PURPOSE: To provide a small-sized ultrasonic actuator and a small-sized pyroelectric infrared sensor of improved sensitivity.
CONSTITUTION: Piezoelectric elements 12a, 12b are adhered to two perpendicular surfaces of a regular quadrangular prismlike elastic element 11 to constitute a vibrator 10. When alternating electric fields having a phase difference are applied to the elements 12a, 12b, the vibrator 10 is rotatably moved. Two moving elements 14a, 14b are supported movably only in a direction perpendicular to a longitudinal direction of the vibrator 10 by moving element supports 16a, 16b, brought into pressure contact with the vibrator 10, and reciprocated reversely to one another as rotatably moved. Slits 15a, 15b are respectively formed at the elements 14a, 14b, and an infrared ray 19 is repeatedly incident on and shut OFF from an infrared detector 18 due to superposition and positional deviation of both the slits 15a, 15b as both the elements 14a, 14b are reversely moved.
NOMURA KOJI
NISHIKURA TAKAHIRO
KAWASAKI OSAMU
