为了解释一维掺杂光子晶体缺陷模的产生机理，建立了一维掺杂光子晶体的多波束干涉模型\.利用多光束干涉原理建立了一维掺杂光子晶体缺陷模的干涉理论，成功地解释了一维掺杂光子晶体中缺陷模的产生机理\.应用干涉理论和特征矩阵法对一维掺杂光子晶体缺陷模的特征进行了比较研究，两者的结论是一致的。

In order to explain the reason of the defect mode in one-dimensional (1D) doped cycle photonic crystal, a multiple-beam interference model of 1D doped photonic crystal is established. Interference theory of the defect mode in 1D doped photonic crystal is established by interference theory, and the mechanism of the defect mode of 1D doped photonic crystal is explained. The defect modes are studied by interference theory and characteristic matrix method, and their conclusion are the same.