Adafruit IR Break Beam Sensor - 5mm LEDs

Key Features: Simple way to detect motion Faster than PIR sensors and allow better control of where you want to detect the motion Works up to 20 inches Open collector transistor output receiver Infrared (IR) break-beam sensors are a simple way to detect motion. They work by having an emitter side that sends out a beam of human-invisible IR light, then a receiver across the way which is sensitive to that same light. When something passes between the two, and its not transparent to IR, then the 'beam is broken' and the receiver will let you know.Compared to PIR sensors, breakbeams are faster and allow better control of where you want to detect the motion. Compared to Sonar modules, they're less expensive. However, you do need both emitter and receiver on opposite sides of the area you want to monitor.This is the 5mm IR version.  It works up to 50cm / 20". You can power it from 3.3V or 5V, but 5V will get you better range and is what we suggest. The receiver is open collector transistor o