This work centers on an optimization of the current integration method for determining the field radiated by a centered parabolic reflector fed at its focus. A nonredundant sampling representation of the physical optics (PO) current, induced on the main reflector by the electromagnetic field radiated from the primary field source, and an optimal sampling interpolation algorithm are developed to this end. Such an approach allows one to reduce the number of points where the knowledge of the current is required, so that the computation time decreases remarkably when the evaluation of the field radiated from the feed is burdensome.