| 摘要 |
PURPOSE:To obtain a surface acoustic wave resonator with small size, low cost and high reliability by making the thickness of a transducer thinner than the thickness of a reflector so as to attain high resonance sharpness and small resonance resistance. CONSTITUTION:The transducer 2 where a couple of upper and lower comb-line electrodes are formed whose comb-line parts are crossed by a prescribed length and reflectors 3, 4 comprising reed screen electrodes at both sides are provided on a piezoelectric substrate 1. Then the thickness of the transducer 2 is made thinner than the thickness of the reflectors 3, 4, thus the reflectors 3, 4 have additive mass substantially and the reflecting coefficient of the surface acoustic wave resonator is increased remarkably. In connecting said transducer 2 to an external electric circuit and applying an electric signal thereto, the transducer 2 excites a surface acoustic wave in response to the signal and the excited surface acoustic wave is reciprocated between the reflectors 3, 4 so as to be resonated to a prescribed frequency and the resonance is led to the external electric circuit via the transducer 2 again so as to obtain the function of the surface acoustic wave resonator.
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