| abstract |
A piezoelectric actuator (1) comprising a piezoelectric element (2) having a pair of electrodes formed on the surface of a piezoelectric ceramic as a drive source. The piezoelectric actuator (1) satisfies at least one of following requirements. (a) Variation width WC of apparent dynamic capacitance C (F) due to temperature variation falls within ±11% in a specific temperature range of -30 to 80°C. (b) Variation width WL of displacement L (µm) due to temperature variation falls within ±14% in a specific temperature range of -30 to 80°C. (c) Variation width WL/C of L/C due to temperature variation falls within ±12% in a specific temperature range of -30 to 80°C, assuming that the apparent dynamic capacitance is C (F) and the displacement is L (µm). |