HELMHOLTZ THEOREM AND EXPANSIONS OF EIGENFUNCTIONS OF ELECTROMAGNETIC FIELD IN RESONANT CAVITY
谐振腔中的亥姆霍兹定理及电磁场的本征函数展开问题

The rational form of Helmholtz theorem in resonant cavity is discussed. On the basis of the theorem, it is proved that the electric irrotational field can be expanded into a convergent series on L vector wave function, and that the electric rotational field also can be expanded into a convergent series on M and N vector wave functions. So it is proved that L,M and N vector wave functions consist of a complete orthogonal basis for electric field in resonant cavity.