Ultrasonic principle:
Ultrasonic sensors emit short, high-frequency sound pulses at regular intervals. These propagate in the air at the velocity of sound. If they strike an object, then they are reflected back as echo signals to the sensor, which itself computes the distance to the target based on the time-span between emitting the signal and receiving the echo.
US500-GM18
Regardless of color and material
BUS ultrasonic sensors are perfect for distance measurement or
position detection of granules, fluids and powders. They measure fill
levels, heights and sag without making contact as well as count and
monitor the presence of objects.
They are extremely versatile, operate independently of color and surface finish, and are not affected by transparent objects that
generate
strong reflections.
Ultrasonic sensors are precision all-rounders designed for critical
situations. Dust, dirt and steam do not pose a problem.