Fork sensors which are also called “Slot sensors” as well as through-beam photoelectric sensors are based on the same basic principle.
These types of photoelectric sensors which are U shaped, combine emitter and receiver in a single housing while the sender emits light beams to the receiver concentratedly.
As soon as the light beam from the sender is interrupted by an object, the switching output will be switched.
Fork sensors are used for detecting small objects or for detecting labels and print marks, even on transparent films.
