How Science Can Help You Open a Locked Door! A passive infrared (PIR) motion sensor is an electronic device that detects motion by sensing changes in infrared radiation, primarily emitted by warm objects like humans and animals. Unlike active sensors, PIR sensors do not emit any signals; instead, they passively detect infrared radiation through two or more pyroelectric elements that generate a voltage when they detect changes in radiation levels. Typically, these sensors have a detection range o

A Passive Infrared (PIR) is an electronic device used to detect motion by measuring infrared (IR) radiation emitted by objects in its field of view. The sensor is made up of two slots, each sensitive to infrared radiation. When a warm object (like a person) enters the field of view, it creates a difference in the infrared levels between the two slots, causing the sensor to trigger. The PIR sensor doesn't detect specific objects but rather changes in infrared levels caused by movement. PIR sensor