To reduce loss of light due to absorption by the reflective coating, so-called "Swiss-cheese" beam-splitter mirrors have been used. 📦 For purchasing, use the RP Photonics Buyer's Guide for beam splitters. It provides an expert-curated supplier directory, buyer-focused technical background information, and structured selection criteria to support professional procurement decisions. When a beam splitter divides the incoming light. Beamsplitters are optical components used to split incident light at a designated ratio into two separate beams. It is a crucial part of many optical experimental and measurement systems, such as interferometers, also finding widespread application in fibre optic telecommunications. A lossless device implies that the transformation matrix B is unitary, which.