Patent ID: 8405285

Claim:
A piezoelectric device, comprising a piezoelectric body having piezoelectricity and a pair of electrodes for applying an electric field to the piezoelectric body in a predetermined direction, wherein a piezoelectric strain constant d 33 (pm/V) and a relative permittivity ε 33 of the piezoelectric body satisfy Formulae (1) and (2) below 100<ε 33 <1500 (1) d 33 (pm/V)>12√ε 33 (2) wherein the piezoelectric body is formed of one or more types of perovskite oxides represented by General Formula (P) below, (Ba, Bi, A)(Ti, Fe, M)O 3 (P) wherein, in General Formula (P), Ba, Bi, and A are A-site elements and Ti, Fe, and M are B-site elements, each of A and M being one or more types of metal elements other than Pb and AMO 3 in the General Formula (P) excludes BaTiO 3 and BiFeO 3 , wherein the piezoelectric body is a particle oriented ceramics sintered body.