Test Method and Equipment for Dynamically Deformed Beam Spots of LA-ICP-MS

Abstract

The present invention relates to a method and device for testing a dynamically deformed beam spot of LA-ICP-MS. The method includes obtaining the phase boundary shape on the surface of a sample and the three-dimensional phase distribution inside the sample; determining a target particle and a standard sample according to the three-dimensional phase distribution of the sample, and controlling the laser spot of the standard sample to obtain the beam spot of the target particle; obtaining each ablation layer according to the three-dimensional phase distribution, and determining the change sequence of the cross-sectional shape of the target particle corresponding to the beam deformation sheet for the sample according to the shape of the cross-section of the target particle ablation layer corresponding to the three-dimensional phase distribution; the shape of the bright area of the beam deformation sheet is a geometrically similar figure corresponding to the cross-sectional shape of the beam spot to be ablated; running the beam deformation sheet frame by frame in the order of the change sequence of the cross-sectional shape of the target particle, so that the beam ablates the sample. The present invention can improve the accuracy of sample composition data and save samples.

Description

Technical Field

[0001] The present invention relates to the technical field of geological sample testing by dynamic deformation laser beam spot ablation, and particularly to a testing method and device for a dynamic deformation beam spot of LA-ICP-MS. Background Art

[0002] Current laser ablation-inductively coupled plasma mass spectrometry (hereinafter collectively referred to as LA-ICP-MS) methods and devices can be applied to the testing of solid components in the fields of geology, materials science, criminal investigation, archaeology, environmental science, etc. Among them, geological samples have the characteristics of complex and variable micro-region morphologies. Due to the characteristics of the well-known LA-ICP-MS methods and devices, only the beam spot cross-sectional shape can be determined in advance through a diaphragm with a fixed shape, and the beam spot cross-section during the laser ablation process does not deform, and all components within the beam spot area will be ablated, bringing problems such as difficulty in real-time change, difficulty in selecting the beam spot shape, and introduction of impurities at the ablation point.

[0003] Although a method for continuously adjusting the spatial morphology of a focused fiber laser beam is disclosed in the prior art, it is necessary to calculate the defocus amount value corresponding to the required beam spatial morphology for actual processing, and then continuously adjust the vertical distance of the adjustable cladding head in the longitudinal direction to achieve the purpose of continuously changing the defocus amount of the processing surface, so as to realize the continuous adjustment of the laser beam spatial morphology. Because the pulsed laser of the well-known LA-ICP-MS changes the sample surface morphology and defocus amount every time it ablates, and when the sample is a geological sample, only adjusting the vertical distance of the cladding head to change the defocus amount will still ablate non-target particles within the beam spot, and these calculation and adjustment steps are time-consuming for the adjustment of the laser beam.

[0004] The prior art also discloses that the filtering small hole of the laser beam spatial shaping device is located at the focus (maximum energy density) of the confocal system. Only when the energy range of the beam cannot ablate the filtering small hole can the beam shaping be realized, and the deformation of the laser beam spot within the ablation energy range of LA-ICP-MS cannot be realized, which does not meet the testing technical requirements of LA-ICP-MS. Summary of the Invention

[0005] In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide a testing method and device for a dynamic deformation beam spot of LA-ICP-MS.

[0006] To achieve the above purpose, the present invention provides the following solutions:

[0007] A testing method for a dynamic deformation beam spot of LA-ICP-MS includes:

[0008] Obtaining the shape of the phase boundary on the sample surface and the three-dimensional phase distribution inside the sample;

[0009] Determine the target particles and the standard sample according to the three-dimensional phase distribution of the sample, and perform laser spot control on the standard sample to obtain the beam spot of the target particles;

[0010] Obtain each ablation layer according to the three-dimensional phase distribution, and determine the target particle cross-section shape change sequence of the beam deformation sheet corresponding to the sample according to the shape of the cross-section of the target particle ablation layer corresponding to the three-dimensional phase distribution; the shape of the bright area of the beam deformation sheet corresponds to the geometrically similar figure of the cross-section shape of the beam spot to be ablated;

[0011] Run the beam deformation sheet frame by frame according to the order of the target particle cross-section shape change sequence to ablate the sample with the beam; after the beam ablates the sample once, replace the beam deformation sheet with the next one corresponding to a deeper position of the sample, so as to change the shape of the beam spot in turn to implement LA-ICP-MS testing.

[0012] Preferably, when the beam deformation sheet runs frame by frame, the beam passes through the beam deformation sheet as parallel light outside the double focal length of the lens.

[0013] Preferably, when there is a position where the vertical cross-section shape of the three-dimensional phase distribution of the target particle remains unchanged, the beam passes through the beam deformation sheet without changing the shape of the beam spot for at least two ablations.

[0014] Preferably, the obtaining of each ablation layer according to the three-dimensional phase distribution includes:

[0015] Obtain the volume and depth of the internal phase distribution according to the three-dimensional phase distribution;

[0016] Obtain the ablation layer according to the ablation rate of each phase, the volume and the depth; the ablation rate is obtained when the standard sample performs laser spot control.

[0017] Preferably, the position of the beam spot is constrained by the surface phase boundary shape.

[0018] Preferably, the beam passes through the beam deformation sheet in a parallel or confocal manner; the beam is allowed to pass through when the beam deformation sheet pauses; the pause period of the beam deformation sheet is not less than the single pulse period of the beam.

[0019] A testing device for the LA-ICP-MS dynamic deformation beam spot, which is used for the above-mentioned LA-ICP-MS dynamic deformation beam spot testing method. The testing device includes a mass spectrometer module, a beam deformation sheet, a lens module, a sample chamber, a laser module, a carrier gas module and a vacuum module;

[0020] The beam deforming sheet is generated from the three-dimensional phase layered structure of the sample; the pipelines of the sample chamber are respectively connected to the mass spectrometer module, the carrier gas module and the vacuum module; the sample chamber is used for placing the sample; the laser module is used for emitting a beam; when the sample chamber is evacuated by the vacuum module and the sample is detachably or fixedly arranged, the beam forms a beam spot through the lens module and the beam deforming sheet to erode the sample, and the eroded product is sent into the mass spectrometer module by the carrier gas of the carrier gas module to test the composition of the sample;

[0021] The beam deforming sheet is a film, a sheet-shaped excitation source arranged in a strip, a liquid crystal polarizer with more than one extinction position shape or a digitally controlled deforming excitation source.

[0022] Preferably, when the beam deforming sheet is the film or the sheet-shaped excitation source arranged in a strip, the testing device further includes a first stepping motor, a second stepping motor, a first runner connected to the first stepping motor and a second runner connected to the second stepping motor;

[0023] The first stepping motor is used for driving the first runner so that the first runner winds and fixes the beam deforming sheet that does not transmit the beam;

[0024] The second stepping motor is used for driving the second runner so that the second runner winds and fixes the beam deforming sheet that has transmitted the beam.

[0025] Preferably, when the beam deforming sheet is the liquid crystal polarizer or the digitally controlled deforming excitation source, the beam deforming sheet is attached and fixed at the position where the laser module emits the beam.

[0026] Preferably, at least one horizontal coplanar plane is included in the mass spectrometer module, the sample chamber, the laser module, the beam, the beam spot, the sample, the carrier gas module and the vacuum module, and the beam spot has a polished plane on the surface of the sample that does not include a surface coating to perform erosion.

[0027] According to the specific embodiments provided by the present invention, the following technical effects are disclosed by the present invention:

[0028] The present invention provides a method and device for testing a dynamically deformed beam spot of LA-ICP-MS. The method includes obtaining the phase boundary shape on the surface of a sample and the three-dimensional phase distribution inside the sample; determining target particles and a standard sample according to the three-dimensional phase distribution of the sample, and controlling the laser spot of the standard sample to obtain the beam spot of the target particles; obtaining each erosion layer according to the three-dimensional phase distribution, and determining the change sequence of the cross-sectional shape of the target particle corresponding to the beam deformation sheet for the sample according to the shape of the cross-section of the target particle erosion layer corresponding to the three-dimensional phase distribution; the bright area shape of the beam deformation sheet corresponds to a geometrically similar figure of the cross-sectional shape of the beam spot to be eroded; running the beam deformation sheet frame by frame in the order of the change sequence of the cross-sectional shape of the target particle, so that the beam erodes the sample; after the beam erodes the sample once, replacing the beam deformation sheet with the next one corresponding to a deeper position of the sample, thereby sequentially changing the shape of the beam spot to implement LA-ICP-MS testing. The present invention performs dynamic deformed erosion sampling on the erosion area, and uses a parallel light or laser beam spot with a real-time deformed cross-sectional shape to replace the laser beam spot that does not deform or only changes the defocus amount during the erosion process, which not only realizes dynamic sampling of an irregularly shaped erosion area, but also can purposefully select specific components, reduces the mixing of impurities in single-point sampling, improves the accuracy of sample composition data, and saves samples. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0030] Figure 1 It is a flowchart of the method in Embodiment 1 provided by the present invention;

[0031] Figure 2 It is a schematic structural diagram of Embodiment 2 provided by the present invention;

[0032] Figure 3 It is a schematic structural diagram of Embodiment 3 provided by the present invention;

[0033] Figure 4 It is a schematic structural diagram of Embodiment 4 provided by the present invention;

[0034] Figure 5 It is a schematic diagram of the beam deformation sheet for testing geological samples in Embodiment 5 provided by the present invention;

[0035] Figure 6 It is a schematic diagram of the beam deformation sheet for testing geological samples in Embodiment 6 provided by the present invention;

[0036] Figure 7 Schematic diagram of the beam deformation sheet for testing geological samples in Embodiment 7 provided by the present invention;

[0037] Figure 8 Schematic diagram of the beam deformation sheet for testing geological samples in Embodiment 8 provided by the present invention.

[0038] Symbol description:

[0039] 1 - Mass spectrometer module, 11 - First stepping motor, 101 - First runner, 12 - Second stepping motor, 102 - Second runner, 2 - Beam deformation sheet, 21 - Single mineral deformation sheet, 22 - Zoned deformation sheet, 23 - Scattered mineral deformation sheet, 24 - Anhedral grain deformation sheet, 3 - Lens module, 31 - Prism module, 4 - Sample chamber, 5 - Laser module, 6 - Beam, 61 - Beam spot, 7 - Sample, 8 - Carrier gas module, 9 - Vacuum module. Detailed implementation manners

[0040] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0041] Referring to "embodiment" in this article means that the specific features, structures or characteristics described in conjunction with the embodiment can be included in at least one embodiment of the present application. The phrase appears in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0042] The terms "first", "second", "third" and "fourth" etc. in the specification and claims of the present application and the accompanying drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a series of steps, processes, methods, etc. included do not limit to the listed steps, but optionally further include steps not listed, or optionally further include other step elements inherent to these processes, methods, products or devices.

[0043] The object of the present invention is to provide a method and device for testing the dynamically deformed spot of LA-ICP-MS, which realizes the dynamically deformed erosion sampling of the erosion area. By using a parallel light or laser spot with a cross-sectional shape that deforms in real time to replace the laser spot that does not deform or only changes the defocus amount during the erosion process, it can not only realize the dynamic sampling of an irregularly shaped erosion area, but also purposefully select specific components, reduce the mixing of impurities in single-point sampling, improve the accuracy of sample component data, and save samples.

[0044] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] Example 1:

[0046] Figure 1 It is a flowchart of the method in Example 1 provided by the present invention. As Figure 1 shown, the present invention provides a method for testing the dynamically deformed spot of LA-ICP-MS, including:

[0047] Step 100: Obtain the phase boundary shape on the surface of the sample and the three-dimensional phase distribution inside the sample;

[0048] Step 200: Determine the target particles and the standard sample according to the three-dimensional phase distribution of the sample, and perform laser spot control on the standard sample to obtain the spot of the target particles;

[0049] Step 300: Obtain each erosion layer according to the three-dimensional phase distribution, and determine the sequence of changes in the cross-sectional shape of the target particle of the sample corresponding to the beam deformation sheet according to the shape of the cross-section of the target particle erosion layer corresponding to the three-dimensional phase distribution; the bright area shape of the beam deformation sheet corresponds to a geometrically similar figure of the cross-sectional shape of the spot to be eroded;

[0050] Step 400: Run the beam deformation sheet frame by frame in the order of the sequence of changes in the cross-sectional shape of the target particle to erode the sample with the beam; after the beam erodes the sample once, replace the beam deformation sheet with the next one corresponding to a deeper position of the sample, so as to change the shape of the spot in turn to implement the LA-ICP-MS test.

[0051] Specifically, Step 100 for obtaining the phase boundary shape on the surface of the sample and the three-dimensional phase distribution inside the sample can be realized by means such as CT scanning, or X-ray transmission imaging, or three-dimensional confocal Raman spectroscopy, or CL image to obtain mineral zoning.

[0052] Further, in step 200, the phase types are first determined according to the phase distribution in step 100, and at least one type of target particle to be ablated is determined from the phase types. A mineral with uniform composition and at least one elemental component the same as that of the target particle or the same mineral phase as the target particle is selected as the standard sample. A laser beam spot with a certain power, wavelength, and radius is used to pre-ablated the standard sample, the ablation rate of each phase is measured, and the beam spot with suitable power, wavelength, and radius for the specific sample is adjusted. The purpose of step 200 is to select the mineral to be measured and the standard sample.

[0053] Optionally, the steps of step 300 are as follows:

[0054] According to the volume and depth of the phase distribution inside the sample, each ablation stratification is obtained by classifying and dividing by the ablation rate of each phase. According to the shape of the ablation stratification cross-section of the target particle corresponding to the three-dimensional phase distribution inside the sample, a beam deformation sheet is generated to correspond to the shape change of the target particle cross-section of the sample and arranged from shallow to deep. The shape of the bright area of the beam deformation sheet corresponds to the geometrically similar figure of the beam spot cross-section to be ablated, and the position of the beam spot is constrained by the shape of the surface phase boundary.

[0055] Specifically, the beam deformation sheet runs frame by frame in the order arranged in step 300. When running, the beam is outside the double focal length on the side of the lens module facing away from the sample chamber, and the parallel or confocal beam passes through the beam deformation sheet; when the beam deformation sheet pauses, the beam is allowed to pass through, and the pause period ≥ the single pulse period of the beam; after the beam ablates the sample once, the beam deformation sheet is changed to the next one corresponding to a deeper position of the sample, so as to change the shape of the beam spot in turn and implement LA-ICP-MS testing.

[0056] Preferably, when there are more than one positions where the vertical cross-section shape of the three-dimensional distribution of the target particle remains unchanged, the beam passing through the beam deformation sheet does not change the shape of the beam spot for at least two ablations.

[0057] Example 2:

[0058] Figure 2 This is the structural schematic diagram in Example 2 provided by the present invention, as Figure 2As shown in the figure, a LA-ICP-MS device with a dynamically deformed beam spot includes: a mass spectrometer module 1, a beam deformation sheet 2, a lens module 3, a sample chamber 4, a laser module 5, a carrier gas module 8, and a vacuum module 9; the beam deformation sheet 2 is more than one film generated according to the three-dimensional phase stratification structure of the sample 7; the sample chamber 4 is connected to the mass spectrometer module 1, the carrier gas module 8, and the vacuum module 9 through pipelines; the laser module 5 emits a beam 6; when the sample chamber 4 is evacuated by the vacuum module 9 and the sample 7 is detachably fixed, the beam 6 forms a beam spot 61 through at least the lens module 3 and the beam deformation sheet 2 to ablate the sample 7. When the beam 6 is a parallel beam or a beam in a non-ablative energy range, a prism module 31 can also be added. The prism module 31 deflects the beam 6 incident on the beam deformation sheet 2 or the lens module 3, and the ablation products are sent into the mass spectrometer module 1 by the carrier gas of the carrier gas module 8 to test the composition of the sample 7; when the beam deformation sheet 2 is a film or a sheet-shaped excitation source arranged in a strip, the first stepping motor 11 drives the first runner 101, and the first runner 101 winds and fixes the beam deformation sheet 2 that has not transmitted the beam 6; the second stepping motor 12 drives the second runner 102 to wind and fix the beam deformation sheet 2 that has transmitted the beam 6.

[0059] Embodiment 3:

[0060] Figure 3 It is a schematic structural diagram in Embodiment 3 provided by the present invention, as Figure 3 shown. Compared with the above, the beam deformation sheet 2 in Embodiment 3 is a sheet-shaped excitation source arranged in a strip, which directly changes the shape of the excitation source, thereby changing the shape of the light source. According to the known technology, the change in the shape of the light source at a distance greater than twice the focal length of the convex lens in the lens module can constrain the shape of the beam spot 61. At this time, the beam deformation sheet 2 passes through the laser module 5 unidirectionally. When the beam deformation sheet 2 passes through, it adheres to but does not fix the position of the beam 6 emitted by the laser module 5 to change the shape of the beam 6. The first stepping motor 11 drives the first runner 101, and the first runner 101 winds and fixes the beam deformation sheet 2 that has not passed through the laser module 5; the second stepping motor 12 drives the second runner 102 to wind and fix the beam deformation sheet 2 that has passed through the laser module 5.

[0061] Embodiment 4:

[0062] Figure 4 It is a schematic structural diagram in Embodiment 4 provided by the present invention, as Figure 4 shown. Compared with Embodiment 2 and Embodiment 3, the beam deformation sheet 2 is one of a liquid crystal polarizer or a digitally controlled deformation excitation source, then the beam deformation sheet 2 adheres to and fixes the position of the beam 6 emitted by the laser module 5. At this time, the shape of the layered beam spot 61 of the beam deformation sheet 2 is controlled and stored by a computer.

[0063] Embodiment 5:

[0064] Figure 5Schematic diagram of the beam deformation sheet for testing geological samples in Example 5 provided by the present invention, as shown in Figure 5 As shown, based on the above-mentioned device, when analyzing single mineral grains with changing vertical cross-sectional shapes in sample 7, such as unzoned garnet or pyrite with a decreasing cross-sectional radius from the surface of sample 7 towards the depth, it is necessary to avoid the beam spot 61 from eroding other minerals during the deep erosion process. At this time, the beam deformation sheet 2 is subdivided into single mineral deformation sheets 21, and the bright area shapes of the single mineral deformation sheets 21 are continuous and the transmittance is uniform.

[0065] Example 6:

[0066] Figure 6 Schematic diagram of the beam deformation sheet for testing geological samples in Example 6 provided by the present invention, as shown in Figure 6 As shown, based on Example 2, Example 3, and Example 4, when analyzing mineral zonings with changing vertical cross-sectional shapes in sample 7, such as zoned zircon, apatite, monazite, garnet, pyroxene, and feldspar, it is necessary for the beam spot 61 to erode coeval minerals during the deep erosion process. At this time, the beam deformation sheet 2 is subdivided into zoned deformation sheets 22. The bright area shape of the zoned deformation sheet 22 forms a similar figure with the corresponding mineral zoning, and the transmittance of the wide zone is higher than that of the narrow zone. When focusing during erosion, the beam spot 61 coincides and focuses on the zoning of the target particle. When there are multiple zonings, the mineral zonings are analyzed from the inside out in the mineral cross-section, and the method for judging the inner and outer zonings belongs to well-known technology; when a single zoning runs through the entire crystal and the average width is less than 1 μm, sampling of a single zoning can be abandoned. According to common knowledge, zonings are caused by different crystallization periods of the same mineral. In chronological studies, coeval mineral zonings should be selected as much as possible. Therefore, accurately selecting zonings in this example is beneficial to improving the accuracy of chronological data.

[0067] Example 7:

[0068] Figure 7 Schematic diagram of the beam deformation sheet for testing geological samples in Example 7 provided by the present invention, as shown in Figure 7 As shown, based on Example 2, Example 3, and Example 4, when analyzing multiple fine-grained same minerals in sample 7, which is mainly used for the grade analysis of lean ores, dispersed minerals, and precious metal ores, such as the PGE analysis of sulfides in sparsely disseminated copper-nickel-platinum ores, the analysis of fine-grained rare earth minerals in alkaline rocks, the separation structure of sulfide solid solutions, and the trace element analysis of acicular rutile and ilmenite. At this time, the beam deformation sheet 2 is subdivided into scattered point mineral deformation sheets 23, and the bright area shapes of the scattered point mineral deformation sheets 23 are discontinuous dots, and the transmittance of the bright area decreases according to the size of the corresponding target particles. The method for changing the transmittance of the beam deformation sheet 2 belongs to well-known technology.

[0069] Example 8:

[0070] Figure 8Schematic diagram of the beam deformation sheet for testing geological samples in Example 8 provided by the present invention, as Figure 8 shown. Based on Example 2, Example 3, and Example 4, non-automorphic crystal phases such as glass and xenomorphic minerals in sample 7 are analyzed. At this time, the beam deformation sheet 2 is subdivided into non-automorphic particle deformation sheets 24. At this time, there is a high probability that the target particles exist at positions where the vertical cross-sectional shape of the three-dimensional distribution of the phases remains unchanged (such as volcanic glass beads). If so, the beam 6 passes through the beam deformation sheet 2 without changing the shape of the beam spot 61 for at least two erosions.

[0071] In addition, Examples 5, 6, 7, and 8 all follow the principle that the diameter of the beam spot 61 decreases during the erosion process from the surface of sample 7 to the deep part. If non-target particles cover the surface of the target particles, or the target particles form a conical annulus, the non-target particles can be eroded in advance. Separating the eroded non-target particles from the target particles is beneficial to improving the accuracy of LA-ICP-MS data.

[0072] Features not detailed in this application belong to common knowledge. For example, the mass spectrometer module 1 involves a mass spectrometer, the types of lasers in the laser module 5, the gas path system of the carrier gas module 8, the vacuum equipment of the vacuum module 9, the computer control system, and the method for generating the beam deformation sheet 2, the specific types and materials of the stepping motor, the runner, the lens module 3, and the prism module 31, and the composition calculation method of the sample 7.

[0073] The beneficial effects of the present invention are as follows:

[0074] (1) By obtaining the three-dimensional topography of the geological sample in advance, the real-time morphological change of the beam spot is realized, reducing the time-consuming of measurement and adjustment in the prior art.

[0075] (2) Dynamic sampling of the erosion area of irregular shapes (such as microscopic mineral inclusions, solid solution separation structures, and fine annuli in geological samples) can be realized. Tiny, discontinuous, or irregularly shaped particles (such as acicular ilmenite, rutile, and irregular vitric clasts in lunar rocks) that are difficult to test by traditional LA-ICP-MS can be tested, broadening the broad-spectrum of the testable range of geological samples.

[0076] (3) Specific mineral components can be purposefully selected, reducing the mixing of impurities in single-point sampling and improving the accuracy of sample composition data (such as single-mineral isotope ratios, single-mineral trace element contents, and dating of zircon, apatite, and monazite).

[0077] (4) When calculating the ore grade by large-scale scanning erosion, simultaneous sampling of multiple same-kind mineral particles can also be realized, saving sampling time.

[0078] In the embodiments described in this specification, a progressive approach is adopted. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For the relevant parts, reference can be made to the description in the method section.

[0079] In this article, specific examples are used to elaborate on the principles and implementation manners of the present invention. The descriptions of the above embodiments are only used to help understand the method of the present invention and its core idea. At the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A test method for a dynamically deformed beam spot of LA-ICP-MS, characterized in that, Comprising: Obtaining the phase boundary shape of the surface of the sample and the three-dimensional phase distribution inside the sample; Determining the target particles and the standard sample according to the three-dimensional phase distribution of the sample, and performing laser spot control on the standard sample to obtain the beam spot of the target particles; Obtaining each ablation layer according to the three-dimensional phase distribution, and determining the target particle cross-section shape change sequence of the beam deformation sheet corresponding to the sample according to the shape of the target particle ablation layer cross-section corresponding to the three-dimensional phase distribution; the bright area shape of the beam deformation sheet corresponds to a geometrically similar figure of the cross-section shape of the beam spot to be ablated; Running the beam deformation sheet frame by frame in the order of the target particle cross-section shape change sequence to ablate the sample with the beam; after the beam ablates the sample once, replace the beam deformation sheet with the next one corresponding to a deeper position of the sample, so as to change the shape of the beam spot in turn to implement LA-ICP-MS testing.

2. The test method for the dynamically deformed beam spot of LA-ICP-MS according to claim 1, wherein, When the beam deformation sheet runs frame by frame, the beam passes through the beam deformation sheet as parallel light outside the double focal length of the lens.

3. The test method for the LA-ICP-MS dynamic deformed beam spot according to claim 1, wherein When there is a position where the vertical cross-section shape of the three-dimensional phase distribution of the target particle remains unchanged, the beam passes through the beam deformation sheet without changing the beam spot shape for at least two ablations.

4. The test method for the dynamically deformed beam spot of LA-ICP-MS according to claim 1, wherein The obtaining each ablation layer according to the three-dimensional phase distribution includes: Obtaining the volume and depth of the internal phase distribution according to the three-dimensional phase distribution; Obtaining the ablation layer according to the ablation rate of each phase, the volume and the depth; the ablation rate is obtained when the standard sample performs laser spot control.

5. The test method for the dynamically deformed spot of LA-ICP-MS according to claim 1, characterized in that, The position of the beam spot is constrained by the surface phase boundary shape.

6. The test method for the dynamically deformed beam spot of LA-ICP-MS according to claim 1, wherein The beam passes through the beam deformation sheet in a parallel or confocal manner; the beam is allowed to pass through when the beam deformation sheet pauses; the pause period of the beam deformation sheet is not less than the single pulse period of the beam.

7. A test device for a dynamically deformed beam spot of LA-ICP-MS, characterized in that, A test method for implementing the LA-ICP-MS dynamic deformed beam spot as described in any one of claims 1 to 6, the test device includes a mass spectrometer module, a beam deformation sheet, a lens module, a sample chamber, a laser module, a carrier gas module and a vacuum module; The beam deformation sheet is generated by the three-dimensional phase stratification structure of the sample; the pipelines of the sample chamber are respectively connected to the mass spectrometer module, the carrier gas module and the vacuum module; the sample chamber is used to place the sample; the laser module is used to emit a beam; when the sample chamber is evacuated by the vacuum module and the sample is detachably fixed, the beam forms a beam spot through the lens module and the beam deformation sheet to ablate the sample, and the ablated products are sent into the mass spectrometer module by the carrier gas of the carrier gas module to test the composition of the sample; The beam deformation sheet is a film, a sheet excitation source arranged in a strip, a liquid crystal polarizer with more than one extinction shape or a digital control type deformed excitation source.

8. The test device for the LA-ICP-MS dynamic deformed beam spot according to claim 7, characterized in that When the beam deformation sheet is the film or the sheet excitation source arranged in a strip, the test device further includes a first stepping motor, a second stepping motor, a first runner connected to the first stepping motor and a second runner connected to the second stepping motor; The first stepping motor is used to drive the first runner so that the first runner winds and fixes the beam deforming sheet that has not transmitted the beam. The second stepping motor is used to drive the second runner so that the second runner winds and fixes the beam deforming sheet that has transmitted the beam.

9. The test device for the dynamically deformed beam spot of LA-ICP-MS according to claim 7, characterized in that, When the beam deforming sheet is the liquid crystal polarizer or the digital control type deformation excitation source, the beam deforming sheet is attached and fixed at the position where the laser module emits the beam.

10. The test device for the LA-ICP-MS dynamic deformed beam spot according to claim 7, characterized in that, The mass spectrometer module, the sample chamber, the laser module, the beam, the beam spot, the sample, the carrier gas module and the vacuum module at least include a coplanar plane in the horizontal direction, and the beam spot has a polished plane without a surface coating on the surface of the sample to perform ablation.

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