| 摘要 |
An elastic wave position-sensing device comprising two elastic wave transducing units X and Y, a nonpiezoelectric plate, and a controlling system connected with the units X and Y. Each unit consists of a piezoelectric substrates PT and PR, interdigital transducers T0 and Ti (i=1, 2, . . . , N) formed on one end surface of the piezoelectric substrate PT, interdigital transducers R0, Ri1 and Ri2 (i=1, 2, . . . , N) placed on one end surface of the piezoelectric substrate PR. Each of the interdigital transducers Ri1 and Ri2 is placed such that the finger direction thereof is slanting to that of the interdigital transducer Ti by an angle alpha . The thickness d of the piezoelectric substrates PT and PR is smaller than an interdigital periodicity P of the interdigital transducers T0, Ti and R0. The thickness of the nonpiezoelectric plate is smaller than two times the thickness d, the piezoelectric substrates PT and PR being mounted on one end surface of the nonpiezoelectric plate. A part, adjacent to the piezoelectric substrate PT, of the nonpiezoelectric plate, and the piezoelectric substrate PT form a bilayer zone BT. A part, adjacent to the piezoelectric substrate PR, of the nonpiezoelectric plate, and the piezoelectric substrate PR form a bilayer zone BR. When an electric signal is applied to each of the interdigital transducers T0 and Ti, an elastic wave is excited in the bilayer zone BT, and transmitted to the bilayer zone BR through the monolayer zone between the bilayer zones BT and BR.
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