System for optically examining plastic card surfaces

US6243162A · kind A · utility

Assignee

• MELZER MASCHINENBAU GMBH · DE

Inventors

• Bernhard Baist · Wuppertal, DE
• Alexander Melzer · Neutillmitsch, AT

Key dates

• Filing date: Jul 16, 1999
• Grant date: Jun 5, 2001
• Expiry date: Jul 16, 2019

Classification

• Technology area (CPC G): Physics
• CPC primary: G07D7/12
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

In the optical examination of plastic cards, the latter are illuminated with focused light, which is mixed with a diffuse component, in order reliably to discriminate even relatively slight differences in the reflectivity of the surface sections.