| 摘要 |
PURPOSE:To minimize the size of the titled filter by utilizing higher order width vibrations. CONSTITUTION:Prescribed electrodes are installed to one face of a piezo-electric porcelain strip 10 which is polarized in the direction of width in the case of width-length vibration and in the direction of length in the case of side slipping vibration. When the second mode is to be utilized, to suppress the third and forth modes, the center of the gap (g1) between the electrodes 11 and 12 is brought to a location where the stress of the third mode becomes 0 (zero), as shown in (a). Moreover, when the gap between the electrodes 12 and 13 is represented as (g2) and that between the electrodes 13 and 14 is represented as (g3), centers of the gaps (g2) and (g3) are brought to locations where the stress of the forth mode is 0 (zero). In the same way, when the third mode is to be utilized, the second, forth and fifth modes are suppressed by arranging the electrodes as shown in (b). Moreover, when the forth mode is to be utilized, the third, fifth and sixth modes are suppressed, by arranging the electrodes as shown in (c). |
