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Proximity Sensor

What Does Proximity Sensor Mean?

A proximity sensor is an intelligent sensor that can detect the presence of objects within its vicinity without any actual physical contact. Proximity sensors, which are often used in collision warning and collision avoidance systems, have the ability to detect the presence of a target within a defined range. A proximity sensor might use, sound, light, infrared radiation (IR) or electromagnetic fields to detect a target.


Proximity sensors are commonly used in industrial applications and consumer robotics. They are also used in vehicles for detecting the physical closeness of other vehicles, as well as for parking-assist functions.

Techopedia Explains Proximity Sensor

There are many types of proximity sensors and they use different methods for sensing. For example, capacitive and photoelectric sensors are more suited to plastic and organic targets, whereas inductive proximity sensors can only detect metal targets.

The three most common types of proximity sensors in use today in the industrial internet of things (IIoT) are capacitive, ultrasonic and inductive.

  • Capacitive sensors rely on changes in the electrical field around a sensor.
  • Ultrasonic sensors rely on sound waves that are either reflected or absorbed by objects within the sensing range.
  • Inductive sensors rely on changes in the magnetic field around the sensor.


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