This sensor is composed of an infrared emitter on one upright and a
shielded infrared detector on the other. By emitting a beam of infrared
light from one upright to the other, the sensor can detect when an
object passes between the uprights, breaking the beam. Used for many
applications including optical limit switches, pellet dispensing,
general object detection, etc. Gap width = 10mm
A breakout board is available.