Detector Nonlinearity Related Errors in Fourier Transform Spectroscopy and their Correction

Abstract

Due to the relatively high flux levels available in FT-IR spectrophotometers and the universal need for better signal to noise ratios, detectors are often operated in conditions under which their responsivity varies during the measurement. This can happen both during a single measurement (nonlinearity) as well as between measurements (nonequivalence). The results of measurements made under these conditions will contain errors. The quantity and spectral distribution of the errors will depend on both the instrument signature and the sample properties under investigation.