate.