Fig. 3
Experimental 300 × 128 pixel (column, row) CDFT interferogram of spectrally modulated Xe lamp. The Fourier transform recovered channel spectra magnitudes (a) show wrapping of the linear dispersion about the Nyquist zone for short wavelengths, indicative of undersampling and aliasing in these channels. When simply added, irreversible aliasing is observed in the magnitude (b) as shorter wavelengths are reflected across the critical sampling frequency to overlap with longer wavelengths; this is equivalent to the spectrum recovered from the 1D interferogram of a stationary Fourier transform spectrometer. CDFT spectrometers allow the separation of the aliased components from overlapping channel spectra. Linear dispersion of the spectral channels is restored by unwrapping the aliased channels into an empty half space (c) and recovery by summation recovery (d)
