摘要
In the study of the theory of wave propagation, the theory of mode representation and the theory of ray representation have long been used. These two kinds of representation express respectively the two kinds of fields and they are sometimes called the 'mode-ray duality' problem. No rigid relation of transformation exists between the mode and classical ray. The generalized ray method developed recently is a rigid solution for the wave equations. When there are many different descriptions of the same physical reality,
