This paper reviews the on-chip beam splitting methods in recent years, which are mainly divided into the following categories: y-branch, multimode interference coupling, directional coupling, and inverse design. Thorlabs offers a wide range of optical beamsplitters. It is widely used in power splitting, polarization separation, wavelength division multiplexing and. Beamsplitters are optical components used to split input light into two separate parts. It is a crucial part of many optical experimental and measurement systems, such as interferometers, also finding widespread application in fibre optic telecommunications. A polarizing beamsplitter is a type of beamsplitter that splits unpolarized light into S- and P- Polarization states. a laser beam) into two (or sometimes more) beams, which may or may not have the same optical power (radiant flux).