Metallic profile and coin imaging using an inductive proximity sensor microsystem

Abstract We have realized metallic profile and coin imaging using a miniaturized inductive proximity sensor. The sensor is a microsystem composed of a 1 mm diameter coil and a new ASIC interface based on the principle of a differential relaxation oscillator. We successfully acquired wellrecognizable images of various coins with different geometrical, electrical and magnetic properties. The integration of such sensor microsystems on a line will open the way to fast and safe coin pattern recognition.

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