A security document includes a non-homogeneous region formed e.g. by a structure of bars that vary the document's thickness dielectric permittivity or electrical conductance. The structure is verified by placing the document on the capacitive touchscreen of a verification device. Then, the user moves a finger or pen along the structure, which gives rise to a varying capacitive signal in the verification device. The signal can then be analyzed for deriving information about the document.

A security document includes a non-homogeneous region formed e.g. by a structure of bars that vary the document's thickness dielectric permittivity or electrical conductance. The structure is verified by placing the document on the capacitive touchscreen of a verification device. Then, the user moves a finger or pen along the structure, which gives rise to a varying capacitive signal in the verification device. The signal can then be analyzed for deriving information about the document.

An apparatus and method for classifying value documents includes least two sensor devices arranged to capture waves reflected on a front side and on a back side of a value document and to generate corresponding sensor data or to capture properties of the value document in at least two different regions of the value document by means of different measuring principles and to generate corresponding sensor data. At least one evaluation device is arranged to classify the value document with the aid of the sensor data generated by the at least two sensor devices, which sensor data relate to the waves reflected on the front side and back side of the value document or to the properties of the value document captured in the at least two different regions of the value document by means of different measuring principles.

An apparatus and method for classifying value documents includes least two sensor devices arranged to capture waves reflected on a front side and on a back side of a value document and to generate corresponding sensor data or to capture properties of the value document in at least two different regions of the value document by means of different measuring principles and to generate corresponding sensor data. At least one evaluation device is arranged to classify the value document with the aid of the sensor data generated by the at least two sensor devices, which sensor data relate to the waves reflected on the front side and back side of the value document or to the properties of the value document captured in the at least two different regions of the value document by means of different measuring principles.

A capacitance detection device includes a first electrode and a second electrode that at least partially face each other on opposite sides of a transfer path. An oscillator circuit forms an electric field between the first electrode and the second electrode. A detection circuit detects a change in capacitance between the first electrode and the second electrode. At least one of the oscillator circuit and the detection circuit is included in each of a first board and a second board. The first board is disposed such that a side surface of the first board faces the first electrode in an electric field direction, and the second board is disposed such that a side surface of the second board faces the second electrode in the electric field direction.

A capacitance detection device includes a first electrode and a second electrode that at least partially face each other on opposite sides of a transfer path. An oscillator circuit forms an electric field between the first electrode and the second electrode. A detection circuit detects a change in capacitance between the first electrode and the second electrode. At least one of the oscillator circuit and the detection circuit is included in each of a first board and a second board. The first board is disposed such that a side surface of the first board faces the first electrode in an electric field direction, and the second board is disposed such that a side surface of the second board faces the second electrode in the electric field direction.

A sensor device includes a detection electrode opposing an external electrode, and generating a voltage corresponding to a change in capacitance; a capacitive amplifier circuit having a first capacitor and a second capacitor, and configured to detect the voltage generated in the detection electrode, and output a detection signal obtained by amplifying the voltage generated in the detection electrode based on a capacitance ratio between the first capacitor and the second capacitor; a reset switch configured to reset the voltage of the detection electrode to a reference potential; a changeover switch configured to switch the capacitive amplifier circuit between a capacitive amplifier and a voltage follower; a second changeover switch configured to disconnect the first capacitor from the capacitive amplifier circuit; and a second reset switch configured to reset a voltage of the first capacitor to the reference potential.

A capacitance detection device includes a first electrode and a second electrode that at least partially face each other on opposite sides of a transfer path. An oscillator circuit forms an electric field between the first electrode and the second electrode. A detection circuit detects a change in capacitance between the first electrode and the second electrode. At least one of the oscillator circuit and the detection circuit is included in each of a first board and a second board. The first board is disposed such that a side surface of the first board faces the first electrode in an electric field direction, and the second board is disposed such that a side surface of the second board faces the second electrode in the electric field direction.

A capacitance detection device includes a first electrode and a second electrode that at least partially face each other on opposite sides of a transfer path. An oscillator circuit forms an electric field between the first electrode and the second electrode. A detection circuit detects a change in capacitance between the first electrode and the second electrode. At least one of the oscillator circuit and the detection circuit is included in each of a first board and a second board. The first board is disposed such that a side surface of the first board faces the first electrode in an electric field direction, and the second board is disposed such that a side surface of the second board faces the second electrode in the electric field direction.

A capacitance detection device includes a first electrode and a second electrode that at least partially face each other on opposite sides of a transfer path. An oscillator circuit forms an electric field between the first electrode and the second electrode. A detection circuit detects a change in capacitance between the first electrode and the second electrode. At least one of the oscillator circuit and the detection circuit is included in each of a first board and a second board. The first board is disposed such that a side surface of the first board faces the first electrode in an electric field direction, and the second board is disposed such that a side surface of the second board faces the second electrode in the electric field direction.