Portable laser-induced breakdown spectroscopy collection device and control method

Abstract

The invention relates to the field of laser-induced breakdown spectroscopy collection, in particular to a portable laser-induced breakdown spectroscopy collection device and a control method, and the laser-induced breakdown spectroscopy collection device comprises a laser emitting device, a sample bearing mechanism and a collection mechanism; the laser emitting mechanism is used for emitting laser beams; the sample bearing mechanism comprises a sample bearing plate; the collecting mechanism comprises a supporting frame body, a plurality of collecting assemblies and a plurality of adjusting units, the supporting frame body is provided with a laser channel axis allowing a laser beam to penetrate through, and the adjusting units are arranged corresponding to the collecting assemblies; each adjusting unit comprises a linear driving mechanism used for driving the collecting head to linearly reciprocate in the radial direction pointing to the axis of the laser channel, and an angle adjusting mechanism used for adjusting the included angle between the optical axis of the collecting head and the plane where the sample bearing plate is located. The technical effects that the signal light generated by the plasma is comprehensively collected from multiple angles, and the stability and comprehensiveness of signal light collection are improved are achieved.

Description

Technical Field

[0001] The present application relates to the technical field of laser induced breakdown spectroscopy acquisition, and in particular to a portable laser induced breakdown spectroscopy acquisition device and a control method. Background Art

[0002] Laser-induced breakdown spectroscopy (LIBS) is an atomic emission spectroscopic analysis technique that uses a pulsed laser to generate a plasma on the surface of a sample. The wavelength and intensity of the plasma's emission spectrum are then analyzed to determine the element types and concentrations in the sample. This technique requires no sample preparation, offers rapid analysis speed, is remote and non-contact, and can simultaneously analyze multiple elements in any substance. Therefore, it is widely used in a wide range of fields, including metal analysis, environmental monitoring, atomic energy and nuclear engineering, life sciences, and cultural relic preservation.

[0003] In the traditional laser-induced breakdown spectroscopy acquisition process, in order to collect the signal light generated by the sample when the sample is excited by the laser, a fixed frame is used to place the sample and the laser emission mechanism, and there is a lack of precise restriction measures on the path of the laser beam. However, the existing technology has obvious defects. The plasma formed by the laser beam on the sample is not completely uniform in space, and each excitation may have slight morphological changes. If only one acquisition component is used to collect signal light from a single angle, the intensity of the collected signal light will fluctuate greatly due to this unevenness and instability, resulting in incomplete collection. Summary of the Invention

[0004] The purpose of this application is to overcome the above technical problems and provide a portable laser induced breakdown spectroscopy acquisition device.

[0005] A portable laser-induced breakdown spectroscopy acquisition device, comprising: A laser emitting mechanism, for emitting a laser beam; A sample carrying mechanism, comprising a sample carrying plate for carrying the sample; Collection agencies include: A support frame, wherein the support frame is provided with a laser channel axis for the laser beam to pass through; a plurality of collection components, the plurality of collection components being arranged in a circular array around the axis of the laser channel, each of the collection components comprising a collection head for collecting plasma signal light generated by the laser beam irradiating the sample; and A plurality of adjustment units, each of which is respectively provided corresponding to one of the collection components and is used to adjust the position and posture of the corresponding collection head; Wherein, each of the adjustment units comprises: A linear drive mechanism, configured to drive the acquisition head to perform linear reciprocating motion in a radial direction generally pointing toward the axis of the laser channel; and The angle adjustment mechanism is used to adjust the angle between the optical axis of the collection head and the plane where the sample supporting plate is located.

[0006] By adopting the above scheme, the plasma formed by the laser beam on the sample is not completely uniform in space and may experience slight morphological changes with each excitation. If only a single collection component is used to collect signal light from a single angle, the intensity of the collected signal light will fluctuate significantly due to this unevenness and instability, resulting in incomplete collection. Multiple collection components arranged in a circular array can collect the signal light generated by the plasma from multiple angles. At the same time, the angles and distances from the laser channel of each collection component can be changed, increasing the collection range and thus enabling more comprehensive signal light collection.

[0007] In one embodiment, the linear drive mechanism comprises: a sliding frame, on which the collecting head and the angle adjustment mechanism are mounted; and An adjusting screw rod is driven by a power source and is transmission-connected to the sliding frame to drive the sliding frame to move linearly.

[0008] By adopting the above solution, the position of the plasma will change when analyzing samples of different shapes or when the distance between the entire device and the sample changes. The adjustment screw can drive the sliding frame and the collection head to move during rotation, so that the collection head can refocus on the plasma. When the sample to be analyzed is a curved surface or is obscured, the optimal collection point can also be found by adjusting the position of the collection head.

[0009] In one embodiment, a rotating frame, the collecting head is mounted on the rotating frame, and the rotating frame is rotatably connected to the sliding frame; and A telescopic member, one end of which is hinged to the sliding frame, and the other end of which is hinged to the rotating frame, is used to drive the rotating frame to rotate by changing its own length.

[0010] By adopting the above solution, the telescopic member can drive the rotating frame to rotate around one end of the sliding frame during the telescopic process, thereby changing the angle of the collection head, so that the collection head can aim at the collection signal light generated by plasma at different heights.

[0011] In one embodiment, the support plate group includes two parallel support plates, an adjustment portion is formed between the two parallel support plates, the collection component is located in the adjustment portion, and a mounting frame with a "U"-shaped cross-section is provided on one side of the adjustment portion, the adjustment screw rod passes through both ends of the mounting frame, and a plurality of guide rods parallel to the adjustment screw rod are fixed in the mounting frame, and the guide rods pass through the sliding block.

[0012] By adopting the above solution, the adjustment part separates the multiple collection components, plays the role of installation and limiting the collection components, and through the setting of the mounting frame and the guide rod, the movement trajectory of the collection components is preliminarily prevented from deflecting.

[0013] In one embodiment, a first guide rail parallel to the adjusting screw is fixedly provided on a side of the adjusting portion facing away from the mounting frame, a second guide rail parallel to the adjusting screw is fixedly provided on a side of the lower connecting plate facing the adjusting portion, a first slider cooperating with the first guide rail is fixedly provided on one side of the sliding frame, and a second slider cooperating with the second guide rail is provided at the bottom of the sliding frame.

[0014] By adopting the above solution, the guide rod, the first guide rail and the second guide rail cooperate with each other to limit the two sides and the bottom of the sliding frame at the same time, and at the same time support the sliding frame to prevent the sliding frame from deviating from the displacement trajectory due to its own deformation.

[0015] In one embodiment, a plurality of sleeve clamps that cooperate with the outer peripheral surface of the collection head are provided in the mounting groove, and a mounting screw hole is provided on the surface of each sleeve clamp facing the bottom of the mounting groove, and a mounting bolt that cooperates with the mounting screw hole is provided at one end of the rotating frame away from the sleeve clamp.

[0016] By adopting the above solution, the collection head is fixed by the cooperation of the sleeve clamp and the mounting bolt.

[0017] In one embodiment, adjustment screws are provided on both sides of the rotating frame, and the adjustment screws pass through both sides of the rotating frame and abut against both sides of the sleeve clamp. An adjustment groove is provided at the bottom of the rotating frame, and the adjustment groove is arc-shaped. The mounting bolt passes through the adjustment groove and cooperates with the mounting screw hole.

[0018] By adopting the above solution, the adjusting screw is used to limit the sleeve clamp to prevent the sleeve clamp from shaking left and right. At the same time, the mounting bolt passes through different positions of the adjustment slot, and the collection head is fixed by the sleeve clamp at different angles, further improving the freedom of angle adjustment of the collection head.

[0019] In one embodiment, the sample supporting mechanism further includes a supporting column, a first driving screw is disposed in the supporting column, and the first driving screw passes through the sample supporting plate.

[0020] By adopting the above solution, the first driving screw can drive the sample supporting plate to move along the supporting column when it rotates, so that the sample can be adjusted to the most suitable collection height.

[0021] In one embodiment, the sample supporting mechanism also includes an adjustment base located at the bottom of the supporting column, and the adjustment base includes a first adjustment plate and a second adjustment plate arranged perpendicular to each other. The first adjustment plate is provided with a second drive screw passing through the supporting column, and the second drive screw is perpendicular to the first drive screw. The second adjustment plate is provided with a third drive screw passing through the first adjustment plate, and the third drive screw is perpendicular to the plane where the first drive screw and the second drive screw are located.

[0022] By adopting the above solution, when the sample has other observation requirements, the adjustment base can adjust the working position of the sample detection, thereby facilitating the installation of other observation equipment.

[0023] The present application also provides a control method for a portable laser-induced breakdown spectroscopy acquisition device, which comprises the following steps: S1. Controlling the laser emitting mechanism to emit a laser beam, the laser beam is irradiated along a preset laser channel axis onto the sample carried by the sample supporting plate to excite and generate plasma on the sample surface; S2. According to the position of the sample or plasma, the linear drive mechanism in each adjustment unit is controlled to drive the corresponding collection head to move in a radial direction generally pointing to the axis of the laser channel to focus the collection head on the plasma; S3. According to the height or shape of the plasma, control the angle adjustment mechanism in each adjustment unit to adjust the angle between the optical axis of the corresponding collection head and the plane of the sample carrier plate so that the collection head aims at the optimal collection area of ​​the plasma signal light; S4. By using a plurality of collection heads arranged in a circular array around the axis of the laser channel, the signal light emitted by the plasma is synchronously collected from a plurality of different angles and positions to achieve comprehensive collection of the signal light.

[0024] By adopting the above solution, the device can adapt to samples of different shapes or that are obscured, and synchronously collect signals from multiple angles, ultimately obtaining more comprehensive, stable and high-quality spectral data.

[0025] In summary, this application includes at least one of the following beneficial technical effects: 1. Because the plasma formed by the laser beam on the sample is not completely uniform in space and may experience slight morphological changes with each excitation, using only one acquisition component to collect signal light from a single angle will result in significant fluctuations in the intensity of the collected signal light due to this unevenness and instability, resulting in incomplete collection. Multiple acquisition components arranged in a circular array can collect the signal light generated by the plasma from multiple angles, increasing the collection range and enabling more comprehensive signal light collection. Furthermore, the two laser perforations can restrict the path of the laser beam, preventing deviations in the laser irradiation position.

[0026] 2. During the extension and retraction process, the telescopic part can drive the rotating frame to rotate around one end of the sliding frame, thereby changing the angle of the collection head, so that the collection head can aim at the collection signal light generated by the plasma at different heights. When analyzing samples of different shapes, or the distance between the entire device and the sample changes, the position of the plasma will also change. The adjustment screw can drive the sliding block to move during the rotation process, and the sliding block can drive the sliding frame and the collection head to move, so that the collection head can refocus on the plasma. When the analyzed sample is a curved surface or is blocked, the best collection point can also be found by adjusting the position of the collection head.

[0027] 3. Through the setting of the sample carrying mechanism, when the sample has other observation requirements, the adjustment base can adjust the working position of the sample detection, thereby facilitating the installation of other observation equipment. When the first driving screw rotates, it can drive the sample carrying plate to move along the carrying column, so that the sample can be adjusted to the most suitable collection height. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic structural diagram of a portable laser-induced breakdown spectroscopy acquisition device provided in this application.

[0029] Figure 2 It is a schematic diagram of the connection relationship between the support frame and the collection component.

[0030] Figure 3 It is a schematic diagram of the internal structure of the support frame.

[0031] Figure 4 It is a structural diagram of the acquisition component.

[0032] Figure 5 This is an exploded view of the acquisition component.

[0033] Explanation of reference numerals: 1. laser emitting mechanism; 2. sample carrying mechanism; 21. sample carrying plate; 22. carrying column; 221. first driving screw; 23. adjusting base; 231. first adjusting plate; 2311. second driving screw; 232. second adjusting plate; 2321. third driving screw; 3. collecting mechanism; 31. supporting frame; 311. upper connecting plate; 312. lower connecting plate; 3121. observation hole; 313. supporting plate assembly; 3131. adjusting portion; 3132. first guide rail; 3133. second guide rail; 314. laser perforation; 32 , collection component; 321, collection head; 33, adjustment unit; 331, sliding frame; 3311, sliding block; 3312, first slider; 3313, second slider; 332, rotating frame; 3321, mounting slot; 3322, adjusting top screw; 3323, adjusting slot; 3324, mounting bolt; 333, telescopic member; 334, adjusting screw rod; 3341, power source; 335, mounting frame; 3351, guide rod; 336, sleeve clamp; 3361, mounting screw hole; 34, linear drive mechanism; 35, angle adjustment mechanism; 4, cage structure connecting block. DETAILED DESCRIPTION

[0034] Therefore, it is necessary to provide a laser induced breakdown spectroscopy acquisition device that can accurately capture signal light.

[0035] Example 1: Please refer to Figure 1-2 , Figure 1 The present invention provides a schematic structural diagram of a portable laser-induced breakdown spectroscopy acquisition device. The laser-induced breakdown spectroscopy acquisition device provided in the present invention includes a laser emitting mechanism 1, a sample supporting mechanism 2, and an acquisition mechanism 3. The laser emitting mechanism 1 is used to emit a laser beam, the sample supporting mechanism 2 includes a sample supporting plate 21 for supporting a sample, and the acquisition mechanism 3 includes a support frame 31 and multiple acquisition components 32. Each acquisition component 32 includes a collection head 321, and each acquisition component 32 is correspondingly provided with an adjustment unit 33. The adjustment unit 33 includes a linear drive mechanism 34 and an angle adjustment mechanism 35. Since the laser-induced plasma itself is a three-dimensional, non-uniform luminous area, its shape, size, and luminous intensity will change with time, spatial position, and subtle differences in each laser pulse. A single acquisition component 32 can only collect the signal light generated by the plasma from a single angle, and the collected signal is not stable and comprehensive enough. By providing multiple acquisition components 32, the multiple acquisition components 32 can collect the signal light generated by the plasma from multiple perspectives, making the measurement results more accurate.

[0036] The sample support mechanism 2 includes a sample support plate 21 and a support column 22. The sample support plate 21 is positioned below the support frame 31 and is slidably connected to the support column 22. A first drive screw 221 is located within the support column 22 to drive the sample support plate 21 up and down. The first drive screw 221 can be driven by a motor. When the first drive screw 221 rotates, it moves the sample support plate 21 along the support column 22, thereby adjusting the sample to the optimal collection height. The sample support mechanism 2 also includes an adjustment base 23, which includes a first adjustment plate 231 and a second adjustment plate 232, which are arranged vertically. The first adjustment plate 231 includes a second drive screw 2311 perpendicular to the first drive screw 221. The second adjustment plate 232 includes a third drive screw 2321 perpendicular to the first drive screw 221 and a flat surface. If additional observation of the sample is required, the sample's working position can be adjusted by controlling the rotation of the second and third drive screws 2311, 2321, thereby facilitating the installation of other observation equipment.

[0037] The support frame 31 comprises an upper connecting plate 311, a lower connecting plate 312 arranged parallel to the upper connecting plate 311, and a plurality of supporting plate groups 313 arranged in a circular array. The upper connecting plate 311 and the lower connecting plate 312 are each provided with a coaxial laser perforation 314. Multiple collection assemblies 32 are arranged in a circular array centered around the axis of the laser perforation 314. Each collection assembly 32 is used to collect the signal light generated by the laser beam acting on the sample, thereby increasing the collection range and comprehensively collecting the signal light while simultaneously limiting the laser beam path and avoiding deviations in the irradiation position. This is because the plasma formed by the laser beam on the sample is not completely uniform in space and may undergo slight morphological changes with each excitation. The multiple collection assemblies 32 arranged in a circular array can collect the signal light generated by the plasma from multiple angles, while the two laser perforations 314 can limit the laser beam path.

[0038] Please also refer to Figure 3 , Figure 3It is a schematic diagram of the internal structure of the support frame. The upper connecting plate 311 and the lower connecting plate 312 of the support frame 31 are generally made of metal, such as aluminum alloy, which has good strength and stability. The upper connecting plate 311 and the lower connecting plate 312 are arranged in parallel to ensure the coaxiality of the laser perforation 314. Multiple support plate groups 313 are distributed in a circular array and are perpendicular to the upper connecting plate 311, which play the role of connecting and supporting the upper connecting plate 311 and the lower connecting plate 312. The support plate group 313 can be made of steel plates or high-strength plastic plates, and the support plates in the support plate group 313 can be fixed by welding or bolting. The laser emitting mechanism 1 includes a pulsed laser and a focusing lens. The pulsed laser can generate a high-energy laser beam to meet the needs of laser induced breakdown spectroscopy analysis. The focusing lens is used to guide the laser beam to pass through the two laser perforations 314, and at the same time focus the laser beam on the sample to be tested, so that the surface of the sample to be tested is excited to generate a plasma that emits signal light for detection.

[0039] In this application, a cage-type connecting block 4 is mounted on the side of the lower connecting plate 312 facing away from the support plate assembly 313. This connecting block 4 is used to connect to other cage-type connecting columns in the experimental equipment, integrating the support frame 31 and multiple collection components 32 into a classic cage-type optical system, ensuring compatibility with traditional optical experimental systems. The center of the cage-type connecting block 4 is coaxial with the central axis of the two laser perforations 314. The connecting block's lower surface is connected to the connecting plate 311 by bolts. The lower connecting plate 312 also has an observation hole 3121 for observing the collection components 32.

[0040] Please also refer to Figure 4-5 , Figure 4 The figure is a schematic diagram of the structure of the collection component. The collection head 321 is carried by the adjustment unit 33. The collection head 321 passes through the observation hole 3121 of the lower connecting plate 312 and is used to collect the signal light generated by the plasma. The adjustment unit 33 is used to change the angle and orientation of the collection head 321. Because the signal light generated by the plasma is not uniform, the intensity of the signal light generated in different areas is also different. If the collection direction of the collection head 321 converges at only one point, it will lead to inaccurate quantitative analysis of the signal light. The angle and orientation of multiple collection heads 321 can be adjusted, and each collection head 321 can collect signal light from different areas, thereby obtaining higher-quality spectral data.

[0041] The linear drive mechanism 34 includes a sliding frame 331 and an adjustment screw 334 driven by a power source 3341. The power source 3341 can be a stepper motor. The stepper motor has the advantage of no accumulated error, which facilitates repeated positioning during horizontal movement. The adjustment screw 334 is parallel to the plane where the collection head 321 and the telescopic member 333 are located. A sliding block 3311 that cooperates with the adjustment screw 334 is provided on one side of the sliding frame 331. When the adjustment screw 334 rotates, the sliding block 3311 will move on the screw, thereby driving the sliding frame 331 and the collection head 321 to move. The adjustment screw 334 can adopt a ball screw, which has high transmission efficiency and precision.

[0042] The angle adjustment mechanism 35 includes a rotating frame 332 and a telescopic member 333. The rotating frame 332 is provided with a mounting slot 3321, and the collection head 321 is disposed within the mounting slot 3321. One end of the rotating frame 332 is rotatably connected to one end of the sliding frame 331 via a rotating shaft, enabling the rotating frame 332 to rotate about the sliding shaft. The telescopic member 333 can be an electric push rod or a hydraulic telescopic rod, with its ends rotatably connected to the rotating frame 332 and the sliding frame 331, respectively. During the extension and retraction of the telescopic member 333, the rotating frame 332 can be driven to rotate about one end of the sliding frame 331, thereby changing the angle of the collection head 321, allowing the collection head 321 to aim at the collection signal light generated by plasma at different heights. The laser emitting mechanism 1 focuses the laser beam near the test point of the sample to be tested, generating high-temperature plasma at the test point. The plasma emits signal light, and the collection module within the collection head 321 collects the signal light generated by the plasma.

[0043] In this application, the acquisition module of acquisition head 321 is installed within a lens sleeve, which serves as a standard interface for various optical signal acquisition devices. It can accommodate various lenses and optical sensors that meet size requirements. This lens sleeve collects and processes plasma optical signals, including but not limited to focusing and color filtering. The sleeve also features threads at the rear end, allowing for convenient installation of connectors for various optical acquisition devices or connecting optical fibers.

[0044] Telescopic member 333 uses an electric push rod with a built-in encoder for precise closed-loop length control. The push rod driver and control module are used to drive and control the push rod. Electric push rods often use DC reduction motors. The driver can use discrete components to form a classic H-bridge circuit, or an integrated motor control chip. The control section can simply lead the control lines of the drive circuit directly. For circuit reliability, it can also be controlled through an optocoupler. The control signals and the push rod's position feedback signals can be directly processed by a PLC or MCU, while leaving digital signal interfaces such as serial ports to facilitate the implementation of the host computer control structure and simplify system design.

[0045] The support plate group 313 includes two support plates arranged in parallel, and an adjustment portion 3131 is formed between the two support plates. A mounting frame 335 is provided in the adjustment portion 3131, and the mounting frame 335 can adopt a metal frame structure. The adjusting screw 334 passes through the mounting frame 335 and is rotatably connected to the mounting frame 335. A guide rod 3351 parallel to the adjusting screw 334 is fixed in the mounting frame 335, and the guide rod 3351 passes through the sliding block 3311 on the sliding frame 331. The guide rod 3351 can be a smooth metal rod, which guides the movement of the sliding block 3311 and prevents it from deviating. In the present application, a position encoder such as a grating ruler can also be provided on the mounting frame 335 to detect the absolute horizontal position of the horizontal frame, realize closed-loop control, and improve the motion accuracy of the acquisition head 321.

[0046] A first guide rail 3132 is provided on the side of the adjustment portion 3131 facing away from the mounting frame 335. A second guide rail 3133 is provided on the side of the lower connecting plate 312 corresponding to the adjustment portion 3131. The sliding frame 331 is provided with a first slider 3312 that cooperates with the first guide rail 3132 and a second slider 3313 that cooperates with the second guide rail 3133. The first and second guide rails 3132, 3133 can be dovetail guide rails or linear guide rails. The first and second sliders 3312, 3313 are adapted to the guide rails and can slide smoothly on them. The guide rod 3351, the first and second guide rails 3132, 3133 cooperate with each other to simultaneously limit the sides and bottom of the sliding frame 331, while also providing support for the sliding frame 331, preventing the sliding frame 331 from deviating from its displacement trajectory due to deformation.

[0047] The rotating frame 332 has a mounting slot 3321, within which is located a sleeve fixture 336 that mates with the outer circumference of the collection head 321. The sleeve fixture 336 can be made of rubber or plastic, which has a certain degree of elasticity and can better conform to the outer circumference of the collection head 321. The bottom of the sleeve fixture 336 has a mounting screw hole 3361, and the rotating frame 332 has a mounting bolt 3324 that mates with the mounting screw hole 3361. Tightening the mounting bolt 3324 secures the collection head 321 to the rotating frame 332.

[0048] Adjustment screws 3322 are provided on both sides of the rotating frame 332, which abut against the sleeve clamp 336. The adjustment screws 3322 can be metal screws. By rotating the adjustment screws 3322, the sleeve clamp 336 can be positioned to prevent the sleeve clamp 336 from rocking left or right. A circular arc-shaped adjustment slot 3323 is provided at the bottom of the rotating frame 332. A mounting bolt 3324 passes through the adjustment slot 3323 and engages with the mounting screw hole 3361. By passing the mounting bolt 3324 through different positions of the adjustment slot 3323, the collection head 321 is secured by the sleeve clamp 336 at different angles, further increasing the freedom of angle adjustment of the collection head 321.

[0049] The operating principle of this embodiment is as follows: the laser-induced breakdown spectroscopy acquisition device uses multiple acquisition devices distributed in a circular array to collect signal light generated by the plasma from multiple angles, expanding the acquisition range and enabling more comprehensive signal light collection. Furthermore, two laser perforations 314 in the support frame 31 restrict the path of the laser beam, preventing deviations in the laser irradiation position. An adjustment unit 33 adjusts the position and angle of the acquisition head 321 to accommodate samples of varying shapes and different acquisition requirements.

[0050] Example 2: This application also provides a control method for a portable laser-induced breakdown spectroscopy acquisition device, which includes the following steps: S1. Controlling the laser emitting mechanism 1 to emit a laser beam, the laser beam is irradiated along a preset laser channel axis onto the sample carried by the sample supporting plate 21 to excite and generate plasma on the sample surface; S2. According to the position of the sample or plasma, the linear drive mechanism 34 in each adjustment unit 33 is controlled to drive its corresponding collection head 321 to move in a radial direction generally pointing to the axis of the laser channel to align the focus of the collection head 321 with the plasma; S3. According to the height or shape of the plasma, the angle adjustment mechanism 35 in each adjustment unit 33 is controlled to adjust the angle between the optical axis of the corresponding collection head 321 and the plane of the sample carrier plate 21, so that the collection head 321 is aimed at the optimal collection area of ​​the plasma signal light; S4. The signal light emitted by the plasma is synchronously collected from multiple angles and positions by a plurality of collection heads 321 arranged in a circular array around the axis of the laser channel to achieve comprehensive collection of the signal light.

[0051] Through this control method, the laser-induced breakdown spectroscopy acquisition device can independently and precisely control multiple adjustment units 33 based on sample characteristics or plasma morphology. By controlling the linear drive mechanism 34, the acquisition head 321 can be adjusted to the optimal distance from the plasma for precise focusing. By controlling the angle adjustment mechanism 35, the pitch of the acquisition head 321 can be changed to target the plasma region with the strongest signal. This flexible control strategy enables the device to adapt to samples of varying shapes or obscurations, and to simultaneously acquire signals from multiple angles, ultimately obtaining more comprehensive, stable, and high-quality spectral data.

[0052] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A portable laser induced breakdown spectroscopy acquisition device, characterized in that: include: A laser emitting mechanism (1) for emitting a laser beam; A sample carrying mechanism (2) comprising a sample carrying plate (21) for carrying the sample; Collection agencies (3), including: A support frame (31), wherein the support frame (31) is provided with a laser channel axis for the laser beam to pass through; a plurality of collection components (32), the plurality of collection components (32) being arranged in a circular array around the axis of the laser channel, each of the collection components (32) comprising a collection head (321) for collecting plasma signal light generated by the laser beam irradiating the sample; and A plurality of adjustment units (33), each adjustment unit (33) is respectively provided corresponding to one of the collection components (32) and is used to adjust the position and posture of the corresponding collection head (321); Wherein, each of the regulating units (33) comprises: A linear drive mechanism (34) for driving the collection head (321) to perform linear reciprocating motion along a radial direction generally pointing to the axis of the laser channel; and An angle adjustment mechanism (35) is used to adjust the angle between the optical axis of the collection head (321) and the plane where the sample supporting plate (21) is located.

2. The portable laser induced breakdown spectroscopy acquisition device according to claim 1, characterized in that: The linear drive mechanism (34) comprises: a sliding frame (331), the collecting head (321) and the angle adjustment mechanism are both mounted on the sliding frame (331); and An adjusting screw rod (334) driven by a power source (3341) is connected in a transmission manner to the sliding frame (331) to drive the sliding frame (331) to move linearly.

3. The portable laser induced breakdown spectroscopy acquisition device according to claim 2, characterized in that: The angle adjustment mechanism (35) comprises: a rotating frame (332), the collecting head (321) is mounted on the rotating frame (332), and the rotating frame (332) is rotatably connected to the sliding frame (331); and A telescopic member (333), one end of which is hinged to the sliding frame (331), and the other end of which is hinged to the rotating frame (332), is used to drive the rotating frame (332) to rotate by changing its own length.

4. The portable laser-induced breakdown spectroscopy acquisition device according to claim 2, characterized in that: The support frame body comprises an upper connecting plate (311), a lower connecting plate (312) arranged parallel to the upper connecting plate (311), and a plurality of supporting plate groups (313) arranged in a circumferential array. Each of the supporting plate groups (313) comprises two supporting plates arranged in parallel. An adjusting portion (3131) is formed between the two parallel supporting plates. The collecting assembly (32) and the adjusting unit (33) are both located in the adjusting portion (3131). A mounting frame (335) with a U-shaped cross section is provided on one side of the adjusting portion (3131). The adjusting screw rod (334) passes through both ends of the mounting frame (335). A plurality of guide rods (3351) arranged parallel to the adjusting screw rod (334) are fixed in the mounting frame (335). The guide rods (3351) pass through the sliding frame (331).

5. The portable laser-induced breakdown spectroscopy acquisition device according to claim 4, characterized in that: A first guide rail (3132) parallel to the adjusting screw rod (334) is fixedly provided on the side of the adjusting portion (3131) facing away from the mounting frame (335); a second guide rail (3133) parallel to the adjusting screw rod (334) is fixedly provided on the side of the lower connecting plate (312) facing the adjusting portion (3131); a first slider (3312) cooperating with the first guide rail (3132) is fixedly provided on one side of the sliding frame (331); and a second slider (3313) cooperating with the second guide rail (3133) is provided at the bottom of the sliding frame (331).

6. The portable laser-induced breakdown spectroscopy acquisition device according to claim 3, characterized in that: The rotating frame (332) is provided with a mounting groove (3321), and a plurality of sleeve clamps (336) are provided in the mounting groove (3321) and matched with the outer peripheral surface of the collection head (321). Each sleeve clamp (336) is provided with a mounting screw hole (3361) on the surface facing the bottom of the mounting groove (3321), and a mounting bolt (3324) matching with the mounting screw hole (3361) is provided at one end of the rotating frame (332) away from the sleeve clamp (336).

7. The portable laser-induced breakdown spectroscopy acquisition device according to claim 6, characterized in that: Adjustment screws (3322) are provided on both sides of the rotating frame (332), and the adjustment screws (3322) pass through both sides of the rotating frame (332) and abut against both sides of the sleeve clamp (336). An adjustment groove (3323) is provided at the bottom of the rotating frame (332), and the adjustment groove (3323) is in an arc shape. The mounting bolt (3324) passes through the adjustment groove (3323) and cooperates with the mounting screw hole (3361).

8. The portable laser-induced breakdown spectroscopy acquisition device according to claim 1, characterized in that: The sample carrying mechanism (2) further comprises a carrying column (22), a first driving screw (221) being arranged in the carrying column (22), and the first driving screw (221) passing through the sample carrying plate (21).

9. The portable laser-induced breakdown spectroscopy acquisition device according to claim 8, characterized in that: The sample supporting mechanism (2) further comprises an adjustment base (23) located at the bottom of the supporting column (22), the adjustment base (23) comprising a first adjustment plate (231) and a second adjustment plate (232) arranged perpendicular to each other, the first adjustment plate (231) being provided with a second driving screw (2311) passing through the supporting column (22), the second driving screw (2311) being perpendicular to the first driving screw (221), the second adjustment plate (232) being provided with a third driving screw (2321) passing through the first adjustment plate (231), the third driving screw (2321) being perpendicular to the plane where the first driving screw (221) and the second driving screw (2311) are located.

10. The control method of a portable laser-induced breakdown spectroscopy acquisition device according to claim 1, characterized in that: It includes the following steps: S1. Controlling the laser emitting mechanism (1) to emit a laser beam, wherein the laser beam is irradiated along a preset laser channel axis onto the sample carried by the sample supporting plate (21) to excite and generate plasma on the sample surface; S2. According to the position of the sample or plasma, the linear drive mechanism (34) in each adjustment unit (33) is controlled to drive the corresponding collection head (321) to move in a radial direction generally pointing to the axis of the laser channel, so as to align the focus of the collection head (321) with the plasma; S3. According to the height or shape of the plasma, the angle adjustment mechanism (35) in each adjustment unit (33) is controlled to adjust the angle between the optical axis of the corresponding collection head (321) and the plane of the sample carrier plate (21) so that the collection head (321) is aimed at the optimal collection area of ​​the plasma signal light; S4. The signal light emitted by the plasma is synchronously collected from multiple different angles and positions by a plurality of collection heads (321) arranged in a circular array around the axis of the laser channel, so as to achieve comprehensive collection of the signal light.

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