Michelson-Type Fourier Spectrometer for the Far Infrared

Abstract

This paper describes the construction, performance, and applications of a Michelson-type Fourier spectrometer designed for spectroscopy in the 10-cm⁻¹ to 200-cm⁻¹ spectral region. Development of the arc-stabilized mercury lamp, adequate stabilization of the cooled detector, and selection of optimum sampling time have provided reproducible and high S/N interferograms. The evaluated reproducibility and accuracy of intensity of the spectrometer are better than :±2%. An apodized resolution of 0.1 cm⁻¹ and accuracy of frequency within 0.015 cm⁻¹ have also been obtained. The electron spin resonance of some biological substances and the refractive index of solids, for example, have been measured with this spectrometer.