title: Third-order theory and aspheric spectacle lens design.
abstract: Third-order equations are developed giving sagittal and tangential power errors corresponding to the eye rotating to look through the periphery of a spectacle lens. The equations are applicable for conicoid aspherical surfaces. From these, other equations are derived for elimination of oblique astigmatism and mean oblique error. Graphical examples show how aspherizing either lens surface affects the lens bendings required to eliminate oblique astigmatism.
mesh_terms: D001251:Astigmatism / Q000534:rehabilitation; D005139:Eyeglasses; D006801:Humans; D008433:Mathematics; D008954:Models, Biological; D011474:Prosthesis Design