激光能量及重复频率对土壤等离子体特性的影响  

Influence of Laser Energy and Repetition Rate on Characteristic of Laser-Induced Soil Plasmas

作　　者：鲁翠萍 刘文清(指导)[1] 赵南京 刘立拓 陈东[1] 张玉钧[1] 刘建国[1] 

机构地区：[1]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,安徽省环境光学监测技术重点实验室,安徽合肥230031

出　　处：《中国激光》2011年第2期249-252,共4页Chinese Journal of Lasers

基　　金：国家自然科学基金(60908018);中国科学院知识创新工程重大项目(kzcx1-yw-06-01);安徽省科技计划项目(083H3b1581);所长基金(073H371141)资助课题

摘　　要：利用波长为1064 nm的Nd∶YAG脉冲激光器作光源,以高分辨率、宽光谱段的中阶梯光栅光谱仪和增强型电荷耦合器件（ICCD）作为谱线分离与探测器件,测量并分析了激光能量及重复频率对土壤中铅元素激光诱导击穿光谱特性的影响。实验结果表明,随着激光脉冲能量（在25~105 mJ范围内）增加,谱线强度呈线性增加,随后谱线强度随脉冲能量（105~165 mJ）的变化呈非线性关系。信背比随激光能量的增加而增大,但激光能量超过60 mJ后基本上不变。激光重复频率为1 Hz时,谱线强度最大,而谱线强度的相对标准偏差则在重复频率为7 Hz时最小。The influence of the pulse energy and the pulse repetition frequency are measured.The Nd：YAG pulse laser which wavelength is 1064 nm is used as the excitation source.The characteristics of laser-induced breakdown spectroscopy（LIBS） of metal element Pb in soil are analyzed.The high resolved and the wide spectral echelle spectrograph and intensity charged coupled device（ICCD） are used as the spectral line separation and detector.The experimental results showed that the spectral line intensity increases linearly with the laser energy from 25 to 105 mJ and increases nonlinearly with laser energy from 105 to 165 mJ.The signal to background ratio increases with the pulse laser energy until the laser ernergy is over 60 mJ,then the signal to background ratio is saturated and unchanged with increment of the pulse energy.In the experiment the maximum of spectral intensity is obtained at the repetition rate of 1 Hz.The minimum relative standard deviation is at 7 Hz.

关 键 词：光谱学 激光诱导击穿光谱 激光能量 重复频率 

分 类 号：TN249[电子电信—物理电子学] O433.4[机械工程—光学工程]