Effects of non-uniform distribution of motion on determinations of piezoelectric coupling and constants using IEEE 176-1987

The critical frequencies of practical plate resonators are not determined by the intrinsic or “theoretical” values of mass loading and piezoelectric coupling, but by “effective” values owing to the nonuniform distribution of vibratory motion across the plate. The non-uniform distribution of motion effects are not accounted for in the IEEE 176-1987 recommended thin plate measurement methods for determining piezoelectric coupling and constants. Further, the calculations required to correct measured data for the non-uniform distribution of motion effects are non-trivial. Consequently, a measurement approach in which the distribution of motion plays no part has been developed