Ultrasonic alarm

Description

A sensor device use to detect movement in a room. Ultrasonic alarms fill a room with a constant stream of low level ultrasonic vibrations. Any disruption in the vibration wave is picked up by the sensor, which in turn can send an alarm signal. Ultrasonic alarms typically generate a signal with an intensity of 10-11 W/cm2. This is about 1 order of magnitude lower than sounds that can be heard by the human ear and 11 orders of magnitude lower than the intensity of vibrations used for cleaning.

Synonyms and Related Terms

alarme ultrasonore (Fr.);