Optical testing and annealing of the leukosapphire microwave resonators

Waveguide-dielectric resonators (WDR) with partial E-and H-plane filling of the waveguide are investigated by optical and microwave means. Some correlation between the microwave and optical properties of high unloaded Q (Q/sub 0//spl ap/2/spl times/10/sup 4/) resonators is found. The optimal regimes of annealing and the resonant frequency temperature drift reduction, are determined. Some examples of the band-pass filter design are presented.