Patent ID: 7345406

Claim:
A piezoelectric/electrostrictive device comprising: a base being constructed with one sheet of flat plate, the base having a fixing part of a flat plate shape, a mounting part that is separate from the fixing part and having a flat plate shape, and a pair of left and right movable parts, the pair of movable parts each being supported at one end side thereof by each side edge of the fixing part and at the other end side thereof by each side edge of the mounting part, the respective movable parts being erect by a predetermined height from the side edges of the fixing part and the mounting part to face each other and extend along the side edges of the fixing part and the mounting part; and a piezoelectric/electrostrictive element arranged on an inner side of at least one of the pair of left and right movable parts, a first end of the piezoelectric/electrostrictive element extending to a position on the inner side of the at least one of the pair of left and right movable parts, the position overlapping the side edge of the fixing part, wherein (i) La is a distance measured along a respective movable part between a boundary of the respective movable part and the fixing part and a boundary of the respective movable part and the mounting part, (ii) Lb is a distance measured along the respective movable part between the boundary of the respective movable part and the mounting part to a second end of the piezoelectric/electrostrictive element opposite the first end, and (iii) a value of the equation (1−Lb/La) is from 0.5 to 0.8.