A vibrator 10 includes a regular triangular prism-shaped vibrating body 12. On centers of three side faces of the vibrating body 12, piezoelectric elements 14a, 14b and 14c are formed, respectively. Two piezoelectric elements and 14b are used for driving and detecting. The other piezoelectric element 14c is used for feedback. By trimming a ledge-line portion 12a of the vibrating body 12, a resonance frequency on driving side is controlled. By trimming ledge-line portions 12b and 12c of the vibrating body 12, two resonance frequencies on detecting side are controlled.