LIBS analysis method based on optical tomography simultaneous iterative reconstruction

Abstract

The invention discloses a LIBS (laser-induced breakdown spectroscopy) analysis method based on optical tomography simultaneous iterative reconstruction. The problem of quantitative solution of multivariate LIBS is a high-precision optical tomography reconstruction problem, and the solution of an incidence matrix F is reconstructed three-dimensional physical quantity distribution in the optical tomography. The method comprises the following steps: a high-precision SIRT iterative algorithm is combined with matrix column vector decomposition to solve all column vectors of the incidence matrix F by column-by-column iteration in order to obtain the incidence matrix F; and the high-precision solution analysis of each element in an unknown sample is realized according to the operation of the actually measured normalized spectral intensity vector and the incidence matrix of the unknown sample. A like optical tomographic model and solving are adopted in the multivariate analysis calibration tosolve the influences of the competitive emission of different elements in the chemical matrix effect; and solving using the SIRT tomographic algorithm effectively inhibits noises in measurement data and obtain the incidence matrix of a minimum root mean square error, so the quantitative analysis precision of LIBS is improved.

Description

technical field [0001] The invention relates to a laser spectrum detection method, in particular to a quantitative laser-induced breakdown spectrum analysis method, which is suitable for simultaneously quantitatively solving and analyzing multiple elements of a detection target, and belongs to the field of photoelectric detection. Background technique [0002] Laser-induced breakdown spectroscopy (LIBS for short) is an atomic analysis spectroscopy technique. It uses nanosecond-level short-pulse laser to focus on the target surface, and the instantaneous high temperature causes the target to be denuded to generate plasma. During the cooling process, atoms and ions fall back from a high-energy state to a low-energy state and emit spectral lines containing element information, which can be used to analyze the constituent elements of materials. probing. LIBS technology can achieve qualitative analysis of target elements well, but quantitative analysis will be affected by chemic...

AI Technical Summary

Problems solved by technology

The advantage of this method is that it can eliminate the influence of chemical matrix effects on the accuracy of quantitative analysis to a certain extent. The disadvantage is that the accuracy of the solution algorithm depends on the previous multi-element calibration mathematical model and the design of the solution algorithm.

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