Piezoelectric vibrator ladder-type filter using piezoeletric vibrator and double-mode piezolectric filter
US6992424B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 7, 2002 |
| Grant date | Jan 31, 2006 |
| Priority date | — |
| Expiry date | Feb 7, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/581
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A piezoelectric vibrator which uses lithium tantalate as a piezoelectric material and of which main vibration is thickness shear vibration. The thickness direction of the vibrator forms angle of 0°±5° to the X-axis of a single crystal. The longitudinal direction of vibrator lies, with the X-axis used as a rotation axis, in direction n +57°±2° clockwise from the Y-axis of the single crystal. A ratio L/H of the length L of the vibrator to the thickness H is not less than 15. A ratio Le/H of the length Le of the exciting electrode to the thickness H of the vibrator element portion is 3–6. Accordingly, a vibrator having improved temperature characteristics and a large Q is realized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.