PURPOSE: To suppress generation of spurious wave by forming electrodes in parallel with the direction of displacement in a thickness-shear vibrator using a 165±5° rotation Y plate made of lithium niobate.
CONSTITUTION: The electrodes 2, 3 are adhered on a plane in parallel with the direction of vibrating displacement and the lengthwise direction of a piezoelectric raw plate 1 is set to an azimuth of 90±5° to the X axis of the crystal in a strip type piezoelectric vibrator where the electrodes 2, 3 are adhered on both faces of the piezoelectric raw plate 1 using the 165±5° rotation Y plate made of lithium niobate and terminal electrodes 4, 5 are provided at both ends of the lengthwise direction of the piezoelectric raw plate 1. Further, an equivalent series resistance is reduced by setting the relation among plate thickness H, length L and width W of the piezoelectric raw plate 1 as L/H>8, W/H<1.3 or 2.5<W/H<4.3.
FUJIWARA YOSHIAKI
WAKATSUKI NOBORU
KOJIMA YUUJI
| JPS59221023A | 1984-12-12 |
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