High-resolution imaging through horizontal-path turbulence

We describe a method that we believe will for the first time allow diffraction-limited imaging through ground-level turbulence with large apertures and at large distances (e. g., 1mm resolution at 1km and at a wavelength of 1 mu m). The key lies in collecting image data in the spatial frequency domain via the method of Fourier telescopy and in taking suitable time averages of the Fourier telescopy signal magnitude and phase. The method requires active illumination of the target with laser light, and the time averages required will likely be of many seconds duration, if not minutes. The scheme will thus not be suitable for time-varying scenes.