Proximity & Presence Sensor

A proximity sensor (also known as a contactless, non-contact, or sensing sensor) is a device used to detect an object or person, their presence and absence as well as objects or people approaching them; for example, a car is detected as it drives within a specified area without having to be in physical contact with the object or person.

Sensors will identify whether the object or person is close by (proximity), or if the object or person is stationary and occupying space (presence). These sensors then convert this information into electrical or digital signals for monitoring, controlling and/or automating a process.

A proximity sensor is typically a short-range detection device used to identify a nearby object, such as a person or vehicle entering or leaving a defined zone. A presence sensor has a higher detection sensitivity and provides a continuous detection capability; therefore, they can detect stationary or limited movement (such as when a person has been sitting or standing still for an extended period of time) as well as continuous activity. Because of this, they are used in applications requiring precise occupancy awareness.

There are many different sensing technologies used in proximity and presence sensors, including infrared (IR), capacitive, ultrasonic, microwave (Radar), inductive, and optical sensing. Each technology operates best with certain materials, at specific distances, and in specific environmental conditions to provide reliable performance in a wide range of applications.

Modern proximity and presence sensors have been designed to be small, energy-efficient and responsive to ensure they work seamlessly with Internet of Things (IoT) platforms and other automated systems. Additionally, they are found in many types of buildings such as smart buildings; factory automation; building and construction; security systems; lighting control; and energy management.