Adafruit ir break beam sensor 5mm leds adafruit 2168 p the adafruit ir break beam sensor is a two part sensor consisting of an infra red emitter and a separate infra red receiver which react when an object interrupts the beam between them they are faster and more targeted than pir sensors and less expensive than sonar sensors these are the 5mm version with a range of up to 500mm you can power them from 3 3 to 5v dc but you will get a more powerful ir beam at 5v the receiver is open co