| 摘要 |
PROBLEM TO BE SOLVED: To provide a piezoelectric vibration piece having mesa digging quantity for displaying especially significant effect to reduction of a CI value and suppression of coupling of unnecessary modes.SOLUTION: A piezoelectric vibration piece is a mesa-type piezoelectric vibration piece 10 where a vibrating portion 14, having thickness size larger than that of a peripheral portion 16, is forms on a plate surface of a piezoelectric substrate 12 using thickness-shear vibration as main vibration. A digging quantity y of a step portion is determined so as to satisfy an expression shown using plate thickness t as reference, when size of a major side of the piezoelectric substrate 12 is x, and the thickness size of the piezoelectric substrate 12 in the vibration portion 14 is t. |
