JP2014123469A - Mass spectroscope and adjustment method of mass spectroscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique which allows for adjustment of the resonance characteristics without using a high breakdown voltage component, in the resonance characteristics adjustment section of an ion trap section.SOLUTION: In a mass spectroscope, an ion trap section 3 includes a rod electrode 202, an RF signal source 201, a resonance circuit 205, resonance characteristics adjustment sections 209a, 209b, a resonance characteristics measurement section 203, and a control section 204. The resonance characteristics adjustment sections 209a, 209b for adjusting the characteristics of the resonance circuit 205 are arranged between the RF signal source 201 and the rod electrode 202, and the voltage at both ends of the resonance characteristics adjustment sections 209a, 209b is set lower than a voltage applied to the rod electrode 202.

Description

  The present invention relates to a technology of a mass spectrometer, and in particular, is effective when applied to a mass spectrometer equipped with an ion trap part having a function of trapping ions and used for composition identification of a substance, and a method of adjusting the mass spectrometer. Technology.

  For example, in the mass spectrometer technology, the ion trap part of the mass spectrometer is composed of a plurality of electrodes having a hyperboloid cross-sectional shape, and a high-frequency high-frequency signal and a DC voltage are applied to each electrode. By doing so, it has a function of trapping ions by generating an electric field in a space formed by a plurality of electrodes.

  Examples of a technique related to a mass spectrometer provided with such an ion trap unit include techniques described in Patent Document 1 and Patent Document 2. Patent Document 1 includes a plurality of electrodes and variable capacitors connected to the respective electrodes, and adjusts the capacitance of each variable capacitor to adjust the drive frequency of the high-frequency signal source and the resonance frequency of the resonance circuit. Technology is disclosed. Patent Document 2 discloses a technique for providing a frequency driving mechanism for high-frequency current and sweeping the driving frequency so as to match the driving frequency and the resonance frequency.

  Moreover, there exists a technique described in patent document 3 as another technique regarding the mass spectrometer provided with the ion trap part. Patent Document 3 discloses a technology that includes a variable capacitor that is tuning means for adjusting the resonance frequency of a resonance circuit, and sets the variable capacitor so that the resonance frequency deviates from the frequency of the drive voltage.

Japanese Patent Laid-Open No. 2001-332211 Japanese Patent Laid-Open No. 2004-200082 Japanese Patent No. 3741097

  By the way, as a result of examination by the present inventor regarding the mass spectrometer equipped with the ion trap unit as described above, the following has been clarified.

  First, the principle of trapping ions in the ion trap unit will be described with reference to an example of the configuration of the ion trap unit in the mass spectrometer according to the prior art in FIG. Here, four electrode columns (hereinafter, referred to as rod electrodes 906a-1, 906a-2, 906b-1, and 906b-2) having a hyperboloid cross-sectional shape are arranged in parallel as the ion trap portion. An example of the rod electrode portion 902 is described. As an example of a circuit that generates a high-voltage high-frequency signal (hereinafter referred to as a high-voltage RF signal), an RF signal source 901 that outputs a high-frequency signal (hereinafter referred to as an RF signal), coils 907a and 907b, and a load A circuit including capacitors 908a, 908b, and 909 and a resonance circuit portion 905 formed by a parasitic capacitance of wiring and the like is shown.

  A high voltage RF signal having the same phase is applied to one pair of rod electrodes 906a-1 and 906a-2 facing each other with respect to the central axis of the four rod electrodes 906a-1, 906a-2, 906b-1, and 906b-2. When the differential high voltage RF signal is applied to the other rod electrode pair 906b-1 and 906b-2, the high voltage RF signal applied to the one rod electrode pair 906a-1 and 906a-2 is the center. The equation of motion of ions in the xy plane orthogonal to the axis is expressed by the following equation.

Here, e is the charge amount of the ion, V is the amplitude of the high voltage RF signal, m is the mass number of the ion, r ₀ is the radius of the circle inscribed in the space surrounded by the rod electrode, and ω is the high The angular frequency of the voltage RF signal, t represents time. This equation is known as the Matthew equation. Generally, in order to trap ions having a mass-to-charge ratio (m / e) in the ion trap portion, V and ω are determined so that q ≦ 0.908. It is known to be good.

  However, even if V and ω are determined as described above, the driving frequency of the RF signal source and the resonance frequency of the resonance circuit are different due to the inductance of the coil connected to each rod electrode pair, the manufacturing variation of the capacitor, the temperature fluctuation, and the like. By shifting, a desired high voltage RF signal amplitude may not be obtained, or a difference may occur in the amplitude of the high voltage RF signal applied to each pair of rod electrodes. In such a case, the equations of motion of (Equation 1) and (Equation 2) are not satisfied, so that the trapping efficiency of ions may be reduced, or ions having a desired mass-to-charge ratio may not be captured.

  As a technique for solving this problem, there are Patent Document 1 and Patent Document 2 described above. In Patent Document 1, the driving frequency and the resonance frequency can be adjusted by adjusting the capacitance of the variable capacitor connected to the rod electrode. In Patent Document 2, the drive frequency and the resonance frequency can be matched by sweeping the drive frequency.

  By the way, generally, a high voltage RF signal of several hundred V to several kV is applied to the rod electrode. For this reason, the method of Patent Document 1 described above requires a variable capacitor with a high withstand voltage, and there is a problem that the device is expensive. In addition, a high-voltage variable capacitor is generally a mechanical type that adjusts the capacity by mechanically moving the area of the opposing electrode. When automatic control is performed, mechanical parts such as actuators are required. This increases the cost and size of the equipment.

  On the other hand, the method described in Patent Document 2 described above makes the drive frequency and the resonance frequency coincide with each other without using a high withstand voltage variable capacitor. However, since the mass-to-charge ratio of ions to be captured changes by changing the drive frequency, the mass-to-charge ratio of the trapped ions is made constant by adjusting the amplitude of the applied high voltage RF signal each time the drive frequency is changed. In addition, there is a problem that calculation processing for correcting deviation of the mass axis is necessary, and adjustment control and calculation processing become complicated.

  The technique disclosed in Patent Document 3 described above is a technique for reducing the phase shift between the output waveform and the high-frequency high voltage, and is not a technique for adjusting the resonance characteristics. It doesn't take into account issues about

  Therefore, the present invention has been made in view of the above-described problems, and a typical object thereof is to adjust the resonance characteristics without using high-voltage components in the resonance characteristic adjustment section of the ion trap section. It is to provide the technology that makes it possible.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  (1) A typical mass spectrometer is a mass spectrometer provided with an ion trap part that separates a sample according to the mass of ions, and has the following characteristics.

  (1-1) The ion trap unit includes a rod electrode unit including four rod electrodes arranged in parallel to each other, an RF signal source that generates an RF signal, and an RF signal generated by the RF signal source. A high voltage RF signal is generated by resonance amplification, the high voltage RF signal is applied to one pair of rod electrodes facing each other with respect to the central axis of the four rod electrodes of the rod electrode portion, and the other pair The high voltage RF signal applied to one of the pair of rod electrodes is different from the resonance circuit part for applying a high voltage RF signal, and the resonance characteristic adjustment for adjusting the characteristic of the resonance circuit part Measure the resonance frequency and amplification factor of the resonance circuit section between the high voltage RF signal applied to one pair of rod electrode pairs and the differential high voltage RF signal applied to the other pair of rod electrode pairs Measured by the resonance characteristic measurement unit and the resonance characteristic measurement unit. Based on the information of the resonance frequency and the amplification factor of the resonant circuit and a control unit for adjusting the resonance characteristic adjustment unit. The resonance characteristic adjusting unit is arranged between the RF signal source and the rod electrode unit, and the voltage at both ends of the resonance characteristic adjusting unit is configured to be smaller than the voltage applied to the rod electrode unit. Features.

  (1-2) The ion trap unit includes a rod electrode unit including four rod electrodes arranged in parallel to each other, an RF signal source that generates an RF signal, and an RF signal generated by the RF signal source. A high voltage RF signal is generated by resonance amplification, the high voltage RF signal is applied to one pair of rod electrodes facing each other with respect to the central axis of the four rod electrodes of the rod electrode portion, and the other pair The high voltage RF signal applied to one of the pair of rod electrodes is different from the resonance circuit part for applying a high voltage RF signal, and the resonance characteristic adjustment for adjusting the characteristic of the resonance circuit part , An auxiliary AC signal source that applies a differential auxiliary AC signal different from the frequency of the high voltage RF signal to one set of rod electrode pairs, and a high voltage RF that is applied to one set of rod electrode pairs Differential applied to signal and other pair of rod electrodes A resonance characteristic measurement unit that measures the resonance frequency and amplification factor of the resonance circuit unit with the high-voltage RF signal, and a resonance characteristic adjustment unit that is based on the resonance frequency and amplification factor information of the resonance circuit unit measured by the resonance characteristic measurement unit. A control unit for adjustment. The first transformer is disposed between the auxiliary AC signal source and the RF signal source and one set of rod electrode pairs, the auxiliary AC signal and the RF signal are superimposed by the first transformer, and the resonance characteristics are adjusted. The portion is disposed between the auxiliary AC signal source and the first transformer, and the voltage at both ends of the resonance characteristic adjusting portion is configured to be smaller than the voltage applied to the rod electrode portion.

  (2) A typical method for adjusting a mass spectrometer is characterized by the following resonance frequency and amplification factor adjustment procedure in the configuration of the ion trap section of (1-1). In the control unit, while changing the drive frequency of the RF signal source, the high voltage RF signal applied to one set of rod electrodes and the other set of rod electrodes at each drive frequency is branched to the resonance characteristic measurement unit. input. In the resonance characteristic measurement unit, the amplitude of each input signal is reduced, each signal is converted into a DC signal, the converted DC signal is added, and the RF signal source when the added signal becomes the largest The drive frequency is detected as a resonance frequency and input to the control unit. The control unit determines whether or not the input resonance frequency is within a predetermined value range. If the resonance frequency is out of the predetermined value range as a result of the determination of the resonance frequency, the resonance characteristic adjustment unit is adjusted. Then, the resonance frequency is measured again, and if the resonance frequency is within a predetermined value range, the drive frequency is set. Subsequently, the resonance characteristic measuring unit measures the amplitude of the high voltage RF signal applied to one set of rod electrodes and the other set of rod electrode pairs and inputs them to the control unit. When the control unit obtains an amplification factor from the input amplitude, determines whether or not the amplification factor is within a predetermined value range, and as a result of the determination of the amplification factor, the amplification factor deviates from the predetermined value range Is characterized in that the resonance characteristic adjustment unit is adjusted, the amplitude is measured again to obtain the amplification factor, and the adjustment is terminated when the amplification factor is within a predetermined value range.

  Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

  In other words, a typical effect is that the resonance characteristics can be adjusted without using a high-voltage component in the resonance characteristics adjustment section of the ion trap section. As a result, the mass spectrometer can be reduced in cost, size, and measurement throughput can be improved.

It is a block diagram for demonstrating an example of a structure of the mass spectrometer which concerns on Embodiment 1 of this invention. FIG. 2 is a diagram for explaining an example of a configuration of an ion trap unit in the mass spectrometer of FIG. 1. FIG. 3 is a diagram for explaining an example of a configuration of a resonance characteristic measurement unit and a control unit in the ion trap unit of FIG. 2. 3 is a flowchart for explaining an example of a procedure for adjusting a resonance frequency and an amplification factor of a resonance characteristic adjusting unit in the ion trap unit of FIG. 2. It is a figure for demonstrating an example of a structure of the ion trap part in the mass spectrometer which concerns on Embodiment 2 of this invention. It is a figure for demonstrating an example of a structure of the ion trap part in the mass spectrometer which concerns on Embodiment 3 of this invention. It is a figure for demonstrating an example of a structure of the ion trap part in the mass spectrometer which concerns on Embodiment 4 of this invention. It is a figure for demonstrating an example of a structure of the ion trap part in the mass spectrometer which concerns on Embodiment 5 of this invention. It is a figure for demonstrating an example of a structure of the ion trap part in the mass spectrometer which concerns on a prior art.

  In the following embodiments, when it is necessary for the sake of convenience, the description will be divided into a plurality of embodiments or sections. However, unless otherwise specified, they are not irrelevant and one is the other. There are some or all of the modifications, details, supplementary explanations, and the like. Further, in the following embodiments, when referring to the number of elements (including the number, numerical value, quantity, range, etc.), especially when clearly indicated and when clearly limited to a specific number in principle, etc. Except, it is not limited to the specific number, and may be more or less than the specific number.

  Further, in the following embodiments, the constituent elements (including element steps and the like) are not necessarily indispensable unless otherwise specified and apparently essential in principle. Needless to say. Similarly, in the following embodiments, when referring to the shapes, positional relationships, etc. of the components, etc., the shapes are substantially the same unless otherwise specified, or otherwise apparent in principle. And the like are included. The same applies to the above numerical values and ranges.

[Outline of Embodiment of the Present Invention]
A mass spectrometer according to an embodiment of the present invention and a method for adjusting the mass spectrometer have the following features (for example, reference numerals of corresponding components in () and step S of the processing procedure. Etc.)

  (1) The mass spectrometer according to the present embodiment is a mass spectrometer having an ion trap section (3) for separating a sample according to the mass of ions, and has the following characteristics.

  (1-1) The ion trap unit includes a rod electrode unit (202, 502, 602, 702) including four rod electrodes arranged in parallel to each other, and an RF signal source (201, 501, 601, 701) and the RF signal generated by the RF signal source are resonantly amplified to generate a high-voltage RF signal, and one of the ones facing the central axes of the four rod electrodes of the rod electrode portion A high voltage RF signal is applied to a pair of rod electrode pairs, and a high voltage RF signal that is different from the high voltage RF signal applied to one pair of rod electrode pairs is applied to the other pair of rod electrode pairs. The resonance circuit unit (205, 505, 605, 705), the resonance characteristic adjustment unit (209, 509, 609, 709) for adjusting the characteristic of the resonance circuit unit, and one set of rod electrode pairs are applied. High voltage RF signal and the other Resonance characteristic measurement unit (203, 503, 603, 703) for measuring the resonance frequency and amplification factor of the resonance circuit unit with the differential high voltage RF signal applied to the pair of rod electrodes, and measurement by the resonance characteristic measurement unit And a control unit (204, 504, 604, 704) for adjusting the resonance characteristic adjustment unit based on the information on the resonance frequency and amplification factor of the resonance circuit unit. The resonance characteristic adjusting unit is arranged between the RF signal source and the rod electrode unit, and the voltage at both ends of the resonance characteristic adjusting unit is configured to be smaller than the voltage applied to the rod electrode unit. Features.

  (1-2) The ion trap unit includes a rod electrode unit (802) including four rod electrodes arranged in parallel to each other, an RF signal source (801) that generates an RF signal, and an RF signal source. The generated RF signal is resonantly amplified to generate a high voltage RF signal, and the high voltage RF signal is applied to one pair of rod electrodes opposed to the central axis of the four rod electrodes of the rod electrode portion. A resonance circuit unit (805) for applying a high voltage RF signal that is different from the high voltage RF signal applied to the one pair of rod electrodes to the other pair of rod electrodes; A resonance characteristic adjustment unit (809) for adjusting characteristics, and an auxiliary AC signal source (819) for applying a differential auxiliary AC signal different from the frequency of the high-voltage RF signal to one of the pair of rod electrodes. High power applied to one set of rod electrode pairs Resonance characteristic measurement unit (803) for measuring the resonance frequency and amplification factor of the resonance circuit unit of the RF signal and the differential high voltage RF signal applied to the other pair of rod electrode pairs, and measurement by the resonance characteristic measurement unit And a control unit (804) for adjusting the resonance characteristic adjustment unit based on the information on the resonance frequency and the amplification factor of the resonance circuit unit. A first transformer (815) is disposed between the auxiliary AC signal source and the RF signal source and one set of rod electrode pairs, the auxiliary AC signal and the RF signal are superimposed by the first transformer, and The resonance characteristic adjustment unit is disposed between the auxiliary AC signal source and the first transformer, and is configured such that the voltage at both ends of the resonance characteristic adjustment unit is smaller than the voltage applied to the rod electrode unit. And

  (2) The method for adjusting a mass spectrometer according to the present embodiment is characterized by the following resonance frequency and amplification factor adjustment procedure in the configuration of the ion trap section of (1-1). In the control unit, while changing the drive frequency of the RF signal source, the high voltage RF signal applied to one set of rod electrodes and the other set of rod electrodes at each drive frequency is branched to the resonance characteristic measurement unit. input. In the resonance characteristic measurement unit, the amplitude of each input signal is reduced, each signal is converted into a DC signal, the converted DC signal is added, and the RF signal source when the added signal becomes the largest The drive frequency is detected as a resonance frequency and input to the control unit (S1). In the control unit, it is determined whether or not the input resonance frequency is within a predetermined value range (S2). If the resonance frequency is out of the predetermined value range as a result of the determination of the resonance frequency, the resonance characteristic adjustment unit (S3), the resonance frequency is measured again, and if the resonance frequency is within a predetermined value range, the drive frequency is set (S4). Subsequently, the resonance characteristic measuring unit measures the amplitude of the high voltage RF signal applied to one set of rod electrodes and the other set of rod electrode pairs, and inputs them to the control unit (S5). In the control unit, an amplification factor is obtained from the input amplitude, and it is determined whether or not the amplification factor is within a predetermined value range (S6). As a result of the determination of the amplification factor, the amplification factor deviates from the predetermined value range. If so, the resonance characteristic adjustment unit is adjusted (S7), the amplitude is measured again to obtain the amplification factor, and the adjustment is terminated when the amplification factor is within a predetermined value range. To do.

  Each embodiment based on the outline of the embodiment of the present invention described above will be described in detail below based on the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the corresponding members have the corresponding reference characters without redundant description.

[Embodiment 1]
A mass spectrometer according to the present embodiment will be described with reference to FIGS.

<Mass spectrometer>
A mass spectrometer according to the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram for explaining an example of the configuration of the mass spectrometer.

  The mass spectrometer according to the present embodiment includes a sample introduction chamber 1, an ionization chamber 2, an ion trap unit 3, a detector 4, a data processing unit 5, a data output unit 6, and the like.

  The sample introduction chamber 1 is a mechanism for introducing a sample. The ionization chamber 2 is a mechanism that is mechanically connected to the sample introduction chamber 1 and ionizes the sample introduced into the sample introduction chamber 1. The ion trap unit 3 is a mechanical unit that is mechanically connected to the ionization chamber 2 and separates the sample ionized in the ionization chamber 2 according to the mass of ions.

  The detector 4 is a detector that is arranged in the ion trap unit 3 and detects ions having a predetermined mass among the ions separated by the ion trap unit 3. The data processing unit 5 is a functional unit that is electrically connected to the detector 4 and processes data obtained by detecting ions with the detector 4.

  The data output unit 6 is a functional unit that is electrically connected to the data processing unit 5 and outputs data obtained by processing by the data processing unit 5. The data output unit 6 includes a screen 7 for displaying data.

  In the mass spectrometer configured as described above, the operation of the mass spectrometer is first ionized in the ionization chamber 2 after being introduced into the sample introduction chamber 1. Further, the ionized sample moves to the ion trap unit 3 where ion accumulation and a mass scan operation for obtaining a mass spectrum are performed.

  And the ion discharge | released from the ion trap part 3 by the mass scan is converted into an electrical signal by the detector 4, and is soft-corrected in the data processing part 5, and a mass spectrum is obtained. The result of the data processing unit 5 is sent to the data output unit 6 so that information on the mass spectrum is displayed on the screen 7.

  In the following, various examples of the ion trap unit 3 that is a feature of the present invention will be described in detail in the present embodiment and further in the following embodiments.

<Ion trap part>
The ion trap part 3 in the mass spectrometer shown in FIG. 1 is demonstrated using FIG. FIG. 2 is a diagram for explaining an example of the configuration of the ion trap unit 3.

  The ion trap unit 3 in the present embodiment includes an RF signal source 201, a rod electrode unit 202, a resonance characteristic measurement unit 203, a control unit 204, and a resonance circuit unit 205.

  The RF signal source 201 is a signal source that generates a high-frequency signal (RF signal). The rod electrode unit 202 includes four rod electrodes 206a-1, 206a-2, 206b-1, and 206b-2 that are arranged in parallel with each other to form a pair. That is, the four rod electrodes 206a-1, 206a-2, 206b-1, 206b-2 are one set of rod electrode pairs 206a-1, 206a-2 (facing to the central axis of the rod electrodes). Hereinafter, the rod electrode pair 206a and the other pair of rod electrode pairs 206b-1 and 206b-2 (hereinafter also simply referred to as the rod electrode pair 206b) are provided.

  The resonance circuit unit 205 is connected between the RF signal source 201 and the rod electrode unit 202, and includes load capacitors 208a and 208b including coils 207a and 207b, rod electrode pairs 206a and 206b, parasitic capacitances of wirings, and the like, and resonance It consists of characteristic adjusting sections 209a and 209b. The resonance characteristic adjustment units 209a and 209b include adjustment elements 210a and 210b and voltage dividing circuits 211a and 211b, respectively.

  In the resonance circuit unit 205, the input side of the voltage dividing circuit 211 a is connected to one end of the RF signal source 201, and the input side of the voltage dividing circuit 211 b is connected to the other end of the RF signal source 201. The output sides of the voltage dividing circuits 211a and 211b are connected to one ends of the coils 207a and 207b, respectively. The other end of each of the coils 207a and 207b is connected to one end of each of the load capacitors 208a and 208b. The other ends of the load capacitors 208a and 208b are grounded.

  The connection node between the other end of the coil 207a and one end of the load capacitor 208a is connected to one rod electrode pair 206a, and the connection node between the other end of the coil 207b and one end of the load capacitor 208b is the other rod electrode pair 206b. It is connected to the. The output side of the control unit 204 is connected to the input side of each of the adjustment elements 210a and 210b.

  The resonance circuit unit 205 resonates and amplifies the RF signal generated by the RF signal source 201 to generate a high-voltage RF signal. The resonance circuit unit 205 generates a high-voltage RF signal in the same phase as one rod electrode pair 206a-1 and 206a-2 of the rod electrode unit 202. A voltage RF signal is applied, and a high voltage RF signal that is different from the high voltage RF signal applied to one rod electrode pair 206a-1 and 206a-2 is applied to the other rod electrode pair 206b-1 and 206b-2. To do.

  The resonance characteristic measurement unit 203 is connected to a connection node between the resonance circuit unit 205 and the rod electrode unit 202, and the resonance frequency of the resonance circuit unit 205 or the amplitude (amplification factor) of the resonance-amplified high-voltage RF signal, or Measure both.

  The control unit 204 is connected between the output side of the resonance characteristic measurement unit 203 and the input side of the adjustment elements 210a and 210b of the resonance characteristic adjustment units 209a and 209b, and has a resonance frequency and amplitude measured by the resonance characteristic measurement unit 203 ( Based on the amplification factor, the adjustment elements 210a and 210b of the resonance characteristic adjustment units 209a and 209b are adjusted. That is, the control unit 204 uses the measurement result of the resonance frequency of the resonance circuit unit 205 or the amplitude (amplification factor) of the high voltage RF signal to generate the high voltage generated by the RF signal source 201 at the resonance frequency of the resonance circuit unit 205. The resonance characteristic adjustment units 209a and 209b are controlled so as to match the driving frequency of the RF signal to correct the frequency deviation between the driving frequency and the resonance frequency.

  The resonance characteristic adjustment units 209a and 209b have a function of matching the driving frequency of the RF signal generated by the RF signal source 201 with the resonance frequency of the resonance circuit unit 205, and the RF signal source 201 and the rod electrode pair. 206a, 206b, more specifically, between the RF signal source 201 and the coils 207a, 207b connected to the rod electrode pair 206a, 206b.

  The resonance characteristic adjustment units 209a and 209b are constituted by voltage dividing circuits 211a and 211b and adjustment elements 210a and 210b. The voltage across the resonance characteristic adjustment units 209a and 209b is a voltage applied to the rod electrode unit 202. More specifically, it is characterized in that it is configured to be smaller than the voltage applied to the rod electrode pair 206a, 206b.

  The voltage dividing circuits 211a and 211b are circuits for making the voltage applied to the adjusting elements 210a and 210b smaller than the high voltage RF signal. The adjustment elements 210a and 210b are configured to be able to adjust the resonance frequency of the resonance circuit unit 205 or the resonance frequency and amplitude (amplification factor). Since the voltage applied to the adjusting elements 210a and 210b is lowered by the voltage dividing circuits 211a and 211b, the components constituting the adjusting elements 210a and 210b do not require high withstand voltage parts. Can be realized.

  In the present embodiment, the voltage dividing circuits 211a and 211b and the adjusting elements 210a and 210b are described separately, but there are some components of the voltage dividing circuits 211a and 211b and the adjusting elements 210a and 210b. Even if they are all configured in common, the same effects as in the present embodiment can be obtained.

<Resonance characteristic measurement unit and control unit>
The resonance characteristic measuring unit 203 and the control unit 204 shown in FIG. 2 will be described with reference to FIG. FIG. 3 is a diagram for explaining an example of the configuration of the resonance characteristic measuring unit 203 and the control unit 204.

  The resonance characteristic measuring unit 203 in the present embodiment includes voltage dividing circuits 301a and 301b, rectifying circuits 302a and 302b, an adder 303, a resonance frequency measuring block 304, and an amplitude measuring block 305. Further, the control unit 204 in the present embodiment includes a resonance frequency control block 306, an amplification factor control block 307, and an RF signal source control block 308.

  In the resonance characteristic measuring unit 203, the input side of the voltage dividing circuit 301a is connected to the rod electrode pair 206a-1 and 206a-2, and the input side of the voltage dividing circuit 301b is connected to the rod electrode pair 206b-1 and 206b-2. Has been. The output sides of the voltage dividing circuits 301a and 301b are connected to the input sides of the rectifier circuits 302a and 302b, respectively. The output sides of the rectifier circuits 302a and 302b are connected to the input sides of the adder 303, respectively. The output side of the adder 303 is connected to the input side of each of the resonance frequency measurement block 304 and the amplitude measurement block 305.

  The output side of the resonance frequency measurement block 304 is connected to the input side of the resonance frequency control block 306 of the control unit 204. The output side of the resonance frequency control block 306 is connected to the input sides of the adjustment elements 210a and 210b of the resonance characteristic adjustment units 209a and 209b. The output side of the amplitude measurement block 305 is connected to the input side of the amplification factor control block 307 of the control unit 204. The output side of the amplification factor control block 307 is connected to the input side of the adjustment elements 210a and 210b of the resonance characteristic adjustment units 209a and 209b.

  The resonance characteristic measuring unit 203 receives and inputs the high voltage RF signals applied to the rod electrode pairs 206a-1, 206a-2 and 206b-1, 206b-2, respectively. The signal branched from the high voltage RF signal applied to 206a-2 is reduced by the voltage dividing circuit 301a, and the signal branched from the high voltage RF signal applied to the pair of rod electrodes 206b-1 and 206b-2 is obtained. The signal amplitude is reduced by the voltage dividing circuit 301b.

  Further, the RF signal whose signal amplitude has been reduced by the voltage dividing circuit 301a is converted into a DC signal by the rectifier circuit 302a, and the RF signal whose signal amplitude has been reduced by the voltage divider circuit 301b is converted to a DC signal by the rectifier circuit 302b. Is converted to The direct current signal converted by the rectifier circuits 302 a and 302 b is input to the adder 303.

  The adder 303 adds the DC signal converted by the rectifier circuit 302a and the DC signal converted by the rectifier circuit 302b, and this added signal is input to the resonance frequency measurement block 304 and the amplitude measurement block 305. The resonance frequency and amplitude are detected from the added signal. Information on the resonance frequency detected by the resonance frequency measurement block 304 is output to the resonance frequency control block 306 of the control unit 204. Further, the amplitude information detected by the amplitude measurement block 305 is output to the amplification factor control block 307 of the control unit 204.

  Further, in the control unit 204, the resonance frequency control block 306 controls the resonance characteristic adjustment units 209a and 209b of the resonance circuit unit 205 based on the resonance frequency information in the resonance frequency measurement block 304 of the resonance characteristic measurement unit 203. On the other hand, the amplification factor control block 307 controls the resonance characteristic adjustment units 209 a and 209 b of the resonance circuit unit 205 based on the amplitude information in the amplitude measurement block 305 of the resonance characteristic measurement unit 203.

<Resonance frequency and gain adjustment procedure>
A procedure for adjusting the resonance frequency and the amplification factor of the resonance characteristic adjusting units 209a and 209b by the resonance characteristic measuring unit 203 and the control unit 204 shown in FIG. 3 will be described with reference to FIG. FIG. 4 is a flowchart for explaining an example of a procedure for adjusting the resonance frequency and the amplification factor of the resonance characteristic adjusting units 209a and 209b.

  When the adjustment is started, first, the RF signal source control block 308 of the control unit 204 changes the driving frequency of the RF signal source 201 while changing the rod electrode pair 206a-1, 206a-2 and 206b-1, 206b at each driving frequency. The high voltage RF signal applied to -2 is branched and input to the resonance characteristic measuring unit 203.

  Then, in the resonance characteristic measuring unit 203, the amplitudes of the signals input by the voltage dividing circuits 301a and 301b are reduced, and the respective signals are converted into DC signals by the rectifier circuits 302a and 302b. Are input to the adder 303 and added. The added signal is input to the resonance frequency measurement block 304, and the driving frequency of the RF signal source 201 when the added signal becomes the largest is detected as the resonance frequency (S1). The detected resonance frequency is input to the control unit 204.

  Further, in the resonance frequency control block 306 of the control unit 204, it is determined whether or not the input resonance frequency is within a predetermined value range (S2). As a result of the determination of the resonance frequency, when the resonance frequency deviates from the predetermined value range (S2-NO), the resonance frequency is adjusted by the resonance characteristic adjusting units 209a and 209b (S3), and the resonance frequency is measured again. (S1). When the resonance frequency is within the predetermined value range (S2-YES), the driving frequency is set by the RF signal source control block 308 (S4).

  Subsequently, in the amplitude measurement block 305 of the resonance characteristic measuring unit 203, the amplitude of the high voltage RF signal applied to the rod electrode pairs 206a-1, 206a-2 and 206b-1, 206b-2 is measured (S5). The measured amplitude is input to the control unit 204.

  Further, in the amplification factor control block 307 of the control unit 204, an amplification factor is obtained from the input amplitude, and it is determined whether or not this amplification factor is within a predetermined value range (S6). As a result of the determination of the amplification factor, when the amplification factor is out of the predetermined value range (S6-NO), the amplification factor is adjusted by the resonance characteristic adjusting units 209a and 209b (S7), and the amplitude is again set. The amplification factor is obtained by measurement (S5). If the amplification factor is within the predetermined value range (S6-YES), the adjustment is terminated.

<Effect of Embodiment 1>
According to the mass spectrometer according to the present embodiment described above, the ion trap unit 3 includes the rod electrode unit 202, the RF signal source 201, the resonance circuit unit 205, the resonance characteristic adjustment units 209a and 209b, and the resonance characteristic measurement unit 203. , The control unit 204 and the like, the resonance characteristic adjustment units 209a and 209b are arranged between the RF signal source 201 and the rod electrode unit 202, and the voltage across the resonance characteristic adjustment units 209a and 209b is the rod electrode unit 202. The following effects can be obtained by being configured so as to be smaller than the voltage applied to.

  The effect of the mass spectrometer according to the present embodiment is that the resonance characteristics can be adjusted in the resonance characteristics adjusting sections 209a and 209b of the ion trap section 3 without using high-voltage components. As a result, the mass spectrometer can be reduced in cost, size, and measurement throughput can be improved.

  That is, since the tuning circuit including the resonance characteristic adjustment units 209a and 209b for correcting the deviation between the drive frequency and the resonance frequency due to element variations, temperature fluctuations, and the like can be configured with low withstand voltage components of about several tens of volts to 100V. The cost and size of the apparatus can be reduced. In addition, since the tuning function can be automated without using mechanical parts, adjustment control and calculation processing are simplified, and stability of the mass spectrometer and measurement throughput are expected to be improved.

[Embodiment 2]
A mass spectrometer according to the present embodiment will be described with reference to FIG. The mass spectrometer according to the present embodiment differs from the first embodiment in the configuration of an ion trap unit (including a resonance characteristic adjustment unit having a specific circuit configuration). Since the configuration of the mass spectrometer according to the present embodiment is the same as that of the first embodiment (FIG. 1), description thereof will be omitted, and the following mainly describes differences from the first embodiment. To do.

<Ion trap part>
FIG. 5 is a diagram for explaining an example of the configuration of the ion trap unit in the mass spectrometer (FIG. 1) according to the second embodiment. In FIG. 5, the last two digits of the 200 series in FIG. 2 are indicated by the same numbers in the 500 series in FIG.

  The ion trap unit in this embodiment includes an RF signal source 501, a rod electrode unit 502 having rod electrodes 506a-1, 506a-2, 506b-1, and 506b-2 (rod electrode pairs 506a and 506b), and resonance characteristic measurement. Part 503, control part 504, and resonance circuit part 505.

  The resonance circuit unit 505 includes resonance characteristics adjusting units 509a and 509b, inductance components of the coils 507a and 507b, wiring parasitic resistances 512a and 512b, and load capacitors 508a and 506b including rod electrode pairs 506a and 506b and wiring parasitic capacitances. 508b. Further, the resonance characteristic adjusting units 509a and 509b are configured only by variable series capacitors 513a and 513b respectively connected between the RF signal source 501 and the coils 507a and 507b.

In this configuration, the capacitance values of the series capacitors 513a and 513b are C _S , the inductance values of the coils 507a and 507b are L, the resistance values of the parasitic resistors 512a and 512b are R, and the capacitance values of the load capacitors 508a and 508b are C _L. The resonance frequency f ₀ of the resonance circuit unit 505, the voltage amplitude V _R of the rod electrode pair 506a, 506b at the resonance frequency f _0, the voltage amplitude V _C between the terminals of the series capacitors 513a, 513b, and the rod electrode pair 506a, 506b and the resonant characteristic adjusting section 509a, the ratio _{D V} of the voltage amplitude of the 509b is expressed by the following equation.

From the above equation, the resonance frequency f ₀ can be adjusted according to (Equation 5) by the series capacitors 513a and 513b. Also, the series capacitor 513a, the voltage _{V C} across the terminals of 513b, the rod electrode pairs 506a, the amplitude _{V R} at 506b, the amount corresponding to the divided value represented by Equation (8).

  With the configuration as described above, in the ion trap unit in the present embodiment, as the same effect as in the first embodiment, a resonance characteristic adjustment unit that corrects a deviation between the drive frequency and the resonance frequency due to element variation, temperature fluctuation, and the like. Since the tuning circuit including 509a and 509b can be configured with a withstand voltage component as low as several tens of volts to 100V, the mass spectrometer can be reduced in cost and size. In addition, since the tuning function can be automated without using mechanical parts, adjustment control and calculation processing are simplified, and stability of the mass spectrometer and measurement throughput are expected to be improved.

  Further, as an effect different from that of the first embodiment, the circuit of the resonance characteristic adjusting units 509a and 509b shown here (configuration of only the variable series capacitors 513a and 513b) adjusts the resonance frequency and also increases the amplification factor ( Varies according to equation 6). As a method for correcting the change in amplification factor, a method of adjusting the output amplitude of the RF signal source 501 by the control unit 504 and compensating for the variation in amplification factor is useful.

[Embodiment 3]
A mass spectrometer according to the present embodiment will be described with reference to FIG. The mass spectrometer according to the present embodiment is different from that of the first embodiment in that the ion trap unit (including a resonance characteristic adjustment unit having a specific circuit configuration capable of independently adjusting the resonance frequency and the amplification factor). The configuration is different. Since the configuration of the mass spectrometer according to the present embodiment is the same as that of the first embodiment (FIG. 1), description thereof will be omitted, and the following mainly describes differences from the first embodiment. To do.

<Ion trap part>
FIG. 6 is a diagram for explaining an example of the configuration of the ion trap unit in the mass spectrometer (FIG. 1) according to the third embodiment. 6, the last two digits of the 200 and 500 series in FIG. 2 and FIG. 5 are indicated by the same numerals in the 600 series in FIG. .

  The ion trap unit in the present embodiment includes an RF signal source 601, a rod electrode unit 602 having rod electrodes 606a-1, 606a-2, 606b-1, and 606b-2 (rod electrode pairs 606a and 606b), and resonance characteristic measurement. A unit 603, a control unit 604, and a resonance circuit unit 605.

  The resonance circuit unit 605 includes resonance characteristics adjusting units 609a and 609b, inductance components of the coils 607a and 607b, wiring parasitic resistances 612a and 612b, and load capacitors 608a and 606b including rod electrode pairs 606a and 606b and wiring parasitic capacitance. 608b. The resonance characteristic adjusting units 609a and 609b include variable series capacitors 613a and 613b connected between the RF signal source 601 and the coils 607a and 607b, one terminal connected to the coils 607a and 607b, and the other terminal. Are constituted by variable parallel capacitors 614a and 614b.

In this configuration, the capacitance value of the series capacitors 613a and 613b is C _S , the capacitance value of the parallel capacitors 614a and 614b is C _P , the inductance value of the coils 607a and 607b is L, and the resistance value of the parasitic resistances 612a and 612b of the wiring is R , load capacitor 608a, placing the capacitance value of 608b and _{C L,} the resonant frequency _{f 0} of the resonance circuit 605, the rod electrode pairs 606a at the resonance frequency _{f 0,} the voltage amplitude _{V R} of 606b, series capacitor 613a, the 613b The voltage amplitude V _C between terminals and the voltage amplitude ratio D _V between the rod electrode pair 606a, 606b and the resonance characteristic adjustment units 609a, 609b are expressed by the following equations.

From the above equation, the resonance frequency f ₀ can be adjusted according to (Equation 9) by the series capacitors 613a and 613b and the parallel capacitors 614a and 614b. Also, the series capacitor 613a, the voltage _{V C} across the terminals of 613b, the rod electrode pairs 606a, the amplitude _{V R} at 606b, the amount corresponding to the divided value represented by Equation (12). For example, series capacitor 613a, the capacity of 613b _{C S} and the parallel capacitor 614a, sum load capacitors 608a of the capacitance _{C P} of 614b, when five times the capacity _{C L} of 608b, series capacitor 613a, between 613b of the terminal voltage _{V C} the rod electrode pairs 606a, the one fifth of the voltage _{V R} at 606b.

  Further, according to the circuit configuration shown here, as shown in (Equation 10), the gain can be adjusted by adjusting any of the variable series capacitors 613a and 613b or the parallel capacitors 614a and 614b. Is possible. In particular, since the amplification factor can be adjusted with the resonance frequency kept constant by making the sum of the capacitances of the series capacitors 613a and 613b and the parallel capacitors 614a and 614b constant and changing the ratio of the capacitances, the resonance frequency and amplification factor can be adjusted. Since adjustment can be performed independently, adjustment control can be expected to be simple.

  From the above, in the ion trap part in the present embodiment, the same effect as in the first embodiment can be obtained, and as an effect different from the first embodiment, the resonance frequency and the amplification factor can be adjusted independently. Therefore, since adjustment control becomes easy, it becomes possible to improve the measurement throughput of the mass spectrometer.

  The circuit configuration (the configuration of the variable series capacitors 613a and 613b and the variable parallel capacitors 614a and 614b) for realizing the resonance characteristic adjustment units 609a and 609b shown here is an example, and the present invention is a resonance characteristic adjustment unit 609a. , 609b are arranged between the RF signal source 601 and the coils 607a and 607b, and the resonance frequency and / or the amplification factor can be adjusted without using high-voltage components. A configuration in which a capacitor is replaced with a coil, or a configuration in which a resonance characteristic adjusting unit is configured by combining a capacitor, a coil, a resistance element, or the like is within the scope of the present invention as long as the same effect can be obtained.

[Embodiment 4]
A mass spectrometer according to the present embodiment will be described with reference to FIG. The mass spectrometer according to the present embodiment has a configuration of an ion trap unit (including a resonant circuit unit configured using a loosely coupled transformer having a coupling ratio of 0.5 or less) compared to the first embodiment. Is different. Since the configuration of the mass spectrometer according to the present embodiment is the same as that of the first embodiment (FIG. 1), description thereof will be omitted, and the following mainly describes differences from the first embodiment. To do.

<Ion trap part>
FIG. 7 is a diagram for explaining an example of the configuration of the ion trap unit in the mass spectrometer (FIG. 1) according to the fourth embodiment. 7, the last two digits of the 200, 500, and 600 series in FIGS. 2, 5, and 6 are 700 in FIG. Shown with the same numbers on the base.

  In the present embodiment, the ion trap unit includes an RF signal source 701, rod electrodes 706a-1, 706a-2, 706b-1, and 706b-2 (rod electrode pairs 706a and 706b), resonance characteristic measurement. A unit 703, a control unit 704, and a resonance circuit unit 705.

  The resonance circuit unit 705 includes a resonance characteristic adjustment unit 709, load capacitors 708 a and 708 b including rod electrode pairs 706 a and 706 b, parasitic capacitance of wiring, and a loosely coupled transformer 715. The loosely coupled transformer 715 has a coupling ratio of 0.5 or less, and includes a primary coil 716a and two secondary coils 716b and 716c. The primary coil 716a is connected to the RF signal source 701, and one of the secondary coils One terminal of 716b is connected to the rod electrode pairs 706a-1 and 706a-2, the other terminal is connected to the resonance characteristic adjusting unit 709, and the one terminal of the other secondary coil 716c is connected to the rod electrode pair 706b-1. 706b-2, the opposite terminals are connected to the resonance characteristic adjusting unit 709, respectively. At this time, the secondary coils 716b and 716c are applied to the adjacent rod electrodes (706a-1 and 706b-1, 706b-1 and 706a-2, 706a-2 and 706b-2, 706b-2 and 706a-1). The polarity is reversed.

  The resonance circuit unit 705 resonantly amplifies the RF signal by the leakage inductance of the secondary coils 716b and 716c of the loosely coupled transformer 715, the load capacitors 708a and 708b, and the resonance characteristic adjustment unit 709. With such a configuration, the voltage applied to both ends of the resonance characteristic adjusting unit 709 is divided by the load capacitors 708a and 708b and the resonance characteristic adjusting unit 709, and becomes smaller than the voltage applied to the rod electrode pair 706a and 706b. .

  From the above, in the ion trap part in the present embodiment, the same effect as in the first embodiment can be obtained, and as an effect different from that in the first embodiment, the resonance circuit unit 705 using the loosely coupled transformer 715. Since the voltage output from the RF signal source 701 can be transformed by adjusting the coupling rate of the loosely coupled transformer 715 and the turns ratio of the primary coil 716a and the secondary coils 716b and 716c, power consumption and It becomes possible to adjust the amplification factor.

[Embodiment 5]
A mass spectrometer according to the present embodiment will be described with reference to FIG. The mass spectrometer according to the present embodiment differs from the first embodiment in the configuration of an ion trap section (having a function of capturing ions and a function of performing mass separation of ions). Since the configuration of the mass spectrometer according to the present embodiment is the same as that of the first embodiment (FIG. 1), description thereof will be omitted, and the following mainly describes differences from the first embodiment. To do.

<Ion trap part>
FIG. 8 is a diagram for explaining an example of the configuration of the ion trap section in the mass spectrometer (FIG. 1) according to the fifth embodiment. In FIG. 8, the components corresponding to those in FIGS. 2, 5, 6, and 7 described above are the bottom 2 in the 200, 500, 600, and 700 series in FIGS. In FIG. 8, the digit numbers are shown by the same numbers in the 800s.

  FIG. 8 illustrates only the circuit configuration of one of the rod electrode pairs 806a-1 and 806a-2 among the rod electrode pairs 806a-1 and 806a-2 and 806b-1 and 806b-2.

  The ion trap unit in the present embodiment includes an RF signal source 801, a rod electrode unit 802 having rod electrodes 806a-1, 806a-2, 806b-1, and 806b-2, a resonance characteristic measuring unit 803, a control unit 804, and In addition to the configuration of the resonance circuit unit 805, an auxiliary AC signal source 819 and the like are provided. The circuit configuration of the other rod electrode pair 806b-1, 806b-2 (not shown in FIG. 8) is from a resonance circuit unit 805 having the same configuration as that of the illustrated rod electrode pair 806a-1, 806a-2. Thus, there is no auxiliary AC signal source 819, and this portion is grounded. In the following, the circuit configuration of one of the rod electrode pairs 806a-1 and 806a-2 illustrated in FIG. 8 will be mainly described.

  The resonance circuit unit 805 includes rod capacitors 806 a-1 and 806 a-2, load capacitors 808 a and 808 b including parasitic capacitance of wiring, and a loosely coupled transformer 815. The loosely coupled transformer 815 includes a primary coil 816a and two secondary coils 816b and 816c. The primary coil 816a is connected to the RF signal source 801, and one terminal of the secondary coil 816b is a rod electrode 806a- 1, the opposite terminal is connected to the resonance characteristic adjustment unit 809, the other terminal of the other secondary coil 816 c is connected to the rod electrode 806 a-2, and the opposite terminal is connected to the resonance characteristic adjustment unit 809. The

  The ion trap portion in the present embodiment has a function of capturing ions and a function of mass separation of ions, and has two pairs of rod electrode pairs 806a-1, 806a-2 and 806b-1, 806b-2. An AC signal (hereinafter referred to as an auxiliary AC signal) is applied to each of the rod electrodes 806a-1 and 806a-2 along with the high voltage RF signal to the pair of rod electrodes 806a-1 and 806a-2 on one side. Further, the auxiliary AC signal applied to the rod electrodes 806a-1 and 806a-2 is configured to be differential.

  The resonance characteristic adjusting unit 809 when used in such an ion trap unit includes variable adjusting capacitors 817a and 817b and a tightly coupled transformer 818. The tightly coupled transformer 818 is more tightly coupled (having a higher coupling ratio) than the loosely coupled transformer 815, and adjustment capacitors 817a and 817b are connected between the terminals of the primary coil and the secondary coil, respectively, and the adjustment capacitors 817a and 817b are respectively connected. Is connected to the auxiliary AC signal source 819, and the other end is connected to terminals on the opposite side of the secondary coils 816b and 816c of the loosely coupled transformer 815. Here, it is desirable that the in-phase impedance of the tightly coupled transformer 818 be higher than the impedance of the adjusting capacitors 817a and 817b at the driving frequency of the RF signal source 801.

  The tightly coupled transformer 818 is connected so that the impedance is low when a differential signal is input and the impedance is high when a common-mode signal is input. When an auxiliary AC signal is input from the auxiliary AC signal source 819 to the resonance characteristic adjustment unit 809, the impedance of the resonance characteristic adjustment unit 809 is lowered by the tightly coupled transformer 818, and is not affected by the resonance characteristic adjustment unit 809. It is transmitted to the coupling transformer 815.

  On the other hand, the signal output from the RF signal source 801 is transmitted to the resonance characteristic adjustment unit 809 via the loosely coupled transformer 815. At this time, since the RF signal input to the resonance characteristic adjustment unit 809 is an in-phase signal, the impedance of the tightly coupled transformer 818 constituting the resonance characteristic adjustment unit 809 is increased, and thus is affected by the adjustment capacitors 817a and 817b. It becomes like this.

  As described above, the auxiliary AC signal from the auxiliary AC signal source 819 and the RF signal from the RF signal source 801 are superimposed by the loosely coupled transformer 815, and the resonance characteristic adjusting unit 809 is connected to the auxiliary AC signal source 819 and the loosely coupled transformer. 815 is configured such that the voltage at both ends of the resonance characteristic adjustment unit 809 is smaller than the voltage applied to the rod electrode pairs 806a-1 and 806a-2.

  From the above, in the ion trap unit in the present embodiment, the same effect as in the first embodiment can be obtained, and as an effect different from that in the first embodiment, the resonance characteristic adjusting unit 809 has the resonance of the RF signal. Only the resonance characteristics of the RF signal are adjusted in the ion trap part that has the function of trapping ions and the function of mass separation of ions since it affects only the characteristics and does not affect the resonance characteristics of the auxiliary AC signal. It becomes possible to do.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say. For example, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. . Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

DESCRIPTION OF SYMBOLS 1 ... Sample introduction chamber, 2 ... Ionization chamber, 3 ... Ion trap part, 4 ... Detector, 5 ... Data processing part, 6 ... Data output part, 7 ... Screen,
201,501,601,701,801,901 ... RF signal source 202,502,602,702,802,902 ... rod electrode part 203,503,603,703,803 ... resonance characteristic measuring part 204,504,604 704, 804 ... Control unit 205, 505, 605, 705, 805, 905 ... Resonance circuit unit 206 (a-1, a-2, b-1, b-2), 506 (a-1, a-2, b-1, b-2), 606 (a-1, a-2, b-1, b-2), 706 (a-1, a-2, b-1, b-2), 806 (a -1, a-2, b-1, b-2), 906 (a-1, a-2, b-1, b-2) ... rod electrodes 207 (a, b), 507 (a, b) , 607 (a, b), 907 (a, b)... Coil 208 (a, b), 508 (a, b), 608 (a , B), 708 (a, b), 808 (a, b), 908 (a, b), 909 ... load capacitors 209 (a, b), 509 (a, b), 609 (a, b), 709, 809 ... Resonance characteristic adjustment unit 210 (a, b) ... Adjustment element 211 (a, b) ... Voltage divider circuit 301 (a, b) ... Voltage divider circuit 302 (a, b) ... Rectifier circuit 303 ... Adder 304 ... Resonance frequency measurement block 305 ... Amplitude measurement block 306 ... Resonance frequency control block 307 ... Amplification factor control block 308 ... RF signal source control block 512 (a, b), 612 (a, b) ... Parasitic resistance 513 (a, b), 613 (a, b) ... Series capacitors 614 (a, b) ... Parallel capacitors 715, 815 ... Loosely coupled transformers 716 (a), 816 (a) ... Primary coils 716 (b, c), 816 (b) , C) Secondary coil 817 (a, b) ... tuning capacitors 818 ... tightly coupled transformer 819 ... auxiliary AC signal source

Claims (12)

A mass spectrometer equipped with an ion trap that separates a sample according to the mass of ions,
The ion trap part is
A rod electrode portion comprising four rod electrodes arranged in parallel to each other;
An RF signal source for generating an RF signal;
A high voltage RF signal is generated by resonance amplification of the RF signal generated by the RF signal source, and is applied to one set of rod electrodes facing the central axis of the four rod electrodes of the rod electrode portion. A resonance circuit unit that applies a high-voltage RF signal and applies a high-voltage RF signal that is different from the high-voltage RF signal applied to the one set of rod electrode pairs to the other set of rod electrode pairs;
A resonance characteristic adjustment unit for adjusting the characteristic of the resonance circuit unit;
Resonance frequency and amplification factor of the resonance circuit section between the high voltage RF signal applied to the one set of rod electrode pairs and the differential high voltage RF signal applied to the other set of rod electrode pairs. A resonance characteristic measurement unit to be measured;
A control unit that adjusts the resonance characteristic adjustment unit based on information on a resonance frequency and an amplification factor of the resonance circuit unit measured by the resonance characteristic measurement unit;
The resonance characteristic adjustment unit is disposed between the RF signal source and the rod electrode unit, and is configured such that a voltage at both ends of the resonance characteristic adjustment unit is smaller than a voltage applied to the rod electrode unit. A mass spectrometer characterized by comprising: The mass spectrometer according to claim 1,
The resonance characteristic adjustment unit includes first and second resonance characteristic adjustment units respectively connected to coils respectively connected to the one set or the other set of rod electrode pairs.
Each of the first and second resonance characteristic adjusting units is composed of a variable capacitor, and the variable capacitor includes a coil connected to the RF signal source and the one set or one set of rod electrode pairs. A mass spectrometer connected between the two. The mass spectrometer according to claim 1,
The resonance characteristic adjustment unit includes first and second resonance characteristic adjustment units respectively connected to coils respectively connected to the one set or the other set of rod electrode pairs.
Each of the first and second resonance characteristic adjusting units is composed of two variable capacitors, and one variable capacitor is connected to the RF signal source and the one set or one set of rod electrode pairs. The mass spectrometer is connected between the other coil and the other variable capacitor is connected between the coil and a ground potential. The mass spectrometer according to claim 1,
The resonance characteristic measurement unit includes:
First and second voltage dividing circuits for reducing the signal amplitude of each signal branched from the high-voltage RF signal applied to the one set or the other set of rod electrode pairs;
First and second rectifier circuits for converting RF signals whose signal amplitude has been reduced by the first and second voltage dividing circuits into DC signals, respectively;
An adder for adding the DC signals converted by the first and second rectifier circuits;
A resonance frequency measurement block for detecting a resonance frequency from the addition signal added by the adder;
A mass spectrometer comprising: an amplitude measurement block that detects an amplitude from the addition signal added by the adder. The mass spectrometer according to claim 4,
The controller is
A resonance frequency control block that controls the resonance characteristic adjustment unit based on resonance frequency information in the resonance frequency measurement block;
An amplification factor control block for controlling the resonance characteristic adjustment unit based on amplitude information in the amplitude measurement block;
A mass spectrometer comprising an RF signal source control block for controlling the RF signal source. The mass spectrometer according to claim 1,
A sample introduction chamber for introducing the sample;
An ionization chamber for ionizing the sample introduced into the sample introduction chamber;
The ion trap part for separating the sample ionized in the ionization chamber according to the mass of the ions;
A detector for detecting ions having a predetermined mass among the ions separated by the ion trap unit;
A mass spectrometer comprising: a data processing unit that processes data obtained by detecting the ions with the detector. A mass spectrometer equipped with an ion trap that separates a sample according to the mass of ions,
The ion trap part is
A rod electrode portion comprising four rod electrodes arranged in parallel to each other;
An RF signal source for generating an RF signal;
A high voltage RF signal is generated by resonance amplification of the RF signal generated by the RF signal source, and is applied to one set of rod electrodes facing the central axis of the four rod electrodes of the rod electrode portion. A resonance circuit unit that applies a high-voltage RF signal and applies a high-voltage RF signal that is different from the high-voltage RF signal applied to the one set of rod electrode pairs to the other set of rod electrode pairs;
A resonance characteristic adjustment unit for adjusting the characteristic of the resonance circuit unit;
An auxiliary AC signal source that applies a differential auxiliary AC signal different from the frequency of the high-voltage RF signal to the one set of rod electrode pairs;
Resonance frequency and amplification factor of the resonance circuit section between the high voltage RF signal applied to the one set of rod electrode pairs and the differential high voltage RF signal applied to the other set of rod electrode pairs. A resonance characteristic measurement unit to be measured;
A control unit that adjusts the resonance characteristic adjustment unit based on information on a resonance frequency and an amplification factor of the resonance circuit unit measured by the resonance characteristic measurement unit;
A first transformer is disposed between the auxiliary AC signal source and the RF signal source and the one set of rod electrode pairs, and the auxiliary AC signal and the RF signal are superimposed by the first transformer; and The resonance characteristic adjusting unit is disposed between the auxiliary AC signal source and the first transformer, and a voltage at both ends of the resonance characteristic adjusting unit is configured to be smaller than a voltage applied to the rod electrode unit. The mass spectrometer characterized by being made. The mass spectrometer according to claim 7, wherein
The resonance characteristic adjusting unit includes a second transformer that is more tightly coupled than the first transformer, and first and second variable capacitors connected between terminals of a primary coil and a secondary coil of the second transformer, respectively. One end of the first and second variable capacitors is connected to the auxiliary AC signal source, and the other end of the first and second variable capacitors is connected to a terminal of the secondary coil of the first transformer. A mass spectrometer characterized by that. The mass spectrometer according to claim 7, wherein
The resonance characteristic measurement unit includes:
First and second voltage dividing circuits for reducing the signal amplitude of each signal branched from the high-voltage RF signal applied to the one set or the other set of rod electrode pairs;
First and second rectifier circuits for converting RF signals whose signal amplitude has been reduced by the first and second voltage dividing circuits into DC signals, respectively;
An adder for adding the DC signals converted by the first and second rectifier circuits;
A resonance frequency measurement block for detecting a resonance frequency from the addition signal added by the adder;
A mass spectrometer comprising: an amplitude measurement block that detects an amplitude from the addition signal added by the adder. The mass spectrometer according to claim 9,
The controller is
A resonance frequency control block that controls the resonance characteristic adjustment unit based on resonance frequency information in the resonance frequency measurement block;
An amplification factor control block for controlling the resonance characteristic adjustment unit based on amplitude information in the amplitude measurement block;
A mass spectrometer comprising an RF signal source control block for controlling the RF signal source. The mass spectrometer according to claim 7, wherein
A sample introduction chamber for introducing the sample;
An ionization chamber for ionizing the sample introduced into the sample introduction chamber;
The ion trap part for separating the sample ionized in the ionization chamber according to the mass of the ions;
A detector for detecting ions having a predetermined mass among the ions separated by the ion trap unit;
A mass spectrometer comprising: a data processing unit that processes data obtained by detecting the ions with the detector. A method for adjusting a mass spectrometer equipped with an ion trap that separates a sample according to the mass of ions,
The ion trap part is
A rod electrode portion comprising four rod electrodes arranged in parallel to each other;
An RF signal source for generating an RF signal;
A high voltage RF signal is generated by resonance amplification of the RF signal generated by the RF signal source, and is applied to one set of rod electrodes facing the central axis of the four rod electrodes of the rod electrode portion. A resonance circuit unit that applies a high-voltage RF signal and applies a high-voltage RF signal that is different from the high-voltage RF signal applied to the one set of rod electrode pairs to the other set of rod electrode pairs;
A resonance characteristic adjustment unit for adjusting the characteristic of the resonance circuit unit;
Resonance frequency and amplification factor of the resonance circuit section between the high voltage RF signal applied to the one set of rod electrode pairs and the differential high voltage RF signal applied to the other set of rod electrode pairs. A resonance characteristic measurement unit to be measured;
A control unit that adjusts the resonance characteristic adjustment unit based on information on a resonance frequency and an amplification factor of the resonance circuit unit measured by the resonance characteristic measurement unit;
The adjustment procedure of the resonance frequency and the amplification factor is as follows:
In the control unit, while changing the driving frequency of the RF signal source, the high voltage RF signals applied to the one pair of rod electrodes and the other pair of rod electrodes at each driving frequency are branched and the resonance Input to the characteristic measurement section,
In the resonance characteristic measuring unit, the amplitude of each input signal is reduced, each signal is converted into a DC signal, the converted DC signal is added, and the RF signal when the added signal becomes the largest The drive frequency of the source is detected as a resonance frequency and input to the control unit,
In the control unit, it is determined whether or not the input resonance frequency is within a predetermined value range. As a result of the determination of the resonance frequency, if the resonance frequency is out of the predetermined value range, the resonance characteristic adjusting unit is Adjust, measure the resonance frequency again, and if the resonance frequency is within the range of the predetermined value, set the drive frequency,
Subsequently, in the resonance characteristic measurement unit, the amplitude of the high voltage RF signal applied to the one set of rods and the other set of rod electrode pairs is measured and input to the control unit,
The control unit obtains an amplification factor from the input amplitude, determines whether the amplification factor is within a predetermined value range, and as a result of the determination of the amplification factor, the amplification factor deviates from the predetermined value range. In this case, the resonance characteristic adjusting unit is adjusted, the amplitude is measured again to obtain the amplification factor, and the adjustment is terminated when the amplification factor is within a predetermined value range. Adjustment method.

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