Lithium niobate piezoelectric transducer - using two metal blocks attached to electrodes, previously heat treated to compensate for resonant frequency temp. coefft.

摘要

Piezoelectric transducer for a mechanical filter comprises a plate of LiNbO3 with two electrodes, e.g. of fired silver paste attached to it and two metal blocks are attached to the eelctrodes. After attachment of the blocks they are heat treated at a temp. high enough to annul the effect of the temp. coefft. of resonant frequency of the transducer. The LiNbO3 does not have to be repolarised after attachment of the blocks by e.g. soldering, unlike prior art materials since its Curic point is about 1200 degrees C.