Sensor element, test device, and method for testing a data carrier having a spin resonance feature

The sensor element according to claim 21, wherein the stripline resonators of the resonator device are arranged in the shape of a one-dimensional array, in that the one-dimensional array is arranged in parallel with a gradient of the magnetic flux in the air gap.

The sensor element according to claim 21, wherein the stripline resonators of the resonator device form a multitrack arrangement having a plurality of parallel tracks, in which each track is formed by a one-dimensional array of stripline resonators,

• wherein the one-dimensional array of each track is arranged in parallel with a gradient of the magnetic flux in the air gap.

The sensor element according to claim 21, wherein the stripline resonators arranged at different positions in the air gap are each fed by a different signal source.

The sensor element according to claim 21 wherein the air gap is bounded by two pole faces of the magnetic core,

• wherein one or both pole faces have a beveled and/or stepped embodiment.

The sensor element according to claim 21, wherein the stripline resonators of the resonator device have the same resonant frequency, in that the stripline resonators moreover are designed and configured to test the spin resonance feature in the same spatial mode of the excitation field, in that the stripline resonators have an identical geometric shape.

The sensor element according to claim 21, wherein the aforementioned first field strength differs by at least 2% from the aforementioned second field strength.

The sensor element according to claim 21, wherein the sensor element comprises a modulation device for creating a time-varying magnetic modulation field in the air gap,

• wherein the modulation frequency is equally high at the location of each of the stripline resonators of the resonator device.

The sensor element according to claim 21, wherein the stripline resonators have a planar embodiment with a principal plane of extent which is perpendicular to the direction of static magnetic flux created by the polarization device.

The sensor element according to claim 21, wherein the air gap has a height of less than 10 mm.

The sensor element according to claim 21, wherein the sensor element comprises a ramp coil for creating a ramp function of the static magnetic flux.

A test apparatus for testing a planar data carrier having a spin resonance feature, comprising:

• a sensor element according to claim 21 and
• one or more signal source(s) by which the stripline resonators of the resonator device which are arranged at different positions in the air gap are fed.