Environment difference detection device using a surface acoustic wave element and surface acoustic wave device

摘要

PROBLEM TO BE SOLVED: To provide a surface acoustic wave element which is suitable for mass production and stably exhibits excellent surface acoustic wave propagation performance at all the time and an environmental difference detector using the surface acoustic wave element.;SOLUTION: The surface acoustic wave element is provided with: a three-dimensional substrate 12 having a surface including a part of at least a circular curved surface having a continuous curved surface through which a surface acoustic wave propagates; and an electroacoustic transducer element 14 for exciting a surface acoustic wave on the surface, propagates the surface acoustic wave along the surface, and receives a propagating surface acoustic wave. The three-dimensional substrate is made of LiTaO₃ crystal. On the surface of the three-dimensional substrate, the electroacoustic transducer element propagates the surface acoustic wave along an intersection between crystal faces of the crystal and the surface, where the intersection is a maximal outer circumferential line on the surface. An environmental difference detector compares surface acoustic wave reception signals of the electroacoustic transducer elements of a plurality of propagation surface zones of the surface acoustic wave elements and detects an environmental difference in spatial parts in contact with each of them.;COPYRIGHT: (C)2010,JPO&INPIT