| abstract |
A piezoelectric actuator 1 includes a piezoelectric element 2 , which has a pair of electrodes formed on the surface of a piezoelectric ceramic member, as a drive source. The piezoelectric actuator 1 satisfies at least one of the following requirements (a) to (c):n (a) the variation width W C in an apparent dynamic capacity C [F] due to a change in temperature should fall within ±11% over a specific temperature range from −30° C. to 80° C.; (b) the variation width W L in a displacement L [μm] due to a change in temperature should fall within ±14% over the specific temperature range from −30° C. to 80° C.; and (c) the variation width W L/C in a quotient L/C due to a change in temperature should fall within ±12% over the specific temperature range from −30° C. to 80° C., wherein C [F] denotes the apparent dynamic capacity and L [μm] denotes the displacement. |