Piezoelectric device, piezoelectric actuator having the same, liquid discharge apparatus, and power generating apparatus

摘要

A piezoelectric device which includes a piezoelectric body having piezoelectricity and a pair of electrodes for applying an electric field to the piezoelectric body in a predetermined direction in which a piezoelectric strain constant d33 (pm/V) and a relative pemittivity &egr;33 of the piezoelectric body satisfy Formulae (1) and (2) below. This makes the piezoelectric device excellent both in transmission and reception capabilities and appropriate for use as a piezoelectric actuator, a sensor, an ultrasonic sensor, or a power generating device. 100<&egr;33<1500  (1) d33(pm/V)>12√&egr;33  (2).