Patent ID: 7639368

Claim:
A method for calculating an interferometric gap of an interferometric sensor from a cross-correlation of the interferometeric sensor and an interferometric correlation element, said method comprising: providing an interferometric sensor having a first gap; providing an interferometric correlation element having a substantially linear varying second gap, said second gap comprising a dispersive material placed in series with said first gap; generating a correlation burst waveform having a plurality of features including peaks and valleys from a cross-correlation of said sensor and said correlation element wherein the shape of the burst waveform evolves due to dispersion across the range of the second gap; collecting data on the correlation burst waveform; tracking said features across an entire range of the first gap and determining a dominant peak or a dominant valley; computing a peak margin, where the peak margin is a ratio of a second largest magnitude peak to the dominant peak subtracted from 100 percent; and using the dominant peak or dominant valley and the computed peak margin to determine a length of the first gap that the dominant peak or dominant valley represents.