Rapid and high-resolution visualization elements analysis of material surface based on laser-induced breakdown spectroscopy and hyperspectral imaging

Abstract

It is extremely important for material analysis to visualize the elemental distribution of the sample surface quickly, sensibly, and high-resolution. Most point-to-point methods, such as laser-induced breakdown spectroscopy (LIBS), are incapable of achieving high spatial resolution at a reasonable time cost, while surface scanning methods such as hyperspectral imaging (HSI) is insensitive to concentration and material composition. In this work, we proposed a method coupling LIBS with HSI for rapid and high-resolution elemental distribution analysis of material surface. The method of point-to-point laser ablation and region of interest (ROI) segmentation were primarily employed. We further processed the LIBS and HSI spectra and distinguished different ROIs of material surface using principal component analysis. Significant LIBS and HSI lines that contributed to the classification of ROIs were also identified. Moreover, we examined the relationship between the principal component scores of LIBS and HSI spectra based on the Spearman correlation coefficient. Finally, the element visualization images of LIBS and LIBS-HSI were presented and compared. Compared with LIBS imaging, LIBS-HSI imaging offers a better spatial resolution that is at least 90.75 folds higher and a scanning time that is at least 6 times shorter. These results, together with the experimental process, indicate that LIBS-HSI appears to be a promising contender for rapid and high-resolution visual element analysis of material surface.