SENSOR ELEMENT AND ANGULAR VELOCITY SENSOR

A piezoelectric body of a sensor includes a driving arm and detecting arm which extend from a base part in a y-axis direction. Excitation electrodes vibrate the driving arm in an x-axis direction. Detecting electrodes enable detection of a signal due to deformation in a z-axis direction of the detecting arm. The piezoelectric body has anisotropy causing vibration of torsional deformation when the driving arm vibrates in the x-axis direction. When the driving arm bends to a +x side, the base part flexes so that a connection position in the base part is displaced to one side in the z-axis direction. The cross-section of the driving arm perpendicular to the y-axis direction causes a bending stiffness to the +x side and to the other side in the z-axis direction is smaller than a bending stiffness to the +x side and to the one side in the z-axis direction.