Electromechanical converter for elastic surface wave

摘要: PURPOSE:To obtain wide fractional band width by composing a two-phase unidirectional converter of two kinds comb line electrodes, differing in number, applied with reference signal and theta deg.-out-of-phase respectively. CONSTITUTION:Piezoelectric substrate 11 is provided common electrode 12, 0 deg.-side 13 signal, 14 deg. out phase the signal. Intersecting finger electrodes are so arranged that while inter-center distances lT lT', both will be an integer greater than wavelength lambda0 elastic wave. In this arrangement, number should differ from 14. As result, loss characteristics greatly improved for various coupling coefficients, can widen, arrangement intersecting set relatively freely. Consequently, sampling errors reduced weighting frequency improvided.