SILICON COATED MYLAR BEAMSPLITTER

摘要

The invention disclosed relates to a composite material for use in a beamsplitter for the far infrared which provides a high operating efficiency over the spectral range of 50 to 550 cm-1. The composite comprises a thin, substantially uniformly thick synthetic resin film having low far infrared absorption, preferably polyethyleneterephthalate, and a thin substantially uniformly thick coating of a transparent material having an index of refraction of about twice that of the substrate, preferably of geranium. An improved interferometer including a beamsplitter formed of the composite is also disclosed.