Spectral Fizeau Interferometer spectra processing by means of a fuzzy inference system

A fiber optic frequency domain Fizeau Interferometer (FFI) is a photonic instrument of extremely high resolution, so it can be used as a micrometric distances sensor. Relevant information is modulated in the spectrum and usually it requires hard efforts for demodulation In this work we present a method for automatic processing of these spectra without user intervention. Interfering cavity length is determined from FFI spectra and also from a time domain Fizeau Interferometer (TFI), both measures obtained over the same sample at once (FFI & TFI). Demodulation procedure utilizes a fuzzy inference system based on subtractive clustering in order to process FFI spectra and hence, the resonant cavity length from spectrometer readings. This method was tested in controlled experiments providing excellent results.