White-light interferometry-Envelope detection by Hilbert transform and influence of noise

► We calculate the autocorrelation of the noise of the calculated envelope in white-light interferometry. ► The autocorrelation function depends on the ratio between the mean wavelength of the used light and the sampling step. ► The correlation of the envelope noise causes that the measurement uncertainty of white-light interferometry. ► By factor square root of two higher than that of a sensor with a signal without modulation.