Sensor for sensing fingerpaints and method for producing the sensor

US5373181A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Thomas Scheiter · Munich, DE
• Markus Biebl · Augsburg, DE
• Helmut Klose · Munich, DE

Key dates

• Filing date: Oct 25, 1993
• Grant date: Dec 13, 1994
• Expiry date: Oct 25, 2013

Classification

• Technology area (CPC G): Physics
• CPC primary: G06V40/1306
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A grid-like arrangement of membranes of doped polysilicon are mounted on a substrate but are electrically insulated therefrom each membrane extends over a cavity and is joined to the substrate at at least two supporting locations so that they cavity lies between the membrane and the substrate. Changes in an electrical quantity existing between the membranes and the substrate are measured as forces exerted on the grid-like arrangement of sensor elements so that the ridges in the skin on a finger tip may be sensed for detecting a fingerprint.