工作参数对激光诱导土壤等离子体光谱特性的影响

大气与环境光学学报 ›› 2016, Vol. 11 ›› Issue (5): 361-366.

工作参数对激光诱导土壤等离子体光谱特性的影响

周卫东, 刘燕杰, 黄基松

(浙江省光信息检测与显示技术研究重点实验室，浙江师范大学, 浙江金华 321004)

收稿日期:2016-05-12 出版日期:2016-09-28 发布日期:2016-09-19
通讯作者: 周卫东（1966-），男，安徽安庆人，研究员，博士生导师，主要从事激光光谱检测、光电离解离和激光技术方面的研究工作。 E-mail:wdzhou@zjnu.cn
作者简介:周卫东（1966-），男，安徽安庆人，研究员，博士生导师，主要从事激光光谱检测、光电离解离和激光技术方面的研究工作。
基金资助:
Supported by National Natural Science Foundation of China(国家自然科学基金, 51276100）, Natural Science Foundation of Zhejiang Province(浙江省自然科学基金, LY14F05003）, National Student Innovation Training and Venture Program(国家大学生创新创业项目, 201510315010）

Effects of Parameters on the Spectrum Character of Laser Induced Soil Plasma

ZHOU Weidong, LIU Yanjie, HUANG Jisong

(Key Laboratory of Optical Information Detection and Display Technology of Zhejiang, Zhejiang Normal University, Jinhua 321004, China)

Received:2016-05-12 Published:2016-09-28 Online:2016-09-19

摘要/Abstract

摘要：

采用波长1064 nm的调Q脉冲Nd:YAG激光器和多通道小型光纤光栅光谱仪，搭建了一套激光诱导击穿光谱分析系统。选择土壤中常见元素AlⅡ(422.68 nm)作为分析线，详细研究激光能量和采样延迟对激光诱导土壤等离子体光谱特性的影响。在相同激光能量下，随着采样延迟时间增加时，信号强度、背景强度、噪声都将变小，而SNR则呈现先增大后减小的趋势；在相同采样延迟时间下，增加激光能量，信号强度、噪声也将增强，而背景强度和信噪比的变化则呈现先增加后减小的趋势。对于某一定的激光能量, 存在一个与之相对应最佳采样延迟时间，随着激光能量增加时，最佳延迟时间也会增大。综合考虑采样延迟时间和激光能量对激光诱导等离子体光谱信噪比的影响，给出了系统的最优化工作参数是激光能量120 mJ、最佳采样延迟时间1.5 μs。

关键词: 激光诱导击穿光谱, 激光能量, 延迟时间, 土壤

Abstract:

A laser induced breakdown spectroscopy analytical system was established by using a pulsed 1064 nm Nd:YAG laser and a portable fiber optical spectrometer. The emitted spectra of the laser induced soil plasma were recorded along with the variation of experimental parameters. By using the AlⅡ 422.68 nm as the analysis line, the effects of the laser energy and data acquisition delay time on the spectrum characterizations of soil plasma emission were investigated in detail. Generally, at a fixed laser energy, the signal intensity, background and noise of the spectrum decrease with a longer acquisition time delay, while the signal to noise ratio (SNR) first increases to a maximum and then decreases. And at a fixed data acquisition time delay, the signal intensity and noise of the spectrum increase with the increase of laser energy, but the background and SNR first increase to a maximum and then decrease. For specific laser energy, the SNR can be optimized at a selected suitable data acquisition time delay, and the optimal time delay will increase with increased laser energy. Based on the combination effects of laser energy and data acquisition time delay, the optimized parameters of the system are 120 mJ for the laser energy and 1.5 μs for the acquisition delay time.

Key words: laser-induced breakdown spectroscopy, laser energy, acquisition delay time, soil

中图分类号:

O433.4

周卫东刘燕杰黄基松. 工作参数对激光诱导土壤等离子体光谱特性的影响[J]. 大气与环境光学学报, 2016, 11(5): 361-366.

ZHOU Wei-Dong, LIU Yan-Jie, HUANG Ji-Song. Effects of Parameters on the Spectrum Character of Laser Induced Soil Plasma[J]. Journal of Atmospheric and Environmental Optics, 2016, 11(5): 361-366.

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