Multi-transformation time-of-flight mass spectrometry device and manufacturing method thereof

Abstract

The present invention relates to a multi-transformation time-of-flight mass spectrometer and a manufacturing method thereof. A multi-transformation time-of-flight mass spectrometer is provided, which can compensate for the distortion of the surrounding electric field with higher precision, thereby making the device miniaturized and improving the resolution. The multi-transformation time-of-flight mass spectrometer (1) comprises: a main electrode (21), which is an electrode that generates an electric field in a predetermined surrounding space, i.e., a surrounding electric field, which causes ions to fly in a circular manner for multiple times, and the main electrode (21) has openings (24, 25) for introducing ions into or out of the surrounding space; a compensation electrode mounting member (23) made of an insulator, which is fixed to the main electrode (21); and a compensation electrode (22), which is fixed to the compensation electrode mounting member (23) directly or by means of a substrate (221) and is arranged near the opening to compensate for the distortion of the surrounding electric field generated near the opening.

Description

Technical Field

[0001] The invention relates to a multi-transformation time-of-flight mass spectrometry device and a manufacturing method thereof. Background Art

[0002] In a time-of-flight mass spectrometer (TOFMS), the mass-to-charge ratio of an ion is usually calculated by measuring the time required to fly a predetermined distance, using the fact that when ions with different mass-to-charge ratios are accelerated with the same energy, the ions fly at a flight speed corresponding to the mass-to-charge ratio. Therefore, in a TOFMS, in order to improve the resolution, it is effective to increase the flight distance of the ions. However, in a linear TOFMS that causes ions to fly in a straight line, or a reflective TOFMS that causes ions to fly back and forth using a reflected electric field, if you want to increase the flight distance of the ions, you need to make the device larger in a specific direction (the flight direction of the ions).

[0003] Therefore, in recent years, a TOFMS called Multi Turn TOFMS (MT-TOFMS) has been developed (for example, Patent Document 1). In MT-TOFMS, an electric field is formed by causing ions to repeatedly orbit in a roughly circular, roughly elliptical, or figure "8"-shaped orbit and slightly move the orbit each time the orbit is rotated, thereby lengthening the flight distance of the ions without making the device larger in a specific direction. For example, the MT-TOFMS described in Patent Document 1 has a double-structured electrode, which includes an outer electrode in a roughly spheroidal shape formed by combining a plurality of segment electrodes and an inner electrode in a roughly spheroidal shape formed by being arranged on the inner side of the spheroid of the outer electrode and combining a plurality of segment electrodes that are respectively opposite to each segment electrode constituting the outer electrode. In this MT-TOFMS, an electric field (surrounding electric field) for causing ions to repeatedly orbit is formed in a spheroidal-shaped space (surrounding space) between the outer electrode and the inner electrode by applying a voltage to each segment electrode. Ions are introduced into the surrounding space from the ion introduction port provided at the outer electrode, and the surrounding electric field causes the ions to fly in the surrounding space along an orbit of a shape that slightly rotates around the axis of the substantially rotating ellipsoid every time it orbits. Then, after orbiting multiple times, the ions are discharged from the ion outlet provided at the outer electrode to the outside of the surrounding space and detected by an ion detector.

[0004] In MT-TOFMS, the orbit is formed in such a way that the position of the orbit moves slightly every time it orbits, so in the first few weeks, the ions will pass near the ion introduction port. The ion introduction port is an opening provided at the outer electrode. Near such an opening, the surrounding electric field may be distorted (it is called the distorted electric field) and cause the orbit of the ions to be disordered. The same is true near the ion export port. Therefore, in the MT-TOFMS described in Patent Document 1, an electrode (hereinafter referred to as the "main electrode" which is equivalent to the outer electrode and the inner electrode in Patent Document 1) for compensating the distortion of the surrounding electric field is independently arranged near the ion introduction port and the ion export port. The compensation electrode described in Patent Document 1 has a plurality of metal leads provided on a printed circuit board, and an electric field (compensation electric field) is additionally formed near the ion introduction port and the ion export port by applying a potential to each lead, thereby compensating for the distortion (distorted electric field) of the surrounding electric field formed by the main electrode.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. WO2013 / 057505 (Japanese Patent Publication No. 2014-531119) Summary of the invention

[0008] Problem that the invention aims to solve

[0009] As mentioned above, MT-TOFMS has the feature that the device does not need to be enlarged in a specific direction. Moreover, on the basis of miniaturizing the main electrode, if the density of the orbit is increased, that is, the movement of the position of the orbit generated by each orbit around the orbit is made smaller to increase the number of orbits, the resolution can be maintained and the overall miniaturization of the device can be achieved. In addition, if the size of the main electrode is maintained and the density of the orbit is increased to increase the number of orbits, the resolution can be improved. However, if the density of the orbit is increased, the chances of ions approaching the ion inlet and ion outlet during the orbital process will increase, and they will be easily affected by the distorted electric field caused by these inlets and outlets. Therefore, it is necessary to compensate for the distorted electric field using compensation electrodes with higher precision.

[0010] The problem to be solved by the present invention is to provide a multi-transformation time-of-flight mass spectrometer and a manufacturing method thereof, wherein the multi-transformation time-of-flight mass spectrometer can compensate for the distortion of the surrounding electric field with higher accuracy, thereby miniaturizing the device and improving the resolution.

[0011] Solutions for solving problems

[0012] The multi-transformation time-of-flight mass spectrometer of the present invention, which is completed in order to solve the above-mentioned problems, comprises:

[0013] A main electrode, which is an electrode for generating an electric field that causes ions to fly in a circular manner for multiple times in a predetermined surrounding space, namely, a surrounding electric field, and the main electrode has an opening for introducing ions into the surrounding space or leading them out from the surrounding space;

[0014] A compensating electrode mounting piece made of an insulator, which is fixed to the main electrode; and

[0015] The compensation electrode is fixed to the compensation electrode mounting member directly or via a substrate and is arranged near the opening to compensate for the distortion of the surrounding electric field generated near the opening.

[0016] Here, "near the opening" refers to the range from the opening to the following distance, which is a distance at which the influence of the electric field distortion caused by the opening on the orbit of the surrounding ions increases to a level that cannot be ignored. In addition, in the case where the main electrode is composed of an inner electrode and an outer electrode forming a surrounding space, "near the opening" is preferably within the range of the distance between the outer electrode and the inner electrode from the opening.

[0017] In the multi-transformation time-of-flight mass spectrometer of the present invention, preferably,

[0018] The compensation electrode mounting piece has two positioning pins,

[0019] The compensation electrode or the substrate has engaging holes arranged in one-to-one correspondence with the two positioning pins.

[0020] The multi-transformation time-of-flight mass spectrometer of the present invention can be appropriately manufactured using the following method. That is, the manufacturing method of the multi-transformation time-of-flight mass spectrometer of the present invention is a method for manufacturing a multi-transformation time-of-flight mass spectrometer, the multi-transformation time-of-flight mass spectrometer having: a main electrode, which is an electrode that generates an electric field, i.e., a surrounding electric field, in a predetermined surrounding space so that ions fly in a surrounding manner for multiple times, the main electrode having an opening for introducing ions into or out of the surrounding space; and a compensation electrode, which is arranged near the opening and compensates for the distortion of the surrounding electric field generated near the opening, wherein:

[0021] The manufacturing method of the multi-transformation time-of-flight mass spectrometer comprises the following steps:

[0022] A process of fixing the compensation electrode or the substrate on which the compensation electrode is mounted to the compensation electrode mounting member while the compensation electrode is held by the compensation electrode holding member and the compensation electrode mounting member is held by the compensation electrode holding member, using a fixture including a compensation electrode holding portion for holding the compensation electrode and a compensation electrode mounting member holding portion for holding the compensation electrode at a predetermined position relative to the compensation electrode; and

[0023] The step of fixing the compensation electrode mounting member near the opening of the main electrode.

[0024] Effects of the Invention

[0025] In the previous MT-TOFMS, the compensation electrode is set independently of the main electrode in a manner that does not contact the main electrode. In contrast, in the MT-TOFMS of the present invention, the compensation electrode is fixed to the main electrode by means of a compensation electrode mounting member formed by an insulator. As a result, the position of the compensation electrode relative to the main electrode can be set more accurately than before. Therefore, the compensation electric field generated by the compensation electrode can be used to compensate the distorted electric field generated near the opening of the main electrode with higher accuracy, which can make the device miniaturized and improve the resolution.

[0026] In the MT-TOFMS of the present invention, the position of the compensation electrode relative to the compensation electrode mounting member can be more accurately set and the distorted electric field can be compensated with higher precision when the following structure is present, that is, the compensation electrode mounting member has two positioning pins and the compensation electrode or the substrate has a structure in which snap-in holes are arranged one-to-one corresponding to the two positioning pins.

[0027] According to the manufacturing method of MT-TOFMS of the present invention, the compensation electrode or the substrate on which the compensation electrode is mounted is fixed to the compensation electrode mounting part while the compensation electrode is held in the compensation electrode holding part and the compensation electrode mounting part is held in the compensation electrode mounting part, thereby being able to more accurately set the position of the compensation electrode or the substrate relative to the compensation electrode mounting part, and being able to compensate for the distorted electric field with higher precision. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 (a) is a longitudinal sectional view showing one embodiment of the MT-TOFMS of the present invention, Figure 1 (b) is a top view.

[0029] Figure 2 It is a top view showing the trajectory of ions in the MT-TOFMS according to the present embodiment.

[0030] Figure 3(a) is a diagram obtained by simulation of the trajectory of ions flying near the ion introduction port in the structure in which the compensation electrode is removed from the MT-TOFMS of this embodiment. Figure 3 (b) is a diagram obtained by simulation of the trajectory of ions flying near the ion introduction port in the MT-TOFMS of the present embodiment in a state where the compensation electrode is operating.

[0031] Figure 4 It is a partially enlarged longitudinal sectional view of the MT-TOFMS according to the present embodiment.

[0032] Figure 5 (a) is a front view showing the compensation electrode mounting member of the MT-TOFMS according to the present embodiment, Figure 5 (b) is a top view.

[0033] Figure 6 (a) is a front view showing a protruding portion of a substrate of a compensation electrode of the MT-TOFMS of the present embodiment, Figure 6 (b) is a top view.

[0034] Figure 7 (a) is a front view showing a state in which the compensation electrode is mounted on the compensation electrode mounting member and the compensation electrode mounting member is mounted on the main electrode in the MT-TOFMS of this embodiment. Figure 7 (b) is a top view.

[0035] Figure 8 (a) is a front view showing a state where the compensation electrode is mounted on the compensation electrode mounting member in the MT-TOFMS of the modified example, Figure 8 (b) is a partial enlarged view. Figure 8 (c) is a local enlarged view of the substrate.

[0036] Fig. 9 (a) is a top view showing a fixture used when manufacturing MT-TOFMS of another modified example, Fig. 9 (b) is a side view.

[0037] Description of Reference Numerals

[0038] 1. TOFMS; 11. ion source; 12. ion detector; 20. ion flight unit; 21. main electrode; 211. outer electrode; 2111. mounting part; 2112. main electrode fixing bolt mounting hole; 212. inner electrode; 218. ion track; 219. surrounding space; 210. part of ions introduced from ion introduction port; 22, 32. compensation electrode; 221, 321. substrate; 2211. substrate protrusion; 2221, 2222, 3221, 3222, 3241, 3242, Locating pin engaging hole; 223, 323, compensation electrode fixing bolt mounting hole; 23, compensation electrode mounting piece; 231, main body of compensation electrode mounting piece; 232, 332, locating pin; 233, compensation electrode fixing bolt through hole; 234, main electrode fixing bolt through hole; 24, ion introduction port; 25, ion export port; 26, compensation electrode fixing bolt; 27, main electrode fixing bolt; 29, compensation electrode mounting surface; 324, conductor; 40, fixture; 41, main body of fixture; 42, locating pin provided on fixture; 43, recess. DETAILED DESCRIPTION

[0039] use Figures 1 to 9 Embodiments of the MT-TOFMS and a method for producing the same according to the present invention will be described.

[0040] (1) One embodiment of the MT-TOFMS of the present invention

[0041] Figure 1 (a) and (b) are schematic diagrams showing the MT-TOFMS 1 of this embodiment. The MT-TOFMS 1 of this embodiment includes an ion source 11 , an ion flight unit 20 , and an ion detector 12 .

[0042] The ion source 11 includes, for example, an ionizer for ionizing a sample and an ion trap for temporarily holding ions. A plurality of ions having various mass-to-charge ratios ionized by the ionizer are temporarily captured by the ion trap, and are simultaneously given predetermined energy at a predetermined timing and ejected as ion packets.

[0043] The ion flight portion 20 includes a main electrode 21 , a compensation electrode 22 , and a compensation electrode mounting member 23 .

[0044] The main electrode 21 includes an outer electrode 211 in the shape of a rotating ellipsoid and an inner electrode 212 in the shape of a substantially rotating ellipsoid provided inside the outer electrode 211. Figure 1(a) shows a cross-sectional view (longitudinal cross-sectional view) on a plane including the Z-axis, which is the rotation axis of the substantially rotating ellipsoid of the outer electrode 211 and the inner electrode 212, and the X-axis, which is an axis perpendicular to the Z-axis. When the main electrode 21 is cut along a plane including the Z-axis, the cross-sectional view is the same as that of the inner electrode 212 regardless of the azimuth angle (angle around the Z-axis). Figure 1 The shape shown in (a) is substantially the same shape. Figure 1 (b) shows a top view viewed from the positive direction of the Z axis. The axis perpendicular to the Z axis and the X axis is defined as the Y axis, and the plane including the X axis and the Y axis is defined as the XY plane.

[0045] The outer electrode 211 and the inner electrode 212 are formed by combining three groups of local electrode pairs S1, S2 and S3, which are formed by a pair of electrodes that are curved in the ZX plane and opposite to each other, and four groups of local electrode pairs L1, L2, L3 and L4, which are formed by a pair of electrodes that are linear in the ZX plane and opposite to each other. The local electrode pair S2 is arranged at both ends of the main electrode 21 in the X direction on the ZX plane and has a shape that is symmetrical about the X axis. The local electrode pair S1 is arranged at a position closer to the positive side of the Z direction than the local electrode pair S2. The local electrode pair S3 is arranged at a position closer to the negative side of the Z direction than the local electrode pair S2 in a manner that is symmetrical about the local electrode pair S1 about the X axis. The local electrode pair L2 is arranged between the local electrode pairs S1 and S2. The local electrode pair L3 is arranged between the local electrode pairs S2 and S3 and has a shape that is symmetrical about the local electrode pair L2 about the X axis. The local electrode pair L1 has an annular plate shape perpendicular to the Z axis and is arranged on the positive side in the Z direction and inside the local electrode pair S1 on the XY plane. The local electrode pair L4 is arranged on the negative side in the Z direction in a manner symmetrical to the local electrode pair L1 about the X axis.

[0046] The outer electrode 211 and the inner electrode 212 are formed into a substantially spheroidal shape as a whole by combining these local electrode pairs. The outer shape of the outer electrode 211 is, for example, 500 mm in the long axis direction (X direction, Y direction) and 300 mm in the short axis direction (Z direction). The interval between the outer electrode 211 and the inner electrode 212 is 20 mm. By reducing the overall size of the outer electrode 211 and the inner electrode 212, the overall size of the MT-TOFMS 1 can be reduced.

[0047] A potential is applied to the local electrode pairs S1, S2, and S3 that are curved in the ZX plane by a power source (not shown) to form an electric field from the outer electrode 211 toward the inner electrode 212. On the other hand, the same potential as that of the outer electrode 211 and the inner electrode 212 is applied to the local electrode pairs L1, L2, L3, and L4 that are linear in the ZX plane by a power source (not shown). As a result, a surrounding electric field that causes ions to surround in the space is formed in the space between the outer electrode 211 and the inner electrode 212. This space is referred to as a surrounding space 219.

[0048] The local electrode pair S1 in the outer electrode 211 is provided with an ion introduction port 24 for introducing ions ejected from the ion source 11 into the surrounding space 219. The ion introduction port 24 is provided at a position slightly deviated from the X-axis on the positive side of the Y direction, and is configured so that ions are incident from the ion source 11 approximately parallel to the X-axis. At the position where the ions have just been incident from the ion introduction port 24 into the surrounding space 219, they are subjected to a centripetal force from the surrounding electric field realized by the local electrode pair S1, and because the ion introduction port 24 is deviated from the X-axis on the positive side of the Y direction, they are subjected to a force in the direction of the X-axis. As a result, the ions will orbit in the surrounding space 219 along a substantially elliptical orbit and in the following orbit 218 (refer to Figure 2 ) flight, that is, each time it orbits, its orbit moves in the counterclockwise direction when viewed from the positive side of the Y direction. Figure 2 The trajectory 218 of the ions is shown in a top view on the XY plane.

[0049] The local electrode pair S3 is provided with an ion outlet 25 for extracting ions that have orbited multiple times (tens of times) in the orbiting space 219 from the orbiting space 219. The ions extracted from the ion outlet 25 fly on a linear track. The ion detector 12 is arranged on the linear track.

[0050] By utilizing the structures of the ion source 11, the main electrode 21, and the ion detector 12, a plurality of ions having various mass-to-charge ratios emitted from the ion source 11 are caused to fly in the surrounding space 219 in the main electrode 21, and the ion detector 12 detects the ions according to the time difference corresponding to the mass-to-charge ratio of each ion, thereby completing mass separation. However, at a position near the ion introduction port 24 through which the ions pass immediately after being introduced into the surrounding space 219, an opening is provided in the outer electrode 211 as the ion introduction port 24, so a distorted electric field is generated, and in this state, the trajectory of the ions deviates from the original position, and it may be impossible to extract the ions from the ion extraction port 25. Therefore, the MT-TOFMS 1 of this embodiment is provided with a compensation electrode 22.

[0051] like Figure 1 (a) and its partial enlarged view, namely Figure 4As shown, the compensation electrode 22 is a portion sandwiched by the local electrode pair S1 in the surrounding space 219. The compensation electrode 22 is located in the XY plane ( Figure 1 (b)) is arranged at a position closer to the ion introduction port 24 on the negative side in the Y direction than the position of the orbit of the ions introduced from the ion introduction port 24 after circling one circle and offset from the orbit in a manner not to overlap with the orbit. The distance between the ion introduction port 24 and the compensation electrode 22 is less than 10 mm, which is smaller than the interval between the outer electrode 211 and the inner electrode 212, i.e., 20 mm. The position of the compensation electrode 22 is within a range that would be affected by the distortion of the electric field caused by the ion introduction port 24 if there was no compensation electrode 22 (or if the compensation electrode 22 was not operating), and the position of the compensation electrode 22 is equivalent to the "near the opening (ion introduction port 24)". Figure 3 (a) shows a diagram obtained by simulation of the trajectory of ions flying near the ion introduction port 24 in the structure in which the compensation electrode 22 is removed from the MT-TOFMS 1 of this embodiment. As shown in the figure, it is known that when the compensation electrode 22 does not exist (does not operate), a part 210 of the ions introduced from the ion introduction port 24 will be scattered near the position after the ion trajectory 218 has circled once, and will be affected by the distortion of the electric field at the position where the compensation electrode 22 is configured.

[0052] The compensation electrode 22 is formed by arranging a plurality of linear conductors having a shape along the curve of the local electrode pair S1 on the ZX plane from the outer electrode 211 toward the inner electrode 212. The compensation electrode 22 is mounted on the surface of a substrate 221 formed of an insulator (alumina in the present embodiment). A substrate protrusion 2211, which is a part of the substrate 221, protrudes toward the outside of the main electrode 21 through a hole provided in the outer electrode 211. A power source not shown is connected to each linear conductor, thereby forming a compensation electric field from the outer electrode 211 toward the inner electrode 212. The compensation electric field is used to compensate for the distorted electric field formed in the main electrode 21 due to the presence of a hole in the outer electrode 211 that passes through the substrate 221 and serves as an opening for the ion introduction port 24. Figure 3 (b) shows a diagram obtained by simulating the trajectory of ions flying near the ion introduction port 24 when the compensation electrode 22 of the MT-TOFMS 1 of this embodiment is in operation. It is known that by operating the compensation electrode 22, ion scattering does not occur and the distorted electric field can be compensated.

[0053] However, if the compensation electrode 22 is not configured at the accurate position in the surrounding space 219, the compensation electric field will not be formed as designed, and the distorted electric field cannot be compensated. In particular, if the outer electrode 211 and the inner electrode 212 are reduced in size or the ion flight distance is lengthened without shortening the ion flight distance (i.e., without reducing the resolution), the interval of the orbit will become smaller, and thus it will be more susceptible to the distorted electric field near the ion introduction port 24. For example, if the outer diameter of the outer electrode 211 in the long axis direction is changed from 700 mm to 500 mm (the interval between the outer electrode 211 and the inner electrode 212 is set to 20 mm) without shortening the ion flight distance, the interval of the orbit will be changed from about 50 mm to less than 10 mm, and will pass through a position closer to the ion introduction port 24. Therefore, when the outer diameter of the outer electrode 211 in the long axis direction is 700 mm, the accuracy of the installation position of the compensation electrode 22 is sufficient as long as it is 500 μm or less. On the other hand, when the outer diameter is 500 mm, it needs to be set to 100 μm or less. Therefore, in the MT-TOFMS 1 of this embodiment, the compensation electrode mounting member 23 is used to configure the compensation electrode 22 at a more accurate position. In addition, the compensation electrode mounting member 23 is not limited to the case where the accuracy of the installation position of the compensation electrode 22 is set to 100 μm or less, and can also be used in the case where the accuracy of the installation position of the compensation electrode 22 is allowed to be lower than it (for example, 500 μm or less).

[0054] Hereinafter, the structure of the compensation electrode mounting member 23 will be described with reference to the direction in which the compensation electrode mounting member 23 is mounted on the main electrode 21. Figure 5 As shown, the compensation electrode mounting member 23 comprises: a main body 231, which is formed by an insulator that is roughly rectangular; two cylindrical positioning pins 232, which protrude from the main body 231 and are arranged on a surface on the negative side of the Y direction (this surface is referred to as the compensation electrode mounting surface 29); a compensation electrode fixing bolt through hole 233, which is provided with two in a manner of penetrating along the Y direction; and a main electrode fixing bolt through hole 234, which is provided with two in a manner of penetrating along the Z direction.

[0055] The plate surface of the substrate protrusion 2211 of the compensation electrode 22 is parallel to the ZX plane, and the substrate protrusion 2211 of the compensation electrode 22 is mounted on the negative side surface of the main body 231 of the compensation electrode mounting member 23 in the Y direction. Figure 6As shown, at the protruding portion 2211 of the substrate, two positioning pin engaging holes 2221, 2222 and a compensation electrode fixing bolt mounting hole 223 are provided corresponding to the positions of the two positioning pins 232 and the two compensation electrode fixing bolt through holes 233 of the compensation electrode mounting member 23. The positioning pin engaging hole 2221, which is one of the two positioning pin engaging holes and is provided on the side closer to the compensation electrode 22, has a circular planar shape that is substantially the same as the outer shape of the cylindrical positioning pin 232. The other positioning pin engaging hole 2222 has a long hole shape that has a width substantially the same as that of the positioning pin 232 in the Z direction and a width wider than that of the positioning pin 232 in the X direction.

[0056] like Figure 4 , Figure 7 As shown, a portion of the outer electrode 211 belonging to the local electrode pair S1 is provided with a mounting member fixing portion 2111 protruding outward, and the mounting member fixing portion 2111 is provided with two main electrode fixing bolt mounting holes 2112 corresponding to the two main electrode fixing bolt through holes 234 of the compensation electrode mounting member 23. Figure 7 In the top view of (b), since the substrate protrusion 2211 and the compensation electrode mounting member 23 are arranged on the inner side (lower side) of the mounting member fixing portion 2111, they do not appear in the top view, but are represented by solid lines for the sake of convenience of explanation.

[0057] like Figure 7 As shown in the figure, the substrate protrusion 2211 of the compensation electrode 22 is tightly engaged with the surface of the negative side of the compensation electrode mounting member 23 in the Y direction, and one positioning pin 232 is inserted into each of the two positioning pin engaging holes 2221 and 2222, and the compensation electrode fixing bolt 26 is respectively passed through the two compensation electrode fixing bolt through holes 233 and then installed in the compensation electrode fixing bolt installation hole 223, thereby fixing the substrate protrusion 2211 to the compensation electrode mounting member 23. In addition, the main electrode fixing bolt 27 is respectively passed through the two main electrode fixing bolt through holes 234 and then installed in the main electrode fixing bolt installation hole 2112, thereby fixing the compensation electrode mounting member 23 to the mounting member fixing portion 2111 provided on the outer electrode 211 of the main electrode 21. In this way, the compensation electrode 22 is fixed to the main electrode 21 via the compensation electrode mounting member 23.

[0058] The positions of the two positioning pins 232 and the diameter of the cylinder, the position and diameter of one positioning pin engaging hole 2221, and the position and the width in the Z direction of the other positioning pin engaging hole 2222 are made with a smaller tolerance (e.g., 10 μm to 30 μm) than the compensation electrode fixing bolt mounting hole 223 and the compensation electrode fixing bolt through hole 233. Therefore, the position of the compensation electrode 22 in the X direction can be set with high precision (e.g., less than 100 μm when the above tolerance is 10 μm to 30 μm) using one positioning pin engaging hole 2221 and the positioning pin 232 inserted in the one positioning pin engaging hole 2221. In addition, in the present embodiment, the other positioning pin engaging hole 2222 is set as a long hole having a width wider than the width of the positioning pin 232 in the X direction, thereby preventing the situation where it is difficult to insert the two positioning pins 232 into the positioning pin engaging holes 2221 and 2222 due to a slight error within the tolerance. In addition, the position of the compensation electrode 22 in the Z direction is set with high accuracy by using the two positioning pin engaging holes 2221 and 2222 and the positioning pins 232 inserted into the two positioning pin engaging holes 2221 and 2222. On the other hand, the position of the compensation electrode 22 in the Y direction is positioned with high accuracy by closely contacting the substrate protrusion 2211 of the compensation electrode 22 with the compensation electrode mounting surface 29.

[0059] As described above, in the MT-TOFMS 1 of the present embodiment, since the compensation electrode 22 is positioned with high precision, the distorted electric field generated near the ion introduction port 24 can be compensated with higher precision by using the compensation electric field. Thus, even if the movement of the orbit generated by the ions per orbit is reduced in order to miniaturize the main electrode 21 or to improve the resolution, so that the orbit after one orbit is close to the ion introduction port 24, the influence of the distorted electric field can be suppressed. Therefore, in the present embodiment, the MT-TOFMS can be miniaturized or the resolution can be improved.

[0060] (2) First Modification of MT-TOFMS of the Present Embodiment

[0061] Next, refer to Figure 8 A first modification of the MT-TOFMS of this embodiment will be described. The compensation electrode 32 of the MT-TOFMS of the first modification has a structure different from the compensation electrode 22 of the MT-TOFMS 1 of the above-mentioned embodiment. The structure other than the compensation electrode 32 (main electrode 21, compensation electrode mounting member 23, ion source 11, ion detector 12) is the same as that of the above-mentioned embodiment.

[0062] The compensation electrode 32 is formed by arranging a plurality of conductors 324 having a curved shape along the curve of the local electrode pair S1 on the ZX plane and having rigidity (capable of maintaining the shape) from the outer electrode 211 toward the inner electrode 212. Two positioning pin engaging holes 3421 and 3422 penetrating in the Y direction are provided in each conductor 324. One positioning pin engaging hole 3421 is circular, and the other positioning pin engaging hole 3242 is in the shape of a long hole extending along the curve of the conductor 324.

[0063] The compensation electrode 32 is mounted on a substrate 321 made of an insulator. The substrate 321 is provided with positioning pins 332 (different from the positioning pins 232 provided on the compensation electrode mounting member 23) extending to the negative side in the Y direction, the number of which is twice the number of the conductors 324. One positioning pin 332 is inserted into each of the positioning pin engaging holes 3241 and 3242, and on this basis, each conductor 324 is fixed to the substrate 321 by screws. The substrate 321 only supports a part of the compensation electrode 32, and the area thereof is smaller than that of the substrate 221 of the MT-TOFMS 1 of the above-mentioned embodiment. Thus, it is possible to suppress the accumulation of charge (charging) on ​​the substrate 321 made of an insulator in the surrounding space 219.

[0064] Similar to the substrate 221 of the above embodiment, the substrate 321 is further provided with two positioning pin engaging holes 3221, 3222 and a compensation electrode fixing bolt mounting hole 323 ( Figure 8 (c)). The positioning pins 232 provided on the compensation electrode mounting member 23 are inserted into the positioning pin engaging holes 3221 and 3222, respectively, and on this basis, the compensation electrode fixing bolts 26 respectively passing through the two compensation electrode fixing bolt through holes 233 are installed in the compensation electrode fixing bolt installation holes 323, thereby fixing the substrate 321 to the compensation electrode mounting member 23. In addition, similarly to the MT-TOFMS 1 of the above-mentioned embodiment, the compensation electrode mounting member 23 is fixed to the main electrode 21. Thus, the compensation electrode 32 fixed to the substrate 321 can be fixed at a predetermined position in the surrounding space 219 with high positional accuracy.

[0065] (3) Second Modification of MT-TOFMS of the Present Embodiment and Method for Manufacturing the Same

[0066] Next, refer to Fig. 9 A second variation of the MT-TOFMS of this embodiment and a method for manufacturing the same are described below. The MT-TOFMS of the second variation has a structure in which the positioning pin 232 and the positioning pin engaging holes 2221 and 2222 are omitted from the MT-TOFMS 1 of the above embodiment (not shown). In this variation, the MT-TOFMS is manufactured as follows. Fig. 9The jig 40 shown is used to position the compensation electrode 22 relative to the main electrode 21 , instead of using the positioning pins 232 and the positioning pin engaging holes 2221 , 2222 described above.

[0067] The jig 40 is provided with three positioning pins 42 and one recess 43 on one surface (this surface is set as the upper surface) of its plate-shaped main body 41. The recess 43 has a shape substantially the same as that of the compensation electrode mounting member 23 with the compensation electrode mounting surface 29 facing upward. The three positioning pins 42 are provided at positions where they contact the edge of the substrate 221 when the compensation electrode mounting member 23 is arranged in the recess 43 with the compensation electrode mounting surface 29 facing upward and when the substrate 221 of the compensation electrode 22 is arranged at an accurate position relative to the compensation electrode mounting member 23. Two of the three positioning pins 42 contact the curved edges formed on the substrate 221 along the curve of the compensation electrode 22, and the remaining one contacts the straight edge that intersects the curved edge.

[0068] In the MT-TOFMS of this modified example, during manufacturing, the compensation electrode mounting member 23 is arranged in the recess 43 with the compensation electrode mounting surface 29 facing upward, and then, the compensation electrode fixing bolts 26 respectively passing through two compensation electrode fixing bolt through holes 233 are installed in the compensation electrode fixing bolt mounting holes 223 while the substrate 221 is arranged so that the edge of the substrate 221 contacts the three positioning pins 42, thereby fixing the substrate 221 to the compensation electrode mounting member 23. Thereafter, the substrate 221 and the compensation electrode mounting member 23 are taken out of the jig 40, and then, the substrate protrusion 2211 of the substrate 221 is passed through the hole provided in the outer electrode 211, and the compensation electrode mounting member 23 is fixed to the mounting member fixing portion 2111 of the outer electrode 211. Thus, the compensation electrode 22 provided on the substrate 221 is accurately positioned.

[0069] (4) Other Modifications

[0070] The present invention is not limited to the embodiment and the two modified examples described above, and various modifications are possible.

[0071] For example, in the above-mentioned embodiment and two modified examples, the compensation electrode 22 is arranged near the ion introduction port 24, but the same compensation electrode may be arranged near the ion extraction port 25. In addition, the compensation electrode may be arranged only near the ion extraction port 25 without arranging the compensation electrode near the ion introduction port 24.

[0072] In the above-mentioned embodiment and two modified examples, the compensation electrode 22 is arranged at a position closer to the ion introduction port 24 than the position of the orbit of the ions introduced from the ion introduction port 24 after one circle, but it can also be arranged in a range of 20 mm or less from the ion introduction port 24 within the range of the distance between the outer electrode 211 and the inner electrode 212. In addition, as long as it is within the range that the influence of the distortion of the electric field caused by the ion introduction port 24 occurs, the compensation electrode 22 can be arranged at a position where the distance from the ion introduction port 24 is greater than the distance between the outer electrode 211 and the inner electrode 212. Such a range of influence that the distortion of the electric field occurs can be appropriately obtained by preliminary experiments or simulations. The same is true for the case where the compensation electrode is arranged near the ion export port 25.

[0073] In the first variant, the compensation electrode 32 and the substrate 321 are positioned by the positioning pins 332 provided on the substrate 321, and the substrate 321 and the compensation electrode mounting member 23 are positioned by the positioning pins 232 provided on the compensation electrode mounting member 23. However, the positioning pins 232 may be omitted and the substrate 321 and the compensation electrode mounting member 23 may be integrated. In this case, the substrate 321 and the compensation electrode mounting member 23 are considered as a whole integrated as the compensation electrode mounting member, and the compensation electrode 32 is directly mounted on the compensation electrode mounting member. Furthermore, the positioning pins 332 are used to realize the positioning of the compensation electrode 32 and the compensation electrode mounting member. The same is true for the case where the compensation electrode is arranged near the ion outlet 25.

[0074] [form]

[0075] It is easy for a person skilled in the art to understand that the above-described exemplary embodiments and their modifications are specific examples of the following aspects.

[0076] (Item 1)

[0077] The multi-transformation time-of-flight mass spectrometer of item 1 has:

[0078] A main electrode, which is an electrode for generating an electric field in a predetermined surrounding space so as to cause ions to fly in a circular manner for multiple times, namely, a surrounding electric field, and the main electrode has an opening for introducing ions into the surrounding space or leading them out from the surrounding space;

[0079] a compensating electrode mounting member made of an insulator, which is fixed to the main electrode; and

[0080] The compensation electrode is fixed to the compensation electrode mounting member directly or via a substrate and is arranged near the opening to compensate for the distortion of the surrounding electric field generated near the opening.

[0081] According to the multi-stage time-of-flight mass spectrometer of claim 1, the compensation electrode is fixed to the main electrode by means of a compensation electrode mounting member formed of an insulator, so that the position of the compensation electrode relative to the main electrode can be set more accurately than before. Therefore, the compensation electric field generated by the compensation electrode can be used to more accurately compensate for the distorted electric field generated near the opening of the main electrode, thereby making the device miniaturized and improving the resolution.

[0082] (Item 2)

[0083] The multi-transformation time-of-flight mass spectrometer of item 2 is based on the multi-transformation time-of-flight mass spectrometer of item 1, wherein:

[0084] The compensation electrode mounting piece has two positioning pins,

[0085] The compensation electrode or the substrate has engaging holes arranged in one-to-one correspondence with the two positioning pins.

[0086] According to the multi-stage time-of-flight mass spectrometer of item 2, the position of the compensation electrode relative to the compensation electrode mounting member can be set more accurately, thereby compensating for the distorted electric field with higher accuracy.

[0087] (Item 3)

[0088] The multi-stage time-of-flight mass spectrometer of item 3 is the multi-stage time-of-flight mass spectrometer according to item 2, wherein one of the engagement holes has a shape longer in one direction than the positioning pin of the two positioning pins that engages with the engagement hole.

[0089] According to the multi-transformation time-of-flight mass spectrometer of claim 3, it is possible to prevent the two positioning pins from being difficult to insert into the engagement holes due to a minute error within the tolerance.

[0090] (Item 4)

[0091] A multitransformation time-of-flight mass spectrometer according to item 4 is a multitransformation time-of-flight mass spectrometer according to any one of items 1 to 3, wherein the substrate supports only a portion of the compensation electrode.

[0092] According to the multi-stage time-of-flight mass spectrometer of item 4, it is possible to reduce the size of the substrate and suppress the accumulation of electric charges on the substrate (charging).

[0093] (Item 5)

[0094] The multi-transformation time-of-flight mass spectrometer of item 5 is a multi-transformation time-of-flight mass spectrometer according to any one of items 1 to 4, wherein:

[0095] The main electrode is composed of an outer electrode provided with the opening and an inner electrode provided inside the outer electrode at a predetermined distance from the outer electrode.

[0096] The surrounding space is the space between the outer electrode and the inner electrode,

[0097] The compensation electrode mounting member is disposed within the range of the predetermined distance from the opening.

[0098] According to the multi-stage time-of-flight mass spectrometer of item 5, the compensation electrode can be arranged in a range where the distortion of the electric field caused by the presence of the opening has a greater impact on the orbits of the surrounding ions, thereby effectively reducing the impact of the distortion of the electric field.

[0099] (Item 6)

[0100] The manufacturing method of a multi-transformation time-of-flight mass spectrometer of item 6 is a method for manufacturing a multi-transformation time-of-flight mass spectrometer, the multi-transformation time-of-flight mass spectrometer comprising: a main electrode, which is an electrode that generates an electric field, i.e., a surrounding electric field, in a predetermined surrounding space so that ions fly in a surrounding manner for multiple times, the main electrode having an opening for introducing ions into or out of the surrounding space; and a compensation electrode, which is arranged near the opening and compensates for the distortion of the surrounding electric field generated near the opening, wherein:

[0101] The manufacturing method of the multi-transformation time-of-flight mass spectrometer comprises the following steps:

[0102] A process of fixing the compensation electrode or the substrate on which the compensation electrode is mounted to the compensation electrode mounting member while the compensation electrode is held by the compensation electrode holding member and the compensation electrode mounting member is held by the compensation electrode holding member, using a fixture including a compensation electrode holding portion for holding the compensation electrode and a compensation electrode mounting member holding portion for holding the compensation electrode at a predetermined position relative to the compensation electrode; and

[0103] The step of fixing the compensation electrode mounting member near the opening of the main electrode.

[0104] According to the manufacturing method of the multi-type time-of-flight mass spectrometry device of item 6, the compensation electrode or the substrate on which the compensation electrode is mounted is fixed to the compensation electrode mounting part while the compensation electrode is held in the compensation electrode holding part and the compensation electrode mounting part is held in the compensation electrode mounting part. This allows the position of the compensation electrode or the substrate relative to the compensation electrode mounting part to be set more accurately, thereby allowing the distorted electric field to be compensated for with higher precision.

Claims

1. A multi-transformation time-of-flight mass spectrometry device, wherein: The multi-transformation time-of-flight mass spectrometer has: A main electrode, which is an electrode for generating an electric field, i.e., a surrounding electric field, in a predetermined surrounding space so that ions repeatedly orbit in a predetermined shape and rotate the orbit around a predetermined rotation axis each time the orbit is rotated, and the main electrode has an opening for introducing ions into the surrounding space or leading them out from the surrounding space; A compensating electrode mounting piece made of an insulator, which is fixed to the main electrode; as well as a compensation electrode, which is fixed to the compensation electrode mounting member directly or via a substrate and is arranged near the opening to compensate for the distortion of the surrounding electric field generated near the opening, The compensation electrode is arranged at a position in the surrounding space that does not overlap with the track.

2. The multi-transformation time-of-flight mass spectrometer according to claim 1, wherein: The compensation electrode mounting piece has two positioning pins, The compensation electrode or the substrate has engaging holes arranged in one-to-one correspondence with the two positioning pins.

3. The multi-transformation time-of-flight mass spectrometer according to claim 2, wherein: One of the engagement holes has a shape longer in one direction than the positioning pin engaged with the engagement hole among the two positioning pins.

4. The multi-transformation time-of-flight mass spectrometer according to claim 1, wherein: The substrate supports only a portion of the compensation electrode.

5. The multi-transformation time-of-flight mass spectrometer according to claim 1, wherein: The main electrode is composed of an outer electrode provided with the opening and an inner electrode provided inside the outer electrode at a predetermined distance from the outer electrode. The surrounding space is the space between the outer electrode and the inner electrode, The compensation electrode mounting member is disposed within the range of the predetermined distance from the opening.

6. A method for manufacturing a multi-transformation time-of-flight mass spectrometer, which is a method for manufacturing a multi-transformation time-of-flight mass spectrometer, the multi-transformation time-of-flight mass spectrometer comprising: a main electrode, which is an electrode for generating an electric field, i.e., a surrounding electric field, in a predetermined surrounding space in which ions repeatedly orbit in a predetermined shape and rotate the orbit around a predetermined rotation axis after each orbit, the main electrode having an opening for introducing ions into the surrounding space or leading them out from the surrounding space; and a compensation electrode, which is arranged near the opening and compensates for the distortion of the surrounding electric field generated near the opening, wherein: The manufacturing method of the multi-transformation time-of-flight mass spectrometer comprises the following steps: A process of fixing the compensation electrode or the substrate on which the compensation electrode is mounted to the compensation electrode mounting member while the compensation electrode is held by the compensation electrode holding member and the compensation electrode mounting member is held by the compensation electrode holding member, using a fixture including a compensation electrode holding portion for holding the compensation electrode and a compensation electrode mounting member holding portion for holding the compensation electrode at a predetermined position relative to the compensation electrode; and The step of fixing the compensation electrode mounting member near the opening of the main electrode, The compensation electrode is arranged at a position in the surrounding space that does not overlap with the track.

Images