Splitter does not generate power nor require power. Hence, it is a passive device. A fiber optic splitter is a passive optical device that can split an incident light beam into two or more light beams (or) it combines two or more light beams into a single light beam. Then, smaller pipes split that. bulk beam splitter consists of a substrate coated with a dielectric film which partially re ects and partially transmits an incident beam. The benefit of this type of coating is that it has low absorption, typically 0. 5 percent for a 50/50 splitter at 45°.