A distance sensor is a device designed to measure the distance between the sensor and an object without physical contact. It determines the position of an object by emitting a signal—such as sound, light, or electromagnetic waves—and measuring the time or change in the signal when it reflects back from the target. The measured distance is then converted into an electrical or digital output for monitoring, control, or automation purposes.

Distance sensors operate using a variety of technologies depending on the application and required accuracy. Common methods include ultrasonic, infrared (IR), laser (LiDAR), time-of-flight (ToF), capacitive, and radar-based sensing. Each technology provides different range capabilities, accuracy levels, and performance characteristics, making distance sensors suitable for both short-range and long-range measurements across diverse environments.

Modern distance sensors are compact, energy-efficient, and capable of real-time data transmission, allowing seamless integration with IoT platforms, automation systems, and smart monitoring networks.

Distance sensors are widely used in industrial automation, robotics, smart vehicles, smart buildings, level measurement, and security applications, where precise distance measurement is essential for safety, efficiency, and accurate system control.