SENSOR ELEMENT AND DEVICE FOR AUTHENTICITY VERIFICATION OF A DATA CARRIER WITH A SPIN RESONANCE FEDERATION

Abstract

The invention relates to a sensor element (26) for checking the authenticity of a planar data carrier (10), in particular a banknote, having a spin resonance feature (12). The sensor element contains a magnetic core (22) having an air gap (24), into which the flat data carrier (10) can be inserted for authentication and which defines an axial direction extending between the adjoining surfaces of the magnetic core (22), a polarization device for generating a static magnetic flux in the air gap (24), a modulation device (30) for generating a time-varying magnetic modulation field in the air gap (24), and a resonator for exciting the spin resonance feature (12) of the data carrier (10) to be checked. According to the invention, it is provided that the modulation device is formed by at least one planar coil (30) arranged in the air gap, which planar coil has in one plane one or a plurality of windings about the axial direction of the air gap. The invention also relates to a test device having such a sensor element.