Patent · US Expired

Lens inspection

US6765661B2 · kind B2 · utility

27Cited by

58References

25Claims

0Family size

Assignee

Novartis AG · CH

Inventors

Roger Biel · Aschaffenburg, DE
Joachim Linkemann · Ahrensburg, DE
Livio Fornasiero · Bliestorf, DE
Ingolf Braune · Waldkirch, DE

Key dates

Filing date	Mar 6, 2002
Grant date	Jul 20, 2004
Priority date	—
Expiry date	Aug 14, 2022

Classification

Technology area (CPC G)Physics
CPC primaryG01N21/958
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

The invention enables more objective defect evaluation of ophthalmic lenses, especially contact lenses, to take place through the combination of the schlieren method with the transmitted light method, with the result that the advantages of these two different systems are combined. The schlieren method is in a position to illustrate the edge of a contact lens and its ruptures, in high contrast, for the CCD camera. Likewise, tears and surface defects can be made visible. Using the transmitted light method, the bubbles may be suitably prepared for the camera.

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