A spectrum standardization approach for laser-induced breakdown spectroscopy measurements

Abstract

This paper presents a spectra normalization method for laser-induced breakdown spectroscopy (LIBS) measurements by converting the recorded characteristic line intensity at varying conditions to the intensity under a standard condition with standard plasma temperature, degree of ionization, and total number density of the interested species to reduce the measurement uncertainty. The characteristic line intensities of the interested species are first converted to the intensity at a fixed temperature and standard degree of ionization but varying total number density for each laser pulse analysis. Under this state, if the influence of the variation of plasma morphology is neglected, the sum of multiple spectral line intensities for the measured element can be regarded proportional to the total number density of the specific element, and the fluctuation of the total number density, or the variation of ablation mass, was compensated for by the application of this relationship. In the experiments with 29 brass alloy samples, the application of this method to determine Cu concentration shows a significant improvement over generally applied normalization method for measurement precision and accuracy. The average RSD value, average value of the error bar, R 2 , RMSEP, and average value of the maximum relative error were: 5.29%, 0.68%, 0.98, 2.72%, 16.97%, respectively, while the above parameter values for normalization with the whole spectrum area were: 8.61%, 1.37%, 0.95, 3.28%, 29.19%, respectively.

Calibration Methods of Laser-Induced Breakdown Spectroscopy

“…The final results show the superiority of internal normalization technique over normalization with total light and normalization with background techniques irrespective of whether it is Cr, Ni or Mn analysis. Wang et al presented three spectrum standardized methods in order to improve the reproducibility of LIBS measurements which are named the spectrum standardization approach [30], the sampled spectrum standardization approach [31] and the multivariate spectrum standardization method, respectively. In spectral standardization, a particular example is the use of acoustic signals [32,33] or laser-induced plasma image [34].…”

Wavelet denoising method for laser-induced breakdown spectroscopy

“…[4][5][6] LIBS signal under optimum detection gating conditions and lasers energy can be used to enhance SNR.…”

A Method for Resolving Overlapped Peaks in Laser-Induced Breakdown Spectroscopy (LIBS)

“…[1][2][3][4] Peak overlapping commonly occurs in LIBS data. Although improving the performance of experimental equipment should reduce the interference of overlapped peaks, the high price for hardware with limited resolving effect may be unsatisfactory.…”