中文摘要：

用Nd：YAG脉冲激光器产生的1．06μm激光，在低压环境下烧蚀金属Al靶获得等离子体．并观测其空间分辨发射光谱；利用AlⅠ的两条发射谱线的Stark展宽计算了Al等离子体电子密度．研究了电子密度随空间的演化规律。结果发现：在靶面附近电子密度达到最大值，随着离靶面距离的增加，电子密度逐渐减小，从微观物理机制的分析推断：激光诱导等离子体的复合辐射是电子密度减少的主要原因。另外，还探讨了激光能量的变化对等离子体电子密度的影响。

英文摘要：

By using 1.06μm pulse laser produced by Nd：YAG laser ablation, the space resolved emission spectra were gotten at low air pressure. The electron density of Nd：YAG laser induced Al plasma were calculated by the measured Stark broadening. The dependence of electron density on the space were studied, it reaches its highest value hear the target surface, and reduces with the distance increasing from target surface. Recombination radiation is considered to be the primary reason of electron density reducing, and in a certain extent the experiment result is to be explained by it. The effects of laser pulse energy on the electron density were also studied in this paper.