Patent ID: 7567021

Claim:
A piezoelectric/electrostrictive device comprising a monomorph piezoelectric/electrostrictive crystalline body, wherein (i) said piezoelectric/electrostrictive body is lead-free and contains at least Nb, Ta, and one or more types of alkali metal element, ( ii) said piezoelectric/electrostrictive crystalline body has a cubic crystal structure at a temperature higher than a phase transition point and at least any one of tetragonal and orthorhombic crystal structures at a temperature lower than the phase transition point, and (iii) said piezoelectric/electrostrictive crystalline body has a curved shape having a degree of curving larger than that before a polarization treatment at a room temperature lower than the phase transition point, when the piezoelectric/electrostrictive crystalline body is subjected to the polarization treatment.