理论上阐述了螺旋相位板产生涡旋光束的机理，推导了涡旋光束与平面波以及球面波的干涉强度表达式，并用以研究了涡旋光束的干涉现象，从数值上得到了拓扑荷数与干涉图样的对应关系。同时在实验上利用螺旋相位板获得了涡旋光束，并得到其干涉图样，实验结果与理论结果保持一致。研究结果表明，携带不同拓扑荷的涡旋光束对应着唯一的干涉图样，因此可以通过干涉图样直观地判断出涡旋光束的拓扑荷数。

The mechanism of vortex beam generated by spiral phase plate is expounded theoretically. The interference intensity expressions of the vortex beams, plane wave and spherical wave are derived and used to study the interference phenomenon of vortex beam. The corresponding relationship between topological charge and interference pattern is obtained numerically. Meanwhile, the vortex beams are obtained by spiral phase plate experimentally, and the corresponding experimental results are presented, as well as the experimental results and numerical results are practically consistent. The results show that vortex beams with different topological charges correspond to uniqueness interference pattern, hence the topological charge of vortex beam can be intuitively detected by the interference pattern.