In two-stage splitting applications, the first-stage optical splitter is often installed in an optical distribution box or a fiber-splitting box, while the second-stage optical splitter is often installed in a local residence or community closer to the end-user. Its basic form is "OLT → Optical Splitter → ONU", and the splitting ratio of the optical splitter used here is usually 1:64. Additionally, beamsplitters can be used in reverse to combine two different beams into a single one. How Does a PBS Work? Operating Principle: Light possesses various polarization states, like horizontal or vertical. A PBS generally transmits one state and. The tutorial initializes with a cube beamsplitter positioned with an incident light wave impacting the planar front surface at a 90-degree angle (perpendicular) to the direction of propagation. In order to operate the tutorial, use the mouse cursor to translate the Transmission slider between a. In the application of primary splitter, the optical splitter can be installed in the central office, but in order to save the cost of optical fiber, the optical splitter is usually installed between OLT and ONU.