防晒霜作为常见半流体物质，利用激光诱导击穿光谱（LIBS）技术直接烧蚀并检测很难得到较好的效果，为此采用薄膜制样的方法对防晒霜样品进行预处理。探讨了薄膜厚度和基底材料种类对光谱信号的影响，确定了LIBS检测的最优实验条件。在最优条件下检测，经线性拟合计算得到Cd元素的检测限为2.17 μg·g^-1，此检测限已达到了国家规范要求。实验结果证明了LIBS技术可用于防晒霜中重金属元素定量分析，这为化妆品中重金属元素检测提供了依据。

Sunscreen is a common semi-fluid substance, and it is difficult to obtain better results by direct ablation and detection by laser-induced breakdown spectroscopy (LIBS). The effects of film thickness and substrate material types on spectral signals were discussed, and the optimal experimental conditions for LIBS detection were determined. Under optimal conditions, the detection limit of Cd element was calculated by linear fitting to be 2.17 μg·g^-1, which has reached the national standard. The results prove that LIBS technology can be used for the quantitative analysis of heavy metal elements in sunscreen, which provides a basis for the detection of heavy metal elements in cosmetics.