A spatially resolved laser-induced breakdown spectroscopy analysis system and its analysis method

Abstract

The utility model discloses a spatial discrimination laser-induced breakdown spectroscopy analysis system which comprises a pulse laser, a laser beam conversion focus optical system, a displacement platform, a laser-induced plasma signal acquisition device, a spectrometer and a computer, wherein the laser-induced plasma signal acquisition device comprises a clamp and a optical fiber probe; at least one sliding block is arranged on an arched guide track of the clamp; the sliding block can slide on the arched guide track; a sleeve which can move in the radial direction of the arched guide track is arranged in a hole in the center of the sliding block; the optical fiber probe is fixed in the round hole of the sleeve. The analysis system is simple in structure and is capable of acquiring spectral signals of laser-induced plasma in multiple angles and multiple distances, by adjusting the angle and the distance of the optical fiber probe, the continuous spectral background can be inhibited, the device of an LIBS technology is greatly simplified, no time-delay device or positioning device is needed, and the properties of the prior art are improved and expanded.

Description

technical field [0001] The invention relates to a spatially resolved laser-induced breakdown spectrum analysis technology, in particular to a laser-induced plasma signal acquisition device capable of realizing multi-angle and multi-distance adjustment in space and a multi-angle and multi-distance spatially resolved laser-induced breakdown spectrum analysis based on the device systems and their analysis methods. Background technique [0002] Laser Induced Breakdown Spectroscopy (LIBS) is an emerging atomic emission spectrometry technique in recent years. Because this technique does not require complex sample pretreatment, the analysis speed is fast, multiple elements can be analyzed simultaneously, online real-time analysis, micro-area It has many advantages such as remote analysis and remote analysis, and can analyze the composition of solid, liquid and gas samples in extreme external environments, so this technology has been given great attention in recent years. [0003] ...

AI Technical Summary

Problems solved by technology

[0004]However, there are certain limitations in the above-mentioned traditional technology: the time-resolved LIBS technology requires a precise delay device and a detector with a shorter exposure time, not only It increases the complexity of the system, and it is necessary to find a suitable delay and exposure time during use, which is inconvenient to use and is not conducive to the miniaturization of the instrument on-site application

At the same time, the existing fixing device of this technology (with simple angle rotation function) is inconvenient to adjust the fiber probe composed of optical fiber and lens, and cannot be adjusted quantitatively accurately, which is not good for enhancing the signal and improving the signal-to-background ratio. It is very difficult to fix multiple fiber optic probes for signal acquisition

Although the space-resolved LIBS technology overcomes the shortcomings of the time-resolved LIBS technology, it requires the receiving probe to be aimed at a certain position of the plasma and only collects the optical signal of the plasma at this position, which requires measures to make the plasma The expansion is larger and farther, such as keeping the plasma in a low-pressure gas environment, which is convenient for the aiming and positioning of the receiving probe, or imaging the plasma and adjusting the receiving probe with a precise and adjustable positioning device, and reducing the receiving probe to collect optical signals Plasma range, these increase the complexity of the system; more importantly, even if measures are taken to make the receiving probe aim at a certain position of the plasma, the plasma light at this position can only be collected at a fixed angle and distance Signal, due to the anisotropy of the plasma interior and the optical signal emitted by the plasma, only the plasma optical signal at a fixed angle and distance is collected, which cannot fully reflect the spatial distribution of the plasma interior and the optical signal emitted by the plasma, and cannot be better To achieve the purpose of reducing the background and improving the signal-to-background ratio, it is impossible to fully understand the diffusion mechanism and dynamic evolution process of the plasma.

In short, both of the above two technologies have complex devices and operations, inconvenient adjustments, and cannot fully achieve the goals of enhancing the signal, reducing the background, and increasing the signal-to-background ratio.

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