| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to obtain the favorable piezoelectric characteristics of a piezoelectric element in a wide temperature range by a method wherein in a piezoelectric material provided with more than two electrodes, the two electrodes subjected to polarization treatment are short-circuited using a resistor. SOLUTION: In the case where a piezoelectric element, which consists of a piezoelectric material 4 and is a ferroelectric perovskite-type oxide element 1, is used in a film thickness of 100 μm, a voltage of 100 to 400 V is applied to the element to polarize the element, but when the temperature of this element is abruptly changed from -40 deg.C to 100 deg.C, a high change is generated in the element and a voltage of several 100 V is easily applied to the element itself. At this time, a lot of time is required for discharge, a voltage equal with that at the time of the polarization of the element is applied to the element for a long time and a depolarization of the element is simply caused through. Owing to this, electrodes 2 of the element is short-circuited using a resistor. Thereby, the charge generated by heat is always discharged and as the application of the voltage to the element, which is attributed the piezoelectric characteristics of the element to the main cause, is not caused at all, the characteristics of the element are also not deteriorated. |
