How does an ultrasonic sensor work?

Ultrasonic sensors can be used for many different applications. They are most commonly used to measure distance or detect presence. For example, measuring levels of liquids and granules or to check if an object is at the correct distance.

Ultrasonic sensors can calculate distance with high accuracy and over long distances by measuring the time for an echo to return to the sensor. Essentially, they can detect anything that reflects sound. They work equally well regardless of color and even against transparent objects.

Double layers and labels can be detected by measuring the attenuation of sound through the materials.