CN114864371A - Detection method and device for reflection type time-of-flight mass spectrometer - Google Patents
Detection method and device for reflection type time-of-flight mass spectrometer Download PDFInfo
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Abstract
The invention relates to a method and a device for detecting a reflection type time-of-flight mass spectrometer, wherein the device comprises: the ion detection area, detect positive pole switching circuit, preamplification circuit, ADC data acquisition system and host computer, the ion detection area includes first microchannel plate, the second microchannel plate, first detection positive pole, the second detects the positive pole, first microchannel plate, the second microchannel plate is installed along the first direction, first detection positive pole, the second detects the positive pole and installs along the second direction, first detection positive pole, second detection positive pole and second microchannel plate, detect positive pole switching circuit connection, preamplification circuit and detection positive pole switching circuit, ADC data acquisition system connects, ADC data acquisition system and host computer connection. Compared with the prior art, the method can calculate the ion count value to be measured more accurately and conveniently, and avoid the problem of pulse signal saturation in a TDC acquisition mode; the attenuation degree of the detection device can be calculated more accurately and conveniently, and the service life of the detection device can be estimated, and the preparation of a preparation piece can be facilitated.
Description
Technical Field
The invention relates to the technical field of mass spectrometers, in particular to a reflection type time-of-flight mass spectrometer detection method and a device.
Background
The mass spectrometer is a scientific instrument for analyzing chemical substance components, and the working mode of the mass spectrometer is to ionize substances by a certain means and then to sieve charged particles for determination by the mass analyzer. The principle of a time-of-flight mass spectrometer (TOF-MS) is to repel and accelerate ions, so that the ions enter a flight tube (field-free flight zone), and the time of reaching a detector is different according to the different flight speeds of the ions with different mass-to-charge ratios, thereby realizing the purpose of component analysis.
The signal processing system of the time-of-flight mass spectrometer is a very important part of the mass spectrometer, and most of TOF-MS on the market at present adopt a time-to-digital converter (TDC), and the acquisition of signal intensity is realized by counting ions arriving at a detector. However, when the concentration of the detection substance is large, a phenomenon occurs in which a plurality of ions reach the detector at the same time in a short time, and the detector may consider that there is only one ion, which causes a large error. And the dynamic range of an analog-digital converter (ADC) is wider, and the shape of an analog signal output by the ion detector can be accurately recorded.
If the ADC is used as a data acquisition mode, the acquired data is presented in the form of voltage intensity, which is different from the presentation form of pulse count commonly used in commercial instruments at present, and it is necessary to convert the data acquired by the ADC into pulse count in order to make the signal processing system more versatile. Therefore, the invention designs a detection device and a detection method of a reflection type time-of-flight mass spectrometer, which adopt an ADC data acquisition mode to improve the detection dynamic range, and convert an analog signal acquired by an ADC into a pulse counting signal with higher universality by a high-precision calibration method.
Disclosure of Invention
To achieve the above objects and other advantages in accordance with the present invention, a first object of the present invention is to provide a reflection type time-of-flight mass spectrometer detection method, comprising the steps of:
calculating V 2 A voltage value;
to pulse repulsion zone V 2 V calculated by application ratio 2 The voltage value is lower than the voltage in the preset range and is increased to be larger than the calculated V by the preset step length 2 Searching voltage to enable the signal detected by the first detection anode to be highest, recording the signal detected by the first detection anode as a first signal when ions exceeding a first quantity threshold value impact on the first detection anode, and calculating the peak integral value of a plurality of groups of analog signal values in the first signal;
increase V 2 Searching voltage to enable the signal detected by the second detection anode to be highest, obtaining the signal detected by the first detection anode through multiple pulse repulsion and recording the signal as a second signal when ions lower than a second number threshold value are knocked onto the first detection anode, and calculating the peak integral value of a plurality of groups of analog signal values in the second signal;
carrying out maximum common factor calculation on peak integral values of a plurality of groups of analog signal values in the second signal, wherein the obtained maximum common factor is a peak integral value formed by one ion;
and dividing the peak integral value of a plurality of groups of analog signal values in the first signal by the peak integral value formed by one ion to obtain the counting value of the ion.
Further, still include:
increase V 2 A voltage value, calculating a peak integral value of a signal detected by the first detection anode in real time, the peak integral value being in direct relation to the number of ions striking the detection anodeIs a step of;
calculating the ratio of the number of ions falling to the first detection anode region to the total number of ions a%, the ratio of the number of ions falling to the second detection anode region to the total number of ions a%/(1-a%), and the peak integrated value x of the signal detected by the first detection anode region to the peak integrated value y of the signal detected by the second detection anode region at that time, from the decay multiple of the peak integrated value of the first detection anode region;
judging whether x/y is equal to a%/(1-a%), if not, then the magnification of the second detection anode area is the magnification of the first detection anode area
Doubling;
decrease V 2 Voltage value, detecting signal value on the second detection anode, calculating peak integral value and maximum common factor of multiple groups of signals in the second detection anode area, wherein the obtained maximum common factor is single ion peak integral value z in the second detection anode area 1 ；
Calculating the peak integral value z formed by single ions in the first detection anode area according to the difference multiple n between the magnification of the first detection anode area and the magnification of the second detection anode area 2 ＝z 1 /n；
And calculating an ion count value of the first detection anode region through a peak integral value of a signal detected by the first detection anode region and a single-ion peak integral value of the first detection anode region.
Further, V is calculated according to a reflection type flight time formula 2 Voltage value, the formula of the reflection type flight time is as follows:
wherein E is 1 、E 2 、E 3 、E 4 The electric field intensity of the pulse repulsion region, the acceleration region, the first reflection region and the second reflection region，l 1 、l 2 、l 3 、l 4 L is the length of the ion from the exit of the pulse repulsion area, the length of the acceleration area, the length of the first reflection area, the length of the second reflection area and the length of the field-free flight area, and d is the distance between the center of the repulsion area and the center of the first detection anode.
Further, the preset range is 20V-30V; the preset stepping length is 1V; the peak integral value is the integral of the ion current intensity on the time axis.
A second object of the present invention is to provide a reflective time-of-flight mass spectrometer detection apparatus comprising: the ion detection area comprises a first microchannel plate, a second microchannel plate, a first detection anode and a second detection anode, the first microchannel plate and the second microchannel plate are installed along a first direction, the first detection anode and the second detection anode are installed along a second direction, the first detection anode and the second detection anode are connected with the second microchannel plate and the detection anode switching circuit, the preamplification circuit is connected with the detection anode switching circuit and the ADC data acquisition system, the ADC data acquisition system is connected with the upper computer, the detection anode switching circuit is used for switching the first detection anode and the second detection anode, and the preamplification circuit is used for switching the first detection anode and the second detection anode, The current signal output by the second detection anode is converted into a voltage signal and amplified, the ADC data acquisition system is used for data acquisition and data transmission, and the upper computer is used for processing and calculating the acquired data.
Further, the detection anode switching circuit includes a first coupling capacitor, a second coupling capacitor and a switch, the first coupling capacitor is connected to the first detection anode, the second coupling capacitor is connected to the second detection anode, and the switch is connected to the first coupling capacitor, the second coupling capacitor and the pre-amplification circuit.
Further, the pre-amplification circuit comprises a current-voltage conversion circuit and a voltage amplification circuit, the current-voltage conversion circuit is connected with the voltage amplification circuit and the switch, the current-voltage conversion circuit is used for converting current signals output by the first detection anode and the second detection anode into voltage signals, and the voltage amplification circuit is used for amplifying the voltage signals converted by the current-voltage conversion circuit.
Further, ADC data acquisition system includes ADC acquisition chip, FPGA chip, memory, ADC acquisition chip the memory the host computer with the FPGA chip is connected, ADC acquisition chip with preamplification circuit connection, ADC acquisition chip is used for converting analog voltage signal into digital signal, the FPGA chip is used for the collection and the data transmission of control data, the memory is used for the data of temporary storage collection return.
Further, the first microchannel plate and the second microchannel plate are installed along a Y axis, the first detection anode and the second detection anode are installed along an X axis, the X axis is parallel to a polar plate in the reflection type time-of-flight mass spectrometer, and the Y axis is perpendicular to the polar plate in the reflection type time-of-flight mass spectrometer.
Further, an inlet polar plate of the ion detection area is of a grid structure with the transmittance of more than 90%.
Compared with the prior art, the invention has the beneficial effects that:
the invention provides a method and a device for detecting a reflection type time-of-flight mass spectrometer, which can more accurately and conveniently calculate the count value of ions to be detected compared with the prior art and avoid the problem of pulse signal saturation in a TDC (time-of-flight digital converter) acquisition mode; the invention can more accurately and conveniently calculate the attenuation degree of the detection device, and is beneficial to estimating the service life of the detection device and preparing a preparation in advance; the auxiliary detection anode of the present invention can be used as a substitute for the main detection anode after the main detection anode is partially damaged.
The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood and to implement them in accordance with the contents of the description, the following detailed description is given with reference to the preferred embodiments of the present invention and the accompanying drawings. The detailed description of the present invention is given in detail by the following examples and the accompanying drawings.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:
FIG. 1 is a schematic diagram I of a reflection type time-of-flight mass spectrometer and a detection device thereof in example 1;
FIG. 2 is a schematic diagram II of a reflection type time-of-flight mass spectrometer and a detection device thereof in example 1;
FIG. 3 is a schematic diagram showing the connection of the anode, the anode switching circuit and the pre-amplifier circuit in embodiment 1;
FIG. 4 is a schematic diagram of an ADC data acquisition system of embodiment 1;
FIG. 5 is a schematic diagram of the repulsive voltage according to example 1;
FIG. 6 is a schematic diagram of the detection method of the reflection type time-of-flight mass spectrometer of example 2;
FIG. 7 is a schematic of integration of peak intensity;
FIG. 8 is a schematic diagram of the detection method of the reflection type time-of-flight mass spectrometer of example 3;
fig. 9 is a schematic diagram illustrating the calibration of the magnification of the main detection anode region and the sub detection anode region in example 3.
Detailed Description
The present invention will be further described with reference to the accompanying drawings and the detailed description, and it should be noted that any combination of the embodiments or technical features described below can be used to form a new embodiment without conflict.
Example 1
A reflective time-of-flight mass spectrometer detection device, as shown in fig. 1 and 2, comprising: ion detection area, detection positive pole switching circuit, preamplification circuit, ADC data acquisition system and host computer, ion detection area include first microchannel plate, second microchannel plate, first detection positive pole, second detection positive pole, and in this embodiment, first detection positive pole is as main detection positive pole, and the second detects the positive pole as vice detection positive pole. The first microchannel plate and the second microchannel plate are installed along a first direction, the first detection anode and the second detection anode are installed along a second direction, the first detection anode and the second detection anode are connected with the second microchannel plate and the detection anode switching circuit, the preamplifier circuit is connected with the detection anode switching circuit and the ADC data acquisition system, the ADC data acquisition system is connected with an upper computer, the detection anode switching circuit is used for switching the first detection anode and the second detection anode, the preamplifier circuit is used for converting current signals output by the first detection anode and the second detection anode into voltage signals and amplifying the voltage signals, the ADC data acquisition system is used for data acquisition and data transmission, and the upper computer is used for processing and calculating acquired data.
As shown in fig. 3, the anode detection switching circuit includes a first coupling capacitor, a second coupling capacitor and a switch, the first coupling capacitor is connected to the first anode detection, the second coupling capacitor is connected to the second anode detection, and the switch is connected to the first coupling capacitor, the second coupling capacitor and the preamplifier circuit.
The preamplification circuit comprises a current-voltage conversion circuit and a voltage amplification circuit, wherein the current-voltage conversion circuit is connected with the voltage amplification circuit and the change-over switch, the current-voltage conversion circuit is used for converting current signals output by the first detection anode and the second detection anode into voltage signals, such as can be realized through a sampling resistor, and the voltage amplification circuit is used for amplifying voltage signals converted by the current-voltage conversion circuit, such as can be realized through an operational amplifier.
As shown in fig. 4, the ADC data acquisition system includes an ADC acquisition chip, an FPGA chip, and a memory, where the ADC acquisition chip, the memory, and the upper computer are connected to the FPGA chip, the ADC acquisition chip is connected to the preamplifier circuit, the ADC acquisition chip is used to convert analog voltage signals into digital signals, the FPGA chip is used to control data acquisition and data transmission, and the memory is used to temporarily store the acquired data.
In this embodiment, first microchannel plate, second microchannel plate are installed along the Y axle, and first detection positive pole, second detection positive pole are installed along the X axle, and the X axle is parallel with polar plate in the reflection type time of flight mass spectrograph, and the Y axle is perpendicular with polar plate in the reflection type time of flight mass spectrograph.
Preferably, the static repulsion polar plate, the negative pulse repulsion polar plate, the acceleration zone outlet polar plate, the first reflection zone inlet polar plate, the second reflection zone inlet polar plate and the ion detection zone inlet polar plate are all grid mesh structures with the transmittance of more than 90%. The grid structure can make the electric field more even, and the electric field of each region does not influence each other because the grid separation.
As shown in FIG. 5, V is first applied to the positive pulse repulsion plate 2 To V 1 Applying a voltage V to the negative pulse repulsion electrode plate 2 To V 3 Applying a voltage V to the static repulsion electrode 2 Static voltage, V applied to exit plate of acceleration region 4 A static voltage. When the ion current enters the pulse repulsion zone, due to V 2 Has a certain velocity in the X direction, and the velocity magnitude and V are 2 The voltage value has a certain relation, and at a certain moment, the voltage on the positive pulse repulsion polar plate is changed into V 1 The voltage on the negative pulse repulsion polar plate becomes V 3 At the moment, the ion current is subjected to the force of an electric field in the Y direction, the ions have an acceleration and fly into an acceleration area along the Y direction, the ions are accelerated in the acceleration area and enter a field-free flight area, the ions are reflected back by an electrostatic field in a reflection area, and the falling points of the ions reflected back are changed due to the speed in the X direction and reach a detection area, so that the ion detection is realized.
Example 2
A reflective time-of-flight mass spectrometer detection method, which is a correction method for converting data collected by an ADC collection chip into pulse counts, as shown in fig. 6, and includes the following steps:
s11, first calculate V 2 A voltage value; in this embodiment, V is calculated according to the formula of reflective time-of-flight 2 The voltage value, the reflection type flight time formula is:
wherein E is 1 、E 2 、E 3 、E 4 The electric field intensity of the pulse repulsion zone, the acceleration zone, the first reflection zone and the second reflection zone respectively,/ 1 、l 2 、l 3 、l 4 L is the length of the ion from the exit of the pulse repulsion area, the length of the acceleration area, the length of the first reflection area, the length of the second reflection area and the length of the field-free flight area, and d is the distance between the center of the repulsion area and the center of the first detection anode.
S12, pulse repulsion zone V 2 V calculated by application ratio 2 The voltage value is lower than the voltage in the preset range of 20V-30V and is increased to be larger than the calculated V by the preset step length of 1V 2 The voltage value is higher than the voltage in a preset range such as 20V-30V, the voltage is searched to enable the signal detected by the first detection anode to be the highest, at the moment, the repelled ions almost all hit the anode area of the main detector, at the moment, all ion pulse signals are superposed together to form an analog signal peak, and the number of the ions cannot be analyzed; obtaining a signal detected by the first detection anode when ions exceeding a first quantity threshold value, such as 100%, hit the first detection anode, recording the signal as a first signal, and calculating a peak integral value of a plurality of groups of analog signal values in the first signal; as shown in fig. 7, the peak integration value is the integral of the ion current intensity on the time axis, that is, the absolute value of the signal caused by all ions in a certain time.
S13, then increasing V 2 Voltage value, at this time with V 2 Increasing the numerical value, gradually approaching the drop point of the ion flow on the microchannel plate from the main detection anode to the auxiliary detection anode, searching voltage to enable the signal detected by the second detection anode to be highest, when the signal detected by the auxiliary detection anode is highest, more than 90% of ions are impacted on the auxiliary detection anode, few ions which are impacted on the main detection anode at the moment are even single-digit, through multiple pulse repulsion, obtaining the signal which is lower than a second number threshold value, such as 10%, when the ions are impacted on the first detection anode, the signal detected by the first detection anode, and the signal detected by the main detection anode is the analog signal value obtained by a plurality of groups of ions which are few, marking the analog signal value as a second signal, calculating the analog signal valuePeak integral values of a plurality of sets of analog signal values in the second signal;
s14, calculating the greatest common factor of the peak integral values of a plurality of groups of analog signal values in the second signal, wherein the obtained greatest common factor is the peak integral value formed by one ion; and the more the repulsion pulses, the more accurate the resulting data.
S15, dividing the peak integral value of the analog signal values in the first signal by the peak integral value formed by one ion to obtain the ion count value.
Example 3
A method for detecting a reflection type time-of-flight mass spectrometer, which is a correction method for converting data collected by an ADC collecting chip into pulse counts, as shown in fig. 8, includes the following steps:
s21, first calculate V 2 A voltage value; in this embodiment, V is calculated according to the formula of reflective time-of-flight 2 The voltage value, the reflection type flight time formula is:
wherein E is 1 、E 2 、E 3 、E 4 The electric field intensity of the pulse repulsion zone, the acceleration zone, the first reflection zone and the second reflection zone respectively,/ 1 、l 2 、l 3 、l 4 L is the length of the ion from the exit of the pulse repulsion area, the length of the acceleration area, the length of the first reflection area, the length of the second reflection area and the length of the field-free flight area, and d is the distance between the center of the repulsion area and the center of the first detection anode.
S22, pulse repulsion zone V 2 V calculated by application ratio 2 The voltage value is lower than the voltage in the preset range of 20V-30V and is increased to be larger than the calculated V by the preset step length of 1V 2 The voltage value is higher than the voltage in the preset range such as 20V-30V, the voltage is searched to ensure that the signal detected by the first detection anode is the highest, at the moment, the repelled ions almost all hit the anode area of the main detector, at the moment, all ion pulse signals are superposed together to form an analog signal peak, and no analog signal peak existsThe number of ions is analyzed by the method; obtaining a signal detected by the first detection anode when ions exceeding a first quantity threshold value, such as 100%, hit the first detection anode, recording the signal as a first signal, and calculating a peak integral value of a plurality of groups of analog signal values in the first signal; as shown in fig. 7, the peak integration value is the integral of the ion current intensity on the time axis, that is, the absolute value of the signal caused by all ions in a certain time.
As shown in fig. 9, the amplification factors of the main detection anode region and the sub detection anode region are then calibrated, and the specific steps are as follows:
s23, then increasing V 2 The voltage value enables the falling point of ions on the microchannel plate to lean against the auxiliary detection anode area from the main detection anode area, ions detected by the main detection anode slowly decrease at the moment, ions detected by the auxiliary detection anode slowly increase, the peak integral value of a signal detected by the first detection anode is calculated in real time, the peak integral signal detected by the main detection anode slowly attenuates at the moment, and the peak integral value is in a direct proportion relation with the number of ions striking the detection anode;
s24, calculating the ratio of the number of ions falling to the first detection anode region to the total number of ions a%, the ratio of the number of ions falling to the second detection anode region to the total number of ions a%/(1-a%), and the peak integrated value x of the signal detected by the first detection anode region to the peak integrated value y of the signal detected by the second detection anode region at that time, based on the decay multiple of the peak integrated value of the first detection anode region;
s25, judging whether x/y is equal to a%/(1-a%), if not, indicating that the magnification of the two detection areas is different, and at the moment, the magnification of the second detection anode area is the magnification of the first detection anode area
Doubling;
s26, decreasing V 2 Voltage value, the ion current falling point on the micro-channel plate moves from the auxiliary detection area to the main detection area, and the ion falling point is adjusted to move to the main detection anode areaSince the kinetic energy of the ions in the repulsion region has a certain dispersion, few ions will hit the secondary detection anode region, as shown in fig. 1, the signal value on the second detection anode is detected, the peak integral values and the greatest common factor of the multiple groups of signals in the second detection anode region are calculated, and the obtained greatest common factor is the single ion peak integral value z in the second detection anode region 1 ；
S27, calculating the peak integral value z formed by single ions in the first detection anode area according to the difference multiple n between the magnification of the first detection anode area and the magnification of the second detection anode area 2 ＝z 1 /n；
S28, calculating an ion count value for the first detected anode region from the peak integrated value of the signal detected for the first detected anode region and the first detected anode region single-ion peak integrated value.
In the embodiment, the main detection anode region and the auxiliary detection anode region are calibrated, compared and recorded, so that the attenuation degree of the amplification factor of the common main anode detection region along with the use time can be calculated, and the residual life of the main detection region can be calculated.
The auxiliary detection anode of the present invention can be used as a substitute for the main detection anode after the main detection anode is partially damaged.
It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.
The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments.
The foregoing is illustrative of embodiments of the present disclosure and is not intended to limit one or more embodiments of the present disclosure. Various modifications and alterations to one or more embodiments described herein will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of one or more embodiments of the present specification should be included in the scope of claims of one or more embodiments of the present specification. One or more embodiments of this specification.
Claims (10)
1. A detection method of a reflection type time-of-flight mass spectrometer is characterized by comprising the following steps:
calculating V 2 A voltage value;
to pulse repulsion zone V 2 V calculated by application ratio 2 The voltage value is lower than the voltage in the preset range and is increased to be larger than the calculated V by the preset step length 2 Searching voltage to enable the signal detected by the first detection anode to be highest, recording the signal detected by the first detection anode as a first signal when ions exceeding a first quantity threshold value impact on the first detection anode, and calculating the peak integral value of a plurality of groups of analog signal values in the first signal;
increase V 2 Searching voltage to enable the signal detected by the second detection anode to be the highest, obtaining the signal detected by the first detection anode through multiple pulse repulsion when ions lower than a second number threshold value are impacted on the first detection anode, recording the signal as a second signal, and calculating the peak integral value of a plurality of groups of analog signal values in the second signal;
carrying out maximum common factor calculation on peak integral values of a plurality of groups of analog signal values in the second signal, wherein the obtained maximum common factor is a peak integral value formed by one ion;
and dividing the peak integral value of a plurality of groups of analog signal values in the first signal by the peak integral value formed by one ion to obtain the counting value of the ion.
2. The reflective time-of-flight mass spectrometer detection method of claim 1, further comprising:
increase V 2 A voltage value, calculating a peak integral value of a signal detected by the first detection anode in real time, wherein the peak integral value is in a direct proportion relation with the number of ions striking the detection anode;
calculating the ratio of the number of ions falling to the first detection anode region to the total number of ions a%, the ratio of the number of ions falling to the second detection anode region to the total number of ions a%/(1-a%), and the peak integrated value x of the signal detected by the first detection anode region to the peak integrated value y of the signal detected by the second detection anode region at that time, from the decay multiple of the peak integrated value of the first detection anode region;
judging whether x/y is equal to a%/(1-a%), if not, then the magnification of the second detection anode area is the magnification of the first detection anode area
Doubling;
decrease V 2 Voltage value, detecting signal value on the second detection anode, calculating peak integral value and maximum common factor of multiple groups of signals in the second detection anode area, wherein the obtained maximum common factor is single ion peak integral value z in the second detection anode area 1 ；
Calculating the peak integral value z formed by single ions in the first detection anode area according to the difference multiple n between the magnification of the first detection anode area and the magnification of the second detection anode area 2 ＝z 1 /n；
The ion count value of the first detection anode region is calculated from the peak integrated value of the signal detected by the first detection anode region and the single-ion peak integrated value of the first detection anode region.
3. A reflective fly as claimed in claim 1 or 2The detection method of the line time mass spectrometer is characterized by comprising the following steps: calculating V from the reflection time-of-flight formula 2 A voltage value, the reflective time-of-flight formula being:
wherein E is 1 、E 2 、E 3 、E 4 The electric field intensity of the pulse repulsion zone, the acceleration zone, the first reflection zone and the second reflection zone respectively,/ 1 、l 2 、l 3 、l 4 L is the length of the ion from the exit of the pulse repulsion area, the length of the acceleration area, the length of the first reflection area, the length of the second reflection area and the length of the field-free flight area, and d is the distance between the center of the repulsion area and the center of the first detection anode.
4. A reflective time-of-flight mass spectrometer detection method according to claim 1 or 2, characterized in that: the preset range is 20V-30V; the preset stepping length is 1V; the peak integral value is the integral of the ion current intensity on the time axis.
5. A reflective time-of-flight mass spectrometer detection device, comprising: the ion detection area comprises a first microchannel plate, a second microchannel plate, a first detection anode and a second detection anode, the first microchannel plate and the second microchannel plate are installed along a first direction, the first detection anode and the second detection anode are installed along a second direction, the first detection anode and the second detection anode are connected with the second microchannel plate and the detection anode switching circuit, the preamplification circuit is connected with the detection anode switching circuit and the ADC data acquisition system, the ADC data acquisition system is connected with the upper computer, the detection anode switching circuit is used for switching the first detection anode and the second detection anode, and the preamplification circuit is used for switching the first detection anode and the second detection anode, The current signal output by the second detection anode is converted into a voltage signal and amplified, the ADC data acquisition system is used for data acquisition and data transmission, and the upper computer is used for processing and calculating the acquired data.
6. A reflective time-of-flight mass spectrometer detection apparatus according to claim 5, wherein: the detection anode switching circuit comprises a first coupling capacitor, a second coupling capacitor and a switch, the first coupling capacitor is connected with the first detection anode, the second coupling capacitor is connected with the second detection anode, and the switch is connected with the first coupling capacitor, the second coupling capacitor and the pre-amplification circuit.
7. A reflective time-of-flight mass spectrometer detection apparatus according to claim 6, wherein: the preamplification circuit comprises a current-voltage conversion circuit and a voltage amplification circuit, the current-voltage conversion circuit is connected with the voltage amplification circuit and the change-over switch, the current-voltage conversion circuit is used for converting current signals output by the first detection anode and the second detection anode into voltage signals, and the voltage amplification circuit is used for amplifying the voltage signals converted by the current-voltage conversion circuit.
8. A reflective time-of-flight mass spectrometer detection apparatus according to claim 5, wherein: the ADC data acquisition system comprises an ADC acquisition chip, an FPGA chip and a memory, wherein the ADC acquisition chip is connected with the FPGA chip through the memory, the ADC acquisition chip is connected with the pre-amplification circuit, the ADC acquisition chip is used for converting an analog voltage signal into a digital signal, the FPGA chip is used for controlling data acquisition and data transmission, and the memory is used for temporarily storing acquired data.
9. A reflective time-of-flight mass spectrometer detection apparatus according to claim 5, wherein: the first microchannel plate and the second microchannel plate are arranged along a Y axis, the first detection anode and the second detection anode are arranged along an X axis, the X axis is parallel to a polar plate in the reflection type time-of-flight mass spectrometer, and the Y axis is perpendicular to the polar plate in the reflection type time-of-flight mass spectrometer.
10. A reflective time-of-flight mass spectrometer detection apparatus according to claim 5, wherein: and an inlet polar plate of the ion detection area is of a grid structure with the transmittance of more than 90%.
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