Stability of Rapid Scanning Interferometers

An investigation is made to measure errors and instabilities associated with interferometric spectrometers. All data analysis is performed using the time or distance domain signal (interferogram) to eliminate any anomalies produced by transformation to spectral data. Three basic tests were performed which involved variations of the centerburst amplitude, the interferogram sampling offset and signal stability. These tests were performed on raw data and after all nonzero phase had been removed from the interferometric signal. All errors measured are extremely small, but are larger than ideal detector-limited noise. This paper does not attempt to identify all potential instabilities associated with interferometers, but presents methods by which instabilities can be measured and quantified on a relative basis.