Optical patches are assigned to prescriptions so as to reduce the total number of patch surfaces which are involved. The prescriptions are produced by varying at least one of a front patch surface (S1) and rear patch surface (S2) which are combined to form an optical patch, in accordance with prescription segments. The front patch surfaces (S1) are pseudo-spherical and the rear patch surfaces (S2) are comprised of a Fresnel structure superimposed on a pseudo-spherical base shape.