What are the names of the ports on a beam splitter

The ports of a beam splitter are called "input" and "output" ports, with each face or side of the splitter serving as a port for light to enter or exit.A beam splitter typically has two or more ports, which are the surfaces through which light enters or exits the device. In a cube beam splitter, each triangular prism face can act as a port, and light incident on one port is partially transmitted and partially reflected to the other ports (faces) of the cube . These are commonly referred to as input ports (where light enters) and output ports (where light exits), regardless of whether the beam splitter is used in transmission or reflection mode . For polarizing beam splitters, the ports are similarly defined, but the exiting beams are distinguished by their polarization states, typically labeled as P-polarized output port and S-polarized output port . In fiber-optic beam splitters, a single input port may feed light into multiple output ports, which distribute the optical signal to different fibers . In summary, the term "port" in the context of a beam splitter refers to any face or interface where light can enter or exit, and they are generally categorized as input and output ports depending on the direction of light propagation.