An ion deflector for a mass spectrometer

Abstract

The present invention discloses an ion deflector for a mass spectrometer, which relates to the technical field of mass spectrometry analysis instruments, and comprises an inlet electrode, an outlet electrode and a repelling electrode distributed in a right triangle, wherein the inlet electrode and the outlet electrode serve as two right-angled sides of the right triangle, and the repelling electrode serves as the hypotenuse of the right triangle; a rotating electrode is arranged at the right angle in the right triangle, the repelling electrode is in a rectangular frame shape, and any two adjacent electrodes among the inlet electrode, the outlet electrode, the repelling electrode and the rotating electrode are insulated from each other; the voltage of the inlet electrode is positive, and the voltages of the outlet electrode, the repelling electrode and the rotating electrode are all negative; an ion inlet is arranged on the inlet electrode, and an ion outlet is arranged on the outlet electrode, and the rotating electrode can make the movement direction of the ions entering through the ion inlet deflect 90° toward the outlet electrode. The ion deflector for a mass spectrometer of the present invention improves the removal rate of photons and neutral particles and the ion transmission efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of mass spectrometry instruments, and in particular to an ion deflector for a mass spectrometer. Background Art

[0002] A mass spectrometer is an instrument that measures the mass-to-charge ratio of ions. Ions generated by an ion source pass through a deflection transmission device to reach a mass analyzer. After mass selection, the detector detects the signal to obtain information about the mass-to-charge ratio. The ion deflector has two functions: one is to transmit ions in a differential vacuum chamber, and the other is to block electrons, neutral particles, and photons to improve the final signal-to-noise ratio of the instrument. Ion deflectors can be divided into cylindrical baffle type, right-angle deflection type, and off-axis transmission type according to the way ion deflection is achieved.

[0003] For the cylindrical baffle type, a circular baffle is placed in the center of the cylindrical ion deflector. When ions fly into the deflector, they are affected by the electric field force and bypass the circular baffle to continue flying and enter the next structure. However, photons and neutral particles are not affected by the electric field force and fly in a straight line and hit the baffle to be removed. This method has a simple structural design, but the ion transmission efficiency is low.

[0004] For the right-angle deflection type, its working principle is that a fixed electric field is generated by a combination of electrodes of a specific structure. When ions pass through this electric field, they are deflected ninety degrees by the electric field force and continue to fly to the next structure, but photons and neutral particles are not affected by the electric field force, fly out of the deflector in a straight line and are removed.

[0005] For the off-axis transmission type, its working principle is to add a bias electric field to the transmission path of the ions, so that the transmission direction of the ions remains unchanged, but the transmission path is offset, so that they enter the next structure, while photons and neutral particles are not affected by the electric field force, and fly in a straight line and hit obstacles to be removed. This method has a simple structural design, but the removal efficiency of photons and neutral particles is low. Summary of the invention

[0006] The object of the present invention is to provide an ion deflector for a mass spectrometer to solve the problems existing in the above-mentioned prior art and to improve the removal rate of photons and neutral particles and the ion transmission efficiency.

[0007] To achieve the above-mentioned purpose, the present invention provides the following scheme: The present invention provides an ion deflector for a mass spectrometer, comprising an entrance electrode, an exit electrode and a repeller electrode distributed in a right triangle, wherein the entrance electrode and the exit electrode serve as two right-angled sides of the right triangle, and the repeller electrode serves as the hypotenuse of the right triangle; a rotating electrode is arranged at the right angle in the right triangle, the repeller electrode is in the shape of a rectangular frame, and any two adjacent electrodes among the entrance electrode, the exit electrode, the repeller electrode and the rotating electrode are insulated from each other; the voltage of the entrance electrode is positive, and the voltages of the exit electrode, the repeller electrode and the rotating electrode are all negative; an ion inlet is arranged on the entrance electrode, and an ion outlet is arranged on the exit electrode, and the rotating electrode can deflect the movement direction of ions entering through the ion inlet by 90° toward the exit electrode.

[0008] Preferably, there is a distance between any two adjacent electrodes among the inlet electrode, the outlet electrode, the repeller electrode and the rotating electrode.

[0009] Preferably, the thickness of the inlet electrode, the outlet electrode and the repeller electrode are all 2 mm.

[0010] Preferably, the rotating electrode is in a fan-shaped column, and the cross-section of the rotating electrode is a quarter circle, the curved side wall of the rotating electrode faces the repelling electrode, one side wall of the rotating electrode is parallel to the inlet electrode, and the other side wall of the rotating electrode is parallel to the outlet electrode.

[0011] Preferably, the voltage of the outlet electrode is lower than the voltage of the rotating electrode.

[0012] Preferably, in the mass spectrometer, the ions pass through the sampling cone and the skimmer cone in sequence along with the argon gas flow, enter the ion deflector through the ion inlet, finally leave the ion deflector through the ion outlet, and enter the mass analyzer in the mass spectrometer.

[0013] Compared with the prior art, the present invention has achieved the following technical effects:

[0014] The ion deflector used in the mass spectrometer of the present invention improves the removal rate of photons and neutral particles and the ion transmission efficiency. The ion deflector used in the mass spectrometer of the present invention improves the transmission efficiency of ions within a certain mass range (0-30 amu). The repelling electrode in the present invention is in the shape of a rectangular frame, that is, there is a rectangular notch in the middle, so that photons and neutral particles can pass directly through, thereby being discharged from the ion deflector, reducing pollution. Compared with the off-axis ion deflector, the removal rate of photons and neutral particles of the present invention is greatly improved, and the background noise is effectively reduced. The present invention has only 4 electrodes, which are easy to process, simple to combine, and low in manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0016] Figure 1 It is a schematic structural diagram of an ion deflector used in a mass spectrometer according to the present invention;

[0017] Figure 2 A diagram showing the position relationship of the ion deflector used in the mass spectrometer of the present invention;

[0018] Among them, 1. inlet electrode; 2. repeller electrode; 3. outlet electrode; 4. rotating electrode; 5. ion inlet; 6. ion outlet. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] The object of the present invention is to provide an ion deflector for a mass spectrometer to solve the problems existing in the above-mentioned prior art and to improve the removal rate of photons and neutral particles and the ion transmission efficiency.

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] like Figure 1 to Figure 2 As shown, this embodiment provides an ion deflector for a mass spectrometer, including an entrance electrode 1, an exit electrode 3 and a repeller electrode 2 distributed in a right triangle, the entrance electrode 1 and the exit electrode 3 serving as two right-angled sides of the right triangle, and the repeller electrode 2 serving as the hypotenuse of the right triangle; a rotating electrode 4 is provided at the right angle within the right triangle.

[0023] The repeller electrode 2 is in the shape of a rectangular frame, and any two adjacent electrodes among the entrance electrode 1, the exit electrode 3, the repeller electrode 2 and the rotating electrode 4 are insulated from each other; the voltage of the entrance electrode 1 is positive, and the voltages of the exit electrode 3, the repeller electrode 2 and the rotating electrode 4 are all negative; the entrance electrode 1 is provided with an ion inlet 5, and the exit electrode 3 is provided with an ion outlet 6.

[0024] The entrance electrode 1 is used to focus the ion beam coming from the skimmer cone. The rotating electrode 4 can deflect the movement direction of the ions entering through the ion entrance 5 by 90° toward the exit electrode 3; by applying a negative voltage to the exit electrode 3, the ion beam can be focused at the ion exit 6. The repeller electrode 2 cooperates with the rotating electrode 4 to form better electric field lines, which helps to deflect the ions.

[0025] There is a 2 mm gap between any two adjacent electrodes among the inlet electrode 1, the outlet electrode 3, the repeller electrode 2 and the rotating electrode 4. The thickness of the inlet electrode 1, the outlet electrode 3 and the repeller electrode 2 is 2 mm.

[0026] The rotating electrode 4 is in a fan-shaped column, and the cross section of the rotating electrode 4 is a quarter circle. The curved side wall of the rotating electrode 4 faces the repelling electrode 2. One side wall of the rotating electrode 4 is parallel to the inlet electrode 1, and the other side wall of the rotating electrode 4 is parallel to the outlet electrode 3.

[0027] The voltage of the outlet electrode 3 is lower than the voltage of the rotating electrode 4. It should be noted that the voltages on the inlet electrode 1, the outlet electrode 3, the repeller electrode 2 and the rotating electrode 4 can be adaptively adjusted according to the needs of ions of different masses.

[0028] The specific working principle of the ion deflector used in the mass spectrometer of this embodiment is as follows:

[0029] In the mass spectrometer, after the ions pass through the sampling cone and the skimmer cone in turn with the argon gas flow, they enter the ion deflector through the ion inlet 5. The entrance electrode 1 with a positive voltage focuses the ion beam coming from the skimmer cone; the rotating electrode 4 can make the movement direction of the ions entering through the ion inlet 5 deflect 90° toward the exit electrode 3, and the repeller electrode 2 cooperates with the rotating electrode 4 to form better electric field lines, which helps to deflect the ions; by applying a negative voltage to the exit electrode 3, the ion beam can be focused at the ion outlet 6, and the ions finally leave the ion deflector through the ion outlet 6 and enter the mass analyzer in the mass spectrometer.

[0030] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. An ion deflector for a mass spectrometer, characterized in that: The invention comprises an inlet electrode, an outlet electrode and a repeller electrode which are distributed in a right triangle, wherein the inlet electrode and the outlet electrode serve as two right-angled sides of the right triangle, and the repeller electrode serves as the hypotenuse of the right triangle; a rotating electrode is arranged at the right angle of the right triangle, and the repeller electrode is in a rectangular frame shape, and any two adjacent electrodes among the inlet electrode, the outlet electrode, the repeller electrode and the rotating electrode are insulated from each other; the voltage of the inlet electrode is positive, and the voltages of the outlet electrode, the repeller electrode and the rotating electrode are all negative; an ion inlet is arranged on the inlet electrode, and an ion outlet is arranged on the outlet electrode, and the rotating electrode can deflect the movement direction of ions entering through the ion inlet by 90° toward the outlet electrode.

2. The ion deflector for a mass spectrometer according to claim 1, characterized in that: There is a gap between any two adjacent electrodes among the inlet electrode, the outlet electrode, the repeller electrode and the rotating electrode.

3. The ion deflector for a mass spectrometer according to claim 1, characterized in that: The thickness of the inlet electrode, the outlet electrode and the repeller electrode are all 2 mm.

4. The ion deflector for a mass spectrometer according to claim 1, characterized in that: The rotating electrode is in a fan-shaped column, and the cross section of the rotating electrode is a quarter circle. The curved side wall of the rotating electrode faces the repelling electrode. One side wall of the rotating electrode is parallel to the inlet electrode, and the other side wall of the rotating electrode is parallel to the outlet electrode.

5. The ion deflector for a mass spectrometer according to claim 1, characterized in that: The voltage of the outlet electrode is lower than the voltage of the rotating electrode.

6. The ion deflector for a mass spectrometer according to claim 1, characterized in that: In the mass spectrometer, ions follow the argon gas flow through the sampling cone and the skimmer cone in sequence, enter the ion deflector through the ion inlet, and finally leave the ion deflector through the ion outlet and enter the mass analyzer in the mass spectrometer.

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