The invention relates to so-called progressive medical eyeglass lenses. A progressive lens is a type of lens for making eyeglasses for correcting human vision defects, being adapted simultaneously to far vision and to near vision. The present invention makes it possible to reconcile a design that is finely optimized over a wide range of variables; it enables the looked-for optical powers to be made for any progressive lens prescription while controlling and obtaining a distribution of virtually identical optical values on the entire surface of the lens, and doing so for a wide range of materials (i.e. of refractive indices) e.g. lying in the range 1.498 to 1.74 (values mentioned here in non-exhaustive manner), and for any combination of refractive index, of basecurves lying in the range 0.5 diopters to 10.5 diopters, and for any addition values, over an addition range of 0.5 diopters to more than 3.5 diopters. This design presents exceptional “robustness”, thereby eliminating the major obstacle of conventional progressive lenses that present characteristics that vary strongly and that depend strongly on the selected materials, basecurves, and additions.