Inspection of ophthalmic lenses using absorption

US6577387B2 · kind B2 · utility

Assignee

• Johnson & Johnson Vision Care, Inc. · US

Inventors

• Denwood F. Ross, III · Green Cove Springs, US
• Mary L. Dolan · Jacksonville, US
• Ranganath Raja · Jacksonville, US
• Brian Rice · Jacksonville, US
• Craig William Walker · Jacksonville, US
• David Kappel · Künzelsau, DE
• Robert E. Fischer · Westlake Village, US
• Ture Kindt-Larsen · Vejle, DK

Key dates

• Filing date: Dec 29, 2000
• Grant date: Jun 10, 2003
• Expiry date: May 30, 2021

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N21/59
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method and system for inspecting ophthalmic lenses using absorption where an ophthalmic lens is illuminated with light comprising wavelengths that are substantially absorptive to said lens, the image subsequently detected being created using only light at said absorptive wavelengths. Variations in transmitted light intensity translate into thickness changes in the lens caused by cosmetic flaws. The invention is also directed to imaging lens assemblies employing highly positive-powered field flattening lens elements to image a curved object, such as an ophthalmic lens, onto a flat image plane.