| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a vibration piece suppressing a secondary mode. <P>SOLUTION: A vibration piece 10 includes a base part 11, vibration arms 12 and 13 extended from a proximal end part 11a of the base part 11, groove parts 21a and 22a formed on first main surfaces 12a and 13a of the vibration arms 12 and 13, groove parts 21b and 22b formed on second main surfaces, and excitation electrodes 30, 31, 40 and 41 provided on inner wall surfaces of the respective groove parts, and a ratio Lb/La of a length Lb from the proximal end part 11a of the respective excitation electrodes to a length La from the proximal end part 11a of the vibration arms 12 and 13 is set in the range of 0.38≤Lb/La≤0.42. In such a manner, equivalent series capacitance C2 of the secondary mode is turned to 1% or less to equivalent series capacitance C1 of a primary mode, and by improving impedance of the secondary mode and suppressing an electromechanical coupling coefficient K<SP POS="POST">2</SP>low, excitation of the secondary mode is almost eliminated. <P>COPYRIGHT: (C)2013,JPO&INPIT |
