摘要 |
In an energy trapping type ceramic filter vibrating in the thickness shear-slide mode, vibrating electrodes are formed on opposite sides of a piezoelectric ceramic substrate, while an input terminal electrode and an output terminal electrode are provided on both end portions of the substrate so that lead terminals are soldered to the terminal electrodes. A distance l5 between the input terminal electrode and the adjacent vibrating electrode and a distance l6 between the output terminal electrode and the adjacent vibrating electrode are set within a range of one to three times the thickness of the substrate. Thus, it is possible to suppress undesired vibration other than principal vibration, thereby improving filter characteristics.
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