Progressive power ophthalmic lens

US4315673A · kind A · utility

Assignee

• Optische Werke G. Rodenstock · DE

Inventors

• Gunther Guilino · Munich, DE
• Rudolf Barth · Hohenkirchen, DE

Key dates

• Filing date: May 5, 1980
• Grant date: Feb 16, 1982
• Expiry date: May 5, 2000

Classification

• Technology area (CPC G): Physics
• CPC primary: G02C2202/08
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

In the disclosed lens, one lens surface is divided into an upper distance-vision portion FT, a lower near-vision portion NT, and a varying or transitional region PB between the two other portions. In the upper distance-vision portion, the surface contains a far reference point B.sub.F and exhibits predetermined average distance-vision surface refractive powers D.sub.F. The lower near-vision portion contains a near-vision reference point B.sub.N and has predetermined average near-vision surface refractive powers D.sub.N. The transitional region exhibits average surface refractive powers D.sub.P which effect a smooth transition from the distance-vision portion to the near-vision portion. The surface is divided into a temporal portion and a nasal portion by a principal meridian M which forms an umbilical line.