CN109211847B - Method for analyzing chemical components of single suspended particles by adopting analysis device - Google Patents
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- 229910052594 sapphire Inorganic materials 0.000 claims description 3
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- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/65—Raman scattering
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Abstract
The invention discloses a device for analyzing chemical components of single suspended particles, which comprises a pulse laser, a hollow beam particle capturing system, an atomic emission spectrum acquisition system, a Raman spectrum acquisition system and an imaging system, wherein the hollow beam particle capturing system is used for capturing particles; the hollow beam particle capturing system comprises a continuous laser, a hollow beam generating device, a beam expanding and collimating device, a high-reflection mirror, a first convergent lens and a sample cell, wherein sample particles are arranged in the sample cell; the atomic emission spectrum acquisition system comprises a first coupling lens and a laser-induced breakdown spectrometer; the Raman spectrum acquisition system comprises a second coupling lens and a Raman spectrometer. In addition, the invention also provides a method for analyzing the chemical composition of the single suspended particles by using the device. The invention captures sample particles by using hollow beams, ionizes the sample particles by using a pulse laser, and acquires atomic emission spectrum information and Raman spectrum information of the sample particles to realize in-situ analysis of element composition and material composition of single suspended particles.
Description
Technical Field
The invention belongs to the field of nonlinear optical application, and particularly relates to a method for analyzing chemical components of single suspended particles by using an analysis device.
Background
At present, the detection method for the particulate matters in the air comprises the following steps: infrared absorption spectroscopy, ultraviolet fluorescence, chemiluminescence, turbidity, scattering, and the like, however, these methods cannot detect the composition and structure of fine particulate matter (aerosol, carbon black, trace heavy metals, and the like) in the air. The laser-induced breakdown spectroscopy technology is used as a novel in-situ measurement technology, can analyze solid samples and liquid and gaseous samples, has the advantages of rapidness, real-time performance, telemetability, no need of pretreatment, and realization of multi-element simultaneous analysis, and is successfully applied to various fields such as materials, metallurgy, combustion, environment, archaeology, space exploration, medicine, military and the like.
Laser-Induced Breakdown Spectroscopy (LIBS) utilizes plasma generated by pulsed Laser to ablate and excite substances in a sample, and obtains a spectrum emitted by atoms excited by the plasma through the spectrometer so as to identify the element composition in the sample, thereby identifying, classifying, qualitatively and quantitatively analyzing the material. The Laser-induced breakdown raman spectroscopy (librs) technology is an in-situ measurement spectroscopy technology for simultaneously obtaining an atomic spectrum and a molecular spectrum of a substance at the same site through LIBS and raman spectroscopy, and can simultaneously complete micro-area in-situ measurement of the atomic spectrum and the molecular spectrum by analyzing and processing data of the LIBS and the raman spectroscopy, so that rapid quantitative analysis and identification can be carried out on elements and molecular compositions of a sample. However, with the currently known reports, LIBS is limited to online in situ detection of sample particles attached to some solid, detection of particles suspended in a fluid such as air or liquid is still impossible, and since LIBS systems can break down objects, the solid to which the sample particles are attached inevitably causes noise to the spectrometer, thereby affecting accurate analysis of the particle composition.
In the optical field, a hollow beam refers to a beam whose lateral amplitude distribution satisfies a high-order bessel function, and whose lateral light intensity distribution appears as a series of concentric circles whose centers are dark. According to the principle of optophoretic force, a hollow light beam can capture light-absorbing particles in a dark area, and the capture of light-absorbing particles in air by using the hollow light beam is the most stable device known at present, and the three-dimensional operation of the particles can be realized by adjusting the size or power of the hollow light beam. The unique light intensity distribution of the hollow light beam enables the hollow light beam to have important application value in the fields of particle manipulation, nonlinear optics and the like.
At present, no real-time in-situ analysis method for realizing the composition of particles in the air is reported, and the main reasons are as follows: the currently known detection methods cannot analyze the chemical composition of particulate matter in a fluid (such as air, etc.); laser capture technology based on optophoretic force has not been organically combined with spectroscopic analysis systems.
Disclosure of Invention
The present invention provides a method for analyzing chemical components of single suspended particles by using an analysis device, which includes converting a gaussian beam generated by a continuous laser into a hollow beam by using a hollow beam generation device, capturing sample particles in a sample cell, and ionizing the captured sample particles by using a pulse laser, thereby implementing in-situ analysis of elemental composition and material components of single fine particles suspended in air.
In order to solve the technical problems, the invention adopts the technical scheme that: an apparatus for chemical composition analysis of individual suspended particles, comprising a pulsed laser, characterized in that: the system also comprises a hollow beam particle capturing system, an atomic emission spectrum acquisition system, a Raman spectrum acquisition system and an imaging system;
the hollow beam particle capturing system comprises a continuous laser, a hollow beam generating device, a beam expanding and collimating device, a high reflecting mirror capable of changing the direction of a hollow beam, a first converging lens and a sample cell; the continuous laser, the hollow light beam generating device, the beam expanding and collimating device, the high-reflecting mirror and the first converging lens are sequentially arranged on the same light path, and sample particles are arranged in the sample pool;
the atomic emission spectrum acquisition system comprises a first coupling lens and a laser-induced breakdown spectrometer connected with the first coupling lens, wherein a first optical fiber used for connecting the first coupling lens and the laser-induced breakdown spectrometer is arranged between the first coupling lens and the laser-induced breakdown spectrometer;
the Raman spectrum acquisition system comprises a second coupling lens and a Raman spectrometer connected with the second coupling lens, and a second optical fiber used for connecting the second coupling lens and the Raman spectrometer is arranged between the second coupling lens and the Raman spectrometer;
the pulse light generated by the pulse laser is vertical to the hollow light beam reflected by the high reflector;
the imaging system includes an imaging device and a microscope objective disposed between the imaging device and the sample cell.
The above apparatus for chemical composition analysis of individual suspended particles is characterized in that: the continuous laser is a 532nm semiconductor continuous laser or an all-solid-state tunable titanium sapphire dye continuous laser.
The above apparatus for chemical composition analysis of individual suspended particles is characterized in that: the hollow beam generating device comprises a self-phase spatial beam modulation system, a cross-phase spatial beam modulation system, a biconic lens, a spatial light modulator or a phase plate which can generate a hollow beam.
The above apparatus for chemical composition analysis of individual suspended particles is characterized in that: the self-phase space light beam modulation system comprises a first convex lens and a nonlinear absorption medium which are sequentially arranged on the same light path.
The above apparatus for chemical composition analysis of individual suspended particles is characterized in that: the beam expanding and collimating device comprises a second converging lens and a third converging lens which are positioned on the same optical path, and the second converging lens is positioned between the hollow light beam generating device and the third converging lens.
The above apparatus for chemical composition analysis of individual suspended particles is characterized in that: the imaging device comprises a CCD camera, an ICCD camera or a CMOS camera.
The above apparatus for chemical composition analysis of individual suspended particles is characterized in that: the first converging lens is positioned between the high reflection mirror and the sample cell.
The above apparatus for chemical composition analysis of individual suspended particles is characterized in that: the imaging device, the laser-induced breakdown spectrometer and the Raman spectrometer are respectively positioned on different side parts of the sample cell.
In addition, the invention also provides a method for analyzing the chemical composition of single suspended particles by using the device, which is characterized by comprising the following steps:
step one, acquiring a continuous laser beam with Gaussian distribution from a continuous laser, and integrating the acquired continuous laser beam into a hollow beam through a hollow beam generating device;
step two, the hollow light beam obtained in the step one is incident to a high reflector after passing through a beam expanding collimation device, the high reflector is adjusted, the reflected hollow light beam is incident to a first convergent lens to form a convergent hollow light beam, and the convergent hollow light beam is incident to a sample cell;
step three, obtaining a beam of converged pulse light from a pulse laser, enabling the convergence center of the pulse light to coincide with the imaging center of an imaging device, and turning off the pulse laser;
spraying sample particles into the sample cell, capturing the sample particles at the position of the light trap by the converged hollow light beam incident into the sample cell, and adjusting the light intensity and the size of the hollow light beam to enable the position of the light trap to coincide with the imaging center of the imaging device;
step five, collecting scattered light generated by sample particles by a second coupling lens, and displaying Raman spectrum information by a Raman spectrometer;
opening a pulse laser to enable the converged pulse light to ionize the captured sample particles, and closing the pulse laser;
and seventhly, collecting the atomic emission spectrum generated by ionization of the sample particles by using the first coupling lens, and displaying the information of the atomic emission spectrum by using the laser-induced breakdown spectrometer.
Compared with the prior art, the invention has the following advantages:
1. the invention converts the Gaussian beam generated by the continuous laser into the hollow beam by arranging the hollow beam generating device, captures sample particles in the sample pool, and ionizes the captured sample particles by arranging the pulse laser, thereby realizing the online in-situ analysis of the element composition and the material composition of single fine particles suspended in air.
2. According to the invention, by arranging the spectrum acquisition system and the imaging device, the atomic emission spectrum information, the Raman spectrum information and the sample motion condition of the ionized sample can be obtained, the purpose of quantitative determination is realized, and a new thought is provided for the real-time online research of atmospheric pollution particles.
3. The analysis device has the advantages of simple structure, reasonable design, low cost and easy popularization.
4. The analysis method is easy to operate, can capture suspended particles with constantly changing positions, and carries out spectral analysis on the suspended particles, so that the on-line detection of single suspended matters is realized.
The technical solution of the present invention is further described in detail with reference to the accompanying drawings and embodiments.
Drawings
Fig. 1 is a schematic structural diagram of an apparatus for chemical composition analysis of individual suspended particles according to the present invention.
Fig. 2 is a schematic structural diagram of a pulse laser, a hollow beam particle capturing system, an atomic emission spectrum collecting system and an imaging system of the apparatus for chemical composition analysis of single suspended particles of the present invention.
FIG. 3 is a schematic structural diagram of the hollow beam generating device of the present invention.
FIG. 4 is a Raman spectrum of a single particle alumina measured in accordance with the present invention.
FIG. 5 is a standard Raman spectrum of alumina.
FIG. 6 is a graph of laser induced breakdown spectra of single particle alumina measured in accordance with the present invention.
FIG. 7 is a graph of standard laser induced breakdown spectroscopy for aluminum.
Description of reference numerals:
1-a continuous laser; 2-a hollow beam generating device; 2-1 — a first convex lens;
2-a non-linear absorbing medium; 3-a second converging lens; 4-a third converging lens;
5-high reflector; 6-a first converging lens; 7-sample cell;
8-sample particles; 9-a pulsed laser; 10-microscope objective;
11-an imaging device; 12 — a first coupling lens; 13-a first optical fiber;
14-laser induced breakdown spectroscopy; 15-a second coupling lens; 16 — a second optical fiber;
17-raman spectroscopy.
Detailed Description
Example 1
As shown in fig. 1 and fig. 2, the apparatus for chemical composition analysis of single suspended particles of the present embodiment includes a pulse laser 9, and further includes a hollow beam trapping particle system, an atomic emission spectrum collection system, a raman spectrum collection system, and an imaging system;
the hollow light beam particle capturing system comprises a continuous laser 1, a hollow light beam generating device 2, a beam expanding and collimating device, a high reflecting mirror 5 capable of changing the direction of a hollow light beam, a first converging lens 6 and a sample cell 7; the continuous laser 1, the hollow beam generating device 2, the beam expanding and collimating device, the high-reflection mirror 5 and the first convergent lens 6 are sequentially arranged on the same light path, and sample particles 8 are arranged in the sample cell 7;
the atomic emission spectrum acquisition system comprises a first coupling lens 12 and a laser-induced breakdown spectrometer 14 connected with the first coupling lens 12, wherein a first optical fiber 13 used for connecting the first coupling lens 12 and the laser-induced breakdown spectrometer 14 is arranged between the first coupling lens 12 and the laser-induced breakdown spectrometer 14;
the raman spectrum acquisition system comprises a second coupling lens 15 and a raman spectrometer 17 connected with the second coupling lens 15, and a second optical fiber 16 used for connecting the second coupling lens 15 and the raman spectrometer 17 is arranged between the second coupling lens 15 and the raman spectrometer 17;
the pulse light generated by the pulse laser 9 is perpendicular to the hollow light beam reflected by the high reflector 5; the pulse laser 9 is arranged in the direction vertical to the propagation direction of the hollow light beam reflected by the high reflector 5 and is positioned on the same plane with the sample cell 7;
the imaging system comprises an imaging device 11 and a microscope objective 10, wherein the microscope objective 10 is arranged between the imaging device 11 and the sample cell 7, and in the embodiment, the microscope objective 10 is a microscope objective with the magnification of 10 × being 0.25.
The continuous laser 1 is a 532nm semiconductor continuous laser, and can also be replaced by an all-solid-state tunable titanium sapphire dye continuous laser.
The hollow beam generating device 2 comprises a self-phase spatial beam modulation system, a cross-phase spatial beam modulation system, a biconic lens, a spatial light modulator or a phase plate which can generate a hollow beam.
As shown in fig. 3, the self-phase space light beam modulation system includes a first convex lens 2-1 and a non-linear absorbing medium 2-2 sequentially disposed on the same optical path, and a CCD camera for detecting the hollow light beam, which receives the light beam passing through the non-linear absorbing medium 2-2 and is movably disposed on the optical path.
In addition, a cross-phase spatial light beam modulation system can be adopted, wherein the cross-phase spatial light beam modulation system is the device for obtaining the Bessel light beam disclosed in the invention patent with the application number of '2016109453059' and the patent name of 'a method and a device for obtaining the Bessel light beam based on cross-phase modulation', the emission wavelength of laser is set to be 780.2100nm, and a hollow light beam is obtained;
hollow beams can also be obtained by means of biconic lenses, spatial light modulators or phase plates.
The beam expanding and collimating device comprises a second converging lens 3 and a third converging lens 4 which are positioned on the same optical path, and the second converging lens 3 is positioned between the hollow light beam generating device 2 and the third converging lens 4; in this embodiment, the focal length of the second converging lens 3 is 100mm, and the focal length of the third converging lens 4 is 200 mm; in addition, the device can be replaced by other beam expanding and collimating devices, such as a beam expander, a collimator and other optical systems capable of realizing laser beam expanding and collimating.
The imaging device 11 comprises a CCD camera, an ICCD camera or a CMOS camera; the imaging device in this embodiment is a CCD camera, which may be replaced with an ICCD camera or a CMOS camera.
The first focusing lens 6 is located between the high reflection mirror 5 and the sample cell 7, and in this embodiment, the focal length of the first focusing lens 6 is 30mm, and a microscope objective lens with a magnification of 10 × of 0.25 may be used instead.
The imaging device 11, the laser-induced breakdown spectrometer 14 and the raman spectrometer 17 are respectively positioned on different side parts of the sample cell 7; in this embodiment, the imaging device 11, the laser induced breakdown spectrometer 14, the pulse laser 9, the sample cell 7 and the raman spectrometer 17 are in the same plane, which is perpendicular to the hollow light beam reflected by the high reflecting mirror 5.
A method for chemical composition analysis of individual suspended particles using the apparatus of example 1, comprising the steps of:
step one, acquiring a continuous laser beam with Gaussian distribution from a continuous laser 1, and shaping the acquired continuous laser beam into a hollow beam through a hollow beam generating device 2; the hollow light beam is generated by a self-phase space light beam modulation system, a continuous laser beam with Gaussian distribution acquired from a continuous laser 1 is focused in a nonlinear absorption medium 2-2 through a first convex lens 2-1 to generate a hollow light beam, and the hollow light beam is detected by a CCD camera; the nonlinear absorption medium 2-2 is a rubidium atom pool, and can also be replaced by a lead glass or sodium atom pool;
step two, the hollow light beam obtained in the step one is incident to a high reflecting mirror 5 after passing through a beam expanding collimation device, the high reflecting mirror 5 is adjusted, the reflected hollow light beam is incident to a first convergent lens 6 to form a convergent hollow light beam, and the convergent hollow light beam is incident to a sample cell 7; the beam expanding and collimating process is that the hollow light beam obtained in the step one passes through a second converging lens 3 and then a third converging lens 4 to be subjected to beam expanding and collimating;
step three, obtaining a beam of converged pulse light from the pulse laser 9, adjusting the pulse laser 9 to enable the convergence center of the pulse light to coincide with the imaging center of the imaging device 11, and turning off the pulse laser 9;
step four, spraying sample particles 8 into the sample cell 7, capturing the sample particles 8 at the position of a light trap by the converged hollow light beam incident into the sample cell 7, and adjusting the light intensity and the size of the hollow light beam to enable the position of the light trap to coincide with the imaging center of the imaging device 11; the sample particles 8 used in the embodiment are alumina, the particle size is 2-10 μm, and other light-absorbing compounds can be used for replacement; in the embodiment, a self-phase space beam modulation system is adopted to generate a hollow beam, the power of a continuous laser 1 is adjusted to adjust the light intensity of the obtained hollow beam, and the size of the hollow beam is changed by changing the focal length of a first convex lens 2-1, so that the position of a light trap of the obtained hollow beam for capturing sample particles 8 coincides with an imaging center displayed by an imaging device 11;
the cross phase space light beam modulation system is used for generating a hollow light beam, and the light intensity and the size of the hollow light beam can be changed by rotating the angle of the half wave plate;
the hollow light beam is obtained through the biconical lens, and the light intensity of the hollow light beam can be changed by arranging the half-wave plate and the polarization beam splitter prism; changing the size of the hollow light beam by changing the vertex angle of the biconic lens;
the hollow light beam is obtained through the spatial light modulator or the phase plate, and the light intensity and the size of the hollow light beam can be changed by adjusting the output current of the spatial light modulator or adjusting the phase information of the phase plate;
adjusting the imaging system to amplify and record the movement of the sample particles 8 on the imaging device 11 through the microscope objective 10; the imaging is shot by a CCD camera, and an ICCD camera or a CMOS camera can be used for replacing the imaging;
fifthly, adjusting the position of the second coupling lens 15 to enable the second coupling lens 15 to collect scattered light generated by the sample particles 8, and displaying Raman spectrum information by a Raman spectrometer 17 connected with the second coupling lens 15;
step six, turning on the pulse laser 9 to ionize the captured sample particles 8 by the converged pulse light, and turning off the pulse laser 9;
and seventhly, adjusting the position of the first coupling lens 12 to enable the first coupling lens 12 to collect the atomic emission spectrum generated by ionization of the sample particles 8, and enabling the laser induced breakdown spectrometer 14 connected with the first coupling lens 12 to display information of the atomic emission spectrum.
And re-spraying sample particles into the sample pool 7 for repeated detection, comparing the spectrograms obtained for multiple times, and comparing the determined spectrogram with the standard spectrogram.
The above steps may be adjusted as desired.
Referring to FIGS. 4 and 5, the Raman spectra of the single-particle alumina obtained according to the present invention (FIG. 4) show peaks at 378cm-1、578-1And 645-1Corresponding to 376.9cm as shown in the standard Raman spectrum of alumina (FIG. 5)-1、575.9cm-1And 643.9cm-1Accordingly, it can be determined that the captured sample particles contain alumina species.
According to FIGS. 6 and 7, the laser-induced breakdown spectra of the single-particle alumina measured according to the present invention (FIG. 6) have peaks at 308.24nm and 309.31nm, and it can be determined that the captured sample contains aluminum element by comparison with the standard database of laser-induced breakdown spectra of the elements in FIG. 7.
The principle of the analysis method of the present invention is:
the invention is based on the basic principle of optical tweezers with optical swimming force. The method specifically comprises the following steps: when a beam of light irradiates the surface of the light-absorbing particles, the temperature of an irradiated area on the surface of the particles is increased, the thermal motion of gas molecules attached to the surface is intensified after the temperature of the irradiated area is increased, the gas molecules bounce off the surface of the particles at a higher speed, the thermal motion of the gas molecules on the irradiated surface is more violent than that of the molecules on the non-irradiated surface, and the particles generate a net acting force from the irradiated surface to the non-irradiated surface under the comprehensive action. According to aerodynamic principles, the pressure F of the molecules acting on the surface of the particles can be expressed as:
where ρ isaIs the density of air, kg/m3(ii) a B is a universal air constant, J/(mol. K); t is the particle surface temperature, K; m is the molar mass of the air molecule, kg/mol.
For a hollow beam, the force acting on the particle surface can be expressed as:
where ρ isaIs the density of air, kg/m3(ii) a B is a universal air constant, J/(mol. K); t is the particle surface temperature, K; m is the molar mass of air molecules, kg/mol; s is the area of the light-irradiated area on the particles, m2。
For irregular particles:
wherein,
is the average velocity of the air molecules, m/s; gamma ═ cp/cvIs the specific heat ratio; plIs the power of the incident hollow beam, W; p is the ambient gas pressure, N/m2(ii) a P is characteristic pressure, N/m2α is the thermal adaptation coefficient of the surface of the particles, Delta α is α1-α2，
Under the action of gravity, FΔTAnd FΔαCan be captured in the focal area, and F can be varied by adjusting the size of the hollow beamΔTThe force, in turn, manipulates the particles.
The captured particles are ionized by pulse light generated by a pulse laser, the spectrum of the electric particles is analyzed through an LIBS technology and a Raman spectrum, and meanwhile material composition information and element information of the particles are obtained.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and all simple modifications, changes and equivalent structural changes made to the above embodiment according to the technical spirit of the present invention still fall within the protection scope of the technical solution of the present invention.
Claims (6)
1. A method for single suspended particle chemical composition analysis using an analysis device comprising a pulsed laser (9), characterized in that: the analysis device also comprises a hollow beam particle capturing system, an atomic emission spectrum acquisition system, a Raman spectrum acquisition system and an imaging system;
the hollow beam particle capturing system comprises a continuous laser (1), a hollow beam generating device (2), a beam expanding and collimating device, a high reflecting mirror (5) capable of changing the direction of a hollow beam, a first converging lens (6) and a sample cell (7); the continuous laser (1), the hollow beam generating device (2), the beam expanding and collimating device, the high-reflection mirror (5) and the first convergent lens (6) are sequentially arranged on the same light path, and sample particles (8) are arranged in the sample cell (7); the hollow light beam generating device (2) is a self-phase space light beam modulation system capable of generating a hollow light beam, and the self-phase space light beam modulation system comprises a first convex lens (2-1), a nonlinear absorption medium (2-2) and a CCD (charge coupled device) camera, wherein the first convex lens and the nonlinear absorption medium are sequentially arranged on the same light path;
the atomic emission spectrum acquisition system comprises a first coupling lens (12) and a laser-induced breakdown spectrometer (14) connected with the first coupling lens (12), wherein a first optical fiber (13) used for connecting the first coupling lens (12) and the laser-induced breakdown spectrometer (14) is arranged between the first coupling lens (12) and the laser-induced breakdown spectrometer (14);
the Raman spectrum acquisition system comprises a second coupling lens (15) and a Raman spectrometer (17) connected with the second coupling lens (15), and a second optical fiber (16) used for connecting the second coupling lens (15) and the Raman spectrometer (17) is arranged between the second coupling lens (15) and the Raman spectrometer (17);
the pulse light generated by the pulse laser (9) is vertical to the hollow light beam reflected by the high reflector (5);
the imaging system comprises an imaging device (11) and a microscope objective (10), the microscope objective (10) being arranged between the imaging device (11) and the sample cell (7);
the method comprises the following steps:
step one, acquiring a continuous laser beam with Gaussian distribution from a continuous laser (1), and shaping the acquired continuous laser beam into a hollow beam through a hollow beam generating device (2);
step two, the hollow light beam obtained in the step one is incident to a high reflecting mirror (5) after passing through a beam expanding and collimating device, the high reflecting mirror (5) is adjusted, the reflected hollow light beam is incident to a first converging lens (6) to form a converged hollow light beam, and the converged hollow light beam is incident to a sample cell (7);
step three, obtaining a beam of convergent pulsed light from a pulse laser (9), enabling the convergence center of the pulsed light to coincide with the imaging center of an imaging device (11), and turning off the pulse laser (9);
step four, spraying sample particles (8) into the sample cell (7), capturing the sample particles (8) at the position of an optical trap by the converged hollow light beam incident into the sample cell (7), and adjusting the light intensity and the size of the hollow light beam to enable the position of the optical trap to coincide with the imaging center of the imaging device (11);
step five, collecting scattered light generated by the sample particles (8) by a second coupling lens (15), and displaying Raman spectrum information by a Raman spectrometer (17);
sixthly, turning on a pulse laser (9) to enable the converged pulse light to ionize the captured sample particles (8), and turning off the pulse laser (9);
and seventhly, acquiring an atomic emission spectrum generated by ionization of the sample particles (8) by using the first coupling lens (12), and displaying information of the atomic emission spectrum by using the laser-induced breakdown spectrometer (14).
2. A method for chemical composition analysis of individual suspended particles using an analytical device according to claim 1, wherein: the continuous laser (1) is a 532nm semiconductor continuous laser or an all-solid-state tunable titanium sapphire dye continuous laser.
3. A method for chemical composition analysis of individual suspended particles using an analytical device according to claim 1, wherein: the beam expanding and collimating device comprises a second converging lens (3) and a third converging lens (4) which are positioned on the same optical path, and the second converging lens (3) is positioned between the hollow light beam generating device (2) and the third converging lens (4).
4. A method for chemical composition analysis of individual suspended particles using an analytical device according to claim 1, wherein: the imaging device (11), the laser-induced breakdown spectrometer (14) and the Raman spectrometer (17) are respectively positioned on different sides of the sample cell (7).
5. A method for chemical composition analysis of individual suspended particles using an analytical device according to claim 1, wherein: the imaging device (11) comprises a CCD camera, an ICCD camera or a CMOS camera.
6. A method for chemical composition analysis of individual suspended particles using an analytical device according to claim 1, wherein: the first convergent lens (6) is positioned between the high reflection mirror (5) and the sample cell (7).
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| KR20210016716A (en) * | 2019-08-05 | 2021-02-17 | 삼성전자주식회사 | Particulate matter measurement apparatus and method |
| CN111077060A (en) * | 2019-12-31 | 2020-04-28 | 天津大学 | Single particle detection system based on Raman and laser-induced breakdown spectroscopy integration |
| CN111044420B (en) * | 2020-01-03 | 2022-02-11 | 南京信息工程大学 | LIBS and Raman spectrum aerosol on-line detection device based on single particle |
| CN111366510B (en) * | 2020-03-02 | 2022-06-03 | 清华大学深圳国际研究生院 | Suspended particulate matter flux measuring device utilizing synchronous polarization and fluorescence |
| CN111855505B (en) * | 2020-07-07 | 2021-12-28 | 浙江大学 | Microsphere cluster state detection device and detection method applied to vacuum optical trap system |
| CN112649595B (en) * | 2020-11-11 | 2022-02-22 | 西安交通大学 | System and method based on single-pulse laser-induced photoinduced breakdown controllable jet flow |
| CN113804606B (en) * | 2021-08-26 | 2024-07-12 | 之江实验室 | Suspended optical trap nanoparticle quality measurement method based on electric field calibration |
| CN114205929B (en) * | 2022-02-15 | 2022-08-05 | 之江实验室 | Infrared optical system for heating suspended nanoparticles |
| CN115452804B (en) * | 2022-11-10 | 2023-01-31 | 泉州师范学院 | Raman spectrum detection device and method for body fluid |
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| US9222874B2 (en) * | 2012-06-27 | 2015-12-29 | The United States Of America As Represented By The Secretary Of The Army | Systems and methods for individually trapping particles from air and measuring the optical spectra or other properties of individual trapped particles |
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| CN106932914A (en) * | 2017-04-17 | 2017-07-07 | 鲁东大学 | A kind of production method and device of cubical array hollow light spot |
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