Interference inhomogeneities of the stacks used in laser cavities

A matrix method is used in calculating the reflection coefficient of the stacks used as the output mirror of a laser cavity. It is shown that the reflection coefficient can vary significantly over the cross section of the stack because of fabrication errors in the elements of the stack. The reflection coefficient of a stack that has been evaluated by such an indirect method cannot be used, for example, in analyzing the processes that determine the radiation density distribution inside and outside the cavity in the same way as in analyzing a number of other phenomena that characterize the lasing process.