Identification card with a visible authenticity feature

US4894110A · kind A · utility

Assignee

• GAO Gesellschaft für Automation und organisation mbH · DE

Inventors

• Joseph Lass · Munich, DE
• Hansjurgen Merkle · Munich, DE
• Wolfgang Becker · Eppstein, DE
• Werner Herget · Munich, DE
• Erwin Lob · Munich, DE

Key dates

• Filing date: Jun 29, 1988
• Grant date: Jan 16, 1990
• Expiry date: Jun 29, 2008

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/24942
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

Information is provided in a multilayer identification card by means of a laser beam. This information is recorded by irreversibly changing (blackening) transparent synthetic material. Synthetic materials which blacked at different intensity values are used for the individual card layers. By controlling the laser beam intensity, information can thus be recorded only in one layer or else simultaneously in several layers. If the layer arrangement, layer materials and recording parameters (intensity, writing width, etc.) are selected appropriately, images can be produced which change their appearance when the viewing angle is changed. The various visual effects which can thereby be obtained serve to distinguish the authenticity of the identification card.