  The space-variant wavefront reconstruction problem inherently exists in deep
tissue imaging. In this paper,we propose a framework of Shack-Hartmann
wavefront space-variant sensing with extended source illumination. The
space-variant wavefront is modeled as a four-dimensional function where two
dimensionsare in the spatial domain and two in the Fourier domain with priors
that both gently vary. Here, the affinetransformation is used to characterize
the wavefront space-variant function. Correspondingly, the zonaland modal
methods are both escalated to adapt to four-dimensional representation and
reconstruction.Experiments and simulations show double to quadruple
improvements in space-variant wavefront reconstruction accuracy compared to the
conventional space-invariant correlation method.
