MULTILAYER PIEZOELECTRIC DEVICE

摘要

A multilayer piezoelectric device with excellent reliability and excellent durability is disclosed wherein variations in displacement are small even when the device is used under high-field, high-pressure conditions and changes in the amount of displacement are small even when the device is continuously driven for a long time. The multilayer piezoelectric device comprises a multilayer body composed of piezoelectric layers and internal electrodes alternately stacked upon one another, and external electrodes respectively formed on a first lateral surface and a second lateral surface of the multilayer body. One of every two adjoining internal electrodes is connected to one external electrode on the first lateral surface, while the other internal electrode is connected to the other external electrode on the second lateral surface. In this multilayer piezoelectric device, the rate of change of the displacement amount after continuous driving of not less than 1 x 10<9> times relative to the displacement amount before the continuous driving is within 5%.