一种针对激光诱导击穿光谱技术的基线校正方法

针对激光诱导击穿光谱(laser-induced breakdown spectroscopy，LIBS)数据中存在的周期性拱形突起问题，提出了一种改进的基线校正算法。该算法基于惩罚最小二乘方法，通过改变局部惩罚系数，使其在拟合周期性拱形突起的同时降低谱线强度对拟合基线的影响。与其他基线校正方法相比，该算法在拟合仿真基线时的均方根误差更小，并且基于该算法得到光谱数据绘制的定标曲线的相关系数达到了0.997 2。结果表明:该算法相较于现有的去基线方法，在拟合中阶梯光栅光谱仪采集激光诱导击穿光谱的基线时，能更好地保留光谱数据的有效信息。

Baseline correction algorithm for laser-induced breakdown spectroscopy

Aiming at the problem of periodic arch protrusion in laser-induced breakdown spectroscopy (LIBS) data, an improved baseline correction algorithm was proposed. By adjusting the local penalty coefficients, the algorithm which was based on penalized least square method could not only fit the periodic arch protrusion, but also reduce the effect of spectral lines intensity on fitting baseline. Compared with other baseline correction methods, the root-mean-square error (RMSE) of the proposed algorithm was smaller when fitting the simulation baseline, and the correlation coefficients of the calibration curve based on spectral data obtained by the proposed algorithm reached 0.997 2. The results show that compared with the existing baseline removal method, the proposed algorithm can better retain the effective information of the spectral data when the echelle grating spectrometer collecting the baseline of LIBS.