Semiconductor foil beam-splitter for an infrared spectrometer

摘要

In a self-supporting beam-splitter (1), in particular for use in an FTIR-spectrometer for the far-infrared region, with an optical thickness on the order of the interesting wavelength region, the foil beam-splitter (1) consists of an undoped semi-conducter material or carbon which is transparent in the far-infrared, and is preferentially made from thin silicon sheets or diamond foil in the thickness region between 2 mu m and 125 mu m. In this fashion, an extremely high efficiency for the beam-splitter is achieved, whereby little or no resonant absorption takes place due to the beam-splitter in the interesting wavelength region.