A combination of nano- and microsecond pulses has been suggested for LIBS elemental profiling beyond 1 mm depth for metal coatings. Deep laser ablation and LIBS measurements have been compared for different laser pulse temporal shapes: single and double nanosecond pulses, free-run pulse and combined micro-nanosecond pulse. The deepest laser crater was produced by free-run pulse but plasma emissivity fell dramatically within the first few laser shots. Both single nanosecond pulse and double nanosecond pulse ablation provided crater with depth less than 0.6 mm which is not enough for a typical cladded coating thickness measurements. Nano- and microsecond laser pulses coupling resulted in deep crater formation (> 1.5 mm) but LIBS spectra with good signal-to-noise ratio can be still captured. The feasibility of LIBS depth profiling by coupled nano- (first) and microsecond (second) pulses has been demonstrated for 0.8–1.2 mm thick superalloy coatings measurements.

对于金属涂层，LIBS元素轮廓分析建议使用纳秒和微秒脉冲的组合，深度超过1 mm。对于不同的激光脉冲时间形状，已经比较了深激光烧蚀和LIBS测量：单纳秒和双纳秒脉冲，自由运行脉冲和微纳秒组合脉冲。最深的激光陨石坑是由自由脉冲产生的，但是在前几次激光发射中，等离子体的发射率急剧下降。单纳秒脉冲和双纳秒脉冲烧蚀都提供了深度小于0.6毫米的弹坑，这不足以进行典型的覆层涂层厚度测量。纳秒级和微秒级的激光脉冲耦合导致形成深坑（> 1.5毫米），但仍可以捕获具有良好信噪比的LIBS光谱。