Method of removing excess lens forming material from a molded ophthalmic lens such as a contact lens

US8721934B2 · kind B2 · utility

Assignee

• Novartis AG · CH

Inventors

• Axel Heinrich · Aschaffenburg, DE
• Roger Biel · Aschaffenburg, DE
• Günter Lässig · Obernburg, DE
• Jan Bernard · Niedernberg, DE
• Stephan Pirl · Obernburg, DE

Key dates

• Filing date: Dec 16, 2010
• Grant date: May 13, 2014
• Expiry date: Apr 23, 2031

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B29L2011/0041
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

There is described a method of removing excess lens forming material from a molded ophthalmic lens (1), such as the peripheral region of a contact lens. In order to form a lens (1) a lens forming material is polymerized and/or cross-linked within a mold cavity of a mold comprising female and male mold halves. The mold is opened by moving the female and male mold halves apart from each other. The formed lens (1) is supported on a carrier (3) such, that a front surface (2) of the lens (1) is exposed. Residues of non-polymerized and/or non-cross-linked lens forming material are removed mechanically by contacting the exposed surface (2) of the formed lens (1) for a period of time of about 0.5 seconds to about 4 seconds, preferably about 0.8 seconds to about 2 seconds, with a cleaner (7) having a hardness which is smaller than that of the polymerized and/or cross-linked lens forming material. There is also described a device (5) for carrying out the method.