Spectacle lens

US5444503A · kind A · utility

Assignee

• Carl Zeiss Stiftung · DE

Inventors

• Gerhard Kelch · Aalen, DE
• Hans Lahres · Aalen, DE
• Helmut Wietschorke · Laberweinting, DE

Key dates

• Filing date: Mar 25, 1993
• Grant date: Aug 22, 1995
• Expiry date: Mar 25, 2013

Classification

• Technology area (CPC G): Physics
• CPC primary: G02C7/061
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

The invention is directed to a spectacle lens having a multifocal surface and a prescription surface. The prescription surface is a general aspheric surface without point and axis symmetry. Of the individual use conditions, at least the dioptric power is considered within an area when determining the geometry of the prescription surface. The prescription surface is provided exclusively for generating the dioptric power in the reference points and additionally for eliminating the increase of imaging errors.