| 摘要 |
PURPOSE:To eliminate the ripple being caused in the pass band and to eliminate the insertion loss by providing an acoustic reflection section formed by short- circuiting adjacent electrode fingers crossed for plural numbers in the same interdigital electrode respectively to interdigital electrode of a reception electrode. CONSTITUTION:Two reception electrodes 7, 8 comprising a couple of interdigital electrodes formed in crossing by positive interdigital electrodes 7a, 8a and negative interdigital electrodes 7b, 8b respectively arranged with a prescribed interval are formed at both sides in the propagation direction of a surface acoustic wave excited from an exciting electrode 6 comprising a couple of interdigital electrodes formed in crossing a positive interdigital electrode 6a and a negative interdigital electrode 6b are formed on a piezoelectric substrate 5. Further, the electrode finger of each interdigital electrode of the reception electrodes 7, 8 is provided with acoustic reflection parts 10, 10...10 provided by forming parts 9, 9...9 short-circuiting the adjacent electrode fingers crossed in the same interdigital electrode and a non-acoustic reflection parts 11, 11...11 not short-circuited.
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