PIEZOELECTRIC SENSOR

摘要

Disclosed is a piezoelectric sensor wherein variation in the sensitivity is prevented over a wide temperature range. Specifically disclosed is a piezoelectric sensor comprising a piezoelectric device wherein a pair of electrodes are formed on a surface of a piezoelectric ceramic body, and a holding member for holding the piezoelectric device. The piezoelectric ceramic body satisfies the following condition (a) and/or condition (b). (a) The thermal expansion coefficient is not less than 3.0 ppm/°C within a temperature range from -30°C to 160°C. (b) The pyroelectric coefficient is not more than 400 ?Cm