Safety photocell infrared beams are laser beams installed at the gate to keep your gates open while a vehicle or a person is in their path. These devices are a must for automatic gates and can literally save lives. There are two types of photo-eyes: the first and most common is the reflector-based photocell which is installed on one side where its reflector on the other reducing the need to run wiring to both sides. The second and less common is the dual beam where communication wires are installed between the two sides. The upside to these dual-beam photoeyes is stability - they rarely give out a false read as reflector-based may do during bad weather.