激光诱导击穿空气等离子体光谱及半经验理论模拟

Spectroscopic Study of Laser Induced Breakdown Plasma Spectroscopy in Air and Semi-Empirical Simulation

利用Nd∶YAG激光器输出的1 064nm激光进行了激光诱导击穿空气光谱实验,测量了空气等离子体的时间分辨光谱。基于局域热动力学平衡模型,建立了模拟激光诱导击穿光谱的方法。对700~900nm波段的空气等离子体光谱进行了模拟。通过模拟结果与实验结果的比较,进一步估算出了空气中氮、氧和氩的相对含量。

A laser induced breakdown spectroscopy experiment was carried out using Nd∶YAG laser in air,and time-resolved spectra were measured.Based on local thermodynamic equilibrium assumption,a method used to simulate LIBS spectra is proposed.A LIBS spectrum of air in the wavelength range of 700~900nm was simulated using this method.A good agreement between experiment and simulation was obtained,and moreover,the relative concentrations of the N,O and Ar in air were obtained.