A system including a data requester and a storage system. The Faraday cup, the current branch circuit and the operation amplifier are formed as a portion of an ion implanter. The method also includes determining a characteristic of individual regions on the specimen using the properties of the individual pixels in the individual regions. A first switch generates a first sensor signal dependent on the current flowing through the first switch, andor a second sensor unit, which detects whether demagnetization of the coil unit has occurred and generates a sensor signal.