Noncontact infrared reflection spectroscopy using optical fibers

Abstract

Silver halide infrared transmitting optical fibers are used in a noncontact mode to deliver and collect infrared radiation from a thin liquid sample on a highly reflecting substrate. The detected signal is a sensitive measure of the absorption spectrum of the liquid under study. Optimal placement of the fibers with respect to the sample was calculated and experimentally confirmed. The system provides a quantitative infrared spectrum with minimal sample preparation.