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为了改善激光诱导击穿光谱质量，本文使用具有时间分辨功能的光谱仪采集激光诱导钢靶等离子体光谱，研究了钢靶等离子体辐射光谱随延迟时间的变化特性。结果表明，光谱强度和背景强度随延时皆呈指数衰减变弱，原子谱线强度在前 4μs 内衰减更快但寿命较长，而离子谱线存在寿命较短；采集延时对不同谱线的信噪比影响不一样，Mn I 403.08nm、Cr I 428.97nm、Cr II 458.82nm、Fe I 430.79nm 和 Fe II 503.57nm 谱线得到的最佳延时分别为 8μs、2μs、0μs、2μs 和 4μs；采用双线法和 Boltzmann plot 方法计算等离子体温度、Saha-Boltzmann 方程计算电子密度，验证了在 0～10μs 范围内采集到的光谱信号满足局部热平衡状态。
In order to improve the quality of laser-induced breakdown spectroscopy, we use the spectrometer with time-resolved function to acquire the laser-induced plasma target plasma spectrum and study the variation characteristics of the laser target plasma with the delay time. The results show that both the spectral intensity and the background intensity decrease exponentially with time delay, the intensity of the atomic line decays faster and lasts longer in the first 4μs, but the lifetime of the ion spectrum is shorter. , Respectively. The best delay times of Mn I 403.08nm, Cr I 428.97nm, Cr II 458.82nm, Fe I 430.79nm and Fe II 503.57nm were 8μs, 2μs, 0μs, 2μs and 4μs. The plasma temperature was calculated by the two-line method and the Boltzmann plot method, and the electron density was calculated by the Saha-Boltzmann equation. It was verified that the spectral signals collected in the range of 0 ~ 10μs satisfied the local thermal equilibrium.