Complex sentence: Makes use of an infrared emitter and receiver to detect the presence of a ball based on whether or not a ball in the feed tube blocks a beam from reaching a receiver on the opposite side.
Split into simpler sentences: Makes use of an infrared emitter and receiver to detect the presence of a ball. Detects whether a ball is present based on whether or not a ball in the feed tube blocks a beam from reaching a receiver on the opposite side.