POLARISING CUBE BEAM SPLITTERS

A cube polarizer consists of a pair of cemented precision right-angle prisms to form a cube with low output beam distortion. The hypotenuse of one of the prisms is coated with a multilayer dielectric polarizing beamsplitter coating optimized for a specified wavelength range. The four outer faces are antireflection coated with a multilayer dielectric coating to minimize surface reflection losses. An unpolarized beam is split into two orthogonal, linearly polarized components. P-polarized light is transmitted, while s-polarized light is reflected, both with negligible absorption. The extinction ratio is better than 500:1 and is used as a broadband polarizer in a standard cube configuration.