就Ｎｄ：ＹＡＧ泵浦的染料激光进行锡原子三步共振电离，求解非饱和共振过程速率方程。计算共振吸收截面，给出电离效率分别与激发速率、电离速率以及作用时间的关系，得出饱和激发电离的流量条件和通量条件。并进行了讨论。 The Nd: YAG-pumped dye laser was used to perform the three-step resonance ionization of tin atom to solve the rate equation of unsaturated resonance. The resonant absorption cross sections were calculated and the relation between the ionization efficiency and the excitation rate, ionization rate and action time were given respectively. The flow conditions and flux conditions of the saturation excitation ionization were obtained. And discussed.