Calibration and Use of a Cesium-Iodide Prism in the Infrared

Abstract

With a cesium-iodide prism the long wavelength range of an infrared spectrometer may be extended to 55μ The use of such a prism, the choice of optical system, and the problems of stray radiation are all discussed. Accurate data are assembled for calibration in this region, and sample calibration traces are shown. A simple gas absorption cell is described for use at long wavelengths.