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  1. M18-Cube: The space saving ifm housing
  2. Technology ultrasonic sensors

Technology overview

Ultrasonic sensors detect all sound-reflecting objects and measures the time from transmission to reception of a sound signal. The target’s color, transparency and surface reflectivity are irrelevant.

Comparison of ultrasonic sensors with other position sensing products

This chart rates the performance of various technologies with certain influences.

  Ultrasonic Inductive Capacitive Photoelectric
Great distance to the object 1
Independent of colour / transparency 11
Independent of material
Temperature fluctuations
Deposits on the sensor 2 3
Extraneous light immunity
High ambient humidity


1) e.g. thin, clear-transparent film/glass
2) if not excessive
3) if non-conductive

Ultrasonic sensors

Ultrasonic sensors are based on the time-of-flight principle. The sensors calculate the time between sending and receiving a reflected sound signal. One advantage of this type of distance measurement is that the measurement result is unaffected by the material properties of the detected target. Even with shiny, coloured or textured surfaces or optically transparent objects, reliable detection is guaranteed.