| 摘要 |
An ophthalmic lens for the correction of presbyopia having a progressive power surface generated by the line of intersection of an ordered sequence of intersecting spheres and cylinder surfaces, the cylinder surfaces being so chosen as to produce a uniform distribution of aberration and optical power for gently curving smooth optical effect. The progressive power surface surrounds at least a major portion of the boundary of a near viewing surface of substantially spherical configuration. The lens has opposite concave and convex surfaces. <IMAGE> |
