How does a beam splitter separate the left and right sides

The input beam is spatially separated into two orthogonally polarized beams, diverging at an angle determined by the prism geometry and the material's properties. A beam splitter or beamsplitter is an optical device that splits a beam of light into a transmitted and a reflected beam. It is a crucial part of many optical experimental and measurement systems, such as interferometers, also finding widespread application in fibre optic telecommunications. a laser beam) into two (or sometimes more) beams, which may or may not have the same optical power (radiant flux). This division allows for the simultaneous analysis or utilization of the light's properties along two separate paths. When light enters a beam splitter, it is either reflected or transmitted, according to the optical properties of the beam splitter's material and coating. Free-space beam splitters. [PDF]