The magnetic checking of value documents with highly coercive and/or lowly coercive magnetic regions, involves after the magnetization of all magnetic regions in a first direction, a second magnetization is effected, in which only the lowly coercive magnetic material is re-magnetized, but the highly coercive magnetic material remains aligned in the first magnetization direction. Magnetic signals are detected with an inductive magnetic detector, having several measuring tracks transverse to the transport direction of the value document. To evaluate the magnetic signals of the measuring tracks, the strongest two local minima and/or maxima of the respective magnetic signal are ascertained by a measuring track as a function of time. A minima comparison value and/or maxima comparison value of the respective measuring track is determined. The magnetic coding of the security element is checked on the basis of the minima comparison values and/or maxima comparison values of the measuring tracks.

The magnetic checking of value documents with highly coercive and/or lowly coercive magnetic regions, involves after the magnetization of all magnetic regions in a first direction, a second magnetization is effected, in which only the lowly coercive magnetic material is re-magnetized, but the highly coercive magnetic material remains aligned in the first magnetization direction. Magnetic signals are detected with an inductive magnetic detector, having several measuring tracks transverse to the transport direction of the value document. To evaluate the magnetic signals of the measuring tracks, the strongest two local minima and/or maxima of the respective magnetic signal are ascertained by a measuring track as a function of time. A minima comparison value and/or maxima comparison value of the respective measuring track is determined. The magnetic coding of the security element is checked on the basis of the minima comparison values and/or maxima comparison values of the measuring tracks.

A single magnetoresistor TMR magnetic field sensor chip and magnetic currency detector head; the single magnetoresistor TMR magnetic field sensor chip is installed above a magnetic excitation element; the sensing direction of the chip is parallel to the surface of the chip, and the direction of the magnetic excitation field generated at the chip by the magnetic excitation element is perpendicular to the surface of the chip; the chip comprises a substrate, a magnetic biasing structure deposited on the substrate, a magnetoresistive element, and an input/output terminal; the magnetoresistive element consists of MTJs; the sensing directions of the magnetoresistive element and the MTJs are the same as the sensing direction of the chip; and the direction of a bias magnetic field generated on the chip by the magnetic biasing structure is perpendicular to the sensing direction of the chip. The chip features high sensitivity, high signal-to-noise ratio, small size, high temperature stability and high reliability.

A single magnetoresistor TMR magnetic field sensor chip and magnetic currency detector head; the single magnetoresistor TMR magnetic field sensor chip is installed above a magnetic excitation element; the sensing direction of the chip is parallel to the surface of the chip, and the direction of the magnetic excitation field generated at the chip by the magnetic excitation element is perpendicular to the surface of the chip; the chip comprises a substrate, a magnetic biasing structure deposited on the substrate, a magnetoresistive element, and an input/output terminal; the magnetoresistive element consists of MTJs; the sensing directions of the magnetoresistive element and the MTJs are the same as the sensing direction of the chip; and the direction of a bias magnetic field generated on the chip by the magnetic biasing structure is perpendicular to the sensing direction of the chip. The chip features high sensitivity, high signal-to-noise ratio, small size, high temperature stability and high reliability.

A method of determining a currency type and denomination of a bill inserted into a bill acceptor includes receiving the bill inserted into the bill acceptor, the bill acceptor being a single bill acceptor accepting bills of a plurality of currency types, scanning the inserted bill after receiving the inserted bill and determining physical attributes of the inserted bill, and comparing the physical attributes of the inserted bill with attribute characteristics of entries stored in a database. The method also includes determining whether the inserted bill has a matching entry in the database, determining the currency type and denomination of the inserted bill upon determining that the inserted bill has the matching entry in the database, and indicating the determined currency type and denomination and that the inserted bill was successfully accepted in response to determining that the inserted bill has the matching entry in the database.

A method of determining a currency type and denomination of a bill inserted into a bill acceptor includes receiving the bill inserted into the bill acceptor, the bill acceptor being a single bill acceptor accepting bills of a plurality of currency types, scanning the inserted bill after receiving the inserted bill and determining physical attributes of the inserted bill, and comparing the physical attributes of the inserted bill with attribute characteristics of entries stored in a database. The method also includes determining whether the inserted bill has a matching entry in the database, determining the currency type and denomination of the inserted bill upon determining that the inserted bill has the matching entry in the database, and indicating the determined currency type and denomination and that the inserted bill was successfully accepted in response to determining that the inserted bill has the matching entry in the database.

A system and method of using the same, wherein the system comprises: an optical surface having a diffractive image generating structure disposed thereon, the diffractive image generating structure itself comprising a layer of reflective material incorporating a plurality of grooved diffractive elements each having a periodic wave surface profile, the periodic wave surface profiles each having a groove alignment direction; a source of incident electromagnetic radiation arranged to illuminate the diffractive elements at an angle of incidence substantially normal to the plane of the surface of the diffractive elements; means for polarising the radiation from the source, and means for polarising radiation reflected from the diffractive elements; wherein the diffractive elements are configured such that, in use, polarisation conversion of the incident radiation takes place, and wherein the diffractive elements are disposed in a two dimensional array of pixels to represent an image; and further wherein the means for polarising is arranged to pass incident radiation having a polarisation state of approximately 45° azimuth to the groove alignment direction, and is arranged to select a polarisation, using the means for polarising the radiation reflected from the diffractive elements, and to pass radiation of the selected polarisation to a detection point.

A magnetic currency verification head may include a magnetoresistive sensor chip, and a magnetic bias unit disposed on the side of the magnetoresistive sensor chip away from the detection surface of the magnetic currency verification head, and separated from the magnetoresistive sensor chip; the magnetoresistive sensor chip comprises a gradiometric bridge circuit that includes magnetic sensor elements; the sensitive direction of the magnetic sensor elements is parallel to the detection surface of the magnetic currency verification head; and the magnetic bias unit has a recessed magnetic structure configured such that the magnetic field generated by the magnetic bias unit only has a small magnetic field component in the direction parallel to the detection surface, thereby enabling the magnetic sensor elements to operate in their linear range. As a result, the magnetic currency verification head has high sensitivity and signal-to-noise ratio.

A magnetic currency verification head may include a magnetoresistive sensor chip, and a magnetic bias unit disposed on the side of the magnetoresistive sensor chip away from the detection surface of the magnetic currency verification head, and separated from the magnetoresistive sensor chip; the magnetoresistive sensor chip comprises a gradiometric bridge circuit that includes magnetic sensor elements; the sensitive direction of the magnetic sensor elements is parallel to the detection surface of the magnetic currency verification head; and the magnetic bias unit has a recessed magnetic structure configured such that the magnetic field generated by the magnetic bias unit only has a small magnetic field component in the direction parallel to the detection surface, thereby enabling the magnetic sensor elements to operate in their linear range. As a result, the magnetic currency verification head has high sensitivity and signal-to-noise ratio.

Disclosed is a banknote processing method and device. The banknote processing method includes: scanning a substrate through the image acquisition module while acquiring banknote image data through an image acquisition module to obtain substrate image data; acquiring a characteristic value of the substrate image data; calculating a change value of the characteristic value of the substrate image data relative to a reference characteristic value; judging whether the change value is greater than a preset threshold value; and configuring parameters of the image acquisition module if it is judged that the change value is greater than the threshold value.