SPECTACLE LENSES INCORPORATING ATORIC SURFACES

摘要

An atoric surface is formed such that the surface coordinate lines are parallels with the shape of off-set curves of the trajectory curve of a swept surface, and meridians with the shape of the section curve of such swept surface. The lines of curvature of the surface coincide with the coordinate lines, so that the surface cylinder axis at any point P of the atoric surface is tangent to one of the two coordinate lines that passes through P. Atoric surfaces with lines of curvature in the form of meridian and parallel curves are highly suitable for astigmatic surfaces in spectacle lens design. The atoric surface design methodology provided herein is used to generate a broad range of surfaces from this class, thereby providing substantial flexibility over prior methods.