Abstract: Based on the power transmission and the properties of Butterworth filter, it achieves a class of FP filters with Butterworth filtering for multi-mirror FP filter. It constructs a mathematical model of several cavities FP filter to implement the Butterworth filtering, and attains their critical conditions. Further more, this paper foresees the mathematical relationships of parameters of mirrors in condition of more cavities, so simplifies the design of multi-cavity FP filters with high performance, and presents a practical method and solutions to design a FP filter with more cavities.

Key words: fabary perot filter, Butterworth filter, transmission