| 摘要 |
PURPOSE:To generate a constant displacement at all times without controlling a driving electric field strength by using an elastic plate and a material whose phase is transferred from an anti-ferroelectric phase to a ferroelectric phase and whose volume expands simultaneously when an electric field is applied. CONSTITUTION:A metallic electrode film 12 is arranged on the front and back sides of a plate 11 made of anti-ferroelectric ceramics which is expressed by, for example, Pb0.99Nb0.02[(Zr0.6Sn0.4)0.94Ti0.06-]0.98O3 and whose phase is transferred from an anti-ferroelectric phase to a ferroelectric phase and simultaneously whose volume expands. This is bonded to a metallic plate 13 having elastic properties. When an electric field of critical field strength or over is applied in a direction of the thickness of the plate 11, the plate 11 is going to extend vertically to the electric field, but the plate 13 deforms and bends its free end. The quantity of this deformation is not proportional to the field strength and it is kept constant when the strength is the critical field strength or over. Accordingly, a constant displacement can be generated without controlling the electric field strength precisely. |
