Patent ID: 7932664

Claim:
A flexural vibration piece comprising: a base portion; and a vibration arm extending from the base portion, wherein the vibration arm has first and second main faces which are arranged to be opposite each other, the first main face have first groove which is formed in the longitudinal direction of the vibration arm, the second main face have second groove which is formed in the longitudinal direction of the vibration arm, the vibration arm further has a longitudinal center line which extends in the longitudinal direction of the vibration arm, the first groove has a plurality of first groove portions which are arranged on both sides with respect to the longitudinal center line, the plurality of first groove portions being shifted from each other in the longitudinal direction of the vibration arm, the second groove has a plurality of second groove portions which are arranged on both sides with respect to the longitudinal center line, the plurality of second groove portions being shifted from each other in the longitudinal direction of the vibration arm and being arranged on an opposite side to the first groove portions with respect to the longitudinal center line.