| 摘要 |
PROBLEM TO BE SOLVED: To obtain means for decreasing types of a crystal wafer, while satisfying frequency stability in a specified temperature range of a crystal vibrator.SOLUTION: A vibration element includes a substrate 10, a pair of front and rear excitation electrodes 20a and 20b. The substrate 10 has a planar base 12, a first protrusion 14 projecting from one face of the substrate 10 to a thickness direction, and a second protrusion 16 projecting from the other face in the thickness direction. The first and second protrusion 14 and 16 are formed asymmetrically to a plane passing a center of the base 12 in the thickness direction, and orthogonal to the thickness direction.SELECTED DRAWING: Figure 1 |
