SPECTRAL EMISSIVITY BY INTERFEROMETRIC SPECTROSCOPY

The measurement of infrared spectral emission provides a new and important method for obtaining structural data where ordinary transmission or reflection methods cannot be used. The method involves measuring the spectral emission from a slightly heated sample, where the sample itself is the infrared source. This paper will discuss the utility and important applications of the infrared emission technique in quantitative spectrometric analysis and structure determination as well as the theoretical relationships between emissivity, transmissivity and reflectivity for dielectric films. It will be shown both theoretically and experimentally that undesirable variations in reflectivity are minimized when measuring absorption data by the emission method, rather than by using the transmission technique. A moving-mirror Michelson interferometer spectrometer, which operated between 5 and 45μ, was used for this work. © 1969.