Patent · US Expired

Multifocal lens

US4955712A · kind A · utility

73Cited by

3References

8Claims

0Family size

Assignee

Optische Werke G. Rodenstock · DE

Inventors

Rudolf Barth · Hohenkirchen, DE
Gunther Guilino · Munich, DE
Dieter Kalder · Mörfelden, DE

Key dates

Filing date	Jul 18, 1989
Grant date	Sep 11, 1990
Priority date	—
Expiry date	Jul 18, 2009

Classification

Technology area (CPC G)Physics
CPC primaryG02C7/068
WIPO fieldOptics
WIPO sectorInstruments

Abstract

A multifocal lens is described with a main lens designed for distance vision and a segment designed for near vision. The lens in accordance with the present invention is characterized by the fact that one surface of the segment consists of the progression area and the reading portion of a progressive surface. In an advantageous further development the progressive surface whose progression area and reading portion form one surface of the segment is designed in such a way that its surface astigmatism is concentrated essentially in the distance portion.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.