Beamsplitters are used either to seperate one single beam into 2 beams which are 90° apart or to combine 2 individual rays of light (with precise positioning) into one. Those that split beams equally into halve-halve are known as a 50/50 beamsplitter. Other split ratios such as 30/70 and 10/90 are also commerically available.

Most beamsplitters come in polarizing and non-polarizing type. Also available are broadband spectral and specific laser beamsplitter.