Synchrotrons versus globars, point-detectors versus focal plane arrays: Selecting the best source and detector for specific infrared microspectroscopy and imaging applications

Abstract

Fourier transform infrared microspectroscopy (FTIRM) and imaging (FTIRI) have become valuable techniques for examining the chemical composition of materials on a microscopic scale. Most IR microscopes are equipped with conventional thermal (globar) IR sources and single-element (point) detectors. Recently, the spatial resolution of IR microspectroscopy has been dramatically improved by using synchrotron light as the IR source. Also, the data collection rates of the technique have radically increased through the implementation of one- and two-dimensional focal plane array detectors. The choice of IR source and detector is important, and depends on the particular application. In this work, we show the differences between conventional globar IR sources and synchrotron light, and between a single-point-detector and focal plane array (FPA). These comparisons provide guidance for the preferable IR source and detector based on the type of application.