Polymer morphologies can be analyzed by various experimental projection methods. Since most structures live in three dimensions the problem is to extrapolate the underlying 3D morphology from the projection. We propose an approach in which the free energy functional of a 3D sample is minimized to fit experimental 2D information, serving as an additional constraint. The method is very general and can be applied to any physical system described in terms of a density functional theory. (C) 2003 American Institute of Physics.