EP1872338A1

EP1872338A1 - Device and method for verifying valuable documents

Info

Publication number: EP1872338A1
Application number: EP06724250A
Authority: EP
Inventors: Thomas Giering; Helmut Steidl; Dieter Stein; Klaus Thierauf
Original assignee: Giesecke and Devrient GmbH
Current assignee: Giesecke and Devrient GmbH
Priority date: 2005-04-12
Filing date: 2006-04-11
Publication date: 2008-01-02
Also published as: US20090225303A1; US8212205B2; RU2419157C2; CN101171610A; DE102005016824A1; ZA200708209B; WO2006108616A1; CA2604512A1; RU2007141567A

Abstract

The invention relates to a device and a method for the automatic verification of sheet-type valuable documents. The aim of the invention is to provide a measuring device with a simple construction. To achieve this, the measuring device at least evaluates measured values at e.g. two measuring frequencies and the position of one or more discrete measuring tracks is defined in such a way that at least the presence of two different non-visible spectral characteristics of a predetermined type of authentic valuable documents can be verified.

Description

Device and method for checking value documents

The invention relates to a device and a method for automatic testing of sheet-shaped value documents.

Although not limited thereto, the invention relates in particular to the examination of banknotes, checks or coupons provided with machine-readable security features which can be visually inspected in the invisible spectral range in order, for example, to check the authenticity and / or the nominal value of the value document or to be determined. Such visible in un- ^'spectral range detectable security features can, for example in the ultraviolet or infrared (abbreviated IR) to be emitting or absorbing substances, which are contained in the ink or in the banknote paper. :

Systems for optical testing of such value documents are known, for example, from DE 10007887 A1, DE 19701513 C2, WO 2004/036508, US Pat. No. 5,757,001 or EP 1233261 A1.

Starting from this prior art, it is the object of the present invention to enable effective testing of such documents of value with a simple and inexpensive constructed measuring device.

This object is solved by the independent claims. The dependent claims and the following description illustrate preferred embodiments.

Thus, according to the present invention, a simply constructed measuring device can be obtained by, for example, using the measuring device. At least two measuring frequencies evaluates measured values and the position of one or more discrete measuring tracks is determined such that at least the presence of two different non-visible spectral properties of a given type of genuine value documents can be tested. The measuring device will preferably be designed for measurement in the infrared spectral range and the different non-visible spectral properties will be, for example, different spatial and / or spectral characteristics of the measured values.

When transported in longitudinal transport relative to the measuring device value documents already a single measuring track and transported in transverse transport relative to the measuring device value documents already two measurement tracks may be sufficient to check different non-visible spectral properties and thus to allow safe testing at low cost of the measuring device , The measuring device can not only be firmly integrated in a processing device, but preferably also be a hand-held test device in which the banknotes are conveyed past the measuring elements of the measuring device in the longitudinal or transverse transport automatically or manually.

Further advantages of the present invention will become apparent from the dependent claims and the following description of preferred embodiments with reference to the accompanying figures.

It should be particularly emphasized that the features of the dependent claims and the embodiments mentioned in the following description in Combination or independently and can be used advantageously by the subject of the main claims.

The show

Figure 1 is a schematic cross-sectional view of a measuring device for banknotes according to a first embodiment;

Figure 2 is a schematic view in the visible spectral region on the front of a banknote, which is tested with the measuring device of Figure 1;

Figure 3 is a schematic view in the visible spectral range on the

Rear side of the banknote of Figure 2, which is tested with the measuring device of Figure 1 and

Figure 4 is a schematic view in the infrared spectral range on the

Rear side of the banknote of Figure 2, which is tested with the measuring device of Figure 1.

Although not limited to this, the following section deals in particular with the examination of banknotes in the infrared spectral range. Additionally or alternatively, it is also possible to measure in other non-visible spectral ranges.

FIG. 1 shows, in a merely exemplary manner, a schematic cross-sectional view of a measuring device 1 for banknotes BN according to an embodiment of the invention. Most embodiments. Such measuring devices 1 can be used, for example, in paper making, banknote printing, bank note counting, bank note payment and / or banknote dispensing devices, vending machines or in other banknote processing devices. In addition, the use as a handheld tester is possible.

The measuring device 1 has two preferably identically constructed sensor modules 2 and 3, between which a banknote to be checked BN is transported in the direction T. In this case, the transport is a transverse transport. This means that the banknotes BN are transported in the direction T parallel to the shorter banknote edges.

The sensor modules 2, 3 each have a housing 7, in which a light source 6 for large-area illumination of the banknote BN at least with infrared light and two separate detectors 4a, 5a and 4b, 5b are included, which of different areas of the banknote BN capture outgoing light in reflection. By the bill BN is transported during the measurement in the direction T between the sensor modules 2, 3, the detector units measure 4a, 5a and 4b, 5b in spaced apart measuring tracks Sl and S2 on the front and S3 and S4 on the back of the banknote BN outgoing infrared radiation.

These measuring tracks are illustrated in FIGS. 2 to 4 for the upper sensor module 2 with the dashed outline lines S1 (detector 4a) and S2 (detector 5a). FIG. 3 illustrates the corresponding measuring tracks of the lower sensor module 3 with the dashed outline lines S3 (detector 4b) and S4 (detector 5b). Furthermore, the detectors 4a, 5a and 4b, 5b respectively measure at at least two different infrared frequencies or frequency ranges. As explained below, the determination of the measuring tracks and measuring frequencies is effected as a function of the properties of the documents of value to be tested.

The measured values of the sensor modules 2, 3 are fed via data line to an EDP-supported ejection unit 8. The evaluation unit 6 is either part of the measuring device 1 or a separate component.

The measuring device 1 is designed for automatic testing of one or more predetermined types of banknotes BN. Banknotes of a different currency, but also banknotes BN of different denominations of a common currency can be understood here as different types of banknotes.

In order to explain the system according to the invention, reference will now be made, in a merely exemplary manner, to the examination of the banknote BN of FIGS. 2 to 4 with the aid of the measuring device 1 according to FIG.

The banknote BN is in each case shown together with the associated measuring tracks S1-S4 in a view of the front side (FIG. 2) or the rear side (FIGS. 3, 4). Figures 2 and 3 show the banknote BN as it shows in the visible spectral range and Figure 4 shows how the banknote BN is perceived in the infrared spectral range. The examination of such banknotes BN with the measuring device 1 can now take place as follows:

First, the presence, location and distribution of testable infrared spectral properties is determined experimentally by measuring genuine banknotes BN. Subsequently, the distance of the two detectors 4a, 5a or 4b, 5b per sensor module 2 or 3 is set or predetermined so that at least the presence of two different measured tracks S1, S2 or S3, S4 by evaluating the measured values. different infrared spectral properties of this banknote BN can be checked at least two measuring frequencies. The different infrared spectral properties can e.g. relate to a different spatial and / or spectral course of the measured radiation of the banknote BN.

It should be emphasized that these different spectral characteristics usually differ for different banknote currencies. Accordingly, the definition of the measuring tracks Sl, S2 or S3, S4 and measuring frequencies will of course differ, depending on whether, for example. Euros, Swiss Francs, British Pounds, Swedish Krona, US Dollars or Japanese Yen are tested according to the invention.

For example, it is also possible to check banknotes BN in which an infrared absorber is present only in at least a partial area of the entire banknote surface and the measurement track position is determined in such a way that the presence of the infrared absorber in the particular subarea is checked as a first infrared spectral property. Infrared absorbers are well-known mals in banknote paper or printing ink, which absorb in the infrared spectral range, so that the banknotes remit when measured in this absorbing frequency ranges significantly less infrared radiation than banknotes without infrared absorber. Examples of this are described, for example, in WO 03/038001 A1.

In the merely exemplary example of a banknote according to FIGS. 2 to 4, a first infrared absorber (only) is present in the graphic structures 11, 12 of the front side and a second infrared absorber with a different absorption spectrum (only) in the printing ink of the nominal value imprint 16 of the reverse side of the banknote BN available.

In addition to these regions 11, 12 and 16, respectively, with different infrared spectral properties, the inks of the graphic structure 18 have the back side, the signature 14 and the denomination print 13 on the front side and the print colors of the serial numbers 15, 17 on the front side and the back side, respectively, in the infrared luminescent substances which have a different spectral behavior than the two infrared absorbers.

In addition, the banknote BN has two so-called infrared sections 20, 21 on the rear side. These are the dotted areas reproduced in the infrared view of Figure 4, in which the intensity in the infrared is largely homogeneous. In contrast to this, the surrounding areas usually have no or a significantly more spatially varying distribution of the intensity in the infrared. For example, in the graphic structures 11 and 18, the intensity in the infrared varies much more strongly and similarly as in the visible spectral range. This difference is illustrated by way of example by the measurement curves M3, M4 in FIG. 4, the intensity I being plotted over the location X of the measurement along the tracks S3 and S4. Via the track S3, ie in particular in the region of the infrared section 20, the IR intensity is largely constant, while it is spatially more modulated on the track 4.

Now that the position and properties of the banknotes BN to be tested have been determined, the position and the spacing of the detectors 4a, 5a or 4b, 5b or the associated measuring tracks S1, S2 or S3, S4 are then determined so that at least two of these different IR characteristics can be tested.

For checking the banknote BN transported past in the transverse transport of FIGS. 2 to 4, the two detectors 4a, 5a or 4b, 5b per side already suffice for the IR properties of the regions 11, 14, 15, 16, 18, 20 to consider. Even if no measurement of the IR properties of the regions 12, 13, 17 and 21 is possible in this case, since they lie outside the measuring tracks S1, S2 or S3, S4, the vast majority of counterfeits can already be detected with this sensor.

It should again be emphasized that, depending on the banknote to be checked, measuring in just one track, in particular in the case of a longitudinal transport parallel to the longer banknote edge, may already be sufficient. Another advantage of the measuring device 1 of Figure 1 is that the said IR properties can also be checked independently of the position of the banknote BN, ie not only when the front and back, but also when left and right are reversed. In the illustrated position of the banknote BN, the presence of the IR section 20 can thus be checked, for example, by means of the track S3. If the banknote BN instead is in a position rotated by 180 ° in the plane of the paper, the IR section 20 can be measured by means of the track S4 and, if the front or rear side of the IR section 20 is exchanged, by the tracks S1 or S2. As a result, with this measuring device 1, a position determination can be carried out, since the measurements of the four tracks S1-S4 in real banknotes BN must always be in predetermined relation to each other.

Advantageously, all or part of the measuring tracks will be arranged symmetrically with respect to the banknote BN. Thus, the measuring tracks S1 to S2 or S3 to S4 are arranged so that their distance from the parallel to the transport direction T extending left edge (measuring tracks Sl, S3) and right edge (measuring tracks S2, S4) are equal.

As mentioned, it is necessary that not only the spatial distribution at one frequency, but at least for a part of the properties to be tested, the IR spectrum be measured at at least two spectrally different, preferably at least two spectrally spaced frequencies. The choice of measurement frequencies will in turn depend on the actual material properties of the banknote paper or its ink. In a merely exemplary way, the US 5,757,001, in which, for example, with reference to FIG. 4, it is described in detail that a measurement at two different infrared wavelengths around 870 and 930 nm in certain areas of a banknote BN may be sufficient in order to take account of the different ratios of the measurement intensities to be able to distinguish between these two wavelengths between real and false banknotes.

Thus, e.g. Also, the presence of an infrared absorber in the sub-areas 11 and / or 16 are checked by at least some or all detectors 4a, 5a and 4b, 5b measured values measured at at least two different IR frequencies and in the evaluation unit 8 with an expected spectral course be compared with the at least two different IR frequencies for real value documents, for example for the different infrared absorbers also different from each other.

In addition, a further IR spectral property can be tested in another infrared absorber-free subarea by comparing measured values at at least one frequency with another expected spectral characteristic for real banknotes BN. This can be, for example, the measurement of the IR section 20 at only one IR measurement frequency. The combination of the measurement of IR absorbers and IR sections is an example that a different number of measurement frequencies is necessary to check the presence of the different spectral properties. It should be emphasized that a particularly significant advantage of the present invention results precisely from a combination of several such different evaluations, such as testing not only for IR absorbers, but also eg also on an IR cut. This significantly reduces the probability of a faulty evaluation.

In addition to the examples described, other variants are conceivable.

Thus, it has been described above by way of example that the IR absorber only in the ink of the graphic front side structures 11, 12 and the Rücksei ten-nominal value 16 are included. Of course, this is merely exemplary, and the infrared absorbers or other feature substances to be tested in the infrared can also be present and tested in other sub-areas of the banknote substrate and / or the printed image in the case of genuine banknotes BN. also be produced by means of steel gravure, book printing, indirect high-pressure and / or offset printing and / or may also be part of another graphic structure, such as a serial number 15, 17, a signature 14, a bank seal, an issue date, a watermark or the like.

It should also be noted that the infrared radiation does not necessarily have to be measured in reflection, but in other variants additionally or alternatively also infrared radiation in transmission, i. can be measured through the banknote BN.

Finally, it should be emphasized that further measurements can also be carried out in the same measuring device 1 or a further measuring device in order to check the authenticity and / or the nominal value of the banknote BN. For example, it is also possible to carry out UV measurements in transmission and / or reflection in order, for example, also to detect UV brighteners can. Since these are mostly largely distributed over the entire surface in the banknote paper, an associated UV measuring tracks can be placed anywhere on the banknote surface. In the example described, it can be placed for example between or next to the measuring tracks Sl, S2 or S3, S4. In addition, other than optical measurements, such as conductivity measurements or magnetism measurements to check the banknotes can be performed.

Claims

Patent claims

1. A method for automatic checking of sheet-shaped value documents (BN), comprising the following steps: - determining the position of one or more measuring tracks (S1, S2, S3,

S4) of a measuring device (1) such that at least the presence of two different non-visible spectral properties of a given type of genuine value documents (BN) can be checked, - irradiating the value document (BN) along the measuring tracks (S1, S2,

S3, S4),

Acquisition of measured values (M3, M4) of the irradiated value document (BN) along the measuring tracks (S1, S2, S3, S4), at least in a part of the measuring tracks (S1, S2, S3, S4) being measured at at least two spectrally spaced measuring frequencies becomes,

Determine whether the at least two different spectral properties of the given type of true value documents (BN) were detected.

2. The method according to claim 1, characterized in that the presence of documents of value (BN) is checked, in which an infrared absorber only in at least a partial surface (11, 16) of the entire value document surface is present and the Meßspurlage is set so that the presence of the infrared absorber in the particular area can be checked.

3. The method according to claim 1 or 2, characterized in that the measurement frequencies and / or the Meßspurlage (S2) are determined so that the presence of an infrared absorber in a certain sub-area (11) is checked by measuring a measurement track at least two different Frequencies are compared with an expected spectral characteristic for real value documents (BN)

4. The method according to at least one of the preceding claims, characterized in that a second spectral property in another, infrared absorber-free face (14, 18) is checked by measuring at least one frequency with another expected spectral property for real value documents (BN) be compared.

5. The method according to at least one of the preceding claims, characterized in that a different number of measurement frequencies is necessary to check the presence of different spectral properties and / or at least a portion of the measuring tracks (Sl, S2, S3, S4) symmetrically in relation is arranged on the location of the value document to be checked (BN).

6. The method according to at least one of the preceding claims, characterized in that the infrared absorber in real value documents (BN) only in a partial area (11, 12, 16) of the value document substrate and / or the printed image of the value document (BN) is present and is checked , wherein the partial surface was produced by means of steel gravure printing, letterpress printing, indirect high-pressure and / or offset printing and / or part of a graphic structure, such as a serial number (15, 17), a currency indication (13, 16), a signature (14), a portrait image (11), a bank seal, an issue date, a watermark, or the like.

7. The method according to at least one of the preceding claims, characterized in that a first of the spectral properties to be tested, a check for the presence of an infrared absorber and a second spectral property to be tested is a check for the presence of an infrared cut in the value document surface.

8. Measuring device (1) designed for carrying out the method according to at least one of claims 1 to 7.