激光诱导击穿光谱最佳探测时间的分析

大气与环境光学学报 ›› 2016, Vol. 11 ›› Issue (5): 383-390.

激光诱导击穿光谱最佳探测时间的分析

余洋, 赵南京*, 方丽, 孟德硕, 谷艳红, 王园园, 贾尧, 马明俊, 刘建国, 刘文清

(中国科学院安徽光学精密机械研究所中国科学院环境光学与技术重点实验室，安徽合肥 230031)

收稿日期:2016-04-27 出版日期:2016-09-28 发布日期:2016-09-19
通讯作者: 赵南京（1976-），男，安徽砀山人，博士，研究员，主要从事激光光谱检测与分析方法等方面的研究。 E-mail:njzhao@aiofm.ac.cn
作者简介:余洋（1988-），男,汉族，湖北黄冈人，博士研究生，主要从事激光诱导击穿光谱应用方面的研究。
基金资助:
Supported by National High Technology Research and Development Program of China(国家863计划,2013AA065502, 2014AA06A513), National Natural Science Foundation of China(国家自然科学基金,61378041）

Analysis on Optimal Detection Time of Laser-Induced Breakdown Spectroscopy

YU Yang, ZHAO Nanjing*, FANG Li, MENG Deshuo, GU Yanhong, WANG Yuanyuan, JIA Yao, MA Mingjun, LIU Jianguo, LIU Wenqing

(Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China)

Received:2016-04-27 Published:2016-09-28 Online:2016-09-19

摘要/Abstract

摘要：

为了确定激光诱导击穿光谱（laser-induced breakdown spectroscopy， LIBS）最佳的探测时间，采用时间分辨LIBS研究了样品中4种元素Fe、Pb、Ca和Mg的4条特征谱线峰值强度以及相应的连续背景辐射光谱强度的衰减特性,对特征谱线峰值强度和连续背景辐射光谱强度的比值求极值，获得了特征谱线最佳信背比（signal-to-background ratio, SBR）所对应时间的计算值。连续背景辐射和特征谱线光谱强度均呈指数形式衰减，4条特征谱线衰减时间分别为1.42, 1.95, 1.69, 1.65 ?s，相应的连续背景辐射衰减时间分别为0.85, 0.93, 0.89, 0.87 ?s。4条特征谱线最佳SBR所对应时间的计算值分别为1.43 ,1.77 ,1.62 ,1.80 ?s，最佳SBR所对应的时间的实验测量值分别为1.5 ,2.0,1.5 ,1.5 ?s，二者具有较好的一致性。特征谱线峰值强度和连续背景辐射光谱强度的演化规律能够对最佳SBR出现的时间作出预测。以上研究结果表明，LIBS最佳探测时间与连续背景辐射和特征谱线的衰减规律密切相关，通过对光谱强度的比值求极值，可以预测谱线最佳SBR出现的时间，此方法为确定LIBS技术探测和分析的最佳时间提供了依据。

关键词: 激光诱导击穿光谱, 特征谱线, 连续背景辐射, 衰减时间, 信背比

Abstract:

In order to determine the optimal detection time of laser induced breakdown spectroscopy(LIBS), time-resolved LIBS technique has been adopted to study the decay characteristics of peak intensity and spectral intensity of four elements Fe, Pb, Ca and Mg contained in the sample. The extreme value of ratio of peak intensity of characteristic lines and spectral intensity of continuous radiation is calculated, and the calculation value of time corresponding to the optimal signal-to-background ratio (SBR) of characteristic lines is obtained. The peak intensity of characteristic lines and spectral intensity of continuous radiation both decay in exponential form, the decay time of four characteristic lines are 1.42, 1.95, 1.69, 1.65 ?s, and the corresponding decay time of continuous radiation are 0.85, 0.93, 0.89, 0.87 ?s respectively. The calculation value of corresponding time of optimal SBR of four characteristic lines are 1.43, 1.77, 1.62, 1.80 ?s, and experimental measurement value of corresponding time of optimal SBR are 1.5, 2.0, 1.5, 1.5 ?s. They have a good consistency. The corresponding time of optimal SBR can be predicted by evolution law of peak intensity of characteristic lines and spectral intensity of continuous radiation. The results indicate that the optimal detection time of LIBS is closely related to decay law of continuous radiation and characteristic lines, and the corresponding time of optimal SBR of spectral lines can be predicted by evaluating extreme value of the ratio of spectral intensity. The method provides the basis for selecting the optimal time of LIBS detection and analysis.

Key words: laser-induced breakdown spectroscopy, characteristic lines, continuous radiation, decay time, signal-to-background ratio

中图分类号:

TN249

余洋赵南京方丽孟德硕谷艳红王园园贾尧马明俊刘建国刘文清. 激光诱导击穿光谱最佳探测时间的分析[J]. 大气与环境光学学报, 2016, 11(5): 383-390.

YU Yang, ZHAO Nan-Jing, FANG Li, MENG De-Shuo, GU Yan-Hong, WANG Yuan-Yuan, JIA Yao, MA MIng-Jun, LIU Jian-Guo, LIU Wen-Qing. Analysis on Optimal Detection Time of Laser-Induced Breakdown Spectroscopy[J]. Journal of Atmospheric and Environmental Optics, 2016, 11(5): 383-390.

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