Patent ID: 8727506

Claim:
A method of measuring an angular velocity using an angular velocity sensor, the method comprising: a step of preparing the angular velocity sensor, wherein: the angular velocity sensor comprises a substrate having a vibration part, a piezoelectric film bonded to the vibration part, and an electrode group, the electrode group comprises a drive electrode and a sense electrode, the piezoelectric film comprises a piezoelectric layer and first and second electrodes which sandwich the piezoelectric layer therebetween, the first electrode has a (001) orientation, the piezoelectric layer is composed of (1-z)(Na x Bi y )TiO 0.5x+1.5y+2 -zBaTiO 3 having a (001) orientation, x is not less than 0.30 and not more than 0.46, y is not less than 0.51 and not more than 0.62, z is not less than 0.07 and not more than 0.09, and the electrode group comprises one electrode of the first and second electrodes, a step of applying a driving voltage having an applied electric field of not less than 40 kV/cm and not more than 80 kV/cm to the piezoelectric layer through another electrode of the first and second electrodes and the driving electrode to oscillate the vibration part; and a step of measuring, through the another electrode and the sense electrode, a deformation of the vibration part caused by an angular velocity applied to the oscillating vibration part to obtain a value of the applied angular velocity.