Fiber optic splitter, also referred to as optical splitter, fiber splitter or beam splitter, is an integrated waveguide optical power distribution device that can split an incident light beam into two or more light beams, and vice versa, containing multiple input and output ends. Additionally, beamsplitters can be used in reverse to combine two different beams into a single one. a laser beam) into two (or sometimes more) beams, which may or may not have the same optical power (radiant flux). It is a crucial part of many optical experimental and measurement systems, such as interferometers, also finding widespread application in fibre optic telecommunications. This is usually done by applying a thin-film coating on a glass substrate and angling the element relative to the incoming light.