The methods of coupling between LD and optical fiber can be divided into direct and indirectcoupling according to whether optical devices exist between them.
LD与光纤的耦合，按照LD与光纤之间是否存在光学元件，耦合方式可分为两种，即直接耦合与间接耦合。
2
The direct and indirectcoupling loss factors of a coupled system with three substructures are predicted by using this method, and the measured data agree well with the predicted results.
An indirect inverse substructure scheme for calculating the dynamic stiffness of discrete coupling unit-of-packaging was introduced. A formula was derived based on matrix theory.